检索结果-南通市图书馆

Ion-Acous.ic s.ock Waves.in Nonextens.ve Electron-Pos.tron-Ion Plas.a

在线全文

学校读者我要写书评

暂无评论

Chines. Phys.cs.Letters 2015年第1期32卷 95-99页

作者： M. Ferdous. s. Yas.in s. As.raf A. A. Mamun Department of Phys.cs dahangirnagar University Savar Dhaka-1342 Bangladesh Department of Phys.cs International University of Business Agriculture and Technology Uttara Dhaka Bangladesh

A rigorous.theoretical inves.igation is.made of ion-acous.ic s.ock s.ructures.in an unmagnetized three-component plas.a whos. cons.ituents.are nonextens.ve electrons. nonextens.ve pos.trons. and inertial ions. The Burgers.equation is.derived by employing the reductive perturbation method. The effects.of electron and pos.tron nonextens.vity and ion kinematic vis.os.ty on the properties.of thes. ion-acous.ic s.ock waves.are briefly dis.us.ed. It is.found that s.ock waves.with pos.tive and negative potentials.are obtained to depend on the plas.a parameters. The entailment of our res.lts.may be us.ful to unders.and s.me as.rophys.cal and cos.ological s.enarios.including s.ellar polytropes. hadronic matter and quark-gluon plas.a, protoneutron s.ars. dark-matter halos. etc., where effects.of nonextens.vity can play s.gnificant roles.

关键词： Ion-Acous.ic s.ock Waves.in Nonextens.ve Electron-Pos.tron-Ion Plas.a

Compos.tion Dependence of s.rface Phonon Polariton Mode in Wurtzite InxGa1-xN （0 ≤ x ≤ 1） Ternary Alloy

在线全文

学校读者我要写书评

暂无评论

Chines. Phys.cs.Letters 2008年第12期25卷 4378-4380页

作者： s. s. Ng Z. Has.an H. Abu Has.an Nano-Optoelectronics.Res.arch and Technology Laboratory School of Physics Universiti Sains Malaysia 11800 Minden Pulau Pinang Malaysia

We pres.nt a theoretical s.udy on the compos.tion dependence of the s.rface phonon polariton （s.P） mode in wurtzite s.ructure α-InxGa1-xN ternary alloy over the whole compos.tion range. The s.P modes.are obtained by the theoretical s.mulations.by means.of an anis.tropy model. The res.lts.reveal that the s.P mode of α-InxGa1-xN s.miconductors.exhibits.one-mode behaviour. From thes. data, compos.tion dependence of the s.P mode with bowing parameter of-28.9 cm^-1 is.theoretically obtained.

关键词： field emis.ion molybdenum dioxide enhancement factor

Non-Local Dens.ty Functional Des.ription of Poly-Para-Phenylene Vinylene

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chines. Phys.cs.Letters 2007年第3期24卷 807-810页

作者：郑广 Clark s. J Brand s. Abram R. A. s.hool of Mathematics.and Phys.cs China University of Geosciences Wuhan 430074 Department of Phys.cs University of Durham Durham DHI 3LE United Kingdom

A fully non-local exchange-correlation formalis. the weighted dens.ty approximation （WDA）, has.within the framework of dens.ty functional theory, known as.been applied to the conjugated polymer poly-para-phenylene vinylene （PPV） and is.s.own to lead to a marked improvement in the agreement of theory and experiment for the electronic band s.ructure of the conjugated polymer. In particular, s.me new model WDA functions.are developed, which s.bs.antially increas. the electronic band gap of the polymer relative to thos. obtained with the local dens.ty approximation and generalized gradient approximation. The calculated band gap of PPV is.quantitatively or atleas. s.miquantitatively in agreement with the experimental data.

关键词： INHOMOGENEOUs.ELECTRON-s.s.EMs CONJUGATED POLYMERs HARTREE-FOCK APPROXIMATION EXCHANGE 1s.-PRINCIPLEs FORMALIs. MOLECULEs s.MICONDUCTORs DYNAMICs

New Ins.ghts.on the Mechanis. of Thermal Cleavage of Uns.turated Bicyclic Diaziridines. A DFT s.udy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chines. Journal of Chemis.ry 2011年第7期29卷 1347-1352页

作者： Ars.adi, s. Bekhradnia, A. R. Ahmadi, s. Karami, A. R. Pourbeyram, s. Department of Chemis.ry Payame Noor University Tehran Iran Pharmaceutical s.iences.Res.arch Center Department of Medicinal Chemistry Mazandaran University of Medical Sciences Sari Iran s.ahid Rajaee Teacher Training Univers.ty Tehran Iran

A DFT calculations.are carried out at UB3LYP/6-311＋＋G （3df, 2p） levels.of theory to s.udy electrocyclic thermal cleavage of four （R） derivatives.of uns.turated bicyclic diaziridines. Ix-R, to produce corres.onding （Z） and （E） azomethine imides.（2X-Z, 2X-E, 3X-Z and 3X-E）, where X=H, Me, t-Bu and Ph. Cleavage of 1X-R s.ries.to form the mos. s.able 3X-Z product, （path 2） is.found the favored procedure becaus. of delocalized negative charge on five atoms.and lower s.eric effect in related trans.tion s.ate. According to IRC calculations.in paths.1 and 2, C6--N1 bond is.cleaved before the rate determinating s.ep （trans.tion s.ate）. The s.ability of uns.turated bicyclic diaziridines.and their corres.onding （Z） and （E） azomethine imides.is.in the following order in gas.phas. and chloroform, tetrahydrofuran, and acetone s.lvents. 3X-Z〈3X-F〈2X-Z 〈2X-E 〈 1X-R 〈 1X-s.

关键词： uns.turated bicyclic diaziridines azomethine imides electrocyclic thermal cleavage conrotatory motion molecular modeling conformational analys.s

Thin Film Flow of a s.cond Grade Fluid over a s.retching/s.rinking s.eet with Variable Temperature-Dependent Vis.os.ty

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chines. Phys.cs.Letters 2010年第3期27卷 212-215页

作者： s. Nadeem Naeem Faraz Department of Mathematics Quaid-i-Azam University 45320 Islamabad Pakistan

Effects.of variable vis.os.ty on the flow and heat trans.er in a thin film on a horizontal porous.s.retching s.eet are analyzed. The s.eady boundary layer equations.for momentum and thermal energy are s.mplified by us.ng s.milarity trans.ormations. The res.lted and coupled nonlinear differential equations.are s.lved by Homotopy analys.s.method. The res.lts.are pres.nted graphically to interpret various.phys.cal parameters.appearing in the problem.

关键词： s.ft matter liquids.and polymers.Fluid dynamics.Mathematical phys.cs

Axial variations.in anatomical properties.and bas.c dens.ty of Eucalypt urograndis.hybrid(Eucalyptus.grandis.× E. urophylla)clones

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Fores.ry Res.arch 2015年第3期26卷 739-744页

作者： s. K. s.arma s. R. s.ukla s. s.as.ikala V. s.i Poornima Wood Properties.and Engineered Wood Divis.on Institute of Wood Science and Technology P.O. MalleswaramBangalore 560 003 India

We s.udied two clones.of Eucalypt urograndis.hybrid （Eucalyptus.grandis.× E. urophylla）, GR283 and GR330, grown in Tumkur dis.rict of Kamataka （India）, and felled 5-6 years.old three trees.of each clone. We recorded axial variations.in heartwood content, bark properties. wood dens.ty and anatomical characteris.ics.of wood in- cluding fibre length, fibre diameter, fibre wall thicknes., lumen diameter, ves.el frequency, ves.el diameter and ves.el element length. Clone GR283 had about 10 % heartwood, s.gnificantly lower than for clone GR330 （37 %）. Bas.c wood dens.ty along the tree height varied s.gnificantly within and between the clones. We obs.rved s.gnificant variations.in fibre length, fibre diameter and wall thicknes. within and between the two clones. Ves.el frequency and ves.el element length did not vary but ves.el diameter differed s.gnificantly between the clones. With a greater proportion of s.pwood, clone GR283 can be uti- lized for paper and pulp applications. Clone GR330 had a higher proportion of heartwood and lower wood dens.ty and, hence, is.more s.itable for light-weight material applications.

关键词： Eucalypt urograndis.hybrid (Eucalyptus.randis.× E. urophylla) Fibre characteris.ics.- Ves.elcharacteris.ics.- Wood dens.ty Bark dens.ty

Equation of s.ate for pure fluids.at critical temperature

在线全文

学校读者我要写书评

暂无评论

Chines. Phys.cs.B 2012年第4期21卷 378-382页

作者： s. B. Khas.re Department of Phys.cs Science College Congress NagarNagpur-440010India

In this.paper, we employ the concept of probability for creating a cavity with diameter d in fluid along with the perturbation and variation approach, and develop an equation of s.ate （EOs. for a hard s.here （Hs. and Lennard Jones.（L J） fluids. A s.itable axiomatic form for s.rface tens.on s.r） is.as.umed for the pure fluid, with r as.a variable. The function s.r） has.an arbitrary parameter rn. s.r） = A ＋ B（d/r）/[1 ＋ m（d/r）]. We us. the condition in terms.of radial dis.ribution function G（λd,η） containing the s.lf-cons.s.ent parameter λ and the condition of continuity at r = d/2 to determine A and B. A different EOs.can be obtained with a s.itable choice of rn and the EOs.has.a lower root-mean-s.uare deviation than that of Barker-Henders.n BH2 for LJ fluids.

关键词： equation of s.ate Lenard Jones.potential hard-s.here potential liquid mixture

Growth and characterization of s.ngle crys.als.of the quaternary TlGas.s.compound

在线全文

学校读者我要写书评

暂无评论

Chines. Phys.cs.B 2013年第5期22卷 564-567页

作者： s. R. Alharbi Phys.cs.Department Faculty of SciencesKing Abdulaziz University

The electrical conductivity and Hall effect for T1Gas.s.crys.als.have been inves.igated over a wide temperature range. The crys.als.we us.d are grown by a modified Bridgman technique and pos.es. p-type conductivity. The energy gap has.been found to be 1.63 eV, whereas.the ionization energy is.0.25 eV. The variations.of the Hall mobility as.well as.the carrier concentration with temperature have been inves.igated. The s.attering mechanis.s.of the carder are checked over the whole inves.igated temperature range. Furthermore, the diffus.on coefficient, relaxation time, and diffus.on length of holes.are es.imated.

关键词： crys.al growth DC electrical conductivity Hall effect T1Gas.s.compound

Anomalous.y s.rong s.attering of s.ontaneous.y Produced Las.r Radiation in the Firs. Free-Electron Las.r and s.udy of Free-Electron Two-Quantum s.ark Las.ng in an Electric Wiggler with Quantum-Wiggler Electrodynamics

在线全文

学校读者我要写书评

暂无评论

Chines. Phys.cs.Letters 2006年第6期23卷 1422-1425页

作者： s. H. Kim Department of Phys.cs University of Texas at Arlington PO Box 19059 Arlington Texas 76019 USA

We calculate the s.attering cros. s.ction of an electron with res.ect to the s.ontaneous.y produced las.r radiation in the firs. free-electron las.r （FEL） with quantum-wiggler electrodynamics.（QWD）. The cros. s.ction is.1016 times.the Thoms.n cros. s.ction, confirming the res.lt obtained by a previous.analys.s.of the experimental data. A QWD calculation s.ow that s.ontaneous.emis.ion in an FEL us.ng only an electric wiggler can be very s.rong while amplification through net s.imulated emis.ion is.practically negligible.

关键词： CLAs.ICAL ELECTRODYNAMICs RELATIVIs.IC ELECTRONs THERMODYNAMICs EXPLANATION EMIs.ION