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Characterization of berkelium(III) dipicolinate and borate compounds in solution and the solid state.
Silver, Mark A; Cary, Samantha K; Johnson, Jason A; Baumbach, Ryan E; Arico, Alexandra A; Luckey, Morgan; Urban, Matthew; Wang, Jamie C; Polinski, Matthew J; Chemey, Alexander; Liu, Guokui; Chen, Kuan-Wen; Van Cleve, Shelley M; Marsh, Matthew L; Eaton, Teresa M; van de Burgt, Lambertus J; Gray, Ashley L; Hobart, David E; Hanson, Kenneth; Maron, Laurent; Gendron, Frédéric; Autschbach, Jochen; Speldrich, Manfred; Kögerler, Paul; Yang, Ping; Braley, Jenifer; Albrecht-Schmitt, Thomas E
Berkelium is positioned at a crucial location in the actinide series between the inherently stable half-filled 5f(7) configuration of curium and the abrupt transition in chemical behavior created by the onset of a metastable divalent state that starts at californium. However, the mere 320-day half-life of berkelium's only available isotope, (249)Bk, has hindered in-depth studies of the element's coordination chemistry. Herein, we report the synthesis and detailed solid-state and solution-phase characterization of a berkelium coordination complex, Bk(III)tris(dipicolinate), as well as a chemically distinct Bk(III) borate material for comparison. We demonstrate that berkelium's complexation is analogous to that of californium. However, from a range of spectroscopic techniques and quantum mechanical calculations, it is clear that spin-orbit coupling contributes significantly to berkelium's multiconfigurational ground state. PMID:27563098
International Nuclear Information System (INIS)
A new isotope of berkelium, 242Bk, was produced with a cross section of approx. 10 μb in reactions of boron on uranium and nitrogen on thorium. It decays by electron capture with a half-life of 7 +- 1.3 minutes. The branching ratio for this isotope for alpha decay is less than 1% and that for spontaneous fission is less than 0.03%. 2 figures, 2 tables
Extraction of tetravalent berkelium and cerium by aliquate-336-S-NO3 quaternary ammonium salt
International Nuclear Information System (INIS)
Extraction of tetravalent berkelium and cerium by aliquate-336-S-NO3 quaternary ammonium salt from nitric acid solutions is investigated. The effect of concentrations of nitric acid and extracting agent, nature of an oxidant (potassium bromate, potassium bichromate, mixture of AgNO3 and (NH4)2S2O8) and solvent on the distribution coefficient of berkelium(4) and cerium(4) is studied. It is established that solutions of aliquate-336-S-NO3 in carbon tetrachloride and dichloroethane extract quantitatively tetravalent berkelium from 10-12 M nitric acid solutions and cerium - from 1-10 M nitric acid solutions containing potassium bichromate as an oxidant. It is shown that the value of distribution coefficient for berkelium and cerium depends on the nature of an oxidant and extracting agent concentration. It is established that in the case of extraction by quaternary ammonium salt with one berkelium(4) mole four aliquate-336-SNO3 moles are associated and 1.5-1.6 mole of extracting agent are associated with one cerium(4) mole. It permits to make a conclusion that stoichiometry of extraction reactions by quaternary ammonium salt is not the same for tetravalent berkelium and cerium. It is shown that trivalent transplutonium and rare earth elements are not practically extracted by aliquate-336-S-NO3 from nitric acid solutions
Specially formulated derivatives of an unusual basic compound known as Alcide may be the answer to effective treatment and prevention of the disease bovine mastitis, a bacterial inflammation of a cow's mammary gland that results in loss of milk production and in extreme cases, death. Manufactured by Alcide Corporation the Alcide compound has killed all tested bacteria, virus and fungi, shortly after contact, with minimal toxic effects on humans or animals. Alcide Corporation credits the existence of the mastitis treatment/prevention products to assistance provided the company by NERAC, Inc.
Directory of Open Access Journals (Sweden)
Monica Yadav
Full Text Available Odontomas have been extensively reported in the dental literature, and the term refers to tumors of odontogenic origin. Though the exact etiology is still unknown, the postulated causes include: local trauma, infection, inheritance and genetic mutation. The majority of the lesions are asymptomatic; however, may be accompanied with pain and swelling as secondary complaints in some cases. Here, we report a case of a compound odontome in a 14 year old patient.
Kramer, D.A.
In 2005, seawater and natural brines accounted for 51% of US magnesium compounds production. World magnesia production was estimated to be 14.5 Mt. Most of the production came from China, North Korea, Russia and Turkey. Although no specific production figures are available, Japan and the United States are estimated to account for almost one-half of the world's capacity from seawater and brines.
Takagiwa, Y.; Matsuura, Y.; Kimura, K.
We have focused on the binary narrow-bandgap intermetallic compounds FeGa3 and RuGa3 as thermoelectric materials. Their crystal structure is FeGa3-type (tetragonal, P42/ mnm) with 16 atoms per unit cell. Despite their simple crystal structure, their room temperature thermal conductivity is in the range 4-5-W-m-1-K-1. Both compounds have narrow-bandgaps of approximately 0.3-eV near the Fermi level. Because their Seebeck coefficients are quite large negative values in the range 350-thermoelectric materials both by adjusting the carrier concentration and by reducing the thermal conductivity. Here, we report the effects of doping on the thermoelectric properties of FeGa3 and RuGa3 as n and p-type materials. The dimensionless figure of merit, ZT, was significantly improved by substitution of Sn for Ga in FeGa3 (electron-doping) and by substitution of Zn for Ga in RuGa3 (hole-doping), mainly as a result of optimization of the electronic part, S 2 σ.
Directory of Open Access Journals (Sweden)
José Marcelo Vargas Pinto
Full Text Available Odontomas are the most common types of odontogenic tumors, as they are considered more as a developmental anomaly (hamartoma than as a true neoplasia. The aim of the present study is to describe a clinical case of compound odontoma, analyzing its most commonsigns, its region of location, the decade of life and patient's gender, disorders that may occur as well as the treatment proposed. In order to attain this objective, the method was description of the present clinical case and bibliographic revision, arriving at the result that the treatment for this type of lesion invariably is surgical removal (enucleation and curettage and the prognosis is excellent. The surgical result was followed up in the post-operative period by radiographic exam, and it was possible to conclude that there was complete cicatrization and tissue repair.
Volatile Organic Compounds (VOCs)
... Organic Compounds' Impact on Indoor Air Quality Volatile Organic Compounds' Impact on Indoor Air Quality On this page: ... Exposure Standards or Guidelines Additional Resources Introduction Volatile organic compounds (VOCs) are emitted as gases from certain solids ...
Rasyid, Herlina; Firdaus; Hariani, Nunuk
Abstract. Synthesis of metil ??-(p-hidroksifenil)akrilic from ??-(p-hidroksifenil)akrilat acid and methanol using Dean Stark Trap method had been done. Synthesis of ths compound intended to form the starting material in the subsequent synthesis of amide???s compound through the formation of ester compound. This synthesis using H2SO4 catalyst and Dean Stark Trap method, some of benzena which is added to remove the water that resulting from the reaction. Synthesis of this compound be held at re...
On labelled compounds nomenclature
International Nuclear Information System (INIS)
Different approaches of major labelled compounds producers to their nomenclature in technical and commercial documentation are discussed. Some draft options of a standard technical guide document for labelled compounds nomenclature rules are suggested. Such a document after due discussion by the experts will serve to unification of the labelled compounds nomenclature within the frame of the CMEA member-countries co-operation in this field. The suggested options are based on the general recommendations by the International Union of Pure and Applied Chemistry and incorporate some more accurate definitions originating from the labelled compounds production and application experience
Directory of Open Access Journals (Sweden)
D. A. Konovalov
Full Text Available Polyacetylenes (polyynes are compounds which contain two or more triple bonds in its structure. About 2 000 different polyacetylenes and biogenetically related substances were identified in 24 families of higher plants. However, most of these compounds were found in seven families of flowering plants: Apiaceae (Umbelliferae, Araliaceae, Asteraceae (Compositae, Campanulaceae, Olacaceae, Pittosporaceae and Santalaceae. Polyacetylenes are relatively unstable, chemically and biologically active compounds, and present in fungi, microorganisms, marine invertebrates and other organisms except for plants. Acetylenes form distinct specialized group of chemically active natural compounds, which are biosynthesized in plants of unsaturated fatty acids. In addition to widespread aliphatic polyacetylenes thiophenes dithiacyclohexadienes (thiarubrines, thioethers, sulphoxides, sulphones, alkamides, chlorohydrins, lactones, spiroacetal enol ethers, furans, pyrans, tetrahydropyrans, isocoumarins, aromatic acetylenes were also found in plant species. Polyacetylenes are localized in different plant organs, and can be found both individually and as a compound with carbohydrates, terpene, phenolic and other compounds. Many polyacetylenes are found in the composition of the essential oils of plants and it confirms their strongly marked ecological functions. From biological point of view these compounds are often synthesized by plants as toxic or bitter antifeedants, allelopathic compounds, phytoalexins or broadly antibiotic components. Polyynes are strong photosensitizers. They exhibit anti-inflammatory, anti-coagulant, anti-bacterial, antituberculosis, anti-fungal, anti-viral, neuroprotective and neurotoxic activity. Immunostimulatory influence associated with certain allergenicity of some of these substances was established. Therefore, without a doubt polyacetylenes are of interest for the modern pharmacy and medicine.
Stable isotopes labelled compounds
International Nuclear Information System (INIS)
The catalogue on stable isotopes labelled compounds offers deuterium, nitrogen-15, and multiply labelled compounds. It includes: (1) conditions of sale and delivery, (2) the application of stable isotopes, (3) technical information, (4) product specifications, and (5) the complete delivery programme
D. A. Konovalov
Polyacetylenes (polyynes) are compounds which contain two or more triple bonds in its structure. About 2 000 different polyacetylenes and biogenetically related substances were identified in 24 families of higher plants. However, most of these compounds were found in seven families of flowering plants: Apiaceae (Umbelliferae), Araliaceae, Asteraceae (Compositae), Campanulaceae, Olacaceae, Pittosporaceae and Santalaceae. Polyacetylenes are relatively unstable, chemically and biologically activ...
Nomenclature for labelled compounds
International Nuclear Information System (INIS)
This paper report on isotopically labelled compounds. The first indexing system for isotopically labelled organic compounds is generally credited to Boughton and named after him. An extension of his principles for designating compounds containing hydrogen isotopes has been part of the Chemical Abstracts Service index nomenclature system for many years. After close on five years labor the IUPAC sponsored Commission on Nomenclature of Organic Chemistry presented in 1979 their findings on Isotopically Modified Compounds. The system codified in their rules provides for recognition of various types of isotopic modification and is therefore of more general applicability. Concurrently the rules for the nomenclature of isotopically modified inorganic compounds are developed. These are to be seen as supplementing and extending the guidelines laid down in the IUPAC Inorganic Nomenclature Rules already published
Biokinetics of radioactive compounds
International Nuclear Information System (INIS)
Biokinetics of radioactive compounds in the human organism represent the central notion in this work, consisting of a theoretical and an experimental part. The first chapter contains definitions and explanations on the importance of the biokinetics of radioactive compounds in clinical therapy and pharmaceuticals research as well as for assessing radiation exposure and radiation hazards. Chapter 2 describes the bases of the biokinetics of radioactive compounds in the medical and non-medical sector, and biokinetics. Chapter 3 deals with obtaining biokinetics data for radioactive compounds from investigations in animals and man, evaluation of measurements, transferring data obtained by animal experiments to man, and with the variability of biokinetics data. In Chapter 4 the results of comprehensive studies in literature on the biokinetics of radioactive compounds are summarized. They relate to three areas: professional and environmental incorporation of radioactive compounds, use of radioactive pharmaceuticals in therapy and research, and incorporation of radioactive compounds by embryo and fetus in consequence of the uptake of radioactive compounds by the mother. Chapter 5 gives an assessment of radiation hazards from radioactive compounds in connection with occupational radiation exposure and nuclear diagnostics in vivo, and a comparison with other risks. For that purpose the concept of effective dose equivalent is applied in connection with suitable risk coefficients to professional and nuclear-medical radiation exposure. Chapter 6 is dedicated to measurement of the biokinetics of radioactive compounds in man using conventional devices. The object of Chapter 7 is measurement of the biokinetics of radioactive pharmaceuticals in man by means of single photon emission computed tomography. (orig./MG)
Directory of Open Access Journals (Sweden)
G Girish
Full Text Available The term odontoma has been used as a descriptor for any tumor of odontogenic origin. It is a growth in which both epithelial and mesenchymal cells exhibits complete differentiation. Odontomas are considered as hamartomas rather than true neoplasm. They are usually discovered on routine radiographic examination. Odontomas, according to the World Health Organization, are classified into complex odontoma and compound odontomas. The present paper reports a case of compound composite odontomas.
Girish, G; Bavle, Radhika M; Singh, Manish Kumar; Prasad, Sahana N
The term odontoma has been used as a descriptor for any tumor of odontogenic origin. It is a growth in which both epithelial and mesenchymal cells exhibits complete differentiation. Odontomas are considered as hamartomas rather than true neoplasm. They are usually discovered on routine radiographic examination. Odontomas, according to the World Health Organization, are classified into complex odontoma and compound odontomas. The present paper reports a case of compound composite odontomas. PMID:27194882
Berlin, Joey
Allergist-immunologists say a U.S. Pharmacopeia proposal will mess with an allergy treatment system that's worked for more than a century. The revised standards, if adopted, would remove a key exemption separating allergen extract preparations from the stricter requirements of other compounds. Immunologists say the exemption has allowed them to compound allergen extracts in their own offices, and they've done so safely and effectively millions of times a year. PMID:27175928
Phenolic compounds in flaxseed
Johnsson, Pernilla
The dietary lignan secoisolariciresinol diglucoside (SDG), present in high concentrations in flaxseed, and its metabolites enterolactone and enterodiol are thought to decrease the risk of hormone dependent cancers, cardiovascular disease and other "welfare" diseases. Flaxseed also contains other biologically active phenolic compounds, such as phenolic acids. The understanding of the nature of these compounds is crucial for their possible exploitation in drugs and functional foods. Until the m...
Koizumi, Koji; Charles, Ted; de Keyser, Hendrik
Phenolic Molding Compounds continue to exhibit well balanced properties such as heat resistance, chemical resistance, dimensional stability, and creep resistance. They are widely applied in electrical, appliance, small engine, commutator, and automotive applications. As the focus of the automotive industry is weight reduction for greater fuel efficiency, phenolic molding compounds become appealing alternatives to metals. Current market volumes and trends, formulation components and its impact on properties, and a review of common manufacturing methods are presented. Molding processes as well as unique advanced techniques such as high temperature molding, live sprue, and injection/compression technique provide additional benefits in improving the performance characterisitics of phenolic molding compounds. Of special interest are descriptions of some of the latest innovations in automotive components, such as the phenolic intake manifold and valve block for dual clutch transmissions. The chapter also characterizes the most recent developments in new materials, including long glass phenolic molding compounds and carbon fiber reinforced phenolic molding compounds exhibiting a 10-20-fold increase in Charpy impact strength when compared to short fiber filled materials. The role of fatigue testing and fatigue fracture behavior presents some insight into long-term reliability and durability of glass-filled phenolic molding compounds. A section on new technology outlines the important factors to consider in modeling phenolic parts by finite element analysis and flow simulation.
The compound ethers of glycerin
International Nuclear Information System (INIS)
In this chapter of book authors describe several methods of receiving of compound ethers of glycerin. The important technic significance have compound glycerin ether and nitric acid. This compound receive by reaction of glycerin with fuming nitric acid
Compound management beyond efficiency.
Burr, Ian; Winchester, Toby; Keighley, Wilma; Sewing, Andreas
Codeveloping alongside chemistry and in vitro screening, compound management was one of the first areas in research recognizing the need for efficient processes and workflows. Material management groups have centralized, automated, miniaturized and, importantly, found out what not to do with compounds. While driving down cost and improving quality in storage and processing, researchers still face the challenge of interfacing optimally with changing business processes, in screening groups, and with external vendors and focusing on biologicals in many companies. Here we review our strategy to provide a seamless link between compound acquisition and screening operations and the impact of material management on quality of the downstream processes. Although this is driven in part by new technologies and improved quality control within material management, redefining team structures and roles also drives job satisfaction and motivation in our teams with a subsequent positive impact on cycle times and customer feedback. PMID:19502566
Fluorine-18 labelled compounds
International Nuclear Information System (INIS)
The work presented in this thesis deals with the problems involved in the adaption of reactor-produced fluorine-18 to the synthesis of 18F-labelled organic fluorine compounds. Several 18F-labelling reagents were prepared and successfully applied. The limitations to the synthetic possibilities of reactor-produced fluoride-18 become manifest in the last part of the thesis. An application to the synthesis of labelled aliphatic fluoro amino acids has appeared to be unsuccessful as yet, although some other synthetic approaches can be indicated. Seven journal articles (for which see the availability note) are used to compose the four chapters and three appendices. The connecting text gives a survey of known 18F-compounds and methods for preparing such compounds. (Auth.)
Compound semiconductor device physics
Tiwari, Sandip
This book provides one of the most rigorous treatments of compound semiconductor device physics yet published. A complete understanding of modern devices requires a working knowledge of low-dimensional physics, the use of statistical methods, and the use of one-, two-, and three-dimensional analytical and numerical analysis techniques. With its systematic and detailed**discussion of these topics, this book is ideal for both the researcher and the student. Although the emphasis of this text is on compound semiconductor devices, many of the principles discussed will also be useful to those inter
DEFF Research Database (Denmark)
Ravasio, Davide Antonio
Fungi produce a variety of volatile organic compounds (VOCs) during their primary or secondary metabolism and with a wide range of functions. The main focus of this research work has been put on flavour molecules that are produced during fermentation processes, mainly esters and alcohols derived...
Forecasting of superconducting compounds
International Nuclear Information System (INIS)
In forecasting new superconducting intermetallic compounds of the A15 and Mo3Se types most promising from the viewpoint of high critical temperature Tsub(c), high critical magnetic fields Hsub(c), and high critical currents and in estimating their transition temperature it is proposed to apply cybernetic methods of computer learning
Directory of Open Access Journals (Sweden)
Fernanda Viana da Silva Leonardo
Full Text Available Quinone compounds are largely generated at extractive fraction of the woods in a complex and variable biological system. The literature has indications for many segments from food industry to pharmaceutical industry. Within the field of industrial use of wood, they are less desirable since they are treated only as incidental substances in production strings of pulp, paper, charcoal, and sawmill. In spite of its small amount, compared to other chemical compounds called essential, these substances have received special attention from researchers revealing a diverse range of offerings to market products textiles, pharmaceuticals, colorants, and other polymers, for which are being tested and employed. Quinones are found in fungi, lichens, and mostly in higher plants. Tectona grandis, usually called teak, is able to biosynthesize anthraquinones, which is a quinone compound, byproduct of secondary metabolism. This species provides wood that is much prized in the furniture sector and can also be exploited for metabolites to supply the market in quinone compounds and commercial development of new technologies, adding value to the plantations of this species within our country.
Directory of Open Access Journals (Sweden)
A. M. Nasukhova
Full Text Available In article the review of the initial stage of researches of natural polyacetylene compounds is resulted. The high reactionary ability leading to fast oxidation and degradation of these compounds, especially at influence of Uf-light, oxygen of air, pH and other factors, has caused the serious difficulties connected with an establishment of structure and studying of their physical and chemical properties. Therefore the greatest quantity of works of this stage is connected with studying of essential oils of plants from families Apiaceae, Araliaceae, Asteraceae, Campanulaceae, Olacaceae, Pittosporaceae and Santalaceae where have been found out, basically, diacetylene compounds. About development of physical and chemical methods of the analysis of possibility of similar researches have considerably extended. More than 2000 polyacetylenes are known today, from them more than 1100 are found out in plants fam. Asteraceae. Revolution in the field of molecular biology has allowed to study processes of biosynthesis of these compounds intensively.
Stabilization of labelled compounds
International Nuclear Information System (INIS)
This invention concerns a composition including a labelled compound, and the vitamin B 12. This vitamin gives a red colour to the solution and stabilize it radiochemically, allowing to transport the solution at ambient temperature and a storage at 4 degrees celsius. (N.C.). 5 refs
Compound floating pivot micromechanisms
Garcia, Ernest J.
A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use compound floating pivot structures to attain far greater tilt angles than are practical using other micromechanical techniques. The new mechanisms are also capable of bi-directional tilt about multiple axes.
Fissibility of compound nuclei
Iwata, Yoritaka
Collisions between $^{248}$Cm and $^{48}$Ca are systematically investigated by time-dependent density functional calculations with evaporation prescription. Depending on the incident energy and impact parameter, fusion, deep-inelastic and fission events are expected to appear. In this paper, a microscopic method of calculating the fissibility of compound nuclei is presented.
Compound semiconductor device modelling
Miles, Robert
Compound semiconductor devices form the foundation of solid-state microwave and optoelectronic technologies used in many modern communication systems. In common with their low frequency counterparts, these devices are often represented using equivalent circuit models, but it is often necessary to resort to physical models in order to gain insight into the detailed operation of compound semiconductor devices. Many of the earliest physical models were indeed developed to understand the 'unusual' phenomena which occur at high frequencies. Such was the case with the Gunn and IMPATI diodes, which led to an increased interest in using numerical simulation methods. Contemporary devices often have feature sizes so small that they no longer operate within the familiar traditional framework, and hot electron or even quantum mechanical models are required. The need for accurate and efficient models suitable for computer aided design has increased with the demand for a wider range of integrated devices for operation at...
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Shekar S
Full Text Available Odontomas are considered to be hamartomas rather than a true neoplasm. They consist chiefly of enamel and dentin, with variable amount of pulp and cementum when fully developed. They are generally asymptomatic and are included under the benign calcified odontogenic tumors. They are usually discovered on routine radiographic examination. Eruption of an odontoma in the oral cavity is rare. Peripheral compound odontomas arise extraosseously and have a tendency to exfoliate. In this article we are reporting a case of a 15-year-old girl with peripheral compound odontoma, with a single rudimentary tooth-like structure in the mandibular right second molar region, which is about to be exfoliated. Its eruption in the oral cavity and location in the mandibular posterior region is associated with aplasia of the mandibular right second molar, making it an interesting case for reporting.
Endocrine disrupting compounds
DEFF Research Database (Denmark)
Bøgh, I B; Christensen, P; Dantzer, V;
With the growing concern that environmental chemicals might impair human and animal fertility, it is important to investigate the possible influence of these substances on sexual differentiation and genital development of mammals. Many of these substances are suspected to interfere with endocrine...... of alkylphenols, these are disseminated in the environment with sewage sludge, and domestic animals and humans are likely to be exposed via the food chain. Using the pig as an in vivo model, we studied the effect of intrauterine exposure to tertiary octylphenol (OP) on essential reproductive...... usefulness of in vivo animal or embryo models for the evaluation of possible consequences of human exposure to endocrine disrupting compounds is discussed. Furthermore, possible consequences of exposure to endocrine disrupting compounds for the embryo transfer industry are addressed....
Organic compounds in meteorites
Lawless, J. G.
Recent studies of carbonaceous chondrites provide evidence that certain organic compounds are indigenous and the result of an abiotic, chemical synthesis. The results of several investigators have established the presence of amino acids and precursors, mono- and dicarboxylic acids, N-heterocycles, and hydrocarbons as well as other compounds. For example, studies of the Murchison and Murray meteorites have revealed the presence of at least 40 amino acids with nearly equal abundances of D and L isomers. The population consists of both protein and nonprotein amino acids including a wide variety of linear, cyclic, and polyfunctional types. Results show a trend of decreasing concentration with increasing carbon number, with the most abundant being glycine (41 n Moles/g). These and other results to be reviewed provide persuasive support for the theory of chemical evolution and provide the only natural evidence for the protobiological subset of molecules from which life on earth may have arisen.
Compound Chondrules fused Cold
Hubbard, Alexander
About 4-5% of chondrules are compound: two separate chondrules stuck together. This is commonly believed to be the result of the two component chondrules having collided shortly after forming, while still molten. This allows high velocity impacts to result in sticking. However, at T ~ 1100K, the temperature below which chondrules collide as solids (and hence usually bounce), coalescence times for droplets of appropriate composition are measured in tens of seconds. Even at 1025K, at which temperature theory predicts that the chondrules must have collided extremely slowly to have stuck together, the coalescence time scale is still less than an hour. These coalescence time scales are too short for the collision of molten chondrules to explain the observed frequency of compound chondrules. We suggest instead a scenario where chondrules stuck together in slow collisions while fully solid; and the resulting chondrule pair was subsequently briefly heated to a temperature in the range of 900-1025K. In that temperatur...
Hydrogen in compound semiconductors
Energy Technology Data Exchange (ETDEWEB)
Haller, E.E.
Progress in the understanding of hydrogen and its interactions in III/V and II/VI compound semiconductors is reviewed. Donor, acceptor and deep level passivation is well established in III/V compounds based on electrical measurements and on spectroscopic studies. The hydrogen donor levels in GaAs and GaP are estimated to lie near E{sub v}+0.5 eV and E{sub v}+0.3 eV, respectively. Arsenic acceptors have been passivated by hydrogen in CdTe and the very first nitrogen-hydrogen local vibrational model spectra in ZnSe have been reported. This long awaited result may lead to an explanation for the poor activation of nitrogen acceptors in ZnSe grown by techniques which involve high concentrations of hydrogen.
International Nuclear Information System (INIS)
Since the end of World War II there has been a tremendous increase in the number of compounds that have been synthesized with radioactive or stable isotopes. They have found application in many diverse fields, so much so, that hardly a single area in pure and applied science has not benefited. Not surprisingly it has been reflected in appearance of related publications. The early proceedings of the Symposia on Advances in Trace Methodology were soon followed by various Euratom sponsored meetings in which methods of preparing and storing labelled compounds featured prominently. In due course a resurgence of interest in stable isotopes, brought about by their greater availability (also lower cost) and partly by development of new techniques such as gas chromatography - mass spectrometry (gc-ms), led to the publication of proceedings of several successful conferences. More recently conferences dealing with the synthesis and applications of isotopes and isotopically labelled compounds have been established on a regular basis. In addition to the proceedings of conferences and journal publications individuals left their mark by producing definitive texts, usually on specific nuclides. Only the classic two volume publication of Murray and Williams (Organic syntheses with isotopes, New York 1985), now over 30 years old and out of print, attempted to do justice to several nuclides. With the large amount of work that has been undertaken since then it seems unlikely that an updated edition could be produced. The alternative strategy was to ask scientists currently active to review specific areas and this is the approach adopted in the present series of monographs. In this way it is intended to cover the broad advances that have been made in the synthesis and applications of isotopes and isotopically labelled compounds in the physical and biomedical sciences. (author). refs.; figs.; tabs
Skoglund, Maria
This research project examined how to treat raw oat material for oat-based food products in order to sustain or increase the levels of phenolic compounds. The focus was mainly on the avenanthramides, which are potentially health beneficial bioactive components found exclusively in oats. A proposed enzymatic decrease in avenanthramide levels when non heat-treated milled oats are steeped in water was investigated. The decrease was strongly suggested to be caused by a polyphenol oxidase. Althoug...
Compound chondrules fused cold
Hubbard, Alexander
About 4-5% of chondrules are compound: two separate chondrules stuck together. This is commonly believed to be the result of the two component chondrules having collided shortly after forming, while still molten. This allows high velocity impacts to result in sticking. However, at T ∼ 1100 K, the temperature below which chondrules collide as solids (and hence usually bounce), coalescence times for droplets of appropriate composition are measured in tens of seconds. Even at 1025 K, at which temperature theory predicts that the chondrules must have collided extremely slowly to have stuck together, the coalescence time scale is still less than an hour. These coalescence time scales are too short for the collision of molten chondrules to explain the observed frequency of compound chondrules. We suggest instead a scenario where chondrules stuck together in slow collisions while fully solid; and the resulting chondrule pair was subsequently briefly heated to a temperature in the range of 900-1025 K. In that temperature window the coalescence time is finite but long, covering a span of hours to a decade. This is particularly interesting because those temperatures are precisely the critical window for thermally ionized MRI activity, so compound chondrules provide a possible probe into that vital regime.
Directory of Open Access Journals (Sweden)
Shlomo Shamai (Shitz
Full Text Available This paper considers the compound wiretap channel, which generalizes Wyner's wiretap model to allow the channels to the (legitimate receiver and to the eavesdropper to take a number of possible states. No matter which states occur, the transmitter guarantees that the receiver decodes its message and that the eavesdropper is kept in full ignorance about the message. The compound wiretap channel can also be viewed as a multicast channel with multiple eavesdroppers, in which the transmitter sends information to all receivers and keeps the information secret from all eavesdroppers. For the discrete memoryless channel, lower and upper bounds on the secrecy capacity are derived. The secrecy capacity is established for the degraded channel and the semideterministic channel with one receiver. The parallel Gaussian channel is further studied. The secrecy capacity and the secrecy degree of freedom (s.d.o.f. are derived for the degraded case with one receiver. Schemes to achieve the s.d.o.f. for the case with two receivers and two eavesdroppers are constructed to demonstrate the necessity of a prefix channel in encoder design. Finally, the multi-antenna (i.e., MIMO compound wiretap channel is studied. The secrecy capacity is established for the degraded case and an achievable s.d.o.f. is given for the general case.
Directory of Open Access Journals (Sweden)
Kramer Gerhard
Full Text Available Abstract This paper considers the compound wiretap channel, which generalizes Wyner's wiretap model to allow the channels to the (legitimate receiver and to the eavesdropper to take a number of possible states. No matter which states occur, the transmitter guarantees that the receiver decodes its message and that the eavesdropper is kept in full ignorance about the message. The compound wiretap channel can also be viewed as a multicast channel with multiple eavesdroppers, in which the transmitter sends information to all receivers and keeps the information secret from all eavesdroppers. For the discrete memoryless channel, lower and upper bounds on the secrecy capacity are derived. The secrecy capacity is established for the degraded channel and the semideterministic channel with one receiver. The parallel Gaussian channel is further studied. The secrecy capacity and the secrecy degree of freedom ( are derived for the degraded case with one receiver. Schemes to achieve the for the case with two receivers and two eavesdroppers are constructed to demonstrate the necessity of a prefix channel in encoder design. Finally, the multi-antenna (i.e., MIMO compound wiretap channel is studied. The secrecy capacity is established for the degraded case and an achievable is given for the general case.
Institute of Scientific and Technical Information of China (English)
Konrad; J.; M.; PAPIS; Joerg; F.; LOEFFLER; Peter; J.; UGGOWITZER
'Compound casting'simplifies joining processes by directly casting a metallic melt onto a solid metal substrate. A continuously metallurgic transition is very important for industrial applications, such as joint structures of spaceframe constructions in transport industry. In this project, 'compound casting' of light metals is investigated, aiming at weight-saving. The substrate used is a wrought aluminium alloy of type AA5xxx, containing magnesium as main alloying element. The melts are aluminium alloys, containing various alloying elements (Cu, Si, Zn), and magnesium. By replacing the natural oxygen layer with a zinc layer, the inherent wetting difficulties were avoided, and compounds with flawless interfaces were successfully produced (no contraction defects, cracks or oxides). Electron microscopy and EDX investigations as well as optical micrographs of the interfacial areas revealed their continu- ously metallic constitution. Diffusion of alloying elements leads to heat-treatable microstructures in the vicinity of the joining interfaces in Al-Al couples. This permits significant variability of mechanical properties. Without significantly cutting down on wettability, the formation of low-melting intermetallic phases (Al3Mg2 and Al12Mg17 IMPs) at the interface of Al-Mg couples was avoided by applying a protective coating to the substrate.
Institute of Scientific and Technical Information of China (English)
Konrad J.M.PAPIS; Joerg F.LOEFFLER; Peter J.UGGOWITZER
'Compound casting'simplifies joining processes by directly casting a metallic melt onto a solid metal substrate. A continuously metallurgic transition is very important for industrial applications, such as joint structures of spaceframe constructions in transport industry. In this project, 'compound casting' of light metals is investigated, aiming at weight-saving. The substrate used is a wrought aluminium alloy of type AA5xxx, containing magnesium as main alloying element. The melts are aluminium alloys, containing various alloying elements (Cu, Si, Zn), and magnesium. By replacing the natural oxygen layer with a zinc layer, the inherent wetting difficulties were avoided, and compounds with flawless interfaces were successfully produced (no contraction defects, cracks or oxides). Electron microscopy and EDX investigations as well as optical micrographs of the interfacial areas revealed their continu-ously metallic constitution. Diffusion of alloying elements leads to heat-treatable microstructures in the vicinity of the joining interfaces in Al-Al couples. This permits significant variability of mechanical properties. Without significantly cutting down on wettability, the formation of low-melting intermetallic phases (Al3Mg2 and AI12Mg17 IMPs) at the interface of Al-Mg couples was avoided by applying a protec-tive coating to the substrate.
Islam, Md Nazmul; Khalil, Md Ibrahim; Islam, Md Asiful; Gan, Siew Hua
There is a wealth of information about the nutritional and medicinal properties of honey. However, honey may contain compounds that may lead to toxicity. A compound not naturally present in honey, named 5-hydroxymethylfurfural (HMF), may be formed during the heating or preservation processes of honey. HMF has gained much interest, as it is commonly detected in honey samples, especially samples that have been stored for a long time. HMF is a compound that may be mutagenic, carcinogenic and cytotoxic. It has also been reported that honey can be contaminated with heavy metals such as lead, arsenic, mercury and cadmium. Honey produced from the nectar of Rhododendron ponticum contains alkaloids that can be poisonous to humans, while honey collected from Andromeda flowers contains grayanotoxins, which can cause paralysis of limbs in humans and eventually leads to death. In addition, Melicope ternata and Coriaria arborea from New Zealand produce toxic honey that can be fatal. There are reports that honey is not safe to be consumed when it is collected from Datura plants (from Mexico and Hungary), belladonna flowers and Hyoscamus niger plants (from Hungary), Serjania lethalis (from Brazil), Gelsemium sempervirens (from the American Southwest), Kalmia latifolia, Tripetalia paniculata and Ledum palustre. Although the symptoms of poisoning due to honey consumption may differ depending on the source of toxins, most common symptoms generally include dizziness, nausea, vomiting, convulsions, headache, palpitations or even death. It has been suggested that honey should not be considered a completely safe food. PMID:24214851
Morphology of uranium compounds
International Nuclear Information System (INIS)
Uranium metal is being used as nuclear fuel for Indian Research Reactors. During production of U metal various intermediate compounds of uranium are being processed. Physical, chemical properties of these compounds are important in overall processing rate and conversion determination. As no systematic data on morphology of these compounds were available, study was conducted to record the morphology of various U-compounds which are important in production of ceramic and metallic U-fuel for reactors. Most important intermediates were found to be ammonium diuranate (ADU) and uranium oxide (UO3/UO2). Morphology of these powders controls their flowability required for further material movement through different equipment, surface area required for chemical reactivity of powder, carryover losses occurred during gas solid counter current reaction and tap density required for effective capacity determination. ADU particle basically consists of primary platelets of 250-500 nm width and of 500-1000 nm length. These primary platelets form primary agglomerates. These agglomerates look like woollen balls or balls or cauliflower and primary agglomerates are also connected with each other to form secondary agglomerates. The basic morphology of ADU is maintained in UO3 even after calcination at high temperature. Pores are generated at the surface of platelet of UO3 due to release of gaseous reaction products during calcination. As temperature increases more pores are generated and sintering also starts. Specific surface area of UO3, produced by the calcination of ammonium di-urinate is generally a function of two competing processes: generation of surface area due to generation of pores because of the evolution of gaseous products (NH3, H2O vapour) and the loss of surfaces due to sintering. As a results surface area increases with calcination temperature due to generation of pores and then reduces. It has also been observed that morphology of the compounds are very much processing
Xenobiotic organic compounds in wastewater
DEFF Research Database (Denmark)
Eriksson, Eva; Baun, Anders; Henze, Mogens; Ledin, Anna
Information regarding the contents of xenobiotic organic compounds (XOCs) in wastewater is limited, but it has been shown that at least 900 different compounds / compound groups could potentially be present in grey wastewater. Analyses of Danish grey wastewater revealed the presence of several...... hundred of XOCs, among them mainly originating from hygiene products: chlorophenols, detergents and phthalates. Several compounds not deriving from hygiene products were also identified e.g. flame-retardants and drugs. A environmental hazard identification showed that a large number of compounds with high...... aquatic toxicity were present and that data for environmental fate could only be retrieved for about half of the compounds....
Nomenclature on an inorganic compound
International Nuclear Information System (INIS)
This book contains eleven chapters : which mention nomenclature of an inorganic compound with introduction and general principle on nomenclature of compound. It gives the description of grammar for nomenclature such as brackets, diagonal line, asterisk, and affix, element, atom and groups of atom, chemical formula, naming by stoichiometry, solid, neutral molecule compound, ion, a substituent, radical and name of salt, oxo acid and anion on introduction and definition of oxo acid, coordination compound like symbol of stereochemistry , boron and hydrogen compound and related compound.
Xenobiotic organic compounds in wastewater
DEFF Research Database (Denmark)
Eriksson, Eva; Baun, Anders; Henze, Mogens;
Information regarding the contents of xenobiotic organic compounds (XOCs) in wastewater is limited, but it has been shown that at least 900 different compounds / compound groups could potentially be present in grey wastewater. Analyses of Danish grey wastewater revealed the presence of several...... hundred of XOCs, among them mainly originating from hygiene products: chlorophenols, detergents and phthalates. Several compounds not deriving from hygiene products were also identified e.g. flame-retardants and drugs. A environmental hazard identification showed that a large number of compounds with high...... aquatic toxicity were present and that data for environmental fate could only be retrieved for about half of the compounds....
Stevens, Mark A.; Handschuh, Robert F.; Lewicki, David G.
The Offset Compound Gear Drive is an in-line, discrete, two-speed device utilizing a special offset compound gear that has both an internal tooth configuration on the input end and external tooth configuration on the output end, thus allowing it to mesh in series, simultaneously, with both a smaller external tooth input gear and a larger internal tooth output gear. This unique geometry and offset axis permits the compound gear to mesh with the smaller diameter input gear and the larger diameter output gear, both of which are on the same central, or primary, centerline. This configuration results in a compact in-line reduction gear set consisting of fewer gears and bearings than a conventional planetary gear train. Switching between the two output ratios is accomplished through a main control clutch and sprag. Power flow to the above is transmitted through concentric power paths. Low-speed operation is accomplished in two meshes. For the purpose of illustrating the low-speed output operation, the following example pitch diameters are given. A 5.0 pitch diameter (PD) input gear to 7.50 PD (internal tooth) intermediate gear (0.667 reduction mesh), and a 7.50 PD (external tooth) intermediate gear to a 10.00 PD output gear (0.750 reduction mesh). Note that it is not required that the intermediate gears on the offset axis be of the same diameter. For this example, the resultant low-speed ratio is 2:1 (output speed = 0.500; product of stage one 0.667 reduction and stage two 0.750 stage reduction). The design is not restricted to the example pitch diameters, or output ratio. From the output gear, power is transmitted through a hollow drive shaft, which, in turn, drives a sprag during which time the main clutch is disengaged.
Compound semiconductor integrated circuits
Vu, Tho T
This is the book version of a special issue of the International Journal of High Speed Electronics and Systems , reviewing recent work in the field of compound semiconductor integrated circuits. There are fourteen invited papers covering a wide range of applications, frequencies and materials. These papers deal with digital, analog, microwave and millimeter-wave technologies, devices and integrated circuits for wireline fiber-optic lightwave transmissions, and wireless radio-frequency microwave and millimeter-wave communications. In each case, the market is young and experiencing rapid growth
Boyle, Timothy J.
A titanium alkoxide composition is provided, as represented by the chemical formula (OC.sub.6H.sub.5N).sub.2Ti(OC.sub.6H.sub.5NH.sub.2).sub.2. As prepared, the compound is a crystalline substance with a hexavalent titanium atom bonded to two OC.sub.6H.sub.5NH.sub.2 groups and two OC.sub.6H.sub.5N groups with a theoretical molecular weight of 480.38, comprising 60.01% C, 5.04% H and 11.66% N.
Catalytic properties of niobium compounds
International Nuclear Information System (INIS)
The catalytic activity and selectivity of niobium compounds including oxides, salts, organometallic compounds and others are outlined. The application of these compounds as catalysts to diversified reactions is reported. The nature and action of niobium catalysts are characteristic and sometimes anomalous, suggesting the necessity of basic research and the potential use as catalysts for important processes in the chemical industry. (Author)
Goldenphilicity: Luminescent gold compounds
International Nuclear Information System (INIS)
In the solids and molecules different types of bonds are presented depending on the involved atoms, covalent bonds are common among elements of open shell, where more bond orbitals are filled than anti bond orbitals. It is expected that ionic bonds among closed shell atoms which have charges of opposite sign. Bonds type Van der Waals are presented among molecules which have a bipolar moment. It would not be expected bonds among zero charge species, or more generally with the same nominal charge and in any case the attractive forces would be very small. In fact it is expected that two metallic cations to be repelled each other. There recently is evidence that in organic or organometallic compounds could exist attractive interactions between two cations of the d8 -d10 -s2 families. These bonds are weak but stronger than those of Van der Waals. They are compared with the hydrogen bonds. In this work it was reviewed some examples in which the goldenphilicity plays an important role in the luminescence that the gold complexes present. Examples of mono, bi and trinuclear and the structures that these organometallic compounds could take are examined. (Author)
Semiconducting III-V compounds
Hilsum, C; Henisch, Heinz R
Semiconducting III-V Compounds deals with the properties of III-V compounds as a family of semiconducting crystals and relates these compounds to the monatomic semiconductors silicon and germanium. Emphasis is placed on physical processes that are peculiar to III-V compounds, particularly those that combine boron, aluminum, gallium, and indium with phosphorus, arsenic, and antimony (for example, indium antimonide, indium arsenide, gallium antimonide, and gallium arsenide).Comprised of eight chapters, this book begins with an assessment of the crystal structure and binding of III-V compounds, f
International Nuclear Information System (INIS)
The goal is: Not more emission of volatile organic compounds (VOCs) than necessary. The items discussed in this presentation are the VOCs, how to calculate emission of VOCs, how to reduce or avoid them, and different recovery processes. The largest source of Norwegian emissions of non methane VOCs (NMVOCs) is offshore loading of raw petroleum. Emissions of VOCs should be reduced mainly for two reasons: (1) on sunny days NMVOCs may react with NOx to form ozon and smog close to the surface, (2) ozone and smog close to the surface may be harmful to plants and animals, and they are hazardous to human health. As for the calculation of VOC emissions, the VOCON project will release the calculation program HCGASS in 1999. This project is a cooperative project headed by SINTEF/Marintek
Synthesis of labeled compounds
International Nuclear Information System (INIS)
Intermediate compounds labeled with 13C included methane, sodium cyanide, methanol, ethanol, and acetonitrile. A new method for synthesizing 15N-labeled 4-ethylsulfonyl-1-naphthalene-sulfonamide was developed. Studies were conducted on pathways to oleic-1-13C acid and a second pathway investigated was based on carbonation of 8-heptadecynylmagnesium bromide with CO2 to prepare sterolic acid. Biosynthetic preparations included glucose-13C from starch isolated from tobacco leaves following photosynthetic incubation with 13CO2 and galactose-13C from galactosylglycerol-13C from kelp. Research on growth of organisms emphasized photosynthetic growth of algae in which all cellular carbon is labeled. Preliminary experiments were performed to optimize the growth of Escherichia coli on sodium acetate-13C
Microoptical telescope compound eye.
Duparré, Jacques; Schreiber, Peter; Matthes, André; Pshenay-Severin, Ekaterina; Bräuer, Andreas; Tünnermann, Andreas; Völkel, Reinhard; Eisner, Martin; Scharf, Toralf
A new optical concept for compact digital image acquisition devices with large field of view is developed and proofed experimentally. Archetypes for the imaging system are compound eyes of small insects and the Gabor-Superlens. A paraxial 3x3 matrix formalism is used to describe the telescope arrangement of three microlens arrays with different pitch to find first order parameters of the imaging system. A 2mm thin imaging system with 21x3 channels, 70 masculinex10 masculine field of view and 4.5mm x 0.5mm image size is optimized and analyzed using sequential and non-sequential raytracing and fabricated by microoptics technology. Anamorphic lenses, where the parameters are a function of the considered optical channel, are used to achieve a homogeneous optical performance over the whole field of view. Captured images are presented and compared to simulation results. PMID:19494951
International Nuclear Information System (INIS)
The Tritium System Test Assembly (TSTA), at the Los Alamos Scientific Laboratory, is intended to demonstrate realistic fuel supply and cleanup scenarios for future fusion reactors. The vacuum pumps must be capable of handling large quantities of reactor exhaust gases consisting largely of mixtures of hydrogen and helium isotopes. Cryocondensing pumps will not pump helium at 4.2 K; while cryosorption pumps using molecular sieves or charcoal have good helium pumping speed, the adsorbent clogs with condensed hydrogen while pumping mixtures of both. A solution to this problem is a compound design whereby the first stage condenses the hydrogen and the second, or sorption, stage pumps the helium. The TSTA pump designed at Lawrence Livermore National Laboratory uses argon gas to cryotrap the helium in the helium-hydrogen mixture. The argon is sprayed directly onto the 4.2 K surface at a rate proportional to the helium flow rate, permitting continuous pumping of the helium-hydrogen mixtures in a single-stage pump. However, the possibility of differential desorption as a first stage in the TSTA gas separation cycle required the inclusion of a first-stage hydrogen isotope condenser. The design, performance, and operating characteristics are discussed
Compounding in synthetic aperture imaging.
Hansen, Jens Munk; Jensen, Jørgen Arendt
A method for obtaining compound images using synthetic aperture data is investigated using a convex array transducer. The new approach allows spatial compounding to be performed for any number of angles without reducing the frame rate or temporal resolution. This important feature is an intrinsic property of how the compound images are constructed using synthetic aperture data and an improvement compared with how spatial compounding is obtained using conventional methods. The synthetic aperture compound images are created by exploiting the linearity of delay-and-sum beamformation for data collected from multiple spherical emissions to synthesize multiple transmit and receive apertures, corresponding to imaging the tissue from multiple directions. The many images are added incoherently, to produce a single compound image. Using a 192-element, 3.5-MHz, λ-pitch transducer, it is demonstrated from tissue-phantom measurements that the speckle is reduced and the contrast resolution improved when applying synthetic aperture compound imaging. At a depth of 4 cm, the size of the synthesized apertures is optimized for lesion detection based on the speckle information density. This is a performance measure for tissue contrast resolution which quantifies the tradeoff between resolution loss and speckle reduction. The speckle information density is improved by 25% when comparing synthetic aperture compounding to a similar setup for compounding using dynamic receive focusing. The cystic resolution and clutter levels are measured using a wire phantom setup and compared with conventional application of the array, as well as to synthetic aperture imaging without compounding. If the full aperture is used for synthetic aperture compounding, the cystic resolution is improved by 41% compared with conventional imaging, and is at least as good as what can be obtained using synthetic aperture imaging without compounding. PMID:23007781
Organic Compounds in Carbonaceous Meteorites
Cooper, Grorge
Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the best-characterized carbonaceous meteorite with respect to organic chemistry. The study of its organic compounds has related principally to aqueous meteorite parent body chemistry and compounds of potential importance for the origin of life. Among the classes of organic compounds found in Murchison are amino acids, amides, carboxylic acids, hydroxy acids, sulfonic acids, phosphonic acids, purines and pyrimidines (Table 1). Compounds such as these were quite likely delivered to the early Earth in asteroids and comets. Until now, polyhydroxylated compounds (polyols), including sugars (polyhydroxy aldehydes or ketones), sugar alcohols, sugar acids, etc., had not been identified in Murchison. Ribose and deoxyribose, five-carbon sugars, are central to the role of contemporary nucleic acids, DNA and RNA. Glycerol, a three-carbon sugar alcohol, is a constituent of all known biological membranes. Due to the relative lability of sugars, some researchers have questioned the lifetime of sugars under the presumed conditions on the early Earth and postulated other (more stable) compounds as constituents of the first replicating molecules. The identification of potential sources and/or formation mechanisms of pre-biotic polyols would add to the understanding of what organic compounds were available, and for what length of time, on the ancient Earth.
For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.
Cytotoxic Compounds from Zanthoxylum Americanum
Institute of Scientific and Technical Information of China (English)
Four pyranocoumarins: dipetaline, alloxanthoxyletin, xanthoxyletin, and xanthyletin, and two lignans: sesamin and asarinin were isolated from the northern prickly ash, Zanthoxylum americanum. To varying degrees, all six compounds inhibited the incorporation of tritiated thymidine into human leukemia (HL-60) cells and the inhibitory effect was dependent on the structures of the isolated compounds.
Bilayer Effects of Antimalarial Compounds.
Directory of Open Access Journals (Sweden)
Nicole B Ramsey
Full Text Available Because of the perpetual development of resistance to current therapies for malaria, the Medicines for Malaria Venture developed the Malaria Box to facilitate the drug development process. We tested the 80 most potent compounds from the box for bilayer-mediated effects on membrane protein conformational changes (a measure of likely toxicity in a gramicidin-based stopped flow fluorescence assay. Among the Malaria Box compounds tested, four compounds altered membrane properties (p< 0.05; MMV007384 stood out as a potent bilayer-perturbing compound that is toxic in many cell-based assays, suggesting that testing for membrane perturbation could help identify toxic compounds. In any case, MMV007384 should be approached with caution, if at all.
Optimizing Synthetic Aperture Compound Imaging
DEFF Research Database (Denmark)
Hansen, Jens Munk; Jensen, Jørgen Arendt
Spatial compound images are constructed from synthetic aperture data acquired using a linear phased-array transducer. Compound images of wires, tissue, and cysts are created using a method, which allows both transmit and receive compounding without any loss in temporal resolution. Similarly to...... optimal for lesion detection. Synthetic aperture data are acquired from unfocused emissions and 154 compound images are constructed by synthesizing different aperture configurations with more or less compounding, all maintaining a constant resolution across depth corresponding to an f-number of 2.0 for...... transmit and receive. The same configurations are used for scanning a phantom with cysts, and it is demonstrated how an improved cysts contrast follows from an aperture configuration, which gives a higher value for the performance measure extracted from the phantom without cysts. A correlation value R = 0...
Characterization of Sulfur Compounds in MTBE
Mingqing Wu; Chunyan Chang; Tao Li; Jian Zhou; Liping Zhao
A study is carried out on chemical constitution of sulfur compounds in MTBE and their formation mechanisms. These sulfur compounds are classified into three types: common sulfur compounds, newly formed sulfur compounds, and high boiling sulfur compounds. Common sulfur compounds which include mercaptans, low molecule sulfides and disulfides, are directly from C4, one of the stocks for production of MTBE. The newly formed sulfur compounds, with one sulfur atom and five or more total carbon atom...
Nomenclature on an organic compound (I)
International Nuclear Information System (INIS)
This book is about nomenclature on an organic compound, which includes introduction with general principle on nomenclature on compounds it describes hydrocarbon like terpene hydrocarbon, basic heterocyclic organic compound including carbon, hydrogen, oxygen, nitrogen, halogen, sulfur, selenium and tellurium such as nomenclature system, halogen derivatives, alcohol and phenol derivatives, compound with sulfur, amino, nitroso and nitro compound, amino radical ion, azo and azoxy compound, compound including an atom group, hydrazine and derivatives.
Regulation of Compound Leaf Development
Directory of Open Access Journals (Sweden)
Yuan Wang
Full Text Available Leaf morphology is one of the most variable, yet inheritable, traits in the plant kingdom. How plants develop a variety of forms and shapes is a major biological question. Here, we discuss some recent progress in understanding the development of compound or dissected leaves in model species, such as tomato (Solanum lycopersicum, Cardamine hirsuta and Medicago truncatula, with an emphasis on recent discoveries in legumes. We also discuss progress in gene regulations and hormonal actions in compound leaf development. These studies facilitate our understanding of the underlying regulatory mechanisms and put forward a prospective in compound leaf studies.
Oxidation-reduction properties of americium, curium, berkelium, californium, einsteinium and fermium, and thermodynamic consequences for the 5f series
International Nuclear Information System (INIS)
The amalgamation of 5f elements from Am to Fm has been studied by using 241Am, 244Cm, 249Bk, 249Cf, 252Cf, 253Es, 254Es, 252Fm and 255Fm with two electrochemical methods, radiocoulometry and radiopolarography, perfectly adapted to investigate extremely diluted solutions when the concentration of electroactive species is as low as 10-16M. The theory of radiocoulometry has been developed in the general cases of reversible and irreversible electrode process. It has been used to interpret the experimental data on the kinetic curves of amalgamation, and to estimate the standard rate constant of the electrode process in complexing medium (citric). On the other hand the radiopolarographic method has been applied to study the mechanism of reduction at the dropping mercury electrode of cations M3+ in aqueous medium to the metal M with formation of amalgam. The results are exploited into two directions: 1- Acquisition of some data concerning the oxidation-reduction properties of elements from Am to Fm. Therefore the standard electrode E0 [M(III-0)] potentials for Bk, Cf and Es, and the standard electrode E0 [M(II-0)] potential for Fm are estimated and the relative stability of each oxidation state (from II to VII) of 5f elements is discussed; 2- Acquisition of unknown thermodynamic data on transcalifornium elements. Correlations between 4f and 5f elements are precised and some divergences appear for the second half of 4f and 5f series (i.e. for 65<=Z<=71 and 97<=Z<=103)
Evaluation of thermal neutron cross-sections and resonance integrals of protactinium, americium, curium, and berkelium isotopes
International Nuclear Information System (INIS)
Data on the thermal neutron fission and capture cross-sections as well as their corresponding resonance integrals are reviewed and analysed. The data are classified according to the form of neutron spectra under investigation. The weighted mean values of the cross-sections and resonance integrals for every type of neutron spectra were adopted as evaluated data. (author). 87 refs, 2 tabs
Crystallographic properties of fertilizer compounds
Energy Technology Data Exchange (ETDEWEB)
Frazier, A.W.; Dillard, E.F.; Thrasher, R.D.; Waerstad, K.R.; Hunter, S.R.; Kohler, J.J.; Scheib, R.M.
This bulletin is a compilation of crystallographic data collected at NFERC on 450 fertilizer-related compounds. In TVA's fertilizer R and D program, petrographic examination, XRD, and infrared spectroscopy are combined with conventional chemical analysis methods in identifying the individual compounds that occur in fertilizer materials. This handbook brings together the results of these characterization studies and supplemental crystallographic data from the literature. It is in one-compound-per-page, loose-leaf format, ordered alphabetically by IUPAC name. Indexes provided include IUPAC name, formula, group, alternate formula, synonyms, x-ray data, optical data. Tables are given for solids, compounds in commercial MAP and DAP, and matrix materials in phosphate rock.
The precipitation of vanadium compounds
International Nuclear Information System (INIS)
The results of a study on the chemistry of the precipitation process of vanadium compounds in sulfuric media are presented, in order to recover the vanadium contained in the ore from Campo Alegre de Lourdes (Bahia-Brazil). (Author)
Optimization of compound gear pump
Institute of Scientific and Technical Information of China (English)
This paper introduces the performances of compound gear pump. Based on the target of having the smallest mass per unit volume, the paper established a mathematical model of optimization, and obtained the results of optimization of the pump.
Fourth symposium on macrocyclic compounds
International Nuclear Information System (INIS)
Both theoretical and experimental aspects of the properties and behavior of synthetic and naturally occurring macrocyclic compounds are covered in this symposium. This document contains abstracts of the papers
DEFF Research Database (Denmark)
Andreasen, Jørgen; Eskemose Andersen, Jørgen
The compound house has long provided the accomodation required by low income households in West African cities. In Kumasi, Ghana, evidence suggests that no new compounds are being built. Instead, the city is being ringed by relatively affluent villa-style development while neighbourhoods dominated...... the neighbourhood unity is a challenge for urban planners. However they represent good value for money, cost little to build, suit traditional inheritence patterns, allow independent life at low cost and allow sharing of services with a finite and known group (albeit within a potential conflictive...... characteristics of compound housing and analyses the advantages and disadvantages of life within such housing in Kumasi. Issues of privacy, image and communal life are usually cited by occupants dissatiesfied with life in compound houses, and the difficulty of extending them without spoiling the open spaces and...
Compounding in synthetic aperture imaging
DEFF Research Database (Denmark)
Hansen, J. M.; Jensen, J. A.
A method for obtaining compound images using synthetic aperture data is investigated using a convex array transducer. The new approach allows spatial compounding to be performed for any number of angles without reducing the frame rate or temporal resolution. This important feature is an intrinsic...... from multiple spherical emissions to synthesize multiple transmit and receive apertures, corresponding to imaging the tissue from multiple directions. The many images are added incoherently, to produce a single compound image. Using a 192-element, 3.5-MHz, λ-pitch transducer, it is demonstrated from...... tissue-phantom measurements that the speckle is reduced and the contrast resolution improved when applying synthetic aperture compound imaging. At a depth of 4 cm, the size of the synthesized apertures is optimized for lesion detection based on the speckle information density. This is a performance...
Quality control of labelled compounds
International Nuclear Information System (INIS)
Some advantages and disadvantages of methods used for quality control of organic labelled compounds (131I, 14C) are shortly discussed. The methods used are electrophoresis, ultraviolet and infrared spectrometry, radiogas and thin-layer chromatography. (author)
Phenolic Compounds in Brassica Vegetables
Directory of Open Access Journals (Sweden)
Pablo Velasco
Full Text Available Phenolic compounds are a large group of phytochemicals widespread in the plant kingdom. Depending on their structure they can be classified into simple phenols, phenolic acids, hydroxycinnamic acid derivatives and flavonoids. Phenolic compounds have received considerable attention for being potentially protective factors against cancer and heart diseases, in part because of their potent antioxidative properties and their ubiquity in a wide range of commonly consumed foods of plant origin. The Brassicaceae family includes a wide range of horticultural crops, some of them with economic significance and extensively used in the diet throughout the world. The phenolic composition of Brassica vegetables has been recently investigated and, nowadays, the profile of different Brassica species is well established. Here, we review the significance of phenolic compounds as a source of beneficial compounds for human health and the influence of environmental conditions and processing mechanisms on the phenolic composition of Brassica vegetables.
DEFF Research Database (Denmark)
Jespersen, Søren Kragh; Wilhjelm, Jens Erik; Sillesen, Henrik
This paper reports on a scanning technique, denoted multi-angle compound imaging (MACI), using spatial compounding. The MACI method also contains elements of frequency compounding, as the transmit frequency is lowered for the highest beam angles in order to reduce grating lobes. Compared to...... conventional B-mode imaging MACI offers better defined tissue boundaries and lower variance of the speckle pattern, resulting in an image with reduced random variations. Design and implementation of a compound imaging system is described, images of rubber tubes and porcine aorta are shown and effects on...... visualization are discussed. The speckle reduction is analyzed numerically and the results are found to be in excellent agreement with existing theory. An investigation of detectability of low-contrast lesions shows significant improvements compared to conventional imaging. Finally, possibilities for improving...
Third Symposium on Macrocyclic Compounds
International Nuclear Information System (INIS)
At the Third Symposium on Macrocyclic Compounds there were sessions on facilitated transport, analytical applications, organic synthesis and reactions, phase transfer catalysis, and metal complexation. Abstracts of the individual presentations are included
Structural Library of Natural Compounds
Directory of Open Access Journals (Sweden)
Subhash Chandra Bose Kotte
Full Text Available Natural products with biological activity are of considerable interest to drug discovery community and a structural library of such compounds serves as data set for insilico experiments to predict the target specific activity before screening them in in-vitro experiments. This work leverages open source scientific tools to create a database of such compounds library in Structure Data Format with 3D coordinates which in turn may be used as an input file for various applications.
Phenolic Compounds in Brassica Vegetables
Pablo Velasco; María Elena Cartea; Pilar Soengas; Marta Francisco
Phenolic compounds are a large group of phytochemicals widespread in the plant kingdom. Depending on their structure they can be classified into simple phenols, phenolic acids, hydroxycinnamic acid derivatives and flavonoids. Phenolic compounds have received considerable attention for being potentially protective factors against cancer and heart diseases, in part because of their potent antioxidative properties and their ubiquity in a wide range of commonly consumed foods of plant origin. The...
Transplacental Transfer of Perfluorinated Compounds
Adhikari, M.
Humans are exposed to chemical carcinogens and endocrine disruptors for instances through environment and diet they consume. Special attention should be paid to pregnant mothers in whom consumption of any harmful compounds can lead to adverse effects in a new born baby as it is believed that these compounds pass through the placenta. The developing foetus is vulnerable to toxic and teratogenic effects and the prenatal exposure of chemicals might lead to developmental changes or even increase ...
Sulfated compounds from marine organisms.
Kornprobst, J M; Sallenave, C; Barnathan, G
More than 500 sulfated compounds have been isolated from marine organisms so far but most of them originate from two phyla only, Spongia and Echinodermata. The sulfated compounds are presented according to the phyla they have been identified from and to their chemical structures. Biological activities, when available, are also given. Macromolecules have also been included in this review but without structural details. PMID:9530808
Antitumor compounds from marine actinomycetes.
Salas, José A.; Carmen Méndez; Carlos Olano
Chemotherapy is one of the main treatments used to combat cancer. A great number of antitumor compounds are natural products or their derivatives, mainly produced by microorganisms. In particular, actinomycetes are the producers of a large number of natural products with different biological activities, including antitumor properties. These antitumor compounds belong to several structural classes such as anthracyclines, enediynes, indolocarbazoles, isoprenoides, macrolides, non-ribosomal pept...
Cancer chemoprevention by natural compounds
スズキ, マスミ; Masumi, SUZUI
There is growing interest in the use of natural compounds for the treatment and prevention of a wide variety of diseases, including cancer. Several herb-derived components are currently evaluated in preclinical studies as potential cancer chemopreventive agents. We have recently found that several herbal plants in the Ryukyu Islands, or any other natural compound, have a potential chemopreventive effect on biomarkers of colon carcinogenesis and a growth inhibitory effect on human cancer cells...
Insertion compounds of uranium oxides
International Nuclear Information System (INIS)
Insertion compounds are formed by the intercalation of an electropositive species, such as hydrogen or an alkali metal, with minimal structural rearrangement of the host oxide. In this report a review of the measured structural, thermodynamic and transport properties of the insertion compounds of α-U3O8, α-UO3, γ-UO3, δ-UO3 and related systems is given. (author)
Antitumor Immunity and Dietary Compounds
Directory of Open Access Journals (Sweden)
Annalise R. Smith
Full Text Available The mechanisms by which natural dietary compounds exert their antitumor effects have been the focus of a large number of research efforts in recent years. Induction of apoptosis by inhibition of cell proliferative pathways is one of the common means of cell death employed by these dietary compounds. However, agents that can activate an antitumor immune response in addition to a chemotherapeutic effect may be useful adjuvants or alternative therapies for the treatment of cancer. The focus of this review is to highlight representative dietary compounds, namely Withania somnifera, Panax ginseng, curcumin and resveratrol with special emphasis on their antitumor immune mechanism of action. Each of these dietary compounds and their sources has a history of safe human use as food or in herbal medicine traditions, potentially making them ideal therapeutics. Here we report the recent advances in the cellular immune mechanisms utilized by these compounds to induce antitumor immunity. Taken together, these findings provide a new perspective for exploiting novel dietary compounds as chemoimmunotherapeutic anti-cancer agents.
Host compounds for red phosphorescent OLEDs
Xia, Chuanjun; Cheon, Kwang -Ohk
Novel compounds containing a triphenylene moiety linked to an .alpha..beta. connected binaphthyl ring system are provided. These compounds have surprisingly good solubility in organic solvents and are useful as host compounds in red phosphorescent OLEDs.
Method for purifying bidentate organophosphorus compounds
Schulz, Wallace W.
Bidentate organophosphorus compounds useful for extracting actinide elements from acidic nuclear waste solutions are purified of undesirable acidic impurities by contacting the compounds with ethylene glycol which preferentially extracts the impurities found in technical grade bidentate compounds.
Nomenclature on an organic compound (II)
International Nuclear Information System (INIS)
This book deals with nomenclature on an organic compound except carbon, hydrogen, oxygen, nitrogen, halogen, sulfur, selenium and tellurium. It mentions introduction, nomenclature system, coordination compound, an organo-metallic compound, homogeneous chains and rings with regular form of heteroatoms, organic compound including arsenic, phosphorus and bismuth, stereochemistry, nomenclature of compound related a natural substance, modified compound in to an isotope. The last chapter has recommendation on general principle and instruction for nomenclature.
Energy Technology Data Exchange (ETDEWEB)
Papis, Konrad; Uggowitzer, Peter; Loeffler, Joerg [ETH Zurich, Laboratory of Metal Physics and Technology, Zurich (Switzerland)
'Compound casting' is a process where a melt is cast onto or around a solid metallic 'insert'. It is the realization of a simple joining procedure for light metals aimed at weight-saving. Difficulties inherent in joining aluminium are its natural oxide layer and the formation of intermetallic phases. In this project, both the solid substrate and the melt used are aluminium alloys containing various alloying elements (Cu, Si, Zn in the melt, Mg in the substrate). Compounds with flawless interfaces (no contraction defects, no oxides) were successfully produced by replacing the oxide layer with a zinc layer. This was accomplished by pickling the substrate in a solution containing zincate ions, implying a redox reaction by which zinc is deposited in its metallic form. The composition and mechanical properties of the compounds' interfacial regions were investigated by SEM/EDX and microhardness measurements following the 'compound casting' process and successive heat treatments. DICTRA calculations were carried out to simulate the diffusion processes at the interface. The results from the mechanical characterization were compared to the simulations, the conclusion being that diffusion of alloying elements led to precipitation hardening of the compound.
Particle formation of gas-phase silicon compounds and aromatic compounds by light or electron irradiation
International Nuclear Information System (INIS)
A number of silicon compounds and aromatic compounds form particles under UV light or electron beam irradiation in the gas phase. Carbonyl compounds, halogen compounds and some aromatic compounds act as initiators for photo-induced particle formation of silicon compounds. (author)
Biodegradation of halogenated organic compounds.
Chaudhry, G R; Chapalamadugu, S
In this review we discuss the degradation of chlorinated hydrocarbons by microorganisms, emphasizing the physiological, biochemical, and genetic basis of the biodegradation of aliphatic, aromatic, and polycyclic compounds. Many environmentally important xenobiotics are halogenated, especially chlorinated. These compounds are manufactured and used as pesticides, plasticizers, paint and printing-ink components, adhesives, flame retardants, hydraulic and heat transfer fluids, refrigerants, solvents, additives for cutting oils, and textile auxiliaries. The hazardous chemicals enter the environment through production, commercial application, and waste. As a result of bioaccumulation in the food chain and groundwater contamination, they pose public health problems because many of them are toxic, mutagenic, or carcinogenic. Although synthetic chemicals are usually recalcitrant to biodegradation, microorganisms have evolved an extensive range of enzymes, pathways, and control mechanisms that are responsible for catabolism of a wide variety of such compounds. Thus, such biological degradation can be exploited to alleviate environmental pollution problems. The pathways by which a given compound is degraded are determined by the physical, chemical, and microbiological aspects of a particular environment. By understanding the genetic basis of catabolism of xenobiotics, it is possible to improve the efficacy of naturally occurring microorganisms or construct new microorganisms capable of degrading pollutants in soil and aquatic environments more efficiently. Recently a number of genes whose enzyme products have a broader substrate specificity for the degradation of aromatic compounds have been cloned and attempts have been made to construct gene cassettes or synthetic operons comprising these degradative genes. Such gene cassettes or operons can be transferred into suitable microbial hosts for extending and custom designing the pathways for rapid degradation of recalcitrant
Czech Academy of Sciences Publication Activity Database
Haindl, Michal; Havlíček, Vojtěch
Los Alamitos : IEEE Computer Society CPS, 2010, s. 1792-1795. ISBN 978-1-4244-7542-1. ISSN 1051-4651. [20th International Conference on Pattern Recognition ICPR 2010. Istanbul (TR), 23.08.2010-26.08.2010] R&D Projects: GA MŠk 1M0572; GA ČR GA102/08/0593 Grant ostatní: GA MŠk(CZ) 2C06019 Institutional research plan: CEZ:AV0Z10750506 Keywords : compound Markov random field * bidirectional texture function Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/2010/RO/haindl-a compound mrf texture model.pdf
Method to extract uranium compounds
International Nuclear Information System (INIS)
The uranium compounds present in gangue of phosphate ores are also to be determined and extracted with the proposed method. The gangue-water mixture in phosphate extraction is to be displaced, according to the invention, by a component which selectively dissolves the uranium compounds out of the gangue. The enriched solution is separated off and processed. Weak acids (e.g. phosphoric acid, acetre acid, citric acid), lyes (e.g. ammonium carbonate, soda) or salts (e.g. sodium hydrogen phosphate, NaHCO3 tartrates) are named as solution components. (UWI)
Antiprotozoal compounds from Asparagus africanus
DEFF Research Database (Denmark)
Oketch-Rabah, H A; Dossaji, S F; Christensen, S B;
Two antiprotozoal compounds have been isolated from the roots of Asparagus africanus Lam. (Liliaceae), a new sapogenin, 2 beta, 12 alpha-dihydroxy-(25R)-spirosta-4,7-dien-3-one (1), which was named muzanzagenin, and the lignan (+)-nyasol (2), (Z)-(+)-4,4'-(3-ethenyl-1-propene-1,3-diyl)-bisphenol.......Two antiprotozoal compounds have been isolated from the roots of Asparagus africanus Lam. (Liliaceae), a new sapogenin, 2 beta, 12 alpha-dihydroxy-(25R)-spirosta-4,7-dien-3-one (1), which was named muzanzagenin, and the lignan (+)-nyasol (2), (Z)-(+)-4,4'-(3-ethenyl-1-propene-1,3-diyl...
The structures of binary compounds
Hafner, J; Jensen, WB; Majewski, JA; Mathis, K; Villars, P; Vogl, P; de Boer, FR
- Up-to-date compilation of the experimental data on the structures of binary compounds by Villars and colleagues. - Coloured structure maps which order the compounds into their respective structural domains and present for the first time the local co-ordination polyhedra for the 150 most frequently occurring structure types, pedagogically very helpful and useful in the search for new materials with a required crystal structure. - Crystal co-ordination formulas: a flexible notation for the interpretation of solid-state structures by chemist Bill Jensen. - Recent important advances in unders
Halogenated Compounds from Marine Algae
Directory of Open Access Journals (Sweden)
Amélia Pilar Rauter
Full Text Available Marine algae produce a cocktail of halogenated metabolites with potential commercial value. Structures exhibited by these compounds go from acyclic entities with a linear chain to complex polycyclic molecules. Their medical and pharmaceutical application has been investigated for a few decades, however other properties, such as antifouling, are not to be discarded. Many compounds were discovered in the last years, although the need for new drugs keeps this field open as many algal species are poorly screened. The ecological role of marine algal halogenated metabolites has somehow been overlooked. This new research field will provide valuable and novel insight into the marine ecosystem dynamics as well as a new approach to comprehending biodiversity. Furthermore, understanding interactions between halogenated compound production by algae and the environment, including anthropogenic or global climate changes, is a challenging target for the coming years. Research of halogenated metabolites has been more focused on macroalgae than on phytoplankton. However, phytoplankton could be a very promising material since it is the base of the marine food chain with quick adaptation to environmental changes, which undoubtedly has consequences on secondary metabolism. This paper reviews recent progress on this field and presents trends on the role of marine algae as producers of halogenated compounds.
Moessbauer spectroscopy in neptunium compounds
Energy Technology Data Exchange (ETDEWEB)
Nakamoto, Tadahiro; Nakada, Masami; Masaki, Nobuyuki; Saeki, Masakatsu [Japan Atomic Energy Research Inst., Tokyo (Japan)
Moessbauer effects are observable in seven elements of actinides from {sup 232}Th to {sup 247}Cm and Moesbauer spectra have been investigated mainly with {sup 237}Np and {sup 238}U for the reasons of availability and cost of materials. This report describes the fundamental characteristics of Moessbauer spectra of {sup 237}Np and the correlation between the isomer shift and the coordination number of Np(V) compounds. The isomer shifts of Np(V) compounds had a tendency to increase as an increase of coordination number and the isomer shifts of Np(V) compounds showed broad distribution as well as those of Np(VI) but {delta} values of the compounds with the same coordination number were distributed in a narrow range. The {delta} values of Np(VI) complexes with O{sub x} donor set suggest that the Np atom in its hydroxide (NpO{sub 2}(OH){center_dot}4H{sub 2}O)might have pentagonal bipyramidal structure and at least, pentagonal and hexagonal bipyramidal structures might coexist in its acetate and benzoate. Really, such coexistence has been demonstrated in its nitrate, (NpO{sub 2}){sub 2}(NO{sub 3}){sub 2}{center_dot}5H{sub 2}O. (M.N.)
DEFF Research Database (Denmark)
Smith, Viktor; Barratt, Daniel; Zlatev, Jordan
Danish food market and using Danish NNCs. Specifically, we addressed a highly productive type of compound food names where the modifier denotes a geographical entity and the head denotes a type of food, e.g. Hawaii pizza. Our findings contribute new evidence to central issues of (cognitive) linguistic...
Organophosphorus Compounds in Organic Electronics.
Shameem, Muhammad Anwar; Orthaber, Andreas
This Minireview describes recent advances of organophosphorus compounds as opto-electronic materials in the field of organic electronics. The progress of (hetero-) phospholes, unsaturated phosphanes, and trivalent and pentavalent phosphanes since 2010 is covered. The described applications of organophosphorus materials range from single molecule sensors, field effect transistors, organic light emitting diodes, to polymeric materials for organic photovoltaic applications. PMID:27276233
Instability of viscoelastic compound jets
Ye, Han-Yu; Yang, Li-Jun; Fu, Qing-Fei
This paper investigates the axisymmetric instability of a viscoelastic compound jet, for which the constitutive relation is described by the Oldroyd B model. It is found that a viscoelastic compound jet is more unstable than a Newtonian compound jet, regardless of whether the viscoelastic compound jet is inner-Newtonian-outer-viscoelastic, inner-viscoelastic-outer-Newtonian, or fully viscoelastic. It is also found that an increase in the stress relaxation time of the inner or outer fluid renders the jet more unstable, while an increase in the time constant ratio makes the jet less unstable. An analysis of the energy budget of the destabilization process is performed, in which a formulation using the relative rate of change of energy is adopted. The formulation is observed to provide a quantitative analysis of the contribution of each physical factor (e.g., release of surface energy and viscous dissipation) to the temporal growth rate. The energy analysis reveals the mechanisms of various trends in the temporal growth rate, including not only how the growth rate changes with the parameters, but also how the growth rate changes with the wavenumber. The phenomenon of the dispersion relation presenting two local maxima, which occurred in previous research, is explained by the present energy analysis.
Fission Dynamics of Compound Nuclei
Iwata, Yoritaka; Heinz, Sophia
Collisions between $^{248}$Cm and $^{48}$Ca are systematically investigated by time-dependent density functional calculations with evaporation prescription. Depending on the incident energy and impact parameter, fusion, deep-inelastic and quasi-fission events are expected to appear. In this paper, possible fission dynamics of compound nuclei is presented.
Students' Categorizations of Organic Compounds
Domin, Daniel S.; Al-Masum, Mohammad; Mensah, John
Categorization is a fundamental psychological ability necessary for problem solving and many other higher-level cognitive tasks. In organic chemistry, students must establish groupings of different chemical compounds in order not only to solve problems, but also to understand course content. Classic models of categorization emphasize similarity as…
Lohnas, Lynn J.; Kahana, Michael J.
According to the retrieved context theory of episodic memory, the cue for recall of an item is a weighted sum of recently activated cognitive states, including previously recalled and studied items as well as their associations. We show that this theory predicts there should be compound cuing in free recall. Specifically, the temporal contiguity…
An epoxide modified polymerisable compound
International Nuclear Information System (INIS)
The description is given of an epoxide modified polymerisable compound. It includes a mixture of the following reactive substances; a vinyled carboxylic acid which is acrylic or methacrylic acid; an aliphatic epoxide; a diepoxide and a modifier containing a reagent group that is a carboxylic acid; a phenol, an alcohol, a carboxylic acid amide or a carboxylic acid halogenide
Olive oil phenolic compounds affect the release of aroma compounds.
Genovese, Alessandro; Caporaso, Nicola; Villani, Veronica; Paduano, Antonello; Sacchi, Raffaele
Twelve aroma compounds were monitored and quantified by dynamic headspace analysis after their addition in refined olive oil model systems with extra virgin olive oil (EVOO) biophenols to simulate EVOO aroma. The influence of polyphenols on aroma release was studied under simulated mouth conditions by using human saliva, and SPME-GC/MS analysis. While few differences were observed in orthonasal assay (without saliva), interesting results were obtained for retronasal aroma. Biophenols caused generally the lowest headspace release of almost all volatile compounds. However, only ethyl esters and linalool concentrations were significantly lower in retronasal than orthonasal assay. Saliva also caused higher concentration of hexanal, probably due to hydroperoxide lyase (HPL) action on linoleyl hydroperoxides. Epicatechin was compared to EVOO phenolics and the behaviour was dramatically different, likely to be due to salivary protein-tannin binding interactions, which influenced aroma headspace release. These results were also confirmed using two extra virgin olive oils. PMID:25794752
Fe organoiron compounds. Pt. B11
International Nuclear Information System (INIS)
The chapter of compounds with ligands bonded by five carbon atoms deals with one 5L ligand, one 5L ligands and additional 1L ligands. In this chapter, there are different type compounds or complexes with iron containing carbonyl nitroxyl. The chapter of compounds with two CO ligands present the organoiron compounds with halide, where we find chemical properties, physical properties, analysis, adducts formation with halogen. In the last chapters, different compound with oxygen, nitrogen and their mechanism is discussed. (AB)
Heuristics for chemical compound matching.
Hattori, Masahiro; Okuno, Yasushi; Goto, Susumu; Kanehisa, Minoru
We have developed an efficient algorithm for comparing two chemical compounds, where the chemical structure is treated as a 2D graph consisting of atoms as vertices and covalent bonds as edges. Based on the concept of functional groups in chemistry, 68 atom types (vertex types) are defined for carbon, nitrogen, oxygen, and other atomic species with different environments, which has enabled detection of biochemically meaningful features. Maximal common subgraphs of two graphs can be found by searching for maximal cliques in the association graph, and we have introduced heuristics to accelerate the clique finding. Our heuristic procedure is controlled by some adjustable parameters. Here we applied our procedure to the latest KEGG/LIGAND database with different sets of parameters, and demonstrated the correlation of parameters in our algorithm with the distribution of similarity scores and/or the execution time. Finally, we showed the effectiveness of our heuristics for compound pairs along metabolic pathways. PMID:15706529
Microstructural degradation in compound tubes
Energy Technology Data Exchange (ETDEWEB)
Salonen, J.; Auerkari, P. [VTT Manufacturing Technology, Espoo (Finland)
In order to quantify microstructural degradation at high temperatures, samples of SA 210 / AISI 304 L compound tube material were annealed in the temperature range 540-720 deg C for 1 to 1 000 hours. The hardness of the annealed material was measured and the micro structure of the samples was investigated with optical and scanning electron microscopy. Microstructural degradation was characterised by the carbide structure in the ferritic-pearlitic base material and by the depth of decarburised and carburised zones of the compound tube interface. The observed changes were quantified in terms of their time and temperature dependence and diffusion coefficients of the process. The results can be used in estimating the extent of thermal exposure of high-temperature components after long-term service or after incidences of overheating. (orig.) (4 refs.)
Bacterial Degradation of Aromatic Compounds
Directory of Open Access Journals (Sweden)
Qing X. Li
Full Text Available Aromatic compounds are among the most prevalent and persistent pollutants in the environment. Petroleum-contaminated soil and sediment commonly contain a mixture of polycyclic aromatic hydrocarbons (PAHs and heterocyclic aromatics. Aromatics derived from industrial activities often have functional groups such as alkyls, halogens and nitro groups. Biodegradation is a major mechanism of removal of organic pollutants from a contaminated site. This review focuses on bacterial degradation pathways of selected aromatic compounds. Catabolic pathways of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene are described in detail. Bacterial catabolism of the heterocycles dibenzofuran, carbazole, dibenzothiophene, and dibenzodioxin is discussed. Bacterial catabolism of alkylated PAHs is summarized, followed by a brief discussion of proteomics and metabolomics as powerful tools for elucidation of biodegradation mechanisms.
Duparré, Jacques; Dannberg, Peter; Schreiber, Peter; Bräuer, Andreas; Tünnermann, Andreas
An artificial compound-eye objective fabricated by micro-optics technology is adapted and attached to a CMOS sensor array. The novel optical sensor system with an optics thickness of only 0.2 mm is examined with respect to resolution and sensitivity. An optical resolution of 60 x 60 pixels is determined from captured images. The scaling behavior of artificial compound-eye imaging systems is analyzed. Cross talk between channels fabricated by different technologies is evaluated, and the influence on an extension of the field of view by addition of a (Fresnel) diverging lens is discussed. The lithographic generation of opaque walls between channels for optical isolation is experimentally demonstrated. PMID:15929282
Compounds in food packaging materials
DEFF Research Database (Denmark)
Rosenmai, Anna Kjerstine
Food contact materials (FCMs) are sources of food contamination and human chemical exposure. Some chemicals in these materials are known to cause adverse effects, but many are poorly characterized for their potential toxicological hazards making risk assessment a challenge. The aim of the project...... were tested in vitro, active extracts were fractionated and tested in vitro, tentative identification was performed in active fractions, and tentatively identified compounds were tested in vitro and quantified in the extract. BPA analogues generally led to similar estrogenic and antiandrogenic effects...... in vitro compared to BPA. However, the BPA analogue BPS caused less marked effects on most of these endpoints, but led to a more pronounced effects on progestagen levels compared to BPA. Likewise, the effects on corticoid levels in the H295R steroidogenesis assay differed between the six compounds...
Bioactive compounds from Carissa spinarum.
Wangteeraprasert, Ruchira; Lipipun, Vimolmas; Gunaratnam, Mekala; Neidle, Stephen; Gibbons, Simon; Likhitwitayawuid, Kittisak
In our continuing efforts to find new antiherpetic agents from plants, an extract prepared from the stems of Carissa spinarum L. was found to possess appreciable activity against herpes simplex viruses (HSV I and II). A chemical study of this plant was then initiated, and this led to the isolation of 12 compounds, including a coumarin, two cardiac glycosides and nine lignans. These isolated compounds were evaluated for several biological activities, including antiherpetic, cytotoxic, antioxidant and antibacterial effects. The cardiac glycoside evomonoside was found to be the only antiherpetic principle, showing moderate activity against herpes simplex virus types I and II in the inactivation method. The lignans (-)-carinol, (-)-carissanol and (-)-nortrachelogenin exhibited cytotoxicity against breast (MCF7) and lung (A549) cancer cells. Moderate anti-DPPH free radical activity was observed for all the lignans. None of the isolates showed antibacterial activity. PMID:22308099
[Compound at Takalafiya, c.1939
Showing two girls spinning yarn in a compound. The photograph is part of a series of British Official photographs (Crown Copyright Reserved) issued under the general title 'Sleeping sickness experiment is pattern for progress in rural Africa'. The photograph has two captions stuck on the reverse. The first reads: 'The British Government is carrying out a successful and interesting experiment in Nigeria, to beat that great menace to African life, Sleeping Sickness. The town of Anchau, cent...
The formation of new compounds
Gasparoli, A.
The formation of new compounds The study of model systems allows us to reconstruct the complex mosaic of reactions which make up the frying process. In particular such systems, if made up of single oils or their components, verify the transformation of the triglyceride matrix by thermo-oxidizing treatment. Should this then have added specific substrates (protein, starch) they reconstruct the oil-substrate interaction and the influence of the same substrate in the transformation. The contribut...
Polymer-solvent molecular compounds
Guenet, Jean-Michel
Crystallisable polymers represent a large share of the polymers used for manufacturing a wide variety of objects, and consequently have received continuous attention from scientists these past 60 years. Molecular compounds from crystallisable polymers, particularly from synthetic polymers, are receiving growing interest due to their potential application in the making of new materials such as multiporous membranes capable of capturing large particles as well as small pollutant molecules. The present book gives a detailed description of these promising systems. The first chapter
Quantitative analysis of endogenous compounds.
Thakare, Rhishikesh; Chhonker, Yashpal S; Gautam, Nagsen; Alamoudi, Jawaher Abdullah; Alnouti, Yazen
Accurate quantitative analysis of endogenous analytes is essential for several clinical and non-clinical applications. LC-MS/MS is the technique of choice for quantitative analyses. Absolute quantification by LC/MS requires preparing standard curves in the same matrix as the study samples so that the matrix effect and the extraction efficiency for analytes are the same in both the standard and study samples. However, by definition, analyte-free biological matrices do not exist for endogenous compounds. To address the lack of blank matrices for the quantification of endogenous compounds by LC-MS/MS, four approaches are used including the standard addition, the background subtraction, the surrogate matrix, and the surrogate analyte methods. This review article presents an overview these approaches, cite and summarize their applications, and compare their advantages and disadvantages. In addition, we discuss in details, validation requirements and compatibility with FDA guidelines to ensure method reliability in quantifying endogenous compounds. The standard addition, background subtraction, and the surrogate analyte approaches allow the use of the same matrix for the calibration curve as the one to be analyzed in the test samples. However, in the surrogate matrix approach, various matrices such as artificial, stripped, and neat matrices are used as surrogate matrices for the actual matrix of study samples. For the surrogate analyte approach, it is required to demonstrate similarity in matrix effect and recovery between surrogate and authentic endogenous analytes. Similarly, for the surrogate matrix approach, it is required to demonstrate similar matrix effect and extraction recovery in both the surrogate and original matrices. All these methods represent indirect approaches to quantify endogenous compounds and regardless of what approach is followed, it has to be shown that none of the validation criteria have been compromised due to the indirect analyses. PMID
Dynamical Friction for Compound Bodies
Domínguez-Tenreiro, R.; Gómez-Flechoso, M. A.
In the framework of the fluctuation-dissipation approach to dynamical friction, we derive an expression giving the orbital energy exchange experienced by a compound body as it moves interacting with a non homogeneous discrete background. The body is assumed to be composed of particles endowed with a velocity spectrum and with a non homogeneous spatial distribution. The Chandrasekhar formula is recovered in the limit of a point-like satellite with zero velocity dispersion and infinite temperat...
Optimization of compound pressure cylinders
G.H. Majzoobi; A. Ghomi
Purpose: The purpose of this paper is optimization of the weight of compound cylinder for a specific pressure. The variables are shrinkage radius and shrinkage tolerance.Design/methodology/approach: SEQ technique for optimization, the finite element code, ANSYS for numerical simulation are employed to predict the optimized conditions. The results are verified by testing a number of closed end cylinders with various geometries, materials and internal pressures.Findings: The weight of a compoun...
Natural Compounds Modulating Mitochondrial Functions
Directory of Open Access Journals (Sweden)
Lara Gibellini
Full Text Available Mitochondria are organelles responsible for several crucial cell functions, including respiration, oxidative phosphorylation, and regulation of apoptosis; they are also the main intracellular source of reactive oxygen species (ROS. In the last years, a particular interest has been devoted to studying the effects on mitochondria of natural compounds of vegetal origin, quercetin (Qu, resveratrol (RSV, and curcumin (Cur being the most studied molecules. All these natural compounds modulate mitochondrial functions by inhibiting organelle enzymes or metabolic pathways (such as oxidative phosphorylation, by altering the production of mitochondrial ROS and by modulating the activity of transcription factors which regulate the expression of mitochondrial proteins. While Qu displays both pro- and antioxidant activities, RSV and Cur are strong antioxidant, as they efficiently scavenge mitochondrial ROS and upregulate antioxidant transcriptional programmes in cells. All the three compounds display a proapoptotic activity, mediated by the capability to directly cause the release of cytochrome c from mitochondria or indirectly by upregulating the expression of proapoptotic proteins of Bcl-2 family and downregulating antiapoptotic proteins. Interestingly, these effects are particularly evident on proliferating cancer cells and can have important therapeutic implications.
Bioactive compounds from northern plants.
Hohtola, Anja
Northern conditions are characterised by long days with much light and low temperatures during the growing season. It has been chimed that herbs and berries grown in the north are stronger tasting compared to those of southern origin. The compounds imparting aroma and color to berries and herbs are secondary metabolites which in plants mostly act as chemical means of defense. Recently, the production of secondary metabolites using plant cells has been the subject of expanding research. Light intensity, photoperiod and temperature have been reported to influence the biosynthesis of many secondary metabolites. Native wild aromatic and medicinal plant species of different families are being studied to meet the needs of raw material for the expanding industry of e.g., health-promoting food products known as nutraceutics. There are already a large number of known secondary compounds produced by plants, but the recent advances in modern extraction and analysis should enable many more as yet unknown compounds to be found, characterised and utilised. Rose root (Rhodiola rosea) is a perennial herbaceous plant which inhabits mountain regions throughout Europe, Asia and east coastal regions of North America. The extract made from the rhizomes acts as a stimulant like the Ginseng root. Roseroot has been categorized as an adaptogen and is reported to have many pharmacological properties. The biologically active components of the extract are salitroside tyrosol and cinnamic acid glycosides (rosavin, rosarin, rosin). Round-leaved sundew (Drosera rotundifolia L.) has circumboreal distribution. It inhabits nutrient-poor, moist and sunny areas such as peat bogs and wetlands. Sundew leaves are collected from the wild-type for various medicinal preparations and can be utilized in treating e.g., as an important "cough-medicine" for different respiratory diseases. The antimicrobial activity of extracts of aerial parts against various bacteria has been investigated. Drosera produces
Nomenclature of inorganic compounds. Principles and examples
International Nuclear Information System (INIS)
This text-book consist of eighteen parts: (1) Classification and nomenclature of elements; (2) Classification and nomenclature of chemical compounds; (3) Nomenclature systems; (4) Classification of chemical formulas; (5) Codified numerical prefixes; (6) General principles of nomenclature; (7) Binary compounds; (8) Neutral and cationic atomic groups terminated with -YL; (9) Acids; (10) Polynuclear acids; (11) Double salts and mixed forms of oxides and hydroxides; (12) Adducts; (13) Intermetallic compounds; (14) Isotopically modified compounds; (15) Coordination compounds; (16) Organometallic compounds and their derivatives; (17) Appendixes; (18) Used and recommended literature. This text-book is assigned for university students of the chemistry and related sciences.
Nitrogen Compounds in Radiation Chemistry
International Nuclear Information System (INIS)
Water radiolysis in presence of N2 is probably the topic the most controversy in the field of water radiolysis. It still exists a strong discrepancy between the different reports of ammonia formation by water radiolysis in presence of N2 and moreover in absence of oxygen there is no agreement on the formation or not of nitrogen oxide like NO2- and NO3-. These discrepancies come from multiple sources: - the complexity of the reaction mechanisms where nitrogen is involved - the experimental difficulties - and, the irradiation conditions. The aim of the workshop is to capitalize the knowledge needed to go further in simulations and understanding the problems caused (or not) by the presence of nitrogen / water in the environment of radioactive materials. Implications are evident in terms of corrosion, understanding of biological systems and atmospheric chemistry under radiation. Topics covered include experimental and theoretical approaches, application and fundamental researches: - Nitrate and Ammonia in radiation chemistry in nuclear cycle; - NOx in biological systems and atmospheric chemistry; - Formation of Nitrogen compounds in Nuclear installations; - Nitrogen in future power plant projects (Gen4, ITER...) and large particle accelerators. This document gathers the transparencies available for 7 of the presentations given at this workshop. These are: - H.E SIMS: 'Radiation Chemistry of Nitrogen Compounds in Nuclear Power Plant'; - G.R. DEY: 'Nitrogen Compounds Formation in the Radiolysis of Aqueous Solutions'; - C.E. VAUDEY et al.: 'Radiolytic corrosion of nuclear graphite studied with the dedicated gas irradiation cell of IPNL'; - J.L. BOUCHER: 'Roles and biosynthesis of NO in eukaryotes and prokaryotes'; - W.H. KOPPENOL: 'Chemistry of NOx'; - E. JANATA: 'Yield of OH in N2O saturated aqueous solution'; - V. DAUVOIS: 'Analytical strategy for the study of radiolysis gases'
Aroma compounds in fresh cut pomegranate arils.
Little published information exists regarding flavor and aroma compounds in pomegranate (Punica granatum). Although arils have fruity and sweet characteristics, we found no publications describing actual compounds responsible for their typical flavor. Since most commercial usage of pomegranates in...
Potts Compound Markovian Texture Model
Czech Academy of Sciences Publication Activity Database
Haindl, Michal; Remeš, Václav; Havlíček, Vojtěch
Piscataway : IEEE Press, 2012, s. 29-32. ISBN 978-1-4673-2216-4. [21st International Conference on Pattern Recognition (ICPR 2012). Tsukuba (JP), 11.11.2012-15.11.2012] R&D Projects: GA ČR GAP103/11/0335; GA ČR GA102/08/0593 Grant ostatní: CESNET(CZ) 409/2011 Institutional support: RVO:67985556 Keywords : texture * Markov random field Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/2012/RO/haindl-potts compound markov ian texture model.pdf
Thermodynamic data of intermetallic compounds
International Nuclear Information System (INIS)
The data are presented in the alphabetical order of the chemical symbol for the elements. Each table presents the data of a group of binary intermetallic compounds with a common first component. For example, Table 1 shows the data of all binaries of silver. The table lists the properties indicated. For completeness, the experimental methods used in obtaining the data are also listed in the remarks column. The units are kJ mol-1 for all energy quantities and J K-1 mol-1 for entropies. (author)
Hydrogen storage in molecular compounds
Mao, Wendy L.; Mao, Ho-kwang
At low temperature (T) and high pressure (P), gas molecules can be held in ice cages to form crystalline molecular compounds that may have application for energy storage. We synthesized a hydrogen clathrate hydrate, H2(H2O)2, that holds 50 g/liter hydrogen by volume or 5.3 wt %. The clathrate, synthesized at 200–300 MPa and 240–249 K, can be preserved to ambient P at 77 K. The stored hydrogen is released when the clathrate is warmed to 140 K at ambient P. Low T also stabilizes other molecular...
BTF Potts compound texture model
Czech Academy of Sciences Publication Activity Database
Haindl, Michal; Remeš, Václav; Havlíček, Vojtěch
Bellingham: SPIE-IS&T, 2015, 939807-1-939807-11. (Proceedings of SPIE. 9398). ISBN 978-1-62841-488-2. ISSN 0277-786X. [Electronic Imaging 2015. San Francisco (US), 08.02.2015-12.02.2015] R&D Projects: GA ČR(CZ) GA14-10911S; GA ČR(CZ) GA14-02652S Keywords : Texture * texture synthesis * compound Markov random field model * CAR model * Potts MRF * Voronoi mosaic Subject RIV: BD - Theory of Information http://library.utia.cas.cz/separaty/21015/RO/haindl-0443580.pdf
Volatile organic compound sensor system
Energy Technology Data Exchange (ETDEWEB)
Schabron, John F. (Laramie, WY); Rovani, Jr., Joseph F. (Laramie, WY); Bomstad, Theresa M. (Waxahachie, TX); Sorini-Wong, Susan S. (Laramie, WY); Wong, Gregory K. (Laramie, WY)
Generally, this invention relates to the development of field monitoring methodology for new substances and sensing chemical warfare agents (CWAs) and terrorist substances. It also relates to a portable test kit which may be utilized to measure concentrations of halogenated volatile organic compounds (VOCs) in the field. Specifically it relates to systems for reliably field sensing the potential presence of such items while also distinguishing them from other elements potentially present. It also relates to overall systems and processes for sensing, reacting, and responding to an indicated presence of such substance, including modifications of existing halogenated sensors and arrayed sensing systems and methods.
Two new acetylenic compounds from Asparagus officinalis.
Li, Xue-Mei; Cai, Jin-Long; Wang, Wen-Xiang; Ai, Hong-Lian; Mao, Zi-Chao
Two new acetylenic compounds, asparoffins A (1) and B (2), together with two known compounds, nyasol (3) and 3″-methoxynyasol (4), were isolated from stems of Asparagus officinalis. The structures of two new compounds were elucidated on the basis of detailed spectroscopic analyses (UV, IR, MS, 1D, and 2D NMR). All compounds were evaluated for their cytotoxicities against three human cancer cell lines. PMID:26558641
Semiconducting compounds and devices incorporating same
Energy Technology Data Exchange (ETDEWEB)
Marks, Tobin J.; Facchetti, Antonio; Boudreault, Pierre-Luc; Miyauchi, Hiroyuki
Disclosed are molecular and polymeric compounds having desirable properties as semiconducting materials. Such compounds can exhibit desirable electronic properties and possess processing advantages including solution-processability and/or good stability. Organic transistor and photovoltaic devices incorporating the present compounds as the active layer exhibit good device performance.
Low-molecular compounds of erythrocytes
Directory of Open Access Journals (Sweden)
O. O. Sorochan
Full Text Available Glucose and free amino acids levels in rats' blood plasma and erythrocytes hemolysate under carcinoma Geuren Т8 development as well as after introduction of Rhenium (III and сys-Platinum compounds were studied. The complex Rhenium (III compounds with organic ligands act as antioxidant and normalize the concentration of low-molecular compounds in erythrocytes under the carcinogenesis.
Five new bioactive compounds from Chenopodium ambrosioides.
Song, Kun; Zhang, Jian; Zhang, Peng; Wang, Hong-Qing; Liu, Chao; Li, Bao-Ming; Kang, Jie; Chen, Ruo-Yun
Five new bioactive compounds, chenopodiumamines A-D (1-4) and chenopodiumoside A (5), were isolated from the ethanol extract of Chenopodium ambrosioides. The structures of these compounds were elucidated by various spectroscopic means (UV, IR, HR-ESI-MS, 1D and 2D NMR). Compounds 1-3 had moderate antioxidant and anti-inflammatory activities. PMID:26001043
Superconductivity in graphite intercalation compounds
Energy Technology Data Exchange (ETDEWEB)
Smith, Robert P. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Weller, Thomas E.; Howard, Christopher A. [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom); Dean, Mark P.M. [Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973 (United States); Rahnejat, Kaveh C. [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom); Saxena, Siddharth S. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Ellerby, Mark, E-mail: email@example.com [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom)
Highlights: • Historical background of graphite intercalates. • Superconductivity in graphite intercalates and its place in the field of superconductivity. • Recent developments. • Relevant modeling of superconductivity in graphite intercalates. • Interpretations that pertain and questions that remain. - Abstract: The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s (Dresselhaus and Dresselhaus, 1981; Enoki et al., 2003). This paper recontextualizes the field in light of the discovery of superconductivity in CaC{sub 6} and YbC{sub 6} in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how these relate to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity, and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition.
Superconductivity in graphite intercalation compounds
International Nuclear Information System (INIS)
Highlights: • Historical background of graphite intercalates. • Superconductivity in graphite intercalates and its place in the field of superconductivity. • Recent developments. • Relevant modeling of superconductivity in graphite intercalates. • Interpretations that pertain and questions that remain. - Abstract: The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s (Dresselhaus and Dresselhaus, 1981; Enoki et al., 2003). This paper recontextualizes the field in light of the discovery of superconductivity in CaC6 and YbC6 in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how these relate to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity, and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition
Latent IBP Compound Dirichlet Allocation.
Archambeau, Cedric; Lakshminarayanan, Balaji; Bouchard, Guillaume
We introduce the four-parameter IBP compound Dirichlet process (ICDP), a stochastic process that generates sparse non-negative vectors with potentially an unbounded number of entries. If we repeatedly sample from the ICDP we can generate sparse matrices with an infinite number of columns and power-law characteristics. We apply the four-parameter ICDP to sparse nonparametric topic modelling to account for the very large number of topics present in large text corpora and the power-law distribution of the vocabulary of natural languages. The model, which we call latent IBP compound Dirichlet allocation (LIDA), allows for power-law distributions, both, in the number of topics summarising the documents and in the number of words defining each topic. It can be interpreted as a sparse variant of the hierarchical Pitman-Yor process when applied to topic modelling. We derive an efficient and simple collapsed Gibbs sampler closely related to the collapsed Gibbs sampler of latent Dirichlet allocation (LDA), making the model applicable in a wide range of domains. Our nonparametric Bayesian topic model compares favourably to the widely used hierarchical Dirichlet process and its heavy tailed version, the hierarchical Pitman-Yor process, on benchmark corpora. Experiments demonstrate that accounting for the power-distribution of real data is beneficial and that sparsity provides more interpretable results. PMID:26353244
Prebiotic Evolution of Nitrogen Compounds
Arrhenius, G.
Support from this four year grant has funded our research on two general problems. One involves attempts to model the abiotic formation of simple source compounds for functional biomolecules, their concentration from dilute state in the hydrosphere and, in several cases, surface induced reactions to form precursor monomers for bioactive end products (refs. 1-5). Because of the pervasiveness and antiquity of phosphate based biochemistry and the catalytic activity of RNA we have exploring the hypothesis of an RNA World as an early stage in the emergence of life. This concept is now rather generally considered, but has been questioned due to the earlier lack of an experimentally demonstrated successful scheme for the spontaneous formation of ribose phosphate, the key backbone molecule in RNA. That impediment has now been removed. This has been achieved by demonstrating probable sources of activated (condensed) highly soluble and strongly sorbed phosphates in nature (Refs. 1,2) and effective condensation of aldehyde phosphates to form ribose phosphate in high yield (ref.6), thereby placing the RNA World concept on a somewhat safer experimental footing. Like all work in this field these experiments are oversimplifications that largely ignore competing side reactions with other compounds expected to be present. None the less our choice of experimental conditions aim at selective processes that eliminate interfering reactions. We have also sought to narrow the credibility gap by simulating geophysically and geochemically plausible conditions surrounding the putative prebiotic reactions.
Corrosion Preventive Compounds Lifetime Testing
Hale, Stephanie M.; Kammerer, Catherine C.; Copp, Tracy L.
Lifetime Testing of Corrosion Preventive Compounds (CPCs) was performed to quantify performance in the various environments to which the Space Shuttle Orbiter is exposed during a flight cycle. Three CPCs are approved for use on the Orbiter: RD Calcium Grease, Dinitrol AV-30, and Braycote 601 EF. These CPCs have been rigorously tested to prove that they mitigate corrosion in typical environments, but little information is available on how they perform in the unique combination of the coastal environment at the launch pad, the vacuum of low-earth orbit, and the extreme heat of reentry. Currently, there is no lifetime or reapplication schedule established for these compounds that is based on this combination of environmental conditions. Aluminum 2024 coupons were coated with the three CPCs and exposed to conditions that simulate the environments to which the Orbiter is exposed. Uncoated Aluminum 2024 coupons were exposed to the environmental conditions as a control. Visual inspection and Electro- Impedance Spectroscopy (EIS) were performed on the samples in order to determine the effectiveness of the CPCs. The samples were processed through five mission life cycles or until the visual inspection revealed the initiation of corrosion and EIS indicated severe degradation of the coating.
Energy Technology Data Exchange (ETDEWEB)
The conventional approach to developing energetic molecules is to chemically place one or more nitro groups onto a carbon skeleton, which is why the term ''nitration'' is synonymous to explosives preparation. The nitro group carries the oxygen that reacts with the skeletal carbon and hydrogen fuels, which in turn produces the heat and gaseous reaction products necessary for driving an explosive shock. These nitro-containing energetic molecules typically have heats of formation near zero and therefore most of the released energy is derived from the combustion process. Our investigation of the tetrazine, furazan and tetrazole ring systems has offered a different approach to explosives development, where a significant amount of the chemical potential energy is derived from their large positive heats of formation. Because these compounds often contain a large percentage of nitrogen atoms, they are usually regarded as high-nitrogen fuels or explosives. A general artifact of these high-nitrogen compounds is that they are less sensitive to initiation (e.g. by impact) when compared to traditional nitro-containing explosives of similar performances. Using the precursor, 3,6-bis-(3,5-dimethylpyrazol-1-yl)-s-tetrazine, several useful energetic compounds based on the s-tetrazine system have been synthesized and studied. Some of the first compounds are 3,6-diamino-s-tetrazine-1,4-dioxide (LAX-112) and 3,6-dihydrazino-s-tetrazine (DHT). LAX-112 was once extensively studied as an insensitive explosive by Los Alamos; DHT is an example of a high-nitrogen explosive that relies entirely on its heat of formation for sustaining a detonation. Recent synthesis efforts have yielded an azo-s-tetrazine, 3,3'-azobis(6-amino-s-tetrazine) or DAAT, which has a very high positive heat of formation. The compounds, 4,4'-diamino-3,3'-azoxyfurazan (DAAF) and 4,4'-diamino-3,3'-azofurazan (DAAzF), may have important future roles in insensitive explosive
Generation of Single, Monodisperse Compound Droplets
Black, James
The generation of single, monodisperse compound droplets is shown in these fluid dynamics videos. In an apparatus designed to produce single compound droplets, a piezoelectric diaphragm generates a pressure pulse from a voltage waveform input to eject a droplet. In the method presented, oil is allowed to flow into the water nozzle with the pressure pulse ejecting both fluids as a compound droplet. Experiments were performed to demonstrate how changes in water pressure affect compound droplet compositions. It was found that increasing the water pressure decreased the thickness of the compound droplet's oil layer.
English Compounds and Russian Relational Adjectives
Mezhevich, Ilana
English noun-noun compounds are often translated into Russian as relational adjective-noun constructions with the adjective parallel in function to the non-head noun of a compound. However, a large subclass of English compounds which are sometimes referred to as 'deverbal' do not have a relational adjective-noun equivalent in Russian. In deverbal compounds (e.g. van driver), as opposed to so-called 'root' compounds (e.g. bookstore), the head noun is derived from a verb and the non-head nou...
Diffusion mechanisms in intermetallic compounds
Energy Technology Data Exchange (ETDEWEB)
Larikov, L.N. (ANU, Inst. Metallofiziki, Kiev (Ukraine))
Recent research aimed at the identification of the principal mechanisms of diffusion in intermetallics is reviewed. In particular, attention is given to the effect of the type of interatomic bond on the contribution of different mechanisms to diffusion in ordered metallic compounds. Results of an analysis of experimental determinations of diffusion coefficients D(A) and D(B) in binary intermetallics (CuZn, Cu3Sn, AuCd, AgZn, AgMg, InSb, GaSb, AlSb, Fe3Al, FeAl, FeAl3, Ni3Al, Ni3Nb, FeSn, FeSn2, Ni3Sn2, Ni3Sn4, Co3Sn2, CoSn, CoSn2, and CoGa) are presented, and it is shown that the D(A)/D(B) ratio differs substantially for different diffusion mechanisms. 60 refs.
The formation of new compounds
Directory of Open Access Journals (Sweden)
Gasparoli, A.
Full Text Available The formation of new compounds The study of model systems allows us to reconstruct the complex mosaic of reactions which make up the frying process. In particular such systems, if made up of single oils or their components, verify the transformation of the triglyceride matrix by thermo-oxidizing treatment. Should this then have added specific substrates (protein, starch they reconstruct the oil-substrate interaction and the influence of the same substrate in the transformation. The contribution of the information is equally distributed between the volatile products and the complex products; in fact both contribute to indicate the reactions in play, supporting the previous considerations for investigation at an analytical level. The present work discusses the newly formed products (volatile or nonvolatile, verifying in particular the formation of reaction products with the substrates.
GRAPE, System for Pre-compound and Compound Nuclear Reactions
International Nuclear Information System (INIS)
1 - Description of program or function: The GRAPE code system for the calculation of pre-compound and compound nuclear reactions. The main code in this system is GRYPHON. The statistical exciton model following the master-equation approach has been improved and extended for application as an evaluation tool of double- differential reaction cross sections at incident nucleon energies of 5 to 50 MeV. For this purpose the code system GRAPE has been developed, which combines a number of interesting features such as: unified treatment of pre-equilibrium and equilibrium processes, renormalized exciton state-densities summing up to the back-shifted Fermi-gas formula, a new model for the internal transition rates based upon the nucleon mean free path in nuclear matter, angle-energy distributions based on intra-nuclear scattering in nuclear matter, account of discrete-level excitations, a new model for gamma-ray competition, inclusion of multi-particle emission, and various sorting options with code output in the new ENDF-VI format. An important characteristic of the proposed model is that consistency with equilibrium models has been demanded for the summed exciton-state densities as well as for the particle and gamma-ray emission cross sections. Consistency with the adopted state densities has also been imposed upon the internal transition rates. A survey of the theory is given and structure of the GRYPHON code is described. This report also contains a user' manual for GRYPHON. 2 - Method of solution: The master equations are solved with a fast algorithm, without approximations. 3 - Restrictions on the complexity of the problem: - exciton model without spin-parity conservation; - incoming or outgoing particles: a, p, alpha, 3He, d, t, and gamma-rays; - the code has been tested for incoming neutrons only; - not more than 5 multi-particle emissions; - not more than 100 energy points (variable grid); - no calculation of full gamma-ray cascade; - maximum energy of composite
High-Strength, Superelastic Compounds
Stanford, Malcolm; Noebe, Ronald; Dellacorte, Christopher; Bigelow, Glen; Thomas, Fransua
In a previous disclosure, the use of 60- NiTiNOL, an ordered intermetallic compound composed of 60 weight percent nickel and 40 weight percent titanium, was investigated as a material for advanced aerospace bearings due to its unique combination of physical properties. Lessons learned during the development of applications for this material have led to the discovery that, with the addition of a ternary element, the resulting material can be thermally processed at a lower temperature to attain the same desirable hardness level as the original material. Processing at a lower temperature is beneficial, not only because it reduces processing costs from energy consumption, but because it also significantly reduces the possibility of quench cracking and thermal distortion, which have been problematic with the original material. A family of ternary substitutions has been identified, including Hf and Zr in various atomic percentages with varying concentrations of Ni and Ti. In the present innovation, a ternary intermetallic compound consisting of 57.6 weight percent Ni, 39.2 weight percent Ti, and 3.2 weight percent Hf (54Ni-45Ti-1Hf atomic percent) was prepared by casting. In this material, Hf substitutes for some of the Ti atoms in the material. In an alternate embodiment of the innovation, Zr, which is close in chemical behavior to Hf, is used as the substitutional element. With either substitution, the solvus temperature of the material is reduced, and lower temperatures can be used to obtain the necessary hardness values. The advantages of this innovation include the ability to solution-treat the material at a lower temperature and still achieve the required hardness for bearings (at least 50 Rockwell C) and superelastic behavior with recoverable strains greater than 2%. Most structural alloys will not return to their original shape after being deformed as little as 0.2% (a tenth of that possible with superelastic materials like 60 NiTiNOL). Because lower temperatures
Organic electronic devices using phthalimide compounds
Energy Technology Data Exchange (ETDEWEB)
Hassan, Azad M.; Thompson, Mark E.
Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.
Organic electronic devices using phthalimide compounds
Energy Technology Data Exchange (ETDEWEB)
Hassan, Azad M.; Thompson, Mark E.
Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.
Organic electronic devices using phthalimide compounds
Energy Technology Data Exchange (ETDEWEB)
Hassan, Azad M.; Thompson, Mark E.
Organic electronic devices comprising a phthalimide compound. The phthalimide compounds disclosed herein are electron transporters with large HOMO-LUMO gaps, high triplet energies, large reduction potentials, and/or thermal and chemical stability. As such, these phthalimide compounds are suitable for use in any of various organic electronic devices, such as OLEDs and solar cells. In an OLED, the phthalimide compounds may serve various functions, such as a host in the emissive layer, as a hole blocking material, or as an electron transport material. In a solar cell, the phthalimide compounds may serve various functions, such as an exciton blocking material. Various examples of phthalimide compounds which may be suitable for use in the present invention are disclosed.
Two new compounds from Senecio cannabifolius.
Tao, Yi; Jiang, Wei; Cheng, Yi-Yu; Zhang, Yu-Feng
Chemical investigation of the water extracts from the Senecio cannabifolius Less. led us to find two new compounds (1 and 2), along with 12 known compounds (3-14). The two new compounds were determined as (E, 4R)-4-hydroxy-4,5,5-trimethyl-3-(3-oxobut-1-enyl)cyclohex-2-enone (1) and (E)-4-((1S, 3R, 4R)-1-hydroxy-4,5,5-trimethyl-7-oxabicyclo[4.1.0]heptan-1-yl)but-1-en-3-o-ne (2), respectively. The structures of other compounds were elucidated by extensive analysis of spectral data and in comparison with the literature values. Compounds 1 and 2 were evaluated for inhibitory activity against lipopolysaccharide-induced NO production in RAW 264.7 macrophages, and compound 1 showed potent inhibitory activity with IC(50) value of 30.65 μM. PMID:22873286
Compound cryopump for fusion reactors
Kovari, M; Shephard, T
We reconsider an old idea: a three-stage compound cryopump for use in fusion reactors such as DEMO. The helium "ash" is adsorbed on a 4.5 K charcoal-coated surface, while deuterium and tritium are adsorbed at 15-22 K on a second charcoal-coated surface. The helium is released by raising the first surface to ~30 K. In a separate regeneration step, deuterium and tritium are released at ~110 K. In this way, the helium can be pre-separated from other species. In the simplest design, all three stages are in the same vessel, with a single valve to close the pump off from the tokamak during regeneration. In an alternative design, the three stages are in separate vessels, connected by valves, allowing the stages to regenerate without interfering with each other. The inclusion of the intermediate stage would not affect the overall pumping speed significantly. The downstream exhaust processing system could be scaled down, as much of the deuterium and tritium could be returned directly to the reactor. This could reduce ...
Technetium complexation by macrocyclic compounds
International Nuclear Information System (INIS)
Research in nuclear medicine are directed towards the labelling of biological molecules, however, sup(99m)Tc does not show sufficient affinity for these molecules. The aim of this study was to evaluate the ability of macrocyclic compounds to bind strongly technetium in order to be used as complexation intermediate. The reducing agents used were a stannous complex and sodium dithionite. Cryptates and polyesters are not good complexing agents. They form two complexes: a 2:1 sandwich complex or 3:2 and a 1:1 complex. Cyclams are good complexing agents for technetium their complexations strength was determined by competition with pyrophosphate, gluconate and DTPA. Using the method of ligand exchange, the oxidation state of technetium in the Tc-cyclam complex was IV or V. They are 1:1 cationic complexes, the complex charge is +1. The biodistribution in rats of labelling solutions containing (cyclam 14 ane N4) C12H25 shows a good urinary excretion without intoxication risks
Novel Marine Compounds: Anticancer or Genotoxic?
Arif, Jamal M.; Al-Hazzani, Amal A.; Muhammed Kunhi; Fahad Al-Khodairy
In the past several decades, marine organisms have generously gifted to the pharmaceutical industries numerous naturally bioactive compounds with antiviral, antibacterial, antimalarial, anti-inflammatory, antioxidant, and anticancer potentials. But till date only few anticancer drugs (cytarabine, vidarabine) have been commercially developed from marine compounds while several others are currently in different clinical trials. Majority of these compounds were tested in the tumor xenograft mode...
Determination of volatile compounds of pine honeys
SİLİCİ, Sibel
The volatile compounds of 13 Turkish pine (Pinus brutia Ten.) honey samples were characterized by solid phase microextraction (SPME) analysis, followed by gas chromatography-mass spectrometry (GC-MS) analysis. A total of 42 volatile compounds were identified, but volatile compounds such as nonana1, benzene, 4-hexen-3-ol, alpha-pinene, and 2-heptanone were recognized to be specific floral origin markers of the pine honey. The SPME extraction method was proposed as an alternative way to carry o...
Phenolic Compounds and Uses in Fruit Growing
Sulusoglu, Melekber
Phenolic compounds are a class of chemical compounds in organic chemistry which consist of a hydroxyl group directly bonded to an aromatic hydrocarbon group. Phenolic compounds find in cell wall structures and play a major role in the growth regulation of plant as an internal physiological regulators or chemical messengers. They are used in the fruit growing field. They are related with defending system against pathogens and stress. They increase the success of tissue culture; can be helpful ...
Method for the detection of aquaretic compounds
DEFF Research Database (Denmark)
Disclosed is a method for detecting an aquaretic compound. In one embodiment, the method includes administering to a mammal a candidate compound that modulates a nociceptin receptor. Biological material is isolated from the mammal and expression of aquaporin-2 is measured. Modulation of the...... aquaporin-2 is taken to be indicative of a candidate compound having aquaretic activity. The invention has a wide spectrum of uses including helping to identify new diuretics that spare unwanted loss of sodium and potassium ions....
Antibacterial and Antifungal Compounds from Marine Fungi
Lijian Xu; Wei Meng; Cong Cao; Jian Wang; Wenjun Shan; Qinggui Wang
This paper reviews 116 new compounds with antifungal or antibacterial activities as well as 169 other known antimicrobial compounds, with a specific focus on January 2010 through March 2015. Furthermore, the phylogeny of the fungi producing these antibacterial or antifungal compounds was analyzed. The new methods used to isolate marine fungi that possess antibacterial or antifungal activities as well as the relationship between structure and activity are shown in this review.
Hydrodesulfurization catalysis by Chevrel phase compounds
McCarty, Kevin F.; Schrader, Glenn L.
A process is disclosed for the hydrodesulfurization of sulfur-containing hydrocarbon fuel with reduced ternary molybdenum sulfides, known as Chevrel phase compounds. Chevrel phase compounds of the general composition M.sub.x Mo.sub.6 S.sub.8, with M being Ho, Pb, Sn, Ag, In, Cu, Fe, Ni, or Co, were found to have hydrodesulfurization activities comparable to model unpromoted and cobalt-promoted MoS.sub.2 catalysts. The most active catalysts were the "large" cation compounds (Ho, Pb, Sn), and the least active catalysts were the "small" cation compounds (Cu, Fe, Ni, Co.).
Microbial growth on C1 compounds: proceedings
International Nuclear Information System (INIS)
This book contains individual papers prepared for the 4th International Symposium on Microbial Growth on One Carbon Compounds. Individual reports were abstracted and indexed for EDB. Topics presented were in the areas of the physiology and biochemistry of autotraps, physiology and biochemistry of methylotrophs and methanotrops, physiology and biochemistry of methanogens, genetics of microbes that use C1 compounds, taxonomy and ecology of microbes tht grow on C1 compounds, applied aspects of microbes that grow on C1 compounds, and new directions in C1 metabolism. (DT)
Potent antifouling compounds produced by marine Streptomyces
Xu, Ying
Biofouling causes huge economic loss and a recent global ban on organotin compounds as antifouling agents has increased the need for safe and effective antifouling compounds. Five structurally similar compounds were isolated from the crude extract of a marine Streptomyces strain obtained from deep-sea sediments. Antifouling activities of these five compounds and four other structurally-related compounds isolated from a North Sea Streptomyces strain against major fouling organisms were compared to probe structure-activity relationships of compounds. The functional moiety responsible for antifouling activity lies in the 2-furanone ring and that the lipophilicity of compounds substantially affects their antifouling activities. Based on these findings, a compound with a straight alkyl side-chain was synthesized and proved itself as a very effective non-toxic, anti-larval settlement agent against three major fouling organisms. The strong antifouling activity, relatively low toxicity, and simple structures of these compounds make them promising candidates for new antifouling additives. © 2009 Elsevier Ltd. All rights reserved.
Technetium compounds and their field of application
International Nuclear Information System (INIS)
This chapter reviews the different applications of technetium and technetium compounds in catalysis, corrosion inhibition, superconductivity of technetium alloys, diagnostic techniques, radioisotope generators and radiopharmaceuticals. 649 refs
Antimicrobial Action of Compounds from Marine Seaweed
Directory of Open Access Journals (Sweden)
María José Pérez
Full Text Available Seaweed produces metabolites aiding in the protection against different environmental stresses. These compounds show antiviral, antiprotozoal, antifungal, and antibacterial properties. Macroalgae can be cultured in high volumes and would represent an attractive source of potential compounds useful for unconventional drugs able to control new diseases or multiresistant strains of pathogenic microorganisms. The substances isolated from green, brown and red algae showing potent antimicrobial activity belong to polysaccharides, fatty acids, phlorotannins, pigments, lectins, alkaloids, terpenoids and halogenated compounds. This review presents the major compounds found in macroalga showing antimicrobial activities and their most promising applications.
Antimicrobial Action of Compounds from Marine Seaweed.
Pérez, María José; Falqué, Elena; Domínguez, Herminia
Seaweed produces metabolites aiding in the protection against different environmental stresses. These compounds show antiviral, antiprotozoal, antifungal, and antibacterial properties. Macroalgae can be cultured in high volumes and would represent an attractive source of potential compounds useful for unconventional drugs able to control new diseases or multiresistant strains of pathogenic microorganisms. The substances isolated from green, brown and red algae showing potent antimicrobial activity belong to polysaccharides, fatty acids, phlorotannins, pigments, lectins, alkaloids, terpenoids and halogenated compounds. This review presents the major compounds found in macroalga showing antimicrobial activities and their most promising applications. PMID:27005637
Directory of Open Access Journals (Sweden)
Andreia Corciovă
Full Text Available The objectives of this study were to examine the potential of beta-cyclodextrin to improve the solubility of rutin and obtain inclusion compounds that were analyzed by different techniques: UV-Vis, IR spectroscopy, thermal analysis. The presence of β-cyclodextrin raises the content of rutin in water. The inclusion compounds were prepared by dry mixing, complexation in semisolid and liquid medium in 1:2 molar ratio rutin - β-cyclodextrin. The UV-Vis and IR analysis demonstrated the obtaining of inclusion compounds and the thermal analysis show that these compounds are more stable than the parent substance.
A Probabilistic Model of Compound Nouns
Lauer, M; Lauer, Mark; Dras, Mark
Compound nouns such as example noun compound are becoming more common in natural language and pose a number of difficult problems for NLP systems, notably increasing the complexity of parsing. In this paper we develop a probabilistic model for syntactically analysing such compounds. The model predicts compound noun structures based on knowledge of affinities between nouns, which can be acquired from a corpus. Problems inherent in this corpus-based approach are addressed: data sparseness is overcome by the use of semantically motivated word classes and sense ambiguity is explicitly handled in the model. An implementation based on this model is described in Lauer (1994) and correctly parses 77% of the test set.
Automated compound classification using a chemical ontology
Directory of Open Access Journals (Sweden)
Bobach Claudia
Full Text Available Abstract Background Classification of chemical compounds into compound classes by using structure derived descriptors is a well-established method to aid the evaluation and abstraction of compound properties in chemical compound databases. MeSH and recently ChEBI are examples of chemical ontologies that provide a hierarchical classification of compounds into general compound classes of biological interest based on their structural as well as property or use features. In these ontologies, compounds have been assigned manually to their respective classes. However, with the ever increasing possibilities to extract new compounds from text documents using name-to-structure tools and considering the large number of compounds deposited in databases, automated and comprehensive chemical classification methods are needed to avoid the error prone and time consuming manual classification of compounds. Results In the present work we implement principles and methods to construct a chemical ontology of classes that shall support the automated, high-quality compound classification in chemical databases or text documents. While SMARTS expressions have already been used to define chemical structure class concepts, in the present work we have extended the expressive power of such class definitions by expanding their structure-based reasoning logic. Thus, to achieve the required precision and granularity of chemical class definitions, sets of SMARTS class definitions are connected by OR and NOT logical operators. In addition, AND logic has been implemented to allow the concomitant use of flexible atom lists and stereochemistry definitions. The resulting chemical ontology is a multi-hierarchical taxonomy of concept nodes connected by directed, transitive relationships. Conclusions A proposal for a rule based definition of chemical classes has been made that allows to define chemical compound classes more precisely than before. The proposed structure-based reasoning
A Method for Synthetic Aperture Compounding
DEFF Research Database (Denmark)
Hansen, Jens Munk; Jensen, Jørgen Arendt
An approach to perform ultrasound spatial compounding using synthetic aperture data is proposed. The approach allows compounding to be performed for any number of directions without reducing the frame rate or temporal resolution. It is demonstrated how the contrast is improved by compounding and...... obtained when using 5 images. Using the same RF data, a synthetic aperture image without compounding reveals a CNR of -0.36, -0.93, -1.23, and -1.61 dB for the four cysts, respectively....
Investigations on organogermanium compounds XII. Reactions of trialkylgermylalkalimetal compounds in hexamethylphosphoric triamide (HMPT) with some inorganic and organic compounds
Bulten, E.J.; Noltes, J.G.
Trialkylgermyl alkali metal compounds in HMPT have been found to be highly reactive nucleophiles. Reactions with some inorganic and organic compounds, such as oxygen, carbon dioxide, inorganic and orgaanic halides, aldehydes, ketones, epoxides and lactones are described. Several new carbon-functiona
DEFF Research Database (Denmark)
Andersen, Jan Rud; Engler, E. M.; Green, D. C.; Patel, V. V.
There is described the preparation of bis-1,3-dithiole compounds (I) which are key synthetic precursors for the preparation of new polymeric metal bis(dithiolene) (i.e., II) and tetrathiafulvalene compounds (i.e., III): (Image Omitted)...
Intercalation Compounds of Barium and Strontium Phenylphosphonate
Czech Academy of Sciences Publication Activity Database
Beneš, L.; Melánová, Klára; Svoboda, Jan; Zima, Vítězslav; Růžička, A.
Pardubice : Institute of Macromolecular Chemistry AS CR, 2011. s. 172. ISBN 978-80-85009-66-8. [16th International Symposium on Intercalation Compounds. 23.05.2011-26.05.2011, Seč] Institutional research plan: CEZ:AV0Z40500505 Keywords : intercalates * layered compounds * structure Subject RIV: CA - Inorganic Chemistry
Organic halogen compounds in the environment
International Nuclear Information System (INIS)
There are 20 research reports on selected problems concerning the analysis, the occurence, and the behaviour of a wide spectrum of organic halogen compounds. The work was carried out in the framework of the project 'Organic Halogen Compounds in the Environment', financed by the BMFT, between 1975 and 1978. (orig.)
Performance of BNL-TSTA compound cryopump
International Nuclear Information System (INIS)
A compound cryopump using cryocondensation pumping for hydrogen isotopes and cryosorption pumping with coconut charcoal as adsorbent for helium was designed. This compound cryopump was subsequently built (by Janis Research, Stoneham, MA) and has been tested at Brookhaven, fulfilling the design requirements and are delivered to Tritium Systems Test Assembly (TSTA) Vacuum Facility at Los Alamos Scientific Laboratory (LASL) for on-line operations
Improvements in or relating to compounds
International Nuclear Information System (INIS)
The invention provides a process for the preparation of a dispersible product containing a cerium compound which comprises heating a cerium (IV) oxide hydrate in the presence of a salt to cause deaggregation of aggregated crystallites in the cerium (IV) oxide hydrate and produce a dispersible product containing a cerium compound. (author)
Lattice anisotropy in uranium ternary compounds
DEFF Research Database (Denmark)
Maskova, S.; Adamska, A.M.; Havela, L.;
Several U-based intermetallic compounds (UCoGe, UNiGe with the TiNiSi structure type and UNiAl with the ZrNiAl structure type) and their hydrides were studied from the point of view of compressibility and thermal expansion. Confronted with existing data for the compounds with the ZrNiAl structure...
Volatile organic compound emissions from silage systems
As a precursor to smog, emission of volatile organic compounds (VOCs) to the atmosphere is an environmental concern in some regions. The major source from farms is silage, with emissions coming from the silo face, mixing wagon, and feed bunk. The major compounds emitted are alcohols with other impor...
Use of Polyphenolic Compounds in Dermatologic Oncology.
Costa, Adilson; Bonner, Michael Yi; Arbiser, Jack L
Polyphenols are a widely used class of compounds in dermatology. While phenol itself, the most basic member of the phenol family, is chemically synthesized, most polyphenolic compounds are found in plants and form part of their defense mechanism against decomposition. Polyphenolic compounds, which include phenolic acids, flavonoids, stilbenes, and lignans, play an integral role in preventing the attack on plants by bacteria and fungi, as well as serving as cross-links in plant polymers. There is also mounting evidence that polyphenolic compounds play an important role in human health as well. One of the most important benefits, which puts them in the spotlight of current studies, is their antitumor profile. Some of these polyphenolic compounds have already presented promising results in either in vitro or in vivo studies for non-melanoma skin cancer and melanoma. These compounds act on several biomolecular pathways including cell division cycle arrest, autophagy, and apoptosis. Indeed, such natural compounds may be of potential for both preventive and therapeutic fields of cancer. This review evaluates the existing scientific literature in order to provide support for new research opportunities using polyphenolic compounds in oncodermatology. PMID:27164914
Compound for consolidating particulate materials. [French patent
Energy Technology Data Exchange (ETDEWEB)
Van Blaricom, L.E.; Deweyert, H.R.; Smith, N.H.
This compound consists of a sulfonated polyphenolic material extracted from the bark of coniferous trees and/or quebracho wood, a water-soluble bichromate, and borax. The aqueous compound with a pH of 8 to 10.5 is mixed with solid particulate materials, such as earth, sand or gravel.
Chalcones: compounds possessing a diversity in applications
Urmila Berar
Chalcones are a class of α, β- unsaturated carbonyl compounds that form the central core for a variety of naturally occurring biologically active compounds. They exhibit tremendous potential to act as a pharmacological agent. Besides their various pharmacological activities, chalcones have been explored for different optical applications including second harmonic generation materials in non- linear optics, fluorescent probe for sensing different molecules.
Magnetic properties of rare earth iron compounds
International Nuclear Information System (INIS)
In this thesis, a study is made of hyperfine interactions in the intermetallic compounds Rsub(x)Fesub(y) (R = rare earth, Y or Th) by using the Moessbauer effect in the 57Fe nucleus. The hyperfine interactions in two series of Rsub(x)Fesub(y) compounds, for which Ysub(x)Fesub(y) and Ersub(x)Fesub(y) were chosen, are studied. Thus a comparison can be made between the magnetic properties of compounds with diamagnetic yttrium and ferromagnetic erbium, respectively. In addition, the magnetic anisotropy of these compounds Ysub(x)Fesub(y) and Ersub(x)Fesub(y) has been investigated. The major part of this thesis concerns a study of the R2Fe17 intermetallic compounds. Since Co or Ni substitution for Fe in R2Fe17 compounds results in a fast increase of the Curie temperature, some pseudobinary R2Fesub(17-x)Msub(x) compounds with R = Tm and Er and M = Co and Ni, have been investigated. ThFe5 has been studied, since it is the only known existing RFe5 compound with a crystal structure which is closely related to that of Th2Fe17
Hybrid Compounding in New Zealand English
Degani, Marta; Onysko, Alexander
This study investigates hybrid compound formation of Maori and English terms in present day New Zealand English (NZE). On the background of Maori and English language contact, the phenomenon of hybrid compounding emerges as a process that, on the one hand, symbolizes the vitality of the Maori element in NZE and, on the other hand, marks the…
Intercalated compounds of niobium and tantalum dicalcogenides
International Nuclear Information System (INIS)
The synthesis of niobium and tantalum lamellar compounds and its intercalated derivatives is described. The intercalated compounds with lithium, with alkaline metal and with metals of the first-row transition are studied, characterized by X-ray diffraction. (C.G.C.)
Methods of making organic compounds by metathesis
Energy Technology Data Exchange (ETDEWEB)
Abraham, Timothy W.; Kaido, Hiroki; Lee, Choon Woo; Pederson, Richard L.; Schrodi, Yann; Tupy, Michael John
Described are methods of making organic compounds by metathesis chemistry. The methods of the invention are particularly useful for making industrially-important organic compounds beginning with starting compositions derived from renewable feedstocks, such as natural oils. The methods make use of a cross-metathesis step with an olefin compound to produce functionalized alkene intermediates having a pre-determined double bond position. Once isolated, the functionalized alkene intermediate can be self-metathesized or cross-metathesized (e.g., with a second functionalized alkene) to produce the desired organic compound or a precursor thereto. The method may be used to make bifunctional organic compounds, such as diacids, diesters, dicarboxylate salts, acid/esters, acid/amines, acid/alcohols, acid/aldehydes, acid/ketones, acid/halides, acid/nitriles, ester/amines, ester/alcohols, ester/aldehydes, ester/ketones, ester/halides, ester/nitriles, and the like.
Microbial metabolism of organosulfur compounds in petroleum
International Nuclear Information System (INIS)
The microbial metabolism of a large number of hydrocarbons has been thoroughly studied and described in the literature. In contrast, much less is known about the metabolism of organosulfur compounds found in petroleum. These investigations have been hampered by the commercial unavailability of most of the sulfur compounds of interest. Some of the first studies on the biodegradation of sulfur compounds focused on their fate and removal from oil-contaminated environments. Another major area of study is the microbial process of 'biodesulfurization' which has been suggested as a means of selectively removing sulfur compounds from petroleum prior to refining. Information gathered from these two areas of research provide the basis of the present knowledge of metabolism of organosulfur compounds in petroleum. This information is reviewed with emphasis on the metabolism of dibenzothiophenes and n-alkyl tetrahydrothiophenes (n-alkyl thiolanes)
Characteristic Aroma Compounds from Different Pineapple Parts
Directory of Open Access Journals (Sweden)
Guang-Ming Sun
Full Text Available Characteristic aroma volatile compounds from different parts of cayenne pineapple were analyzed by headspace-solid phase microextraction (HS-SPME and gas chromatography-mass spectrometry (GC/MS. The main volatile compounds were esters, terpenes, ketones and aldehydes. The number and content of aroma compounds detected in pulp were higher than those found in core. In pulp, the characteristic aroma compounds were ethyl 2-methylbutanoate, ethyl hexanoate, 2,5-dimethyl-4-hydroxy-3(2H-furanone (DMHF, decanal, ethyl 3-(methylthiopropionate, ethyl butanoate, and ethyl (E-3-hexenoate; while in core the main compounds were ethyl 2-methylbutanoate, ethyl hexanoate and DMHF. The highest odor units were found to correspond to ethyl 2-methylbutanoate, followed by ethyl hexanoate and DMHF. The odor units found for pulp were higher than those for core.
Integrated modelling of two xenobiotic organic compounds
DEFF Research Database (Denmark)
Lindblom, Erik Ulfson; Gernaey, K.V.; Henze, Mogens;
This paper presents a dynamic mathematical model that describes the fate and transport of two selected xenobiotic organic compounds (XOCs) in a simplified representation. of an integrated urban wastewater system. A simulation study, where the xenobiotics bisphenol A and pyrene are used as reference...... compounds, is carried out. Sorption and specific biological degradation processes are integrated with standardised water process models to model the fate of both compounds. Simulated mass flows of the two compounds during one dry weather day and one wet weather day are compared for realistic influent flow...... rate and concentration profiles. The wet weather day induces resuspension of stored sediments, which increases the pollutant load on the downstream system. The potential of the model to elucidate important phenomena related to origin and fate of the model compounds is demonstrated....
New uranium compounds preparation and use as catalyst for hydrogenation of non-saturated organic compounds
International Nuclear Information System (INIS)
Preparation of new organic uranium compounds and their use as catalysts for hydrogenation of non-saturated organic compounds are described. These compounds include Uranium III, a cyclopentadienic group, an alkyl group and an acetylenic derivative C6H5C triple bonds CR fixed by a π bond. Catalysts can be prepared with depleted uanium for hydrogenation of olefins for example
Thiophenic Sulfur Compounds Released During Coal Pyrolysis.
Xing, Mengwen; Kong, Jiao; Dong, Jie; Jiao, Haili; Li, Fan
Thiophenic sulfur compounds are released during coal gasification, carbonization, and combustion. Previous studies indicate that thiophenic sulfur compounds degrade very slowly in the environment, and are more carcinogenic than polycyclic aromatic hydrocarbons and nitrogenous compounds. Therefore, it is very important to study the principle of thiophenic sulfur compounds during coal conversion, in order to control their emission and promote clean coal utilization. To realize this goal and understand the formation mechanism of thiophenic sulfur compounds, this study focused on the release behavior of thiophenic sulfur compounds during coal pyrolysis, which is an important phase for all coal thermal conversion processes. The pyrolyzer (CDS-5250) and gas chromatography-mass spectrometry (Focus GC-DSQII) were used to analyze thiophenic sulfur compounds in situ. Several coals with different coal ranks and sulfur contents were chosen as experimental samples, and thiophenic sulfur compounds of the gas produced during pyrolysis under different temperatures and heating rates were investigated. Levels of benzothiophene and dibenzothiophene were obtained during pyrolysis at temperatures ranging from 200°C to 1300°C, and heating rates ranging from 6°C/ms to 14°C/ms and 6°C/s to 14°C/s. Moreover, the relationship between the total amount of benzothiophene and dibenzothiophene released during coal pyrolysis and the organic sulfur content in coal was also discussed. This study is beneficial for understanding the formation and control of thiophenic sulfur compounds, since it provides a series of significant results that show the impact that operation conditions and organic sulfur content in coal have on the amount and species of thiophenic sulfur compounds produced during coal pyrolysis. PMID:23781126
Cytotoxic Compounds Isolated from Murraya tetramera Huang
Directory of Open Access Journals (Sweden)
Chun-Xue You
Full Text Available A new compound and seven known compounds were isolated from Murraya tetramera Huang for the first time, and they were identified with NMR and MS spectral analysis. It was confirmed that the new compound was 10-methoxy-7-methyl-2H-benzo[g]chromen-2-one (3 and the others were β-eudesmol (1, trans-3β-(1-hydroxy-1-methylethyl-8aβ-methyl-5-methylenedecalin-2-one (2, 5,7-dimethoxy-8-[(Z-3'-methyl-butan-1',3'-dienyl]coumarin (4, 7-geranyloxy-6-methoxycoumarin (5, 5,7-dimethoxy-8-(3-methyl-2-oxo-butylcoumarin (6, murrangatin acetate (7 and toddalenone (8. Furthermore, the cytotoxic activity against human lung adenocarcinoma (A549, human hepatocellular carcinoma cells (SMMC-7721, human bladder tumor cells (EJ, human cervical carcinoma cells (HeLa, and human B-lineage acute lymphoblastic leukemia 1 cells (BALL-1 was evaluated for all compounds. It was found that five of them displayed various degrees of cytotoxicity against different testing targets. Compound 1 showed significant cytotoxic activity against the five cell lines (A549, SMMC-7721, EJ, Hela and BALL-1. Compounds 2 and 5 showed significant cytotoxicity against three cell lines (A549, SMMC-7721 and BALL-1. Compound 4 showed significant cytotoxicity against three cell lines (A549, EJ and BALL-1. However, compound 3 only showed fair cytotoxicity against the BALL-1 cell line. The structure-active relationships were investigated as well. These active compounds might be potential lead compounds for the treatment of cancer.
Biodegradable compounds: Rheological, mechanical and thermal properties
Nobile, Maria Rossella; Lucia, G.; Santella, M.; Malinconico, M.; Cerruti, P.; Pantani, R.
Recently great attention from industry has been focused on biodegradable polyesters derived from renewable resources. In particular, PLA has attracted great interest due to its high strength and high modulus and a good biocompatibility, however its brittleness and low heat distortion temperature (HDT) restrict its wide application. On the other hand, Poly(butylene succinate) (PBS) is a biodegradable polymer with a low tensile modulus but characterized by a high flexibility, excellent impact strength, good thermal and chemical resistance. In this work the two aliphatic biodegradable polyesters PBS and PLA were selected with the aim to obtain a biodegradable material for the industry of plastic cups and plates. PBS was also blended with a thermoplastic starch. Talc was also added to the compounds because of its low cost and its effectiveness in increasing the modulus and the HDT of polymers. The compounds were obtained by melt compounding in a single screw extruder and the rheological, mechanical and thermal properties were investigated. The properties of the two compounds were compared and it was found that the values of the tensile modulus and elongation at break measured for the PBS/PLA/Talc compound make it interesting for the production of disposable plates and cups. In terms of thermal resistance the compounds have HDTs high enough to contain hot food or beverages. The PLA/PBS/Talc compound can be, then, considered as biodegradable substitute for polystyrene for the production of disposable plates and cups for hot food and beverages.
Phenolic compounds in Ross Sea water
Zangrando, Roberta; Barbaro, Elena; Gambaro, Andrea; Barbante, Carlo; Corami, Fabiana; Kehrwald, Natalie; Capodaglio, Gabriele
Phenolic compounds are semi-volatile organic compounds produced during biomass burning and lignin degradation in water. In atmospheric and paleoclimatic ice cores studies, these compounds are used as biomarkers of wood combustion and supply information on the type of combusted biomass. Phenolic compounds are therefore indicators of paleoclimatic interest. Recent studies of Antarctic aerosols highlighted that phenolic compounds in Antarctica are not exclusively attributable to biomass burning but also derive from marine sources. In order to study the marine contribution to aerosols we developed an analytical method to determine the concentration of vanillic acid, vanillin, p-coumaric acid, syringic acid, isovanillic acid, homovanillic acid, syringaldehyde, acetosyringone and acetovanillone present in dissolved and particle phases in Sea Ross waters using HPLC-MS/MS. The analytical method was validated and used to quantify phenolic compounds in 28 sea water samples collected during a 2012 Ross Sea R/V cruise. The observed compounds were vanillic acid, vanillin, acetovanillone and p-coumaric acid with concentrations in the ng/L range. Higher concentrations of analytes were present in the dissolved phase than in the particle phase. Sample concentrations were greatest in the coastal, surficial and less saline Ross Sea waters near Victoria Land.
Risk and liabilities of prescribing compounded medications.
Randell, Michael D; Duffy, Phillip J
Complications resulting from the use of compounded medications have become a troubling trend nationwide. There is a significant potential for patients to suffer serious harm from the use of substandard medications prepared by compounding pharmacies, and the reality of this problem has been demonstrated in several well-publicized incidences of serious medical complications, including patient deaths, that directly resulted from the use of medications prepared at compounding pharmacies. Unlike US Food and Drug Administration (FDA)-approved drugs, compounded products are not required to meet evidentiary standards for establishing safety and efficacy. Moreover, these products are not held to Good Manufacturing Practices, which require regular inspections, quality control testing, and rejection of material not meeting specifications. Physicians, as well as other prescribers, need to be aware that when a patient suffers harm from using a compounded medication, those injured patients may bring negligence and malpractice claims, not only against the pharmacy and the pharmacist responsible for preparing the medication, but also against the prescribing physician and the physician's practice. Consequently, the best way for physicians to manage professional risk and avoid both litigation and potential negative patient outcomes related to compounded pharmaceuticals is to not use these products if there is an FDA-approved product available. However, if the use of a compounded medication is medically necessary, then physicians should adhere to the FDA guidance concerning traditional compounding. Moreover, it would be prudent for any physician who intends to either resell or participate in the distribution of compounded products beyond the direct treatment of their patients to consider obtaining the appropriate insurance coverage for this activity. PMID:25276868
Bioremediation of nitroaromatic and haloaromatic compounds
Energy Technology Data Exchange (ETDEWEB)
Alleman, B.C.; Leeson, A.
Sites contaminated with explosive compounds, pesticides, herbicides, PCBs, and other aromatic compounds present formidable technical, regulatory, and financial challenges. The application of bioremediatin technologies at such sites offers the promise of cost-effective site remediation that can serve as a key component of a well-formulated strategy for achieving site closure. This volume presents the results of bench-, pilot-, and field-scale projects focused on the use of biological approaches to remediate problem compounds, such as RDX, HMX, TNT, DDT, 2,4-D, nitro- and chlorobenzenes, nitroaniline, chloroaniline, hexachlorbenzene, PCPs, PCBs, and dichlorophenol in soils and groundwater.
Bioremediation of nitroaromatic and haloaromatic compounds
Energy Technology Data Exchange (ETDEWEB)
Alleman, B.C.; Leeson, A.
Sites contaminated with explosive compounds, pesticides, herbicides, PCBs, and other aromatic compounds present formidable technical, regulatory, and financial challenges. The application of bioremediatin technologies at such sites offers the promise of cost-effective site remediation that can serve as a key component of a well-formulated strategy for achieving site closure. This volume presents the results of bench-, pilot-, and field-scale projects focused on the use of biological approaches to remediate problem compounds, such as RDX, HMX, TNT, DDT, 2,4-D, nitro- and chlorobenzenes, nitroaniline, chloroaniline, hexachlorbenzene, PCPs, PCBs, and dichlorophenol in soils and groundwater.
Bioremediation of nitroaromatic and haloaromatic compounds
Energy Technology Data Exchange (ETDEWEB)
Alleman, B.C.; Leeson, A. [eds.
Sites contaminated with explosive compounds, pesticides, herbicides, PCBs, and other aromatic compounds present formidable technical, regulatory, and financial challenges. The application of bioremediation technologies at such sites offers the promise of cost-effective site remediation that can serve as a key component of a well-formulated strategy for achieving site closure. This volume presents the results of bench-, pilot-, and field-scale projects focused on the use of biological approaches to remediate problem compounds, such as RDX, HMX, TNT, DDT, 2,4-D, nitro- and chlorobenzenes, nitroaniline, chloroaniline, hexachlorobenzene, PCPs, PCBs, and dichlorophenol in soils and groundwater.
Institute of Scientific and Technical Information of China (English)
Experimental researches were conducted on flood carrying capacity of compound open channels with wide and narrow floodplains as well as hydrodynamic behavior of overbank flow across vegetated floodplains. Results show that hydrodynamic behavior of compound channels with narrow floodplains is different from that of the wide floodplains. In such compound channels with narrow vegetated floodplains as in the Pearl River delta nework, it has been found that vegetated domains become really impenetrable when the length of vegetated domain is larger than Lm, the length of flow in floodplain coming into the main channel, and that the influence of vegetated floodplains upon flood stages of a channel is not very significant.
Three new compounds from Cinnamomum cassia.
He, Shan; Jiang, Yong; Tu, Peng-Fei
Three new compounds, including two new diterpenoids, named epianhydrocinnzeylanol (1) and cinnacasiol H (2), and one hydroxylasiodiplodin, (3R,4S,6R)-4,6-dihydroxy-de-O-methyllasiodiplodin (3), together with five known diterpenoids (4-8) and two known phenolic glycosides (9-10) were isolated from the barks of Cinnamomum cassia. Their structures were elucidated by extensive spectroscopic analysis and comparison of the chemical shift values with those of related known compounds. The anti-inflammatory activities of the isolates were evaluated on nitric oxide production in lipopolysaccharide-induced BV-2 microglial cells and the compounds showed weak inhibition activities. PMID:26498626
Capacity results for compound wiretap channels
Sommerfeld, Jochen; Boche, Holger
We derive a lower bound on the secrecy capacity of the compound wiretap channel with channel state information at the transmitter which matches the general upper bound on the secrecy capacity of general compound wiretap channels given by Liang et al. and thus establishing a full coding theorem in this case. We achieve this with a stronger secrecy criterion and with a decoder that is robust against the effect of randomisation in the encoding. This relieves us from the need of decoding the randomisation parameter which is in general not possible within this model. Moreover we prove a lower bound on the secrecy capacity of the compound wiretap channel without channel state information.
Pickpocket compounds from Latin to Romance
DEFF Research Database (Denmark)
Whitehead, Benedicte Nielsen
This thesis discusses the development in Proto–Indo–European, Latin and Romance of a word–formation pattern which the most adequate terminology in use dubs 'verbal government compounds with a governing first member'; I use the shorthand 'pickpocket compounds'. The first member of such compounds......–noun, represented by truck–driver, has the deverbal member second and carries an agentive suffix, -er. Pickpocket compounds are attested in early strata of Greek and Indo–Iranian and in medieval strata of Germanic, Slavic and Romance. Latin has around a dozen examples. The scholarly debate, continued in this thesis...
Health promoting compounds in vegetables and fruits:
DEFF Research Database (Denmark)
Brandt, K.; Christensen, L.P.; Hansen-Møller, J.;
Vegetables contain unknown compounds with important health promoting effect. The described project defined and tested a two-step screening procedure for identification of such compounds. Step 1 is initial screening according to three criteria: 1.1, chemically reactive functional groups; 1.......2, toxicity at high concentrations or other bioactivity; and 1.3, presence in healthy foods. Step 2 is testing for minimum criteria defining health-promoting compounds: 2.1, positive or biphasic ("hormesis") responses in bioassay; 2.2, human tissue concentrations corresponding to beneficial effects in...
Chlorinated organic compounds produced by Fusarium graminearum.
Ntushelo, Khayalethu
Fusarium graminearum, a pathogen of wheat and maize, not only reduces grain yield and degrades quality but also produces mycotoxins in the infected grain. Focus has been on mycotoxins because of the human and animal health hazards associated with them. In addition to work done on mycotoxins, chemical profiling of F. graminearum to identify other compounds produced by this fungus remains critical. With chemical profiling of F. graminearum the entire chemistry of this fungus can be understood. The focus of this work was to identify chlorinated compounds produced by F. graminearum. Various chlorinated compounds were detected and their role in F. graminearum is yet to be understood. PMID:27165533
Synthesis of Novel Antifungal Triazole Compounds
Institute of Scientific and Technical Information of China (English)
Yong CHU; Ming Xia XU; Ding LU
Based on our previous studies of 3D-QSAR, 38 novel objective compounds belonging to 4 series were designed and successfully synthesized directed by the idea of reconstructing the structure of non-pharmacophores while reserving essential ones in triazoles. In vitro pilot studies on their antifungal activities showed that most compounds have inhibitory effects on C.albicans and some inhibit S.cerevisiae also. The effects on C.albicans of 5 compounds are more potent than or equal to that of fluconazole or itraconazole.
Allylic Nitro Compounds as Nitrite Donors
Chakrapani, Harinath; Gorczynski, Michael J.; King, S Bruce
Allylic nitro compounds were synthesized and evaluated as organic sources of nitrite and nitric oxide. Unactivated allylic nitro compounds do not spontaneously release nitrite and nucleophile promoted nitrite release is slow. However, 2-(nitromethyl)-cyclohex-1-ene-3-one spontaneously dissociates in buffer (pH = 7.4) to release nitrite with a kobs = 1.6 × 10−5 s−1. In the presence of L-cysteine, this compound rapidly yields nitrite and reacts with hemoglobin similarly to sodium nitrite. Struc...
Expatriate Compound Living: An Ethnographic Field Study
DEFF Research Database (Denmark)
Lauring, Jakob; Selmer, Jan
In certain countries, closed expatriate compounds have developed. They serve to provide resident expatriates and accompanying family members with a comfortable and safe environment. Unfortunately, not much is known about compound life since associated empirical research is scarce. Through...... ethnographic field-work methodology, including interviews and participant observation during a period of three months, this exploratory study investigated 16 Danish business expatriates of a large Danish corporation and their families living in the same compound in Saudi Arabia. They shared their spare time...
Cytotoxic Compounds Isolated from Murraya tetramera Huang
Chun-Xue You; Kai Yang; Cheng-Fang Wang; Wen-Juan Zhang; Ying Wang; Jiao Han; Li Fan; Shu-Shan Du; Zhu-Feng Geng; Zhi-Wei Deng
A new compound and seven known compounds were isolated from Murraya tetramera Huang for the first time, and they were identified with NMR and MS spectral analysis. It was confirmed that the new compound was 10-methoxy-7-methyl-2H-benzo[g]chromen-2-one (3) and the others were β-eudesmol (1), trans-3β-(1-hydroxy-1-methylethyl)-8aβ-methyl-5-methylenedecalin-2-one (2), 5,7-dimethoxy-8-[(Z)-3'-methyl-butan-1',3'-dienyl]coumarin (4), 7-geranyloxy-6-methoxycoumarin (5), 5,7-dimethoxy-8-(3-methyl-2-o...
Endocannabinoids, Related Compounds and Their Metabolic Routes
Directory of Open Access Journals (Sweden)
Filomena Fezza
Full Text Available Endocannabinoids are lipid mediators able to bind to and activate cannabinoid receptors, the primary molecular targets responsible for the pharmacological effects of the Δ9-tetrahydrocannabinol. These bioactive lipids belong mainly to two classes of compounds: N-acylethanolamines and acylesters, being N-arachidonoylethanolamine (AEA and 2-arachidonoylglycerol (2-AG, respectively, their main representatives. During the last twenty years, an ever growing number of fatty acid derivatives (endocannabinoids and endocannabinoid-like compounds have been discovered and their activities biological is the subject of intense investigations. Here, the most recent advances, from a therapeutic point of view, on endocannabinoids, related compounds, and their metabolic routes will be reviewed.
Novel Marine Compounds: Anticancer or Genotoxic?
Directory of Open Access Journals (Sweden)
Arif Jamal M.
Full Text Available In the past several decades, marine organisms have generously gifted to the pharmaceutical industries numerous naturally bioactive compounds with antiviral, antibacterial, antimalarial, anti-inflammatory, antioxidant, and anticancer potentials. But till date only few anticancer drugs (cytarabine, vidarabine have been commercially developed from marine compounds while several others are currently in different clinical trials. Majority of these compounds were tested in the tumor xenograft models, however, lack of anticancer potential data in the chemical- and/or oncogene-induced pre-initiation animal carcinogenesis models might have cost some of the marine anticancer compounds an early exit from the clinical trials. This review critically discusses importance of preclinical evaluation, failure of human clinical trials with certain potential anticancer agents, the screening tests used, and choice of biomarkers.
Chemistry of tin compounds and environment
International Nuclear Information System (INIS)
Of the large volume of tin compounds reported in the literature, possible only 100 are commercially important. Tin compounds are a wide variety of purposes such as catalysts, stabilizers for many materials including polymer, biocidal agents, bactericides, insecticides, fungicides, wood preservatives, acaricides and anti fouling agents in paints, anticancer and antitumour agents, ceramic opacifiers, as textile additives, in metal finishing operations, as food additives and in electro conductive coating. All these applications make the environment much exposed to tin contamination. The application of organotin compounds as biocides account for about 30% of total tin consumption suggesting that the main environmental effects are likely to originate from this sector. Diorgano tins and mono-organo tins are used mainly in plastic industry which is the next big source for environmental pollution. In this presentation all environmental aspects of the use of tin compounds and the recommended preventive measures are discussed. (author)
Trifluoromethylation of Carbonyl Compounds with Sodium Trifluoroacetate
Institute of Scientific and Technical Information of China (English)
In the presence of copper (Ⅰ) halide as catalyst, a variety of carbonyl compounds could be trifluoromethylated with sodium trifluoroacetate to give the corresponding alcohols in moderate to high yields.
Mechanochemical reactions on copper-based compounds
H.L. Castricum; H. Bakker; E.K. Poels
Mechanochemical reactions of copper and copper oxides with oxygen and carbon dioxide are discussed, as well as decomposition and reduction of copper compounds by mechanical milling under high-vacuum conditions.
Phytoestrogens: Plant-derived Estrogenic Compounds
Directory of Open Access Journals (Sweden)
Nevzat Konar
Full Text Available Estrogen is a hormone, which is produced in ovary and testis; however, it has many biological effects besides the reproductive system. Phytoestrogens are the compounds, which have estrogen-like structure and activities, taking place in structure of various edible plants at different levels and in different compositions. These compounds attracted notice after the first quarter of 20th century upon they had been associated with infertility seen in some of animals fed with alfalfa, and these compounds have been identified in human-derived biological samples and its effects on health have been taken under study in the recent 30 years. These materials have especially antioxidant role in plants while they have activities in animals and humans as estrogen agonist and antagonists. Based on their chemical structure, they may be gathered under especially isoflavon and lignan groups while some of members of coumestan and stilbene groups are also identified as phytoestrogenic compound.
Negative thermal expansion in framework compounds
Indian Academy of Sciences (India)
R Mittal
We have studied negative thermal expansion (NTE) compounds with chemi- cal compositions of NX2O8 and NX2O7 (N=Zr, Hf and X=W, Mo, V) and M2O (M=Cu, Ag) using the techniques of inelastic neutron scattering and lattice dynamics. There is a large variation in the negative thermal expansion coefficients of these compounds. The inelastic neutron scattering experiments have been carried out using polycrystalline and single crystal samples at ambient pressure as well as at high pressures. Experimental data are useful to confirm the predictions made from our lattice dynamical calculations as well as to check the quality of the interatomic potentials developed by us. We have been able to successfully model the NTE behaviour of these compounds. Our studies show that unusual phonon softening of low energy modes is able to account for NTE in these compounds.
Techniques for Analysis of Plant Phenolic Compounds
Directory of Open Access Journals (Sweden)
Thomas H. Roberts
Full Text Available Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules have occurred over the last 25 years. Organic solvent extraction is the main method used to extract phenolics. Chemical procedures are used to detect the presence of total phenolics, while spectrophotometric and chromatographic techniques are utilized to identify and quantify individual phenolic compounds. This review addresses the application of different methodologies utilized in the analysis of phenolic compounds in plant-based products, including recent technical developments in the quantification of phenolics.
Thermodynamic Properties of Hexavalent Uranium Compounds
International Nuclear Information System (INIS)
Hexavalent uranium compounds are of importance as starting materials and as intermediary compounds in the preparation of compounds of nuclear interest. Recent experimental work on the thermodynamic and thermal properties, including phase diagrams, of a number of these compounds is presented and discussed in relation to practical applications. Thermodynamic data are given on the systems UO3-U3O8 and UO2 (NO3)2-H2O, based on calorimetric measurements as well as on vapour pressure measurements. Finally, data of some other materials, including the hydrates of uranium peroxide and UO2Cl2, are discussed. Although many of the thermodynamic data are consistent, a number of inconsistencies still remain to be resolved. On this basis suggestions are given for future work. (author)
The report summarizes and evaluates information relevant to a preliminary interim assessment of adverse health effects associated with specific chemicals or compounds. The Office of Emergency and Remedial Response (Superfund) uses these documents in preparing cost-benefit analyse...
Atmospheric Chemistry of Micrometeoritic Organic Compounds
Kress, M. E.; Belle, C. L.; Pevyhouse, A. R.; Iraci, L. T.
Micrometeorites approx.100 m in diameter deliver most of the Earth s annual accumulation of extraterrestrial material. These small particles are so strongly heated upon atmospheric entry that most of their volatile content is vaporized. Here we present preliminary results from two sets of experiments to investigate the fate of the organic fraction of micrometeorites. In the first set of experiments, 300 m particles of a CM carbonaceous chondrite were subject to flash pyrolysis, simulating atmospheric entry. In addition to CO and CO2, many organic compounds were released, including functionalized benzenes, hydrocarbons, and small polycyclic aromatic hydrocarbons. In the second set of experiments, we subjected two of these compounds to conditions that simulate the heterogeneous chemistry of Earth s upper atmosphere. We find evidence that meteor-derived compounds can follow reaction pathways leading to the formation of more complex organic compounds.
Stabilized lanthanum sulphur compounds. [thermoelectric materials
Reynolds, G. H.; Elsner, N. B.; Shearer, C. H. (Inventor)
Lanthanum sulfide is maintained in the stable cubic phase form over a temperature range of from 500 C to 1500 C by adding to it small amounts of calcium, barium, or strontium. This compound is an excellent thermoelectric material.
Triethyltin (TET) and trimethyltin (TMT) are neurotoxic organotin compounds which produce different patterns of toxicity in adult animals. Exposure to TET produces behavioral toxicity (decreased motor activity, grip strength, operant response rate and startle response amplitude) ...
Agricultural Compounds in Water and Birth Defects.
Brender, Jean D; Weyer, Peter J
Agricultural compounds have been detected in drinking water, some of which are teratogens in animal models. The most commonly detected agricultural compounds in drinking water include nitrate, atrazine, and desethylatrazine. Arsenic can also be an agricultural contaminant, although arsenic often originates from geologic sources. Nitrate has been the most studied agricultural compound in relation to prenatal exposure and birth defects. In several case-control studies published since 2000, women giving birth to babies with neural tube defects, oral clefts, and limb deficiencies were more likely than control mothers to be exposed to higher concentrations of drinking water nitrate during pregnancy. Higher concentrations of atrazine in drinking water have been associated with abdominal defects, gastroschisis, and other defects. Elevated arsenic in drinking water has also been associated with birth defects. Since these compounds often occur as mixtures, it is suggested that future research focus on the impact of mixtures, such as nitrate and atrazine, on birth defects. PMID:27007730
Phenolic Compounds in Four Astragalus Species
Ilina N. Krasteva
Aim: To investigate the phenolic compounds in four Astragalus species (A. hamosus, A. ponticus, A. corniculatus and A. cicer) distributed in Bulgarian flora. Study Design: Using LC-MS, HPLC, UV, NMR and HRESIMS for identification of the compounds. Place and Duration of Study: Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Sofia, Bulgaria, between May 2009 and December 2012. Methodology: LC/MS/MS analysis was performed using Agilent 1100 and API 365 t...
Antimicrobial Compounds to Combat Citrus Huanglongbing
Zhang, Muqing; Guo, Ying; Powell, Charles A.; Duan, Yongping
Citrus Huanglongbing (HLB) is associated with the fastidious bacterium,Candidatus Liberibacter, (Las) that is transmitted by a phloem-feeding insect (Citrus Psyllid). An ideal solution to combat citrus HLB is to completely eliminate the bacteria after a single course of the chemotherapy, either active directly on the bacteria or indirectly through induction of host defense compounds. Twenty-seven antimicrobial compounds were screened to test for in vivo activities against HLB bacterium while ...
Mercury compounds characterization by thermal desorption
Rumayor Villamil, Marta; Díaz Somoano, Mercedes; López Antón, María Antonia; Martínez Tarazona, María Rosa
[EN] The ability to accurately determine metal mercury content and identify different mercury species in solid samples is essential for developing remediation and control strategies. The aim of the present study is to characterize mercury compounds based on thermal desorption. For this purpose a series of samples was prepared and the operational parameters—heating velocity, carrier gas—were optimized. Fifteen commercial mercury compounds were analyzed for use as fingerprints. The results of t...
BASF Launches New Compounding Plant in China
Institute of Scientific and Technical Information of China (English)
@@ BASF, a leading international chemical company,kicked off construction of an engineering plastics compounding plant Pudong Area in Shanghai in midMay. The new facility is a world-scale plant with annual capacity of 45,000 tons. It is one of the most modern compounding plants in the world today, with "the highest environmental standards and the most efficient production capabilities available," according to a BASF official.
Medical Applications and Toxicities of Gallium Compounds
Directory of Open Access Journals (Sweden)
Christopher R. Chitambar
Full Text Available Over the past two to three decades, gallium compounds have gained importance in the fields of medicine and electronics. In clinical medicine, radioactive gallium and stable gallium nitrate are used as diagnostic and therapeutic agents in cancer and disorders of calcium and bone metabolism. In addition, gallium compounds have displayed anti-inflammatory and immunosuppressive activity in animal models of human disease while more recent studies have shown that gallium compounds may function as antimicrobial agents against certain pathogens. In a totally different realm, the chemical properties of gallium arsenide have led to its use in the semiconductor industry. Gallium compounds, whether used medically or in the electronics field, have toxicities. Patients receiving gallium nitrate for the treatment of various diseases may benefit from such therapy, but knowledge of the therapeutic index of this drug is necessary to avoid clinical toxicities. Animals exposed to gallium arsenide display toxicities in certain organ systems suggesting that environmental risks may exist for individuals exposed to this compound in the workplace. Although the arsenic moiety of gallium arsenide appears to be mainly responsible for its pulmonary toxicity, gallium may contribute to some of the detrimental effects in other organs. The use of older and newer gallium compounds in clinical medicine may be advanced by a better understanding of their mechanisms of action, drug resistance, pharmacology, and side-effects. This review will discuss the medical applications of gallium and its mechanisms of action, the newer gallium compounds and future directions for development, and the toxicities of gallium compounds in current use.
Preparation of azo compounds with solid catalysts
Corma, Avelino; García Gómez, Hermenegildo; Grirrane, Abdessamad
[EN] The present invention refers to a procedure for preparing azo compounds comprising a reaction between at least: one amine or polyamine, molecular oxygen, a catalyst comprising at least one support selected fkom at least a metal oxide of one of the elements of the groups 3,4, 5, 6, 8, 9, 11 and 13, silica, an anionic laminar compound of hydrotalcite type or its derivatives, active carbon or an organic polymer. In addition, said catalyst may contain nanoparticles of gold.
Antiviral Lead Compounds from Marine Sponges
Kenneth P. Minneman; Mandeep Kaur; Sunil Sagar
Marine sponges are currently one of the richest sources of pharmacologically active compounds found in the marine environment. These bioactive molecules are often secondary metabolites, whose main function is to enable and/or modulate cellular communication and defense. They are usually produced by functional enzyme clusters in sponges and/or their associated symbiotic microorganisms. Natural product lead compounds from sponges have often been found to be promising pharmaceutical agents. Seve...
Mass spectrometry for determination of bioactive compounds
Digital Repository Service at National Institute of Oceanography (India)
Tilvi, S.; Majik, M.S.; Singh, K.S.
cell. This type of experiment is particularly useful for monitoring groups of compounds contained within a mixture which fragment to produce common fragment ions, e.g. glycosylated peptides in a tryptic digest mixture, aliphatic hydrocarbons in an oil... in a matrix e.g. drug testing with blood or urine samples. It is not only a highly specific method but also has very high sensitivity. For known compounds, mass spectra can be used much like fingerprints. A match is extremely strong evidence...
Techniques for Analysis of Plant Phenolic Compounds
Roberts, Thomas H.; Meredith A. Wilkes; Ali Khoddami
Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules have occurred over the last 25 years. Organic solvent extraction is the main method used to extract phenolics. Chemical procedures are used to detect the pre...
Bioactive compounds in whole grain wheat
Mateo Anson, N.
Bread can be healthier! Consuming whole-grain foods can prevent cardiovascular diseases, type-2 diabetes and metabolic syndrome. This is due to bioactive compounds in whole grain, such as antioxidants and anti-inflammatory compounds. We found that the different fractions of a wheat grain vary much in their content. The external fractions of the grain, the bran and specially the aleurone, are the richest. We observed that processing the bran in whole-grain breads increased three times the leve...
Superconductivity in rare earth and actinide compounds
International Nuclear Information System (INIS)
Rare earth and actinide compounds and the extraordinary superconducting and magnetic phenomena they exhibit are surveyed. The rare earth and actinide compounds described belong to three classes of novel superconducting materials: high temperature, high field superconductors (intermetallics and layered cuprates); superconductors containing localized magnetic moments; heavy fermion superconductors. Recent experiments on the resistive upper critical field of high Tc cuprate superconductors and the peak effect in the critical current density of the f-electron superconductor CeRu2 are discussed. (orig.)
AN AROMATIC COMPOUND from CENTAUREA PTOSIMOPAPPOIDES
Centaurea ptosimopappoides was previously investigated by our groupand the presence of two new triterpenes were reported. The rare occurrence ofthis type compounds in the plants prompted us to further investigation of Centaureaptosimopappoides. In this work we report the isolation and structure determinationof an aromatic glycoside which was found in the genus Centaureafor the first time. The structure of the compound was determined by spectralmethods.Key words: Centaurea ptosimopappoides; Co...
Phenolic compounds of three unconventional Sudanese oils
Abdalbasit Mariod; Bertrand Matthäus; Karl Eichner; Hussein, Ismail H.
Background. The total amount and content of phenolic and fl avonoid compounds using the Folin-Ciocalteu and Aluminum chloride methods of the methanolic extracts of Sclerocarya birrea oil (SCO), Melon bug oil (MBO), and Sorghum bug oil (SBO) were studied. Material and methods. Dry samples of Sclerocarya birrea, Aspongopus vidiuatus and Agonoscelis pubescens were used in this study. The oil was extracted using n-hexane following AOCS method. The phenolic compounds were extracted following a...
Crystal Structure of New Heusler Compounds
Graf, Tanja; Casper, Frederick; Winterlik, Jürgen; Balke, Benjamin; FECHER, GERHARD H.; Felser, Claudia
Abstract Heusler compounds are promising materials in many fields of contemporary research. The spectrum of their possible applications ranges from magnetic and magneto-mechanical materials over semiconductors and thermoelectrics to superconductors. An important feature of the Heusler compounds is the possibility of controlling the valence electron concentration by partial substitution of elements. On the other hand, the properties also depend on the degree of ordering of the the c...
Crystal Structure of New Heusler Compounds
Graf, Tanja; Casper, Frederick; Winterlik, Jürgen; Balke, Benjamin; FECHER, GERHARD H.; Felser, Claudia
Heusler compounds are promising materials in many fields of contemporary research. The spectrum of their possible applications ranges from magnetic and magneto-mechanical materials over semiconductors and thermoelectrics to superconductors. An important feature of the Heusler compounds is the possibility of controlling the valence electron concentration by partial substitution of elements. On the other hand, the properties also depend on the degree of ordering of the the crystal structure. In...
Basics and prospective of magnetic Heusler compounds
Claudia Felser; Lukas Wollmann; Stanislav Chadov; FECHER, GERHARD H.; Parkin, Stuart S. P.
Heusler compounds are a remarkable class of materials with more than 1000 members and a wide range of extraordinary multi-functionalities including halfmetallic high-temperature ferri- and ferromagnets, multi-ferroics, shape memory alloys, and tunable topological insulators with a high potential for spintronics, energy technologies, and magneto-caloric applications. The tunability of this class of materials is exceptional and nearly every functionality can be designed. Co2-Heusler compounds s...
Botanical Compounds: Effects on Major Eye Diseases
Tuan-Phat Huynh; Mann, Shivani N.; Mandal, Nawajes A.
Botanical compounds have been widely used throughout history as cures for various diseases and ailments. Many of these compounds exhibit strong antioxidative, anti-inflammatory, and antiapoptotic properties. These are also common damaging mechanisms apparent in several ocular diseases, including age-related macular degeneration (AMD), glaucoma, diabetic retinopathy, cataract, and retinitis pigmentosa. In recent years, there have been many epidemiological and clinical studies that have demonst...
Electrochemical activation of reactions involving organometallic compounds
International Nuclear Information System (INIS)
Data on the electrochemical activation of various reactions involving organometallic compounds are generalised. Primary attention is devoted to the main types of transformation that can be performed by electrochemical electron transfer: redox activation of 16- and 18-electron complexes of transition metals, molybdenum, tungsten, and ruthenium in particular, as the first step of a broad range of reactions, electrocatalysis, mediator processes, and electrosynthesis of compounds containing carbon-metal σ-bonds
Reduced sulfur compound oxidation by Thiobacillus caldus.
Hallberg, K. B.; Dopson, M; Lindström, E B
The oxidation of reduced inorganic sulfur compounds was studied by using resting cells of the moderate thermophile Thiobacillus caldus strain KU. The oxygen consumption rate and total oxygen consumed were determined for the reduced sulfur compounds thiosulfate, tetrathionate, sulfur, sulfide, and sulfite in the absence and in the presence of inhibitors and uncouplers. The uncouplers 2,4-dinitrophenol and carbonyl cyanide m-chlorophenyl-hydrazone had no affect on the oxidation of thiosulfate, ...
Two new compounds from Xanthium strumarium.
Yin, Rong-Hua; Bai, Xue; Feng, Tao; Dong, Ze-Jun; Li, Zheng-Hui; Liu, Ji-Kai
One new lignan, fructusol A (1), and one new thiazine derivative, 2-hydroxy-xanthiazone (2), along with eight known ones, were isolated from the seeds of Xanthium strumarium. The structures of new compounds were elucidated on the basis of extensive spectroscopic methods. Meanwhile, compounds 1-3 were tested for their antifungal activities against Candida albicans (ATCC 10231) in vitro. No one showed obvious inhibitions (MIC90 > 128 μg/ml). PMID:26629595
PERFLUORINATED COMPOUNDS: EMERGING POPs WITH POTENTIAL IMMUNOTOXICITY
Corsini, Emanuela; Luebke, Robert W.; Germolec, Dori R.; DeWitt, Jamie C.
Perfluorinated compounds (PFCs) have been recognized as an important class of environmental contaminants commonly detected in blood samples of both wildlife and humans. These compounds have been in use for more than 60 years as surface treatment chemicals, polymerization aids, and surfactants. They possess a strong carbon-fluorine bond, which leads to their environmental persistence. There is evidence from both epidemiology and laboratory studies that PFCs may be immunotoxic, affecting both c...
Chemotaxis of Azospirillum Species to Aromatic Compounds
Lopez-de-Victoria, Geralyne; Lovell, Charles R.
Chemotaxis of Azospirillum lipoferum Sp 59b and Azospirillum brasilense Sp 7 and Sp CD to malate and to the aromatic substrates benzoate, protocatechuate, 4-hydroxybenzoate, and catechol was assayed by the capillary method and direct cell counts. A. lipoferum required induction by growth on 4-hydroxybenzoate for positive chemotaxis to this compound. Chemotaxis of Azospirillum spp. to all other substrates did not require induction. Maximum chemotactic responses for most aromatic compounds occu...
Carbonyl Compounds Generated from Electronic Cigarettes
Directory of Open Access Journals (Sweden)
Kanae Bekki
Full Text Available Electronic cigarettes (e-cigarettes are advertised as being safer than tobacco cigarettes products as the chemical compounds inhaled from e-cigarettes are believed to be fewer and less toxic than those from tobacco cigarettes. Therefore, continuous careful monitoring and risk management of e-cigarettes should be implemented, with the aim of protecting and promoting public health worldwide. Moreover, basic scientific data are required for the regulation of e-cigarette. To date, there have been reports of many hazardous chemical compounds generated from e-cigarettes, particularly carbonyl compounds such as formaldehyde, acetaldehyde, acrolein, and glyoxal, which are often found in e-cigarette aerosols. These carbonyl compounds are incidentally generated by the oxidation of e-liquid (liquid in e-cigarette; glycerol and glycols when the liquid comes in contact with the heated nichrome wire. The compositions and concentrations of these compounds vary depending on the type of e-liquid and the battery voltage. In some cases, extremely high concentrations of these carbonyl compounds are generated, and may contribute to various health effects. Suppliers, risk management organizations, and users of e-cigarettes should be aware of this phenomenon.
Natural compounds for pediatric cancer treatment.
Ferrucci, Veronica; Boffa, Iolanda; De Masi, Gina; Zollo, Massimo
There is a tremendous need in clinics to impair cancer progression through noninvasive therapeutic approaches. The use of natural compounds to achieve this is of importance to improve the quality of life of young patients during their treatments. This review will address the "status of the art" related to the potential of natural compounds that are undergoing investigation in combination with standard therapeutic protocols in preclinical and clinical studies and their importance for pediatric cancer treatment. The early studies of drug discovery of these natural compounds discussed here include the main targets, the cellular signaling pathways involved, and the potential modes of action. We also focus on some promising natural compounds that have shown excellent results in vitro and in vivo: Chebulagic acid, Apigenin, Norcantharidin, Saffron/Crocin, Parthenolide, Longikaurin E, Lupeol, Spongistatin 1, and Deoxy-variolin B. Additionally, we introduce the effects of several compounds from nutraceutical and functional foods, to underline their potential use as adjuvant therapies to improve therapeutic benefits. For this purpose, we have selected several compounds: Agaritine, Ganoderma and GL6 peptide, Diallyl trisulfide and Ajoene from garlic, Epigallocatechin gallate from green tea, Curcumin, Resveratrol, and Quercetin. PMID:26650503
Environmentally acceptable drill pipe thread compound
International Nuclear Information System (INIS)
Environmental concerns are prompting the petroleum industry to replace thread compounds. Traditional thread compound formulations, now widely used for more than three decades have proven effective. But all contain significant percentages (up to about 60%) of heavy metal powders. Ingredients such as copper, lead and zinc are increasingly being banned for use or dumping. This paper outlines the issues and describes the new technology which will be required in most areas during 1992. It introduces a drill pipe thread compound with unique mechanisms to achieve improved functional performance while providing environmental acceptability. Rotary shouldered compounds (and orthodox thinking) have relied upon soft, low melting point, malleable metal particles to provide connection sealing and anti-galling characteristics. The new approach uses the non-conformist approach of hard ceramic microspheres to achieve the same results. This work gives the application and general performance requirements for rotary shouldered thread compounds. It compares the new technology with traditional compounds from the standpoint of composition, functional performance, and environmental acceptability. Bomac's work now makes it possible to run a drilling project entirely free of lead, copper and zinc
Polymers containing borane or carborane cage compounds and related applications
Energy Technology Data Exchange (ETDEWEB)
Bowen, III, Daniel E; Eastwood, Eric A
Polymers comprising residues of cage compound monomers having at least one polyalkoxy silyl substituent are provided. The cage compound monomers are selected from borane cage compound monomers comprising at least 7 cage atoms and/or carborane cage compound monomers comprising 7 to 11 cage compound monomers. Such polymers can further comprise one or more reactive matrices and/or co-monomers covalently bound with the cage compound monomer residues. Articles of manufacture comprising such polymers are also disclosed.
Chemical effect on diffusion in intermetallic compounds
Chen, Yi-Ting
With the trend of big data and the Internet of things, we live in a world full of personal electronic devices and small electronic devices. In order to make the devices more powerful, advanced electronic packaging such as wafer level packaging or 3D IC packaging play an important role. Furthermore, ?-bumps, which connect silicon dies together with dimension less than 10 ?m, are crucial parts in advanced packaging. Owing to the dimension of ?-bumps, they transform into intermetallic compound from tin based solder after the liquid state bonding process. Moreover, many new reliability issues will occur in electronic packaging when the bonding materials change; in this case, we no longer have tin based solder joint, instead, we have intermetallic compound ?-bumps. Most of the potential reliability issues in intermetallic compounds are caused by the chemical reactions driven by atomic diffusion in the material; thus, to know the diffusivities of atoms inside a material is significant and can help us to further analyze the reliability issues. However, we are lacking these kinds of data in intermetallic compound because there are some problems if used traditional Darken's analysis. Therefore, we considered Wagner diffusivity in our system to solve the problems and applied the concept of chemical effect on diffusion by taking the advantage that large amount of energy will release when compounds formed. Moreover, by inventing the holes markers made by Focus ion beam (FIB), we can conduct the diffusion experiment and obtain the tracer diffusivities of atoms inside the intermetallic compound. We applied the technique on Ni3Sn4 and Cu3Sn, which are two of the most common materials in electronic packaging, and the tracer diffusivities are measured under several different temperatures; moreover, microstructure of the intermetallic compounds are investigated to ensure the diffusion environment. Additionally, the detail diffusion mechanism was also discussed in aspect of diffusion
Pharmacists' Perceptions of the Economic Value of Compounded Pharmaceuticals: A Comparison of Compounded and Commercial Pharmaceuticals in Select Disease States.
Lobb, William B; Wilkin, Noel E; Holmes, Erin R
Studies have been conducted to assess patient satisfaction with compounded pharmaceuticals and to directly compare compounded pharmaceuticals with their comparable commercial pharmaceuticals. Yet, the economic value of or potential for economic value derived from compounded pharmaceuticals relative to commercial pharmaceuticals is still not known. Therefore, the purpose of this study was to assess and compare compounding and non-compounding pharmacists' perceptions of the economic value of compounded preparations relative to commercial products. In-depth interviews with 10 compounding pharmacists and physicians who prescribe compounded prescription pharmaceutical preparations were conducted to help develop a self-administered questionnaire distributed to 50 compounding and 50 non-compounding pharmacists. Compounding and non-compounding pharmacists' perceptions differed most often in the context of compounded pharmaceuticals for pediatric patients. However, both groups responded with moderate agreement that compounded prescription treatments are more profitable for the pharmacy than commercial prescription treatments in most therapeutic areas. This research sought to understand the perception of pharmacists of areas for potential direct and indirect economic cost savings as a result of compounding. For all items whereby compounding and non-compounding pharmacists' ratings were significantly different, compounding pharmacists more strongly believed that compounding pharmaceuticals offered benefit and vice versa. The differences in ratings that were most common were those that directly compared the economic value of compounding and commercial pharmaceuticals, with compounding pharmacists more strongly agreeing with the potential cost savings associated with compounded pharmaceuticals. Based on these findings, prescription compounds are believed to have a benefit to the health system by those who provide them. Future research should proactively explore the economic
Reflectance spectroscopy of organic compounds: 1. Alkanes
Clark, R.N.; Curchin, J.M.; Hoefen, T.M.; Swayze, G.A.
Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as the first in a series of papers to build a spectral database of organic compounds for use in remote sensing studies. Applications range from mapping the environment on the Earth, to the search for organic molecules and life in the solar system and throughout the. universe. We show that the spectral reflectance properties of organic compounds are rich, with major diagnostic spectral features throughout the spectral range studied. Little to no spectral change was observed as a function of temperature and only small shifts and changes in the width of absorption bands were observed between liquids and solids, making remote detection of spectral properties throughout the solar system simpler. Some high molecular weight organic compounds contain single-bonded carbon chains and have spectra similar to alkanes even ' when they fall into other families. Small spectral differences are often present allowing discrimination among some compounds, further illustrating the need to catalog spectral properties for accurate remote sensing identification with spectroscopy.
Determination of arsenic compounds in earthworms
Energy Technology Data Exchange (ETDEWEB)
Geiszinger, A.; Goessler, W.; Kuehnelt, D.; Kosmus, W. [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry; Francesconi, K. [Odense Univ. (Denmark). Inst. of Biology
Earthworms and soil collected from six sites in Styria, Austria, were investigated for total arsenic concentrations by ICP-MS and for arsenic compounds by HPLC-ICP-MS. Total arsenic concentrations ranged from 3.2 to 17.9 mg/kg dry weight in the worms and from 5.0 to 79.7 mg/kg dry weight in the soil samples. There was no strict correlation between the total arsenic concentrations in the worms and soil. Arsenic compounds were extracted from soil and a freeze-dried earthworm sample with a methanol/water mixture (9:1, v/v). The extracts were evaporated to dryness, redissolved in water, and chromatographed on an anion- and a cation-exchange column. Arsenic compounds were identified by comparison of the retention times with known standards. Only traces of arsenic acid could be extracted from the soil with the methanol/water (9:1, v/v) mixture. The major arsenic compounds detected in the extracts of the earthworms were arsenous acid and arsenic acid. Arsenobetaine was present as a minor constituent, and traces of dimethylarsinic acid were also detected. Two dimethylarsinoyltribosides were also identified in the extracts by co-chromatography with standard compounds. This is the first report of the presence of dimethylarsinoylribosides in a terrestrial organism. Two other minor arsenic species were present in the extract, but their retention times did not match with the retention times of the available standards.