Fine Chemical Technologies (E-Journal) / Тонкие химические технологии
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О ДОПОЛНИТЕЛЬНОЙ ВОЗМОЖНОСТИ ДЛЯ ЧИСЛЕННОГО РЕШЕНИЯ ДИФФЕРЕНЦИАЛЬНЫХ УРАВНЕНИЙ В ЧАСТНЫХ ПРОИЗВОДНЫХ
Get PDFA substitution of an non-homogeneous term and of a differential operator by the difference of Laplace operators in the direct co-ordinate system and in the turned one in the partial differential equations of first, second and third order is proposed. The numerical solution obtained by solving the substituting equation corresponds to the exact solution of the initial equations.В дифференциальных уравнениях первого, второго и третьего порядков с граничными условиями, соответствующими их точным решениям, произведена замена неоднородного члена и дифференциального оператора соответствующего порядка на разность операторов Лапласа в прямой и повёрнутой системах координат. Численное решение, полученное при решении уравнения-заменителя, соответствует точному решению исходных уравнений
ДИНАМИКА СИСТЕМ, ДОПУСКАЮЩИХ СТРУКТУРНЫЕ ФАЗОВЫЕ ПЕРЕХОДЫ
Get PDFThe dynamics of active atoms that determine structure phase transitions in a solid body is considered in the context of the previously presented atom interaction model based on a special type of three-minimum potential. Periodical and soliton-like solutions of nonlinear differential equation of motion were obtained. The value of the bond energy of active atoms with respect to the potential barrier height in a single-particle potential with a triple minimum determines the character of a phase transition. Crystals of the MeI MeIIBX4 kind, as well as crystals and metals, on the surface of which atoms of gases and metals are absorbed, are considered as objects, in which the obtained results can be used.В рамках предложенной нами ранее модели взаимодействия атомов, основанной на трехямном потенциале специального вида, рассмотрена динамика активных атомов, определяющих структурные фазовые переходы в твердом теле. Получены периодические и солитоноподобные решения нелинейного дифференциального уравнения движения. Величина энергии связи активных атомов по отношению к высоте потенциального барьера в одночастичном потенциале с тройным минимумом определяет характер фазового перехода. В качестве объектов применения полученных результатов могут рассматриваться, в частности, кристаллы семейства MeIMeIIBX4, а также кристаллы и металлы, на поверхности которых абсорбируются атомы газов или металлов
ОБРАЗОВАНИЕ КОМПЛЕКСОВ МЕДИ(II) С ВОДОРАСТВОРИМЫМ β-ФУРФУРОЛОКСИМОМ
Get PDFThe paper is devoted to the interaction of copper(II) chloride with water soluble β-furfuraldoxime (N-(furan-2-ylmethyliden)hydroxylamine) in hydrochloric solutions. It was been revealed that the degree of copper(II) precipitation from aqueous solutions and hydrochloric solutions with the pH of 4 M HCl by this reagent is not higher than 52% even when the precipitant is used in abundance. These dependencies has been compared to the similar results of palladium(II) precipitation obtained when all other conditions were equal. It has been discovered that various complexes are formed when Cu(II) reacts with a β-furfuraldoxime and that it depends on the acidity of the solution. In weak acid solutions (0.01-0.1 M HCl) the «green» complex of composition [CuL4Cl2] was obtained and in this complex the oxime is coordinated with the central atom by an oxygen atom of the oxime group. The so-called «red» complex of composition [CuL2Cl2] is formed in the pH range of 1-4 M HCl and in ethanol. In this complex the coordination of ligand molecules is realized by the oxygen atom of the furan ring and by the oxygen of the oxime group. Reagent N-(furan-2-ylmethyliden)hydroxylamine can be used for practical quantitative release of palladium from hydrochloric solutions. However, it does not provide the separation of copper and palladium in their joint presence
ПРОГНОСТИЧЕСКАЯ МОДЕЛЬ ПРОТИВООПУХОЛЕВОГО ЭФФЕКТА ТАРГЕТНЫХ ПРЕПАРАТОВ ИММУНОТЕРАПИИ
Get PDFA prognostic model for constructing hypotheses about the relationship of combinations of cytokines with the proliferative activity of cancer cells is proposed. The model is based on the use of inductive inference methods. The methodology takes into account the synergistic interaction of cytokines and uses sequential construction of logical formulas for selecting groups of cytokines, a statistical analysis of contingency tables and logical integration of the obtained estimates. Implementation of the proposed method in the information system of forecasting the effect of targeted anticancer drugs in immunotherapy will greatly accelerate research in this area.На основе использования методов индуктивного вывода предложена прогностическая модель построения гипотез о взаимосвязи комбинации цитокинов с пролиферативной активностью раковых клеток. Модель учитывает синергическое взаимодействие цитокинов и использует последовательное построение логических формул для отбора групп цитокинов, статистический анализ таблиц сопряженности и логическую интеграцию полученных оценок. Реализация предложенной модели в рамках информационной системы прогнозирования противоопухолевого эффекта таргетных препаратов иммунотерапии позволит существенно ускорить научные исследования в этой области
ГОМОЯДЕРНОЕ ПОЛИЭДРИЧЕСКОЕ РАСШИРЕНИЕ В НОНАГИДРО-КЛОЗО-НОНАБОРАТНОМ АНИОНЕ [B9H9]2-
Get PDFNonahydro-closo-nonaborate anion possess the property of structural nonrigidity because of presence of three low-coordinated boron atoms. So it’s able to come into the reactions of polyhedral extension. This paper is devoted to the reactions of homoatomic polyhedral extension in nonahydrocloso-nonaborate anion [B9H9]2- in presence of triethylaminborane complex BH3·(C2H5)3N. It was shown that mixes of [B10H10]2- and [B12H12]2- salts in various molar ratios had been formed as products. These ratios depend on proportion of reagents. In presence of excess of triethylamin borane complex the molar ratio of products is 1:1. When equimolar amount of triethyamminborane complex used, the selectivity of process shifted to formation of [B10H10]2- anion. However the formation of [B12H12]2- still occurs in this conditions but the molar ratio of [B10H10]2-:[B12H12]2- is 5:1.Изучены реакции гомоядерного полиэдрического расширения нонагидро-клозо-нонаборатного аниона [B9H9]2- в присутствии триэтиламинборана BH3·(C2H5)3N. Показано, что в качестве основных продуктов образуются смеси солей анионов [B10H10]2- и [B12H12]2- с различными мольными соотношениями, которые варьируются в зависимости от соотношений исходных соединений
РЕКТИФИКАЦИЯ БИНАРНЫХ ДВУХФАЗНЫХ СМЕСЕЙ РАЗНОЙ ФИЗИКО-ХИМИЧЕСКОЙ ПРИРОДЫ: НОРМАЛЬНЫЙ РЕЖИМ И ОТКЛОНЕНИЯ ОТ НЕГО
Get PDFIn this article, the normal continuous mode of distillation is considered using an example of binary two-phase mixture distillation. In practice, there are often deviations from the normal mode. It has been proved that the deviation leads to an increase in energy consumption for the ongoing process. In the industry, columns separating binary mixtures are normally the finishing apparatuses in the flow-sheet separation of multicomponent mixtures, which are obtained in the reactor as a result of main reactions as well as by-reactions. The distillation of binary mixtures is relatively simpler than that of multicomponent mixtures. In this regard, the fundamental parts of monographs especially in the thirties-forties of the last century started with the study of binary mixtures, although multicomponent mixtures were the main focus. The aim of analyzing this complex and the highly energy-intensive process is to facilitate the choice of a mathematical model for the process and the determination on its basis variance. Variance is a set of independent variables that allow calculation of a process only after taking into account the number of independent equations related to these variables. A case of deviation from the normal distillation regime where an under-heated liquid enters the column feed has been revised. This leads to an increase in energy consumption during distillation. Key indicators of the normal regime relative to the level of feed and the temperature of the liquid are shown in the text.Рассмотрено отклонение от нормального режима ректификации в случае подачи в колонну недогретой жидкости. Последнее приводит к завышению энергозатрат на ректификацию. Приводятся основные показатели нормального режима относительно уровня подачи, температуры подаваемой жидкости
ЭКСПЕРИМЕНТАЛЬНОЕ ОПРЕДЕЛЕНИЕ СКОРОСТЕЙ ЗАРОЖДЕНИЯ И РОСТА ЦЕНТРОВ ФАЗОВЫХ ПРЕВРАЩЕНИЙ
Get PDFThe processes of granulation by crystallization of molten droplets in the flow of a cooling agent (prilling) and on the cooled surfaces of the granulators are widely used in the chemical and allied industries. The process of granulation (crystallization) of melts and qualitative indicators of granular products, their marketability is determined by the transfer phenomena in the phases and by the kinetics of crystallization and enantiotropic polymorphic transformations in the crystalline phase. Quantitatively the latter are given in the form of dependences of the rate of nucleation and growth of centers of transformation. The processes kinetics is usually less studied, but it determines the structure of the formed crystal phase and the maximum rate of the process. Therefore, most attention is focused on its study. The description of the scheme, of developed experimental laboratory facilities for the study of the rates of nucleation and growth of crystallization centers in the polycrystalline front of the growing group of crystals, as is the case when crystallization occurs in devices in real conditions (constrained growth of crystals) and single crystals in a thin layer (unrestricted growth of crystals) is given. The transfer of heat in the measuring cell and the sample and possible errors of experimental results were estimated using the natural scale method.EXPERIMENTAL DETERMINATION OF THE RATES OF NUCLEATION AND OF GROWTH OF PHASE TRANSFORMATION CENTER
ВЛИЯНИЕ МОЛЕКУЛЯРНО-МАССОВЫХ ХАРАКТЕРИСТИК ПОЛИЭТИЛЕНА НА ЭФФЕКТ СКОЛЬЖЕНИЯ
Get PDFThe rheological properties of polyethylene with different molecular weight characteristics were studied. Difference of molecular weight characteristics was found on the basis of melt flow index, and slip effect in the molten polyethylene flow was studied. The presence of slip effect is found in case of flowing polyethylene with a higher molecular weight in contrast to polyethylene with lower molecular weight at different temperatures. Changes of the slip effect parameters upon mixing polyethylenes with very much different molecular weight characteristics were studied.EFFECT OF POLYETHYLENE MOLECULAR MASS CHARACTERISTICS ON SLIP EFFEC
ВЗАИМОСВЯЗЬ ВНЕШНЕГО И ВНУТРЕННЕГО ЭНЕРГОСБЕРЕЖЕНИЯ ПРИ РЕКТИФИКАЦИИ БИНАРНЫХ СМЕСЕЙ
Get PDFThe comparison of energy consumption for rectification of binary mixtures in one-column and twocolumn apparatuses was carried out with the use of vapor flow energy from the first column for heating the second column. It is shown that the expected two-fold reduction of the flow of heat energy is impossible due to the decrease of the internal energy-saving.Проведено сравнение затрат теплоты при ректификации бинарных смесей в одной колонне и в двухколонной установке с использованием теплоты парового потока из первой колонны для обогрева второй. Показано, что ожидаемое в двухколонной установке снижение вдвое расхода тепловой энергии невозможно из-за уменьшения внутреннего энергосбережения в колоннах
Выделение некоторых высококипящих элементоорганических соединений методом препаративной газовой хроматографии
Get PDFPreparative gas chromatography is proposed to isolate some high-boiling organometallic compounds. Isolation of high-boiling substances should be conducted at a column temperature significantly below the boiling point, because most isolated compounds are thermally unstable at such temperatures. Stationary phases for preparative gas chromatography have a temperature limit of 350°C. The reduction of the column temperature is based on simultaneous changing the parameters of the chromatographic experiment (column length, impregnation degree, flow rate of the carrier gas). The influence of reducing the column temperature on the shape of the chromatographic peak is shown. The peak has an asymmetric shape, and its width increases. Therefore, the possibility of high-boiling substances preparative isolation depends on temperature decrease as the column separation efficiency is maintained.Метод препаративной газовой хроматографии предложен для выделения некоторых высококипящих элементоорганических соединений. Выделение высококипящих веществ необходимо проводить при температуре, значительно ниже температуры кипения, так как большинство выделяемых соединений термически неустойчивы при таких температурах. Неподвижные фазы для препаративной газовой хроматографии имеют температурный предел 350ºС. Рассмотрены особенности выделения высококипящих веществ при снижении температуры колонки относительно температуры кипения вещества. Понижение температуры колонки достигнуто путем одновременного изменения параметров хроматографического опыта (длины колонки, степени пропитки, скорости газа-носителя). Однако при увеличении отношения температуры кипения к температуре колонки наблюдается изменение формы пика, возрастание его ширины. Поэтому возможность препаративного выделения высококипящих веществ зависит от снижения температуры колонки при сохранении эффективности разделения