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Frontiers of Structural and Civil Engineering 2019年第1期13卷 190-200页

作者： Eric N.LANDIS Roman KRAVCHUK dmitry LOSHKOV Department of Civil &Environmental Engineering University of MaineOronoME 04469USA

Split-cylinder fracture of fiber-reinforced ultra-high-performance concrete (UHPC)was examined using two complementary techniques:X-ray computed tomography (CT)and acoustic emission (AE).Fifty-mm-diameter specimens of two different fiber types were scanned both before and after load *** the CT images,fiber orientation was evaluated to establish optimum and pessimum specimen orientations,at which fibers would have maximum and minimum effect,*** expected,fiber orientation affected both the peak load and the toughness of the specimen,with the optimum toughness being between 20% and 30%higher than the *** AE energy was also affected *** CT scans of the specimens were used to measure internal damage. Damage was quantified in terms of internal energy dissipation due to both matrix cracking and fiber pullout by using calibration measurements for *** results showed that fiber pullout was the dominant energy dissipation mechanism;however,the sum of the internal energy dissipation measured amounted to only 60% of the total energy dissipated by the specimens as measured by the net work of *** is postulated that localized compaction of the UHPC matrix as well as internal friction between fractured fragments makes up the balance of internal energy dissipation.

关键词： ultra-high-performance concrete concrete fracture X-ray computed tomography acoustic emission

Ecological Niche Modelling Reveals the Peculiarities of Ecological Disjunction Between Two Sympatric Racerunners in Kazakhstan:Eremias lineolata(Nikolsky,1897)and Eremias scripta(Strauch,1867)

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Asian Herpetological Research 2023年第2期14卷 123-137页

作者： Marina A.CHIRIKOVA dmitry V.MALAKHOV Institute of Zoology Committee of Scientific Ministry of Science and Higher EducationAl-Farabi 93 AkademgorodokAlmaty 050060Kazakhstan

The ecological-niche models for two sympatric species,Eremias lineolata(Nikolsky,1897)and Eremias scripta(Strauch,1867),reveal evidence of spatial and temporal disjunction in the actual niches of both *** lineolata demonstrates a wide range of adaptations and,at the same time,has a greater need for winter precipitation and minimal temperature than *** explanations for the thermal diversity of both species are *** variables(monthly temperatures,monthly solar radiation,etc.)are traditionally important for ectotherm ***,as many as half of the key variables in both species are related to different aspects of environmental water balance(precipitation,air humidity,vapor pressure).There are several ways in which moisture may impact the lizard’s life *** humidity is related to soil temperature and may be important during winter *** summer,soil humidity may support successful *** during the warm months is a key factor in maintaining the moisture content of the *** winter,snow cover provides a better thermal balance of the soil’s top layers where winter shelters are *** niche modeling(ENM)is an interdisciplinary approach combining the geographical,climatic,ecological,and biological aspects of the wellbeing of *** interdisciplinary approach lifts biological studies onto a new,integrative level,providing a comprehensive view on species biology and answering the questions that might not be answered if the traditional methods for studying animals were used alone.

关键词： ecology Kazakhstan niche modelling racerunners species distribution

Unsteady bio-fluid dynamics in flying and swimming

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Acta Mechanica Sinica 2017年第4期33卷 663-684页

作者： Hao Liu dmitry Kolomenskiy Toshiyuki Nakata Gen Li Graduate School of Engineering Chiba University 1-33Yayoi-cho Inage-ku Chiba Japan Shanghai-Jiao Tong University and Chiba UniversityInternational Cooperative Research Centre (SJTU-CU ICRC) Shanghai 200240 China

Flying and swimming in nature present sophisticated and exciting ventures in biomimetics, which seeks sustainable solutions and solves practical problems by emulating nature＇s time-tested patterns, functions, and strategies. Bio-fluids in insect and bird flight, as well as in fish swimming are highly dynamic and unsteady; however, they have been studied mostly with a focus on the phenomena associated with a body or wings moving in a steady flow. Characterized by unsteady wing flapping and body undulation, fluid-structure interactions, flexible wings and bodies, turbulent environments, and complex maneuver, bio-fluid dynamics normally have challenges associated with low Reynolds number regime and high unsteadiness in modeling and analysis of flow physics. In this article, we review and highlight recent advances in unsteady bio-fluid dynamics in terms of leading-edge vortices, passive mechanisms in flexible wings and hinges, flapping flight in unsteady environments, and micro-structured aerodynamics in flapping flight, as well as undulatory swimming, flapping-fin hydrodynamics, body–fin interac-tion, C-start and maneuvering, swimming in turbulence,collective swimming, and micro-structured hydrodynamics in swimming. We further give a perspective outlook on future challenges and tasks of several key issues of the field.

关键词： swimming wings unsteady turbulence hydrodynamics turbulent body kinematics vortex street

Transformation of the TiNi Alloy Microstructure and the Mechanical Properties Caused by Repeated B2-B190' Martensitic Transformations

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Acta Metallurgica Sinica(English Letters) 2015年第10期28卷 1230-1237页

作者： Anna Churakova dmitry Gunderov Alexander Lukyanov Niklas Nollmann Institute of Molecule and Crystal Physics RAS Ufa State Aviation Technical University Institute of Materials Physics University of Münster

The influences of thermal cycling treatment in the temperature range of B2-B19 martensitic transformations（-150 to 150 °C） on the Ti Ni alloy structure and properties were studied. Different states named the initial coarse-grained（CG） state, the ultrafine-grained（UFG） state after ECAP（with a grain size of 200 nm）, the state after ECAP and cold upsetting by 30% were considered. The results show that the microhardness and the strength increase in all the three *** to the XRD analysis, a more significant increment in the dislocation density, resulting from thermal cycling, is observed in the UFG alloy than in the CG alloy.

关键词： Thermal cycling TiNi alloy Equal-channel angular pressing Martensitic transformation

Runaway electrons during subnanosecond breakdowns in high-pressure gases

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High Voltage 2016年第4期1卷 181-191页

作者： Victor F.Tarasenko Mikhail I.Lomaev dmitry V.Beloplotov dmitry A.Sorokin Institute of High Current Electronics Siberian Branch Russian Academy of Science2/3 Akademicheskii Ave.Tomsk 634055Russia

The parameters of runaway electrons produced in nanosecond high-voltage discharges in different gases(air,nitrogen,sulphur hexafluoride,krypton,argon,methane,neon,hydrogen,helium)at atmospheric and higher pressure were *** optical analysis was also performed to investigate the ionisation dynamics in diffuse discharges in nitrogen and nitrogen-containing *** breakdown of a point-to-plane gap by nanosecond(≃2 ns)high-voltage(≃200 kV)pulses of negative voltage polarity and gas pressure above 0.1 MPa,a supershort avalanche electron beam(SAEB)was detected by a collector behind the flat *** pressure>0.1 MPa of nitrogen and other gases it is shown that the maximum pressure for SAEB registration decreases with increasing the voltage pulse rise ***,to detect a SAEB at atmospheric and higher gas pressure,one should use voltage pulses with an amplitude of hundred kilovolts and rise time of∼1 ns and *** experimental research in the dynamics of optical radiation from the discharge plasma shows that the breakdown in which runaway electrons are produced develops as an ionisation wave.

关键词： wave. gases fluoride

Left atrial appendage aneurysm: A case report

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World Journal of Clinical Cases 2020年第19期8卷 4443-4449页

作者： dmitry Vladimirovich Belov Vladimir Ivanovich Moskalev dmitry Victorovich Garbuzenko Nikolay Olegovich Arefyev Department of Hospital Surgery South Ural State Medical UniversityChelyabinsk 454092Russia Department of Hospital Surgery Federal Center for Cardiovascular SurgeryChelyabinsk 454033Russia Department of Faculty Surgery South Ural State Medical UniversityChelyabinsk 454092Russia Department of Pathological Anatomy and Forensic Medicine South Ural State Medical UniversityChelyabinsk 454092Russia

BACKGROUND An aneurysm of the left atrial appendage is one of the rare but potentially hazardous heart *** risk of lethal complications grows with its *** date,about 150 cases of this defect have been described in the *** present a case of left atrial appendage aneurysm with the deformation of the mitral valve and the left main coronary and circumflex artery,which required mitral valve annuloplasty and bifurcation *** SUMMARY A 58-year-old man presented to our hospital complaining of shortness of breath,general weakness,dizziness during physical exertion,and *** on the results of echocardiography,an aneurysm of the left atrium was suspected.A free-breathing real-time cine magnetic resonance imaging with electrocardiograph synchronization confirmed the diagnosis of left atrial appendage *** patient underwent an aneurysmectomy via a median sternotomy with cardiopulmonary *** transesophageal echocardiography revealed relative mitral insufficiency that was corrected with an annuloplasty *** coronary angiogram showed impaired blood flow in the left main coronary and circumflex artery and 60%*** this reason,bifurcation stenting was *** patient had an uneventful postoperative clinical course and was discharged from the hospital on the 10th day in a satisfactory *** Left atrial appendage aneurysm is a rare and dangerous heart pathology that requires surgery to prevent related complications.

关键词： Atrial appendage Aneurysm Mitral valve insufficiency Coronary stenosis Catheter ablation Case report

Technological Properties and Application of Analcime-Bearing Rocks of the Timan Region

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地学前缘 2009年第S1期16卷 159-160页

作者： dmitry Shushkov Institute of Geology Komi SC UB of RAS

Analcime-bearing rocks from Carboniferous and Permian sediments occupy a vast area in the Timan (Komi Republic,Russian Federation)—about 150.000 km^*** are represented by siltstones and *** analcime-bearing rocks have the following mineral composition(%):clay minerals (50-70),quartz(10-30),analcime(1-30),feldspars (2-10),carbonates(2-5),and pyroclastic material.

关键词： analcime zeolites ion-exchange physicochemical properties adsorbtion concentration

Orbits of Real Semisimple Lie Groups on Real Loci of Complex Symmetric Spaces

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Acta Mathematica Sinica,English Series 2018年第3期34卷 439-453页

作者： Stéphanie CUPIT-FOUTOU dmitry A.TIMASHEV Ruhr-Universitat Bochum Fakultat fiir Mathematik D-44780 Bochum Germany Lomonosov Moscow State University Faculty of Mechanics and Mathematics Department of Higher Algebra 119991 Moscow Russia

Let G be a complex semisimple algebraic group and X be a complex symmetric homogeneous G-variety. Assume that both G, X as well as the G-action on X are defined over real *** G（R） acts on X（R） with finitely many orbits. We describe these orbits in combinatorial terms using Galois cohomology, thus providing a patch to a result of Borel and Ji.

关键词： Semisimple group symmetric space real point orbit Galois cohomology

Influence of field emission on microwave microdischarges

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High Voltage 2016年第1期1卷 57-59页

作者： dmitry Levko Laxminarayan L.Raja Department of Aerospace Engineering and Engineering Mechanics The University of Texas at AustinAustinTexas 78712USA

An instability in the stable operation of microdischarges sustained at microwave frequencies,is investigated by a self-consistent one-dimensional particle-in-cell Monte Carlo collisions *** instability is caused by the field electron emission from electrodes and is triggered by the high electric fields at the sheaths in a dense *** an operating frequency of 9 GHz,and electrode gap of 60μm,the field emission(FE)is not active at the breakdown ***,once a stable dense plasma is produced post-breakdown,a strong sheath results in an electrode electric fields that exceed the threshold for FE causing a runaway in the electron generation in the plasma.

关键词： microwave electrode field

Features of the long-term transformation of the Krasnodar reservoir,near the mouth of the Kuban River,Russia

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Journal of Geographical Sciences 2021年第12期31卷 1895-1904页

作者： POGORELOV Anatoly LAGUTA Andrey KISELEV Evgeny LIPILIN dmitry Kuban State University Krasnodar 350040Russia Aerogematica LLC Krasnodar 350063Russia Kuban State Agrarian University Named after I.T.Trubilin Krasnodar 350044Russia Tuapse Branch of the Russian State Hydrometeorological University Krasnodar RegionTuapse 352800Russia

The article considers the long-term(1941-2018)transformation of the Krasnodar valley reservoir,the largest in the North *** main functions of the Krasnodar reservoir are irrigation of rice systems and flood protection of land in the Krasnodar reservoir region and the Republic of *** to topographic maps,Landsat satellite images(1974-2018)and field observations(2016-2018),four stages of transformation of the floodplain reservoir are *** selected stages are characterized by both natural causes(the transformation of the filling deltas into the extended deltas,etc.)and man-made causes(runoff diversions in the delta areas,etc.).The key factor of transformation is the formation of deltas of rivers flowing into the *** of the selected stages,against the background of a gradual reduction in the area and volume of the reservoir,is characterized by the peculiarities of the formation of river deltas with the formation of genetically homogeneous sections of delta *** the period of operation of the reservoir,the delta of the main Kuban River moved up to 32.4 km and took away an area of 35.4 km^(2) of the *** the formation of the deltas of the Kuban and Belaya rivers,a bridge was formed on the Krasnodar *** evolution of the delta regions led to the division of the reservoir into two autonomous *** total area of the delta regions was 85.9 km^(2) by 2018,i.e.,21% of the initial area of the *** transformation of the Krasnodar reservoir leads to a decrease in its regulated volume and gradual degradation.

关键词： Krasnodar reservoir sedimentation siltation transformation delta formation Landsat