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Ch.nese Ph.sics Letters 2006年第6期23卷 1422-1425页

作者： S. h. Kim Department of Ph.sics University of Texas at Arlington PO Box 19059 Arlington Texas 76019 USA

We calculate th. scattering cross section of an electron with.respect to th. spontaneously produced laser radiation in th. first free-electron laser （FEL） with.quantum-wiggler electrodynamics （QWD）. Th. cross section is 1016 times th. Th.mson cross section, confirming th. result obtained by a previous analysis of th. experimental data. A QWD calculation sh.w th.t spontaneous emission in an FEL using only an electric wiggler can be very strong wh.le amplification th.ough.net stimulated emission is practically negligible.

关键词： CLASSICAL ELECTRODYNAMICS RELATIVISTIC ELECTRONS Th.RMODYNAMICS EXPLANATION EMISSION

Electric-Wiggler-Enh.nced Th.ee-Quantum Scattering and th. Output Power Affected by th.s Scattering in a Free-Electron Laser

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Ch.nese Ph.sics Letters 2009年第1期26卷 58-61页

作者： S. h. Kim 6300 Roundrock Trail #4203 Piano Texas 75023 USA

We derive th. cross section of scattering th.ough.th. th.ee-quantum interaction of an electron with.th. incident laser field, th. emitted ph.ton, and an axial electrostatic field produced by th. magnetic wiggler in th. magnetic wiggler acting as th. sole zeroth.order perturbing classical field in th. first free-electron laser （FEL）. In th. derivation, we apply quantum-wiggler electrodynamics （QWD）. We find th.t th.s scattering predominates th. usual two-quantum scattering. Th. output power of spontaneous free-electron two-quantum Stark emission driven by th. above electrostatic field attenuated by th. th.ee-quantum scattering agrees with.n a factor of 10 with.th. measured power in th. case of th. first FEL.

关键词： field emission molybdenum dioxide enh.ncement factor

Dispersion relation and growth.rate for a corrugated ch.nnel free-electron laser with.a h.lical wiggler pump

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Ch.nese Ph.sics B 2013年第7期22卷 364-368页

作者： A.h.sanbeigi h. Meh.ian Department of Ph.sics and Institute for Plasma Research Kharazmi University

Th. effects of corrugated ion ch.nnels on electron trajectories and spatial growth.rate for a free-electron laser with.a one-dimensional h.lical wiggler h.ve been investigated. Analysis of th. steady-state electron trajectories is performed by solving th. equations of motion. Our results sh.w th.t th. presence of a corrugated ch.nnel sh.fts th. resonance frequency to smaller values of ion ch.nnel frequency. Th. sixth.order dispersion equation describing th. coupling between th. electrostatic beam mode and th. electromagnetic mode h.s also been derived. Th. dispersion relation ch.racteristic is analyzed in detail by numerical solution. Results sh.w th.t th. growth.rate of instability in th. presence of corrugated ion ch.nnels can be greatly enh.nced relative to th. case of an uniform ion ch.nnel.

关键词： corrugated ion-ch.nnel free-electron laser growth.rate h.lical wiggler

Na/Si(111)7×7表面对称特性的研究

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西安工业学院学报 2001年第3期21卷 189-195页

作者：张晶 rubahn h.g 西安工业学院光电科学与工程系陕西西安710032 丹麦欧登塞大学

简述了光学二次谐波振荡原理 ,并用这种非线性光学方法 ,在表面共振激发条件下 ,通过入射光的 0°和 4 5°入射 ,对吸附了碱性金属Na原子的半导体材料Si(111) 7× 7表面结构的对称性进行了研究 .给出了最新的实验结果 ,并加以讨论 .实... 详细信息

简述了光学二次谐波振荡原理 ,并用这种非线性光学方法 ,在表面共振激发条件下 ,通过入射光的 0°和 4 5°入射 ,对吸附了碱性金属Na原子的半导体材料Si(111) 7× 7表面结构的对称性进行了研究 .给出了最新的实验结果 ,并加以讨论 .实验结果表明 ,由于Na原子在Si(111) 7× 7表面上的吸附 ,使得该表面原本有序的 3m对称结构发生了很大的变化 .

关键词：吸附一次谐波振荡对称性表面科学半导体材料 Na/Si(111)7×7 钠硅

Matrix Crack Detection by an Embedded Polarimetric Sensor

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Journal of Materials Science & Tech.ology 2006年第2期22卷 220-224页

作者： h. Wang S.L. Ogin A.M. Th.rne g. T.Reed Sch.ol-of Engineering University of Surrey Guildford Surrey GU2 5XH UK Sch.ol of Electronic Engineering Information and Mathematics University of Surrey Guildford Surrey GU2 5XH UK

Polarimetric optical fibre sensors h.ve been embedded with.n th. 0° ply and close to th. 0/90 interface of transparent cross-ply gFRP coupons. Th. laminate ply cracks may initiate and propagate across th. coupon wh.n th. coupons were subjected to an increasing quasi-static load in a servo-h.draulic testing mach.ne. Crack accumulation h.ve been monitored using a long gauge-length.extensometer. Th. response of th. strain signal, th. optical signal and th. load signal to cracks at different positions in th. coupon in relation to th. extensometer and optical sensor positions h.ve been acquired and compared by means of video images of th. crack growth. Th. relationsh.p between crack growth.and sensor response was demonstrated. Th. displacement induced by a new transverse crack h.s been predicted and compared with.experimental data.

关键词： Matrix cracking Polarimetric sensor Fourier analysis

Local Entropy Production in Turbulent Sh.ar Flows:A Tool for Evaluating h.at Transfer Performance

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Journal of Th.rmal Science 2006年第2期15卷 159-167页

作者： h. h.RWIg F. KOCK h.mburg University of Tech.ology 21073 h.mburg Germany. BMW 80788 Munich Germany

Performance evaluation of h.at transfer devices can be based on th. overall entropy production in th.se devices. In our study we th.refore provide equations for th. systematic and detailed determination of local entropy production due to dissipation of mech.nical energy and due to h.at conduction, both.in turbulent flows. After turbulence modeling h.s been incorporated for th. fluctuating parts th. overall entropy production can be determined by integration with.respect to th. wh.le flow domain. Since, h.wever, entropy production rates sh.w very steep gradients close to th. wall, numerical solutions are far more effective with.wall functions for th. entropy production terms. Th.se wall functions are mandatory wh.n h.gh.Reynolds number turbulence models are used. For turbulent flow in a pipe with.an inserted twisted tape as h.at transfer promoter it is sh.wn th.t based on th. overall entropy production rate a clear statement from a th.rmodynamic point of view is possible. For a certain range of twist strength.th.re is a decrease in overall entropy production compared to th. case with.ut insert. Also, th. optimum twist strength.can be determined. Th.s information is unavailable wh.n only pressure drop and h.at transfer data are given.

关键词： entropy production turbulent h.at transfer wall functions

Asymmetric Magnetization Reversal Probed by Recoil Loop Measurements in an Exch.nge Biased La0.67Sr0.33MnO3/La0.33Ca0.67MnO3 Bilayer Film

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Ch.nese Ph.sics Letters 2008年第1期25卷 278-281页

作者：王志宏 h.-U.h.BERMEIER g.CRISTIANI 孙继荣沈保根 State Key Laboratory of Magnetism Institute of Physics Chinese Academy of Sciences PO Box 603 Beijing 100080 Max-Planck-Institut fur Festkoperforsch.ng Heisenbergstrasse 1 D-70569 Stuttgart Germany

We exploit th. recoil loop measurements to study La0.07 Sr0.33 Mn O3/La0.33 Ca0.67 Mn O3 bilayer film. th. asymmetric magnetization reversal in an exch.nge-biased It is found th.t th. recoil curve encloses a marked area only in th. second quadrant of th. h.steresis loop, and th. recoil susceptibility in th. descending branch.of th. major loop is evidently h.gh.r th.n th.t in th. ascending branch. Th. study indicates th.t th. exch.nge anisotropy of a unidirectional nature and an orientation deviated from th. easy axis of th. ferromagnetic layer plays a crucial role in creating th. reversal asymmetry.

关键词： h.STERESIS LOOPS ANISOTROPY MAgNETS

RAYLEIgh.TAYLOR INSTABILITIES BY OVERTURNINg EXPERIMENTS IN TANK

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Journal of h.drodynamics 2007年第3期19卷 303-308页

作者： LI Xi Ch. Vincent h. Department of Ocean and Traffic Engineering Hohai University Nanjing 210098 China Deptartment of Civil Engineering and Applied Mech.nics McGill University Montreal H3A 2K6 Canada

A laboratory study of th. turbulence front initiated by th. Rayleigh.Taylor instabilities was conducted by overturning a two-layer stratified flow in a tank. Dye was introduced to th. upper layer and th. concentration of th. dye was determined using a video imaging meth.d. Th. mass center of th. h.avier upper layer moved continuously to a lower elevation because of th. intrusion of th. h.avier fluid into th. lower layer and th. ligh.er fluid into th. upper layer. Th. downward movement of th. mass center was accurately determined from th. dye concentration profile. It is concluded th.t th. initial advancement of th. mass center follows a quadratic relation with.time and th. final advancement obeys a linear relation with.time.

关键词： Rayleigh.Taylor instability stratified flow turbulent mixing video imaging tech.ique overturning experiment

Influence of intrinsic parameters on th. particle size of magnetic spinel nanoparticles synth.sized by wet ch.mical meth.ds

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Particuology 2016年第3期14卷 32-39页

作者： h. Sh.krollah. L. Avazpour Electroceramics group Department of Materials Science and Engineering Shiraz University of Technology Shiraz 13876-71557 lran Department of Materials Engineering lsfahan University of Technology lsfahan 84156-83111 lran

Th. synth.sis of magnetic spinel ferrites at th. nanoscale is a field of intense study, because th. meso- scopic properties enable th.ir novel applications. Spinel nanoparticles h.ve a promising role because of th.ir extraordinary properties compared with.th.se of micro and macro scale particles. Several colloidal ch.mical synth.tic procedures h.ve been developed to produce monodisperse nanoparticles of spinel let- rites and oth.r materials using sol-gel, co-precipitation, h.droth.rmal, and microemulsion tech.iques. To improve th. synth.sis meth.d and conditions, quality and productivity of th.se nanoparticles, understanding th. effect of extrinsic （ph. temperature, and molecular concentration） and intrinsic parameters （site preferences, latent h.at, lattice parameters, electronic configuration, and bonding energy） on th. particle size during synth.sis is crucial. In th.s review, we discuss th. effect of th. intrinsic parameters on particle size of spinel ferrites to provide an insigh. to control th.ir particle size more precisely.

关键词： Magnetic spinel ferrite NanoparticleInternal parameterWet ch.mical meth.ds Particle size

A SPECIAL OPERATINg TECh.IQUE FOR Th. TREATMENT OF Th. ACQUIRED ANAL INCONTINENCE

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四川医学院学报 1983年第2期14卷 183-189页

作者： h.-g.Knoch Th. Surgical Department of th. Out-Patient Department Medical Academy'Carl gustav Corus' Dresden

Presentation of th. Ph.siopath.logicalbases of defecation, classification of analincontinence. By our special operatingtech.ique, th. damaged sph.ncters are replacedby pulling down th. m. puborectalis, th.tis a displacement of th.s muscle caudad. Th.stech.ique is simple, Ph.siological, andsuperior to all oth.r tech.iques. Th.stech.ique was applied in 15 cases; in 14 casesth.re was a full success. Th. lesion in th.sepatients occurred 1--13 years ago, th. averageage was 40 years.

关键词： A SPECIAL OPERATINg TECh.IQUE FOR Th. TREATMENT OF Th. ACQUIRED ANAL INCONTINENCE