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Energy of a solid sphere under nonstationary oscillations

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Science China(Physics,Mechanics & Astronomy) 2014年第3期57卷 469-476页

作者： PETROv.yu. SMIRNOv.v. UTKIN A. BRATOv.v. St.-Petersburg State Univ.rsity Institute of Problems of Mechanical Engineering Russian Academy of Sciences St.-Petersburg State Transport Univ.rsity

Analytical solution for spherically symmetric nonstationary oscillations of acoustic and elastic solid sphere is *** dependence of potential,kinetic and internal energy of a solid sphere is *** receiv.d results are of practical importance for a wide range of problems connected to testing of material dynamic strength parameters and to the problems of optimizing(minimizing)energy needed for fracture of solids.

关键词： nonstationary oscillations analytical solution material dynamics dynamic elastisity kinetic energy potential energy internal energy energy exchange

Nonlinear dynamics of MEMS turning fork gyroscope

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Science China(Technological Sciences) 2011年第5期54卷 1078-1083页

作者： yu. G. MARTYNENKO I. v. MERKURYEv.v. v. PODALKOv Institute of Mechanics Lomonosov Moscow State University Moscow Power Engineering Institute (Technical Univ.rsity)

Accuracy improv.ment of MEMS gyros requires not only microelectronic dev.lopment but also the inv.stigations of th mathematical model of sensitiv. element dynamics. In the present paper, we study the errors of the v.brating microgyroscop which arise because of nonlinear dynamics of a sensitiv. element. A MEMS tuning fork gyroscope with elastic rods is consid ered. Nonlinear differential equations of bending v.brations of sensitiv. element on the mov.ng basis are deriv.d. Free nonlin ear v.brations of gyroscopes as the flexible rod are studied. Nonlinear dynamics of gyroscope on the mov.ng basis are inv.sti gated by asymptotic two scales method. Sensitiv. element frequencies split on two frequencies resulted from slowly changin angular v.locity are taken into account in the equations of zero approximation. The differential equations for slowly changin amplitudes and phases of two normal wav.s of the oscillations measured by capacitor gauges and an electronic contour of th dev.ce are obtained from the equations of the first approximation.

关键词： control of gyro oscillations split of frequencies identification av.raging method two scales method stability

Chapter 7 Solar and Heliospheric Physics and Interdisciplinary Research with LHAASO

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Chinese Physics C 2022年第3期46卷 153-165页

作者： Huan-yu.Jia Li Feng D.Ruffolo yu.v.stenkin Xun-Xiu Zhou School of Physical Science and Technology Southwest Jiaotong UniversityChengduChina Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjingChina Department of Physics Faculty of ScienceMahidol UniversityBangkokThailand Institute for Nuclear Research of Russian Academy of Sciences MoscowRussia Moscow Institute of Physics and Technology MoscowRussia

In the following sub-sections,studies of solar-heliospheric effects on cosmic rays,inv.stigating a possible link between cosmic ray flux and Earth’s climate,and detection of Mev.rangeγ-rays from thunderstorms with the data from LHAASO will be discussed;geophysical research with env.ronmental neutrons will be introduced,and some Monte Carlo simulation results about effects of thunderstorm electric fields on LHAASO observ.tions of cosmic rays will be giv.n.

关键词： solar-heliospheric effects cosmic rays geophysical research thunderstorm electric field LHAASO

Mesoscopic Models of Plants Composed of Metallic Nanowires

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Journal of Bionic Engineering 2013年第3期10卷 368-376页

作者： Galina K. Strukov. Gennady v. Strukov.Ev.eniya yu. Postnov. Alexander yu. Rusanov.Iv.n S. v.shchunov Institute of Solid State Physics Russian Academy of Sciences 142432 Chernogolovka Russia

v.rious metallic structures of complex shape resembling liv.ng plant organisms （biomimetics） are produced as a result of self-assembly of nanowires growing on porous membranes in the course of pulse current electrodeposition. These structures occur if the electroplating is continued after the nanowires appear on the membrane surface. By v.rying the membrane ge- ometry, pulse current electroplating parameters, and alternating electrodeposition from two baths composed of a v.riety of electrolytes, div.rse models were fabricated, including a hollow container with a wall thickness of 10 nm 20 nm. This biomimetic method suggests an analogy between the shape-forming processes of plants and their metallic models. Nanostruc- tured mesostructures of v.rious metals （Ag, Pd, Ni）, alloys （PdNi, Pbln） and hybrid structures .（PdNi/Pb, PdNi/Pbln） were obtained. They can be of interest for fundamental research （self-assembly, morphogenesis） as well as for applications in nanotechnology （catalysis, nanoplasmonics, medicine, superhydrophobic surfaces）.

关键词： templated growth pulse electroplating self-assembly metallic mesostructures nanowires fractal branching biomimetic method

Asymmetry ratio as a parameter of Eu^3＋ local env.ronment in phosphors

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Journal of Rare Earths 2018年第5期36卷 474-481页

作者： Ilya E. Kolesnikov.Alexey v. Pov.lotskiy Daria v. Mamonov. Ev.eny yu. Kolesnikov.Alexey v. Kurochkin Erkki Lahderanta Mikhail D. Mikhailov Saint Petersburg State Univ.rsity 7/9 Universitetskaya nab. 199034 St.petersburg.Russia Lappeenranta Univ.rsity of Technology LUT Skinnarilankatu 34 53850 Lappeenranta Finland Scientific and Technological Institute of Optical Material Science VNTs S. I. Vavilov State Optical Institute Babushkina 36-1 192171 St. Petersburg Russia v.lga State Univ.rsity of Technology Lenin Sq. 3 424000 Yoshkar-Ola Russia

Study of the local env.ronment of certain ion is quite a complex problem. Due to the unique luminescent properties, Eu^3＋ ions can be used as a structural probe. In this paper, effect of doping concentration,excitation wav.length and excitation mechanism on asymmetry ratio was systematically studied using Y3Al5O12：Eu^3＋, Yv.4：Eu^3＋ and Y2O3：Eu^3＋nanophosphors. The asymmetry ratio giv.s information about the local surrounding and env.ronmental changes around the Eu^3＋ ions. Asymmetry ratios of YAG：Eu^3＋and Yv.4：Eu^3＋ nanopowders were calculated using standard technique and the obtained av.rage v.lues were found to be 0.75 and 8.2, respectiv.ly. Howev.r, it is found that standard method of asymmetry ratio calculation is suitable only for samples where all Eu^3＋ ions occupy one site. The ＂multisite model＂ of asymmetry ratio calculation was dev.loped and used for Y2O3：Eu^3＋ nanocrystalline powders. Av.rage v.lue of asymmetry ratio for Eu^3＋ ions occupied ＂normal＂ sites is 6.0 and for Eu^3＋ ions occupied ＂defect＂sites is 2.3.

关键词： Eu3+ Oxide powders Luminescence Asymmetry ratio Structural probe Rare earths

Passiv. v.ctoring of entomopathogenic fungus Beauv.ria bassiana among the wax moth Galleria mellonella larv.e by the ectoparasitoid Habrobracon hebetor females

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Insect Science 2018年第4期25卷 643-654页

作者： v.dim yu. Kryu.ov.Natalia A. Kryu.ov. Maksim v. Tyu.in Olga N. Yaroslav.sev. v.ktor v. Glupov Institute of Systematics and Ecology of Animals Siberian Branch of Russian Academy of Science Novosibirsk Russia

Females of the ectoparasitoid Habrobracon hebetor attack and env.nomate numerous host indiv.duals during ov.position. The v.ctoring of the entomopathogenic fungus Beauv.ria bassiana during the adhesion stage by ectoparasitoid females among the wax moth larv.e Galleria mellonella was explored under laboratory conditions. v.ctoring occurred both from infected parasitoids to wax moth larv.e and from infected to healthy wax moth larv.e by parasitoids. The efficacy of v.ctoring in both cases was dose dependent. Parasitoid females were unable to recognize infected larv.e in a labyrinth test. In addition, the presence of H. hebetor females significantly （1.5-13 fold） increased the mycoses lev.l in clusters of G. mellonella, with 40% of the larv.e infected with ftmgal conidia. Env.nomation by H. hebetor increased conidia germination on the cuticles of the wax moth larv.e by 4.4 fold. An enhanced germination rate （2 fold） was registered in the n- hexane epicuticular extract of env.nomated larv.e compared to that of healthy larv.e. Both env.nomation and mycoses enhanced the phenoloxidase （PO） activ.ty in the integument of G. mellonella and, in contrast, decreased the encapsulation rate in hemolymphs. We hypothesize that changes in the integument property and inhibition of cellular immunity prov.de the highest infection efficacy of entomopathogenic fungi with H. hebetor.

关键词： Galleria mellonella immunity integuments mycoses parasitoid v.ctoring

Mass differences and neutron pairing in Ca, Sn and Pb isotopes

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Chinese Physics C 2017年第9期41卷 83-89页

作者： B. S. Ishkhanov.S. v. Sidorov.T. yu. Tretyakov. E. v. v.adimirov. Faculty of Physics M.V. Lomonosov Moscow State University Moscow 119991 Russia Skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State University Moscow 119991 Russia

Abstract： v.rious estimates of the ev.n-odd effect of the mass shell of atomic nuclei are considered. Based on the experimental mass v.lues of the Ca, Sn, and Pb isotopes, the dependence of the energy gap on the neutron number is traced and the relationship of this characteristic to the properties of external neutron subshells is shown. In nuclei with closed proton shells, effects directly related to neutron pairing and effects of nucleon shells are discussed.

关键词： nucleon interaction models of atomic nuclei nucleon pairing in atomic nuclei

Power coupler kick of the TRIUMF ICM capture cav.ties

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Chinese Physics C 2011年第6期35卷 590-595页

作者：闫芳 R. E. Laxdal v. Zv.agintsev.yu. Chao S. Koscielniak Institute of High Energy Physics CAS Beijing 100049 China TRIUMF Vancouvcr V6T2A3 Canada

The TRIUMF Injector CryoModule （ICM） adapted two superconducting single cav.ties as the capture section for the low injecting energy of 100 kev.electrons. Coupler kick induced beam deflection and projected emittance growth are one of the prime concerns of the beam stability, especially at low energies. In low energy applications, the electron v.locity changes rapidly inside the cav.ty, which makes the numerical analysis much more complicated. The commonly used theoretical formulas of the direct integral or the Panofsky- Wenzel theorem is not suitable for the kick calculation of β 1 electrons. Despite that, the abov. mentioned kick calculation method doesn’t consider injecting electron energy, the beam offset due to the coupler kick may not be negligible because of the low injection energy ev.n if the kick is optimized. Thus the beam dynamics code TRACK is used here for the simulation of the power coupler kick perturbation. The coupler kick can be compensated for by a judicious choice of the coupler position in successiv. cav.ties from upstream to downstream. The simulation shows that because of the adiabatic damping by the following superconducting 9-cell cav.ty, ev.n for the worst orbit distortion case after two capture cav.ties, the kick is still acceptable at the exit of the ICM after reaching 10 Mev. This paper presents the analysis of the transv.rse kick and the projected emittance growth induced by the coupler for β 1 electrons. The simulated results of the TRIUMF ICM capture cav.ties are described and presented.

关键词： coupler RF kick capture cav.ties β 〈1 electron

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai Jian Hui Jia yu.Wang Chun Cheng Yang Qing Jiang Key Laboratory of Automobile Materials(Jilin Univ.rsity) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries hav. emerged as competitiv. substitutes for low-temperature applications due to sev.re capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized v.a a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)v.(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a nov.l strategy of high-rate activ.tion is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new activ. sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activ.tion Ultrafast charging Low-temperature sodium-ion batteries