bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrostatic compression as the way of property improvement of crumpled graphene: atomistic simulation
Authors: Krylova K. A. , Safina L. R. 
Published: January 2020

Abstract
In the present work, crumpled graphene is considered under hydrostatic tension by molecular dynamics simulation. Here hydrostatic compression is used in two variants: to obtain composite from crumpled graphene combined with Ni nanoparticles and to serve hydrogen inside crumpled graphene. Pressure-strain curves and structural transformations during hydrostatic compression in both cases are discussed. It is found, that hydrostatic compression at high temperatures can be very effective for Ni-graphene composite formation. The possibility of application of compressive strain to make crumpled graphene better media for hydrogen storage is discussed. It is observed that at 77 K and 300 K compression results in the considerable increase of hydrogen sorption capacity.
Total fission energy depending on VVER-1000 fuel burnup
Authors: Bahdanovich R , Gerasimov A , Tikhomirov G 
Published: January 2020

Abstract
To calculate the energy deposition in a nuclear reactor’s core, it is necessary to calculate the value of the energy released per one fission act. Simplified methods for calculating the total fission energy are still used in many computer codes. They do not take into detailed account some of the physical phenomena occurring in nuclear fission and their time dependence. In this work, we used a calculation method that takes into account these physical features in order to obtain the dependence of the total fission energy and its components on the fuel burnup of VVER-1000. The calculation for the model of 16ZSH type fuel assembly using the methodology of the Fisencor.pl program (based on the MCU-PTR code) demonstrated that total fission energy increases with the fuel burnup. During the interval between refuelling, total fission energy increases by 3% from 199.7 to 206.4 MeV per one fission. Application of the proposed method for calculating the total fission energy will allow to enhance the precision of nuclear fuel isotopic composition calculations.
Analysis of the methods for group constants generation for calculation of a large SFR core using Serpent 2 and CriMR codes
Authors: Akpuluma D A , Smirnov A D , Pugachev P A , Tikhomirov G V , Gerasimov A S 
Published: January 2020

Abstract
This work aimed at generating homogenized group constants using the Serpent code and then using the CriMR diffusion code to model the large SFR OECD 3600 MWth MOX core. The results were compared with a full core reference Monte Carlo solution by Serpent. Reactivity feedback parameters were also considered. Generating the group constants from separate fuel assemblies allows for simultaneously carrying out calculations and then using the results as input in diffusion codes rather than waiting so long for a 3D full core Monte Carlo calculation to be completed. From the results of the integral parameters we see a close agreement in the calculation codes. The differences can be attributed to the errors that could arise from generating the constants from individual sub-assemblies. The differences in the underlying physics and approximations used in development of the codes could also be a factor. Another way the errors could be reduced is by checking to see that the sub-assembly configurations used in the non-multiplying zones are as close as possible to the real layout in a full 3D core.
Study of the trigger on nucleus-nucleus interactions for the BM@N experiment using a Geant4 + QGSM software package
Authors: Lashmanov N A , Sedykh S A , Yurevich V I 
Published: January 2020

Abstract
Monte-Carlo simulation was used to study the background conditions which affect the performance of the trigger system of the BM@N experiment. A GEANT4 + QGSM software package was used for the simulation. The influence of the background from δ-electrons was estimated and measures to minimize this background were evaluated. Addition of lead shielding and a small change in the geometry of the target zone allow to reduce the background. The efficiency of the modified trigger system was calculated for Au+Au collisions as a function of the impact parameter. The efficiency is 100% for central and semi-central collisions.
GEANT4 simulation of energy resolution of the SPACAL electromagnetic calorimeter
Authors: Shmanin E 
Published: January 2020

Abstract
Geant4 based simulation study of energy resolution is performed for Spaghetti electromagnetic calorimeter module (SPACAL). Several configurations of SPACAL module, with different fiber pitch and scintillation material, were simulated. For each configuration, the energy and angular dependencies of energy resolution were determined. The sampling fraction for electromagnetic showers for the selected SPACAL configuration was also determined
Pressure drop in valve for different open flow areas
Authors: Laouar Soufiane , Sakib Md Nazmus , Muqit Al Sazid , Navasardyan Manuk V. , Kutsenko Kirill V. 
Published: January 2020

Abstract
In any piping system different types of regulating components (valves) are used. To determine the pressure drop of the liquid in these components, it is necessary to know the exact values of the local loss coefficients, which depend on their design and manufacturer. The calculations of local loss coefficients of the valves are usually carried out according to engineering methods using design handbooks. However, the large design diversity of the valves does not allow an accurate assessment of the local loss coefficient for a particular product (using handbooks). There are two ways to solve this problem. The first way is experimental determination; the second is calculation using CFD modelling. This article presents the results of CFD simulation of the pressure drop of liquid through valves and a comparison with experimental data obtained from the thermal hydraulic test bench.
Development of a method for determining corrosion damage of fuel element claddings of a nuclear power unit by using acoustic resonance method in a hot chamber environment
Authors: Rodko I I , Moshev A A , Bozhko Yu V , Yudin I A , Tokarev A N , Biryukov A P , Chernykh P O , Tolstov M S 
Published: January 2020

Abstract
As part of the strategic research program of state corporation Rosatom, carried out by the Technological Platform “Closed Nuclear Fuel Cycle with Fast Neutron Reactors”, a research to equip protective cells with original equipment, including ultrasonic flaw detectors for primary post-reactor non-destructive research of the properties of critical materials of fast neutron reactors, is being performed. In this paper, we present a method developed for determining corrosion damage of fuel claddings by the acoustic resonance method in hot chamber conditions, and a description of the experimental installation.
Determination of types and degree of corrosion damage of fuel cladding by informative ranges of divergences of their natural oscillation frequencies
Authors: Moshev A A , Rodko I I , Berestov A V , Yudin I A , Tokarev A N , Biryukov A P , Ocheretko V E , Gavrilyuk M Yu 
Published: January 2020

Abstract
The urgency of the work consists in using a new approach to the definition of informative frequencies for the identification of corrosion damage. The aim of the work is to determine the discrepancies between the resonance frequencies of the oscillations of the fuel casing segments of the factory geometry and with various types of corrosion damage obtained by modelling defects in the casings of fuel casing segments. As a result of the analysis, informative ranges of ordinal numbers were revealed, which allow to determine the following corrosion damages: thinning from the outer and inner sides of the fuel casing, pitting corrosion, fretting corrosion.
The synchronous movement of mechanisms taking into account forces of the different nature
Authors: Misyurin S Yu , Kreinin G V , Nelubin A P , Nosova N Yu 
Published: January 2020

Abstract
In the work the method of transition to dimensionless parameters is presented on the example of movement by two synchronously working piston hydraulic engines of a heavy object with use of the theory of similarity and analogousness. Advantage of such approach is shown in limit simplification of dimensionless model, its universality and efficiency of search of an optimal solution in the choice of parameters of the real device.
Methods of dimension and the theory of similarity are successfully applied in a research of dynamic systems of various classes. The problems arising at the same time are connected generally with the choice of a rational combination of the main units of measure of physical quantities, with transition to dimensionless models and with formation basic criterion of similarity. The specified problems are solved by the researcher, as a rule, on the basis of own intuition and experience. The systematized approaches to the solution of similar problems based on a method of the theory of analogousness are meanwhile known.
E-beam longitudinal pumped semiconductor laser based on ZnCdS/ZnSSe type-II multi quantum well structure
Authors: Butaev M R , Kozlovsky V I , Sannikov D A , Skasyrsky Y K 
Published: January 2020

AbstractA ZnCdS/ZnSSe multi quantum well structure was grown by metal-organic vapor phase epitaxy on GaAs substrate. The structure is consisted of the 45 ZnCdS layers of 5 nm in thickness separated by the 100 nm thin ZnSSe barrier layers and was the type-II heterostructure. A microresonator was produced from this structure for scanning electron beam longitudinal pumping. Lasing with output power up to 2W at 478 nm was achieved at room temperature.
Enhancement of the photoluminescence of semiconductor nanocrystals in transfer-printed microcavities based on freestanding porous silicon photonic crystals
Authors: Kryukova I S , Dovzhenko D S , Rakovich Yu P , Nabiev I R 
Published: January 2020

Abstract
Today, lots of research address the phenomenon of interaction between light and matter. In particular, it is of a special interest to investigate light–matter interaction in one-dimensional resonators based on porous materials. In this case, one can embed emitting semiconductor particles into the porous resonator, where the excitons of these particles couple to the resonator eigenmode and luminescence intensity of the emitters is enhanced, allowing an increase in the sensitivity of optical sensors, detectors, and photonic diagnostic assays. A particular challenge is to place the emitters directly in the antinode region of the resonator eigenmode in order to maximize the coupling strength, which is sometimes a problem due to the spatial distribution of emitters away from the eigenmode localization region. Here, we have shown that the transfer-printing technique can be used to obtain structures based on freestanding porous silicon photonic crystals capable of precisely controlling the emitter spatial distribution about the eigenmode localization region. This, as well as the porosity of these structures and high adsorption capacity of porous silicon, allows the light–matter interaction in these hybrid structures to be used in sensing applications. We have shown that the transfer-printing method does not worsen the optical properties of the microcavities compared to the conventional electrochemical etching of the whole microcavity at a time. Furthermore, we have observed slightly better coupling of the exciton of the emitter to the eigenmode of the transfer-printed microcavity in the weak coupling regime.
Acoustical monitoring of laser-matter interaction using nanosecond radiation pulses with periodically modulated intensity
Authors: Zubko A E , Samokhin A A , Shashkov E V , Vorob’ev N S 
Published: January 2020

Abstract
Nanosecond laser ablation of metal target under the action of radiation pulses with periodically modulated intensity is investigated. Generated pressure pulses are detected by piezo-transducer (lithium niobate) on the back target side. Such approach permits to measure simultaneously recoil pressure behavior and calculate the irradiated surface displacement during laser action by comparison modulated parts of laser and acoustic signals. Nanosecond laser pulses contain 10–15 short peaks of 60 ps duration (1.08 μm wavelength) which provide fluence values up to 30 J cm−2 in the pulse. Plasma light emission is also registered with the help of photodiode. At the considered fluences surface displacement during the pulse turns out to be considerably smaller than theoretical estimation for free vacuum vaporization and measured experimental displacement which follows from the arrival time delay of another pressure signals generated with subsequent laser pulse directed to the same spot. Such behavior can be evidence that crater formation in the considered irradiation regime occurs after the pulse end.
Influence of ZnGeP2 crystal temperature on broadband cascaded frequency conversion (numerical study)
Authors: Ionin A A , Kinyaevskiy I O , Sagitova A M 
Published: January 2020

Abstract
Broadband three-stage frequency conversion of multiline CO laser radiation in a single sample of ZnGeP2 crystal was numerically studied at various crystal temperatures. Decrease of the ZnGeP2 crystal temperature resulted in enhancement of efficiency for each frequency conversion stage due to phase-matching shifting. The third stage efficiency at liquid-nitrogen crystal temperature was 1.7-fold higher as compared to one at the room temperature. Also, the crystal temperature decrease resulted in spectral broadening of frequency converted radiation.
The oscillations of charged particle beam in crossed magnetic fields
Authors: Bulygin A.M. 
Published: January 2020

Abstract
In the present paper we are going to study the decrease of the velocity and density oscillations of the beam in the non-relativistic charged particle beams in the chosen configuration of the crossed field. This paper examines using a hydrodynamic approach and the Maxwell’s processes inside the cold beam. Results show that in the framework of the present model one can obtain physical conditions when it is possible to observe the cooling effect for the charged particle beam.
Mechanisms of formation of the structure of welded joints, performed by friction stir welding
Authors: Rzaev R A , Alykova O M , Smirnov V V , Kanavin A P , Zavestovskaya I N 
Published: January 2020

Abstract
The analysis of welded joints of structural materials is carried out. As a result of this, in addition to the traditionally formed zone of thermal influence (HAZ), a zone of thermal deformation influence is formed in the near-seam zone, located between the welded nugget and the HAZ. The welded nugget joints in FSW is formed in the regime of structural superplasticity (SP). The structure of the welded nugget has a sheared band structure in the form of an "onion pattern" consisting of a large number of lamellas forming shear bands under the influence of a movable welding tool. The attainment of the superplastic state (SPS) during the formation of the welded nugget is ensured by the stepwise flow of various mechanisms of plastic deformation in the regime of simple, collective, anomalous dynamic recrystallization, prepared by dynamic return processes, polygonization with transition to postdynamic recrystallization by the mechanisms of Bailey- Hirsch, Kahn-Burgers-Taylor. For the group of metals and alloys with polyformism (high-alloy steels of different structural classes, Ti- alloys), SPS is supported additionally by recrystallization by twinning (copper, austenitic steel and other structural classes, Ti and its alloys) and as a result of phase transformations of alpha-gamma or alpha-beta phases).
The Percolation Model of the Structure of the Polymer Nanocomposite, Containing the Carbon Nanotubes, with the Orient Factor Availability
Authors: Bokov K A , Buzmakova M M 
Published: January 2020

Abstract
The percolation lattice model of the structure of the polymer thin film, containing the carbon nanotubes, with the orient factor availability is proposed in this paper. From the model: the polymer matrix is the square lattice with linear size L; the carbon nanotubes are k-meres (k consecutive occupied nodes of the lattice); the interphase regions are nodes of the bond between k-meres. Also where is the orient factor for the carbon nanotubes in the form of the electric current, flowing in one direct during the structure formation of the nanocomposite. For the modeling the periodic boundary conditions are used. For the model the percolation threshold values are obtained for two cases: for the uniform distribution of the k-meres on the square lattice and for the unidirectional k-meres on the square lattice. According to the made natural experiments [1], the linear orientation in the field of electric current force is possible at the small concentration of nanotubes. In the model it is supposed, during the consolidation all nanotubes manage to be developed and get the identical direction.
Thermo-elastic stress in high-power laser bars
Authors: Bezotosnyi V V , Gordeev V P , Oleshchenko V A 
Published: January 2020

Abstract
This article presents the results of three-dimensional modeling of thermo-elastic stresses arising during the operation of a powerful laser diode bars mounted on a CuW thermal compensator using AuSn soldering alloy in a wide range of thermal loads up to extreme values. Calculated distributions of thermo-elastic stresses at the output and highly reflective mirror of the laser bar is compared. An interpretation of the results obtained, in particular, higher values of thermo-elastic stresses on a less hot highly reflective mirror, in comparison with a hotter output mirror, is proposed.
The influence of chemical structure of phosphonic acids labeled with gallium-68 on their pharmacokinetic properties in animals
Authors: Petriev V M , Tishchenko V K , Mikhailovskaya A A , Stepchenkova E D , Kuzenkova K A , Postnov A A , Zavestovskaya I N 
Published: January 2020

Abstract

68 Ga-labeled phosphonates are of great interest due to their possibility to serve promising agents in nuclear medicine for bone tissue PET imaging. It is known that multidentate aminophosphonate ligands could form much stable chelates with different radiometals as compared to diphosphonates. In this work we studied the pharmacokinetic properties of 68Ga-labeled complexes with two, four and five phosphonate groups (68Ga-HEDP, 68Ga-EDTMP, and 68Ga-DTPMP, respectively) in normal Wistar rats after intravenous administration. It was shown that the structure of phosphonates had a great influence on the biodistribution of 68Ga-HEDP, 68Ga-EDTMP, and 68Ga-DTPMP. Complexes with higher number of aminomethylenephosphonate groups (68Ga-EDTMP and 68Ga-DTPMP) had higher bone uptake than diphosphonate 68Ga-HEDP. In blood 68Ga-HEDP had lower activity than 68Ga-EDTMP and 68Ga-DTPMP, indicating poor stability of diphosphonate-based complex. In other soft organs and tissues 68Ga-EDTMP and 68Ga-DTPMP uptake was slightly lower as compared with 68Ga-HEDP. In conclusion, 68Ga-EDTMP and 68Ga-DTPMP have the potential to be suitable radiotracers for bone tissue PET imaging.
Preliminary biological evaluation of 99mTc-glucosamine as a potential radiotracer for tumor imaging
Authors: Tishchenko V K , Petriev V M , Mikhailovskaya A.A. , Smoryzanova O.A. , Ivanov S A , Kaprin A D 
Published: January 2020

Abstract
The development of novel specific radiolabeled probes as targeted imaging agents for a more accurate detection of cancer has gained considerable interest. Glucose analogue 18F-FDG is used worldwide for imaging of several cancer types. New glucose analogs radiolabeled with 99mTc could be a less-expensive and more accessible alternative for diagnosis using SPECT imaging. The complex of glucosamine and 99mTc were prepared, and its biodistribution was evaluated in solid Ehrlich carcinoma bearing mice. 99mTc-glucosamine was synthesized and radiolabeled with 99mTc with high yield and stability. Biodistribution studies showed that tumor uptake of 99mTc-glucosamine increased from 0.44±0.06 %ID/g at 5 min postinjection (p.i.) to 0.54±0.06 %ID/g and 0.64±0.07 %ID/g at 1 h and 3 h p.i., respectively. The tumor/blood and tumor/muscle ratios also increased with time and reached 1.02±0.12 and 1.88±0.20 at 3 h p.i. 99mTc-glucosamine was rapidly removed from blood through the urinary system, so high amount of activity accumulated in kidneys. High uptake of 99mTc-glucosamine was also observed in two high-energy-dependent organs, heart and liver. In other organs such as lungs, spleen, stomach, small intestine and brain high uptake of 99mTc-glucosamine was only at 5 min after intravenous administration, but later the most part of activity was removed. In conclusion, we suggested that 99mTc-glucosamine would be a promising candidate for cancer SPECT imaging.
Personal empathy and social-psychological climate as factors of learning satisfaction in linguistic university students
Authors: Velichkovskaya Sofia , Grebennikova Tatiana 
Published: January 2020

Abstract
The article contemplates on the results of empirical research on personal empathy and social-psychological climate as factors of learning satisfaction in linguistic university students. Data acquired allowed to broaden the concept of social-psychological climate shaping in a study group. They also contributed to raising awareness of empathy skill level in students and the specific features of learning satisfaction in students of different specialties.
Structural-dynamic models of aspirin isomers in the condensed state
Authors: Elkin M D , Smirnov V V , Alykova O M , Alykova A F , Zavestovskaya I N 
Published: January 2020

Abstract
Structural-dynamic models of aspirin are proposed on the basis of non-empirical quantum calculations of geometrical and electronic structure. In this work, the parameters of the adiabatic potential are determined, and the interpretation of the vibrational states of the compound under study is proposed. Structural-dynamic models of its isomers are constructed, the signs of their spectral identification are revealed. The conformational structure of the molecules of the substance under study was analyzed. The choice of the method and the basis for calculating the fundamental vibration frequencies and band intensities in the IR and Raman spectra are substantiated. A method for estimating anharmonic vibrations using cubic and flat force constants is described. The article presents the results of a numerical experiment; the geometrical parameters of the molecules, such as the lengths of the valence bonds and the magnitudes of the angles between them, are determined. The frequencies of the vibrational states and the magnitudes of their integrated intensities are obtained. The interpretation of isomer vibrations is given and compared with the available experimental data. General regularities in the behavior of spectral bands of different isomers are shown. Frequencies that can be used to identify the isomer from the vibrational spectra of molecules are proposed. The calculation was carried out by the DFT/B3LYP density functional quantum method. It is shown that this method can be used to model the geometrical parameters of molecules and the electronic structure of various substituted benzoic acid. It allows to construct structural-dynamic models of the specified class of compounds on the basis of numerical calculations.