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The article discusses the influence of technological parameters of sulfur electrodes and the concentration composition of the salt-solvation electrolytes TEGDME–LiTFSI on the specific characteristics of Li-S cells obtained under galvanostatic cycling conditions. The dependences of the specific capacity on the composition of the cathode, the charge-discharge current density, as well as capacity retention upon storage are discussed.

The electrochemical properties of LiMn2O4 surface modified with LiNi0.5Mn1.5O4 at different current densities are presented. The electrode with a maximum percentage of covering (14% of LiNi0.5Mn1.5O4) can endure higher current loads compared with the sample consisting 7% of surface layer. The capacity values for these samples at 45° and 30°C are 22 and 31 mAh∙g-1, respectively. This means that the proposed approach can be an effective tool for obtaining electrode materials for high-rate applications.

Translational GTPases (trGTPases) belong to the family of G proteins and play key roles at all stages of protein biosynthesis on the ribosome. Unidirectional and cyclic functioning of G proteins is ensured by their ability to switch between the active and inactive states due to GTP hydrolysis accelerated by the auxiliary GTPase-activating proteins. Although trGTPases interact with the ribosomes in different conformational states, they bind to the same conserved region, which, unlike in classical GTPase-activating proteins, is represented by ribosomal RNA. The resulting catalytic sites have almost identical structure in all elongation factors suggesting a common mechanism of GTP hydrolysis. However, fine details of the activated state formation and significantly different rates of GTP hydrolysis indicate the existence of distinctive features upon GTP hydrolysis catalyzed by the different factors. Here, we present a contemporary view on the mechanism of GTPase activation and GTP hydrolysis by the elongation factors EF-Tu, EF-G, and SelB based on the analysis of structural, biochemical, and bioinformatics data.

The paper presents structural, surface, thermodynamic and kinetic characteristics of titanium dioxide samples obtained by means of alkaline hydrolysis of TiCl4 by LiOH solutions and further heat treatment. TiO2 samples have the anatase structure with crystallite size of 7–10 nm. An increase in the heat treatment temperature from 150 °C to 470 °C leads to a decrease in the specific surface area from 404 to 80 m2/g and the total pore volume from 0.340 to 0.152 cm3/g. The influence of electrolyte composition and surface properties of TiO2 on its behavior in cells with lithium anode investigated by means of galvanostatic cycling and impedance spectroscopy is discussed.

The most Important areas of the preventive role of criminal law are limiting the use of punishment in the form of deprivation of liberty, determining legal compromises between the offender, the victim, society and the state, establishing an effective system of punishment, fair sentencing, which is as individualized as possible, and others. In this regard, criminal justice takes place after the commission of crime through the implementation of the preventive function of criminal law norms. Today, an urgent problem is the study of criminal law crime prevention, as a collective, complex concept that includes the possibilities of criminal and penal law. This study is devoted to the prevention of crimes by criminal law means. The paper explores the problems of manifestation of the preventive function of criminal law in the application of punishment and other forms of criminal responsibility, justifies the position on reducing the imposition of convictions with a penalty of imprisonment. The analysis of current legal acts and opinions of scientists who conducted research in this area is carried out.

Atom probe tomography (ATP) is a technique that has actively been developed in recent years. This method allows one to investigate three-dimensional distributions of chemical elements in various materials with atomic spatial resolution. The raw APT data reconstruction algorithm uses the geometry of evaporated ion trajectories. However, the basic algorithm uses the approximation of rectilinear trajectories of ions moving from the specimen to the detector. In this study, we present the main approaches to adapting and optimizing the basic APT data reconstruction algorithm concerning the mass reconstruction procedure. Methods for taking into account the nonlinear distortions of ion trajectories due to the wide-angle detection system and other features of ion detection in atom probe tomography are demonstrated. Using a titanium alloy (Ti—5Al—2.7Mo—2Zr), we demonstrate that the consideration of the above effects in the reconstruction of ATP data makes it possible to increase the mass resolution, m/Δm50%, of the main peaks of the mass spectrum to 600 and above. In general, the set of performed procedures allows one to achieve a high accuracy of the positioning of the peaks up to 0.01 amu and ensures a significant (more than tenfold) increase in the mass resolution for mass spectrum peaks that are distant from the main peaks.

In this paper, we obtained analytical equations for electrostatic fields of two-dimensional planar and axially symmetric mirrors with piecewise-constant and piecewise-linear potentials on electrode surfaces located symmetrically in parallel planes or on a cylindrical surface, in particular, in the presence of an additional end electrode. The results can be used for the efficient optimization of aberration properties of time-of-flight mass analyzers and electrostatiс ion traps with gridless ion mirrors based on both standard planar or ring-type electrodes with finite gaps between them and PCB plates.

Lithium-manganese-rich–lithiated nickel-manganese-cobalt oxides are advantageous for using in lithium-ion batteries due to low toxicity and high specific capacity but suffer from low high-rate capability. In this paper, characterization and electrochemical testing of 0.5Li2MnO3·0.5LiNi0.5Mn0.3Co0.2O2 (Li1.2Ni0.2Mn0.52Co0.08O2) obtained by means of a citric acid–aided route is described. It demonstrates excellent electrochemical performance possessing specific capacity equal to the theoretical value (280 mAh g−1), being able to be discharged with currents of 2240 mA g−1 (8 C), having high coulombic efficiency (~ 99%) even after high-rate tests, and manifesting low capacity fade after high current loads and upon further cycling by 0.1 C currents (0.144 mAh g−1 per cycle).

Commercial thermoplastic plasticized polymer films based on polyvinyl acetate of different chemical compositions and composite metal-viscoelastic polymer film-metal three-layer materials were studied by dynamic mechanical analysis. The dependences of the mechanical loss coefficient and elastic modulus of polymer films on temperature and strain frequency at dynamic extension were determined experimentally. The temperature intervals of efficient damping were determined. In these intervals, the mechanical loss coefficient of each polymer film exceeds 0.5 for the frequency range 1–10 000 Hz. The dissipative properties of polymer films and composite materials based on them were compared. The mechanical loss coefficients of the films materials are higher than those of the composite materials, but the composite materials have higher mechanical loss moduli. Their absolute values at the maximum-damping temperature reach ∼1011 Pa and more, which allows using them as effective vibration-damping coatings.

High-rate electrochemical systems as well as materials and electrolytes for such systems are briefly described. An optimized citrate method is presented for the synthesis of nanosized electrode materials with electrochemical properties comparable to the properties of the best commercial samples. Possible criteria for an ideal electrode material are formulated and the theoretical high-rate limit of such material is estimated. Dynamic criteria are proposed to identify the specific species in the electrolyte solutions and the most efficient charge transfer is shown to be carried out by solvent-separated ion pairs.

The article describes methods for the formation and presentation of digital images of objects of various types (printed publications, archival materials, museum items, audio-video materials) for the electronic library «Scientific Heritage of Russia».

Teniz-Korgalzhyn lakes are included in the list of Ramsar sites of international importance and are a place of concentration of a huge number of waterfowl and near-water birds. These are more than 60 fresh and salt lakes with a depth of 1-4 m. Changing the area of the water surface of lakes leads to a change in habitat conditions, species composition and number of birds. The article shows that the changes are associated with both natural and anthropogenic factors. The possibility of studying the dynamics of the area of lakes based on the methods of geoinformation analysis and remote sensing is considered. Several methods have been tested for calculating the area of the water surface of lakes using multizonal space images using specialized spectral indices. On the example of 18 lakes for each method, the mean square error of the accuracy of the results obtained was calculated. It is shown that for the study area the most reliable result is given by the modified normalized water index MNDWI. On its basis, the interannual dynamics of the area of the water surface of the Teniz-Korgalzhyn lakes for the period from 2006 to 2019 was analyzed. It is shown that the fluctuation of the total area of the water surface of the largest lakes during this period reached 2.5 times. At the same time, the trend towards a gradual increase in the area of freshwater lakes since 2013 is primarily due to the action of natural and climatic factors. A much more significant increase in the area of the salt lakes Big and Small Teniz is due to the additional inflow of water due to the breakthrough of the Tabiyak dam in 2015.

We study the interplay of global attractive coupling and individual noise in a system of identical active rotators in the excitable regime. Performing a numerical bifurcation analysis of the nonlocal nonlinear Fokker–Planck equation for the thermodynamic limit, we identify a complex bifurcation scenario with regions of different dynamical regimes, including collective oscillations and coexistence of states with different levels of activity. In systems of finite size, this leads to additional dynamical features, such as collective excitability of different types and noise-induced switching and bursting. Moreover, we show how characteristic quantities such as macroscopic and microscopic variability of interspike intervals can depend in a non-monotonous way on the noise level.

Рассматриваются вопросы анализа перспективных методов кодирования и манипуляции группового телеметрического сигнала в современных бортовых системах видеоконтроля, устанавливаемых на сложных технических объектах. Целью работы является оценка эффективности бортовых систем видеоконтроля на основе анализа перспективных методов кодирования и манипуляции группового телеметрического сигнала. Проведено сравнение современных бортовых систем видеоконтроля по критериям вероятности битовой ошибки, значения ширины полосы Найквиста и обеспечения энергетической эффективности.

The Volga-Akhtuba floodplain is a unique intrazonal ecosystem of the Lower Volga. For many years, the landscapes of the area suffered from an intensive anthropogenic impact, starting with the commissioning of the Volga Hydroelectric Power Plant. Increasing anthropogenic pressure, high ecological value and standing out against the background of semi-desert areas led to the inclusion of this area into the Volga-Akhtuba Floodplain Nature Park in 2000. This article analyses the changes in the functional zoning of the nature park at the beginning of active conservation activities and present. The authors reveal the main hotspots of economic activity represented by agriculture in the region and farmsteads, which include settlements, horticultural societies and their linear infrastructure (road and transport network). In addition, they identify forest ecosystems of particular ecological and aesthetic value. The analysis of the economic impact and distribution of unique forest ecosystems provides an assessment of the changes in the spatial organisation of the area.

1 M solutions of NaClO4 mixed with ethylene carbonate, dimethyl carbonate, and fluoroethylene carbonate were studied as electrolytes for a double-layer supercapacitor with electrodes made of Norit DLC Supra 30 activated carbon. It was shown that the specific capacity of activated carbon depends on the electrolyte composition, range of cycling voltages, and current density. The maximum specific capacitance of 40 F g–1 was obtained in 1 M NaClO4 mixed with ethylene carbonate: dimethyl carbonate: fluoroethylene carbonate (4: 5: 1) at a current density of 36 mA g–1 in the range 10–2300 mV. The minimum specific capacitance was obtained under the same cycling conditions in the electrolyte with 1 M NaClO4 + ethylene carbonate: dimethyl carbonate (1: 1). The variation of the specific capacitance with the electrolyte composition and range of cycling voltages is accounted for by the existence of a pseudocapacitance caused by the occurrence of side processes on the surface of activated carbon. The impedance spectroscopy was used to find that the introduction of fluoroethylene carbonate into the electrolyte positively affects the charge-transfer resistance and favors an increase in the specific capacitance of activated carbon.

Citrate precursors of copper, nickel and cobalt oxides, namely Cu(C6H7O7)2·5H2O, Ni(C6H7O7)2·2.5H2O and CoC6H6O7·6H2O, have been synthesized from solutions with metal to citric acid ratio of 1:2, their thermal decomposition has been studied, and decomposition products have been analyzed. It has been found that the Cu salt loses water and then forms acidic aconitate and acidic itaconate, which then transforms to normal itaconate and further to CuO. The Ni salt dehydrates and decomposes directly to normal itaconates and then to NiO mixed with Ni metal. The Co salt dehydrates and then transforms to normal aconitate, normal itaconate and to Co3O4 containing CoO. While the oxides in question form crystallites of 15–25 nm size with pores of around 3–4 nm in radii, their morphology differs significantly. CuO particles are nanosized. Unlike them, NiO and Co3O4 develop aggregates of approx. 300–500 nm size. Similarities and differences in decomposition processes and morphology of the target oxides are analyzed and discussed, and possible improvements of the citric acid-aided route are suggested. It is shown, in particular, that the formation of metallic Ni and CoO is predetermined by thermodynamics of redox processes involving oxygen and carbon monoxide obtained by the decomposition of the organic part of precursors.

Being widely considered a powerful tool for improving the capacity retention and rate capability of cathode materials for lithium-ion batteries, surface modification has never been applied for obtaining truly high-rate spinels. The stoichiometric LiMn2O4 and a material containing the LiMn2O4 core and LiNi0.5Mn1.5O4 shell with the shell/core mass ratio of 0.1:1 have been synthesized by means of a citric acid aided route. The samples studied have been characterized using thermal analysis, X-ray diffraction and scanning electron microscopy. The specific discharge capacities of LiMn2O4/LiNi0.5Mn1.5O4 and LiMn2O4 at I = 0.5C equal to 107 and 110 mAh g−1, respectively. The surface coated LiMn2O4/LiNi0.5Mn1.5O4 shows up an exceptional high-rate ability being able to retain ca. 25 mAh g−1 at the current load of 9620 mA g−1 (65C), which is 1.625 times higher than for the unmodified LiMn2O4. Such exceptional high-rate properties and better cycling ability of the core-shell LiMn2O4/LiNi0.5Mn1.5O4 compared to parent compounds prove good prospects of surface modification techniques in improving rate capabilities of spinel materials.

Еlectrochemical performance of Co 3 O 4 in lithium-ion batteries is briefly reviewed. Co 3 O 4 samples are synthesized via microwave-assisted solid state and citric acid aided methods. It is shown that the latter method leads to disperse nanosized materials having discharge capacity close to the theoretical value. Several electrolytes are probed so as to minimize capacity losses upon cycling, and the one containing lithium bis(trifluoromethane)sulfonimide in a mixture of fluoroethylene carbonate and dimethyl carbonate is selected. High-rate tests reveal that capacity retention of the samples obtained is well comparable with the best existing data, and at the current load of 5340 mA g −1 (6C) all materials studied retain more than 50% of initial capacity.

Overdischarge poses a significant threat to the safety and reliability of lithium ion batteries. In this paper, overdischarge (overlithiation) effect on electrochemical parameters of lithium manganese spinels of different origin is studied. Charge/discharge tests for 240 cycles are performed within recommended and lowered potential ranges. Insertion of lithium ions into spinels by decreasing potential to either +2.4 or +1.5 V against Li/Li+ is found to lead to the formation of the overlithiated Li2-x Mn2O4 spinel phase. Repeated cycling involving the low-potential regions worsens electrochemical parameters: cell resistance increases and specific capacity decreases. It appears that even small overdischarge is totally unacceptable for the nanosized home-made samples and microsized EQ–Lib–LMO (MTI) samples. The microsized BE–30 (NEI) sample better tolerates cycling at lowered potentials. The greatest resistance to overdischarge demonstrates the aluminum-doped microsized HPM–9051C (Toda) sample. Being treated at lowered voltages, this material acquires a steady trend towards an increase in specific capacity by half. This may signify that at least half of the gram equivalent of extra lithium ions can be electrochemically inserted into the 16с voids in the spinel structure resulting in the Li1.5Mn2O4 compound, which is able to reversibly work within the 2.4–4.6 V potential range.

The results of development, creation, and tests of an atom-probe prototype with femtosecond laser evaporation and a position-sensitive microchannel detector with delay lines for the tomographic (3D) analysis of chemical composition of materials are presented. The atom-probe tomography is based on the principle of atom-by-atom “disassembling” of materials and projection magnification, which was previously used in field-ion microscopy, as well as the time-of-flight mass spectrometry that is applied to each evaporated ion. The prototype characteristics (mass resolution, spatial resolution, and data-collection efficiency) were demonstrated in study of tungsten.

Anthropogenic air pollution attracts attention of scientists and the public around the world for many years. Traveling over vast distances, particles and aerosols pollute the environment many kilometers away from emission sources. Primary anthropogenic aerosols enter the air mainly with industrial emissions from factories. Secondly aerosols are formed in the atmosphere through various physical and chemical processes involving water vapor, organic compounds, etc. This group includes sulphur dioxide. The article discusses issues related to the pollution of the environment as a result of the activities of the copper-nickel plant Severonickel, located on the Kola Peninsula. In particular, the problem of accumulation of sulfur compounds in the soil, which occurs over decades at a different distance from the industrial factory. Sulphur dioxide is a toxic substance, at high concentrations in the air there is a harmful impact on living organisms, precipitation leads to acidification of the soil, disturbance of soil and vegetation cover, changes balance and destroy ecosystems. For this reason, it is important to monitor the condition of ecosystems that are under the influence of industrial plants. This issue is dedicated to the work of researchers and students of the Department of Environmental Management of the Faculty of Geography of Lomonosov Moscow State University, who for more than twenty years have been monitoring the state of ecosystems in the impact zone of Severonickel plant, including a number of studies devoted to pollution of the soil with sulfur compounds.