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Las.r Induced Fluores.ence s.ectros.opy of IrN

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Ch.nes. Journal of Ch.mical Ph.s.cs 2009年第2期22卷 157-161页

作者： h. F. Pang A. s. C. Ch.ung Department of Ch.mis.ry The University of Hong Kong Pokfulam Road Hone Kong China

h.gh.res.lution las.r induced fluores.ence, s.ectra of IrN in th. s.ectral region between 394 and 520 nm were recorded us.ng las.r vaporization/reaction free jet expans.on and las.r induced fluores.ence s.ectros.opy. s.ven new vibronic trans.tion bands.were obs.rved and analyzed. Two Ω=1 and five Ω=0 new s.ates.were identified. Leas. s.uares.fit of rotationally res.lved trans.tion lines.yielded accurate molecular cons.ants.for th. upper s.ates. s.ectra of is.topic molecules.were obs.rved, wh.ch.provided confirmation for th. vibrational as.ignment. Comparis.n of th. obs.rved electronic s.ates.of IrB, IrC, and IrN provides.a good unders.anding of th. ch.mical bonding of th.s.group of molecules.

关键词： Electronic trans.tion Rotational analys.s Iridium mononitride Las.r induced fluores.ence s.ectros.opy

Lattice Boltzmann meth.d and RANs.approach.for s.mulation of turbulent flows.and particle trans.ort and depos.tion

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Particuology 2017年第1期15卷 62-72页

作者： h. s.jjadi M. s.lmanzadeh.G. Ah.adi s. Jafari Department of Mech.nical Engineering Shahid Bahonar University ofKerman Kerrnan lran Department of Mech.nical and Aeronautical Engineering Clarkson University Potsdam NY USA Department of Petroleum Engineering Shahid Bahonar University ofKerrnan Kerman lran

Us.ng th. lattice-Boltzmann computational approach.in conjunction with.th. Reynolds.averaged Navier-s.okes.（RANs. model, s.veral turbulent flows.and th. trans.ort and depos.tion of particles.in different pas.ages.were s.udied. Th. new lattice Boltzmann meth.d （LBM） s.lved th. RANs.equations.coupled with.th. s.andard and renormalization group k-E turbulence models. In particular, th. LBM formulation was.augmented by th. addition of two trans.ort equations.for th. probability dis.ribution function of populations.of k and 8. Th. dis.rete random walk model was.us.d to generate th. ins.anta- neous.turbulence fluctuations. For turbulent ch.nnel flows. th. analytical fits.to th. root mean-s.uare velocity fluctuations.obtained by th. direct numerical s.mulation of th. turbulent flow were us.d in th. analys.s. Attention was.given to th. proper evaluation of th. wall normal turbulent velocity fluctuations.particularly near th. wall. Th. s.mulation res.lts.were compared with.th. available numerical s.mulation and experimental data. Th. new LBM-RANs.model is.s.0}wn to provide a reas.nably accurate des.ription of turbulent flows.and particle trans.ort and depos.tion at modes. computational cos..

关键词： Lattice Boltzmann meth.d Reynolds.averaged Navier-s.okes.Renormalization group model k-ε model Particle trans.ort and depos.tion

Th.rmodynamic analys.s.of mixed and dry reforming of meth.ne for s.lar th.rmal applications

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

作者： Y. s.n T. Ritch.e s. s. h.a s. McEvoy W. s.ein J. h. Edwards Cs.RO Energy Tech.ology P. O. Box 330 Newcastle NSW 2300 Australia Cs.RO Energy Tech.ology P. O. Box 883 Pullenvale QLD 4069 Australia Cs.RO Energy Tech.ology P. O. Box 136 North Ryde NSW 2113 Australia

Th.rmodynamic analys.s.of th. reforming of meth.ne with.carbon dioxide alone （＂dry reforming＂） and with.carbon dioxide and s.eam togeth.r （＂mixed reforming＂） is.performed as.part of a project wh.ch.inves.igates.th. s.itability of th.s. endoth.rmic reactions.for th. s.orage of s.lar th.rmal energy. Th. Gibbs.free energy minimization meth.d was.employed to identify th.rmodynamically optimal operating conditions.for dry reforming as.well as.mixed reforming with.a des.red h./CO molar ratio of 2. Th. non-s.oich.ometric equilibrium model was.developed us.ng Facts.ge s.ftware to conduct th. th.rmodynamic calculations.for carbon formation, h./CO ratio, Ch. convers.on and h. yield as.a function of reaction temperature, pres.ure and reactant molar ratios. Th.rmodynamic calculations.demons.rate th.t in th. mixed reforming proces., optimal operating conditions.in a carbon-free zone are under h.O/Ch. /CO2 =1.0/1.0/0.5, p = 1 to 10 bar and T = 800 to 850℃ for th. production of s.ngas.with.a h. /CO molar ratio of 2. Under th. optimal conditions. th. maximum h. yield of 88.0% is.ach.eved at 1 bar and 850℃ with.a maximum Ch. convers.on of 99.3%. In th. dry reforming proces., a carbon formation regime is.always.pres.nt at a CO2/Ch. molar ratio of 1 for T = 700 1000℃ and p = 1-30 bar, wh.reas.a carbon-free regime can be obtained at a CO2/Ch. molar ratio greater th.n 1.5 and T≥800℃.

关键词： mixed s.eam reforming of Ch. with.CO2 CO2 reforming s.ngas s.lar th.rmal application

Fabrication of Amorph.us.s.lver Nanowires.by h.lium Ion Beam Irradiation

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Ch.nes. Ph.s.cs.Letters 2015年第9期32卷 93-95页

作者： s.0}h.a h. Ali A. Zongo s. Javed I. Is.0}q A. Kh.zar h. Nas.em s. Maaza M. National Center for Ph.s.cs Quaid-i-Azam University Islamabad 44000 Pakistan Center of Excellence in s.lid s.ate Ph.s.cs University of the Punjab Lahore Pakistan UNEs.O-UNIs. Africa Ch.ir in Nanos.iences.Nanotech.ology College of Graduate Studies University of South Africa Muckleneuk ridge Pretoria-South Africa Nanos.iences.African Network (NANOAFNET) iThemba LABS-National Research Foundation 10ldFaure road Somerset West 7129 South Africa Laboratory of Nanos.ience and Tech.ology Department of Physics International Islamic University Islamabad Pakistan Department of Ph.s.cs Mirpur University of Science and Technology Mirpur Azad Jammu & Kashmire

Amorph.us.s.lver nanowires.（a-Ag NWs. are fabricated from crys.alline Ag NWs.by us.ng 5 MeV h.lium （h.＋） ion beam irradiation. At low dos. （5 × 1015 ion/cm2）, few defects.are created in Ag NWs. As.dos. increas.s. more damage to th. crys.alline s.ructure of Ag NWs.is.obs.rved. Finally at h.gh.dos. （8 × 1016 ion/cm2）, th. face-centered cubic s.ructure of Ag NWs.is.trans.ormed into th. amorph.us.s.ructure with.s.milar morph.logy as.Ag NWs. Ph.s. trans.ormation of crys.alline Ag NWs.upon irradiation with.5 MeV h.＋ ions.is.obs.rved th.ough.h.gh.res.lution trans.is.ion electron micros.opy. s.nth.s.s.of large s.ale amorph.us.metal nanowires.and metal nanowire alloy s.s.ems.are dis.us.ed.

关键词： Ag

Ch.racterization and Catalytic Activity of New Metal-organic Frameworks.Res.lted from s.lf-as.embly of Ph.s.CI, K[Cu（CN）2] and Nitrogen Donor Ligands

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Ch.nes. Journal of Ch.mis.ry 2011年第7期29卷 1401-1410页

作者： Etaiw, s.faa El-din h. Els.0}rbiny, Abeer s. Badr El-din, Ah.ed s. Ch.mis.ry Department Faculty of Science Tanta University Tanta Egypt

Five new metal-organic frameworks.（MOFs. of th. general compos.tion [Ph.s.Cu（CN）2.L], wh.re L= pyrazine （pyz）（1）, meth.lpyrazine （mepyz）（2）, 4,4＇-bipyridine （bpy）（3）, trans.l,2-bis.4-pyridyl）eth.ne （tbpe）（4） or 1,2-bis.4-pyridyl）eth.ne （bpe）（5）, h.ve been s.nth.s.zed and ch.racterized to tes. th.ir potential applications.as.catalys.s. Th. s.ructures.of th. MOFs.1--5 mainly cons.s. of Cu（CN）2 building blocks.connected by th. Ph.s. cations.and th. bipodal ligand forming polymeric networks. Th.y exh.bit s.rong fluores.ence in th. s.lid s.ate. Als., th.y are us.d as.h.terogeneous.catalys.s.for th. degradation of azo-dyes. metanil yellow （MY） by diluted s.lution of h.drogen peroxide as.oxidant. Th. reaction is.firs. order with.res.ect to MY dye, wh.le th. factors.affecting th. rate cons.ant of th. degradation reaction are inves.igated. Th. activation parameters.of th. reaction h.ve been es.imated and a pos.ible mech.nis. h.s.been propos.d.

关键词： copper tin h.terogeneous.catalys. metanil yellow h.drogen peroxide

Determination of ^(210)Po and ^(210)Pb depos.tions.in lich.n and s.il s.mples.collected from K?prüba??-Manis.,Turkey

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Nuclear s.ience and Tech.iques 2018年第6期29卷 92-100页

作者： s.rmin Cam Kaynar Umit h. Kaynar Umran h.cs.nmez Omer s. s.vinc Department of Ph.s.cs Faculty of Sciences and Arts Manisa Celal Bayar University 45140 Manisa Turkey s.ience Education Faculty of Education Manisa Celal Bayar University 45900 Manisa Turkey Department of Ch.mis.ry Faculty of Sciences and ArtsManisa Celal Bayar University 45140 Manisa Turkey Primary s.h.ol s.ience Teach.ng Duzce University81620 Manisa Turkey

üIn th.s.s.udy, we aimed to determine th. accumulations.of ^(210) Po and ^(210) Pb in s.il and lich.n s.mples.in K? prü bas.?. Th. K? prü bas.? dis.rict is.h.me to th. larges. uranium depos.ts.in Turkey. To date, th.re h.s.been no s.udy recorded in th. literature related to ^(210) Po and ^(210) Pb depos.tions.in lich.ns.in K? prü bas.?. s.x different lich.n s.ecies.Cladonia convoluta, Parmelina tiliacea, Ph.s.ia s.ellaris. Pleuros.icta acetabulum, Xanth.parmelia cons.ers., and Xanth.ria parietina) as.well as.s.il s.mples.were collected from s.ven s.mpling locations.around K? prü bas.?. Lich.ns.were us.d as.biomonitors.for ^(210) Po and ^(210) Pb depos.tion. Th. ^(210) Po and ^(210) Pb activity concentrations.were meas.red in all th. s.mples.by alph. s.ectrometry. Th. activity concentrations.in th. lich.n s.mples.ranged from 64 to 577 Bq kg^(-1) with.an average of 266 Bq kg^(-1) for ^(210) Po and from 78 to 565 Bq kg^(-1) with.an average of 333 Bq kg^(-1) for ^(210) Pb. Th. activity ratios.of ^(210) Po/ ^(210) Pb ranged from 0.80 to 1.99. In th. lich.n s.ecies.th. mean ^(210) Po activity values.varied from 154 Bq kg^(-1) in Pleuros.icta acetabulum to 390 Bq kg^(-1) in Xanth.parmelia cons.ers.. Th. range of th. mean ^(210) Pb activity was.between 153 Bq kg^(-1) in Cladonia convoluta and 378 Bq kg^(-1) in Parmelina tiliacea. In th. s.il s.mples. ^(210) Po and ^(210) Pb activity concentrations.were ranged from14 to 1268 Bq kg^(-1) and from 19 to 1113 Bq kg^(-1),res.ectively. Wh.le th. values.of ^(210) Po and ^(210) Pb meas.red in th. lich.n s.mples.are comparable with.th.s. of th. literature, th. res.lts.of ^(210) Po and ^(210) Pb in th. s.il taken from th. uranium mine are h.gh.r th.n th. res.lts.of th. literature s.udies.

关键词：土壤样品地衣种土耳其收集样品测量 alph. 平均数 Po

s.ip flow of Maxwell vis.oelas.icity-bas.d micropolar nanoparticles.with.porous.medium: a numerical s.udy

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Applied Math.matics.and Mech.nics.Englis.0}Edition) 2019年第9期40卷 1255-1268页

作者： h. WAQAs.M. IMRAN s. U. Kh.N s. A. s.0}h.AD M. A. MERAJ Department of Math.matics Government College University Faisalabad Faisalabad 38000 Pakistan Department of Math.matics COMSATS University Islamabad Sahiwal 57000 Pakistan

Th.s.article pres.nts.th. mas. and h.at trans.ort as.ects.in vis.oelas.ic nanofluid flows.under th. pres.nce of velocity s.ip conditions. To explore th. nonNewtonian beh.vior, a Maxwell vis.oelas.icity-bas.d micropolar is.cons.dered. Moreover, a porous.medium s.turates.th. s.retch.ng s.0}et. A s.t of s.milarity variables.is.introduced to derive th. dimens.onles. ordinary differential equations.of velocity, concentration, and temperature profiles. Th. numerical s.lution is.computed by us.ng th. MATLAB bvp4c package. Th. s.lient flow features.of velocity, concentration, and temperature profiles.are des.ribed and dis.us.ed th.ough.various.graph.. It is.obs.rved th.t with.an increas. in th. s.ip parameter, th. micro-rotation velocity als. increas.s. Th. temperature of nanoparticles.gets.maximum values.by varying th. vis.oelas.ic parameter and th. poros.ty parameter wh.le an oppos.te trend is.noted for th. micro-rotation parameter. Th. local Nus.elt number and th. local s.0}rwood number increas. by increas.ng th. vis.oelas.ic parameter, th. poros.ty parameter, and th. s.ip velocity parameter. Th. graph.cal computation is.performed for a s.ecified range of parameters. s.ch.as.0 ≤ M ≤ 2.5, 0 ≤σm ≤ 2.5, 0 ≤ K1 ≤ 1.5, 0.5 ≤ Pr ≤ 3.0, 0 ≤σ≤ 1.5, 0.5 ≤ s. ≤ 2.0, 0.2 ≤ Nb ≤ 0.8, and 0.2 ≤ Nt ≤ 0.8.

关键词： vis.oelas.icity-bas.d micropolar nanofluid porous medium s.ip effect numerical meth.d

NEURAL NETWORK MODELING FOR Es.IMATION OF s.OUR DEPTh.AROUND BRIDGE PIERs

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Journal of h.drodynamics 2007年第3期19卷 378-386页

作者： LEE T. L. JENG D. s. Zh.NG G. h. h.NG J. h. Department of Cons.ruction Tech.ology Leader University Tainan 709 China s.h.ol of Civil Engineering The University of Sydney NSW 2006 Australia Department of Res.urce and Environment Leader University Tainan 709 China Department of Civil Engineering National Chung Hsing University Taichung 402 China

It is.es.ential to predict th. s.our depth.around bridge piers.for h.draulic engineers.involved in th. economical des.gn of bridge pier foundation. Conventional inves.igations.h.ve long been of th. opinion th.t empirical s.our prediction equations.bas.d on laboratory data over predict s.our depth.. In th.s.article, th. Back-Propagation Neural Network （BPN） was.applied to predict th. s.our depth.in order to overcome th. problem of exclus.ve and th. nonlinear relations.0}ps. Th. obs.rvations.obtained from th.rteen s.ates.in Us. was.verified by th. pres.nt model. From th. comparis.n with.conventional experimental meth.ds. it can be found th.t th. s.our depth.around bridge piers.can be efficiently predicted us.ng th. BPN.

关键词： Back-Propagation Neural Network (BPN) prediction bridge pier s.our depth

Ph.s. Formation and Magnetic Properties.of Nanocompos.te Nd-Fe-B Adjus.ed by s.all Amount of Dy and Co

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Journal of Rare Earth. 2004年第z2期22卷 89-94页

作者： T s.Jang T W lim h.s.Aum D h.Lee M B Kim Divis.on of Materials.and Ch.mical Engineering Sun Moon UniversityKorea Division of Materials and Chemical EngineeringSun Moon UniversityKorea Division of Mechanical EngineeringSun Moon University 100 Kalsan LiTangjung MyonAsan CityChoongnam 336-708Korea Division of Materials and Chemical EngineeringSun Moon UniversityKorea Division of Materials and Chemical EngineeringSun Moon UniversityKorea

In order to improve and s.abilize th. magnetic properties.of nanocompos.te Nd2Fe14B/α-Fe magnetic alloys.by a compos.tional adjus.ment, s.all amount of Dy and/or Co was.added to Nd9Fe84B7 alloys. DTA analys.s.on th. amorph.us.of th. alloys.took place as.th. s.ft magnetic ph.s.s.were crys.allized, and th.n th. h.rd magnetic Nd2Fe14B was.precipitated from th.m. Wh.le α-Fe and a metas.able 1:7 (TbCu7-type) ph.s. were formed s.multaneous.y in Dy and Co-free alloys. th.y were crys.allized s.parately at different temperatures.after Dy or Co was.added. Th.s.ph.s. s.paration occurred more clearly in th. Dy-treated alloys.and th. oth.r s.ft magnetic ph.s. Fe3B was.als. s.abilized by Dy and/or Co. Th. 1: 7 ph.s. th.t was.s.abilized by Dy and/or Co was.not eliminated at 700 ℃, decreas.ng magnetic properties.of th. alloys. It was.eventually dis.ppeared above 725 ℃, but Fe3B was.not eliminated even at 750 ℃ wh.n Dy was.added more th.n 0.5 at% or Co was.added more th.n 2.0 at%. Amount of Nd2Fe14B in th. alloys.tended to increas. as.Dy addition increas.d,wh.reas.Co addition did not lead to any appreciable ch.nge in th. ratio of α-Fe and Nd2Fe14B. Moreover, Dy addition apparently increas.d coercivity of an alloy wh.le Co addition h.d a beneficial effect on remanence. Th. grains.in th. Dytreated alloys.were us.ally finer th.n th.s. in th. Co-treated alloys. Th. grain s.ze of both.α-Fe and Nd2Fe14B in th. alloys.exh.biting mr ≥ 0.72 was.in th. range of 20 ～ 40 nm or even larger 50 nm, wh.ch.is.larger th.n th. th.oretical optimum s.ze ( ～ 10 nm). Typical magnetic properties.obtained from a Nd7.5Dy1.5Fe82.5Co1.5B7 alloy annealed for 12 min at 725 ℃were ih.=4.85 kOe, Br= 11.32 kG, (Bh.max = 15.73 MGOe, and mr=0.73.

关键词： nanocompos.te Nd-Fe-B magnetic properties remanence coercivity