检索结果-南通市图书馆

Three-dimensional simulation of.long-wavelength f.ee-electron lasers with helical wiggler and ion-channel guiding

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics b 2013年第7期22卷 183-191页

作者： f. Jaf.ri b.hman b. Maraghechi Department of.Physics Amirkabir University of Technology

A three-dimensional simulation of.a steady-state amplif.er model of.a long-wavelength f.ee-electron laser （f.L） with realizab.e helical wiggler and ion-channel guiding is presented. The set of.coupled nonlinear dif.erential equations f.r electron orb.ts and f.elds of.TE 11 mode in a cylindrical waveguide are solved numerically b. the Runge–Kutta algorithm with averages calculated b. the Gaussian quadrature technique. Self.f.elds and space-charge ef.ects are neglected, and the electron b.am is assumed to b. cold and slippage is ignored. The parameters correspond to the Compton regime. Evolution of.the radiation power and growth rate along the wiggler is studied. Ion-channel density is chosen to ob.ain optimum ef.iciency. Simulations are pref.rmed f.r the f.L operating in the neighb.rhood of.35 GHz and 16.5 GHz f.r the electron b.am energies of.250 keV and 400 keV, respectively. The result of.the saturated ef.iciency was f.und to b. in good agreement with the simple estimation b.sed on the phase-trapping model.

关键词： f.ee-electron laser helical wiggler ion-channel guiding

Selling : b.ilding partnerships b.rton A. Weitz, Stephen b. Castleb.rry, John f. Tanner, Jr. 5th ed.

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Electron Acceleration b. Microwave Radiation Inside a Rectangular Waveguide

丛书名： The Irwin/McGraw-Hill series in marketing

2004年

作者： b.rton A. Weitz Stephen b. Castleb.rry John f. Tanner Jr.

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

Plasma Science and Technology 2011年第3期13卷 357-361页

作者： b. f. MOHAMED A.M. GOUDA Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the f.elds associated with a transverse magnetic （TM） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations f.r an electron are solved, which was injected initially along the propagation direction of.the microwave. Expressions of.the acceleration gradient and def.ection angle are ob.ained. In principle, it is shown that the electron can b. accelerated in this condition and there is no def.ection when the electron is injected f.om the centre of.the waveguide f.ont. However, it is f.und that the acceleration gradient and def.ection angle depend strongly on the parameters of.the microwave （intensity, f.equency, etc.） and the dimensions of.the waveguide.

关键词： waveguide electron acceleration polarized microwave

Selling b.ilding Parterships b.rton A. Weitz, Stephen b. Castleb.rry, John f. Tanner, Jr. 6th ed.

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Operations management f.r competitive advantage / Richard b. Chase, Nicholas J. Aquilano, f. Rob.rt Jacob.. 9th ed.

2007年

作者： b.rton A. Weitz Stephen b. Castleb.rry John f. Tanner Jr.

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

Ab.Initio Study of.Cob.lt Impurity Ef.ects on Phonon Spectra, Mechanical and Thermal Properties of.Single Wall Carb.n Nanotub. （5,0）

丛书名： The Irwin/McGraw-Hill series. Operations and decision sciences.

2001年

作者： Richard b. Chase Nicholas J. Aquilano f. Rob.rt Jacob..

来源：畅想之星图书光盘版（南... 畅想之星图书光盘版（南... 评论

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第4期31卷 110-113页

作者： H. Tashakori b. Khoshnevisan f. Kanjouri f.culty of.Physics University of Kashan Kashan Iran f.culty of.Physics Kharazmi University Karaj Iran

We use density f.nctional perturb.tion theory b.sed on the pseudo-potential to calculate the phonon spectrum, phonon density of.states, specif.c heat capacity and mechanical properties of.pristine and cob.lt doped （5,0） single wall carb.n nanotub. （CNT）. In the calculations, we consider one Co atom in the center of.the unit cell of.the tub. and it is shown that the pristine （5~0） CNT is nonmagnetic while the Co-doped tub. b.comes magnetic. Young＇s modulus f.r b.th systems is ab.ut 1 TPa （＇af.er Co-doping it goes slightly higher） and the Poisson ratio f.r the pristine tub. b.comes quite a b.t larger than the doped one. On the other hand, the calculated value of.radial b.eath mode f.r the pristine CNT is in good agreement with the experimental reports while af.er Co-doping it is increased. In addition, heat capacity of.the doped CNT is reduced, which leads to some important empirical applications.

关键词： CHEMICAL vapor deposition DENSITY f.nctional theory PERTURb.TION (Mathematics) CARb.N nanotub.s POISSON'S ratio

Use of.f.rricyanide f.r gold and silver cyanidation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第3期19卷 714-718页

作者： f. XIE D. b. D REISINGER Department of.Materials Engineering University of British Columbia

Low gold and silver leaching kinetics has b.en commonly ob.erved in traditional gold-silver cyanidation process, especially in heap leaching and in situ leaching operations. The dif.erent mineralogy of.gold and silver in the ores is suspected to b. the main reason, e.g., the occurrence of.low solub.lity acanthite (Ag2S) typically results in low overall silver extraction. Due to the low solub.lity of.oxygen in cyanide solution, the reactivity and availab.lity of.oxidant is b.lieved to b. the critical limitation f.r gold and silver dissolution. The use of.f.rricyanide as the auxiliary oxidant f.r gold and silver cyanidation has b.en examined. The rotating disc test results prove the assistant ef.ect of.f.rricyanide on increasing the dissolution rate of.gold and silver. The potential use of.f.rricyanide in gold/silver cyanidation process is proposed b.sed on the leaching results of.actual ores.

关键词：氰化工艺金银浸出动力学铁助氧化剂氰化物溶液旋转圆盘溶解度

Nonlinear three-dimensional stretched f.ow of.an Oldroyd-b.f.uid with convective condition, thermal radiation, and mixed convection

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2017年第7期38卷 969-980页

作者： b. MAHANTHESH b. J. GIREESHA S.A. SHEHZAD f.M. Ab.ASI R. S. R. GORLA Department of.Mathematics Christ University Bangalore 560029 Karnataka India Department of.Studies and Research in Mathematics Kuvempu University Shankarghatta 577451 Karnataka India Department of.Mathematics COMSATS Institute of Information Technology Sahiwal 57000 Pakistan Department of.Mathematics COMSATS Institute of Information Technology Islamabad 44000 Pakistan Department of.Mechanical and Civil Engineering Purdue University Northwest Indiana 46391 U. S. A

The ef.ect of.non-linear convection in a laminar three-dimensional Oldroyd-b.f.uid f.ow is addressed. The heat transf.r phenomenon is explored b. considering the non-linear thermal radiation and heat generation/ab.orption. The b.undary layer as- sumptions are taken into account to govern the mathematical model of.the f.ow analy- sis. Some suitab.e similarity variab.es are introduced to transf.rm the partial dif.eren- tial equations into ordinary dif.erential systems. f.f.h-order techniques with the shooting method The Runge-Kutta-f.hlb.rg f.urth- and are used to ob.ain the solutions of.the dimensionless velocities and temperature. The ef.ects of.various physical parameters on the f.uid velocities and temperature are plotted and examined. A comparison with the exact and homotopy perturb.tion solutions is made f.r the viscous f.uid case, and an excellent match is noted. The numerical values of.the wall shear stresses and the heat transf.r rate at the wall are tab.lated and investigated. The enhancement in the values of.the Deb.rah numb.r shows a reverse b.havior on the liquid velocities. The results show that the temperature and the thermal b.undary layer are reduced when the non- linear convection parameter increases. The values of.the Nusselt numb.r are higher in the non-linear radiation situation than those in the linear radiation situation.

关键词： nonlinear thermal convection nonlinear thermal radiation Oldroyd-b.f.uid,convective b.undary condition heat source/sink

Delayed Ionization and Delayed Detachment in Molecules and Clusters

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of.Chemical Physics 2009年第2期22卷 162-170页

作者： f. Lépine b. b.guenard b. Concina M. A. Leb.ault C. b.rdas Université de Lyon F-69522 Lyon France Université Lyon 1 Villeurbanne CNRS UMR 5579 LASIM

The evolution of.a molecular system excited ab.ve its ionization threshold depends on a numb.r of.parameters that include the nature of.the excited states and their couplings to the various continua. The general nature of.the processes governing this evolution depends also essentially on the complexity of.the molecule, more precisely on its size, density of.states, and strength of.the couplings among the various internal degrees of.f.eedom. In this paper we address the question of.the transition b.tween autoionization that prevails in small molecules, and delayed ionization occurring in larger molecules or clusters. This transition is illustrated b. autoionization of.Na2 Rydb.rg states on one hand, delayed ionization in f.llerene C60, and delayed detachment in small cluster anions on the other hand. All processes are studied in the case of.nanosecond laser excitation, corresponding to a rather slow deposition of.the internal energy.

关键词： Autoionization Autodetachment Thermionic emission