63 research outputs found
Experimental Evaluation of Application of Cross-Flow Ultrafiltarion Method for O Antigen Concentrating in Cholera Chemical Bivalent Vaccine Production
Demonstrated is possibility to apply cross-flow ultrafiltration method for O antigen of Vibrio cholerae M-41 Ogawa concentrating from germ-free centrifugate. Technological process of concentrating was optimized. Worked out were the regimes of conservation and cleaning of the ultrafiltration device. The prospects of cross-flow ultrafiltration method introduction in technology of cholera chemical bivalent vaccine production were determined
Влияние активирующих добавок на процесс холодного спекания высокоэнтропийной керамики (MnFeCoNiCu)3O4
Objectives. To obtain experimental data on the effect of activating additive type on the cold sintering process of (MnFeCoNiCu)3O4 high-entropy ceramic. The following substances were used as activating additives: ammonium acetate (CH3COONH4), acetic acid (CH3COOH), ammonium chloride (NH4Cl), potassium fluoride dihydrate (КF·2H2O), lithium fluoride (LiF), sodium fluoride (NaF), and sodium hydroxide (NaOH).Methods. Synthesis of the initial powder by low-temperature self-propagating method; investigation of the powder particles size distribution by laser diffraction method; analysis of the particle shape and compacted sample microstructure by scanning electron microscopy; investigation of the phase composition by X-ray phase analysis; high-entropy ceramic sample consolidation by cold sintering process. The density of the initial powder and the relative density of cold sintered samples were determined by the Archimedes method.Results. Samples with a relative density of over 0.70 were obtained using distilled water, CH3COONH4 and NaOH during cold sintering at 300 °C, with a holding time of 30 min and pressure 315 MPa.Conclusions. For the first time, the effect of the type of activating additive on the relative density of high-entropy ceramics (MnFeCoNiCu)3O4 samples obtained by cold sintering process has been experimentally demonstrated. The samples microstructures have pronounced differences: 20 wt % distilled water does not lead to grain growth, with only their compaction to 0.71 relative density observed; however, the addition of 0.1 wt % CH3COONH4 and NaOH increases the average grain size when reaching similar relative densities (0.70 and 0.71, respectively). X-ray diffraction analysis showed that the cold sintering process does not lead to a change in the phase composition of the initial (MnFeCoNiCu)3O4 powder, confirming the preservation of the high-entropy structure.Цели. Получение экспериментальных данных о влиянии вида активирующей добавки на процесс холодного спекания высокоэнтропийной керамики состава (MnFeCoNiCu)3O4. В качестве активирующих добавок были использованы: ацетат аммония (CH3COONH4), уксусная кислота (CH3COOH), аммоний хлористый (NH4Cl), калий фтористый 2-х водный (КF·2H2O), литий фтористый (LiF), натрий фтористый (NaF), гидроксид натрия (NaOH).Методы. Синтез исходного порошка методом низкотемпературного самораспространяющегося синтеза; исследование гранулометрического состава порошка методом лазерной дифракции; анализ формы частиц и микроструктуры скомпактированных образцов методом сканирующей электронной микроскопии; анализ фазового состава методом рентгенофазового анализа; консолидация образцов высокоэнтропийной керамики методом холодного спекания; плотность исходного порошка и относительная плотность образцов керамики холодного спекания определялись методом Архимеда.Результаты. Образцы с относительной плотностью свыше 0.70 получены с применением дистиллированной воды, CH3COONH4 и NaOH в процессе холодного спекания при температуре 300 °С, времени выдержки 30 мин и давлении прессования 315 МПа.Выводы. Впервые экспериментально показано влияние вида активирующей добавки на относительную плотность образцов высокоэнтропийной керамики (MnFeCoNiCu)3O4, полученных с помощью процесса холодного спекания. Микроструктуры образцов имеют выраженные отличия: 20 мас. % дистиллированной воды не приводит к росту зерен, наблюдается только их уплотнение до 0.71 относительной плотности; при добавлении 0.1 мас. % CH3COONH4 и NaOH наблюдается рост среднего размера зерен при достижении близких показателей относительной плотности (0.70 и 0.71 соответственно). Рентгенодифракционный анализ показал, что процесс холодного спекания порошка (MnFeCoNiCu)3O4 не приводит к изменению фазового состава исходного порошка, что свидетельствует о сохранении высокоэнтропийной структуры
Non-Waste Alternative Technologies in the Production of Heterologous Anti-Rabies Immunoglobulin
Presented is a comprehensive approach to utilization of the wastes that appear in the process of heterologous anti-rabies immunoglobulin production (packed red cells, fibrin, and alcohol-containing products). Specific immunoglobulin is extracted from the surface of red blood cells using desorption technique. Additional yields of immunoglobulin after exposure of erythrocytes to non-ionic detergent amount to 10-19 % of the output. Rich protein supplement feeding for horses-producers is obtained from spray-dried packed red cells. Solid nutritious substrate for microbiological media production is obtained from fibrin using enzymic hydrolysis method. The efficiency of the fibrin hydrolysate-based media is 1.5-2 times higher in comparison with that of the media based on the digest of meat and casein, as demonstrated by the results of Vibrio cholerae scaled cultivation. Furthermore, worked out is the technology of ethanol regeneration after the rivanol-ethanolic precipitation of gamma globulin, alcohol content by volume being (93±1) % after the regeneration. It is demonstrated that the regenerated alcohol can be used as a precipitator in the process of anti-rabies serum fractioning. All in all, the developed techniques make it possible to utilize the wastes of anti-rabies immunoglobulin production and provide for further use of derivatives while producing medical immunobiological preparations
Liquid flow inside a cylindrical capillary with walls covered with a porous layer (Gel)
Viscous incompressible liquid flow in a long cylindrical capillary, the internal surface of which is covered with a permeable porous layer, is studied within the frameworks of three mathematical models. In the first model, the liquid flow in the porous layer is described by the Brinkman equation; according to the second one, the presence of the porous layer is taken into account using the Navier slip boundary conditions; and, in the third model, the Navier condition is imposed on the porous layer–liquid interface, with the flow inside
the porous layer being excluded. The theoretical predictions are compared with the experimental data that one of us has obtained for liquid flow rates in porous capillaries. The validity and appropriateness of the application of the proposed models are discussed
Atomic Structure of Multilayered Low-Contrast Fe/Cr Thin Films: Mathematical Formalism and Numerical Experiments
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