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Copyright of Progress in Physics of Metals / Uspehi Fiziki Metallov is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The preparation of ceramic composites based on metal nanopowders allows us to change significantly the thermal characteristics of the ceramic matrix, which is important for the creation of heat-conducting ceramics technology. The work establishes the most efficient method of obtaining nickel nanopowder on a “P-5848” potentiostat by electrolysis of nickel sulfate (NiSO4) with the addition of boric acid (H3BO3), thiourea ((NH4)2CS) and nickel(II) chloride (NiCl2). The synthesis of Ni nanopowder was carried out at a current density from 1.0 to 3.3 A/dm2 and at a temperature of 45–65 °C, where a platinum (Pt) plate was chosen as an anode, and the cathode was specially made of especially pure aluminum (Al). The results of the study showed the synthesis of Ni nanopowder with a size of 55 nm in the form of thin scales. Electrochemical reactions at the cathode and anode are also considered in the work. Several successful experiments were also carried out in the work, which made it possible to develop an economically profitable technology for the synthesis of copper nanopowder by the electrolysis method at 13.3 ampere-hours of current per 1 dm2 of the anode surface at a relatively low temperature of the copper sulfate solution (CuSO4). Copper nanopowder is removed to the bottom of the bath from the anode by impact shaking. An equally successful experiment was carried out, where the cathode was in the form of several copper plates at the distance of 0.8 cm from each other with a voltage between them of 0.775 V, and a current density of 15.3 A/dm2 at the temperature of 54 °С in an electrolyte with 45 % H2SO4, 8 % Na2SO4 and 4 % CuSO4. The work contains tables with initial and final data of all experiments on the synthesis of nanopowders by the electrolysis method. [ABSTRACT FROM AUTHOR]

The review article describes modern fillers of metal and polymer matrices, their properties and applications. We discuss the main parameters of fillers, their advantages and disadvantages, the results of investigations and experiments, which may be useful for scientists and engineers working in the fields of chemistry and materials science and developing new promising materials. Different materials used as the fillers for metal and polymer matrices are reviewed. To create composites of the new generation with improved properties, nanostructured materials such as graphene, fullerenes, nanotubes, nanopowders of metals and their alloys are used. Carbon fil lers can be the strongest graphitizer, which is important for ferrous metallurgy. Nanofillers have the ultradispersed dimensions and high specific-surface values, which allows for changing significantly the physicochemical and functional characteristics of the matrix. As noted in the article, the use of fillers allows controlling the structural composition of the melt and helps to form additional crystallization centres. This, in turn, can affect significantly the properties of the material, such as mechanical strength, heat resistance, etc. [ABSTRACT FROM AUTHOR]

We review and analyse the factors affecting the solubility of interstitial atoms (H) in the metal alloys. The electronic structure and atomic ordering of the AB-type alloys, as well as methods of calculation of the solubility for ordering cubic alloys with octahedral interstitial pores are considered. We study the parameters of interstitial atoms, which make it possible to predict a decrease or increase in solubility, when the main role belongs to the ordering of the system. The parameters of the static distribution of atoms are determined. The relative solubility is represented as a function of the long-range order parameter (η), and the influence of bulk effects on this parameter is considered. The following systems are studied: Fe--Ni, Au--Cu, Pd--Au, Fe--Cr, Ti--Al, Cu--Zn, Ag--Zn, Fe--Al, Au--Ag, Fe--V, Pd--Pt, Ni--Mn, Ni-- Fe, Cu--Au, Cu--Pd, Pd--Nb, Pd--Ag, as well as three-component alloys. As shown, through introducing impurities into the alloy, we can change significantly its physical- mechanical, electrical, magnetic, and other properties. [ABSTRACT FROM AUTHOR]

As part of the work, the hexagonal structure of B19 type metals as hydrogen sorbents will be considered. That is, crystal lattices are considered, where atoms of impurities (hydrogen) are introduced into the interstices of the metal. To do this, we present an image of the B19 structure itself. In this work, the solubility of hydrogen in the crystal structure of B19 type metals was studied using the configuration method, and the dependence on the composition of the alloy and temperature was found in the substitution of nodes and interstices. Also, in the work the degrees of longrange order at the nodes are considered and the parameters of the correlation in the substitution are determined. A graphical view of the effect of atomic order on the solubility of impurities is given. The calculated data obtained in the work coincide with the experimental data of other studies, and the obtained calculation formulas make it possible to determine the energy parameters of the alloys, which is a certain scientific value of the work. The proposed system takes into account only atomic interaction and absorption (dissolution) and diffusion of interstitial atoms into the bulk of the crystal structure; therefore, it is possible to predict the introduction of only a hydrogen atom. Thus, the results obtained in the work of the correlation parameters for the distribution of atoms only in octapores or only in tetrapores allow a deeper study of the physical characteristics of alloys of the B19 type and an understanding of the processes of hydrogen sorption by the working bodies of hydrogen storage. [ABSTRACT FROM AUTHOR]

COVID-19 is a disease caused by the SARS-CoV virus. It stands for severe acute respiratory syndrome, which affects the lungs. The process of replication and progression of the COVID-19 virus causes the formation of an excessive amount of reactive oxygen species and inflammation. Many studies have been carried out that have demonstrated that hydrogen has strong anti-inflammatory properties. It reduces hypotension and other symptoms by reducing inflammation and oxidative stress. Oxygen mixture, enriched with Hydrogen, - helps to reduce the resistance of the respiratory tract and frees up access to the pulmonary alveolus, which improves the penetration of oxygen into the lungs. Since hydrogen is an antioxidant, it helps to reduce the burden on the immune system, helps to maintain the body's health and its ability to quickly recover. When electrolysers are used to produce an oxygen-hydrogen mixture, alkaline mist and other impurities can enter the patient's lungs and cause poisoning and chemical burns. For this reason, the use of atomic hydrogen obtained from metal hydride sources for ventilation of the lungs will be more effective for treating COVID-19 than a molecular hydrogen-oxygen mixture from an electrolyzer. A functional diagram of a metal hydride source of atomic hydrogen to an artificial lung ventilator is shown. It is possible to create a series of hydrogen storage tanks of various capacities., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.)