Generalizing Binary Solubility Data for Low-Volatile Liquids in Supercritical Fluids

EXISTING GENERALIZATION METHODS The key parameters that govern the feasibility of the separation of a mixture by supercritical fluid extraction are the binary solubilities of the components of the mixture in the extractant over a wide range of state variables. Several approaches to predicting the binary solubilities of liquids in compressed gases are known (1) where y i and y j are the concentrations (mole fractions) of the components; B ii is the second virial coefficient, which accounts for the interaction between identical molecules; B ij is the second virial cross coefficient, which accounts for the interaction between different molecules; and v m and z m are the molar volume and the compressibility of the gas phase, respectively. Within the framework of the thermodynamic similarity method, B ij is computed by various relations of the form where P cr and v cr are, respectively, the critical pressure and the critical molar volume of the component; is the characteristic temperature; and ω ij is the characteristic acentricity factor. There is a comprehensive review [2] of methods for calculating the characteristic cross parameters of mixtures, including higher order virial coefficients. ω ij is usually defined as the arithmetic mean of the acentricity factors of the mixture components. It was suggested [1] to calculate the characteristic temperature with the use of the empirical binary intermolecular interaction parameter k ij : ). = A generalized formula for k ij has been derived [1] for the interaction of organic liquids with a compressed gaseous solvent. The formula gives k ij as a function of the number of carbon atoms in the molecule of the dissolved liquid: where n is the number of carbon atoms in the molecules of dissolved n -paraffins, ketones, alcohols, and aromatic hydrocarbons. The interactions of nonpolar molecules with one another and of nonpolar molecules with polar molecules have been considered. The generalized formula is empirical, and the discrepancy between the parameters k ij obtained by experimental data processing and the generalized curve considerably exceeds the experimental error. The binary solubilities of low-volatile substances, including solids, have been represented [3] as a function of the solvent density: where y is the binary solubility (mole fraction), P is the pressure in the system, P 0 is the standard pressure, ρ is the solvent density, and ρ 0 is the standard solvent density. The parameters A and B are interrelated b

Направления совершенствования деятельности региональных банков на территории Республики Татарстан

The purpose of this study is to develop tools for assessing the state of regional banks and to justify decisions on the allocation of resources between their business areas by adapting existing methods of banking management to the new economic environment.The authors apply both general scientific methods (induction, deduction, analysis, synthesis) and special methods: systematic and retrospective analysis of existing developments in bank decisions.The results of the application of these methods are the mathematical models describing the functioning of the credit-deposit and transaction of commercial banks of Tatarstan in the past three years from the point of elasticity of actives and liabilities’ substitution. In the paper, we systematized the indicators of actives and liabilities of the five largest commercial banks in Tatarstan in 2019–2022, we approved the equations that characterize these actives and liabilities’ substitution elasticity in MS Excel.The conclusion is that in most cases, there is a unitary elasticity of their mutual substitution, which leads to the conclusion that the Tatarstan banking system is currently in the growth stage of a new life cycle, which began in 2014, after the Russian economy entered new realities due to sanctions pressure. The recommendations were formulated for the banks of Tatarstan in terms of improving the quality of loan portfolios in new conditions: they should improve the methods of making decisions about the loans for companies’ business activities which are first created.Цель исследования —  разработка инструментария оценки состояния региональных банков и обоснования решений о распределении ресурсов между направлениями их бизнеса посредством адаптации существующих методов банковского менеджмента к особенностям новой экономической среды. Авторы применяют как общенаучные методы (индукция, дедукция, анализ, синтез), так и специальные: системный и ретроспективный анализ существующих наработок в сфере обоснования решений банковского риск-менеджмента. Результатом применения указанных методов являются математические модели, описывающие функционирования кредитно-депозитного и транзакционного бизнесов коммерческих банков Татарстана в прошедшие 3 года с позиции эластичности взаимного замещения разных видов активов и пассивов. В ходе работы обобщены показатели состояния активов и пассивов пяти крупнейших коммерческих банков Татарстана за 2019–2022 гг., в MS Excel подобраны уравнения, характеризующие эластичность замещения разных видов активов и пассивов.Сделан вывод, что в большинстве случаев имеет место единичная эластичность их взаимного замещения, что подводит к заключению, что банковская система Татарстана в настоящее время находится на этапе роста в новом жизненном цикле, начавшемся в 2014 г., после вхождения российской экономики в новые реалии, обусловленные санкционным давлением. Сформулированы рекомендации для региональных банков Республики Татарстан в части повышения качества кредитных портфелей в новых условиях, а именно: совершенствование методов принятия решений о кредитовании корпоративных клиентов по новым создаваемым направлениям их бизнеса

Кредитные риски российских коммерческих банков: новые подходы к управлению

In the realities of the modern domestic economy, the process of risk management of commercial banks associated to credit corporate customers, acquires new content. The assessment of what place in the company’s activity has a work that contributes to solving the most pressing problems of our time: environment, social and general corporate governance comes to the fore. As a result, the focus is on a group of lending risks known as ESG. Since the areas of work of clients — legal entities, with which these risks are associated, and described mainly by qualitative, non-formalized characteristics, a difficult task for modern bank risk-management becomes normalizing the process of their evaluation when making specific decisions on the loan. This explains the interest and relevance of this research, the object of which is the risk management subsystem for lending to corporate clients by commercial banks, the subject is the consideration of ESG factors in this process. The purpose of the paper is to develop the basics of decision-making tools in the management of bank credit risks, with this group of factors. The authors apply methods of both general scientific (induction, deduction, analysis, synthesis) and special: system and retrospective analysis of existing developments in the field of justification of decisions of bank risk management. The theoretical significance of the research results consists in a complex analysis of the role and place of ESG-risks in the overall risk landscape and the integration of environmental, social and managerial factors into credit risk assessment. Basic principles of construction of phenomenological model, used to support credit decisions by banks of corporate clients taking into account ESG-factors that influence their activity, have been developed.В реалиях современной отечественной экономики процесс управления рисками коммерческих банков, связанными с кредитованием корпоративных клиентов, обретает новое содержание. На первый план выходит оценка того, какое место в жизни компании занимает работа, способствующая решению наиболее актуальных проблем современности: экологических (environment), социальных (social) и общего корпоративного управления (governance). В результате в центре внимания оказывается группа рисков кредитования, известная как ESG. Поскольку направления работы клиентов — юридических лиц, с которыми связаны эти риски, описываются в основном качественными, неформализованными характеристиками, сложной задачей для современного банковского риск-менеджмента становится упорядочивание процесса их оценки при принятии конкретных решений о выдаче кредита. Этим обусловлена актуальность данного исследования, объектом которого является подсистема управления рисками кредитования корпоративных клиентов коммерческими банками, предметом — учет ESG-факторов в данном процессе. Цель исследования — разработка основ инструментария принятия решений в управлении банковскими кредитными рисками с учетом данной группы факторов. Авторы применяют методы как общенаучные (индукция, дедукция, анализ, синтез), так и специальные: системный и ретроспективный анализ существующих наработок в сфере обоснования решений банковского риск-менеджмента. Теоретическая значимость результатов исследования заключается в комплексном анализе роли и места ESG-рисков в общем ландшафте рисков и интеграции экологических, социальных и управленческих факторов в оценку кредитного риска. Разработаны базовые принципы построения феноменологической модели, используемой для обоснования решений о кредитовании банками корпоративных клиентов с учетом ESG-факторов, влияющих на их деятельность

Colloquium: Trapped ions as quantum bits -- essential numerical tools

Trapped, laser-cooled atoms and ions are quantum systems which can be experimentally controlled with an as yet unmatched degree of precision. Due to the control of the motion and the internal degrees of freedom, these quantum systems can be adequately described by a well known Hamiltonian. In this colloquium, we present powerful numerical tools for the optimization of the external control of the motional and internal states of trapped neutral atoms, explicitly applied to the case of trapped laser-cooled ions in a segmented ion-trap. We then delve into solving inverse problems, when optimizing trapping potentials for ions. Our presentation is complemented by a quantum mechanical treatment of the wavepacket dynamics of a trapped ion. Efficient numerical solvers for both time-independent and time-dependent problems are provided. Shaping the motional wavefunctions and optimizing a quantum gate is realized by the application of quantum optimal control techniques. The numerical methods presented can also be used to gain an intuitive understanding of quantum experiments with trapped ions by performing virtual simulated experiments on a personal computer. Code and executables are supplied as supplementary online material (http://kilian-singer.de/ent).Comment: accepted for publication in Review of Modern Physics 201

Isolation, Purification and Evaluation of Serological Activity of Rabies Virus Antigens

Objective of the study is to evaluate the serological activity of rabies virus antigens isolated from the brain tissue of mice by homogenization on FastPrep followed by ultracentrifugation. Materials and methods. Producer strain of the rabies virus “Ovechiy” GNKI. The rabies virus was isolated from the brain tissue of experimentally infected mice, followed by the study of the electrophoretic profile. The serological activity of the virus components was assessed by immunoblot and ELISA using specific anti-rabies sera.Results and conclusions. In the course of comparing the methods of isolation and purification of the rabies virus antigen, it was found that most optimal one is to use a homogenization on FastPrep-24, followed by fractionation in a sucrose gradient. As a result of fractionation in a graded sucrose density gradient with a concentration of 15–50 % at 25000 g for 120 min, five fractions of the rabies virus components were obtained. The maximum purified protein fraction was from 15–20 % sucrose zone, which corresponded to a molecular weight of 67 kDa. The specific antigen activity of the fraction in ELISA reached up the titers of 1:1280 (Specificity coefficient 2.2). Using immunoblot of antigens, obtained from the sucrose gradient in the range of 40–45 % and 20–35 % after ultracentrifugation, one major fraction of polypeptides (54 kDa) was detected, which showed the highest antigenic activity. The results obtained will be useful in the design of test systems for rabies screening and monitoring the effectiveness of anti-epizootic measures

The astrometric Gaia-FUN-SSO observation campaign of 99 942 Apophis

Astrometric observations performed by the Gaia Follow-Up Network for Solar System Objects (Gaia-FUN-SSO) play a key role in ensuring that moving objects first detected by ESA's Gaia mission remain recoverable after their discovery. An observation campaign on the potentially hazardous asteroid (99 942) Apophis was conducted during the asteroid's latest period of visibility, from 12/21/2012 to 5/2/2013, to test the coordination and evaluate the overall performance of the Gaia-FUN-SSO . The 2732 high quality astrometric observations acquired during the Gaia-FUN-SSO campaign were reduced with the Platform for Reduction of Astronomical Images Automatically (PRAIA), using the USNO CCD Astrograph Catalogue 4 (UCAC4) as a reference. The astrometric reduction process and the precision of the newly obtained measurements are discussed. We compare the residuals of astrometric observations that we obtained using this reduction process to data sets that were individually reduced by observers and accepted by the Minor Planet Center. We obtained 2103 previously unpublished astrometric positions and provide these to the scientific community. Using these data we show that our reduction of this astrometric campaign with a reliable stellar catalog substantially improves the quality of the astrometric results. We present evidence that the new data will help to reduce the orbit uncertainty of Apophis during its close approach in 2029. We show that uncertainties due to geolocations of observing stations, as well as rounding of astrometric data can introduce an unnecessary degradation in the quality of the resulting astrometric positions. Finally, we discuss the impact of our campaign reduction on the recovery process of newly discovered asteroids.Comment: Accepted for publication in A&

A new fast multi-domain BEM to model seismic wave propagation and amplification in 3D geological structures

International audienceThe analysis of seismic wave propagation and amplification in complex geological structures raises the need for efficient and accurate numerical methods. The solution of the elastodynamic equations using traditional boundary element methods (BEMs) is greatly hindered by the fully-populated nature of the matrix equations arising from the discretization. In a previous study limited to homogeneous media, the present authors have established that the Fast Multipole (FM) method reduces the complexity of a 3-D elastodynamic BEM to $N \log N$ per GMRES iteration and demonstrated its effectiveness on 3-D canyon configurations. In this article, the frequency-domain FM-BEM methodology is extented to 3-D elastic wave propagation in piecewise-homogeneous domains in the form of a FM-accelerated multi-region BE-BE coupling approach. This new method considerably enhances the capability of the BEM for studying the propagation of seismic waves in 3-D alluvial basins of arbitrary geometry embedded in semi-infinite media. Several fully 3-D examples (oblique SV-waves) representative of such configurations validate and demonstrate the capabilities of the multi-domain fast multipole approach. They include comparisons with available (low-frequency) results for various types of incident wavefields, and time-domain results obtained by means of Fourier synthesis

The astrometric Gaia-FUN-SSO observation campaign of 99942 Apophis

© 2015 ESO. Aims. Astrometric observations performed by the Gaia Follow-Up Network for Solar System Objects (Gaia-FUN-SSO) play a key role in ensuring that moving objects first detected by ESA's Gaia mission remain recoverable after their discovery. An observation campaign on the potentially hazardous asteroid (99 942) Apophis was conducted during the asteroid's latest period of visibility, from 12/21/2012 to 5/2/2013, to test the coordination and evaluate the overall performance of the Gaia-FUN-SSO. Methods. The 2732 high quality astrometric observations acquired during the Gaia-FUN-SSO campaign were reduced with the Platform for Reduction of Astronomical Images Automatically (PRAIA), using the USNO CCD Astrograph Catalogue 4 (UCAC4) as a reference. The astrometric reduction process and the precision of the newly obtained measurements are discussed. We compare the residuals of astrometric observations that we obtained using this reduction process to data sets that were individually reduced by observers and accepted by the Minor Planet Center. Results. We obtained 2103 previously unpublished astrometric positions and provide these to the scientific community. Using these data we show that our reduction of this astrometric campaign with a reliable stellar catalog substantially improves the quality of the astrometric results. We present evidence that the new data will help to reduce the orbit uncertainty of Apophis during its close approach in 2029. We show that uncertainties due to geolocations of observing stations, as well as rounding of astrometric data can introduce an unnecessary degradation in the quality of the resulting astrometric positions. Finally, we discuss the impact of our campaign reduction on the recovery process of newly discovered asteroids

Creation of models for forecasting banks' net incomes from currency operations

In the present article the author has the aims, such as identifying the role of net incomes from currency operations in the process of forming commercial banks' profit, exploring present models for forecasting their size and creation new ones, which take in account different factors which influence on it. They're created on the base of system structural, correlation and factorial analysis. In the result of this investigation the new models were received, they express the specific of each kind of currency operations (conversion, loans and deposits and cash settlement), and the model for the common net income from all kinds of currency operations