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Soy Protein Preparations as Antispattering Agents for Margarine It was found that soy protein concentrates obtained by successive extraction of ground soybeans with hexane and ethanol or with hexane alone, grinding to a particle size less than 100 μ and subsequent leaching with diluted acids at pH 4.5, are good antispattering agents. If the process is preceded by a debittering treatment of the beans with steam, products having very neutral taste are obtained. Addition of 0.2% of these concentrates to fully deaerated margarine containing 5% milk and 0.15% each of mono- plus diglycerides and lecithin, prevents spattering completely. Half-fat margarine does not spatter inspite of its high water content, if 0.1% of the concentrate is added. A disadvantage is the infection of soy protein concentrates with resistent fungus, which necessitates sterilization of the proteins at 85% C in acidic medium.  相似文献   

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The resin-based ion exchange materials used nowadays are insoluble polyelectrolytes. Synthetic processes allow a large variety of modifications of the ion exchange substance itself as well as of the functional groups. It is thus possible to offer tailormade special resins for many different uses. Beside resins which are resistant at elevated temperatures or in oxidizing media, the introduction of the macroporous matrix has proved to be a special success. It leads to more resistant products and makes it possible to use appropriately designed ion exchange resins for general adsorption purposes as well, similar to activated carbon. The range of application of ion exchange resins is rapidly increasing as new resins are being offered and improved process engineering is being developed. The most important fields are water conditioning, detoxification of waste waters, recovery of valuable inorganic and organic substances, as well as use in chemical processes. These versatile products will in future be used in these fields to a greater extent and new applications will certainly be found.  相似文献   

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Fibres made from poly(acrylonitrile-co-methylacrylate-co-itaconic acid) were stretched under different conditions. The overall degree of orientation as well as the degree of orientation and amount of the paracrystalline regions were evaluated; mechanical properties were investigated. The correlation between the values obtained and the so-called compensation tension of the fibres leads to the conclusion that the latter is a measure for the inner tension of the fibres and renders possible improvements in preparation and processing of the fibres.  相似文献   

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By copolymerization of ethylene-dimethacrylate with acrylonitrile and glycidylmethacrylate, respectively, reactive microgels with diameters of approx. 50nm were obtained. Modification reactions led to functional groups (imidate or aldehyde groups) suitable for covalent enzyme coupling. When immobilizing the enzymes lactate dehydrogenase, alkaline phosphatase and proteinase K it was found that the residual activity of these conjugates was very much higher compared with conventional porous supports due to the absence of diffusional restrictance.  相似文献   

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Acetoacetaldehyde Dimethylacetal as a Starting Material for Syntheses The use of acetoacetaldehyde dimethylacetal (1) leads to the introduction of the group \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm =}\mathop {\rm C}\limits^{\mathop |\limits^{{\rm CH}_{\rm 2}}} ---{\rm CH}_{\rm 2} ---{\rm CH(OCH}_{\rm 3} {\rm)}_{\rm 2} $\end{document} by reaction at the carbonyl carbon atom, and of the group CH3–CO–CH2–CH?or CH3–CO–CH?CH– by reaction at the acetalic carbon atom. For synthetic purposes it is important that methanol can be splitten off from 1, and the acetoacetaldehyde enol ether methoxybutenone (2) is generated. With catalytic amounts of acids or bases an equilibrium mixture with 70% 1 and 30% 2 is formed; 2 shows the higher reactivity of a vinylogous acetic ester. 1 as well as 2 can be attacked at each of the four carbon atoms; ring closure reactions were observed with the carbon atom 2 or 4 alone, or with two carbon atoms (6 possibilities, prevalent 2 + 4), and occasionally by participation of two molecules of 1 or 2.  相似文献   

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Engineering design data for agitator vessels as fermentors . The article develops and collects design data for stirring vessels for calculation of mass and heat transfer and the flooding point and stirrer power requirements for aerated liquids. The data refer to low-viscosity, higher viscosity, and structure viscosity liquids with difering coalescence behaviour. The working data presented are used to derive results for a specific system (air/aqueous solution of carboxymethylcellulose) which illustrate decisive relationships and limitations arising from mass and heat transfer. There results important information for the operation, and choice, and scale-up of stirred fermentors.  相似文献   

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Phenyl-Mercuric Compounds as Preservatives for Cosmetics 0.005 to 0.01% phenyl-mercuric salts are adequate for the preservation of cosmetics. According to the literature this preservative action is almost completely neutralized by compounds containing SH-groups, whereas the experiments carried out by the author showed that 2% solutions of degraded horn keratin at pH 8 can be preserved with 0.01 to 0.005% phenyl mercuriacetate. Addition of 0.3% sodium lauryl sulphate improved the action. Sensitivity tests carried out on 12 persons who were hypersensitive to mercury showed positive reactions only in two cases.  相似文献   

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Meeting future energy demands with more efficient, lower emission, and safe energy technologies has top priority in the medium term. Consumer-friendly energy concepts, integrated into regional and supraregional energy supply structures, represent further elements. These will make important contributions to resource-conserving and environmentally compatible power supplies utilizing local energy sources including renewable resources. Supplying energy to large areas involves additional tasks, from compensation of large amounts of fluctuating energy to the transport of fluctuating energy to the transport of renewable energy over long distances. Solar dish, parabolic section, and tower power generating plant have considerable economic and CO2-reduction potential in sunny countries, such as in the Mediterranean region, However, the costs of solar-thermal electricity generation have to be reduced by a factor of 1.5 to 2. Fuel cell systems can attain particular significance as efficient low-emission energy conversion systems in power plant and automative engineering once their technical and economic potential can be realized.  相似文献   

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Silicone as Raw Material for Foaming and Anti-Foaming Agents The remarkable significance of methyl polysiloxanes in the field of anti-foaming agents is based on two fundamental principles, namely, low intermolecular interactions (low surface tension), and the unique variability of the polymer system which permits that by variation of molecular weight, molecular weight distribution as well as the nature and number of end groups, these agents can be made to fit into a particular type of application. The above properties have also led to the use of modified methyl siloxanes as foam stabilizers. In the latter case, a further factor enhancing the efficacy by the introduction of a solubilizing group in the modified siloxane is made use of. Examples for the same are polyether modified methyl polysiloxanes as foam stabilizers in polyurethane foams, and anionactive methyl siloxanes containing sulfate groups as foaming agents in fire extinguishing systems.  相似文献   

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Synthesis of Short-Chained Alkanesulfonic Acids as Additives in Industrial Cleaners Short-chained alkanesulfonic acids are useful additives in industrial cleaners because they are able to remove both organic as well as mineral residues. Because of their high acidity and the low foam formation they are discussed as substitutes of phosphoric acid in acidic cleaners. A production process of ethane-, propane- and butane sulfonic acid was developed on the base of the olefins ethene, propene and 1-butene. In a first step the olefin reacts with ammonium bisulfite in a radical reaction to yield the ammonium sulfonate. In the second step the alkanesulfonic acids are formed by acidification of the sulfonates with concentrated hydrochloric acid.  相似文献   

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At the moment PMMA and PC are generally used as substrates for ROM optical discs. In several cases inorganic glass is preferred for DRAW and E-DRAW information carriers especially because of its high-barrier characteristics. The benefit of PMMA having low sensitivity to orientation birefringence is opposed by the disadvantage of high water absorption causing warp. It is just the inverse situation with PC. So a polymer material would be desirable which exhibits low optical anisotropy and simultaneously reduced water absorption. The anisotropy problem could possibly be solved regarding additivity of bond polarizabilities within the monomer units, i. e. compensating positive and negative anisotropies by copolymerisation or blending. Reduced water absorption means avoiding polar groups. Polymers are scarcely real barriers against O2 and H2O vapor compared to metals and inorganic glass. PAN and PVDC could be relatively effective as thin layers.  相似文献   

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Medium-Chain Triglycerides as Fat Stock for Margarine Under the following conditions, a spreadable margarine on MCT basis having long keepability and very good organoleptic behaviour, can be produced: 1. The C10-fatty acid fraction in the mixture of MCT fatty acids, before esterification, must lie between ca. 82-89%. 2. The MCT-fat produced from the above mixture must have a tricaprin content of ca. 50-70% and a slip point of ca. 24deg;-27° C. 3. During the production of margarine, care must be taken to assure a nearly complete crystallisation and a rapid transformation of the β′-crystal form to the stable ß-modification. Moreover, an adequate mechanical treatment is necessary for comminution of the crystals after crystallisation. This is decisive for a broad spreadability range of the product.  相似文献   

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In the present work oxygen index (OI) measurements and thermogravimetric analysis (TG) for a series of polyurethanes based on diols and isocyanate were conducted. It was found that a correlation exists between some of the thermal degradation parameters obtained from TG and OI-values. Analysis of experimental results confirms that the amount of mass loss at 250°C is directly proportional to the OI-value. It was also found that the logarithmic temperatures of maximal decomposition rates are directly proportional to the OI-values.  相似文献   

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