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Acidic salts are often used in foods as part of leavening agents. In this context, the acid salts are referred to as "leavening acids." Common leavening acids include cream of tartar and monocalcium phosphate.
An acidic salt can be mixed with an alkali salt (such as sodium bicarbonate or baking soda) to create baking powders which release carbon dioxide. Leavening agents can be slow-acting (e.g. sodium aluminum phosphate) which react when heated, or fast-acting (e.g., cream of tartar) which react immediately at low temperatures. Double-acting baking powders contain both slow- and fast-acting leavening agents and react at low and high temperatures to provide leavening rising throughout the baking process.
Disodium phosphate, , is used in foods and monosodium phosphate, , is used in animal feed, toothpaste and evaporated milk. | 1 | Solid-state chemistry |
There are several ways to test defoamers.
The easiest is looking at the surface foam. All that is needed is a system for generating foam. This might be done with a round pumping system with a nozzle and a cylinder or an air injection system into a cylinder. The cylinder is fitted with a scale to measure the foam height. This equipment may have a heater to control the temperature.
Entrained air can be tested with similar equipment that has a density meter that can record changes of the liquid density over time.
Drainage can be tested with a filter system for measuring the time to drain a liquid through the filter. The filter might be pressurized or have a vacuum. | 0 | Colloidal Chemistry |
Various theories concerning microemulsion formation, stability and phase behavior have been proposed over the years. For example, one explanation for their thermodynamic stability is that the oil/water dispersion is stabilized by the surfactant present and their formation involves the elastic properties of the surfactant film at the oil/water interface, which involves as parameters, the curvature and the rigidity of the film. These parameters may have an assumed or measured pressure and/or temperature dependence (and/or the salinity of the aqueous phase), which may be used to infer the region of stability of the microemulsion, or to delineate the region where three coexisting phases occur, for example. Calculations of the interfacial tension of the microemulsion with a coexisting oil or aqueous phase are also often of special focus and may sometimes be used to guide their formulation. | 0 | Colloidal Chemistry |
Foams are materials formed by trapping pockets of gas in a liquid or solid.
A bath sponge and the head on a glass of beer are examples of foams. In most foams, the volume of gas is large, with thin films of liquid or solid separating the regions of gas. Soap foams are also known as suds.
Solid foams can be closed-cell or open-cell. In closed-cell foam, the gas forms discrete pockets, each completely surrounded by the solid material. In open-cell foam, gas pockets connect to each other. A bath sponge is an example of an open-cell foam: water easily flows through the entire structure, displacing the air. A sleeping mat is an example of a closed-cell foam: gas pockets are sealed from each other so the mat cannot soak up water.
Foams are examples of dispersed media. In general, gas is present, so it divides into gas bubbles of different sizes (i.e., the material is polydisperse)—separated by liquid regions that may form films, thinner and thinner when the liquid phase drains out of the system films. When the principal scale is small, i.e., for a very fine foam, this dispersed medium can be considered a type of colloid.
Foam can also refer to something that is analogous to foam, such as quantum foam. | 0 | Colloidal Chemistry |
Excessive respiratory disease due to environmental hazards, such as radon and asbestos, has been a concern for potash miners throughout history. Potash miners are liable to develop silicosis. Based on a study conducted between 1977 and 1987 of cardiovascular disease among potash workers, the overall mortality rates were low, but a noticeable difference in above-ground workers was documented. | 1 | Solid-state chemistry |
Figure 4 shows two examples of heterodyne autocorrelation functions of scattered light from sodium polystyrene sulfate solution (NaPSS; MW 400,000; 4 mg/mL in 10 mM NaCl). The oscillating correlation function shown by Fig. 4a is a result of interference between the scattered light and the modulated reference light.
The beat of Fig. 4b includes additionally the contribution from the frequency changes of light scattered by PSS molecules under an electrical field of 40 V/cm.
Figure 5 shows heterodyne power spectra obtained by Fourier transform of the autocorrelation functions shown in Fig. 4.
Figure 6 shows plots of Doppler shift frequencies measured at various cell depth and electric field strengths, where a sample is the NaPSS solution.
These parabolic curves are called profiles of electro-osmotic flow and indicate that the velocity of the particles changed at different depth.
The surface potential of the cell wall produces electro-osmotic flow.
Since the electrophoresis chamber is a closed system, backward flow is produced at the center of the cell.
Then the observed mobility or velocity from Eq. (7) is a result of the combination of osmotic flow and electrophoretic movement.
Electrophoretic mobility analysis has been studied by Mori and Okamoto [16], who have taken into account the effect of electro-osmotic flow at the side wall.
The profile of velocity or mobility at the center of the cell is given approximately by Eq. (11) for the case where k>5.
where
: cell depth
: apparent electrophoretic velocity of particle at position z.
: true electrophoretic velocity of the particles.
: thickness of the cell
: average velocity of osmotic flow at upper and lower cell wall.
: difference between velocities of osmotic flow at upper and lower cell wall.
: , a ratio between two side lengths of the rectangular cross section.
The parabolic curve of frequency shift caused by electro-osmotic flow shown in Fig. 6 fits with Eq. (11) with application of the least squares method.
Since the mobility is proportional to a frequency shift of the light scattered by a particle and the migrating velocity of a particle as indicated by Eq. (7), all the velocity, mobility, and frequency shifts are expressed by parabolic equations.
Then the true electrophoretic mobility of a particle, the electro-osmotic mobility at the upper and lower cell walls, ware obtained.
The frequency shift caused only by the electrophoresis of particles is equal to the apparent mobility at the stationary layer.
The velocity of the electrophoretic migration thus obtained is proportional to the electric field as shown in Fig. 7.
The frequency shift increases with increase of the scattering angle as shown in Fig. 8.
This result is in agreement with the theoretical Eq. (7). | 0 | Colloidal Chemistry |
Following his PhD, Tarascon did postdoctoral research at Cornell University. He worked at Bell Labs and Bellcore from 1982 to 1994, then moved to the University of Picardie Jules Verne in 1994. He has been at the College de France since 2010. He is also credited with laying foundations of the reputable Erasmus mundus masters course in energy storage and conversion "Materials for energy storage and conversion" hosted by UPJV, Amiens in association with seven universities across the globe and several energy research networks. | 1 | Solid-state chemistry |
Goodwin was educated at Sydney Boys High School and represented Australia at the International Chemistry Olympiad in 1996, winning a gold medal.
Goodwin earned a BSc in chemistry and pure mathematics at University of Sydney (USYD) in 2002. He completed a Ph.D. in inorganic chemistry at USYD in 2004 under advisor Cameron Kepert. Goodwin earned a Ph.D. in mineral physics from University of Cambridge in 2006 under advisor Martin T. Dove. He was a junior research fellow at Trinity College, Cambridge from 2004 to 2009. Goodwin was a visiting fellow at the Australian National University in 2007. | 1 | Solid-state chemistry |
Common examples of suspensions include:
*Mud or muddy water: where soil, clay, or silt particles are suspended in water.
*Flour suspended in water.
*Kimchi suspended on vinegar.
*Chalk suspended in water.
*Sand suspended in water. | 0 | Colloidal Chemistry |
Caliche () is a sedimentary rock, a hardened natural cement of calcium carbonate that binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or semiarid regions, including in central and western Australia, in the Kalahari Desert, in the High Plains of the western United States, in the Sonoran Desert, Chihuahuan Desert and Mojave Desert of North America, and in eastern Saudi Arabia at Al-Hasa. Caliche is also known as calcrete or kankar (in India). It belongs to the duricrusts. The term is borrowed from Spanish and is originally from the Latin word , meaning lime.
Caliche is generally light-colored, but can range from white to light pink to reddish-brown, depending on the impurities present. It generally occurs on or near the surface, but can be found in deeper subsoil deposits, as well. Layers vary from a few inches to feet thick, and multiple layers can exist in a single location. A caliche layer in a soil profile is sometimes called a K horizon.
In northern Chile and Peru, caliche also refers to mineral deposits that include nitrate salts. Caliche can also refer to various claylike deposits in Mexico and Colombia. In addition, it has been used to describe some forms of quartzite, bauxite, kaolinite, laterite, chalcedony, opal, and soda niter.
A similar material, composed of calcium sulfate rather than calcium carbonate, is called gypcrust. | 1 | Solid-state chemistry |
Nickel(III) oxides are often poorly characterized and are assumed to be nonstoichiometric compounds. Nickel(III) oxide (NiO) has not been verified crystallographically. For applications in organic chemistry, nickel oxides or peroxides are generated in situ and lack crystallographic characterization. For example, "nickel peroxide" (CAS# 12035-36-8) is also closely related to or even identical with NiO(OH). | 1 | Solid-state chemistry |
Experiments performed in microgravity on the Space Shuttle Columbia suggest that the typical face-centered cubic structure may be induced by gravitational stresses. Crystals tend to exhibit the hcp structure alone (random stacking of hexagonally close-packed crystal planes), in contrast with a mixture of (rhcp) and face-centred cubic packing when allowed sufficient time to reach mechanical equilibrium under gravitational forces on Earth. Glassy (disordered or amorphous) colloidal samples have become fully crystallized in microgravity in less than two weeks. | 0 | Colloidal Chemistry |
Eye drops are saline-containing drops used on the eye. Depending on the condition being treated, they may contain steroids, antihistamines, sympathomimetics, beta receptor blockers, parasympathomimetics, parasympatholytics, prostaglandins, non-steroidal anti-inflammatory drugs (NSAIDs), antibiotics or topical anesthetics. Eye drops sometimes do not have medications in them and are only lubricating and tear-replacing solutions. | 1 | Solid-state chemistry |
Currently utilized implants take a great deal of time to integrate with the body after the initial surgical procedure occurs. True adhesion between the implant and the bone has been difficult to achieve and, unfortunately, success rates of implant fixation are low due to the implant's failure to achieve long-term osseointegration into the bone. With an increasing number of individuals requiring orthopedic implants, the development of materials with structural and biological potential to improve osseointegration is crucial. Utilization of titanium-based foams present one way to potentially improve the bioactivity and reduce stress-shielding effects of currently employed bioimplant materials.
The problem of osseointegration is best understood by examining the process of natural bone growth. In the body, bone and tissues experience self-regeneration, and structural modifications occur normally in response to environmental stimuli. Successful osseointegration occurs in three main stages that follow a natural biologically determined procedure: 1) incorporation of the implant into the bone's formation, 2) adaption of the new bone mass to carry weight and 3) remodeling of the new bone structure. The first stage in this process is the most crucial for overall success; the implant and the bone must form a rapid connection, and this bond must be strong and enduring. Owing to its porous structure, a titanium metal foam implant may be able to achieve close fixation with the bone and will decrease patient recovery time considerably. Essentially, the foam becomes an extracellular matrix in the body as tissue is integrated into it. Today, the implants most commonly used for bone replacement lack the ability to promote these characteristics, which are found in natural bone and, as a result, the implants have limited lifetimes. This phenomenon of osseointegration works similarly to direct fracture healing. However, instead of a bone fragment-end reconnecting to bone, the fragment-end connects to an implant surface. In a study on fibroblastic interactions with high-porosity Ti6Al4V alloy, the metal foam was supportive of cell attachment and proliferation, migration through the porous network, and proved capable of sustaining a large cell population. | 0 | Colloidal Chemistry |
Culture techniques and media vary depending upon the requirements of the fungal isolate involved, however the general procedure consist of the following: fungal hyphae are typically placed in liquid growth media and placed in shake culture until the fungal culture has increased in biomass. The fungal hyphae are removed from the growth media, washed with distilled water to remove the growth media, placed in distilled water and incubated on shake culture for 24 to 48 hours. The fungal hyphae are separated from the supernatant, and an aliquot of the supernatant is added to 1.0 mM ion solution. The ion solution is then monitored for 2 to 3 days for the formation of nanoparticles. Another common culture technique is to add washed fungal hyphae directly into 1.0 mM ion solution instead of utilizing the fungal filtrate. Silver nitrate is the most widely used source of silver ions, but silver sulfate has also been utilized. Choloroauric acid is generally used as the source of gold ions at various concentrations (1.0 mM and 250 mg to 500 mg of Au per liter). Cadmium sulfide nanoparticle synthesis for F. oxysporum was conducted using a 1:1 ratio of Cd and SO at a 1 mM concentration. Gold nanoparticles can vary in shape and size depending on the pH of the ion solution. Gericke and Pinches (2006) reported that for V. luteoalbum small (cc.10 nm) spherical gold nanoparticles are formed at pH 3, larger (spherical, triangular, hexagon and rods) gold nanoparticles are formed at pH 5, and at pH 7 to pH 9 the large nanoparticles tend to lack a defined shape. Temperature interactions for both silver and gold nanoparticles were similar; a lower temperature resulted in larger nanoparticles while higher temperatures produced smaller nanoparticles. | 0 | Colloidal Chemistry |
The most effective self-assembly director is a combination of external force fields. If the fields and conditions are optimized, self-assembly can be permanent and complete. When a field combination is used with nanoparticles that are tailored to be intrinsically responsive, the most complete assembly is observed. Combinations of fields allow the benefits of self-assembly, such as scalability and simplicity, to be maintained while being able to control orientation and structure formation. Field combinations possess the greatest potential for future directed self-assembly work. | 0 | Colloidal Chemistry |
Potash deposits are located throughout the world. , deposits are being mined in Canada, Russia, China, Belarus, Israel, Germany, Chile, the United States, Jordan, Spain, the United Kingdom, Uzbekistan and Brazil, with the most significant deposits present under the great depths of the Prairie Evaporite Formation in Saskatchewan, Canada.
The Permian Basin deposit includes the major mines outside of Carlsbad, New Mexico, to the worlds purest potash deposit in Lea County, New Mexico (near the Carlsbad deposits), which is believed to be roughly 80% pure. (Osceola County, Michigan, has deposits 90+% pure; the only mine there was converted to salt production, however.) Canada is the largest producer, followed by Russia and Belarus. The most significant reserve of Canadas potash is located in the province of Saskatchewan and is mined by The Mosaic Company, Nutrien and K+S.
In China, most potash deposits are concentrated in the deserts and salt flats of the endorheic basins of its western provinces, particularly Qinghai. Geological expeditions discovered the reserves in the 1950s but commercial exploitation lagged until Deng Xiaopings Reform and Opening Up Policy in the 1980s. The 1989 opening of the Qinghai Potash Fertilizer Factory in the remote Qarhan Playa increased Chinas production of potassium chloride sixfold, from less than a year at Haixi and Tanggu to just under a year.
In 2013, almost 70% of potash production was controlled by Canpotex, an exporting and marketing firm, and the Belarusian Potash Company. The latter was a joint venture between Belaruskali and Uralkali, but on July 30, 2013, Uralkali announced that it had ended the venture. | 1 | Solid-state chemistry |
Nanoparticles often develop or receive coatings of other substances, distinct from both the particles material and of the surrounding medium. Even when only a single molecule thick, these coatings can radically change the particles properties, such as and chemical reactivity, catalytic activity, and stability in suspension. | 0 | Colloidal Chemistry |
Electrostatic coalescers use electrical fields to induce droplet coalescence in water-in-crude-oil emulsions to increase the droplet size. The squared dependence of droplet diameter in Stokes' law, increase the settling speed and destabilizes the emulsion. The effects on the water droplet arise from the very different dielectric properties of the conductive water droplets dispersed in the insulating oil. Water droplets have a permittivity that is much higher than the surrounding oil. Furthermore, water with dissolved salt is also a very good conductor. When an uncharged droplet is subjected to an AC electric field, the field will polarize the droplet, creating an electric field around the droplet to counteract the external field. As the water droplet is very conductive, the induced charges will reside on the surface. The droplet has no net charge but one positive and one negative side. Inside the droplet, the electric field is zero. When two droplets with induced dipoles get close to each other, they will experience a force pulling the droplets closer until they coalesce.
In oil production, co-produced water is mixed with the oil in choke valves and process equipment producing water-in-oil emulsions. The amount of water increases during the production life of the reservoir. The emulsions are destabilized using gravitational separators, and the settling rates are increased by applying heat, demulsifiers, and AC electric fields. The AC electric field gives rise to attractive forces between water droplets and increases the probability of coalescence at contact. According to Stokes' law, the settling rate increases proportionally with the square of the drop diameter. By promoting coalescence of small water droplets, the settling rate can be greatly increased. The water content is normally reduced to less than 0.5 vol% if this is the final treatment stage before the crude oil is exported.
Typical electrostatic coalescers are large settling tanks containing electrodes and operate under laminar-flow conditions with bare electrodes that may be vulnerable to short circuiting. An alternative to this type of coalescer is a flow through pre-coalescer that is installed upstream in a separator tank. In the Compact Electrostatic Coalescer, droplet coalescence is achieved by applying AC electric fields (50–60 Hz) to water-in-oil emulsions under turbulent-flow conditions. The turbulence increases the collision frequency between the water drops. The electrodes are insulated to prevent short circuiting, and permit water contents of up to 40% as well as water slugs. The equipment is a separate flow-through electrostatic treatment section installed upstream of a gravity separator to improve the performance. By keeping the treatment and settling sections separate, a compact electrostatic coalescer can be obtained that can also be retrofitted.
Liquid-liquid coalescers are also widely used in the oil refining industry to remove the last traces of contaminants like amine or caustic from intermediate products in oil refineries, and also for the last stage dewatering of final products like kerosene (jet fuel), LPG, gasoline and diesel to less than 15 mW free water in the hydrocarbon phase. These coalescers are often electrostatic type, in which a DC electrical field encourages the water droplets to coalesce, thus settling by gravity. | 0 | Colloidal Chemistry |
* Science of Whole Person Healing: Proceedings of the First Interdisciplinary International Conference (2003, contributor), iUniverse, .
* Observations and Studies of the Healing Efficacy of the Life Vessel (2012) [2009]. | 1 | Solid-state chemistry |
Finally, the bioactive molecule of interest is loaded into the carbohydrate layer. This process typically occurs through either lyophilization or passive adsorption, and the fully functionalized aquasome is then characterized. | 0 | Colloidal Chemistry |
3D cell culturing by Magnetic Levitation Method (MLM) is the application of growing 3D tissue by inducing cells treated with magnetic nanoparticle assemblies in spatially varying magnetic fields, using neodymium magnetic drivers and promoting cell-to-cell interactions by levitating the cells up to the air/liquid interface of a standard petri dish. The magnetic nanoparticle assemblies consist of magnetic iron oxide nanoparticles, gold nanoparticles, and the polymer polylysine. 3D cell culturing is scalable, with the capability of culturing as few as 500 cells up to millions of cells, or from a single dish to high-throughput low volume systems. Once magnetized cultures are generated, they can also be used as the building block material, or the "ink" for the magnetic 3D bioprinting process. | 0 | Colloidal Chemistry |
This distortion can be treated in the same fashion, using the triple product to determine whether or not the distortion from the undistorted linear D symmetry will produce a symmetry-allowed interaction (and therefore, whether or not the distortion will occur). | 1 | Solid-state chemistry |
A prescription drug (Cystadane) containing betaine has limited use for oral treatment of genetic homocystinuria to lower levels of homocysteine in circulating blood. | 0 | Colloidal Chemistry |
Surfactants play an important role in droplet-based microfluidics in the stabilization of the droplets, and the prevention of the fusion of droplets during incubation. | 0 | Colloidal Chemistry |
Kanishka Biswas is an Associate Professor in the New Chemistry Unit at Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore with research interests focused on renewable energy and clean environment. The areas in which he has worked include solid state inorganic chemistry of metal chalcogenides, thermoelectric materials, 2D layered materials, topological insulators. | 1 | Solid-state chemistry |
Samarium(III) arsenide is a binary inorganic compound of samarium and arsenic with the chemical formula SmAs. | 1 | Solid-state chemistry |
Paul Alivisatos was born in Chicago, Illinois, to a Greek family, where he lived until the age of 10, when his family moved to Athens, Greece. Alivisatos has said of his years in Greece that it was a great experience for him because he had to learn the Greek language and culture then catch up with the more advanced students. "When I found something very interesting it was sometimes a struggle for me to understand it the very best that I could," he has said of that experience. "That need to work harder became an important motivator for me." Alivisatos returned to the United States to attend the University of Chicago in the late 1970s.
In 1981, Alivisatos earned a B.A. with honors in chemistry from the University of Chicago. In 1986, he received a Ph.D. in physical chemistry from the University of California, Berkeley, where he worked under Charles Harris. His Ph.D. thesis concerned the photophysics of electronically excited molecules near metal and semiconductor surfaces. He then joined AT&T Bell Labs working with Louis E. Brus, and began research in the field of nanotechnology.
Alivisatos returned to Berkeley in 1988 as an assistant professor of chemistry, becoming associate professor in 1993 and professor in 1995. He served as Chancellor's Professor from 1998 to 2001, and added an appointment as a professor of materials science and engineering in 1999.
Alivisatos affiliation with Lawrence Berkeley National Lab (or Berkeley Lab) began in 1991 when he joined the staff of the Materials Sciences Division. From 2005 to 2007 Alivisatos served as Berkeley Labs Associate Laboratory Director for the Physical Sciences area. In 2008, he served as Deputy Lab Director under Berkeley Lab Director Steven Chu, and then as interim director when Chu stepped down to become the Secretary of Energy. He was named the seventh Director of Berkeley Lab on November 19, 2009, by the University of California Board of Regents on the recommendation of UC President Mark Yudof and with the concurrence of the U.S. Department of Energy. He played a critical role in the establishment of the Molecular Foundry, a U.S. Department of Energys Nanoscale Science Research Center; and was the facilitys founding director.
Energy Secretary, Nobel laureate, and fellow Berkeley alumnus Steven Chu noted that Alivisatos is "an incredible scientist with incredible judgment on a variety of issues. He's level-headed and calm, and he has an ability to inspire people…[and he can] take projects from material science to real-world applications." | 1 | Solid-state chemistry |
Solubility of salts in organic solvents is a function of both the cation and the anion. The solubility of cations in organic solvents can be enhanced when the anion is lipophilic. Similarly, the solubility of anions in organic solvents is enhanced with lipophilic cations. The most common lipophilic cations are quaternary ammonium cations, called "quat salts".
Many cationic organometallic complexes are isolated with inert, noncoordinating counterions. Ferrocenium tetrafluoroborate is one such example. | 1 | Solid-state chemistry |
In 2017, the ABCs current affairs program Four Corners reported that the storage and use of firefighting foams containing perfluorinated surfactants at Australian Defence Force facilities around Australia had contaminated nearby water resources. In 2019, remediation efforts at RAAF Base Tindal and the adjacent town of Katherine were ongoing. In the 2022 Australian federal budget $428million was allocated for works at HMAS Albatross', RAAF Base Amberley, RAAF Base Pearce and RAAF Base Richmond including funding to remediate PFAS contamination. | 0 | Colloidal Chemistry |
Synthetic foams are based on synthetic surfactants. They provide better flow and spreading over the surface of hydrocarbon-based liquids, for faster knockdown of flames. They have limited post-fire security and are toxic groundwater contaminants.
* Aqueous film forming foams (AFFF) are water-based and frequently contain hydrocarbon-based surfactants such as sodium alkyl sulfate, and fluorosurfactants, such as fluorotelomers, perfluorooctanoic acid (PFOA), or perfluorooctanesulfonic acid (PFOS).
* Alcohol-resistant aqueous film-forming foams (AR-AFFF) are foams resistant to the action of alcohols and can form a protective film.
*Fluorine-free foams (FFF, also called F3) are mostly based on hydrocarbon surfactants and are free of any fluorosurfactant. | 0 | Colloidal Chemistry |
Krebs' scientific achievements are centered in the fields of inorganic chemistry, bioinorganic chemistry, and structural chemistry. Starting with his thesis on trithiocarbonic acid and its chemistry, and supported by his profound experience gained during his postdoctoral work at Brookhaven National Laboratory, he was one of the pioneers of chemical crystallography in Germany in the sixties. In this context he was successful in his synthetic investigations on novel polynuclear metal-sulphur compounds, on chalcogen-halogen compounds and on transition metal oxo compounds which were supported by most innovative structural investigations with X-ray and neutron diffraction methods. In the field of physically relevant synthetic solid state chemistry he is internationally known for his pioneering development of boron-chalcogen chemistry. Besides novel binary and ternary boron-sulfur and boron-selenium compounds he developed new ionic conductors on the basis of lithium chalcogenoborates.
His work in bioinorganic chemistry is centered mainly on investigations of the synthesis, structure and function of model compounds for metalloenzymes such as the purple acid phosphatases (iron, zinc), glucose isomerase (cobalt, zinc) and copper type-3 enzymes (catechol oxidase, tyrosinase). These investigations have led to catalytically active models as thermally stable and selective analogues for metalloenzymes. One of the achievements is the establishment of bio-analogous chemosensor systems for the analysis of catecholamines. Further investigations include a large number of mono- and polynuclear sulphur complexes of transition metals such as iron, nickel, cobalt, zinc or molybdenum.
They are significant contributions to the understanding of the function and structure of important metal-sulphur proteins such as ferredoxins, nitrogenases and metallothioneins. An important recent research project concerns the synthesis and practical development of novel platinum complexes as possible antitumor agents. Bernt Krebs was able to develop a number of highly interesting new compounds with promising properties, e.g., without nephrotoxic side effects.
His structural investigations are significant contributions to the understanding of the mechanisms of the interaction of platinum agents with DNA. The contributions of Bernt Krebs to the methods and applications of crystal structure analysis with X-ray and neutron diffraction and to X-ray absorption spectroscopy are outstanding. His pioneering crystal structures of purple acid phosphatase from kidney bean and of catechol oxidase from sweet potatoes have become classical results of metalloenzyme research papers. | 1 | Solid-state chemistry |
García-Garibay received his B.S. from the University of Michoacán, Mexico, in 1982. After completing a combined degree in Chemistry, Biology, and Pharmacy, García-Garibay went on to get a PhD degree in Chemistry at the University of British Columbia, where he joined the group of John Scheffer. After that, he joined the group of Nicholas Turro as a postdoctoral fellow at Columbia University.
García-Garibay received an Arthur C. Cope Scholar Award in 2015. | 1 | Solid-state chemistry |
In chemistry, a hydrobromide is an acid salt resulting, or regarded as resulting, from the reaction of hydrobromic acid with an organic base (e.g. an amine). The compounds are similar to hydrochlorides.
Some drugs are formulated as hydrobromides, e.g. eletriptan hydrobromide. | 1 | Solid-state chemistry |
Professor Mukherjeeled a very illustrious life holding several important positions. Some of them are :
Professor of Chemistry, University College of Science and Technology, Calcutta Director, Indian Agricultural Research Institute founder Director"; Central Building Research Institute, Roorkee ; Part-time Scientific Adviser, Departments of Agriculture, Animal Husbandry, Irrigation, Forest, Community Development, Government of West Bengal; Administrator, Boardof Secondary Education, West Bengal; Member. Union Public Service Commission ; President, State College of Agriculture of West
Bengal ; President, Indian Science Congress Association ; President, Indian Chemical Society ; President, Indian Society of Soil Science ; President, Indian Association for the Cultivation of Science ; Founder -~Honorary~ Secretary of Indian Chemical Society ; President, Indian Science News Association ; President, Indian Society of Soil and Water Conservation; Vice-President, Indian Statistical Institute; Member, Foundation Committee; Fellow, Indian National Science Academy ; Fellow, Asiatic Society ; Life. member, Chemical Society, London ; Member, General Assembly, Board of Executive Committee of the International Council of
Scientific Unions ; Chairman, Export Fertilizer Committee ; Chairman, Homeopathic Enquiry Committee ; Chairman, Research Committee, Department of Agriculture, Govt. of West Bengal; Chairman Land Utilization Board,Govt.of West Bengal; Chairman, Research Committee, CSIR; Member, Technical Committee and Board, CSIR ; Member, Senate and Board of Accounts, University of Calcutta ; Secretary (Science), Re organisation Committee, University of Calcutta ; Chairman, several scientific committees of ICAR ; Leader of the Indian Delegation to :
(i)the VI Committees of the International Society of Soil Science, Holland
(ii)the Third Congress of the International Society of Soil Science, Oxford
(iii) the Imperial Agricultural Bureau Review Conference, London ; Member, Indian Scientific Mission of the Govt. of India to UK, USA, and Canada ; Member, Indian
Delegation to the Royal Society Empire Scientific and British Commonwealth Official Scientific Conference, London ;Member. Indian Delegation to the United National Scientific Conference on the Conservation and Utilization of Resources, Lake Success, USA; Member, Indian Delegation to the Second Congress of the Pan Indian Ocean Scientific Association, Perth, Australia ; Delegate to the Conference on Tropical and Subtropical Soils, Rothamsted ; President, Board of Trustees; Surendranath Trust, Calcutta. | 0 | Colloidal Chemistry |
Ibers received his B.S. and Ph.D. degrees at California Institute of Technology. His thesis, awarded in 1954, was done under the direction of Verner F. Schomoker and James H. Sturdivant. | 1 | Solid-state chemistry |
A study published in Science in August 2022 indicated that perfluoroalkyl carboxylic acids (PFCAs) can be mineralized via heating in a polar aprotic solvent such as dimethyl sulfoxide. It reported that heating PFCAs in an 8 to 1 mixture of dimethyl sulfoxide and water at in the presence of sodium hydroxide caused the removal of the carboxylic acid group at the end of the carbon chain, creating a perfluoroanion that mineralizes into sodium fluoride and other salts such as sodium trifluoroacetate, formate, carbonate, oxalate, and glycolate. The process does not work on perfluorosulfonic acids such as PFOS. A more recent study published in Chemical Science shows breakdown of C-F bonds and their mineralization as YF or YF clusters. Another study in the Journal of the American Chemical Society described the PFAs breakdown using metal-organic frameworks (MOFs). | 0 | Colloidal Chemistry |
Listed below are the cell types (primary and cell lines) that have been successfully cultured by the magnetic levitation method. The second table is the same but with images included.
Same table as above, but with images. | 0 | Colloidal Chemistry |
It has been revealed by unclassified official sources that Fogbank was originally manufactured in Facility 9404-11 of the Y-12 National Security Complex in Oak Ridge, Tennessee, from 1975 until 1989, when the final batch of W76 warheads was completed. After that, the facility was deactivated, and finally slated for decommissioning by 1993. Only a small pilot plant was left, which had been used to produce small batches of Fogbank for testing purposes.
In 1996, the US government decided to replace, refurbish, or decommission large numbers of its nuclear weapons. Accordingly, the Department of Energy established a refurbishment program to extend the service lives of older nuclear weapons. In 2000, the NNSA specified a life-extension program for W76 warheads that would enable them to remain in service until at least 2040.
It was soon realized that the Fogbank material was a potential source of problems for the program, as few records of its manufacturing process had been retained when it was originally manufactured in the 1980s, and nearly all staff members who had expertise in its production had either retired or left the agency. The NNSA briefly investigated sourcing a substitute for Fogbank, but eventually decided that since Fogbank had been produced previously, they would be able to repeat it. Additionally, "Los Alamos computer simulations at that time were not sophisticated enough to determine conclusively that an alternate material would function as effectively as Fogbank," according to a Los Alamos publication.
Manufacture involves the moderately toxic, highly volatile solvent acetonitrile, which presents a hazard for workers (causing three evacuations in March 2006 alone).
With Facility 9404-11 long since decommissioned, a new production facility was required. Delays arose during its construction. Engineers repeatedly encountered failure in their efforts to produce Fogbank. As multiple deadlines expired, and the schedule was pushed back repeatedly, the NNSA eventually invested $23 million to find an alternative to Fogbank.
In March 2007, engineers devised a manufacturing process for Fogbank. Unfortunately, the material turned out to have problems when tested, and in September 2007 the Fogbank project was upgraded to "Code Blue" status by the NNSA, making it a major priority. In 2008, following the expenditure of a further $69 million, the NNSA finally managed to manufacture Fogbank, and 7 months later, the first refurbished warhead was provided to the US Navy, nearly a decade after the commencement of the refurbishment program. In May 2009 a US Navy spokesman said that they had not received any refurbished weapons. The Energy Department stated that the current plan was to begin shipping refurbished weapons in the fall of 2009, two years behind schedule.
The experience of reverse engineering Fogbank produced some improvements in scientific knowledge of the process. The new production scientists noticed that certain problems in production resembled those noted by the original team. These problems were traced to a particular impurity in the final product that was required to meet quality standards. A root cause investigation showed that input materials were subject to cleaning processes that had not existed during the original production run. This cleaning removed a substance that generated the required impurity. With the implicit role of this substance finally understood, the production scientists could control output quality better than during the original run.
The W76 life-extension project was completed in December 2018, when 800 W76s were upgraded to the W76-1 design. It is unclear whether the new W76-2 uses Fogbank. | 0 | Colloidal Chemistry |
Even though the surface tension can be greatly reduced by pulmonary surfactant, this effect will depend on the surfactants concentration on the interface. The interface concentration has a saturation limit, which depends on temperature and mixture composition. Because during ventilation there is a variation of the lung surface area, the surfactants interface concentration is not usually at the level of saturation. The surface increases during inspiration, which consequently opens space for new surfactant molecules to be recruited to the interface. Meanwhile, during expiration the surface area decreases at a rate which is always in excess of the rate at which the surfactant molecules are driven from the interface into the water film. Thus, the surfactant density at the air water interface remains high and is relatively preserved throughout expiration, decreasing the surface tension even further. This also explains why the compliance is greater during expiration than during inspiration.
SP molecules contribute to increasing the surfactant interface adsorption kinetics, when the concentration is below the saturation level. They also make weak bonds with the surfactant molecules at the interface and hold them longer there when the interface is compressed. Therefore, during ventilation, surface tension is usually lower than at equilibrium. Therefore, the surface tension varies according to the volume of air in the lungs, which protects them from atelectasis at low volumes and tissue damage at high volume levels. | 0 | Colloidal Chemistry |
Wu's background is in advanced materials development including the development of novel materials for energy-related applications (hydrogen-storage and full cell), synthesis and characterization of new materials for nanoelectronics applications, and the study of materials used for indoor air purification. Wu is also experienced in solid state physics and chemistry including X-ray and neutron scattering, electron microscopy, and thermal analysis. | 1 | Solid-state chemistry |
The water in and around at least 126 U.S. military bases has been contaminated by high levels of PFASs because of their use of firefighting foams since the 1970s, according to a study by the U.S. Department of Defense. Of these, 90 bases reported PFAS contamination that had spread to drinking water or groundwater off the base. A 2022 Pentagon report acknowledged that approximately 175,000 U.S. military personnel at two dozen American military facilities drank water contaminated by PFAS that exceeded the U.S. EPA limit. However, according to an analysis of the Pentagon report by the non-partisan Environmental Working Group, the Pentagon report downplayed the number of people exposed to PFAS, which was much higher, probably in excess of 640,000 at 116 military facilities, than the number advanced by the Pentagon report. The EWG found that the Pentagon also omitted from its report some types of diseases that are likely to be caused by PFAS exposure, such as testicular cancer, kidney disease, and fetal abnormalities. | 0 | Colloidal Chemistry |
Nanocomposite hydrogels (NC gels) are nanomaterial-filled, hydrated, polymeric networks that exhibit higher elasticity and strength relative to traditionally made hydrogels. A range of natural and synthetic polymers are used to design nanocomposite network. By controlling the interactions between nanoparticles and polymer chains, a range of physical, chemical, and biological properties can be engineered. The combination of organic (polymer) and inorganic (clay) structure gives these hydrogels improved physical, chemical, electrical, biological, and swelling/de-swelling properties that cannot be achieved by either material alone. Inspired by flexible biological tissues, researchers incorporate carbon-based, polymeric, ceramic and/or metallic nanomaterials to give these hydrogels superior characteristics like optical properties and stimulus-sensitivity which can potentially be very helpful to medical (especially drug delivery and stem cell engineering) and mechanical fields.
Nanocomposite hydrogels are not to be confused with nanogel, a nanoparticle composed of a hydrogel. | 0 | Colloidal Chemistry |
Again, similar as for absolute permittivity, relative permittivity for lossy materials can be formulated as:
in terms of a "dielectric conductivity" σ (units S/m, siemens per meter), which "sums over all the dissipative effects of the material; it may represent an actual [[Electrical conductivity|[electrical] conductivity]] caused by migrating charge carriers and it may also refer to an energy loss associated with the dispersion of ε′ [the real-valued permittivity]" ( p. 8). Expanding the angular frequency and the electric constant , which reduces to:
where λ is the wavelength, c is the speed of light in vacuum and = 59.95849 Ω ≈ 60.0 Ω is a newly introduced constant (units ohms, or reciprocal siemens, such that σλκ = ε remains unitless). | 0 | Colloidal Chemistry |
Direct observation of phonon-polariton propagation was made possible by real-space imaging, in which the spatial and temporal profiles of phonon-polaritons are imaged onto a CCD camera using Talbot phase-to-amplitude conversion. This by itself was an extraordinary breakthrough. It was the first time that electromagnetic waves were imaged directly, appearing much like ripples in a pond when a rock plummets through the water's surface (see Fig. 3). Real-space imaging is the preferred detection technique in polaritonics, though other more conventional techniques like optical Kerr-gating, time resolved diffraction, interferometric probing, and terahertz field induced second-harmonic generation are useful in some applications where real-space imaging is not easily employed. For example, patterned materials with feature sizes on the order of a few tens of micrometres cause parasitic scattering of the imaging light. Phonon-polariton detection is then only possible by focusing a more conventional probe, like those mentioned before, into an unblemished region of the crystal. | 1 | Solid-state chemistry |
In Australia, over 97% of the population live in an area that bans expanded polystyrene. Between 2021-2023, the Australian Capital Territory, New South Wales, Queensland, South Australia, Victoria, and Western Australia enacted bans.
Nigeria's states of Lagos and Abia introduced bans in January 2024, with an initial transition period of three weeks. The state of Oyo introduced a ban in March 2024.
Municipal bans in the Philippines are in effect in Bailen, Boracay, Caloocan, Cordova, El Nido, Las Piñas, Makati, Mandaluyong City, Muntinlupa, Quezon City, and Tacloban.
In the United Arab Emirates, the municipal government of Dubai announced a ban affecting polystyrene in 2025, and all single-use plastic food containers in 2026. | 0 | Colloidal Chemistry |
A nanoparticle is defined as having one dimension 100 nm or less in size. Environmentally toxic or biologically hazardous reducing agents are typically involved in the chemical synthesis of nanoparticles so there has been a search for greener production alternatives. Current research has shown that microorganisms, plant extracts, and fungi can produce nanoparticles through biological pathways. The most common nanoparticles synthesized by fungi are silver and gold, however fungi have been utilized in the synthesis other types of nanoparticles including zinc oxide, platinum, magnetite, zirconia, silica, titanium, and cadmium sulfide and cadmium selenide quantum dots. | 0 | Colloidal Chemistry |
Phospholipid liposomes are used as targeted drug delivery systems. Hydrophilic drugs can be carried as solution inside the SUVs or MLVs and hydrophobic drugs can be incorporated into lipid bilayer of these liposomes. If injected into circulation of human/animal body, MLVs are preferentially taken up phagocytic cells, and thus drugs can be targeted to these cells. For general or overall delivery, SUVs may be used. For topical applications on skin, specialized lipids like phospholipids and sphingolipids may be used to make drug-free liposomes as moisturizers, and with drugs such as for anti-ultraviolet radiation applications.
In biomedical research, unilamellar liposomes are extremely useful to study biological systems and mimicking cell functions. As a living cell is very complicated to study, unilamellar liposomes provide a simple tool to study membrane interaction events such as membrane fusion, protein localization in the plasma membrane, study ion channels, etc. | 0 | Colloidal Chemistry |
Gold chalcogenides are compounds formed between gold and one of the chalcogens, elements from group 16 of the periodic table: oxygen, sulfur, selenium, or tellurium.
*Gold(III) oxide, AuO. Decomposes into gold and oxygen above 160 °C, and dissolves in concentrated alkalis to form solutions which probably contain the [Au(OH)] ion
*Gold(I) sulfide, AuS. Formed by reaction of hydrogen sulfide with gold(I) compounds.
*Gold(III) sulfide, AuS, claimed material but unsubstantiated.
*Gold tellurides: AuTe, AuTe, and AuTe (approximate formulæ) are known as non-stoichiometric compounds. They show metallic conductivity. AuTe is a superconductor at 1.62 K.
Gold telluride minerals, such as calaverite and krennerite (AuTe), petzite (AgAuTe), and sylvanite (AgAuTe), are minor ores of gold (and tellurium). See telluride minerals for more information. | 1 | Solid-state chemistry |
Hazens wife, Margee (née Margaret Joan Hindle), is a science writer and published historian. Her late father, Howard Brooke Hindle, PhD (1918–2001), was a historian who studied the role of material culture in the history of the United States and served as Director of the National Museum of American History from 1974 to 1978. Hazens late brother, Dan Chapin Hazen, PhD (1947–2015), was an academic research librarian who had been affiliated with the libraries at Harvard, and was particularly recognized for his accomplishments to the Center for Research Libraries and advocacy of collections from Latin America. Harvard has memorialized Dan Hazen by establishing two chairs in his name.
The Hazens have two children: Benjamin Hindle Hazen (born 1976) and Elizabeth Brooke Hazen (born 1978). | 1 | Solid-state chemistry |
The term salinity is, for oceanographers, usually associated with one of a set of specific measurement techniques. As the dominant techniques evolve, so do different descriptions of salinity. Salinities were largely measured using titration-based techniques before the 1980s. Titration with silver nitrate could be used to determine the concentration of halide ions (mainly chlorine and bromine) to give a chlorinity. The chlorinity was then multiplied by a factor to account for all other constituents. The resulting Knudsen salinities are expressed in units of parts per thousand (ppt or ‰).
The use of electrical conductivity measurements to estimate the ionic content of seawater led to the development of the scale called the practical salinity scale 1978 (PSS-78). Salinities measured using PSS-78 do not have units. The suffix psu or PSU (denoting practical salinity unit) is sometimes added to PSS-78 measurement values. The addition of PSU as a unit after the value is "formally incorrect and strongly discouraged".
In 2010 a new standard for the properties of seawater called the thermodynamic equation of seawater 2010 (TEOS-10) was introduced, advocating absolute salinity as a replacement for practical salinity, and conservative temperature as a replacement for potential temperature. This standard includes a new scale called the reference composition salinity scale. Absolute salinities on this scale are expressed as a mass fraction, in grams per kilogram of solution. Salinities on this scale are determined by combining electrical conductivity measurements with other information that can account for regional changes in the composition of seawater. They can also be determined by making direct density measurements.
A sample of seawater from most locations with a chlorinity of 19.37 ppt will have a Knudsen salinity of 35.00 ppt, a PSS-78 practical salinity of about 35.0, and a TEOS-10 absolute salinity of about 35.2 g/kg. The electrical conductivity of this water at a temperature of 15 °C is 42.9 mS/cm.
On the global scale, it is extremely likely that human-caused climate change has contributed to observed surface and subsurface salinity changes since the 1950s, and projections of surface salinity changes throughout the 21st century indicate that fresh ocean regions will continue to get fresher and salty regions will continue to get saltier.
Salinity is serving as a tracer of different masses. Surface water is pulled in to replace the sinking water, which in turn eventually becomes cold and salty enough to sink. Salinity distribution contributes to shape the oceanic circulation. | 1 | Solid-state chemistry |
Polyaniline nanofibers have been shown to be incredibly successful as chemical sensors, as they perform better than conventional polyaniline films in numerous tests. This performance difference has been attributed to their high surface area, porosity, and small diameters which enhance diffusion of materials through the nanofibers. Polyaniline nanofiber sensors function through a change in resistance. The polyaniline nanofiber film is placed on an electrode, where a current flows through. The resistance of the electrode changes when the target interacts with the film, which allows the target to be detected.
One study proposes the creation of hydrogen gas sensors using polyaniline nanofibers. It shows that both doped and dedoped polyaniline nanofibers can be used for detection of hydrogen gas through resistance changes, but the dedoped nanofibers were more stable and had better reproducibility.
Another study shows the potential of polyaniline nanofibers as NO gas sensors. NO gas acts as a strong oxidizing agent to the emeraldine form of polyaniline nanofibers, which causes resistance changes greater than three orders of magnitude at 100 ppm.
Sensing targets can be expanded through adding materials to the polyaniline nanofibers. One study proposes polyaniline nanofiber composites with metal salts for the detection of hydrogen sulfide. Hydrogen sulfide is a weak acid that is dangerous at low ppm, but polyaniline nanofibers can only give a robust response to strong acids. Metal salts can react with hydrogen sulfate to form a metal sulfide precipitate and a strong acid. By combining metal salts and polyaniline nanofibers, detection of hydrogen sulfide can be performed.
Another study decorated polyaniline nanofibers with gold nanoparticles to detect volatile sulfur compounds in expired human breath. These sensors can potentially be used in various breath analyses and also in disease diagnosis for diseases with malodor biomarker gases.
Humidity sensors have also been prepared using polyaniline nanofibers. These sensors were prepared through electrospinning of a N,N-dimethylformamide solution of polyaniline nanofibers, poly(vinyl butyral) (PVB), and poly(ethylene oxide) (PEO). These sensors were shown to have high sensitivity, with resistance changes of three orders of magnitude. Furthermore, the sensors showed good sensing linearity, fast response, small hysterics, and good repeatability. | 0 | Colloidal Chemistry |
The cathodes of lithium-ion batteries are often made of lithiated oxides of cobalt, nickel, or manganese, that can readily and reversibly incorporate lithium ions in their molecular structure. Cobalt oxide nanomaterials, such as nanotubes, offer high surface-to-volume ratio and short path lengths for lithium cation transport, leading to fast charging capabilities. However, capacity, coulombic efficiency, and cycle life may suffer due to excessive formation of SEI. The nanowires may incorporate other substances, for example, diphenylalanine.
Cobalt oxide particles may be anchored on substrates such as graphene to improve the dimensional stability of the anode and to prevent particle aggregation during lithium charge and discharge processes. | 1 | Solid-state chemistry |
In the diffusion method, the radioactive probe is usually diluted in a solvent applied to the sample, dried and it is diffused into the material by tempering it. The solution with the radioactive probe should be as pure as possible, since all other substances can diffuse into the sample and affect thereby the measurement results. The sample should be sufficiently diluted in the sample. Therefore, the diffusion process should be planned so that a uniform distribution or sufficient penetration depth is achieved. | 1 | Solid-state chemistry |
Schmalzried received the Wilhelm Jost Memorial Medal in 1994 and the Bunsen Medal in 2013. He is "External Scientific Member" of the Max Planck Institute for Biophysical Chemistry in Göttingen, member of the Göttingen Academy of Sciences, the Leopoldina, corresponding member of the Austrian Academy of Sciences and member of the Academia Europaea (1989). He was awarded an honorary doctor at the University of Stuttgart in 2003. | 1 | Solid-state chemistry |
Above 500 °C, TaCl disproportionates further releasing TaCl. TaCl is insoluble in room temperature water, or dilute acid, but dissolves in boiling water. A blue-green solution is formed. | 1 | Solid-state chemistry |
Several carbides are assumed to be salts of the acetylide anion (also called percarbide, by analogy with peroxide), which has a triple bond between the two carbon atoms. Alkali metals, alkaline earth metals, and lanthanoid metals form acetylides, for example, sodium carbide NaC, calcium carbide CaC, and LaC. Lanthanides also form carbides (sesquicarbides, see below) with formula MC. Metals from group 11 also tend to form acetylides, such as copper(I) acetylide and silver acetylide. Carbides of the actinide elements, which have stoichiometry MC and MC, are also described as salt-like derivatives of .
The C–C triple bond length ranges from 119.2 pm in CaC (similar to ethyne), to 130.3 pm in LaC and 134 pm in UC. The bonding in LaC has been described in terms of La with the extra electron delocalised into the antibonding orbital on , explaining the metallic conduction. | 1 | Solid-state chemistry |
Chemical vapour deposition is a method widely used for the preparation of coatings and semiconductors from molecular precursors. A carrier gas transports the gaseous precursors to the material for coating. | 1 | Solid-state chemistry |
Synthesis of silver nanoparticles has been investigated utilizing many ubiquitous fungal species including Trichoderma, Fusarium, Penicillium, Rhizoctonia, Pleurotus and Aspergillus. Extracellular synthesis has been demonstrated by Trichoderma virde, T. reesei, Fusarium oxysporm, F. semitectum, F. solani, Aspergillus niger, A. flavus, A. fumigatus, A. clavatus, Pleurotus ostreatus, Cladosporium cladosporioides, Penicillium brevicompactum, P. fellutanum, an endophytic Rhizoctonia sp., Epicoccum nigrum, Chrysosporium tropicum, and Phoma glomerata, while intracellular synthesis was shown to occur in a Verticillium species, and in Neurospora crassa. | 0 | Colloidal Chemistry |
Fréchet’s early work focused on polymer-supported chemistry with the first approach to the solid-phase synthesis of oligosaccharides and pioneering work on polymeric reagents and polymer protecting groups. In 1979 Working with C.G. Willson at IBM during a sabbatical leave, he invented chemically amplified photoresists for micro and nanofabrication. This widely used patented technology which enables the extreme miniaturization of microelectronic devices is now ubiquitous for the fabrication of the very powerful computing and communication equipment in worldwide use. The addition of photogenerated bases led to additional advances in chemically amplified resists. In 1990 working with Craig Hawker at Cornell, he developed the convergent synthesis of dendrimers as well as approaches to hyperbranched polymers. In 1992, working with F. Svec at Cornell, he reported the first preparation of macroporous polymer monoliths that are now used in a variety of chemical separations. Later work at Berkeley saw the development of polymers and dendrimers as carriers for targeted therapeutics and successful approaches to new organic materials for transistors and solar cells. | 1 | Solid-state chemistry |
The Indian Salt Service is part of India's Salt Organization which is headquartered in Jaipur. The service is headed by the Salt Commissioner below whom are five Deputy Salt Commissioners and nine Assistant Salt Commissioners who man the agency with the help of other supporting staff. The Deputy Salt Commissioners head regional offices and the Assistant Salt Commissioners are in charge of divisional offices of the organisation. The Service has four regional offices at Chennai, Mumbai, Ahmedabad and Kolkata and field offices in the salt producing states. | 1 | Solid-state chemistry |
John Stuart Anderson FRS, FAA, (9 January 1908 – 25 December 1990) was a British and Australian scientist who was Professor of Chemistry at the University of Melbourne and Professor of Inorganic Chemistry at the University of Oxford.
He was born in Islington, London, the son of a Scottish cabinet-maker, and attended school in the area but learned most of his chemistry at the Islington Public Library. His tertiary education was at the Northern Polytechnic Institute, Imperial College and the Royal College of Science, all in London.
Anderson's most important research work was:
* on the application of Raman spectroscopy to valence problems
* accounting for the composition ranges of non-stoichiometric compounds by combining the ideas of Schottky and Wagner with those of Fowler and Lacher
* his use of field-emission and field ion microscopy to study surface reactions at the atomic level
*his use of the electron microscope to solve problems of reaction mechanisms in solid state chemistry
* on the conditions of equilibrium of non-stoichiometric chemical compounds.
In addition he carried out practical investigations on the composition of minerals mined in Australia, assisted on one project by Masters candidate Ken McTaggart who went on to be a senior research officer at CSIRO. He developed a love of the Australian bush and, with his family, a lifelong attachment to the country.
Anderson was co-author with Harry Julius Emeléus of the seminal textbook Modern Aspects of Inorganic Chemistry, first published in 1938, which went through numerous editions and translations for over thirty years.
John Stuart Anderson died from cancer in Canberra on Christmas Day, 1990.
In memory of John, the University of Melbourne created the JS Anderson Prize awarded to a promising research student in the area of Chemistry. | 1 | Solid-state chemistry |
Quantum tunnelling is an essential phenomenon for nuclear fusion. The temperature in stellar cores is generally insufficient to allow atomic nuclei to overcome the Coulomb barrier and achieve thermonuclear fusion. Quantum tunnelling increases the probability of penetrating this barrier. Though this probability is still low, the extremely large number of nuclei in the core of a star is sufficient to sustain a steady fusion reaction. | 1 | Solid-state chemistry |
Brine consists of concentrated solution of Na and Cl ions. Sodium chloride per se does not exist in water: it is fully ionized. Other cations found in various brines include K, Mg, Ca, and Sr. The latter three are problematic because they form scale and they react with soaps. Aside from chloride, brines sometimes contain Br and I and, most problematically, . Purification steps often include the addition of calcium oxide to precipitate solid magnesium hydroxide together with gypsum (CaSO), which can be removed by filtration. Further purification is achieved by fractional crystallization. The resulting purified salt is called evaporated salt or vacuum salt. | 1 | Solid-state chemistry |
Akin to the preparation of most xanthates, sodium ethyl xanthate can be prepared by treating sodium ethoxide with carbon disulfide: | 1 | Solid-state chemistry |
Titanium(III) oxide is the inorganic compound with the formula TiO. A black semiconducting solid, it is prepared by reducing titanium dioxide with titanium metal at 1600 °C.
TiO adopts the AlO (corundum) structure. It is reactive with oxidising agents. At around 200 °C, there is a transition from semiconducting to metallic conducting. Titanium(III) oxide occurs naturally as the extremely rare mineral in the form of tistarite.
Other titanium(III) oxides include LiTiO and LiTiO. | 1 | Solid-state chemistry |
Cellular composites extend stretch-dominated lattices to the ultralight regime (below ten milligrams per cubic centimeter). Performance depends positively on the framework rigidity of the lattice, node connectivity, slenderness of strut members and the scaling of the density cost of mechanical connections.
Conventional fiber composites make truss cores and structural frames, with bonded assembly of substructures or continuous fiber winding. Examples of such truss cores have been reported with continuous two-dimensional (2D) geometric symmetry and nearly ideal but highly anisotropic specific modulus scaling.
Three-dimensional open-cell lattice materials occur in natural and engineered systems, spanning many length scales. Their mechanical properties scale with relative density according to the geometry. They display either stretch-dominated or transverse beam bending-dominated microstructural behavior, based on periodic mechanical models. For Young’s modulus E, ideal stretch-dominated scaling with density ρ follows a proportional law E∝ρ, while common stochastic foams follow a quadratic law E∝ρ2 otherwise associated with transverse beam bending-dominated behavior. At ultralight densities a further reduced cubic scaling law E∝ρ3 is common, such as with aerogels and aerogel composites.
The dependence of scaling on geometry is seen in periodic lattice-based materials that have nearly ideal E∝ρ scaling, with high node connectedness relative to stochastic foams. These structures have previously been implemented only in relatively dense engineered materials. For the ultralight regime the E∝ρ2 scaling seen in denser stochastic cellular materials applies to electroplated tubular nickel micro-lattices, as well as carbon-based open-cell stochastic foams, including carbon microtube aerographite and graphene cork. | 0 | Colloidal Chemistry |
Copper(II) oxide belongs to the monoclinic crystal system. The copper atom is coordinated by 4 oxygen atoms in an approximately square planar configuration.
The work function of bulk CuO is 5.3 eV | 1 | Solid-state chemistry |
George William Scott Blair (23 July 1902 – 30 September 1987) was British chemist noted for his contributions to rheology. In fact he has been called "the first rheologist" | 0 | Colloidal Chemistry |
Hybrid metal foams typically have a thin film on the underlying porous substrate. Coating metal foams with a different material has been shown to improve the mechanical properties of the metal foam, especially because they are prone to bending deformation mechanisms due to their cellular structure. The addition of a thin film can also improve other properties such as corrosion resistance and enable surface functionalization for catalytic flow processes.
To fabricate hybrid metal foams, thin films are deposited onto a foam substrate with electrodeposition at room temperature. A two-electrode cell setup in a Watt's bath can be used. Recent studies have demonstrated issues with the uniformity of the thin-film due to the complex geometry of metal foams. Issues with uniformity have been addressed in more recent studies through the implementation of nanoparticle thin films, leading to improved mechanical and corrosion resistance properties.
Recent studies on hybrid foams have also been used to address non-renewable energy resources. Transition metal hybrid foams have previously been fabricated through a combination of electrodeposition and hydrogen bubbling processes to enhance the diffusivity of fluids through the porous material and improve the electrical properties for enhanced charge transfer. Thus, such foams can be used to make electrocatalytic water splitting processes more efficient.
Hybrid metal foams may have favorable conductive properties for flexible devices. Through the application of a thin layer of metal onto a porous polymer substrate via gas-phase deposition, researchers have been able to achieve high conductivity while maintaining the flexibility of the polymer matrix. Through cycling testing, it has been shown that hybrid foams are capable of surface deformation sensing. Future efforts seek to characterize the change in cross-linking and porosity of materials as deposition occurs. Additionally, the interaction or compatibility between different polymers and metals in foam ligands can be explored in order to get an improved understanding of their sensitivity to external forces. This would help improve resistance to compressive forces. | 0 | Colloidal Chemistry |
From 2007 to 2015, Wu worked as a scientist in the NIST Center for Neutron Research and for the department of materials science and engineering at University of Maryland, College Park. In 2015, she was promoted to senior scientist at NIST. | 1 | Solid-state chemistry |
Researchers have invented a nanofluid-based ultrasensitive optical sensor that changes its colour on exposure to extremely low concentrations of toxic cations. The sensor is useful in detecting minute traces of cations in industrial and environmental samples. Existing techniques for monitoring cations levels in industrial and environmental samples are expensive, complex and time-consuming. The sensor is designed with a magnetic nanofluid that consists of nano-droplets with magnetic grains suspended in water. At a fixed magnetic field, a light source illuminates the nanofluid where the colour of the nanofluid changes depending on the cation concentration. This color change occurs within a second after exposure to cations, much faster than other existing cation sensing methods.
Such response stimulus nanofluids are also used to detect and image defects in ferromagnetic components. The photonic eye, as it has been called, is based on a magnetically polarizable nano-emulsion that changes colour when it comes into contact with a defective region in a sample. The device might be used to monitor structures such as rail tracks and pipelines. | 0 | Colloidal Chemistry |
Dipankar Das Sarma, popularly known as D.D. Sarma, is an Indian scientist and structural chemist, known for his researches in the fields of Solid State Chemistry, Spectroscopy, Condensed Matter Physics, Materials Science, and Nanoscience. He is a former MLS Chair Professor of Physics and Chairman of the Centre for Advanced Materials and the GAST Professor of Uppsala University, Sweden, A recipient of TWAS Physics Prize and the UNESCO Biennial Javed Husain Prize, Sarma was honored by the Council for Scientific and Industrial Research (CSIR), Government of India, in 1994, with the Shanti Swarup Bhatnagar Prize for Science and Technology. | 1 | Solid-state chemistry |
DATEM (diacetyl tartaric acid ester of mono- and diglycerides, also E472e) is an emulsifier primarily used in baking to strengthen the gluten network in dough. It is added to crusty breads, such as rye, to impart a springy, chewy texture. It is also used in the production of biscuits, coffee whiteners, salsa con queso, ice cream, and salad dressings. | 0 | Colloidal Chemistry |
A commercial graphitic carbon nitride is available under the brand name Nicanite. In its micron-sized graphitic form, it can be used for tribological coatings, biocompatible medical coatings, chemically inert coatings, insulators and for energy storage solutions. Graphitic carbon nitride is reported as one of the best hydrogen storage materials. It can also be used as a support for catalytic nanoparticles. | 1 | Solid-state chemistry |
Amorphous indium oxide is insoluble in water but soluble in acids, whereas crystalline indium oxide is insoluble in both water and acids. The crystalline form exists in two phases, the cubic (bixbyite type) and rhombohedral (corundum type). Both phases have a band gap of about 3 eV. The parameters of the cubic phase are listed in the infobox.
The rhombohedral phase is produced at high temperatures and pressures or when using non-equilibrium growth methods. It has a space group Rc No. 167, Pearson symbol hR30, a = 0.5487 nm, b = 0.5487 nm, c = 1.4510 nm, Z = 6 and calculated density 7.31 g/cm. | 1 | Solid-state chemistry |
The Saltcellar with Portuguese Figures is a salt cellar in carved ivory, made in the Kingdom of Benin in West Africa in the 16th century, for the European market. It is attributed to an unknown master or workshop who has been given the name Master of the Heraldic Ship by art historians. It depicts four Portuguese figures, two of higher class and the other two are possibly guards protecting them. In the 16th century, Portuguese visitors ordered ivory salt cellars and ivory spoons similar to this object. This Afro-Portuguese ivory salt cellar was carved in the style of a Benin court ivory, comparable to the famous Benin bronzes and Benin ivory masks.
These kinds of ivory arts were commissioned and exported initially from Sierra Leone and later Benin City, Nigeria. During the age of exploration European powers expanded their trade and efforts towards establishing trade posts in the New World, Africa, the Middle East and Asia. Portuguese sailors disembarked from their caravels to buy goods for trading like ivory, gold, and others. These goods were taken from markets to colonial outposts to Portugal and then traded within European markets. During the 16th and 17th century countries that participated in colonialism reaped the economical benefits from its international trade.
The salt cellar was probably carved for a Portuguese nobleman to put it on his dining table. It is one of four almost identical pieces, probably made as a set. The other three are now in European museums. Ivory salt cellars and ivory spoons like the Sapi-Portuguese Ivory Spoon, also in the Metropolitan Museum of Art, were common pieces of art that Portuguese sailors brought back from West African countries. There are no records of the order for this commission but it is believed that a Benin Ivory carver produced this in the Benin Kingdom, in modern day Nigeria. | 1 | Solid-state chemistry |
;1-series / B890000 series :
* B893000, B164903 - Twin 3-input AND gates (orange) ("2.3A1", "2x3N1")
* B893001, B164904 - Twin 2-input AND gates (orange) ("2.2A1", "2x2N1")
* B893002, 2P72729 - Twin 3-input OR gates (orange) ("2.3O1", "23O1", "2x3P1")
* B893003, 2P72730 - Twin 2-input OR gates (orange) ("2.2O1", "22O1", "2x2P1")
* B894002, B164910 - Twin inverter amplifier (yellow) ("2IA1", "2.IA1", "2xIA1")
* B894005, 2P72728 - Twin inverter amplifier (yellow) ("2IA2", "2xIA2")
* B894001, B164909 - Twin emitter follower (yellow) ("2EF1", 2xEF1")
* B894003, 2P72727 - Twin emitter follower (yellow) ("2EF2", "2xEF2")
* B894000, B164907 - Emitter follower/inverter amplifier (yellow) ("EF1/IA1")
* B895000, B164901 - Pulse shaper (Schmitt trigger + amplifier) (green) ("PS1")
* B895001, B164908 - One-shot multivibrator ("OS1")
* B895003 - One-shot multivibrator ("OS2")
* B892000, B164902 - Flip-flop (red) ("FF1")
* B892001, 2P72707 - Shift-register Flip-flop (red) ("FF2")
* B892002 - Flip-flop (red) ("FF3")
* B892003 - Flip-flop (red) ("FF4")
* B893004, 2P72726 - Pulse logic (orange) ("PL1", "2xPL1")
* B893007 - Pulse logic (orange) ("2xPL2")
* B885000, B164911 - Decade counter ("DC1")
* B890000 - Power amplifier ("PA1")
* B896000 - Twin selector switch for core memories ("2SS1")
* B893005 - Selection gate for core memories ("SG1")
* 2P72732 - Pulse generator for core memories ("PG1")
* 2P72731 - Read amplifier for core memories ("RA1")
;10-series:
* 2P73701 - Flip-flop ("FF10")
* 2P73702 - Flip-flop ("FF11")
* 2P73703 - Flip-flop / Bistable multivibrator with built-in trigger gates and set-reset inputs (black) ("FF12")
* Dual trigger gate ("2.TG13")
* Dual trigger gate ("2.TG14")
* Quadruple trigger gate ("4.TG15")
* Dual positive gate inverter amplifier ("2.GI10")
* Dual positive gate inverter amplifier ("2.GI11")
* Dual positive gate inverter amplifier ("2.GI12")
* Gate amplifier ("GA11")
* One-shot multivibrator ("OS11")
* Timer unit ("TU10")
* Pulse driver ("PD11")
* Relay driver ("RD10")
* Relay driver ("RD11")
* Power amplifier ("PA10")
* Pulse shaper ("PS10")
* Numerical indicator tube driver ("ID10")
;20-series:
* 2P73710 - ("2.GI12", "2GI12") | 1 | Solid-state chemistry |
* ~40% dipalmitoylphosphatidylcholine (DPPC);
* ~40% other phospholipids (PC);
* ~10% surfactant proteins (SP-A, SP-B, SP-C and SP-D);
* ~10% neutral lipids (Cholesterol);
* Traces of other substances. | 0 | Colloidal Chemistry |
The main exposure to UFPs is through inhalation. Owing to their size, UFPs are considered to be respirable particles. Contrary to the behaviour of inhaled PM and PM, ultrafine particles are deposited in the lungs, where they have the ability to penetrate tissue and undergo interstitialization, or to be absorbed directly into the bloodstream—and therefore are not easily removed from the body and may have immediate effect. Exposure to UFPs, even if components are not very toxic, may cause oxidative stress, inflammatory mediator release, and could induce heart disease, lung disease, and other systemic effects.
The exact mechanism through which UFP exposure leads to health effects remains to be elucidated, but effects on Blood pressure may play a role. It has recently been reported that UFP is associated with an increase in blood pressure in schoolchildren with the smallest particles inducing the largest effect. According to research, infants whose mothers were exposed to higher levels of UFPs during pregnancy are much more likely to develop asthma.
There is a range of potential human exposures that include occupational, due to the direct manufacturing process or a byproduct from an industrial or office environment, as well as incidental, from contaminated outdoor air and other byproduct emissions. In order to quantify exposure and risk, both in vivo and in vitro studies of various UFP species are currently being done using a variety of animal models including mouse, rat, and fish. These studies aim to establish toxicological profiles necessary for risk assessment, risk management, and potential regulation and legislation.
Some sizes of UFPs may be filtered from the air using ULPA filters. | 0 | Colloidal Chemistry |
Ammonium perfluorononanoate (APFN) is an anionic surfactant that in water forms liquid crystalline phases (Lyotropic liquid crystal). It is the ammonium salt of perfluorononanoic acid.
The phase diagram of APFN/HO system is delineated by the presence of a lamellar phase and a nematic phase with awide isotropic solution. The nematic phase is of the type I, and the aggregates have a positive and diamagnetic anisotropy. In the presence of a magnetic field, the aggregates align parallel to the field direction. The change of phase at the lamellar-nematic temperature has been ascribed to order-disorder transitions. | 0 | Colloidal Chemistry |
The mineral pyrite ( ), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula FeS (iron (II) disulfide). Pyrite is the most abundant sulfide mineral.
Pyrites metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of fools gold. The color has also led to the nicknames brass, brazzle, and brazil, primarily used to refer to pyrite found in coal.
The name pyrite is derived from the Greek (), stone or mineral which strikes fire, in turn from (), fire. In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what is now called pyrite.
By Georgius Agricola's time, , the term had become a generic term for all of the sulfide minerals.
Pyrite is usually found associated with other sulfides or oxides in quartz veins, sedimentary rock, and metamorphic rock, as well as in coal beds and as a replacement mineral in fossils, but has also been identified in the sclerites of scaly-foot gastropods. Despite being nicknamed "fool's gold", pyrite is sometimes found in association with small quantities of gold. A substantial proportion of the gold is "invisible gold" incorporated into the pyrite (see Carlin-type gold deposit). It has been suggested that the presence of both gold and arsenic is a case of coupled substitution but as of 1997 the chemical state of the gold remained controversial. | 1 | Solid-state chemistry |
Equilibrium phase transitions (e.g. order/disorder), an equation of state, and the kinetics of colloidal crystallization have all been actively studied, leading to the development of several methods to control the self-assembly of the colloidal particles. Examples include colloidal epitaxy and space-based reduced-gravity techniques, as well as the use of temperature gradients to define a density gradient. This is somewhat counterintuitive as temperature does not play a role in determining the hard-sphere phase diagram. However, hard-sphere single crystals (size 3 mm) have been obtained from a sample in a concentration regime that would remain in the liquid state in the absence of a temperature gradient. | 0 | Colloidal Chemistry |
For most fluids and some homogenous solid materials, like gels, diffusion is the same in all directions and characterized by the same diffusion coefficient number. This property is called isotropicity which gives cubosomes the ability to be used in biological tissues which are highly structured and typically have different diffusion coefficients along different directions (anisotropic). Because of advantages such as the unique structure of the cubic phase and its resemblance to biological membranes as well as biodegradability of lipids, cubosomes are a great tool for drug delivery system. In addition, the bicontinuous cubic liquid crystalline phase (cubic phase)’s tortuosity is useful for slowing down diffusion as shown by Higuchi’s square root of time release kinetics. Capability to encapsulate hydrophilic, hydrophobic, and amphiphilic substance, being simple to prepare, and all the aforementioned qualities give cubosomes a property that can be used in controlled transport applications as drug delivery vehicles. | 0 | Colloidal Chemistry |
Rupp received a Master of Natural Science Degree at the University of Vienna followed by a doctoral degree at ETH Zurich. Her undergraduate efforts were recognised by the Austrian Chemical Society, who presented her with their prize for her diploma thesis. She was awarded the ETH Zurich medal for PhD excellence for her thesis on micro-Solid Oxide Fuel Cells and functional ceramic materials under the supervision of Ludwig Gauckler at ETH Zurich. | 1 | Solid-state chemistry |
In addition to the carbides, other groups of related carbon compounds exist:
*graphite intercalation compounds
*alkali metal fullerides
*endohedral fullerenes, where the metal atom is encapsulated within a fullerene molecule
*metallacarbohedrenes (met-cars) which are cluster compounds containing C units.
*tunable nanoporous carbon, where gas chlorination of metallic carbides removes metal molecules to form a highly porous, near-pure carbon material capable of high-density energy storage.
*transition metal carbene complexes.
* two-dimensional transition metal carbides: MXenes | 1 | Solid-state chemistry |
Cooperative PJTE in BaTiO-type crystals and ferroelectricity. In crystals with PJTE centers the interaction between the local distortions may lead to their ordering to produce a phase transition to a regular crystal phase with lower symmetry. Such cooperative PJTE is quite similar to the cooperative JTE; it was shown in one of the first studies of the PJTE in solid state systems that in the case of ABO crystals with perovskite structure the local dipolar PJTE distortions at the transition metal B center and their cooperative interactions lead to ferroelectric phase transitions. Provided the criterion for PJTE is met, each [BO] center has an APES with eight equivalent minima along the trigonal axes, six orthorhombic, and (higher) twelve tetragonal saddle-points between them. With temperature, the gradually reached transitions between the minima via the different kind of saddle-points explains the origin of all the four phases (three ferroelectric and one paraelectric) in perovskites of the type BaTiO and their properties. The predicted by the theory trigonal displacement of the Ti ion in all four phases, the fully disordered PJTE distortions in the paraelectric phase, and their partially disordered state in two other phases was confirmed by a variety of experimental investigations (see in ).
Multiferroicity and magnetic-ferroelectric crossover. The PJTE theory of ferroelectricity in ABO3 crystals was expanded to show that, depending on the number of electrons in the d shell of the transition metal ion B and their low spin or high spin arrangement (which controls the symmetry and spin multiplicity of the ground and PJTE active excited states of the [BO] center), the ferroelectricity may coexist with a magnetic moment (multiferroicity). Moreover, in combination with the temperature dependent spin crossover phenomenon (which changes the spin multiplicity), this kind of multiferroicity may lead to a novel effect known as a magnetic-ferroelectric crossover.
Solid state magnetic-dielectric bistability. Similar to the above-mentioned molecular bistability induced by the hidden PJTE, a magnetic-dielectric bistability due to two coexisting equilibrium configurations with corresponding properties may take place also in crystals with transition metal centers, subject to the electronic configuration with half-filled e or t shells. As in molecular systems, the latter produce a hidden PJTE and local bistability which, distinguished from the molecular case, are enhanced by the cooperative interactions, thus acquiring larger lifetimes. This crystal bistability was proved by calculations for LiCuO and NaCuO crystals, in which the Cu ion has the electronic e(d) configuration (similar to the CuF molecule).
Giant enhancement of observable properties in interaction with external perturbations. In a recent development it was shown that in inorganic crystals with PJTE centers, in which the local distortions are not ordered (before the phase transition to the cooperative phase), the effect of interaction with external perturbations contains an orientational contribution which enhances the observable properties by several orders of magnitude. This was demonstrated on the properties of crystals like paraelectric BaTiO in interaction with electric fields (in permittivity and electrostriction), or under a strain gradient (flexoelectricity). These giant enhancement effects occur due to the dynamic nature of the PJTE local dipolar distortions (their tunneling between the equivalent minima); the independently rotating dipole moments on each center become oriented (frozen) along the external perturbation resulting in an orientational polarization which is not there in the absence of the PJTE | 1 | Solid-state chemistry |
At the start, electrodes were made mainly from wires or metal sheets.
Nowadays, the electric field in DEP is created by means of electrodes which minimize the magnitude of the voltage needed. This has been possible using fabrication techniques such as photolithography, laser ablation and electron beam patterning.
These small electrodes allow the handling of small bioparticles.
The most used electrode geometries are isometric, polynomial, interdigitated, and crossbar. Isometric geometry is effective for particle manipulation with DEP but repelled particles do not collect in well defined areas and so separation into two homogeneous groups is difficult. Polynomial is a new geometry producing well defined differences in regions of high and low forces and so particles could be collected by positive and negative DEP. This electrode geometry showed that the electrical field was highest at the middle of the inter-electrode gaps. Interdigitated geometry comprises alternating electrode fingers of opposing polarities and is mainly used for dielectrophoretic trapping and analysis. Crossbar geometry is potentially useful for networks of interconnects. | 0 | Colloidal Chemistry |
Titanium foams exhibit high specific strength, high energy absorption, excellent corrosion resistance and biocompatibility. These materials are ideally suited for applications within the aerospace industry. An inherent resistance to corrosion allows the foam to be a desirable candidate for various filtering applications. Further, titanium's physiological inertness makes its porous form a promising candidate for biomedical implantation devices. The largest advantage in fabricating titanium foams is that the mechanical and functional properties can be adjusted through manufacturing manipulations that vary porosity and cell morphology. The high appeal of titanium foams is directly correlated to a multi-industry demand for advancement in this technology. | 0 | Colloidal Chemistry |
Nazar's patents include;
* 2002 New electrode materials for a rechargeable electrochemical cell
* 2007 Mixed Lithium/Sodium Ion Iron Fluorophosphate Cathodes for Lithium Ion Batteries
* 2009 Sulfur-carbon material
* 2011 Multicomponent electrodes for rechargeable batteries
* 2014 Composites comprising mxenes for cathodes of lithium sulphur cells
* 2015 Electrode materials for rechargeable zinc cells and batteries produced therefrom | 1 | Solid-state chemistry |
The colour of an ionic compound is often different from the colour of an aqueous solution containing the constituent ions, or the hydrated form of the same compound.
The anions in compounds with bonds with the most ionic character tend to be colorless (with an absorption band in the ultraviolet part of the spectrum). In compounds with less ionic character, their color deepens through yellow, orange, red, and black (as the absorption band shifts to longer wavelengths into the visible spectrum).
The absorption band of simple cations shifts toward a shorter wavelength when they are involved in more covalent interactions. This occurs during hydration of metal ions, so colorless anhydrous ionic compounds with an anion absorbing in the infrared can become colorful in solution.
Salts exist in many different colors, which arise either from their constituent anions, cations or solvates. For example:
* sodium chromate is made yellow by the chromate ion .
* potassium dichromate is made red-orange by the dichromate ion .
* cobalt(II) nitrate hexahydrate is made red by the chromophore of hydrated cobalt(II) .
* copper(II) sulfate pentahydrate is made blue by the hydrated copper(II) cation.
* potassium permanganate is made violet by the permanganate anion .
* nickel(II) chloride hexahydrate is made green by the hydrated nickel(II) chloride .
* sodium chloride NaCl and magnesium sulfate heptahydrate are colorless or white because the constituent cations and anions do not absorb light in the part of the spectrum that is visible to humans.
Some minerals are salts, some of which are soluble in water. Similarly, inorganic pigments tend not to be salts, because insolubility is required for fastness. Some organic dyes are salts, but they are virtually insoluble in water. | 1 | Solid-state chemistry |
For 16 years Sadoway taught 3.091 Introduction to Solid State Chemistry at MIT, one of the largest classes at MIT. Sadoway's animated teaching style was popular with students and freshman enrollment in the course steadily increased through 2010.
In the fall of 2007, the number of students registering for 3.091 reached 570 students, over half the freshman class. The largest lecture hall available on campus seats 566 students. Sadoway much preferred teaching in one of the smaller lecture halls, seating only 450; as such, the institute had to take the unprecedented step of streaming digital video of the lecture into an overflow room to accommodate all the students interested in taking the course. In contrast, most classes at MIT are relatively small with approximately 60% of classes at MIT having fewer than 20 students. The popularity of this course has reached outside of the MIT campus as a result of the MIT OpenCourseWare initiative. This is seen in a comment by Bill Gates who told the Seattle Post-Intelligencer "Everybody should watch chemistry lectures -- they're far better than you think. Don Sadoway, MIT -- best chemistry lessons anywhere. Unbelievable".
Sadoways lectures often included the history of science, especially with respect to the Nobel Prize. Sadoway gave out "library assignments" in which he asked students to research Nobel Prize–winning papers. He began his lectures by playing music, which has some connection with the lectures material. For example, for the lecture on hydrogen bonding he plays Handels Water Music. For one of the lectures on polymers he plays Aretha Franklins "Chain of Fools". He ended his lectures with five minutes on the topic of "chemistry and the world around us". Examples include automotive exhaust catalytic converters (technology), forensic examination of paintings (chemistry in the fine arts), the mistreatment of Rosalind Franklin in the quest to discover the structure of DNA (intellectual dishonesty), the metallurgical failure that sank the Titanic (greed and incompetence), and the clarification of champagne (viticulture). | 1 | Solid-state chemistry |
For the magnetic dipole interaction, the frequency of the precession of the nuclear spin around the axis of the magnetic field is given by:
is the Landé g-factor und is the nuclear magneton.
With follows:
From the general theory we get:
For the magnetic interaction follows: | 1 | Solid-state chemistry |
Her awards and honors include:
* 2003 American Crystallographic Association Margaret C. Etter Early Career Award
* 2004 Alfred P. Sloan Research Fellowship
* 2006 Baylor Alumni Association Outstanding Young Alum
* 2008 Iota Sigma Pi Agnes Fay Morgan Research Award
* 2016 University of Texas at Dallas Women Leading in Diversity Honouree
* 2019 American Chemical Society Wilfred T. Doherty Award for Excellence in Chemistry
* 2019 Elected Fellow of the American Association for the Advancement of Science | 1 | Solid-state chemistry |
Prior to the realisation of the harmfulness of radiation, uranium was included in false teeth and dentures, as its slight fluorescence made the dentures appear more like real teeth in a variety of lighting conditions.
Depleted UO (DUO) can be used as a material for radiation shielding. For example, DUCRETE is a "heavy concrete" material where gravel is replaced with uranium dioxide aggregate; this material is investigated for use for casks for radioactive waste. Casks can be also made of DUO-steel cermet, a composite material made of an aggregate of uranium dioxide serving as radiation shielding, graphite and/or silicon carbide serving as neutron radiation absorber and moderator, and steel as the matrix, whose high thermal conductivity allows easy removal of decay heat.
Depleted uranium dioxide can be also used as a catalyst, e.g. for degradation of volatile organic compounds in gaseous phase, oxidation of methane to methanol, and removal of sulfur from petroleum. It has high efficiency and long-term stability when used to destroy VOCs when compared with some of the commercial catalysts, such as precious metals, TiO, and CoO catalysts. Much research is being done in this area, DU being favoured for the uranium component due to its low radioactivity.
The use of uranium dioxide as a material for rechargeable batteries is being investigated. The batteries could have high power density and potential of 4.7 V per cell. Another investigated application is in photoelectrochemical cells for solar-assisted hydrogen production where UO is used as a photoanode. In earlier times, uranium dioxide was also used as heat conductor for current limitation (URDOX-resistor), which was the first use of its semiconductor properties.
Uranium dioxide displays strong piezomagnetism in the antiferromagnetic state, observed at cryogenic temperatures below 30 kelvins. Accordingly, the linear magnetostriction found in UO changes sign with the applied magnetic field and exhibits magnetoelastic memory switching phenomena at record high switch-fields of 180,000 Oe. The microscopic origin of the material magnetic properties lays in the face-centered-cubic crystal lattice symmetry of uranium atoms, and its response to applied magnetic fields. | 1 | Solid-state chemistry |
Miniemulsions have wide application in the synthesis of nanomaterials and in the pharmaceutical and food industries. For example, miniemulsion-based processes are, therefore, particularly adapted for the generation of nanomaterials. There is a fundamental difference between traditional emulsion polymerisation and a miniemulsion polymerisation. Particle formation in the former is a mixture of micellar and homogeneous nucleation, particles formed via miniemulsion however are mainly formed by droplet nucleation. In the pharmaceutical industry, oil droplets act as tiny containers that carry water-insoluble drugs, and the water provides a mild environment that is compatible with the human body. Moreover, nanoemulsions that carry drugs allow the drugs to crystallize in a controlled size with a good dissolution rate. Finally, in the food industry, miniemulsions can not only be loaded with water-insoluble nutrients, such as beta-carotene and curcumin, but also improve the nutrients' digestibility. Miniemulsions are also used in the creation of cannabinoid infused beverages and foods. Emulsifying cannabiniods has shown to increase bioavailability and digestion time. | 0 | Colloidal Chemistry |
The origins of colloidal crystals go back to the mechanical properties of bentonite sols, and the optical properties of Schiller layers in iron oxide sols. The properties are supposed to be due to the ordering of monodisperse inorganic particles. Monodisperse colloids, capable of forming long-range ordered arrays, existing in nature. The discovery by W.M. Stanley of the crystalline forms of the tobacco and tomato viruses provided examples of this. Using X-ray diffraction methods, it was subsequently determined that when concentrated by centrifuging from dilute water suspensions, these virus particles often organized themselves into highly ordered arrays.
Rod-shaped particles in the tobacco mosaic virus could form a two-dimensional triangular lattice, while a body-centered cubic structure was formed from the almost spherical particles in the tomato Bushy Stunt Virus. In 1957, a letter describing the discovery of "A Crystallizable Insect Virus" was published in the journal Nature. Known as the Tipula Iridescent Virus, from both square and triangular arrays occurring on crystal faces, the authors deduced the face-centered cubic close-packing of virus particles. This type of ordered array has also been observed in cell suspensions, where the symmetry is well adapted to the mode of reproduction of the organism. The limited content of genetic material places a restriction on the size of the protein to be coded by it. The use of a large number of the same proteins to build a protective shell is consistent with the limited length of RNA or DNA content.
It has been known for many years that, due to repulsive Coulombic interactions, electrically charged macromolecules in an aqueous environment can exhibit long-range crystal-like correlations with interparticle separation distances often being considerably greater than the individual particle diameter. In all of the cases in nature, the same iridescence is caused by the diffraction and constructive interference of visible lightwaves which falls under Bragg’s law.
Because of the rarity and pathological properties, neither opal nor any of the organic viruses have been very popular in scientific laboratories. The number of experiments exploring the physics and chemistry of these “colloidal crystals” has emerged as a result of the simple methods which have evolved in 20 years for preparing synthetic monodisperse colloids, both polymer and mineral, and, through various mechanisms, implementing and preserving their long-range order formation. | 0 | Colloidal Chemistry |
Wilhelm Karl Klemm (5 January 1896 – 24 October 1985) was an inorganic and physical chemist.
Klemm did extensive work on intermetallic compounds, rare earth metals, transition elements and compounds involving oxygen and fluorine.
He and Heinrich Bommer were the first to isolate elemental erbium (1934) and ytterbium (1936).
Klemm refined Eduard Zintl's ideas about the structure of intermetallic compounds and their connections to develop the Zintl-Klemm concept.
Klemm co-authored one of the ten most-cited papers in the history of the journal Zeitschrift für anorganische und allgemeine Chemie.
His textbooks on inorganic chemistry became standard works for chemists. His Magnetochemie (c1936) is considered foundational to magnetochemistry. Anorganische Chemie (Inorganic Chemistry) by Klemm and Rudolf Hoppe has been described as a legendary work by two titans of solid state chemistry.
Klemm was the second President of the Gesellschaft Deutscher Chemiker (GDCh), serving from 1952 to 1953.
He was President of the International Union of Pure and Applied Chemistry (IUPAC) from 1965 to 1967. Klemm co-edited the journal Zeitschrift für anorganische und allgemeine Chemie from 1939 to 1965.
Since 1985, the GDCh has awarded the Wilhelm Klemm Prize in his honor. | 1 | Solid-state chemistry |
Foam metal has been used in experimental animal prosthetics. In this application, a hole is drilled into the bone and the metal foam inserted, letting the bone grow into the metal for a permanent junction. For orthopedic applications, tantalum or titanium foams are common for their tensile strength, corrosion resistance and biocompatibility.
The back legs of a Siberian Husky named Triumph received foam metal prostheses. Mammalian studies showed that porous metals, such as titanium foam, may allow vascularization within the porous area.
Orthopedic device manufacturers use foam construction or metal foam coatings to achieve desired levels of osseointegration. | 0 | Colloidal Chemistry |
In 2021 California banned PFASs for use in food packaging and from infant and children's products and also required PFAS cookware in the state to carry a warning label. | 0 | Colloidal Chemistry |
Subsets and Splits