This invention is a process for improving the production levels of recombinant proteins or peptides or improving the level of active recombinant proteins or peptides expressed in host cells. The invention is a process of comparing two genetic profiles of a cell that expresses a recombinant protein and modifying the cell to change the expression of a gene product that is upregulated in response to the recombinant protein expression. The process can improve protein production or can improve protein quality, for example, by increasing solubility of a recombinant protein.

More than 155 recombinantly produced proteins and peptides have been approved by the U.S. Food and Drug Administration (FDA) for use as biotechnology drugs and vaccines, with another 370 in clinical trials. Unlike small molecule therapeutics that are produced through chemical synthesis, proteins and peptides are most efficiently produced in living cells. In many cases, the cell or organism has been genetically modified to produce or increase the production of the protein.
When a cell is modified to produce large quantities of a target protein, the cell is placed under stress and often reacts by inducing or suppressing other proteins. The stress that a host cell undergoes during production of recombinant proteins can increase expression of, for example, specific proteins or cofactors to cause degradation of the overexpressed recombinant protein. The increased expression of compensatory proteins can be counterproductive to the goal of expressing high levels of active, full-length recombinant protein. Decreased expression or lack of adequate expression of other proteins can cause misfolding and aggregation of the recombinant protein. While it is known that a cell under stress will change its profile of protein expression, it is not known in any given example which specific proteins will be upregulated or downregulated.
Microarrays
Microarray technology can be used to identify the presence and level of expression of a large number of polynucleotides in a single assay. See for eg. U.S. Pat. No. 6,040,138, filed Sep. 15, 1995, U.S. Pat. No. 6,344,316, filed Jun. 25, 1997, U.S. Pat. No. 6,261,776, filed Apr. 15, 1999, U.S. Pat. No. 6,403,957, filed Oct. 16, 2000, U.S. Pat. No. 6,451,536, filed Sep. 27, 2000, U.S. Pat. No. 6,532,462, filed Aug. 27, 2001, U.S. Pat. No. 6,551,784, filed May 9, 2001, U.S. Pat. No. 6,420,108, filed Feb. 9, 1998, U.S. Pat. No. 6,410,229, filed Dec. 14, 1998, U.S. Pat. No. 6,576,424, filed Jan. 25, 2001, U.S. Pat. No. 6,687,692, filed Nov. 2, 2000, U.S. Pat. No. 6,600,031, filed Apr. 21, 1998, and U.S. Pat. No. 6,567,540, filed Apr. 16, 2001, all assigned to Affymetrix, Inc.
U.S. Pat. No. 6,607,885 to E. I. duPont de Nemours and Co. describes methods to profile and identify gene expression changes after subjecting a bacterial cell to expression altering conditions by comparing a first and second microarray measurement.
Wei et al. used a microarray analysis to investigate gene expression profiles of E. coli with lac gene induction (Wei Y., et al. (2001) High-density microarray-mediated gene expression profiling of Escherichia coli. J Bacteriol. 183(2):545-56). Other groups have also investigated transcriptional profiles regulated after mutation of endogenous genes or deletion of regulatory genes (Sabina, J. et al (2003) Interfering with Different Steps of Protein Synthesis Explored by Transcriptional Profiling of Escherichia coli K-12 J Bacteriol. 185:6158-6170; Lee J H (2003) Global analyses of transcriptomes and proteomes of a parent strain and an L-threonine-overproducing mutant strain. J Bacteriol. 185(18):5442-51; Kabir M M, et al. (2003) Gene expression patterns for metabolic pathway in pgi knockout Escherichia coli with and without phb genes based on RT-PCR J Biotechnol. 105(1-2): 11-31; Eymann C., et al. (2002) Bacillus subtilis functional genomics: global characterization of the stringent response by proteome and transcriptome analysis. J Bacteriol. 184(9):2500-20).
Gill et al. disclose the use of microarray technology to identify changes in the expression of stress related genes in E. coli after expression of recombinant chloramphenicol acetyltransferase fusion proteins (Gill et al. (2001) Genomic Analysis of High-Cell-Density Recombinant Escherichia coli Fermentation and "Cell Conditioning" for Improved Recombinant Protein Yield Biotech. Bioengin. 72:85-95). The stress gene transcription profile, comprising only 16% of the total genome, at high cell density was used to evaluate "cell conditioning" strategies to alter the levels of chaperones, proteases, and other intracellular proteins prior to recombinant protein overexpression. The strategies for "conditioning" involved pharmacological manipulation of the cells, including through dithiothreitol and ethanol treatments.
Asai et al. described the use of microarray analysis to identify target genes activated by over-expression of certain sigma factors that are typically induced after cell stresses (Asai K., et al. (2003) DNA microarray analysis of Bacillus subtilis sigma factors of extracytoplasmic function family. FEMS Microbiol. Lett. 220(1):155-60). Cells overexpressing sigma factors as well as reporter genes linked to sigma factor promoters were used to show stress regulated gene induction.
Choi et al. described the analysis and up-regulation of metabolic genes that are down-regulated in high-density batch cultures of E. coli expressing human insulin-like growth factor fusion protein (IGF-If) (Choi et al. (2003) Enhanced Production of Insulin-Like Growth Factor I Fusion Protein in Escherichia coli by Coexpression of the Down-Regulated Genes Identified by Transcriptome Profiling App. Envir. Microbio. 69:4737-4742). The focus of this work was on the metabolic changes that occur during high-density conditions after protein induction. Genes that were down regulated after induction of recombinant protein production during high density growth conditions were identified and specific metabolic genes that had been down-regulated were expressed in cells producing recombinant IGF-If. The work showed that increasing metabolic production of certain nucleotide bases and amino acids could increase protein production and that growth rates could be modified by increasing expression of a down-regulated metabolic transporter molecule. These strategies were designed to alter the cellular environment to reduce metabolic stresses associated with the protein production generally or with high density culture.
Protein Degradation
Unwanted degradation of recombinant protein presents an obstacle to the efficient use of certain expression systems. The expression of exogenous proteins often induces stress responses in host cells, which can be, for example, natural defenses to a limited carbon source. All cells contain a large number of genes capable of producing degradative proteins. It is not possible to predict which proteases will be regulated by a given host in response to expression of a particular recombinant protein. For example, the bacteria P. fluorescens contains up to 200 proteases and protease related proteins.
In the cytoplasm of E. coli, proteolysis is generally carried out by a group of proteases and cofactor molecules. Most early degradation steps are carried out by five ATP-dependent Hsps: Lon/La FtsH/HflB, ClpAP, ClpXP, and ClpYQ/HslUV (Gottesman S (1996) Proteases and their targets in Escherichia coli. Annu. Rev. Genet. 30:465-506). Along with FtsH (an inner membrane-associated protease the active site of which faces the cytoplasm), ClpAP and ClpXP are responsible for the degradation of proteins modified at their carboxyl termini by addition of the non-polar destabilizing tail (Gottesman S, et al. (1998). The ClpXP and ClpAP proteases degrade proteins with carboxyl-terminal peptide tails added by the SsrA-tagging system. Genes Dev. 12:1338-1347; Herman C, et al. (1998) Degradation of carboxy-terminal-tagged cytoplasmic proteins by the Escherichia coli protease HflB (FtsH). Genes Dev. 12:1348-1355).
Several approaches have been taken to avoid degradation during recombinant protein production. One approach is to produce host strains bearing mutations in a protease gene. Baneyx and Georgiou, for example, utilized a protease-deficient strain to improve the yield of a protein A-β-lactamase fusion protein (Baneyx F, Georgiou G. (1991) Construction and characterization of Escherichia coli strains deficient in multiple secreted proteases: protease III degrades high-molecular-weight substrates in vivo. J Bacteriol 173: 2696-2703). Park et al. used a similar mutational approach to improve recombinant protein activity 30% compared with the parent strain of E. coli (Park S. et al. (1999) Secretory production of recombinant protein by a high cell density culture of a protease negative mutant Escherichia coli strain. Biotechnol. Progr. 15:164-167). U.S. Pat. Nos. 5,264,365 and 5,264,365 describe the construction of protease-deficient E. coli, particularly multiply protease deficient strains, to produce proteolytically sensitive polypeptides. PCT Publication No. WO 90/03438 describes the production of strains of E. coli that include protease deficient strains or strains including a protease inhibitor. Similarly, PCT Publication No. WO 02/48376 describes E. coli strains deficient in proteases DegP and Prc.
Protein Folding
Another major obstacle in the production of recombinant proteins in host cells is that the cell often is not adequately equipped to produce either soluble or active protein. While the primary structure of a protein is defined by its amino acid sequence, the secondary structure is defined by the presence of alpha helixes or beta sheets, and the ternary structure by covalent bonds between adjacent protein stretches, such as disulfide bonds. When expressing recombinant proteins, particularly in large-scale production, the secondary and tertiary structure of the protein itself is of critical importance. Any significant change in protein structure can yield a functionally inactive molecule, or a protein with significantly reduced biological activity. In many cases, a host cell expresses folding modulators (FMs) that are necessary for proper production of active recombinant protein. However, at the high levels of expression generally required to produce usable, economically satisfactory biotechnology products, a cell often can not produce enough native folding modulator or modulators to process the recombinant protein.
In certain expression systems, overproduction of exogenous proteins can be accompanied by their misfolding and segregation into insoluble aggregates. In bacterial cells these aggregates are known as inclusion bodies. In E. coli, the network of folding modulators/chaperones includes the Hsp70 family. The major Hsp70 chaperone, DnaK, efficiently prevents protein aggregation and supports the refolding of damaged proteins. The incorporation of heat shock proteins into protein aggregates can facilitate disaggregation. However, proteins processed to inclusion bodies can, in certain cases, be recovered through additional processing of the insoluble fraction. Proteins found in inclusion bodies typically have to be purified through multiple steps, including denaturation and renaturation. Typical renaturation processes for inclusion body targeted proteins involve attempts to dissolve the aggregate in concentrated denaturant and subsequent removal of the denaturant by dilution. Aggregates are frequently formed again in this stage. The additional processing adds cost, there is no guarantee that the in vitro refolding will yield biologically active product, and the recovered proteins can include large amounts of fragment impurities.
One approach to reduce protein aggregation is through fermentation engineering, most commonly by reducing the cultivation temperature (see Baneyx F (1999) In vivo folding of recombinant proteins in Escherichia coli. In Manual of Industrial Microbiology and Biotechnology, Ed. Davies et al. Washington, D.C.: American Society for Microbiology ed. 2:551-565 and references therein). The more recent realization that in vivo protein folding is assisted by molecular chaperones, which promote the proper isomerization and cellular targeting of other polypeptides by transiently interacting with folding intermediates, and by foldases, which accelerate rate-limiting steps along the folding pathway, has provided additional approaches combat the problem of inclusion body formation (see for e.g. Thomas J G et al. (1997). Molecular chaperones, folding catalysts and the recovery of active recombinant proteins from E. coli: to fold or to refold. Appl Biochem Biotechnol, 66:197-238).
In certain cases, the overexpression of chaperones has been found to increase the soluble yields of aggregation-prone proteins (see Baneyx, F. (1999) Recombinant Protein Expression in E. coli Curr. Opin. Biotech. 10:411-421 and references therein). The process does not appear to involve dissolution of preformed recombinant inclusion bodies but is related to improved folding of newly synthesized protein chains. For example, Nishihara et al. coexpressed groESL and dnaJK/grpE in the cytoplasm to improve the stability and accumulation of recombinant Cryj2 (an allergen of Japanese cedar pollen) (Nishihara K, Kanemori M, Kitagawa M, Yanagi H, Yura T. 1998. Chaperone coexpression plasmids: differential and synergistic roles of DnaK-DnaJ-GrpE and GroEL-GroES in assisting folding of an allergen of Japanese cedar pollen, Cryj2, in Escherichia coli. Appl. Environ. Microbiol. 64:1694). Lee and Olins also coexpressed GroESL and DnaK and increased the accumulation of human procollagenase by tenfold (Lee S, Olins P. 1992. Effect of overproduction of heat shock chaperones GroESL and DnaK on human procollagenase production in Escherichia coli. JBC 267:2849-2852). The beneficial effect associated with an increase in the intracellular concentration of these chaperones appears highly dependent on the nature of the overproduced protein, and success is by no means guaranteed.
A need exists for processes for development of host strains that show improved recombinant protein or peptide production, activity or solubility in order to reduce manufacturing costs and increase the yield of active products.
It is therefore an object of the invention to provide processes for improving recombinant protein expression in a host.
It is a further object of the invention to provide processes that increase expression levels in host cells expressing recombinant proteins or peptides.
It is another object of the invention to provide processes to increase the levels of soluble protein made in recombinant expression systems.
It is yet another object of the invention to provide processes to increase the levels of active protein made in recombinant expression systems.

Process for improved protein expression by strain engineering


The process of the present invention involves reducing the sulfur and/or nitrogen content of a distillate feedstock to produce a refinery transportation fuel or blending components for refinery transportation fuel, by contacting the feedstock with an oxygen-containing gas in an oxidation zone at oxidation conditions in the presence of an oxidation catalyst comprising a zeolitic material, TIQ-6, whose chemical composition corresponds to the formula, expressed as oxides,SiO2:zZO2:mMO2:xX2O3:aH2O                Wherein        Z is Ge, Sn,        z is between 0 and 0.25 mol.mol−1         M is Ti or Zr,        M has a value between 0.00001 and 0.25, preferably between 0.001 and 0.01, and        a=has a value between 0 and 2.

It is well known that internal combustion engines have revolutionized transportation following their invention during the last decades of the 19th century. While others, including Benz and Gottleib Wilhelm Daimler, invented and developed engines using electric ignition of fuel such as gasoline, Rudolf C. K. Diesel invented and built the diesel engine which employs compression for auto-ignition of the fuel in order to utilize low-cost organic fuels. Development of improved diesel engines for use in transportation has proceeded hand-in-hand with improvements in diesel fuel compositions. Modern high performance diesel engines demand ever more advanced specification of fuel compositions, but cost remains an important consideration.
At the present time most fuels for transportation are derived from natural petroleum. Indeed, petroleum as yet is the world's main source of hydrocarbons used as fuel and petrochemical feedstock. While compositions of natural petroleum or crude oils are significantly varied, all crudes contain sulfur compounds and most contain nitrogen compounds which may also contain oxygen, but oxygen content of most crudes is low. Generally, sulfur concentration in crude is less than about 8 percent, with most crudes having sulfur concentrations in the range from about 0.5 to about 1.5 percent. Nitrogen concentration is usually less than 0.2 percent, but it may be as high as 1.6 percent.
Crude oil seldom is used in the form produced at the well, but is converted in oil refineries into a wide range of fuels and petrochemical feedstocks. Typically fuels for transportation are produced by processing and blending of distilled fractions from the crude to meet the particular end use specifications. Because most of the crudes available today in large quantity are high in sulfur, the distilled fractions must be desulfurized to yield products which meet performance specifications and/or environmental standards. Sulfur-containing organic compounds in fuels continues to be a major source of environmental pollution. During combustion they are converted to sulfur oxides, which in turn, give rise to sulfur oxyacids and, also, contribute to particulate emissions.
Even in newer, high performance diesel engines combustion of conventional fuel produces smoke in the exhaust. Oxygenated compounds and compounds containing few or no carbon-to-carbon chemical bonds, such as methanol and dimethyl ether, are known to reduce smoke and engine exhaust emissions. However, most such compounds have high vapor pressure and/or are nearly insoluble in diesel fuel, and they have poor ignition quality, as indicated by their cetane numbers. Furthermore, other methods of improving diesel fuels by chemical hydrogenation to reduce their sulfur and aromatics contents, also causes a reduction in fuel lubricity. Diesel fuels of low lubricity may cause excessive wear of fuel injectors and other moving parts which come in contact with the fuel under high pressures.
Distilled fractions used for fuel or a blending component of fuel for use in compression ignition internal combustion engines (Diesel engines) are middle distillates that usually contain from about 1 to 3 percent by weight sulfur. In the past a typical specification for Diesel fuel was a maximum of 0.5 percent by weight. By 1993 legislation in Europe and United States limited sulfur in Diesel fuel to 0.3 weight percent. By 1996 in Europe and United States, and 1997 in Japan, maximum sulfur in Diesel fuel was reduced to no more than 0.05 weight percent. This worldwide trend must be expected to continue to even lower levels for sulfur.
The US Environmental Protection Agency is targeting a level of sulfur less than 15 ppm in 2006 for on-road diesel. The European Union specification will be less than 50 ppm in 2005. Further the World Wide Fuels Charter as supported by all global automobile manufacturers proposes even more stringent sulfur requirements of 5 to 10 ppm for the Category IV fuels for "advanced " countries. In order to comply with these regulations for ultra-low sulfur content fuels, refiners will have to make fuels having even lower sulfur levels at the refinery gate. Thus refiners are faced with the challenge of reducing the sulfur levels in fuels and in particular diesel fuel within the timeframes prescribed by the regulatory authorities.
In one aspect, pending introduction of new emission regulations in California and other jurisdictions has prompted significant interest in catalytic exhaust treatment. Challenges of applying catalytic emission control for the diesel engine, particularly the heavy-duty diesel engine, are significantly different from the spark ignition internal combustion engine (gasoline engine) due to two factors. First, the conventional three-way catalyst (TWC) catalyst is ineffective in removing NOx emissions from diesel engines, and second, the need for particulate control is significantly higher than with the gasoline engine.
Several exhaust treatment technologies are emerging for control of Diesel engine emissions, and in all sectors the level of sulfur in the fuel affects efficiency of the technology. Sulfur is a catalyst poison that reduces catalytic activity. Furthermore, in the context of catalytic control of Diesel emissions, high fuel sulfur also creates a secondary problem of particulate emission, due to catalytic oxidation of sulfur and reaction with water to form a sulfate mist. This mist is collected as a portion of particulate emissions.
Compression ignition engine emissions differ from those of spark ignition engines due to the different method employed to initiate combustion. Compression ignition requires combustion of fuel droplets in a very lean air/fuel mixture. The combustion process leaves tiny particles of carbon behind and leads to significantly higher particulate emissions than are present in gasoline engines. Due to the lean operation the CO and gaseous hydrocarbon emissions are significantly lower than the gasoline engine. However, significant quantities of unburned hydrocarbon are adsorbed on the carbon particulate. These hydrocarbons are referred to as SOF (soluble organic fraction).
While an increase in combustion temperature can reduce particulate, this leads to an increase in NOx emission by the well-known Zeldovitch mechanism. Thus, it becomes necessary to trade off particulate and NOx emissions to meet emissions legislation.
Available evidence strongly suggests that ultra-low sulfur fuel is a significant technology enabler for catalytic treatment of diesel exhaust to control emissions. Fuel sulfur levels of below 15 ppm, likely, are required to achieve particulate levels below 0.01 g/bhp-hr. Such levels would be very compatible with catalyst combinations for exhaust treatment now emerging, which have shown capability to achieve NOx emissions around 0.5 g/bhp-hr. Furthermore, NOx trap systems are extremely sensitive to fuel sulfur and available evidence suggests that they would need sulfur levels below 10 ppm to remain active.
In the face of ever-tightening sulfur specifications in transportation fuels, sulfur removal from petroleum feedstocks and products will become increasingly important in years to come.
Conventional hydrodesulfurization (HDS) catalysts can be used to remove a major portion of the sulfur from petroleum distillates for the blending of refinery transportation fuels, but they are not efficient for removing sulfur from compounds where the sulfur atom is sterically hindered as in multi-ring aromatic sulfur compounds. This is especially true where the sulfur heteroatom is doubly hindered (e.g., 4,6-dimethyldibenzothiophene). These hindered dibenzothiophenes predominate at low sulfur levels such as 50 to 100 ppm and would require severe process conditions to be desulfurized. Using conventional hydrodesulfurization catalysts at high temperatures would cause yield loss, faster catalyst coking, and product quality deterioration (e.g., color). Using high pressure requires a large capital outlay.
In order to meet stricter specifications in the future, such hindered sulfur compounds will also have to be removed from distillate feedstocks and products. There is a pressing need for economical removal of sulfur from distillates and other hydrocarbon products.
The art is replete with processes said to remove sulfur from distillate feedstocks and products. One known method involves the oxidation of petroleum fractions containing at least a major amount of material boiling above very high-boiling hydrocarbon materials (petroleum fractions containing at least a major amount of material boiling above about 550° F.) followed by treating the effluent containing the oxidized compounds at elevated temperatures to form hydrogen sulfide (500° F. to 1350° F.) and/or hydroprocessing to reduce the sulfur content of the hydrocarbon material. See, for example, U.S. Pat. No. 3,847,798 (Jin Sun Yoo, et al) and U.S. Pat. No. 5,288,390 (Vincent A. Durante). Such methods have proven to be of only limited utility since only a rather low degree of desulfurization is achieved. In addition, substantial loss of valuable products may result due to cracking and/or coke formation during the practice of these methods. Therefore, it would be advantageous to develop a process which gives an increased degree of desulfurization while decreasing cracking or coke formation.
Several different oxygenation methods for improving fuels have also been described in the past. For example, U.S. Pat. No. 2,521,698 (G. H. Denison, Jr. et al.) describes a partial oxidation of hydrocarbon fuels as improving cetane number. This patent suggests that the fuel should have a relatively low aromatic ring content and a high paraffinic content. U.S. Pat. No. 2,912,313 (James B. Hinkamp et al.) states that an increase in cetane number is obtained by adding both a peroxide and a dihalo compound to middle distillate fuels. U.S. Pat. No. 2,472,152 (Adalbert Farkas et al.) describes a method for improving the cetane number of middle distillate fractions by the oxidation of saturated cyclic hydrocarbon or naphthenic hydrocarbons in such fractions to form naphthenic peroxides. This patent suggests that the oxidation may be accelerated in the presence of an oil-soluble metal salt as an initiator, but is preferably carried out in the presence of an inorganic base. However, the naphthenic peroxides formed are deleterious gum initiators. Consequently, gum inhibitors such as phenols, cresols and cresyic acids must be added to the oxidized material to reduce or prevent gum formation. These latter compounds are toxic and carcinogenic.
U.S. Pat. No. 4,494,961 (Chaya Venkat et al.) relates to improving the cetane number of raw, untreated, highly aromatic, middle distillate fractions having a low hydrogen content by contacting the fraction at a temperature of from 50° C. to 350° C. and under mild oxidizing conditions in the presence of a catalyst which is either (i) an alkaline earth metal permanganate, (ii) an oxide of a metal of Groups IB, IIB, IIIB, IVB, VB, VIB, VIIB or VIIIB of the periodic table, or a mixture of (i) and (ii).
European Patent Application 0 252 606 A2 also relates to improving the cetane rating of a middle distillate fuel fraction which may be hydro-refined by contacting the fraction with oxygen or oxidant, in the presence of catalytic metals such as tin, antimony, lead, bismuth and transition metals of Groups IB, IIB, VB, VIB, VIIB and VIIIB of the periodic table, preferably as an oil-soluble metal salt. The application states that the catalyst selectively oxidizes benzylic carbon atoms in the fuel to ketones.
U.S. Pat. No. 4,723,963 (William F. Taylor) suggests that cetane number is improved by including at least 3 weight percent oxygenated aromatic compounds in middle distillate hydrocarbon fuel boiling in the range of 160° C. to 400° C. This patent states that the oxygenated alkylaromatics and/or oxygenated hydroaromatics are preferably oxygenated at the benzylic carbon proton.
U.S. Pat. No. 6,087,544 (Robert J. Wittenbrink et al.) relates to processing a distillate feedstream to produce distillate fuels having a level of sulfur below the distillate feedstream. Such fuels are produced by fractionating a distillate feedstream into a light fraction, which contains only from about 50 to 100 ppm of sulfur, and a heavy fraction. The light fraction is hydrotreated to remove substantially all of the sulfur therein. The desulfurized light fraction, is then blended with one half of the heavy fraction to produce a low sulfur distillate fuel, for example 85 percent by weight of desulfurized light fraction and 15 percent by weight of untreated heavy fraction reduced the level of sulfur from 663 ppm to 310 ppm. However, to obtain this low sulfur level only about 85 percent of the distillate feedstream is recovered as a low sulfur distillate fuel product.
U.S. patent application Publication 2002/0035306 A1 (Gore et al.) discloses a multi-step process for desulfurizing liquid petroleum fuels that also removes nitrogen-containing compounds and aromatics. The process steps are thiophene extraction; thiophene oxidation; thiophene-oxide and dioxide extraction; raffinate solvent recovery and polishing; extract solvent recovery; and recycle solvent purification.
The Gore et al. process seeks to remove 5-65% of the thiophenic material and nitrogen-containing compounds and parts of the aromatics in the feedstream prior to the oxidation step. While the presence of aromatics in diesel fuel tends to suppress cetane, the Gore et al. process requires an end use for the extracted aromatics. Further, the presence of an effective amount of aromatics serves to increase the fuel density (Btu/gal) and enhance the cold flow properties of diesel fuel. Therefore it is not prudent to extract an inordinate amount of the aromatics.
With respect to the oxidation step, the oxidant is prepared in situ or is previously formed. Operating conditions include a molar ratio of H2O2 to S between about 1:1 and 2.2:1; acetic acid content between about 5 and 45% of feed, solvent content between 10 and 25% of feed, and a catalyst volume of less than about 5,000 ppm sulfuric acid, preferably less than 1,000 ppm. Gore et al. also discloses the use of an acid catalyst in the oxidation step, preferably sulfuric acid. The use of sulfuric acid as an oxidizing acid is problematic in that corrosion is a concern when water is present and hydrocarbons can be sulfonated when a little water is present.
According to Gore et al. the purpose of the thiophene-oxide and dioxide extraction step is to remove more than 90% of the various substituted benzo- and dibenzo thiophene-oxides and N-oxide compounds plus a fraction of the aromatics with an extracting solvent that is aqueous acetic acid with one or more co-solvents.
U.S. Pat. No. 6,368,495 B1 (Kocal et al.) also discloses a multi-step process for the removal of thiophenes and thiophene derivatives from petroleum fractions. This subject process involves the steps of contacting a hydrocarbon feed stream with an oxidizing agent followed by the contact of the oxidizing step effluent with a solid decomposition catalyst to decompose the oxidized sulfur-containing compounds thereby yielding a heated liquid stream and a volatile sulfur compound. The subject patent discloses the use of oxidizing agents such as alkyl hydroperoxides, peroxides, percarboxylic acids, and oxygen.
WO 02/18518 A1 (Rappas et al) discloses a two-stage desulfurization process which is utilized downstream of a hydrotreater. The process involves an aqueous formic acid based, hydrogen peroxide biphasic oxidation of a distillate to convert thiophenic sulfur to corresponding sulfones. During the oxidation process, some sulfones are extracted into the oxidizing solution. These sulfones are removed from the hydrocarbon phase by a subsequent phase separation step. The hydrocarbon phase containing remaining sulfones is then subjected to a liquid-liquid extraction or solid adsorption step.
The use of formic acid in the oxidation step is not advisable. Formic acid is relatively more expensive than acetic acid. Further, formic acid is considered a "reducing" solvent and can hydride certain metals thereby weakening them. Therefore, exotic alloys are required to handle formic acid. These expensive alloys would have to be used in the solvent recovery section and storage vessels. The use of formic acid also necessitates the use of high temperatures for the separation of the hydrocarbon phase from the aqueous oxidant phase in order to prevent the appearance of a third precipitated solid phase. It is believed this undesirable phase can be formed due to the poor lipophilicity of formic acid. Therefore at lower temperatures, formic acid cannot maintain in solution some of the extracted sulfones.
U.S. Pat. No. 6,171,478 B1 (Cabrera et al.) discloses yet another complex multi-step desulfurization process. Specifically, the process involves a hydrodesulfurization step, an oxidizing step, a decomposition step, and a separation step wherein a portion of the sulfur-oxidated compounds are separated from the effluent stream of the decomposition step. The aqueous oxidizing solution used in the oxidizing step preferably contains acetic acid and hydrogen peroxide. Any residual hydrogen peroxide in the oxidizing step effluent is decomposed by contacting the effluent with a decomposition catalyst.
The separation step is carried out with a selective solvent to extract the sulfur-oxidated compounds. Per the teachings of Cabrera et al. the preferred selective solvents are acetonitrile, dimethyl formamide, and sulfolane.
A number of solvents have been proposed for removing the oxidized sulfur compounds. For example, in U.S. Pat. No. 6,160,193 (Gore) teaches the use of a wide variety of solvents suitable for use in the extraction of sulfones. The preferred solvent is Dimethylsulfoxide (DMSO).
A study of a similar list of solvents used in the extraction of sulfur compounds was published by Otsuki, S.; Nonaka, T.; Takashima, N.; Qian, W.; Ishihara, A.; Imai, T.; Kabe, T. "Oxidative Desulfurization of Light Gas Oil and Vacuum Gas Oil by Oxidation and Solvent Extraction" Energy & Fuels 2000, 14, 1232. That list is displayed below:                N,N-Dimethylformamide (DMF)        Methanol        Acetonitrile        Sulfolane
Gore states that there is a relationship between the solvent's polarity with the solvent's extraction efficiency. All of the solvents listed in the patent and the paper are desirably immiscible with the diesel. They are all characterized as either polar protic or aprotic solvents.
WO 01/32809 discloses another process for selectively oxidizing distillate fuel or middle distillates. The subject reference discloses that oxidized distillate fuels such that hydroxyl and or carbonyl groups are chemically bound to paraffinic molecules in the fuel results in a reduction in particulates generated upon combustion of the fuel versus unoxidized fuel. The reference discloses a process for selectively oxidizing saturated aliphatic or cyclic compounds in the fuel in the presence of various titanium containing silicon based zeolites with peroxides, ozone or hydrogen peroxide such that hydroxyl or carbonyl groups are formed.
U.S. Pat. No. 6,402,939 B1 (Yen et al.) discloses a process for the oxidative desulfurization of fossil fuels using ultrasound. Briefly liquid fossil fuel is combined with an acidic aqueous solution comprising water and an hydroperoxide to form a multiphase reaction mixture followed by applying ultrasound to the multiphase reaction medium for a time sufficient to cause oxidation of sulfides to sulfones with are subsequently extracted.
U.S. patent application Publication 2001/0015339 A1 (Sherman) discloses a method of removing sulfur compounds from diesel fuel that involves forming oxidizing gas into sub micron size bubbles and dispersing these bubbles into flowing diesel fuel to oxidize the sulfur compounds into sulfoxides and/or sulfones.
In view of the above, it is clear that there is a need for a less complex, economic distillate or diesel desulfurization process that does not employ expensive hydrotreating technologies involving greater hydrogen useage or oxidation technologies that employ the use of expensive chemical oxidizing agents and avoids the attendant complex handling and corrosion issues.
The present invention provides for a relatively simple selective desulfurization process wherein a distillate feedstock is contacted with an oxygen-containing gas at oxidation conditions in the presence of a heterogeneous catalyst comprising a zeolitic material, TIQ-6 whose chemical composition corresponds to the formula, expressed as oxides,SiO2:zZO2:mMO2:xX2O3:aH2O
Wherein
Z is Ge, Sn,
z is between 0 and 0.25 mol.mol−1
M is Ti or Zr,
M has a value between 0.00001 and 0.25, preferably between 0.001 and 0.01, and
a=has a value between 0 and 2.
In another embodiment, the catalyst comprises METIQ-6 which is a TIQ-6 material that has organic groups anchored on its surface. This METIQ-6 material has a chemical composition which can be represented by the formula:SiO2:yYRpO2-p/2:zZO2:mMO2:xX2O3:aH2O
wherein                R is selected among hydrogen, alkyl groups with 1 to 22 carbon atoms, aryl groups with 6 to 36 carbon atoms, aromatic groups with 6 to 36 carbon atoms, polyaromatic groups with 6 to 36 carbon atoms and these groups are selected among non functionalized groups and fictionalized groups with functional groups selected among acid, amino, thiol, sulphonic and tetra-alkyl ammonium groups,        Y is Si, Ge, Sn or Ti and is directly joined to atoms making up a structure by means of C—Y bonds,        p has a value between 1 and 3,        y has a value between 0.001 and 1,        Z is GE or Sn,        z has a value between 0 and 0.25 mol.mol−1,        M is Ti or Zr,        m has a value between 0.00001 and 0.25, preferably between 0.001 and 0.1,        X is Al, Ga or B,        x has a value between 0 and 1, and        a has a value between 0 and 2.

Preparation of components for refinery blending of transportation fuels


A logic circuit for quantum-resistant cryptoprocessing. The logic circuit includes a first plurality of multiplexers, a second plurality of multiplexers, a plurality of AND gates, a third plurality of multiplexers, a plurality of shift registers, a plurality of inverters, a fourth plurality of multiplexers, a plurality of adders, a plurality of XOR gates, a fifth plurality of multiplexers, and a plurality of parallel outputs.

To implement secure channels for communications, a set of operations should be executed for cryptographic primitives such as public key encryption and decryption. Classic public key cryptosystems are computationally complex and may not be efficiently implemented on resource-constrained devices. Moreover, classic public key cryptosystems may rely on hard problems that may have polynomial time solutions using quantum search algorithm. Therefore, classic public key cryptosystems may not be quantum-resistant and may require very large keys to remain secure, which may not be practical due to hardware implementation complexity. There are alternative cryptosystems that rely on quantum-resistant hard problems. Ring learning with error (Ring-LWE) cryptosystems may rely on hardness of LWE problem. However, implementation of Ring-LWE may require some operations on ring of polynomials that may lead to high complexity. As a result, implementation of Ring-LWE on resource-constrained devices may be challenging.
There is, therefore, a need for a cryptoprocessing circuit that implements a quantum-resistant cryptoprocessing method with low complexity. There is also a need for a cryptoprocessing circuit that implements a quantum-resistant cryptoprocessing method with high speed.


The disclosed concept relates to electrical isolation between power electronic and cooling and/or mounting components and, in particular, a ceramic layer disposed on one or more portions of the cooling and/or mounting components to provide electrical isolation, as well as, a thermally conductive path to remove heat produced by the power electronic component.

Field
The disclosed concept relates generally to power electronic devices, cooling and/or mounting devices therefor and, ceramic coatings applied to the cooling and/or mounting devices.
Background Information
It is known in the art to provide cooling and/or mounting devices with power electronic devices for the purpose of removing at least a portion of the heat generated by the power electronic devices, such as, one or more diodes or insulated-gate bipolar transistors. It is also known that in certain instances the power electronic devices may operate at voltages that exceed their isolation rating. Therefore, the cooling and/or mounting devices are also at an elevated potential voltage. It is necessary to isolate the power electronic devices from ground to prevent arcing or ground currents, which can cause noise on a system, degrade or damage a system, and potentially lead to operator injury or death. If the cooling and/or mounting devices use electrically conductive cooling medium, such as water, the entire water circuit can serve as a path to ground thereby resulting in the cooling circuit itself being unsafe.
Isolation pads and films are known for use in isolating the power electronic devices. However, there are disadvantages associated with many of these pads and films. For example, it has been found that the pads or films can have poor thermal conductivity and/or poor adhesion. In some instances, a thermal grease or epoxy may be required to adhere the pad or film to the surface of the device. The use of an intermediate layer for purposes of enhancing adherence may result in increased contact losses and reduced effective conductivity.
There is room for improvement in power electronic devices and the cooling and/or mounting devices associated therewith. It would be advantageous for the cooling and/or mounting devices to include a ceramic coating or layer applied to surfaces in contact with the liquid cooling medium that circulates within the cooling and/or mounting device, to provide a means for thermal transfer, while providing electrical isolation.

Ceramic coated flow channels for electrical isolation and thermal transfer


The present invention provides a cosmetic which is superior in both characteristics of feel and spread at the time of application. The cosmetic is a cosmetic comprising an amphoteric urethane resin having carboxyl group(s) and tertiary amino group(s) in a molecule, and a silicone polymer.

The present invention relates to cosmetics containing an amphoteric urethane resin and a silicone polymer.
As a base resin for cosmetics such as hair fixatives, for example, water-soluble resins such as nonionic (non-ionic) polyvinyl pyrrolidone (PVP), cationic acrylic resin or cellulose, anionic acrylic resin or polyvinyl acetate, and amphoteric acrylic resin or polyvinyl acetate have hitherto been used. Hair fixatives comprising these water-soluble resins as the base resin have merits such as high curl holding power and excellent durability, but have problems such as poor touch, which is important for cosmetics, and drastically poor feel.
On the other hand, the present inventors found that an amphoteric urethane resin having carboxyl group(s) and tertiary amino group(s) in a molecule can provide excellent feel because of the elasticity and strong toughness of the urethane resin and filed a patent application with respect to a resin composition for cosmetics, comprising the amphoteric urethane resin as the base resin (Japanese Patent Application No Hei 10-27595).
However, the cosmetic comprising the amphoteric urethane resin as the base resin is superior in feel, but has such a problem that a friction coefficient of the surface is large and spread at the time of application is inferior because of poor surface smoothness.
The present invention has been accomplished under these circumstances and an object thereof is to provide a cosmetic which is superior in both characteristics of touch and spread at the time of application.
To attain the object described above, the present invention is directed to a cosmetic comprising an amphoteric urethane resin having carboxyl group(s) and tertiary amino group(s) in a molecule, and a silicone polymer.
The present inventors have studied intensively to solve the problems such as surface smoothness, which is a weak point in case of using the amphoteric urethane resin. As a result, they have found that, when using an amphoteric urethane resin in combination with a silicone polymer, good results are obtained. That is, since the compatibility of the said amphoteric urethane resin with the silicone polymer is not high and the silicone polymer has stronger hydrophobicity, the amphoteric urethane resin and silicone polymer cause micro phase separation and the silicone polymer is unevenly distributed on the surface, thereby making it possible to provide the surface with the smoothness. As a result, they have found that a cosmetic comprising the amphoteric urethane resin in combination with the silicone polymer is superior in spread at the time of application without impairing the touch when using the amphoteric urethane resin alone, thus completing the present invention.
When using an aqueous solution or a water dispersion of the silicone polymer as the silicone polymer, the compatibility with the amphoteric urethane resin is enhanced to some degree, thereby making it possible to prepare a cosmetic having good stability.
When a structural unit derived from ethylene oxide is introduced, as a nonionic hydrophilic component, into the structure of the amphoteric urethane resin, sufficient hydrophilicity can be obtained and the hair washability is particularly improved when using as a hair cosmetic.
By introducing polysiloxane bond(s) into the structure of the said amphoteric urethane resin, the touch is further improved when using as a hair cosmetic.
The embodiments of the present invention will now be described below.
The cosmetics of the present invention can be obtained by using an amphoteric urethane resin having carboxyl group(s) and tertiary amino group(s) in a molecule, and a silicone polymer.
The cosmetics of the present invention are used as hair cosmetics such as foam hair fixative, gel-like hair fixative, aerosol spray hair fixative, pump spray hair fixative and creamy hair fixative; skin care cosmetics such as shaving cream, skin care lotion and sunscreen lotion; and make-up cosmetics such as nail polish, mascara and foundation; and are particularly preferably used as hair cosmetics.
The amphoteric urethane resin having carboxyl group(s) and tertiary amino group(s) in a molecule can be prepared, for example, by reacting a polyol compound (component A), a polyisocyanate compound (component B) and a compound having active hydrogens) and carboxyl group(s) (component C) in the presence of excess isocyanate groups to form an isocyanate group-containing prepolymer, and reacting the isocyanate group-containing prepolymer with a compound having active hydrogen(s) and tertiary amino group(s) (component D). Alternatively, the amphoteric urethane resin can also be prepared by replacing the sequence of the reaction between the above specific components C and D, that is, by reacting the above components A, B. and D in the presence of excess isocyanate groups to form an isocyanate group-containing prepolymer, and reacting the isocyanate group-containing prepolymer with the above specific component C. Such a method makes it possible to prepare an amphoteric urethane resin simply and safely as compared with a conventional method. In the above preparation method, when both specific components C and D are simultaneously reacted, together with the components A and B, the carboxyl group(s) in the component C and the tertiary amino group(s) in the component D form(s) a salt, which is insoluble in the reaction system. As a result, the reaction with the isocyanate compound does not occur even in the presence of the OH group(s), thereby making it impossible to prepare a desired amphoteric urethane resin.
The above polyol compound (component A) is not specifically limited as far as it can be used in the preparation of a normal polyurethane, and examples thereof include polyester poylol, polyether polyol, polycarbonate polyol, polybutadiene polyol, polyisoprene polyol, polyolefin polyol and polyacrylate polyol etc. These polyol compounds are used alone or in combination. Among these polyol compounds, polyester poylol and polyether polyol are preferably used.
Examples of the polyester polyol include those obtained by polycondensing at least one of dicarboxylic acids such as succinic acid glutaric acid, adipic acid, sebacic acid, azelaic acid, maleic acid, fumaric acid, phthalic acid and terephthalic acid with at least one of polyhydric alcohols such as ethylene glyol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, neopentyl glycol, 1,8-octanediol, 1,10-decanediol, diethylene glycol, spiro-glycol and trimethylolpropane, etc., and those obtained by the ring-opening polymerization of lactones.
Example of the polyether polyol include polyhydric alcohols used in the synthesis of the said polyester polyols, phenols such as bisphenol A, or those obtained by the ring-opening addition polymerization of primary amines or secondary amines and cyclic ether such as ethylene oxide, propylene oxide, oxetane and tetrahydrofuran. Examples thereof include polyoxyethylene polyol, polyoxypropylene polyol, polyoxytetramethylene polyol, and those obtained by the ring-opening addition polymerization of bisphenol A and at least one of propylene oxide and ethylene oxide, etc. (in case of a copolymer it may be either a block copolymer or a random copolymer).
The polyisocyanate compound (component B) is not specifically limited, and examples thereof include organic diisocyanate compounds such as aliphatic diisocyanate compound, alicyclic diisocyanate compound and aromatic diisocyanate compound. These compounds may be used alone or in combination.
Example of the aliphatic diisocyanate compound includes ethylene diisocyanate, 2,2,4-trimethylhexa-methylene diisocyanate, 1,6-hexamethylene diisocyanate, etc. Examples of the alicyclic diisocyanate compound includes hydrogenated 4,4xe2x80x2-diphenylmethane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate and norbornane diisocyanate, etc. Examples of the aromatic diisocyanate compound includes 4,4xe2x80x2-diphenylmethane diisocyanate, xylylene diisocyanate, toluene diisocyanate and naphthalene diisocyanate, etc. Among these compounds, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, norbornane diisocyanate, etc. are preferable because of the excellent light resistance and low price.
The compound (component C) having active hydrogen(s) and carboxyl group(s) is not specifically limited as far as it is a compound having at least one active hydrogen and at least one carboxyl group in a molecule, and examples thereof include dimethylolpropionic acid (DMPA), dimethylolbutanoic acid, carboxyl group-containing polycaprolactone diol, etc. These compounds may be used alone or in combination.
The compound (component D) having the above active hydrogen(s) and tertiary amino group(s) is not specifically limited as far as it is a compound having at least one active hydrogen and at least one tertiary amino group in a molecule, and examples thereof include N-alkyldialkanolamine compound such as N-methyidiethanolamine and N-butylidiethanolamine, and dimethylaminoethanol, etc. These compounds may be used alone or in combination.
In the production of an isocyanate group-containing prepolymer by using the above respective components, chain extenders or molecular weight inhibitors can be used for the purpose of controlling various characteristics of the amphoteric urethane resin as a final product.
The chain extender is not specifically limited and examples thereof include low-molecular polyol, amines, etc. Examples of the low-molecular polyol includes glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, diethylene glycol, 1,6-hexanediol, spiro-glycol, cyclohexyl dimethanol, hydrogenated bisphenol A, neopentyl glycol, bis(beta-hydroxyethoxy)benzene, and xylylene glycol; and triol such as trimethylolpropane and glycerin. Examples of the amines include ethylenediamine, propylenediamine, piperazine, hydrazine, isophoronediamine methylene(bis-o-chloroaniline) and propylene glycol having amino groups at both ends, etc.
Examples of the molecular weight inhibitor includes propylene glycol having an amino group at one end, etc.
In the production of the amphoteric urethane resin, solvents can be used as needed. For example, organic solvents capable of dissolving both raw materials and polyurethane to be prepared are preferably used. Examples of the organic solvent includes amides such as N-methylpyrrolidone, dimethylformamide and dimethylacetamide; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate; cellosolve acetate, cellosolve ether, etc.
In the production of the amphoteric urethane resin, the dispersibility in water can be provided by neutralizing the carboxyl group(s) or tertiary amino group(s) incorporated into the molecule with a neutralizing agent. Examples of the neutralizing agent for the said carboxyl group(s) includes triethylamine, trimethylamine, 2-amino-2-methyl-1-propanol, triethanolamine, potassium hydroxide, sodium hydroxide, etc. Examples of the nutralizing agent for the said tertiary amino group(s) include acetic acid, hydrochloric acid, sulfuric, nitric acid and dimethylsulfuric acid, etc.
In the production of the amphoteric urethane resin, polymerization catalysts known in the field of polyurethane can be used, and examples thereof include tertiary amine catalyst, organometallic catalyst, etc. Examples of the tertiary amine catalyst includes [2,2,2]diazabicyclooctane (DABCO), tetramethylene-iamine, N-methyl morphorine and diazabicycloundecene (DBU), etc. Examples of the organometallic catalyst includes dibutyltin dilaurate, etc.
As the amphoteric urethane resin, in view of the hair washability, those having structural unit(s) derived from ethylene oxide (EO) in the structure are preferably used.
Examples of the structural unit derived from the said EO includes EO unit represented by the general formula (I) described below, propylene oxide (hereinafter abreviated to xe2x80x9cPOxe2x80x9d) unit represented by the general formula (II) described below, etc., and the EO unit is preferably used.
The above amphoteric urethane resin may have both EO and PO units. A proportion of the EO unit to the PO unit is preferably within a range from 10/10 to 2/8, and particularly preferably from 10/0 to 4/6, on a weight basis.
The repeating number n of the EO unit in the general formula (I) is preferably set within a range from 3 to 300, and particularly preferably from 20 to 120. When the n is less than 3, sufficient hydrophilicity can not be provided because of too small amount of the EO unit(s) to be incorporated into the amphoteric urethane resin and, therefore, sufficient hair washability are not likely to be obtained. On the other hand, when n exceeds 300, an adverse influence is likely to be exerted on the moisture resistance or the like because of too strong hydrophilicity of the amphoteric urethane resin. Furthermore, the repeating number m of the PO unit in the general formula (II) is preferably set within a range from 3 to 300, and particularly preferably from 20 to 120. When the amphoteric urethane resin has both EO and PO units, (n+m) is preferably set within a range from 3 to 300, and particularly preferably from 20 to 120.
The amphoteric urethane resin having structural unit(s) derived from ethylene oxide (EO) can be prepared, for example, by reacting a polyol compound (component A), a polyisocyanate compound (component B), a polyethylene oxide derivatives having active hydrogen(s), and a compound having active hydrogen(s) and carboxyl group(s) (component C) in the presence of excess isocyanate groups to form an isocyanate group-containing prepolymer, and reacting the isocyanate group-containing prepolymer with a compound having active hydrogen(s) and tertiary amino group(s) (component D). Alternatively, the amphoteric urethane resin can also be prepared by replacing the sequence of the reaction between the above components C and D. As the above components A to D, the same compounds as those described above can be used.
Examples of the polyethylene oxide derivative having active hydrogen(s) to be used together with the above components A to D is not specifically limited as far as it is capable of introducing a structural unit derived from ethylene oxide (EO) into the structure of the above amphoteric urethane resin, and examples thereof include polyoxyethylene glycol (PEG), polyoxyethylene polyoxypropylene glycol (EOPO block copolymer), etc. Among these, polyoxyethylene glycol is preferably used. The above polyoxyethylene oxide derivative may be any of a type wherein an OH group is introduced at both ends, a type wherein an NH2 group is introduced at both ends, a type wherein an OH group is introduced at one end, and a type wherein an NH2 group is introduced at one end. When using the type wherein an OH group is introduced at both ends or a type wherein an NH2 group is introduced at both ends, an amphoteric urethane resin having the EO unit(s) in a principal chain is obtained. When using the type wherein an OH group is introduced at one end or a type wherein an NH2 group is introduced at one end, an amphoteric urethane resin having EO unit(s) at its side chain(s) or end(s) is obtained.
The molecular weight of the specific polyethylene oxide derivative is preferably within a range from 200 to 20000, and particularly preferably from 1000 to 10000.
To further improve the feel, those having polysiloxane bond(s) in the structure are preferably used as the amphoteric urethane resin.
The repeating number n of a siloxane bond (Sixe2x80x94O) is preferably within a range from 5 to 300, and particularly preferably from 20 to 150. When n is less than 5, it becomes difficult to obtain the sufficient effect on the touch, coming properties, etc. obtained intrinsically by introducing the polysiloxane bond(s) because of too small amount of the polysiloxane bond(s) in the resulting amphoteric urethane resin. On the other hand, when n exceeds 300, the compatibility with other raw materials become inferior because of high hydrophobicity, thereby making it difficult to react them. Furthermore, the adhesion to hair is likely to be inhibited because of too high hydrophobicity of the resulting polymer.
The amphoteric urethane resin having the said polysiloxane bond(s) can be prepared, for example, by reacting a polyol compound (component A), a polyisocyanate compound (component B), a polysiloxane compound having active hydrogen(s) and a compound having active hydrogen(s), and carboxyl group(s) (component C) in the presence of excess isocyanate groups to form an isocyanate group-containing prepolymer, and reacting the isocyanate group-containing prepolymer with a compound having active hydrogen(s) and tertiary amino group(s) (component D). Alternatively, the amphoteric urethane resin can also be prepared by replacing the sequence of the reaction between the above components C and D. As the above components A to D, the same compounds as those described above can be used.
The polysilOxane compound having active hydrogen(s) to be used together with the above components A to D is not specifically limited as far as it is capable of introducing polysiloxane bond(s) into the structure of the amphoteric urethane resin, and examples thereof include polydialkylsiloxanediol, polydialkyl-siloxanemonool, polydialkylsiloxanediamine, polydialkyl-siloxanemonoamine, etc. These compounds may be used alone or in combination. The alkyl group(s) to be combined with Si of the respective siloxane bonds of the said polydialkylsiloxanediol preferably has 1 to 10 carbon atoms, and particularly preferably 1 to 5 carbon atoms. The above polysiloxane compound may contain various siloxane bonds wherein the number of carbon atoms of the alkyl group(s) to be combined with Si of the siloxane bonds varies. Specific examples of the polydialkyl-siloxanediol include polydimethylsiloxanediol, polymethyl-ethylsiloxanediol, etc. Examples of the polydialkyl-siloxanemonool include polydimethyl-siloxanemonool, polymethylethyl-siloxanemonool, etc. Examples of the polydialkylsiloxanediamine include polydimethylsiloxane-diamine, polymethylethyl-siloxanediamine, etc. Examples of the polydialkyl-siloxanemonoamine include poly-dimethylsiloxane-monoamine, polymethylethylsiloxane-monomaine, etc.
Examples of the polysiloxane compound include a type wherein an OH group is introduced at both ends, a type wherein an NH2 group is introduced at both ends, a type wherein an OH group is introduced at one end and a type wherein an NH2 group is introduced at one end. When using the type wherein an OH group is introduced at both ends or a type wherein an NH2 group is introduced at both ends, an amphoteric urethane resin having polysiloxane bond(s) in a principal chain is obtained. When using the type wherein an OH group is introduced at one end or a type wherein an NH2 group is introduced at one end, an amphoteric urethane resin having polysiloxane bond(s) at its side chain(s) or end(s) is obtained.
In the cosmetics of the present invention, the amphoteric urethane resin is preferably used in the form of an aqueous solution. In the present invention, the aqueous solution includes not only an aqueous solution state where the amphoteric urethane resin is completely dissolved in water but also a water dispersion state where the amphoteric urethane resin is dispersed in water.
It is also possible to add a crosslinking agent such as silane coupling agent to the water dispersion of the above amphoteric resin, thereby to provide the crosslinkability. To provide the storage stability, various additives may be added and examples thereof include protective colloidal agents, bactericides, mildewproofing agents, etc.
The silicone polymer used together with the said amphoteric urethane resin is not specifically limited as far as it has polysiloxane bond(s) in a molecule and can be used in cosmetics, and examples thereof include silicone resin, silicone oil, silicone emulsion, silicone rubber, etc. Examples of the silicone rubber include nonionic, polyether-modified, phenyl-modified, amino-modified, alkyl-modified, alkoxy-modified, cyclic silicone polymers, etc. These silicone polymers can be used alone or in combination.
Examples of the nonionic silicone polymer includes those represented by the following general formula (1):
[wherein R represents a hydrogen atom, hydrocarbon group(s) having 1 to 12 carbon atoms, or xe2x80x94OSi(CH3)3 and may be the same or different; and n represents a numeral of 3 or more].
In the general formula (1), the hydrocarbon group(s) having 1 to 12 carbon atoms is are straight-chain or branched-chain saturated hydrocarbon group(s) and is/are preferably methyl group(s), while n is preferably from 50 to 3000.
Examples of the nonionic silicone polymer represented by the general formula (1)include methyl polysiloxane whose R is entirely methyl group(s).
Examples of the polyether-modified silicone polymer includes those represented by the following general formula (2). Each repeating unit in the silicone polymer of the present invention may be in any form of polymerization such as random polymerization and block polymerization.
[wherein R represents hydrocarbon group(s) having 1 to 12 carbon atoms or group(s) represented by the following general formula (2xe2x80x2) and may be the same or different, provided that at least one of R(s) is group(s) represented by the following general formula (2xe2x80x2); m represents 0 or a numeral of 1 or more; and n represents a numeral of 1 or more]
(wherein Rxe2x80x2 represents a hydrogen atom or hydrocarbon group(s) having 1 to 10 carbon atoms; a represents a numeral of 1 to 10; b represents a numeral of 1 to 300; and c represents a numeral of 0 to 300)
In the general formula (2), the hydrocarbon group(s) having 1 to 12 carbon atoms represented by R include(s) a straight-chain or branched-chain saturated hydrocarbon group(s), m is preferably from 10 to 500, and n is preferably from 1 to 500. In the general formula (2xe2x80x2), a is preferably 2 to 4, b is preferably from 2 to 50, and c is preferably from 0 to 5.
Examples of the phenyl-modified silicone polymer includes those represented by the following general formula (3):
[wherein R represents hydrocarbon group(s) having 1 to 12 carbon atoms, xe2x80x94OSi(CH3)3 or phenyl group(s) and may be the same or different, provided that at least one of R(s) is phenyl group(s); m represents 0 or a numeral of 1 or more; and n represents a numeral of 1 or more].
In the general formula (3), the hydrocarbon group(s) having 1 to 12 carbon atoms represented by R include(s) straight-chain or branched-chain saturated hydrocarbon group(s), m is preferably from 0 to 500, and n is preferably from 1 to 2000.
As the phenyl-modified silicone polymer represented by the general formula (3) methylphenyl polysiloxane is preferably used.
Examples of the amino-modified silicone polymer includes those represented by the following general formula (4):
[wherein R represents a hydrogen atom, hydrocarbon group(s) having 1 to 12 carbon atoms, hydroxyl group(s), methoxy group(s) or group(s) represented by the following general formula (4xe2x80x2) or (4xe2x80x3) and may be the same or different, provided that at least one of R(s) is group(s) represented by the following general formula (4xe2x80x2) or (4xe2x80x3); m represents 0 or a numeral of 1 or more; and n represents a numeral of 1 or more
[wherein Rxe2x80x2 represents a hydrogen atom or hydrocarbon group(s) having 1 to 6 carbon atoms and may be the same or different; Z represents a halogen ion or an organic anion; a represents a numeral of 1 to 6; b represents a numeral of 0 to 6; and c represents a numeral of 0 to 6)].
In the general formula (4), the hydrocarbon group(s) having 1 to 12 carbon atoms represented by R include(s) straight-chain or branched-chain saturated hydrocarbon group(s), m is preferably from 3 to 500, and n is preferably from 1 to 500. In the general formulas (4xe2x80x2) and (4xe2x80x3), the hydrocarbon group(s) having 1 to 6 carbon atoms represented by Rxe2x80x2 include(s) straight-chain or branched-chain saturated hydrocarbon group(s).
As the amino-modified silicone polymer represented by the said general formula (4), aminodimethycone represented by the following structural formula is preferably used.
[wherein m and n are as defined in the general formula (4)]
Examples of the alkyl-modified silicone polymer include, those represented by the following general formula (5):
[wherein R represents hydrocarbon group(s) having 1 to 50 carbon atoms and may be the same or different, provided that at least one of R(s) is hydrocarbon group(s) having 12 to 50 carbon atoms; m represents 0 or a numeral of 1 or more; and n represents a numeral of 1 or more].
In the general formula (5), the hydrocarbon group(s) having 1 to 50 carbon atoms represented by R include(s) straight-chain or branched-chain saturated hydrocarbon group(s), and hydrocarbon group(s) having. 12 to 50 carbon atoms is/are preferably used, and hydrocarbon group(s) having 15 to 40 carbon atoms is/are more preferably used. m is preferably from 10 to 500, and n is preferably from 10 to 500.
Examples of the alkoxy-modified silicone polymer include those represented by the following general formula (6):
[wherein R represents hydrocarbon group(s) having 1 to 12 carbon atoms or alkoxy group(s) having 1 to 50 carbon atoms and may be the same or different, provided that at least one of R(s) is alkoxy group(s) having 1 to 50 carbon atoms m represents 0 or a numeral of 1 or more, and n represents a numeral of 1 or more].
In the general formula (6), the hydrocarbon group(s) having 1 to 12 carbon atoms represented by R include(s) straight-chain or branched-chain saturated hydrocarbon group(s). The alkoxy group(s) having 1 to 50 carbon atoms represented by R include(s) straight-chain or branched-chain saturated alkoxy group(s) and alkoxy group(s) having 1 to 20 carbon atoms is/are preferably used. m is preferably from 3 to 500, and n is preferably from 1 to 100.
Examples of the cyclic silicone polymer includes those represented by the following general formula (7):
[wherein R represents hydrocarbon group(s) having 1 to 12 carbon atoms and may be the same or different in each repeating unit; m represents 0 or a numeral of 1 or more; n represents a numeral of 1 or more; and m+n is from 4 to 10].
In the general formula (7), the hydrocarbon group(s) having 1 to 12 carbon atoms represented by R include(s) straight-chain or branched-chain saturated hydrocarbon group(s).
The average molecular weight of these silicone polymers is preferably within a range from 100 to 10,000,000, and particularly preferably from 10,000 to 1,000,000.
The silicone polymer is preferably used in the form of an aqueous solution or a water dispersion in view of the stability for cosmetics
The incorporation ratio of the amphoteric urethane resin to the silicone polymer is preferably within a range from 0.1/100 to 100/0.01, and particularly preferably from 100/0.01 to 100/5, in terms of a weight ratio.
Furthermore, any components used commonly in cosmetics such as pigments, coloring matters, colorants, perfumes, surfactants, humectants, preservatives, antiseptics, bactericides, antioxidants, oil agents, viscosity modifier and ultraviolet absorbers can be contained in the cosmetic of the present invention, in addition to the amphoteric urethane resin and silicone polymer.
The cosmetics of the present invention can be prepared, for example, by the following methods.
Preparation of Hair Cosmetics (Foam Hair Fixatives)
In the aqueous solution of the amphoteric urethane resin thus obtained described above, a silicone polymer, various surfactants such as polyoxyethylena alkyl ether, and coconut oil fatty acid diethanolamide, ethanol, deionized water, etc. are blended in the predetermined proportion, and mixed until they are made homogenous to obtain a component X. Then, a component Y made of a propellant (LPG) is added to prepare a desired foam hair fixative.
Preparation of Hair Cosmetics (Aerosol Spray Hair Fixatives)
In the aqueous solution of the above amphoteric urethane resin, a silicone polymer, deionized water, sodium dioctyl sulfosuccinate, ethanol, etc. are blended in the predetermined proportion, and mixed until they are made homogenous to obtain a component X. Then, a component Y made of a propellant (LPG) is added to prepare a desired aerosol spray hair fixative.
Preparation of Hair Cosmetics (Gel-like Hair Fixatives)
First, a viscosity modifier, triethanolamine, ethanol, deionized water, etc. are blended in the predetermined proportion, and then mixed until a viscous gel is formed to obtain a component X. Then, a silicone polymer, ethanol, deionized water, etc. are blended in the aqueous solution of the amphoteric urethane resin in the predetermined proportion to obtain a component Y. The resulting component Y is added to the above component, and mixed until they are made homogenous to prepare a desired gel-like hair fixative.
Preparation of Hair Cosmetics (Pump Spray Hair Fixatives
In the aqueous solution of the amphoteric urethane resin, a silicone polymer, sodium dioctyl sulfosuccinate, ethanol, deionized water, etc. are blended in the predetermined proportion, and mixed until they are made homogenous to prepare a desired pump spray hair fixative.
Furthermore, skin care cosmetics such as shaving cream, skin care lotion and sunscreen lotion; and make-up cosmetics such as nail polish, mascara and foundation can be prepared according to the general preparation methods of these cosmetics.

Cosmetic compositions containing amphoteric polyurethanes

National Starch and Chemical Investment Holding Corporation


Provided are a propulsion device for a ship and a ship including the same. The propulsion device for the ship includes: a rear propeller fixed to a rotation shaft; a front propeller that is rotatably supported on the rotation shaft in the front of the rear propeller; at least one bearing interposed in at least one of spaces between a hub of the front propeller and the rotation shaft and between the rotation shaft and a ship body; and an inverse rotation unit that inverts rotation of the rotation shaft, transfers the inverted rotation to the front propeller and includes a gearbox that is accommodated in an installation space formed in a tail of the ship body in a state in which a plurality of gears for implementing inversion of the front propeller are embedded, wherein at least one measurement unit for measuring operating states of the at least one bearing is mounted to the rotation shaft.

Conventional propulsion devices for ships each include one spiral propeller. However, a propulsion device having one propeller cannot use rotation energy of a waster current caused by rotation of the propeller as a propulsive force and thus has a large energy loss.
A counter rotating propeller (CRP) may recover the rotation energy that is lost in this way as the propulsive force. In the CRP, two propellers installed in the same axial line generate the propulsive force while being rotated in opposite directions. Rotation energy of a fluid that passes through a front propeller is recovered by a rear propeller while the rear propeller is rotated in a reverse direction. Thus, the CRP may have excellent propulsion performance compared to the propulsion device having one propeller.
However, since the CRP includes an inverse rotation unit that implements opposite rotation of two propeller and a hollow shaft, it is relatively difficult to manufacture and install the CRP, and a high technology level is required so that the CRP operates stably while maintaining reliability.
U.S. Patent Laid-open Publication No. US2011/0033296 (published on Feb. 10, 2011) and Japanese Patent Laid-open Publication No. S62-279189 (published on Dec. 4, 1987) each disclose an example of the above-described CRP. U.S. Patent Laid-open Publication No. US2011/0033296 discloses a CRP having an epicyclic gear type inverse rotation unit and a hollow shaft, and Japanese Patent Laid-open Publication No. S62-279189 discloses a CRP in which an epicyclic gear type inverse rotation unit is installed at an end of a ship.

Propulsion apparatus for ship and ship having the same


A connection component suitable for use with an enteral fluid delivery set wherein the connection component consists of a threaded cap having a projecting spike thereon to penetrate and deform a foil diaphragm on the fluid container and further including an air passageway having a flexible member therein to allow filtered air to flow into the fluid container while preventing the flow of fluid from the fluid container through the air passageway.

In an enteral fluid delivery system for a patient, there is a need to provide a connecting component which will effect a quick connection of the fluid delivery set to a prefilled, foil-sealed container containing enteral fluid. In these fluid delivery systems, the connecting component is preferably a cap, which replaces the shipping cap on the prefilled container when the container is connected to the fluid delivery set for administration of the enteral fluid to the patient. The connecting component preferably includes a means for perforating the foil diaphragm on the container during attachment of the fluid delivery set to the container to simplify the assembly of the delivery system. It is further desireable that the connecting component provide a means to allow air to vent into the container as the enteral fluid flows from the container. This venting means should be designed to allow filtered air to flow into the container while preventing the air from flowing into and through the fluid passageway. Additionally, the venting means must prevent the passage of enteral fluid from the container through the air passageway.
One approach is illustrated in U.S. Pat. No. 3,542,240, issued to Solowey on Nov. 24, 1970. The first embodiment of Solowey illustrates the use of a single, centrally positioned projection designed to puncture the diaphragm of the container. The projection includes parallel air and liquid passageways therein to allow vented air to flow into the container while the fluid is administered to the patient. Additionally, Solowey illustrates the use of a check valve consisting of a steel ball and coil spring moveably positioned within the air passageway. Finally, the Solowey device includes a circular flange on the bottle which engages a flexible sleeve on the cap to prevent the removal of the cap during the operation of the administration set. Another embodiment of Solowey illustrates the use of a pair of parallel, spaced apart air and liquid passageways therein.
The present invention seeks to provide a connection component for effecting a quick and reliable coupling between the fluid delivery set and the prefilled, sealed container. The present invention minimizes the potential for contamination of the container by providing an efficient means for puncturing the foil diaphragm of the container while simultaneously tearing the diaphragm to create a passageway therein to allow for the flow of vented filtered air therethrough.


A combination patch panel and distribution amplifier within a single housing composed of a plurality of card modules which may have a data format interface with a configurable input/output module known as small footprint plugables for the transmission and distribution of signals, data, and the like, in either serial digital mode, internet protocol mode or other signals, each card module configurable to provide for any front panel jack functioning as a repeater output from external source, input distribution amplifier, output distribution amplifier, or destination jack.

1. Field of the Invention
The present invention relates to a patch panel system of multiple card modules, each of which incorporate an input repeater circuit and distribution amplifier, and a configurable input/output module for the patching of audio, video, data, recording, broadcasting, and telecommunication lines, the panel able to patch not only serial digital transmissions, but also packet information transmitted by means of fiber optic, internet protocol and others via a data format interface or small footprint pluggable (SFP).
2. Description of the Prior Art
Jack panels or patch panels are well-known in the broadcasting, telecommunication and other audio and video industries where they are used extensively to provide flexibility in the interconnection of audio, video or data circuits. By employing a patch panel, various circuits can be connected together temporarily using one or more patch cords provided with plugs that are received in a plurality of jacks mounted in the panel of the patch panel. In a typical installation, a plurality of patch panels would be utilized with each patch panel having a plurality of input wires and output wires secured thereto and connected to an article of electrical equipment be it a telephone, video monitor, computer, computer monitor or the like. The distribution of the signals further required a plurality of wires interconnecting the patch panels with distribution amplifiers to insure the quality of the signal as it is directed between the various desired electrical equipment. This requirement of interconnecting the patch panels with a plurality of distribution amplifiers increases the cost of installing a facility where audio, video and data transmission and interconnection is required and further increases the cost of maintaining such a system. Applicant addressed the problem and developed a solution as evidenced by U.S. Pat. No. 6,078,507.
Applicant now has further developed the patch panel with incorporated distribution amplifiers to include a data format interface and a configurable input/output module with each card module which allow the patch panel to handle transmitted coaxial cable transmissions which essentially are serial digital as well as handle those transmissions which are being developed and utilize the fiber optic, internet protocol and others for transmission. The configurable input/output module is also known as a small footprint pluggable or SFP.

Patch panel and distribution amplifier with configurable input/output module


This invention relates to a component door assembly for an electronic device which hides and protects removable electronic components. The door has separate locking and moving mechanisms so that two operations must be performed before the door can be opened. Specifically, in the preferred embodiment a resilient sliding door is mounted on tracks or grooves in the housing of an electronic device. The door has a button on one end and a handle on the other end. To open the door, the button is pressed inward while the handle is pulled in the direction of the button.

This invention relates generally to latches for sliding doors and in particular for sliding doors on computer equipment.
Electronic devices typically have components which may be removed and replaced in the normal course of the device's operation. The housings for these devices must therefore provide the user easy access to the removable components. This invention is directed to a method and apparatus for providing access to electronic equipment components.


Free electrons laser with gaseous medium wiggler and method to use this laser. The laser includes a chamber (22) designed to be traversed by a beam of previously accelerated electrons, a wiggler (44) which creates in this chamber a periodic magnetic field interacting with the beam of electrons, and means (54) to fill the chamber with a gas formed of atoms or molecules having at least one resonance line at a determined frequency. The laser is tuned on this resonance line, which enables the laser to produce a frequency light close to this determined frequency.

It is known that a free electron laser is a high efficiency wavelength-tunable laser and is able to emit a high-powered electromagnetic radiation and, to this effect, uses the characteristic feature of a beam of relativistic electrons to emit a coherent electromagnetic radiation when it is subjected to a static yet spatially periodic magnetic field generated by a device known as a wiggler.
Such a laser may be an amplifier and function without any optical cavity, or an oscillator in which an optical cavity is required so as to trap the radiation emitted by the beam of relativistic electrons.
Various free electron lasers are described in an article (1) by C. W. Robertson and al. and entitled "A review of free electron lasers" and published in the Physics of fluids journal, B1, January 1989.
Existing free electron lasers have the drawback of requiring beams of electrons with extremely high energy and thus expensive accelerators and thick protection devices so as to obtain electromagnetic radiations with short wavelengths.
There is also an existing free electrons laser disclosed by an article (2) by R. H. Pantell and al, Journal of the optical society of America B: optical physics, vol. 6, No. 5, May 1989, p. 1008 to 1014 and by an article (3) by M. B. Reid and al., IEEE Journal of quantum electronics, vol. 5, No. 1, Jan. 1989, p. 84 to 87, these articles to be referred to subsequently, the tuning condition of this free electrons laser being modified by introducing a gas into the wiggler of the laser.
However, a considerable modification of the tuning condition requires high gas pressure, which results in the wiggler having to be materially separated from the pipe linking the latter to the electrons accelerator associated with the laser.

Free electron laser with a gaseous medium wiggler and method to use this laser


A cleaning device for a photosensitive drum includes a cleaning roller, a cleaning blade, and a layer control member. The layer control member may include an upstream scraper having a surface that surface contacts the cleaning roller in a substantially same direction as a rotation direction of the cleaning roller. In addition, the layer control member may include a downstream scraper having an edge that contacts the cleaning roller. The downstream scraper may be positioned downstream of the contact position between the cleaning roller and the upstream scraper in the rotation direction of the cleaning roller. In some embodiments, the downstream scraper edge may line contact the cleaning roller in a direction opposing the rotation direction of the cleaning roller.

In an image forming apparatus with an electrophotographic system, a charging unit electrically charges a photosensitive drum in advance, and an exposure unit emits light on a surface of the photosensitive drum. Then, an electrostatic latent image is formed on the surface of the photosensitive drum. A developing unit bears toner. The toner adheres to the electrostatic latent image to form a toner image. The toner image is transferred on and fixed to a sheet.
After the toner is transferred on the sheet, a small quantity of the toner may not be transferred and remain on the surface of the photosensitive drum. The remaining toner may affect the formation of the next image(s). Therefore, a device that cleans the surface of the photosensitive drum has been utilized.
More specifically, a cleaning roller and a cleaning blade may be used to contact the surface of the photosensitive drum. The toner contains a very small quantity of an external additive. The cleaning roller uses the toner containing the external additive to remove substances, such as corona discharge products adhering to the surface of the photosensitive drum.
Also, a scraper contacts the cleaning roller. The scraper controls the thickness of a layer of the toner being held on the cleaning roller. If the thickness of the layer of the toner is uneven, a smaller-thickness portion of the layer of the toner may not effectively polish the surface of the photosensitive drum. In contrast, in a larger-thickness portion of the layer of the toner, the electric charge of the toner is hardly discharged, and the photosensitive drum may be electrostatically damaged. Unfortunately, the above mentioned conventional structure still has a problem in providing for a proper quantity of the remaining toner adhering to and being held by the cleaning roller.
This is because the scraper only line contacts the cleaning roller in a counter direction with respect to a rotation direction of the cleaning roller. In other words, the scraper contacts the cleaning roller only by point contact in a sectional view along a plane substantially orthogonal to a rotation axis of the cleaning roller. Hence, most of the remaining toner is scraped away from the cleaning roller and is hardly held by the cleaning roller.
In this state, it is difficult to continuously and effectively polish the surface of the photosensitive drum. Also, the external additive in the toner may adhere to the surface of the photosensitive drum, be separated from the surface of the photosensitive drum, and contaminate the charging unit.

Cleaning device for photosensitive drum and image forming apparatus equipped with cleaning device


Semi-submersible floating decanters and methods of use are provided. The decanters are moveable between a non-decant position and a decant position, and include a float forming an internal cavity, the float having a central annulus, a weir having an inlet opening and positioned within the center of the annulus and fixedly connected to the float forming a passage between the float and the weir, and a discharge conduit connected to the weir for discharging a supernatant fluid therefrom. A depth adjusting mechanism is provided for moving the decanter within a liquid between a non-decant position wherein the inlet opening is above the surface of the liquid and a decant position wherein the inlet opening is positioned within the supernatant to allow the supernatant to be withdrawn, the depth adjusting mechanism including a pumping mechanism for moving a fluid relative to the internal cavity.

1. Technical Field
The present invention relates in general to waste material treatment and more particularly to a decanting apparatus and methods for removal of a supernatant from a vessel, such as a sequential batch reactor.
2. Background Art
In a sequencing batch reactor process of wastewater treatment a reactor is operated in a batch treatment mode involving a fill phase, aerate or react phase, a settle phase and a decant phase. During the aerate phase the wastewater influent is mixed and aerated. In the settle phase the suspended solids are allowed to settle typically forming a scum surface, a layer of supernatant, and a sludge blanket. In the decant phase the relatively clear supernatant is removed without drawing solids from the scum layer or sludge blanket. When in a non-decant phase it is necessary to prevent accumulation of suspended solids in the decanter that will contaminate the supernatant that is drawn in to the weir in the decant phase.
The quality of the withdrawn supernatant is affected by the design of the decanter. If during the decant phase the decanter draws in floating solids form the scum layer or material form the sludge blanket the quality of the discharged supernatant will be unacceptable as a discharge effluent. Further, if suspended solids enter the weir of the decanter during the non-decant phases of the process the solids will be discharged with the supernatant during the decant phase adversely affecting the quality of the discharged supernatant.
The prior art decanters are generally classified as fixed decanters or floating decanters. An example of a fixed type decanter is disclosed in U.S. Pat. No. 4,596,658. The fixed decanter remains under the surface of the mixed liquor wherein suspended solids may settle in the weir. It is attempted to prevent solids form settling in the weir by maintaining the solids in a laminar flow inlet. However, it is common for solids to settle in the decanter weir and be discharged with the decanted supernatant. The fixed decanter design has numerous other drawbacks. For example, the fixed decanter design requires expensive installation and precise management of the sequencing batch reactor process to work properly.
Floating decanters attempt to prevent solids or scum from entering the weir and the stream of decanted supernatant by use of a float. An example of a floating type decanter is disclosed in U.S. Pat, No. 4,695,376. The floating decanter of the 376 patent attempts to prevent suspended solids from entering the weir during the non-decant phases by sealing the weir against the float. After the settle phase, a linear actuator is utilized to lower the weir for the underside of the float thereby enabling the weir to decant the supernatant.
One drawback of the floating decanter disclosed in the 376 patent is that during the non-decant phases the suspended solids enter and accumulate in the weir due to the inability of the device to form an absolute seal. The accumulation of solids in the decanter during the non-decant phases contaminates the supernatant discharged during the decant phase. This contamination of the supernatant results in the rejection of the discharged effluent, thus requiring flushing of the lines before resuming withdrawal of the supernatant. This floating decanter further includes guideposts or moorings, extending from the bottom of the reactor, to maintain the floating decanter in a selected location and stable in the fluid.
Another example of a floating type decanter is disclosed in U.S. Pat. No. 5,104,528. This floating decanter includes a weir disposed within the annulus of a float. A linear actuator is connected between the weir and the float. During the non-decant phases the weir is maintained in a position above the surface of the liquor. After the settle phase is completed the linear actuator is activated to lower the weir to a position below the liquid surface. The decant phase is ended by raising the weir to a position above the surface of the liquid. This prior art floating decanter includes guides posts extending from the bottom of the reactor to maintain the floating decanter in a set location and maintain stability of the decanter in the liquid.
It is a desire to provide a semi-submersible floating decanter that overcomes the drawbacks of the prior art decanters. It is a further desire to provide a semi-submersible floating decanter that is able to deliver the supernatant without contamination with solids, is simple, inexpensive, requires minimal maintenance, and is failsafe.

Semi-submersible floating decanters and methods of using same