Laser-assisted synthesis in CueAleNi system and some of its properties

Published ArticleConditions of intermetallic phase synthesis during layerwise selective laser sintering/melting in CueAl eNi powdered system were explored. There to we used optical and scanning electron microscopy, EDX and XRD analysis for microstructure testing and intermetallide identification in porous 3D samples depending on the laser syntheses regimes. A high laser sintering ability of the prepared mixtures and shape memory effect in 3D samples by results of specific electrical resistance measurements were shown. Porosity of the laser-synthesized Al7Cu4Ni intermetallide led to a peak shifting by the temperature axis and the intervals of the AseAf austenite transformation and MseMf martensite transformation were 50 ÷ 80 C and þ25 ÷ 40 C respectively

Justification of stripping and development of a modular mine site for a combined coal mining method in Kuzbass on the example Baikaimskaya mine site

The article considers one actual method for development coal deposits in the Kuzbass by open-underground mining. The scientific and practical advantages of the proposed method due to the use of common infrastructure of coal mine and a modular mine site (subsequently transformed into a mining and technological structure operating according to the mine – longwall scheme) are presented. Currently, a development strategy for Kuzbass until 2035 has been developed. As part of the strategy, a draft program for subsoil use is being formed in the coal industry department. The program should take into account all the positive and negative aspects associated with coal mining in cities and municipal areas and also their prospects. In the Kuznetsk coal basin, 42 mines and 52 opencast mines are mining, of which 12 enterprises use partially unified infrastructure. According to the results of open-underground mining work conducted by the laboratory of the Institute of Coal and Coal Chemistry of the Siberian Branch of the Russian Academy of Sciences (Institute of Coal SB RAS), the list of sites includes favorable mining and geological conditions with incidence angles of up to 18 degrees. As open-pit coal production increases, many sites encounter such a parameter as maximum allowable (boundary) strip ratio. At the stage of preparing the feasibility study for the development of a coal deposit, this coefficient is calculated first of all, since duration of enterprise’s work and its economic component depend on it. In order to increase parameters, it is necessary to carry out transition from open works to underground. As a result, coal mine will not work at a loss, providing production with an economically disadvantageous strip ratio

Исследование равновесной структуры молекулы 3,4-дицианофуроксана

Objectives. The study set out to determine the equilibrium parameters of the 3,4-dicyanofuroxan molecule by means of molecule geometry optimization by quantum chemistry methods, verify the adequacy of the methods used, and compare the obtained results with X-ray diffraction analysis (XRD) and gas electron diffraction (GED) data.Methods. Quantum chemical calculations were carried out using B3LYP, MP2, and CCSD(T) methods with 6-31G(d,p), cc-pVTZ, and aug-cc-pVTZ basis sets.Results. The equilibrium molecular structure of 3,4-dicyanofuroxan was refined by means of quantum chemical calculations using the Gaussian09 program. The geometrical parameters were compared with the structure of this compound in the solid phase and a number of related compounds in gas and solid phases. It was theoretically established that the planar equilibrium structure of the dicyanofuroxan molecule has CS symmetry. The structure of the free dicyanofuroxan molecule was found to differ depending on the phase. The B3LYP and CCSD(T) methods describe the molecular structure of dicyanofuroxan more accurately than the MP2 method. A regularity was revealed, according to which an increase in the basis, as a rule, leads to a better agreement of the geometry, regardless of the functional.Conclusions. The calculations performed are in good agreement with the literature data and results of joint analysis by GED and XRD. The effect of cyano substituents on the ring geometry is observed in comparison with the literature data for the dicyanofuroxan molecule. For the molecule in question, it is better to use the B3LYP/aug-cc-pVTZ method. The values of geometric parameters obtained by this method are in better agreement with the structure in the gas phase. The discrepancies with the experimental XRD results may be due to interactions in the crystal structure. Differences in the geometric parameters obtained on the basis of different functionals and bases make this molecule interesting for experimental structural studies using GED or microwave spectroscopy, which will permit the identification of optimal methods and bases for obtaining the geometric parameters of furoxan class molecules.Цели. Определение равновесных параметров молекулы 3,4-дицианофуроксана посредством оптимизации геометрии молекулы методами квантовой химии, проверка адекватности используемых методов, а также сопоставление полученных результатов с данными рентгенодифракционного анализа (РСА) и газовой электронографии (ГЭ) родственных соединений.Методы. Квантовохимические расчеты методами B3LYP, MP2 и CCSD(T) c базисными наборами 6-31G(d,p), cc-pVTZ и aug-cc-pVTZ.Результаты. Уточнена равновесная молекулярная структура 3,4-дициано- фуроксана с помощью квантово-химических расчетов в программе Gaussian09. Проведено сравнение геометрических параметров со структурой данного соединения в твердой фазе и с рядом родственных соединений в газовой и твердой фазе. Теоретически установлено, что равновесная структура молекулы дицианофуроксана является плоской и имеет симметрию CS. Установлено, что структура свободной молекулы дицианофуроксана в зависимости от фазы различается. Методы CCSD(T) и B3LYP точнее описывает молекулярную структуру дицианофуроксана по сравнению с методом MP2. Выявлена закономерность, согласно которой увеличение базиса, как правило, приводит к лучшему согласованию геометрии независимо от функционала.Выводы. Проведенные расчеты хорошо согласуются с литературными данными, а также результатами совместного анализа методами ГЭ и РСА. Влияние циано-заместителей на геометрию кольца наблюдается в сравнении с литературными данными для молекулы дицианофуроксана. Для рассматриваемой молекулы лучше использовать метод B3LYP/aug-cc-pVTZ. Значения геометрических параметров, полученные этим методом, лучше согласуются со структурой в газовой фазе. Расхождения с экспериментальными результатами РСА могут быть обусловлены взаимодействиями в кристаллической структуре. Различия в геометрических параметрах, полученных на основе разных функционалов и базисов, делают эту молекулу интересной для проведения экспериментального структурного исследования методами ГЭ или микроволновой спектроскопии, что позволит в будущем найти оптимальные методы и базисы для получения геометрических параметров молекул класса фуроксанов

PHENOTYPIC CHARACTERIZATION AND INTRACELLULAR CYTOKINES OF MEMORY T-CELLS IN MULTIPLE SCLEROSIS PATIENTS AFTER T-CELL VACCINATION

Multiple sclerosis (RS) patients were treated with a vaccine consisted of autological mielin-reactive T-cells. Effector memory CD8+ CD45RO+CD62L- T-cells as well as central memory CD4+ CD45RO+CD62L+ and CD8+ CD45RO+CD62L+ T-cells were significantly increased in MS patients as compared with levels in healthy individuals. T-cells vaccination had no effect on the T-cells memory subpopulation composition. However, vaccine-treated RS patients had significant (by 2 fold) reduction of relative quantity of CD4+IFNγ+IL-4— and CD8+IFNγ+IL-4— memory T-cells, as well as suppression by 6 fold of CD4+ memory cells number, which produce both kinds of cytokines

Continuous selections of multivalued mappings

This survey covers in our opinion the most important results in the theory of continuous selections of multivalued mappings (approximately) from 2002 through 2012. It extends and continues our previous such survey which appeared in Recent Progress in General Topology, II, which was published in 2002. In comparison, our present survey considers more restricted and specific areas of mathematics. Note that we do not consider the theory of selectors (i.e. continuous choices of elements from subsets of topological spaces) since this topics is covered by another survey in this volume

Primary prevention of the main dental diseases in children at different stages of orthodontic treatment with bracket systems

Aim. Evaluation of the effective preventive methods of dental caries in children with dentoalveolar anomalies. Methods. Orthodontic treatment was received by 50 children aged 12-14 years with dentoalveolar anomalies who were treated by an orthodontist using ligature bracket and who had a compensated form of dental caries before the beginning of the hardware treatment. In the first group of children (control, 25 subjects) professional oral hygiene twice a year was followed by the coating of all teeth with fluoride. Children of the second group (25 subjects) after professional oral hygiene twice a year had their teeth covered with tooth enamel around brackets with Clinpro XT Varnish (3M ESPE) material containing fluorine, calcium and phosphate compounds. Dental examination every three months included assessment of oral hygiene and the state of the gums, the presence of carious defects, fillings and removed teeth, followed by the calculation of the main dental indices. Results. On the basis of studies of the dental status in children undergoing orthodontic treatment using brackets, the main dental indices such as DCF (decay/missing/filled), complex periodontal index, papillary-marginal-alveolar index were characterized at the stages of treatment. The analysis of the recorded values was performed in the comparison groups for each research method and the main statistically significant differences were identified. The study revealed that children from group 2 had positive dynamics of the state of periodontium within 18 months: the value of papillary-marginal-alveolar index among children from group 2 decreased by 5.4 times, the value of complex periodontal index decreased by 3.5 times. Children from group 2 had a significantly lower incidence of caries compared to the control group after 18 months of remineralizing therapy: the increase of complex periodontal index among children receiving orthodontic treatment with Clinpro XT Varnish coverage twice a year was only 1.42±0.16, incidence of caries of teeth surface reduced by 55%. Conclusion. On the basis of these studies, a comparative characteristics of the dental indices was performed at the stages of treatment using the brackets, depending on the used primary preventive measures; dental status of children at the stages of orthodontic treatment have their features: special oral hygiene tools should be guided by hygiene indices and complemented by remineralizing drugs