—Silicon and its composites are widely used to manufacture new electrochemical devices for energy conversion and storage. Current research is being actively conducted and aimed at developing methods ...for the preparation of micro- and nanosized silicon from molten salts. Therefore, the basic regularities of silicon electrodeposition on glassy carbon from the KCl–CsCl–K
2
SiF
6
melt at a temperature of 690°C are studied by cyclic chronovoltammetry and square-wave voltammetry. The electroreduction of silicon ions on glassy carbon under experimental conditions is shown to proceed in one electrochemically reversible four-electron stage. The formal kinetic parameters of the electroreduction of silicon ions under the nonstationary polarization conditions are determined. The diffusion coefficient of electroactive silicon ions is estimated by the Berzins–Delahay equation for an electrochemically reversible process and is equal to 2.75 × 10
–5
cm
2
/s. Silicon is electrodeposited on glassy carbon in the galvanostatic mode at a cathodic current density of 25 and 50 mA/cm
2
. As a result, deposits of fibrous morphology with the average diameter from 0.12 to 0.80 μm are formed.
We investigated the incidence of 15 respiratory viruses among 2991 children with acute respiratory infections in Novosibirsk city, Russia, prior to the COVID-19 pandemic (2013–2020). Viral infections ...were detected in 72.5% cases. The incidence of human coronavirus was 2% (Alphacoronaviruses, 63%; Betacoronaviruses, 37%).
Demand for satellite reconfigurability Andreev, A S; Leonova, A V; Popov, A M
IOP conference series. Materials Science and Engineering,
04/2020, Letnik:
822, Številka:
1
Journal Article
Recenzirano
Odprti dostop
This article analyzes several approaches to in-orbit satellite reconfiguration: rapid launch, reconfigurable satellite constellations, modular satellites and software defined radio. A number of ...significant projects are studied under each category. Software defined satellites is selected as the most promising technology.
Nano- and micro-dimensional surface layers of titanium on flat and wire NiTi substrates were obtained. The structure and composition of the samples was determined using SEM, AES, Auger spectroscopy ...and X-ray diffraction. With increasing deposition time, the thickness of the surface layer increases nonlinearly. The transition layer provides high adhesion of the surface layer to the substrate.
This review focuses on recent experimental data obtained by site-directed mutagenesis of the reaction center in purple nonsulfur bacteria. The role of axial ligation of (bacterio)chlorophylls in the ...regulation of spectral and redox properties of these pigments, as well as correlation between the structure of chromophores and nature of their ligands, are discussed. Cofactor ligation in various types of reaction centers is compared, and possible reasons for observed differences are examined in the light of modern ideas on the evolution of photosynthesis.
Modern sustainable formation of land management of territories in the Russian Federation among other things has a significant environmental aspect, the role of which increases every year in the early ...2020s. Formation of a qualitative sustainable ecological state of the state requires the maintenance of qualitative and qualitative accounting, actual monitoring of the state of land in the Russian Federation. The article considers and analyzes the current order of the real estate cadaster in the Russian Federation from the point of view of the formation of a sustainable ecological state of the land of the state and its direct relationship in the current system of accounting and environmental monitoring of land according to the current regulations. The analysis of the role of improving the environmental component of land management and real estate cadaster in the context of monitoring and evaluation of systematic analysis of incoming information in terms of the practical component of the implementation of such information. The role of environmental studies for the formation of criteria and quality level of works on land management and real estate cadaster is assessed. Key words: state cadastral registration of real estate, unified state register of real estate, inventory of real estate objects, environmental monitoring of lands, cadastre, real estate, register, environmental legislation, accounting, law.
The aim of this paper was to assess the man-made risks arising in the process chain from the extraction of primary raw materials in the form of quartzite and its further processing into the final ...product in the form of silicon. As the objects of research, we chose quartzite extracting enterprises, Cheremshansk Quartzite Mine and Kremny JSC which processes quartzite into silicon. To assess the occupational risk, we applied the method of assessing the individual occupational risk (IOR) level developed by the Klin Institute of Occupational Safety and Working Conditions. As a result, it was established that, in general, the level of occupational risks in the extraction of quartzite corresponds to the "average" level of risk. The occupation of Screener was classified to have the highest level of IOR (0.2). For the most part, a significant contribution to the level of occupational risk for the considered occupations is made by the dust factor, as well as - for the occupations connected with the steering of large-sized machines - by general vibration. In the processing of quartzite, the IOR level corresponds to the "average" level of risk in most occupations. However, for some of the workers, the risk level is set to the "high" value. This is due to significant concentrations of dust in the air of the working area, as well as unfavorable microclimate parameters.
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