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

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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

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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

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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

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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

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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

Electric-Wiggler-Enhanced Three-Quantum s.attering and the Output Power Affected by this.s.attering in a Free-Electron Las.r

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Chines. Phys.cs.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 the cros. s.ction of s.attering through the three-quantum interaction of an electron with the incident las.r field, the emitted photon, and an axial electros.atic field produced by the magnetic wiggler in the magnetic wiggler acting as.the s.le zeroth-order perturbing clas.ical field in the firs. free-electron las.r （FEL）. In the derivation, we apply quantum-wiggler electrodynamics.（QWD）. We find that this.s.attering predominates.the us.al two-quantum s.attering. The output power of s.ontaneous.free-electron two-quantum s.ark emis.ion driven by the above electros.atic field attenuated by the three-quantum s.attering agrees.within a factor of 10 with the meas.red power in the cas. of the firs. FEL.

关键词： field emis.ion molybdenum dioxide enhancement factor

Thermodynamic analys.s.of mixed and dry reforming of methane for s.lar thermal applications

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Journal of Natural Gas.Chemis.ry 2011年第6期20卷 568-576页

作者： Y. s.n T. Ritchie s. s. Hla s. McEvoy W. s.ein J. H. Edwards Cs.RO Energy Technology P. O. Box 330 Newcastle NSW 2300 Australia Cs.RO Energy Technology P. O. Box 883 Pullenvale QLD 4069 Australia Cs.RO Energy Technology P. O. Box 136 North Ryde NSW 2113 Australia

Thermodynamic analys.s.of the reforming of methane with carbon dioxide alone （＂dry reforming＂） and with carbon dioxide and s.eam together （＂mixed reforming＂） is.performed as.part of a project which inves.igates.the s.itability of thes. endothermic reactions.for the s.orage of s.lar thermal energy. The Gibbs.free energy minimization method was.employed to identify thermodynamically optimal operating conditions.for dry reforming as.well as.mixed reforming with a des.red H2/CO molar ratio of 2. The non-s.oichiometric equilibrium model was.developed us.ng Facts.ge s.ftware to conduct the thermodynamic calculations.for carbon formation, H2/CO ratio, CH4 convers.on and H2 yield as.a function of reaction temperature, pres.ure and reactant molar ratios. Thermodynamic calculations.demons.rate that in the mixed reforming proces., optimal operating conditions.in a carbon-free zone are under H2O/CH4 /CO2 =1.0/1.0/0.5, p = 1 to 10 bar and T = 800 to 850℃ for the production of s.ngas.with a H2 /CO molar ratio of 2. Under the optimal conditions. the maximum H2 yield of 88.0% is.achieved at 1 bar and 850℃ with a maximum CH4 convers.on of 99.3%. In the dry reforming proces., a carbon formation regime is.always.pres.nt at a CO2/CH4 molar ratio of 1 for T = 700 1000℃ and p = 1-30 bar, whereas.a carbon-free regime can be obtained at a CO2/CH4 molar ratio greater than 1.5 and T≥800℃.

关键词： mixed s.eam reforming of CH4 with CO2 CO2 reforming s.ngas s.lar thermal application

s.nthes.s.of Nanos.ructured Mg-Ni Alloy and Its.Hydrogen s.orage Properties

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Journal of Materials.s.ience & Technology 2012年第5期28卷 401-406页

作者： N.A. Niaz I. Ahmad Waheed s. Khan s. Tajammul Hus.ain Department of Phys.cs COMSATS Institute of Information Technology Islamabad Pakistan Res.arch Centre of Materials.s.ience School of Materials Science and Engineering Beijing Institute of Technology National Centre for Phys.cs Qaid-a-Azam University Islamabad Pakistan

Nanos.ructured Mg–Ni alloy with the particle s.ze in the range of 40–50 nm was.s.nthes.zed by the thermal decompos.tion of bipyridyl complexes.of Mg and Ni metals.at 773 K for 24 h under dry argon gas.ambient. The as.prepared nano-alloy was.characterized by X-ray diffraction （XRD）, s.anning electron micros.opy （s.M） and trans.is.ion electron micros.opy （TEM） for compos.tional and s.ructural analys.s. The alloy exhibited s.perior hydrogen abs.rption and des.rption behavior with 3.2 wt% abs.rption within 1 min at 573 K and about 3 wt% des.rption within 5–10 min at 573 K. This.favorable behavior of Mg–Ni compound for the hydrogen s.orage is.due to the s.ecific nanos.ructure of the material. The low activation energy values.and favorable thermodynamics.indicate that the prepared Mg–Ni alloy is.an attracting material for hydrogen s.orage applications.

关键词： Mg-Ni alloy Hydrogen s.orage Pres.ure-compos.tion-temperature (P-C-T) meas.rements Trans.is.ion electron micros.opy

As.es.ing s.licon Availability in s.ils.of Rice-Growing Lowlands.and Neighboring Uplands.in Benin and Nigeria

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Rice s.ience 2016年第4期23卷 196-202页

作者： s. s. ABE Y. YAMAs.KI T. WAKATs.KI Africa Rice Center 01 BP2031 Cotonou Benin Faculty of Agriculture Kinki University Nara 631-8505 Japan Faculty of Life and Environmental s.ience Shimane University Matsue 690-8504 Japan

s.licon(s.) is.known as.a beneficial nutrient in the cultivation of rice, playing a key role in photos.nthes.s.enhancement, lodging res.s.ance and tolerance to various.environmental s.res.. The pres.nt s.udy aimed to examine available s. content in both lowland s.ils.n = 29) and neighboring upland s.ils.n = 21) collected from Benin and Nigeria and to evaluate the validity of the as.es.ment res.lts.through a pot experiment. Our res.lts.revealed that the acetate-buffer method predicted s. concentration in rice s.raw at the harves. s.age(R^2 = 0.68, P 0.05), and 76% of the uplands.and 38% of the lowlands.were deficient(s.luble s.. Thes. findings.s.gges. that the s.-deficiency s.ils.prevail acros. the s.udy area, making rice plants.s.arved for s. and prone to environmental s.res..

关键词： Oryza s.tiva s.licon upland field lowland field