Relative stability of zincblende and wurtzite structure in CdX(X = S, Se, Te) series - A NMTO study

Using NMTO-downfolding technique we have revisited the issue of relative stability between zincblende (ZB) and wurtzite (WZ) symmetries in case of CdS, CdSe and CdTe semiconductors. Our computed ionicity factors using accurate NMTO-downfolding successfully brings out the right trend within the CdX series - CdS being most ionic stabilizes in WZ symmetry while CdSe and CdTe being more covalent stabilizes in ZB symmetry. Our NMTO constructed Wannier functions corresponding to only valence bands provide a nice demonstration of this fact. The tendency towards ZB stability is governed by the covalency which prefers isotropic nature of the tetrahedral bonds.Comment: 13 pages, 6 figures, 4 table

Investigation of Raman spectra and ionic conductivity of composites based on NaClO4 and KClO4 salts obtained by mechanoactivation

The work is aimed at studying the effect of mechanical activation on the structure and electrical conductivity of the NaClO4 – and KClO4 – basedcomposites. Based on the result of the analysis of the DSC curves of the (1–x) NaClO4 – x Al2O3 and (1–x) KClO4 – x Al2O3 composites measured while heating and cooling the samples, it was established that the enthalpy of phase transitions in them decreased with an increase in the concentration of the nanosized dopant. A complication of all active vibrational contours corresponding to internal vibrations of the molecular anion in the composites with increasing Al2O3 concentration and a shift of the band of the fully symmetric stretching vibration v1 (A) to a low-frequency region was revealed by Raman spectroscopy. Based on electrochemical impedance spectroscopy data, it was determined that for the 0.4NaClO4 – 0.6Al2O3 system subjected to mechanoactivation, the values of specific ionic conductivity increased by two orders of magnitude as compared to that of pure NaClO4, while for the 0.4KClO4 – 0.6Al2O3 system, the values of specific ionic conductivity increased by three orders of magnitude as compared to the initial salt at T = 320 °C.https://doi.org/10.15826/elmattech.2024.3.03

ОСОБЕННОСТИ ВОЗДЕЛЫВАНИЯ КАПУСТЫ ЦВЕТНОЙ И БРОККОЛИ В ПОЧВЕННО- КЛИМАТИЧЕСКИХ УСЛОВИЯХ РАВНИННОЙ, ПРЕДГОРНОЙ И ГОРНОЙ ПРОВИНЦИЙ ДАГЕСТАНА

Results of the study of possibility of cultivation of cauliflower and broccoli in the context of vertical zonality of Dagestan are presented. Physiological  characteristics, agriculture, and cultivation of early maturing varieties of cauliflower and broccoli during spring, summer, and autumn in condition of plain, piedmont, and mountain regions of Dagestan were studied. The high quality product of these crops was obtained in condition of Dagestan in the altitude of 1510 m above sea level.Представлены результаты изучения возможности выращивания капусты цветной и брокколи в разрезе вертикальной зональности Дагестана. Изучены физиологические особенности и агротехника возделывания скороспелых сортов капусты цветной и брокколи весенне-летне-осеннего периода созревания в почвенно-климатических условиях равнинной, предгорной и горной провинций. Установлено, что капуста цветная и брокколи дают полноценную продукцию высокого качества до высоты 1510 м над уровнем моря

ISOCHORIC HEAT CAPACITY OF 1% AQUEOUS SOLUTION OF MAGNESIUM CHLORIDE

Aim. The aim is to conduct an experimental study of isochoric heat capacity of 1% aqueous solution of magnesium chloride along the phase boundary curve.Method. In order to determine the isochoric heat capacity at the phase boundary curve we used the adiabatic calorimeter of KH. I. Amirkhanov.Results. Results of the study of the isochoric heat capacity depending on the temperature are given in tables and figures; the findings are compared with those of other researchers. When evaluating a complex system, we ought not to evaluate its effectiveness on the basis of only one criterion, even a very important, in this case must take into account the requirements of the technical, economic, environmental and of other natures.Conclusions. When solving optimization problems of efficiency in geothermal energy it is necessary to take into account the fact of the temperature dependence of the heat and density. The temperature dependence of the density and heat capacity in the calculations significantly affect the value of the efficiency criterion to be taken into account, otherwise the calculation error can be up to 20%. The data obtained from the isochoric heat capacity of aqueous solutions of magnesium chloride is compared with the data for water and aqueous solutions of NaCl and NaOH, obtained previously, which may be represented as a model of geothermal and sea water

Turbulence in the Russian Economy Management System

Topical events on economic and public arenas are eloquent of the beginning of a stage in manifestation of global market failures (fiasco) which cause increasing turbulence in the system of the economic development of advanced countries. The solution of this problem becomes particularly topical at that time when the globalization process, which is accompanied by world crises, rapidly grows and there is the need to make intelligent and educated decisions in a timely manner in the face of internal and external economy management change. Russia faces internal and geopolitical challenges and threats. External and internal factors, which cause the turbulent, namely, uncertain and chaotic development of the economy, have focused. As a fragment of the systemic way out of global turbulence can be considered the following: 1) on the basis of the fundamental classical economic theory it is necessary to reconstitute the reproduction chain, where production - distribution - exchange – consumption interact; 2) it is necessary to develop and implement a strategy of resource competitive advantages; 3) we offer to consider the import substitution as a new breakthrough to the growth in different industries where new chains of the rise in the cost of national welfare are developed. Keywords: Network economy, uncertainty, network effects, risk management, financial globalization, risks. JEL Classifications: E26, O1

Investigation of Raman Spectra and Ionic Conductivity of Composites Based on NaClO4 and KClO4 Salts Obtained by Mechanoactivation

Received: 27 November 2023. Accepted: 6 March 2024. Published online: 18 March 2024.The work is aimed at studying the effect of mechanical activation on the structure and electrical conductivity of the NaClO4 – and KClO4 – based composites. Based on the result of the analysis of the DSC curves of the (1–x) NaClO4 – x Al2O3 and (1–x) KClO4 – x Al2O3 composites measured while heating and cooling the samples, it was established that the enthalpy of phase transitions in them decreased with an increase in the concentration of the nanosized dopant. A complication of all active vibrational contours corresponding to internal vibrations of the molecular anion in the composites with increasing Al2O3 concentration and a shift of the band of the fully symmetric stretching vibration v1 (A) to a low-frequency region was revealed by Raman spectroscopy. Based on electrochemical impedance spectroscopy data, it was determined that for the 0.4NaClO4 – 0.6Al2O3 system subjected to mechanoactivation, the values of specific ionic conductivity increased by two orders of magnitude as compared to that of pure NaClO4, while for the 0.4KClO4 – 0.6Al2O3 system, the values of specific ionic conductivity increased by three orders of magnitude as compared to the initial salt at T = 320 °C.This study was carried out using the instruments of the Analytical Center of Collective Use of the Dagestan Federal Research Center of the Russian Academy of Sciences

Morphotropic Phase Boundary Enhanced Photocatalysis in Sm Doped BiFeO3

This paper presents the results of the synthesis of samarium-doped bismuth ferrite (BFO) nanoparticles by the solution combustion method. The dependence of BFO properties on the amount of the samarium (Sm) in the composition was studied. The synthesized nanocomposites were characterized by scanning electron microscopy SEM), X-ray diffractometry (XRD), Raman, Electron Diffuse Reflectance Spectroscopy (EDRS) and Electron Magnetic Resonance (EMR). The photocatalytic (PC) measurements showed the absence of a strict correlation between the PC activity and the crystallite size and band gap. An increase in the PC activity of BFO samples with 10 and 15% doping was observed and it was concluded that in controlling the PC properties in doped BFO, the processes of interfacial polarization at the boundaries of the morphotropic phase transition are of decisive importance. It was supposed that the internal electric field formed at these boundaries contributes to the efficient separation of photogenerated charge carriers

Компьютерная томография – метод обоснования минимально инвазивного подхода в лечении повреждений пищевода и их осложнений

The purpose of the study. To analyze possibilities of computed tomography (CT) for esophageal injuries and their complications as part of a differentiated approach to the choice of a minimally invasive treatment method.Materials and methods. The results of CT scans were analyzed in 25 patients with esophageal injuries of various etiologies who were treated at the N.V. Sklifosovsky Research Institute of SP in the period 2019–2020. CT was performed with oral and intravenous bolus contrast, primarily at admission and in dynamics, a total of 77 studies.Results. In all cases, direct and indirect CT signs of esophageal damage were detected, and the degree of involvement of surrounding organs and tissues in the pathological process was assessed. Based on the data obtained, the following variants of esophageal damage and its complications were identified: intramural esophageal hematoma (2); rupture of the thoracic esophagus without the development of purulent complications (2); rupture of the thoracic esophagus complicated by the development of mediastinitis (4); rupture of the thoracic esophagus with the development of mediastinitis and pleural empyema (13); rupture of the cervical calving of the esophagus, complicated by phlegmon of the neck and descending mediastinitis (4). Different patient management tactics were used for each variant. Thus, the selection and sequence of minimally invasive interventions, such as thoracoscopic sanitation mediastinal and pleural cavity, esophageal stenting, percutaneous endoscopic gastrostomy (CEG) and endoscopic vacuum aspiration system (E-VAS), were carried out taking into account CT data, including observations in dynamics.Conclusion. CT scan for esophageal injuries allows you to get complete information about both the nature of esophageal damage and its complications, to determine their type, localization and volume. CT data allow us to justify a minimally invasive approach in the treatment of esophageal injuries, to determine the order of interventions. CT studies performed in dynamics allow us to evaluate the effectiveness of treatment and to carry out timely correction of tactics.Цель исследования: проанализировать возможности компьютерной томографии (КТ) при повреждениях пищевода и их осложнениях в рамках дифференцированного подхода к выбору минимально инвазивного метода лечения.Материал и методы. Проведен анализ результатов КТ у 25 пациентов с повреждениями пищевода различной этиологии, находившихся на лечении в НИИ СП имени Н.В. Склифосовского в период 2019– 2020 гг. КТ проводилась с пероральным и внутривенным болюсным контрастированием, первично при поступлении и в динамике, всего 77 исследований.Результаты. Во всех случаях были выявлены прямые и косвенные КТ-признаки повреждения пищевода, а также оценена степень вовлечения в патологический процесс окружающих органов и тканей. На основании полученных данных были выделены следующие варианты повреждения пищевода и его осложнений: интрамуральная гематома пищевода (2); разрыв грудного отдела пищевода без развития гнойных осложнений (2); разрыв грудного отдела пищевода, осложненный развитием медиастинита (4); разрыв грудного отдела пищевода с развитием медиастинита и эмпиемы плевры (13); разрыв шейного отела пищевода, осложненный флегмоной шеи и нисходящим медиастинитом (4). Для каждого варианта была использована различная тактика ведения пациента. Таким образом, выбор и очередность минимально инвазивных вмешательств, таких как торакоскопическая санация средостения и плевральных полостей, стентирование пищевода, наложение чрескожной эндоскопической гастростомы и эндоскопической вакуумно-аспирационной системы, проводились с учетом КТ-данных, в том числе при наблюдениях в динамике.Заключение. КТ при повреждениях пищевода дает возможность получить полную информацию как о характере повреждения пищевода, так и о его осложнениях, определить их вид, локализацию и объем. КТ-данные позволяют обосновать минимально инвазивный подход в лечении повреждений пищевода, определить очередность вмешательств. КТ-исследования, выполняемые в динамике, позволяют оценить эффективность лечения и проводить своевременную коррекцию тактики