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真空电器技术 2001年第3期 29-33页

作者： m.popov l.vander sluis

本文的目的是提供两种不同的方法模拟真空断路器（VCB）开断小感性电流所引起的电弧重燃。根据不同真空断路器的测试特性，提供两种模型，对开断模型中的空载变压器所产生的过电压进行了计算，并且统计计算了过电压的分布。

关键词：真空断路器电弧模型小感性电流高频电流

Reduction of friction by normal *** of contact stiffness

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Friction 2017年第1期5卷 45-55页

作者： m.popov V.l.popov N.V.popov Berlin University of Technology Berlin 10623 GermanyTomsk Polytechnic University Tomsk 634050 RussiaTomsk State University Tomsk 634050 Russia Berlin University of Technology Berlin 10623 Germany

The present paper is devoted to a theoretical analysis of sliding friction under the influence of oscillations perpendicular to the sliding *** contrast to previous works we analyze the influence of the stiffness of the tribological contact in detail and also consider the case of large oscillation amplitudes at which the contact is lost during a part of the oscillation period,so that the sample starts to 'jump'.It is shown that the macroscopic coefficient of friction is a function of only two dimensionless parameters-a dimensionless sliding velocity and dimensionless oscillation *** function in turn depends on the shape of the contacting *** the present paper,analysis is carried out for two shapes:a flat cylindrical punch and a parabolic *** we consider 'stiff systems',where the contact stiffness is small compared with the stiffness of the *** role of the system stiffness will be studied in more detail in a separate paper.

关键词： sliding friction out-of-plane oscillation contact stiffness coefficient of friction active control of friction

Active control of friction by transverse oscillations

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Friction 2019年第1期7卷 74-85页

作者： J.BENAD K.NAKANO V.l.popov m.popov Technische Universit?t Berlin Yokohama National University National Research Tomsk Polytechnic University National Research Tomsk State University

The present paper is devoted to a theoretical analysis of sliding friction under the influence of in-plane oscillations perpendicular to the sliding direction. Contrary to previous studies of this mode of active control of friction, we consider the influence of the stiffness of the tribological contact in detail and show that the contact stiffness plays a central role for small oscillation amplitudes. In the present paper we consider the case of a displacement-controlled system, where the contact stiffness is small compared to the stiffness of the measuring system. It is shown that in this case the macroscopic coefficient of friction is a function of two dimensionless parameters— a dimensionless sliding velocity and dimensionless oscillation amplitude. In the limit of very large oscillation amplitudes, known solutions previously reported in the literature are reproduced. The region of small amplitudes is described for the first time in this paper.

关键词： sliding friction in-plane oscillation contact stiffness coefficient of friction active control of friction

The problem and promise of scale in multilayer animal social networks

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Current Zoology 2021年第1期67卷 113-123页

作者： Alec l.ROBITAIllE Quinn m.R.WEBBER Julie W.TURNER vander WAl ERIC Department of Biology Memorial University of NewfoundlandSt.John'sNLA1B 3X9Canada Cognitive and Behavioural Ecology Interdisciplinary Program Memorial University of NewfoundlandSt.John'sNLA1B 3X9Canada

Scale remains a foundational concept in *** scale,for instance,has become a central consideration in the way we understand landscape ecology and animal space ***,scale-dependent social processes can range from fine scale interactions to co-occurrence and overlapping home ***,sociality can vary within and across *** networks promise the explicit integration of the social,spatial,and temporal *** the complex interplay of sociality and animal space use in heterogeneous landscapes,there remains an important gap in our understanding of the influence of scale on animal social *** an empirical case study,we discuss ways of considering social,spatial,and temporal scale in the context of multilayer caribou social *** integration of social and spatial processes,including biologically meaningful scales,within the context of animal social networks is an emerging area of *** incorporate perspectives that link the social environment to spatial processes across scales in a multilayer context.

关键词： caribou habitat selection landscape ecology Rangifer social network analysis space use

Development of high-coercivity state in melt-spun Fe41Pd41B8Si6P4 ribbons

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Rare metals 2020年第1期39卷 76-83页

作者： Oksana Aleksandrovna Golovnia Nina Ivanovna Vlasova Aleksandr Gervasievich popov Vasiliy Semenovich Gaviko Vladimir Vladimirovich popov Jr. Andrey Vladimirovich Protasov Arti Kashyap m.N.miheev Institute of metal Physics of Ural Branch of Russian Academy of Sciences EkaterinburgRussia620990 Institute of Natural Sciences and mathematics Ural Federal UniversityEkaterinburgRussia620002 Israel Institute of metals Technion R&D FoundationTechnion City3200003HaifaIsrael Indian Institute of Technology mandi KamandMandiHP175005India

The phase transformation and magnetic hysteresis properties of melt-spun Fe41 Pd41 B8 Si6 P4 ribbons subjected to the annealing at temperatures of 500-550℃were studied after holding for 0.1-60.0 h by transmission electron microscopy(TEm),X-ray diffraction(XRD)and thermomagnetic *** additions of P,B and Si to the FePd alloy allowed us to achieve the coercivity of124 kA·m-1,which is 2.6 times higher than that of the melt-spun ribbons of the binary equiatomic FePd *** high-coercivity Fe41Pd41B8 Si6 P4 alloy is nanocrystalline and is composed of the ordered l10-phase grains approximately 40 nm in size and inclusions of the Fe2(P,B)and Pd2(Si,B)*** coercivity kinetics is controlled by the phase transformation which can be divided into three stages:transformation from the bcc structure to nanosized regions of the fee and Fe2 P phases;transformation from the fee to l10 nanosized regions with somewhat different degrees of tetragonality and their ordering;and extensive growth of the weight fraction of l10 phase from the fee nanosized regions.P and B atoms occupy interstitial sites in the iron plane of l10 lattice,thus decreasing its Curie temperature(TC).

关键词： Fe-Pd-P-B-Si melt spinning l10 Nanostructured materials Phase transformation magnetic measurements

NSVS 2569022:a peculiar binary among W Uma stars with extremely small mass ratios

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Research in Astronomy and Astrophysics 2018年第10期18卷 123-130页

作者： Diana P.Kjurkchieva Velimir A.popov Nikola I.Petrov Department of Physics and Astronomy Shumen University Institute of Astronomy and NAO Bulgarian Academy of Sciences

Photometric observations of the W Uma binary NSVS 2569022 are presented. The light curve solution reveals that both components are of F spectral type （temperatures T1 = T2 = 6100 K）. NSVS 2569022 undergoes a total eclipse of W subtype and the mass ratio is well-determined. Its extremely small value of only 0.077 implies that the target will probably experience instability and a possible merger. This value ranks NSVS 2569022 in sixth place among binaries with the smallest mass ratio. Based on an empirical relation of ＂period - total mass＂ for low mass-ratio binaries, we estimate the global parameters of NSVS 2569022： masses m1 = 1.17 m⊙ and m2 = 0.09 m⊙; radii R1 = 1.19 R⊙ and R2 = 0.38 R⊙; luminosities l1 = 1.73 l⊙ and l2 = 0.17l⊙. An analysis of the characteristics of binaries with extremely low-mass ratios is made. NSVS 2569022 turns out to be a peculiar binary among W Uma stars with extremely small mass ratios due to its unexpectedly small fill-out factor of only 0.014 （slightly overcontact configuration）.

关键词： binaries eclipsing - binaries close - stars fundamental parameters - stars individual(NSVS 2569022)

Aryl Hydrocarbon Receptor is Involved in the Proinflammatory Cytokine Response to Cadmium

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Biomedical and Environmental Sciences 2021年第3期34卷 192-202页

作者： KUlAS Jelena TUCOVIC Dina ZElJKOVIC milica popovIC Dusanka popov AlEKSANDROV Aleksandra KATARANOVSKI milena mIRKOV Ivana Immunotoxicology Group Department of EcologyInstitute for Biological Research‘Sinisa Stankovic'-National Institute of Republic of SerbiaUniversity of Belgrade142 Bulevar despota StefanaBelgrade 11000Serbia

Objective To investigate involvement of the aryl hydrocarbon receptor(Ah R)in the immunomodulatory effects of cadmium(Cd).methods The effect of Cd on Ah R activation(CYP1 A1 and CYP1 B1 m RNA expression)was examined in lung leukocytes of Cd-exposed rats(5 and 50 mg/l,30 d orally)and by in vitro leukocyte *** involvement of Ah R signaling in the effects of Cd on the interleukin(Il)-1β,Il-6,and tumor necrosis factor(TNF)lung leukocyte response was investigated in vitro using the receptor antagonist *** Cd increased CYP1 B1(in vivo and in vitro)and CYP1 A1(in vitro)m RNA,indicating Ah R involvement in the action of *** response to Cd,lung leukocytes increased Il-6 and decreased TNF at the gene expression and protein levels,but decreased Il-1βproduction due to reduced *** Ah R antagonist CH-223191 abrogated the observed effects of Cd on the cytokine *** absence of Ah R reactivity and cytokine response to Cd of leukocytes from the lungs of a rat strain that is less sensitive to Cd toxicity coincided with a high Ah R repressor m RNA *** Ah R signaling is involved in the lung leukocyte proinflammatory cytokine response to *** relevance of the Ah R to the cytokine response to Cd provides new insight into the mechanisms of Cd immunotoxicity.

关键词： Cadmium lung leukocytes Aryl hydrocarbon receptor Cytokine(Il-6,TNF,Il-1β)response

Regulation of dipeptidyl peptidase 8 and 9 expression in activated lymphocytes and injured liver

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World Journal of Gastroenterology 2013年第19期19卷 2883-2893页

作者： Sumaiya Chowdhury Yiqian Chen Tsun-Wen Yao Katerina Ajami Xin m Wang Yury popov Detlef Schuppan Patrick Bertolino Geoffrey W mcCaughan Denise mT Yu mark D Gorrell Centenary Institute and Sydney medical School University of SydneySydneyNSW 2006Australia Division of Gastroenterology and Hepatology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02215United States molecular Hepatology Centenary InstituteNewtownSydneyNSW 2042Australia

AIm:To investigate the expression of dipeptidyl peptidase(DPP) 8 and DPP9 in lymphocytes and various models of liver ***:DPP8 and DPP9 expression were measured in mouse splenic CD4 + T-cells,CD8 + T-cells and B-cells(B220 +),human lymphoma cell lines and mouse splenocytes stimulated with pokeweed mitogen(PWm) or lipopolysaccharide(lPS),and in dithiothreitol(DTT) and mitomycin-C treated Raji ***8 and DPP9 expression were measured in epidermal growth factor(EGF) treated Huh7 hepatoma cells,in fibrotic liver samples from mice treated with carbon tetrachloride(CCl 4) and from multidrug resistance gene 2(mdr2 /Abcb4) gene knockout(gko) mice with biliary fibrosis,and in human end stage primary biliary cirrhosis(PBC).RESUlTS:All three lymphocyte subsets expressed DPP8 and DPP9 ***8 and DPP9 expression were upregulated in both PWm and lPS stimulated mouse splenocytes and in both Jurkat T-and Raji B-cell ***8 and DPP9 were downregulated in DTT treated and upregulated in mitomycin-C treated Raji ***9transfected Raji cells exhibited more annexin V + cells and associated ***8 and DPP9 mRNA were upregulated in CCl 4 induced fibrotic livers but not in the lymphocytes isolated from such livers,while DPP9 was upregulated in EGF stimulated Huh7 *** contrast,intrahepatic DPP8 and DPP9 mRNA expression levels were low in the mdr2 gko mouse and in human PBC compared to non-diseased ***:These expression patterns point to biological roles for DPP8 and DPP9 in lymphocyte activation and apoptosis and in hepatocytes during liver disease pathogenesis.

关键词： Dipeptidyl peptidase CD26 lymphocytes liver fibrosis Biliary fibrosis

Bright betatron radiation from direct-laseraccelerated electrons at moderate relativistic laser intensity

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matter and Radiation at Extremes 2021年第4期6卷 10-17页

作者： O.N.Rosmej X.F.Shen A.Pukhov l.Antonelli F.Barbato m.Gyrdymov m.m.Gunther S.Zahter V.S.popov N.G.Borisenko N.E.Andreev GSI Helmholtzzentrum fur Schwerionenforschung GmbH Planckstraße164291 DarmstadtGermany Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany Helmholtz Forschungsakademie Hessen fur FAIR(HFHF) Campus Frankfurt am MainMax-von-Laue-Straße 1260438 Frankfurt am MainGermany Heinrich-Heine-University Dusseldorf Universitatsstraße 1DusseldorfGermany York Plasma Institute University of YorkChurch LaneHeslingtonYork YO105DQUnited Kingdom University of Bordeaux CNRSCEACELIAUMR 5107F-33405 TalenceFrance Joint Institute for High Temperatures RASIzhorskaya St.13Bldg.2125412 MoscowRussia moscow Institute of Physics and Technology(State University) Institutskiy Pereulok 9141700 DolgoprudnyMoscow RegionRussia P.N.lebedev Physical Institute RASLeninsky Prospekt 53119991 MoscowRussia

Direct laser acceleration(DlA)of electrons in a plasma of near-critical electron density(NCD)and the associated synchrotron-like radiation are discussed for moderate relativistic laser intensity(normalized laser amplitude a0≤4.3)and ps length *** regime is typical of kJ PW-class laser facilities designed for high-energy-density(HED)*** experiments at the PHElIX facility,it has been demonstrated that interaction of a 1019 W/cm2 sub-ps laser pulse with a sub-mm length NCD plasma results in the generation of high-current well-directed superponderomotive electrons with an effective temperature ten times higher than the ponderomotive potential[Rosmej et al.,Plasma *** Fusion 62,115024(2020)].Three-dimensional particle-in-cell simulations provide good agreement with the measured electron energy distribution and are used in the current work to study synchrotron radiation from the DlA-accelerated *** resulting x-ray spectrum with a critical energy of 5 keV reveals an ultrahigh photon number of 731011 in the 1–30 keV photon energy range at the focused laser energy of 20 *** simulations of betatron x-ray phase contrast imaging based on the DlA process for the parameters of a PHElIX laser are *** results are of interest for applications in HED experiments,which require a ps x-ray pulse and a high photon flux.

关键词： intensity relativistic critical

Prompt neutron emission in ^(250)No spontaneous fission associated with ground and isomeric state decays

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Chinese Physics C 2024年第6期48卷 112-117页

作者： R.S.mukhin A.V.Isaev A.V.Andreev m.l.Chelnokov V.I.Chepigin H.m.Devaraja I.N.Izosimov A.A.Kuznetsova O.N.malyshev A.G.Popeko Yu.A.popov A.Rahmatinejad B.Sailaubekov T.m.Shneidman E.A.Sokol A.I.Svirikhin m.S.Tezekbayeva m.A.Bychkov A.V.Yeremin O.Dorvaux B.Gall K.Kessaci K.Hauschild A.lopez-martens Joint Institute for Nuclear Research Dubna141980Russia Dubna State University Dubna141982Russia Institute of Nuclear Physics Almaty050032Kazakhstan l.N.Gumilyov Eurasian National University Astana010008Kazakhstan Kazan Federal University Kazan420008Russia Universitéde Strasbourg CNRSStrasbourg67000France IJClab IN2P3-CNRSUniversitéParis-SaclayOrsay91400France

The complete-fusion reaction^(204)Pb(^(48)Ca,2n)^(250)No was used to study two activities of^(250)No with distinct half-lives.A total of 1357 events were observed in the SFiNx neutron detection *** average number of neutrons emitted per spontaneous fission of^(250)No was determined to be(4.1±0.1).The unusually symmetrical shape of the prompt neutron multiplicity distribution was restored and presented for the first *** tests were performed to compare the prompt neutron multiplicity distributions associated with the ground state and K-isomer state decays.

关键词： spontaneous fission prompt neutrons actinide