A theoretical study of the structural phases of Group 5B - 6B metals and their transport properties

In order to predict the stable and metastable phases of the bcc metals in the block of the Periodic Table defined by groups 5B to 6B and periods 4 to 6, as well as the structure dependence of their transport properties, we have performed full potential computations of the total energies per unit cell as a function of the c/a ratio at constant experimental volume. In all cases, a metastable body centered tetragonal (bct) phase was predicted from the calculations. The total energy differences between the calculated stable and metastable phases ranged from 0.09 eV/cell (vanadium) to 0.39 eV/cell (tungsten). The trends in resistivity as a function of structure and atomic number are discussed in terms of a model of electron transport in metals. Theoretical calculations of the electrical resistivity and other transport properties show that bct phases derived from group 5B elements are more conductive than the corresponding bcc phases, while bct phases formed from group 6B elements are less conductive than the corresponding bcc phases. Special attention is paid to the phases of tantalum where we show that the frequently observed beta phase is not a simple tetragonal distortion of bcc tantalum

Multimedia technologies in vocational education

Modern higher professional education is aimed at the formation of a highly qualified competent specialist. In the conditions of the competence approach, there is an active introduction in the educational process of multimedia technologies. This is one of the most rapidly developing areas of information technology. Therefore, the training of students should be carried out with the use of various information and communication tools, ensuring the improvement of the quality of education. The purpose of the article is to present the experience of training students of pedagogical University using multimedia technologies. The analysis of the impact of these technologies on the motivation and training of students when studying discipline "technology of training teachers of the past" (media technologies have been embedded in the discipline content). For the study, we measured the motivation of students. We compared the indicators of motivation diagnostics in 2017 (before the introduction of multimedia technologies) and 2018 (after the introduction of technologies). We compared the motives of creative realization (MTR) and professional motives (PM). According to the control event on the discipline "Technologies of teaching teachers of the past", we found that the percentage of "excellent" in 2018 has increased significantly, the percentage of unsatisfactory ratings have decreased. The obtained data allowed detecting positive changes after the introduction of multimedia technologies into the educational process. The motivation of students to study the discipline has increased, their preparedness has increased, and the quality of education has increased. The high efficiency of multimedia technologies was determined, so their implementation in the training of students of pedagogical University will continue

The soft and the hard pomerons in hadron elastic scattering at small t

We consider simple-pole descriptions of soft elastic scattering for pp, pbar p, pi+ p, pi- p, K+ p and K- p. We work at t and s small enough for rescatterings to be neglected, and allow for the presence of a hard pomeron. After building and discussing an exhaustive dataset, we show that simple poles provide an excellent description of the data in the region - 0.5 GeV^2 < t < -0.1 GeV^2, 6 GeV<sqrt(s)< 63 GeV. We show that new form factors have to be used, and get information on the trajectories of the soft and hard pomerons.Comment: 27 pages, 9 figures, LaTeX. A few typos fixed, and references correcte

ПОДБОР ПАРАМЕТРОВ ПОЛИКАПИЛЛЯРНОЙ КОЛОНКИ ДЛЯ ПОРТАТИВНЫХ ГАЗОАНАЛИЗАТОРОВ ПО ИНДЕКСАМ КОВАЧА

Short straight multicapillary columns (MCC) allow for fast gas chromatographic separation. However, their limited efficiency makes it difficult to use them for the analysis of multicomponent mixtures. Therefore, it is important to preliminarily evaluate the possibility of separation of target substances, based on the available information about their characteristics, in particular, by retention indices (RI). The paper provides an example of the choice of MCC and chromatographic conditions for the separation of explosives in stationary phases OV-5 and SE-54. To find the correspondence of the retention indices of the target substances with their retention factors k on the studied MCCs, the retention times of C10−C19 n-alkanes were experimentally determined at different column temperatures. Then the dependences of the calculated lnk on the quantity of carbon atoms m in n-alkanes CmH2m+2  were plotted and approximated by linear functions ln k = a + bm and their coefficients a and b were found for each temperature. From where, it was easy to calculate the retention factors of the target substances by their RI, assuming that RI = m·100, as well as to estimate the MCC efficiency required to separate neighboring peaks to obtain the desired level of separation. Based on the obtained equations, the explosives retention factors for MCCs at different temperatures were calculated and their required efficiency for separating adjacent peaks was estimated. The retention factors experimentally determined for some explosives on the MCCs at 140 °C turned out to be quite close to the theoretically calculated ones. In the future, the similar approach can be used to predict the possibility of gas chromatographic separation of mixtures of dangerous substances such as narcotic drugs.Key words: fast gas chromatography, multicapillary column, chromatographic column selection, retention indices, explosivesDOI: http://dx.doi.org/10.15826/analitika.2022.26.1.003A.P. Efimenko1, I.I. Naumenko2, E.V.Kirillova3, A.A. Shorokhov31Multichrom ltd., Arbusova str. 4a,  b. 1, Novosibirsk, 630117,Russian Federation2Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyga 3, Novosibirsk, 630090,Russian Federation 3«SPO «Analitpribor», Babushkina str. 3, Smolensk, 214031, Russian FederationКороткие прямые поликапиллярные колонки (ПКК) позволяют проводить быстрые газохроматографические разделения, однако их ограниченная эффективность требует тщательного подбора ПКК при анализе многокомпонентных смесей. Поэтому при решении конкретной аналитической задачи актуально предварительно оценить возможность разделения целевых веществ, опираться на доступные сведения об их характеристиках, в частности, на индексы удерживания (RI). В настоящей работе приведен пример подбора ПКК и условий хроматографирования для разделения смесей взрывчатых веществ (ВВ) на неподвижных фазах (НФ) OV-5 и SE-54, выбранных нами из-за того, что известные индексы удерживания ВВ в основном определены на НФ подобного состава. Для нахождения соответствия индексов удерживания целевых веществ с их фактором удерживания k на исследуемых ПКК экспериментально были определены времена удерживания н-алканов С10 – С19 при различных температурах колонок, после чего построены зависимости рассчитанных ln k от числа атомов углерода m в н-алканах CmH2m+2 и аппроксимацией линейной функцией ln k = a + bm для каждой температуры найдены коэффициенты аппроксимации a и b. Откуда легко можно было вычислить факторы удерживания целевых веществ по их RI, считая, что RI = m·100, а также оценить эффективность ПКК, достаточную для разделения соседних пиков целевых веществ с необходимой степенью разделения. На основании полученных уравнений рассчитаны факторы удерживания ВВ для ПКК при разных температурах и оценена необходимая эффективность для разделения соседних пиков. Экспериментально определенные для некоторых ВВ факторы удерживания на ПКК с исследуемыми НФ при 140 оС оказались достаточно близки к теоретически рассчитанным. В дальнейшем подобный подход может быть использован для прогноза возможности газохроматографического разделения смесей опасных веществ или соединений, обращение с которыми имеет законодательные ограничения.Ключевые слова: экспрессная газовая хроматография, поликапиллярные колонки, подбор хроматографических колонок, индексы удерживания, взрывчатые веществаDOI: http://dx.doi.org/10.15826/analitika.2022.26.1.00

The Hidden Promotion of Unconventional Sexual Relations Among Minors in Social Networks as a Destructive Social Phenomenon

В ходе исследования были выделены специфические маркеры формирования толерантного отношения детей и подростков к сексуальной инаковости. Контент-анализ постов из популярных сообществ сети Интернет позволил выявить среднее соотношение, риторику и характерные черты скрытых «пропагандистских» материалов.In the course of the study, specific markers of the formation of a tolerant attitude of children and adolescents to sexual otherness were identified. Content analysis of posts from popular Internet communities revealed the average ratio, rhetoric and characteristic features of hidden “propaganda” materials

Surface Properties of the Half- and Full-Heusler Alloys

Using a full-potential \textit{ab-initio} technique I study the electronic and magnetic properties of the (001) surfaces of the half-Heusler alloys, NiMnSb, CoMnSb and PtMnSb and of the full-Heusler alloys Co$_2$MnGe, Co$_2$MnSi and Co$_2$CrAl. The MnSb terminated surfaces of the half-Heusler compounds present properties similar to the bulk compounds and, although the half-metallicity is lost, an important spin-polarisation at the Fermi level. In contrast to this the Ni terminated surface shows an almost zero net spin-polarisation. While the bulk Co$_2$MnGe and Co$_2$MnSi are almost half-ferromagnetic, their surfaces lose the half-metallic character and the net spin-polarisation at the Fermi level is close to zero. Contrary to these compounds the CrAl terminated (001) surface of Co$_2$CrAl shows a spin polarisation of about 84%.Comment: 14 pages, 6 figure

Forecasting of the Socio-Economic Damage Resulting from Outbreaks of Infectious Diseases, by the Example of Crimean Hemorrhagic Fever

Objective of the study was to develop a method of assessment and forecasting of socio-economic damage inflicted by the outbreaks of infectious diseases using DALY index by the example of Crimean hemorrhagic fever. WHO expert-designed DALY index was adapted for use in the territory of the Russian Federation with due account of GDP values and age distribution among the population. Put forward was a scheme for prognostication of a possible social damage caused by infectious disease outbreak, expressed in the aggregate number of wasted years of productive life and economic loss resulted from GDP decrement. The method developed can be used for forecasting of socio-economic damage inflicted by the outbreaks of infectious diseases and evaluation of effectiveness as regards anti-epidemic and therapeutic interventions. Carried out has been assessment of economic and social losses which resulted from outbreaks of Crimean hemorrhagic fever in the Southern Federal District of Russia inclusive of the data on morbidity rates over the period of 1999-2010. Major economic damage is factored by the labor forces loss consequent to fatal cases of infection. Such a method of prognostication based on DALY index has been implemented in the territory of the Russian Federation for the first time ever

Limitations of the two-media approach in calculating magneto-optical properties of layered systems

It is shown that in polar geometry and normal incidence the 2x2 matrix technique - as discussed in detail in a preceeding paper [Phys. Rev. B 65, 144448 (2002)] - accounts correctly for multiple reflections and optical interferences, and reduces only in the case of a periodic sequence of identical layers to the Fresnel formula of reflectivity, which in turn is the theoretical basis of the two-media approach, widely used in the literature to compute magneto-optical Kerr spectra. As a numerical example ab-initio calculations of the optical constants for an fcc Pt semi-infinite bulk using the spin-polarized relativistic screened Korringa-Kohn-Rostoker method show very good agreement with experimental data.Comment: 16 pages (LaTeX), 4 figures (Encapsulated PostScript), appears in Phys. Rev. B 66, 1744XX (2002

RNA CoSSMos: Characterization of Secondary Structure Motifs—a searchable database of secondary structure motifs in RNA three-dimensional structures

RNA secondary structure is important for designing therapeutics, understanding protein–RNA binding and predicting tertiary structure of RNA. Several databases and downloadable programs exist that specialize in the three-dimensional (3D) structure of RNA, but none focus specifically on secondary structural motifs such as internal, bulge and hairpin loops. The RNA Characterization of Secondary Structure Motifs (RNA CoSSMos) database is a freely accessible and searchable online database and website of 3D characteristics of secondary structure motifs. To create the RNA CoSSMos database, 2156 Protein Data Bank (PDB) files were searched for internal, bulge and hairpin loops, and each loop's structural information, including sugar pucker, glycosidic linkage, hydrogen bonding patterns and stacking interactions, was included in the database. False positives were defined, identified and reclassified or omitted from the database to ensure the most accurate results possible. Users can search via general PDB information, experimental parameters, sequence and specific motif and by specific structural parameters in the subquery page after the initial search. Returned results for each search can be viewed individually or a complete set can be downloaded into a spreadsheet to allow for easy comparison. The RNA CoSSMos database is automatically updated weekly and is available at http://cossmos.slu.edu

Selection of the parameters of a multicapillary column for portable gas analyzers by Kovach indices

Короткие прямые поликапиллярные колонки (ПКК) позволяют проводить быстрые газохроматографические разделения, однако их ограниченная эффективность требует тщательного подбора ПКК при анализе многокомпонентных смесей. Поэтому при решении конкретной аналитической задачи актуально предварительно оценить возможность разделения целевых веществ, опираться на доступные сведения об их характеристиках, в частности, на индексы удерживания ( RI ). В настоящей работе приведен пример подбора ПКК и условий хроматографирования для разделения смесей взрывчатых веществ (ВВ) на неподвижных фазах (НФ) OV-5 и SE-54, выбранных нами из-за того, что известные индексы удерживания ВВ в основном определены на НФ подобного состава. Для нахождения соответствия индексов удерживания целевых веществ с их фактором удерживания k на исследуемых ПКК экспериментально были определены времена удерживания н-алканов С10 - С19 при различных температурах колонок, после чего построены зависимости рассчитанных ln k от числа атомов углерода m в н-алканах CmH2m+2 и аппроксимацией линейной функцией ln k = a + bm для каждой температуры найдены коэффициенты аппроксимации a и b . Откуда легко можно было вычислить факторы удерживания целевых веществ по их RI , считая, что RI = m· 100, а также оценить эффективность ПКК, достаточную для разделения соседних пиков целевых веществ с необходимой степенью разделения. На основании полученных уравнений рассчитаны факторы удерживания ВВ для ПКК при разных температурах и оценена необходимая эффективность для разделения соседних пиков. Экспериментально определенные для некоторых ВВ факторы удерживания на ПКК с исследуемыми НФ при 140 оС оказались достаточно близки к теоретически рассчитанным. В дальнейшем подобный подход может быть использован для прогноза возможности газохроматографического разделения смесей опасных веществ или соединений, обращение с которыми имеет законодательные ограничения.Short straight multicapillary columns (MCC) allow for fast gas chromatographic separation. However, their limited efficiency makes it difficult to use them for the analysis of multicomponent mixtures. Therefore, it is important to preliminarily evaluate the possibility of separation of target substances, based on the available information about their characteristics, in particular, by retention indices ( RI ). The paper provides an example of the choice of MCC and chromatographic conditions for the separation of explosives in stationary phases OV-5 and SE-54. To find the correspondence of the retention indices of the target substances with their retention factors k on the studied MCCs, the retention times of C10-C19 n-alkanes were experimentally determined at different column temperatures. Then the dependences of the calculated ln k on the quantity of carbon atoms m in n-alkanes CmH2m+2 were plotted and approximated by linear functions ln k = a + bm and their coefficients a and b were found for each temperature. From where, it was easy to calculate the retention factors of the target substances by their RI , assuming that RI = m· 100, as well as to estimate the MCC efficiency required to separate neighboring peaks to obtain the desired level of separation. Based on the obtained equations, the explosives retention factors for MCCs at different temperatures were calculated and their required efficiency for separating adjacent peaks was estimated. The retention factors experimentally determined for some explosives on the MCCs at 140 °C turned out to be quite close to the theoretically calculated ones. In the future, the similar approach can be used to predict the possibility of gas chromatographic separation of mixtures of dangerous substances such as narcotic drugs