bluuebunny/crossref_metadata_2025_split huggingface dataset:
The form of the elastic core and areas of plastic flow base under the jucked stamp
Authors: Bogomolov A N , Bogomolova O A 
Published: June 2021

Abstract
The article provides the information about studies devoted to determining the position, shape and size of the elastic soil core and areas of plastic deformations formed in the soil foundation under the jucked stamp. Based on the results analysis of experiments carried out by third-party researchers and the results of calculations performed by the authors of the article, it was concluded that an elastic soil core in the form of a triangle is formed in the case when the indentation of a stamp is carried out into a base folded with loose ground, provided that φ>25-30° (this depends on the value of the lateral soil pressure coefficient), and the specific cohesion C is quite small. In cohesive soils, the vertical section of the elastic soil core has a form close to that of half an ellipse, half or a segment of a circle. The exceptions are the results of the experiments by Kaganovskaya S E, where a triangular elastic core was obtained for clay soil. All these facts are in satisfactory agreement with Prandtl’s design scheme, and therefore, the use of calculation methods based on it is justified only for sandy bases. To solve the problem of calculating the bearing capacity of soil foundations composed of various types of soils, methods should be created that are not based on hypotheses about the shape of the elastic core and areas of plastic deformation.
New pile foundation structures for swelling clay soils
Authors: Gabibov F G 
Published: June 2021

Abstract
The information on the basics of designing pile foundations on swelling clay soils is presented and analyzed. New designs of conical piles and those with a variable cross-section, in which the soil mass swelling is accompanied by the effect of pile pinching, have been developed. Moreover, new pile foundation structures with protective shells involving a calcium elastic rolling member and some rubbing elements like low-friction plastic and metal braces are proposed.
Influence of superplasticizer additive on the strength of cement stone during wetting–drying cycles
Authors: Dobshits L M , Nikolaeva A A 
Published: June 2021

Abstract
This article discusses the issues of durability of reinforced concrete structures exposed to drying–wetting cycles. Transport structures are under the constant wetting and drying cycles, but rarely completely dry out, as the saturation process occurs faster drying. Such cycles cause moisture migration inside the concrete, which leads to leaching of calcium hydroxide Ca (OH)2. The structure of the cement stone changes over time, and the dissolution of cement hydration products additionally leads to a strength decrease. Were tested the influence of the alternation of cycles of water saturation and drying of concrete on tensile strength, as the most sensitive characteristic to changes in the structure of the material. Since at present most concretes are manufactured using plasticizing additives, the tests were carried out with different content. The studies show that regardless of the amount of plasticizing additive in the samples, the flexural strength decreases. The compressive strength gradually increased, which is probably due to the ongoing process of hydration of the cement grains.
Multicomponent complex oxide media – the basics of the functional materials for electronic engineering: the selection of the promising compositions for assessing the ferrohardness
Authors: Andryushin K P , Dudkina S I , Shilkina L A , Andryushina I N , Rudskiy D I , Verbenko I A , Reznichenko L A 
Published: June 2021

Abstract
According to the optimal technological regulations, the solid solutions of two four-component systems based on lead titanate-zirconate and alkali metal niobates were prepared: (1-x) Na0.875Li0.125NbO3 – xPbTi0.5Zr0.5O3 (0.05 ≤x < 0.95, Δx = 0.025-0.10) and (1-x) Na0.875K0.125NbO3 – xPbTi0.5Zr0.5O3 (0.0 ≤x ≤1.0, Δx = 0.05-0.10). The electrophysical parameters of the solid solutions of these systems were determined and the degree of their ferrohardness and efficiency was assessed according to the main characteristics: the relative permittivity of the polarized samples, ε33T/ε0, the mechanical quality factor, Q
M, the coefficient of electromechanical coupling of the radial vibration mode, Kp, the piezomodule, |d
31|. It was shown that, depending on the chemical composition and the position of the solid solutions on the phase diagram of the systems, they can be characterized by different degrees of the ferrohardness and efficiency, which made it possible to select promising compositions: ferrohard ones – for the converters with high specific power (in step-down piezotransformers, piezoelectric motors, etc.) ); of the medium ferrohardness – for highly sensitive receivers of the ultrasonic vibrations (telemetry sensors, automatic control systems, etc.); ferrosoft materials with high efficiency – in the low-frequency devices (microphones, hydrophones, deflectors of the optical systems, robotics devices, etc.).
Structural, elastic and thermal properties of Laves phase Fe2Mo from first principles
Authors: Vasilyev Dmitry 
Published: June 2021

Abstract
In this work, structural, elastic and thermal properties of the Laves phase Fe2Mo (λ-) with the C14-type structure existing in the Fe – Mo system have been investigated using the quantum mechanical calculations within the frame of the density functional theory (DFT). The equilibrium lattice parameters, atoms position coordinates and average magnetic moment of atoms were calculated. The five independent elastic constants of the strain tensor were calculated by imposing small strains on the crystal lattice. Polycrystalline elastic parameters: bulk modulus (B), shear modulus (G), Young’s modulus (E), and Poisson’s ratio (v) were obtained by using the Voigt-Reuss-Hill (VRH) approximation. An assessment of anisotropy of elastic properties was carried out. The Debye temperature and anisotropic sound velocities were predicted. The calculated results were analyzed. The obtained results are useful to improve the understanding of the physical and chemical nature of the Fe2Mo phase.
Experimental study of plasticization and foaming of polymer materials in supercritical carbon dioxide
Authors: Minaeva S A , Epifanov E O , Minaev N V , Popov V K , Zimnyakov D A 
Published: June 2021

Abstract
A laboratory system for the development of new approaches to the experimental study of nucleation and formation of three-dimensional structures in nonequilibrium “polymer-supercritical fluid” heterogeneous systems has been designed and produced. The system is designed to conduct a comprehensive analysis of these processes at various stages starting from supercritical fluid plasticization of the initial polymer, followed by its subsequent nucleation and passage to the glass transition stage of the foamed polymer matrix, providing an opportunity for adequate interpretation.
Development of photometric analysis of structural images in relation to the study of nickel-chromium alloy
Authors: Ermishkin V A , Mikhailov D L , Minina N A 
Published: June 2021

Abstract
This work presents preliminary results of the study of a new nickel-chromium corrosion-resistant alloy “Solution-N” intended to replace the imported G-35 alloy, which is currently used for the manufacture of chemical reactor vessels. In view of the limited amount of smelted material, photometric analysis of structural images is widely used to study its structure and properties. Based on the results of the studies carried out, it is proposed to choose the optimal structural state of the alloy, which has the highest corrosion resistance in the temperature range 600-650°C. Corrosion tests are currently being carried out in the laboratory of the prospective customer.
Dielectric spectroscopy, piezoelectric and ferroelastic properties of solid solutions of the three-component system (1-x-y) NaNbO3 – xKNbO3 – yCdNb2O6 in the temperature range (10-330) K
Authors: Moysa M O , Andryushin K P , Kubrin S P , Andryushina I N , Reznichenko L A 
Published: June 2021

Abstract
A solid solution of the three – component system 0.8NaNbO3 – 0.15KNbO3-0.05CdNb2O6 was prepared by two-stage solid-phase synthesis followed by sintering using conventional ceramic technology. An experimental study of the dielectric, piezoelectric, and ferroelastic characteristics of the latter in the low-temperature range (10÷330) K. The conclusion is made about the expediency of using the obtained results in the development of functional ferroactive materials based on sodium – potassium – cadmium niobates and devices with their participation.
Influence of the sintering temperature on morphology of alloy germanium-tin nanoparticles synthesized by spark discharge
Authors: Lizunova A A , Borisov V I , Ivanov V V 
Published: June 2021

Abstract
Alloy GeSn airborne nanoparticles (NP) with the rate of atomic content of Sn to Ge 30 % were produced by spark discharge during simultaneous erosion of germanium and tin electrodes in atmosphere of argon of purity 6.0. Then NP were moved by gas flow to a tube furnace, which were mounted directly after discharge chamber, and sintered at temperatures from 25 to 750 °C. The change of morphology, element composition and crystal structure of NP were investigated using transmission electron microscopy (TEM) with energy dispersive X-ray analysis (EDX), aerosol spectrometer and Fourier-transform infrared spectroscopy (FTIR). Agglomerates of predominantly amorphous primary NP with the mean size of 7 nm were obtained at low sintering temperatures of the tube furnace (25 and 200 °C). High temperature (550 and 750 °C) flow-through thermal sintering of NP agglomerates resulted in production of individual crystal NP with an average size of 28 nm with various crystal structures.
On the diagnostic features of the gas-discharge visualization for the assessment of medicines
Authors: Shipko M N , Sibirev A L , Maslennikova O M , Stepovich M A , Nikonorova V G 
Published: June 2021

Abstract
The therapeutic efficiency of medicines containing the same active ingredient depends on the production technology, as well as the excipients included in the tablet and the type of shell. In this work, we consider some of the possibilities of using the gas-discharge visualization method based on the phenomenon of channeling electrons through a liquid medium to study aqueous solutions of medicines. The study was carried out on the example of the passage of kilovolt electrons through drops of solutions of the beta-blocker bisoprolol, produced by various pharmacological companies. We studied bisoprolol preparations without excipients and bisoprolol preparations with excipients. The obtained differences in the characteristics of the gas-discharge luminescence for the studied medicines open up prospects for assessing the quality and pharmacological efficiency of medicines, and, subsequently, for the individualization of medicines therapy.
Phases formation in cerium-doped hydroxyapatite
Authors: Petrakova N V , Nikitina Yu O , Egorov A A , Titov D D , Baranov O V , Barinov S M , Komlev V S 
Published: June 2021

Abstract
Cerium-substituted hydroxyapatites (Ce-HAs) with an estimated content of Ce3+ of 0; 0.1; 0.25; 0.5 mol. % were prepared by two different synthesis methods: precipitation from aqueous solutions of salts and mechanochemical synthesis. The powders after synthesis were heat-treated at 1250 °C to achieve well-crystallized phases. The X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), energy dispersive analysis (EDA), and dilatometry methods revealed that cerium ions didn’t not fully incorporate into the HA structure, but rather were transform to the CeO2 phase. It was attributed to the transition of Ce valency (III)→(IV) through the oxidation reaction under air conditions during materials heating. Two different synthesis methods provided similar phase composition of the obtained compounds, though different microstructure of the resulted ceramics. It was shown that cerium introduction prevents HA sintering during thermal activation, possibly due to contribution of large atomic mass of cerium ions and formation of cerium (IV) oxide at the crystal boundaries.
Si3N4 ceramics with sintering additive of MnO-TiO2
Authors: Kim K A , Lysenkov A S , Titov D D , Petrakova N V , Frolova M G , Ivicheva S N , Fedorov S V , Kargin Yu F 
Published: June 2021

Abstract
Ceramic samples based on Si3N4 were obtained and studied using a sintering additive in the MnO-TiO2 system of eutectic composition, which was accepted and applied to the surface of silicon nitride by the sol-gel method. Ceramic samples were obtained by hot pressing at 1650 °C and 1750 °C. Phase composition, thermo-physical and mechanical properties were studied. The microstructure of the resulting ceramics was also studied.
Sintering and properties of materials based on nanosized silicon nitride powder
Authors: Tomkovich M V 
Published: June 2021

Abstract
A high-density material (ρ = 3.28 g / cm3, porosity 1.4% by volume) based on nanosized silicon nitride powder was obtained by the method of liquid-phase sintering. The effect of compacting pressure on the density of sintered silicon nitride materials is shown. The process of material structure formation during sintering has been studied. The main physical and mechanical characteristics were determined: density, porosity and grain size of the solid phase, elastic modulus, flexural and compressive strength, crack resistance coefficient, Vickers hardness.
The impact of a sintering additive from Al, Mg, Y-oligomer on the physicochemical properties of MoSi2 ceramic
Authors: Danilin K D , Titov D D , Lysenkov A S , Kargin Yu F , Konovalov A A , Petrakova N V , Gumennikova E A , Senina M O , Shcherbakova G I 
Published: June 2021

Abstract
We investigated the effect of a triple oxide additive (Al2O3-MgO-Y2O3) obtained by a new method on ceramics properties based on MoSi2. The ternary oxide was obtained from a ceramic-forming oligomer. Ceramic MoSi2 samples were obtained by hot pressing of molybdenum disilicide with ternary oxide 1, 3, 5, 10 wt% at 1650 °C and 30 MPa. The graphs of the dependence of density, bending strength and electrical resistance on the content of Al2O3-MgO-Y2O3 are presented. It was found that as the additive level was increased, the flexural strength increased to 89 MPa. The specific electrical resistance, depending on the oxide additive content, is extreme with a maximum for a composition containing 1 wt% Al2O3-MgO-Y2O3.
Structural features of metals and alloys formed in the process of selective laser melting
Authors: Bazaleeva K O , Tsvetkova E V 
Published: June 2021

Abstract
The features of the structure formed during selective laser melting (SLM) on the example of austenitic steel Fe-17%Cr-12%Ni-0.02%C (316L) and nickel alloy Ni-11%Cr-5%Co-6%Al-3%Ti-4%Mo-5%W-0.16%C-0.02%B are considered in this work. The structure formation occurs under conditions of ultrafast cooling rates from the region of the melt during laser treatment and subsequent thermal cycling during solidification of material adjacent regions. The following structural features are considered: hierarchical structure, heterogeneity of the alloying elements distribution, dislocation structure, macrostresses and crystallographic texture.
Effect of the synthesis temperature on the phase composition of Al2O3
Authors: Leonova Yu O , Sevostyanov M A , Mezentsev D O , Khayrutdinova D R , Lysenkov A S 
Published: June 2021

Abstract
This work is devoted to studying the effect of the synthesis temperature on the phase composition of Al2O3. Aluminum hydroxide was obtained by a reverse heterophase deposition method. This method makes it possible to obtain the purest hydroxide powder. For the synthesis, several different temperature regimes were selected in the temperature range from 250°C to 1100°C.
Non-traditional legumes in the soil-protecting crop rotation of the mountain zone of the Republic of North Ossetia-Alania
Authors: Tedeeva A A , Mamiev D M , Abaev A A , Tedeeva V V 
Published: June 2021

Abstract
Mountainous and sloping lands occupy one third of the territory of our country, more than 50% in the Republic of North Ossetia-Alania, and are a huge reserve for increasing agricultural production. Soil and climatic conditions on the slopes of the mountains and in the intermountain valleys make it possible to grow environmentally friendly products, to heal the seeds of agricultural crops from viral diseases. Increasing the production of agricultural products is one of the most important problems of agriculture. The mountainous territory of the Republic of North Ossetia-Alania is an important reserve for increasing the volume of agricultural production. About forty percent of the total area of the republic is concentrated here, most of which is characterized by favorable soil and climatic conditions. The development of agrotechnical, anti-erosion measures is one of the factors of preventing erosion processes in the soil and restoring soil fertility. The research was carried out in a mountainous area on mountain-meadow soils. According to the mechanical composition, it is middle loamy. The soil contains a high level of organic matter. It is moderately provided with hydrolyzable nitrogen and mobile phosphorus, and is highly provided with potassium. Studies have shown that these soils are favorable for the cultivation of perennial non-traditional leguminous grass species-eastern galega and crown vetch and the obtaining of products with high feed rates. The greatest soil protection effect from water erosion in the crop rotation was possessed by perennial leguminous grasses cultivated on a herbage – clover with timothy, eastern galega and crown vetch, which have a coefficient of soil protection from water erosion. In the soil-protecting six-field crop rotation eastern galega and crown vetch improved the structural and aggregate composition of the soil, the water resistance of soil aggregates, density and pore volume, also they increased soil fertility.
The use of herbicides in the cultivation of corn
Authors: Tedeeva A A , Mamiev D M , Tedeeva V V , Khokhoeva N T 
Published: June 2021

Abstract
The article discusses the results of studying the effectiveness of the use of new generation herbicides, both soil, applied before the emergence of maize seedlings – Merlin (150 g/ha); Cassius (50 g/ha), and for seedlings – Elumis (1.0-2.0 l/ha), on crops of three maize hybrids. The studies were carried out in the conditions of the foothill zone of the Republic of North Ossetia-Alania, on leached chernozems. The objects of research were different corn hybrids in terms of precocity (the originator of the KBNIISKH).) – Kabardinskaya 3812 (late-repining), Camilla SV (mid-late), a variety of white-grain food corn Bella 451, which is cultivated not only to obtain varietal seeds, forage, but also to meet the food needs of the indigenous population. The national cuisines of most of the peoples of the North Caucasus use flour and cereals made from white-grain corn. In this regard, it is very important to introduce into production, along with yellow-grain forms used for fodder, highly productive varieties and hybrids of white-grain corn for food purposes. Middle-late variety, food grade. As a result of the conducted studies, it was found that the treatment of the soil with the herbicide Elumis was more effective than the check. We had the following grain yield: Kabardinskaya 3812 hybrid – 8.7 t/ha, on the nonfertilized ground, 12 t/ha – on the fertilized ground, Camilla SV hybrid – 8.5 t/ha – on the nonfertilized ground, 11.7 t/ha – on the fertilized ground, and Bell 451 hybrid – the yield on the nonfertilized was 7.0 t/ha, on the fertilized ground – 9.9 t/ha. The response in yield of Kabardinskaya 3812 hybrid to the application of herbicides was more effective than other hybrids studied.
Development of a method for testing the wear resistance of friction pairs based on the synthesis of the method of M. V. Lomonosov with the improved method of artificial bases
Authors: Davydov R V , Tikalov A V , Chulkin S G , Breki A D , Efremov L B , Rud’ V Yu , Bykova N N , Valiullin L R 
Published: June 2021

Abstract
The article is devoted to improving the method of testing the wear resistance of friction pairs in a wide range of hardness by embedding a roller into a flat surface of the material under study (sample), first proposed by M. V. Lomonosov. The formula for estimating the volumetric wear resistance from linear depending on the specific pressure is proved. According to the new method, the relative wear resistance of materials in a wide hardness range was evaluated.
Socio-ecological consequences during the construction of a multistage system of flood control facilities on side tributaries
Authors: Podgornov N S , Davydov R V , Zotov D K , Antonov V I , Maslikov V I , Maslikova E I , Chusov A N , Cheremisin A V 
Published: June 2021

Abstract
A method of protecting territories in a river basin during flash floods by creating a multi-stage system of intercepting flood control systems with temporarily filled reservoirs, with a phased construction of waterworks on side tributaries, including secondary ones. Using the computer programs developed by the authors, the operating modes of the hydroelectric system were simulated for a possible variant of placing their sections on the lateral tributary of the river: in the lower reaches- a traditional hydro system with an earth dam and a concrete spillway, including bottom holes and a surface spillway; upstream- an additional hydro system with a filtering dam made of gabion masonry, into which the missing accumulating volume is redistributed. The calculation of the social effect resulting from the considered method of protection by assessing the reduction of economic damage for settlements located in the downstream of the main flood control hydroelectric complex with participation in the cutoff of the flood peak of an additional temporarily filled reservoir located upstream of the river is performed.
Early diagnostics of productivity and longevity of alfalfa selective samples
Authors: Bekuzarova S A , Lushchenko G V , Gasiev V I 
Published: June 2021

Abstract
The paper provides signs of productivity and longevity at the stage of seedlings, which accelerates selection in the breeding process for important indicators. Correlations between the shape of the root system and longevity, leaf area and productivity have been determined Key words: root system, morphology, productivity, varietal differences.
Study of the physicochemical properties of the biomedical composite material “Ti-Nb-Ta-Zr with a surface polymer layer”
Authors: Nasakina E O , Sevostyanova T M , Alexandrova A G , Kaplan M A , Kolmakova A A , Sudarchikova M A , Sergiyenko K V , Kuznetsova O G , Novikova D A , Shatova L A , Baikin A S 
Published: June 2021

Abstract
A comprehensive study of the physicochemical properties of the created biomedical composite material “Ti-Nb-Ta-Zr with a surface polymer layer” was carried out. The polymer film does not in any way affect the radiopacity of the base material. All materials obtained are radiopaque. X-ray diffraction analysis of polyglycolide lactide (PGLA) samples with molecular weights of 45, 90, 180 kDa showed that the polymers have a completely amorphous structure. On samples with a 40-μm-thick PLA-based coating bare-metal zones are observed, which substantiate anode effects in the potential range of more than 1000 mV.