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Impact of drilling waste pollution on land cover in a high subarctic forest-tundra zone

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Pedosphere 2022年第3期32卷 414-425页

作者： Anatoly OPEKUNOV Marina OPEKUNOVA stepan KUKUSHKIN Sergey LISENKOV Institute of Earth Sciences St.Petersburg State UniversitySt.Petersburg 199178(Russia)

Global climate changes can lead to the destruction of the permafrost zone and contribute to the active transfer of pollutants to natural *** can be especially pronounced in the areas of oil and gas production in the *** study aimed to define the landscape components(i.e.,groundwater,soil water,soil,and indicator plant species)of chemical pollution with metals,oil hydrocarbons,and polycyclic aromatic hydrocarbons,from the discharge of drill *** at two sites in the forest-tundra zone of Western Siberia(Russia)were carried out within two years of *** migration was found in peaty-gley heavy loamy soils and iron-illuvial clayey podburs,but lateral migration of different pollutants did not exceed 200 ***,radial migration was practically absent owing to the high buffering capacity of the soil organic horizon and the upward flow of matter in the seasonal melt *** main indicators of drilling waste pollution were high concentrations of Sr,Ba,petroleum hydrocarbons,and Cl^(-)*** the waste disposal sites,the concentration of Ba and Sr in the soil water were 1150 and 1410μg L^(-1),respectively;in groundwater,they reached 721 and 2360μg L^(-1),*** the soil,Ba and Sr accumulated in the peaty horizon(798 and 706 mg kg^(-1),respectively).The concentration of Cl^(-)ions in the soil water at the site of waste discharge was 1912 mg L^(-1),and at a distance of 200 m,it decreased to 77.4 mg L^(-1).The Cl^(-)concentration in the groundwater was lower,and at a distance of 200 m,it was 38.9 mg L^(-1).The highest concentration of petroleum hydrocarbons in the surface layer was found in the peaty-gley soils(up to 2400 mg kg^(-1)).In glandular-illuvial podburs,it was 420 mg kg^(-1).In horizons BH and BC,it was close to the background values(27 and 33 mg kg^(-1),respectively).Alkalinization of soils and water under the influence of drill cuttings led to the death of oligotrophic and acidophilic vegetation at a distanc

关键词： metal petroleum hydrocarbons plant indicator species pollutant migration in soil polycyclic aromatic hydrocarbon

High performance Wannier interpolation of Berry curvature and related quantities with WannierBerri code

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npj Computational Materials 2021年第1期7卷 293-301页

作者： stepan S.Tsirkin Department of Physics University of ZurichWinterthurerstrasse 190Zurich CH-8057Switzerland

Wannier interpolation is a powerful tool for performing Brillouin zone integrals over dense grids of k points,which are essential to evaluate such quantities as the intrinsic anomalous Hall conductivity or Boltzmann transport ***,more complex physical problems and materials create harder numerical challenges,and computations with the existing codes become very expensive,which often prevents reaching the desired *** this article,I present a series of methods that boost the speed of Wannier interpolation by several orders of *** include a combination of fast and slow Fourier transforms,explicit use of symmetries,and recursive adaptive grid refinement among *** proposed methodology has been implemented in the python code WannierBerri,which also aims to serve as a convenient platform for the future development of interpolation schemes for other phenomena.

关键词： interpolation quantities Wannier

Strain-Rate Dependency of a Unidirectional Filament Wound Composite under Compression

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2149-2161页

作者： stepan Konev Victor A.Eremeyev Hamid M.Sedighi Leonid Igumnov Anatoly Bragov Aleksandr Konstantinov Ayaulym Kuanyshova Ivan Sergeichev Skolkovo Institute of Science and Technologies Center for Materials TechnologiesMoscowRussia National Research Lobachevsky State University of Nizhny Novgorod Nizhny NovgorodRussia Dipartimento di Ingegneria Civile Ambientale e Architettura(DICAAR)Universitàdegli Studi di CagliariCagliari(CA)Italy Mechanical Engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvazIran Drilling Center of Excellence and Research Center Shahid Chamran University of AhvazAhvazIran

This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under *** test samples were manufactured through the filament winding of flat *** establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure Bar method,and standard static *** samples were loaded both along and perpendicular to the direction of the reinforcing *** applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during *** a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were *** on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are *** is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under *** increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,*** loading resulted in a strength and elastic modulus increase by 58%and 50%,*** average strength along the fibers at the largest studied strain rate was about *** obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.

关键词： High strain rate composites filament winding dynamic strength Split Hopkinson Pressure Bar compression

Resolving impact volatilization and condensation from target rock mixing and hydrothermal overprinting within the Chicxulub impact structure

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Geoscience Frontiers 2022年第5期13卷 16-31页

作者： Thomas Déhais stepan M.Chernonozhkin Pim Kaskes Sietze J.de Graaff Vinciane Debaille Frank Vanhaecke Philippe Claeys Steven Goderis Analytical Environmental and Geo-ChemistryVrije Universiteit BrusselBrusselsBelgium Laboratoire G-Time UniversitécLibre de BruxellesBrusselsBelgium Department of Chemistry Atomic&Mass SpectrometryGhent UniversityGhentBelgium

This work presents isotopic data for the non-traditional isotope systems Fe,Cu,and Zn on a set of Chicxulub impactites and target lithologies with the aim of better documenting the dynamic processes taking place during hypervelocity impact events,as well as those affecting impact structures during the post-impact *** focus lies on material from the recent IODP-ICDP Expedition 364 Hole M0077A drill core obtained from the offshore Chicxulub peak *** ejecta blanket samples from the UNAM 5 and 7 cores were used to compare the crater lithologies with those outside of the impact *** datasets of bulk Fe,Cu,and Zn isotope ratios are coupled with petrographic observations and bulk major and trace element compositions to disentangle equilibrium isotope fractionation effects from kinetic *** observed Fe and Cu isotopic signatures,with δ^(56/54)Fe ranging from0.95‰to 0.58‰and δ^(65/63)Cu from0.73‰to 0.14‰,mostly reflect felsic,mafic,and carbonate target lithology mixing and secondary sulfide mineral formation,the latter associated to the extensive and long-lived(>105 years)hydrothermal system within Chicxulub *** the other hand,the stable Zn isotope ratios provide evidence for volatility-governed isotopic *** heavier Zn isotopic compositions observed for the uppermost part of the impactite sequence and a metamorphic clast(δ^(66/64)Zn of up to 0.80‰and 0.87‰,respectively)relative to most basement lithologies and impact melt rock units indicate partial vaporization of Zn,comparable to what has been observed for Cretaceous-Paleogene boundary layer sediments around the world,as well as for tektites from various strewn *** contrast to previous work,our data indicate that an isotopically light Zn reservoir(δ^(66/64)Zn down to0.49‰),of which the existence has previously been suggested based on mass balance considerations,may reside within the upper impact melt rock(UIM)*** observation is restricted to a few UIM sampl

关键词： Chicxulub impact structure Non-traditional stable isotopes Impact volatilization Impact condensation Hydrothermal alteration Target lithology mixing

HOMOCLINIC SOLUTIONS OF NONLINEAR LAPLACIAN DIFFERENCE EQUATIONS WITHOUT AMBROSETTI-RABINOWITZ CONDITION

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Acta Mathematica Scientia 2021年第3期41卷 712-718页

作者： Antonella NASTASI stepan TERSIAN Calogero VETRO University of Palermo Department of Mathematics and Computer ScienceVia Archirafi 3490123PalermoItaly Institute of Mathematics and Informatics Bulgarian Academy of Sciences1113 SofiaBulgaria

The aim of this paper is to establish the existence of at least two non-zero homoclinic solutions for a nonlinear Laplacian difference equation without using AmbrosettiRabinowitz type-conditions. The main tools are mo... 详细信息

关键词： Difference equations homoclinic solutions non-zero solutions (p,q)-Laplacian operator

ON THE FOURIER-VILENKIN COEFFICIENTS

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Acta Mathematica Scientia 2017年第2期37卷 293-300页

作者： Martin G.GRIGORyan stepan sarg.yan Chair of Higher Mathematics Faculty of Physics Yerevan State University

In this article, we prove the following statement that is true for both unbounded and bounded Vilenkin systems： for any ε∈ （0, 1）, there exists a measurable set E C [0, 1） of measure bigger than 1 - s such that for any function f ∈ LI[0, 1）, it is possible to find a function g ∈ L^1 [0, 1） coinciding with f on E and the absolute values of non zero Fourier coefficients of g with respect to the Vilenkin system are monotonically decreasing.

关键词： Vilenkin system expansions Fourier coefficients

Thermal radiation and natural convection in a large-scale enclosure heated from below:Building application

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Building Simulation 2021年第3期14卷 681-691页

作者： stepan A.Mikhailenko Igor V.Miroshnichenko Mikhail A.Sheremet Laboratory on Convective Heat and Mass Transfer Tomsk State University634050 TomskRussia Regional Scientific and Educational Mathematical Centre Tomsk State University634050 TomskRussia

A computational research of radiative-convective energy transport in large-scale enclosure with a heat-generating heater under normal room conditions has been *** heater(underfloor heating system)is located at the bottom of the *** the Boussinesq assumption,the control equations have been solved contemporaneously to receive both the velocity fields and temperature *** generate the systems of linear equations using vorticity and stream function,the finite difference technique has been *** developed convective-radiative model has been validated through a comparison with several *** influence of heater size and location,internal surfaces emissivity from 0 to 1,Ostrogradsky number for a wide range from 0 to 5 on Nusselt numbers and both stream function and temperature distributions has been *** results demonstrate that the influence of the thermal radiation on total heat transfer increases with surface emissivity of walls and heater surfaces.

关键词： indoor environment natural convection thermal radiation large-scale cabinet local heater finite difference method

Accuracy estimation of site coordinates derived from GNSS-observations by non-classical error theory of measurements

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Geodesy and Geodynamics 2021年第5期12卷 347-355页

作者： Petro Dvulit stepan Savchuk Iryna Sosonka Department of Higher Geodesy and Astronomy Lviv Polytechnic National UniversityLvivUkraine Institute of Navigation Military University of AviationDeblinPoland

The velocities of tectonic plates derived from GNSS time series are regularly used as input data for geophysical models. However, as shown by numerous researches, the coordinates time series contain residual errors of a systematic nature, which can significantly affect the reliability of the obtained velocity estimates. This research shows that using non-classical error theory of measurement(NETM)for processing GNSS time series allows detecting the presence of weak, not removed from GNSS processing, sources of systematic errors. Based on the coordinate time series of selected permanent GNSS stations in Europe, we checked the empirical distributions of errors by the NETM on G. Jeffries’ recommendations and on the principles of the theory of hypothesis tests according to Pearson’s criterion. It is established that the obtained coordinates time series of GNSS-stations only partially confirm the hypothesis of their conformity to the normal Gaussian distribution law, and this may be the main reason for their unrepresentative classification. In the future, it is necessary to identify and take into account the causes of residual errors that distort the real distribution of the results of the GNSS time series.

关键词： GNSS data Processing GNSS time Series Discontinuities in time series Non-classical error theory of measurements Noise analysis

Optimization of the Cooling System of Electric Vehicle Batteries

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Fluid Dynamics & Materials Processing 2022年第3期18卷 835-850页

作者： A.Heri Iswanto Iwan Harsono Alim Al Ayub Ahmed Sergushina Elena Sergeevna stepan Krasnikov Rustem Zalilov John William Grimaldo Guerrero Liliya N.Latipova Safa Kareem Hachim Public Health Department Faculty of Health ScienceUniversity of Pembangunan Nasional Veteran JakartaJakarta16426Indonesia Universitas Mataram West Nusa Tenggara83116Indonesia School of Accounting Jiujiang UniversityJiujiang330300China National Research Ogarev Mordovia State University Saransk430005Russia Russian Technological University Moscow119454Russian Nosov Magnitogorsk State Technical University Magnitogorsk455000Russian Departamento de Energía Universidad de la CostaBarranquilla080002Colombia Kazan Federal University Kazan628400Russia College of Technical Engineering The Islamic UniversityNajaf54001Iraq

The most important components of electrical vehicles are the battery and the related cooling *** subsystems play a major role in determining the overall electric vehicle *** this study,a novel cooling system with fluid in the battery cell is proposed,by which the energy storage system can be optimized through control of the temperature of the batteries.A sensitivity analysis is conducted considering the maximum temperature,the heat rate,the coolant temperature,and the geometry of the *** numerical simulations show that the parameters for the trapezoidal compartment have an impact on the thermal performance of *** optimal geometry is proposed *** is concluded that for high values of Reynolds number for which the flow becomes turbulent,a decrease in the battery temperature can be obtained thereby avoiding thermal stresses.

关键词： Thermal flow batteries geometry cavity cooling system