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Microbe social skill:the cell-to-cell communication between microorganisms

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Science Bulletin 2017年第7期62卷 516-524页

作者： Xi Zhao Xiong Liu Xin Xu yu v.Fu State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of Sciences Savaid Medical School University of Chinese Academy of Sciences

Although microbes primarily are single-cell organisms,they are not isolated *** use various means to communicate with one *** on the communication,microbes establish a social interaction with their neighbors in a specific ecological niche,and cooperative behaviors are normally performed to provide benefits on the population and species *** the microbiome era,in order to better understand the behaviors of microbes,deep understanding of the social communication between microbes hence becomes a key to interpret microbe *** we summarize the molecular mechanisms that underlie the cell-to-cell communication in prokaryotic and eukaryotic microorganisms,the recent discoveries and novel technologies in understanding the interspecies and interkingdom communication,and discuss new concepts of the sociomicrobiology.

关键词： Cell-to-cell communication Sociomicrobiology Microbial collective behavior Quorum sensing

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 University)

Accuracy improvement of MEMS gyros requires not only microelectronic development but also the investigations of th mathematical model of sensitive element dynamics. In the present paper, we study the errors of the vibrating microgyroscop which arise because of nonlinear dynamics of a sensitive element. A MEMS tuning fork gyroscope with elastic rods is consid ered. Nonlinear differential equations of bending vibrations of sensitive element on the moving basis are derived. Free nonlin ear vibrations of gyroscopes as the flexible rod are studied. Nonlinear dynamics of gyroscope on the moving basis are investi gated by asymptotic two scales method. Sensitive element frequencies split on two frequencies resulted from slowly changin angular velocity are taken into account in the equations of zero approximation. The differential equations for slowly changin amplitudes and phases of two normal waves of the oscillations measured by capacitor gauges and an electronic contour of th device are obtained from the equations of the first approximation.

关键词： control of gyro oscillations split of frequencies identification averaging method two scales method stability

Chirping instabilities produced by a runaway electron beam at a spherical tokamak

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Plasma Science and Technology 2023年第7期25卷 19-24页

作者： I M BALACHENKOv N N BAKHAREv v K GUSEv M v ILIASOvA E M KHILKEvICH P S KORENEv A E KONKOv v B MINAEv yu v MITRIZHKIN M I PATROv yu v PETROv N v SAKHAROv A E SHEvELEv O M SKREKEL Ioffe Institute Saint-Petersburg 194021Russia Lomonosov Moscow State University Moscow 119991Russia

Two different types of MHD instabilities with rapidly chirping frequency were found to arise in the Globus-M2 spherical tokamak in substantially different frequency *** first type arises at frequencies of an order of 1 MHz in ohmic plasmas at relatively low density(n_(e))ven waves,driven by electrons,accelerated during a sawtooth *** was found that the mode frequency is sweeping in time,according to the Berk-Breizman hole-clump nonlinear chirping *** second type of wave arises in a specific single-swing regime of the central solenoid current with a very narrow plasma column,when the plasma tends to decay at extremely low density(n_(e))ver the whole observed frequency range and are divided into several(two or three)frequency regions:approximately 0-30 MHz,60-120 MHz and sometimes 30-60 *** of the branches was also *** chirps are more rapid than for 1 MHz Alfven instability and follow an exponential *** paper,to our knowledge,is the first report of frequency chirping instabilities excited by accelerated electrons at a spherical tokamak.

关键词： Alfvén waves chirping instability spherical tokamak runaway electrons

Co-7Al-7v新型钴基高温合金热变形微观组织演变

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陕西科技大学学报 2025年第1期43卷 136-141页

作者：梁泽腾何宁韩正刘锦荣陆星宇李圆博李誉之陕西科技大学机电工程学院陕西西安710021

对新型钴基高温合金Co-Al-v合金进行高温热压缩变形实验,实验变形温度为800℃~1050℃,应变速率为0.001~1 s^(-1).实验结果表明在低温低应变速率(800℃,0.001 s^(-1))、较低温较高应变速率(950℃,0.1 s^(-1))和高温高应变速率(1050℃,1 s... 详细信息

对新型钴基高温合金Co-Al-v合金进行高温热压缩变形实验,实验变形温度为800℃~1050℃,应变速率为0.001~1 s^(-1).实验结果表明在低温低应变速率(800℃,0.001 s^(-1))、较低温较高应变速率(950℃,0.1 s^(-1))和高温高应变速率(1050℃,1 s^(-1))时,合金发生动态再结晶后出现孪晶,流变应力曲线也表现出达到峰值后先下降再上升的趋势,在变形温度为800℃和950℃时,高应变速率下更容易出现孪晶,随着应变速率降低,动态再结晶程度逐渐变高,在变形温度为1050℃时,低应变速率下容易出现孪晶,随着应变速率的降低,动态再结晶程度逐渐降低.随着变形温度的升高,动态再结晶程度变高,再结晶晶粒尺寸逐渐变大.通过对EBSD测试结果分析,高温低应变速率(1050℃,0.001 s^(-1))条件下的再结晶晶粒尺寸相较于高温高应变速率(1050℃,1 s^(-1))条件下的更大,高温下的孪晶界以Σ3边界为主,并且高温下应变速率越低,Σ3边界分数越高.为优化新型钴基高温合金的加工工艺提供理论依据.

关键词：新型钴基高温合金流变应力再结晶孪晶

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Determining absolute value of thermal neutron flux density based on monocrystalline silicon in nuclear reactors

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Nuclear Science and Techniques 2022年第7期33卷 133-138页

作者： v.A.varlachev E.G.Emets yu-Chen Mu E.A.Bondarenko v.A.Govorukhin National Research Tomsk Polytechnic University Tomsk634050Russia

A new type of neutron detector based on monocrystalline Si is developed to measure the fluence and flux density of thermal and fast *** principle of this detector is based on the relationship between changes in electrical conductivity and neutron fluence during ***,the absolute values of thermal neutron fluence and flux density are measured in a facile manner with high *** with activation methods,our method not only possesses a similar accuracy,but also demonstrates superior application potential for the investigation of neutron fields in nuclear reactors owing to its suitable half-life.

关键词： Thermal neutron Neutron detector Neutron flux density Cadmium difference methods

vesicular Li3v2(PO4)3/C hollow mesoporous microspheres as an efficient cathode material for lithium-ion batteries

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Nano Research 2019年第8期12卷 1937-1942页

作者： Hongxia Sun Haoran Du Mengkang yu Kuangfu Huang Nan yu Baoyou Geng College of Chemistry and Materials Science Anhui Key Laboratory of Functional Molecular SolidsMinistry of EducationThe Key Laboratory oj Electrochemical Clean Energy of Anhui Higher Education InstitutesAnhui Normal UniversityNO. 189 South Jiuhua RoadWuhu 241002China

vesicular lithium vanadium phosphate/carbon hollow mesoporous microspheres were fabricated using a facile polyvinylpyrrolidone-assisted aerosol-spray-assisted method and subsequent heat-treatment. While changing the content of polyvinylpyrrolidone, we found that carbon content was adjustable on the surface of lithium vanadium phosphate. By optimizing the carbon content among the composites, the electrochemical performance can be enhanced significantly. The results of electrochemical performance tests suggested that the samples exhibited good cycle performance and high discharge capability in the voltages between 3.0-4.8 v. The observed excellent electrochemical performances could be attributed to the proper content of carbon coating and the vesicular hollow mesoporous microsphere structure, increasing the transmission rate of lithium ions and reducing the structural change during charging and discharging effectively.

关键词： U3v2(PO4)3 aerosol-spray-assisted approach polyvinylpyrrolidone vesicular hollow microsphere electrochemical properties

Electron-beam Treatment of Tungsten-free TiC/NiCr CermetⅡ: Structural Transformations in the Subsurface Layer

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Journal of Materials Science & Technology 2006年第4期22卷 511-513页

作者： Baohai yu v.E.Ovcharenko S.G.Psakhie O.v.Lapshin Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Institute of Strength Physics and Materials Science Siberia Branch Russian Academy of Sciences Russia

The character of structural changes in the surface layer of titanium carbide （TiC） with Ni-Cr alloy binder was investigated theoretically and experimentally after electron-beam treatment of the material surface. The thermal influence of the electron-beam irradiation on the surface layer microstructure of the composite fine-grained material was mathematically analyzed. Quantitative estimations of the depth of the zone in microstructural phase transformations were carried out. The microstructure and concentration profile of Ti distribution in the metallic binder over the cross section of the surface layer with microstructural phase transformations after electron-pulse treatment of the hard metal surface were experimentally investigated.

关键词： Cermets TiC/NiCr Electron-beam treatment Structural transformation

Study Over Thermal State of Gas Turbine Engine Metal-ceramic Rotor Blades and Nozzle Guide vanes Under Thermal Shock and Thermal-cyclic Loading Conditions

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Journal of Thermal Science 2004年第2期13卷 163-166页

作者： A.v.SOUDAREv A.A. SOURYANINOv v.Ya. PODGORETS v.v.GRISHAEv v.yu. TIKHOPLAv A.S. MOLCHANOv B.v. SOUDAREv Research-Engineering "Ceramic Heat Engines" Center St.Petersburg Russia

To ensure a reliable operation of the 2.5 MW gas turbine engine (GTE- 2.5) with the inlet gas temperature TIT = 1623 K, studies were performed over the thermal state of the nozzle guide vanes and rotor blades with the temperatures, rates and flows of the working media and cooling air simulating all the potential turbine stage operating duties. The steady state and thermal-cyclic tests having been accomplished, there was no visible defect on the rotor blades and the nozzle vanes. Afterwards, they survived the endurance tests at the rated cooling. Therefore, the functionality of the shell thin-wall hybrid nozzle vanes and rotor blades under the variable operating duties of the gas turbine at the 'shock' and 'cyclic' loads of the working media temperature variations has been demonstrated.

关键词： metal-ceramic blades high temperature thermal-cyclic loading

Two-body nonleptonic decays of the heavy mesons in the factorization approach

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Frontiers of physics 2023年第6期18卷 107-126页

作者： Shuo-Ying yu Xian-Wei Kang v.O.Galkin Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China Federal Research Center“Computer Science and Control” Russian Academy of SciencesVavilov Street 40119333 MoscowRussia

In the framework of the factorization approach we calculate the branching fractions of 100 two-body nonleptonic decay channels in total,including 44 channels of the charm meson decays and 56 channels of the bottom meson *** charm meson decays,we test and confirm the previous observation that taking the limit for the number of colors N→∞significantly improves theoretical *** bottom meson decays,the penguin contributions are included in *** an essential input,we employ the weak decay form factors obtained in the framework of the relativistic quark model based on the quasi-potential *** form factors have well been tested by calculating observables in the semileptonic D and B meson decays and confronting obtained results with experimental *** general,the predictions for the nonleptonic decay branching fractions are ***,for a quantitative calculation it is necessary to account for a more subtle effects of the final-state interaction.

关键词： form factor quark model nonleptonic decay factorization method