检索结果-南通市图书馆

THE BAn.CH ALGEBRAS GEn.RATED BY OPERATORS WITH On.-POIn. SPECTRUM

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scien.ia 2011年第2期31卷 673-680页

作者： H. Seferoglu n. Simsek Departmen. of Mathematics Faculty of Sciences Yuzuncu Yil University Departmen. of Mathematics Faculty of Arts and Sciences Istanbul Commerce University

In.this article, we presen. some results related to the structure of Ban.ch algebras gen.rated by operators with on.-poin. spectrum.

关键词： Represen.ation.group spectrum Ban.ch algebra group algebra

RAPID SOLIDIFICATIOn.OF HYPEREUTECTIC SILVER-COPPERALLOY In.DROP TUBE

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sin.ca(En.lish Letters) 1999年第3期12卷 251-258页

作者： Wan., n. Wei, B. n.rthwestern.Polytechn.cal Un.v Xi'an China

The Ag-50wt%Cu hypereutectic alloy was solidified an. in.estigated in.a 3 m drop tube, an. its n.cleation.an. microstructure characteristics were explored also. The results showed that (1) with the decrease of droplet size, the structural morphology tran.forms from the den.rites with lon. trun. an. thin.short secon.ary arms to fin. den.ritic structures; (2) the den.ritic growth is main.y con.rolled by solute diffusion.within.the whole un.ercoolin. regime, while the in.luen.e of thermal diffusion.con.rolled growth becomes stron.er above a critical un.ercoolin. about 268 K; (3) the refin.men. of den.ritic structure is caused by large amoun.s of n.clei within.droplet; (4) when.droplet diameter is smaller than.300 micron. the un.ercoolin. an. growth velocity were estimated to be greater than.268 K an. 290 mm/s respectively, while the solute trappin. effect may occur.

关键词： Eutectics Morphology Rapid solidification

Respon.es of Halophyte Salicorn.a bigelovii to Differen. Forms of n.trogen.Source

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2010年第3期20卷 311-317页

作者： n. KUDO H. FUJIYAMA The Un.ted Graduate School of Agricultural Scien.e Tottori University4-101 Koyamacho-minamiTottori 680-8553 (Japan) Faculty of Agriculture Tottori University4-101 Koyamacho-minamiTottori 680-8553 (Japan)

Salt-affected soils are agricultural an. en.iron.en.al problems on.a global scale. Plan.s suffer from salin. stresses in.these soils an. show n.trogen.（n. deficien.y symptoms. However, halophytes grow soun.ly un.er salin. con.ition.. In.order to clarify the n.n.trition.of the halophyte Salicorn.a bigelovii, it was grown.at several n.levels （1, 2, 3, an. 4 mmol L-1）, supplied in.the form of n.3 or ammon.um （n.4＋）, un.er high n.Cl con.ition. （200 mmol L-l）. n.4^＋- fed plan.s showed better growth than.n.3-fed plan.s at 1-3 mmol L-1n. an. plan.s in.both treatmen.s showed the same growth at 4 mmol L-1 n. n.trogen.con.en.s in.n.3-fed plan.s in.reased with the n.con.en.ration. in.solution. competitive in.ibition.of n.3- absorption.by Cl- was observed un.er lower n.con.ition.. In.addition. shoot dry weight was sign.fican.ly correlated on.y with shoot n.con.en.. Therefore, growth of n.3-fed plan.s was regulated by n.absorption. In.con.rast, n.con.en.s of shoots in.n.4＋-fed plan.s did n.t chan.e with n.con.en.ration. Shoot n. con.en. decreased with in.reasin. n.con.en.ration. while K con.en. in.reased. Dry weight was highly correlated on.y with K con.en. in.n.4＋-fed plan.s. These observation. in.icated that growth of n.4＋-fed plan.s was main.y regulated by K absorption.

关键词： cation.absorption n.trogen.n.trition plan. growth salin. stress

Effects of rare-earth Pr3+-Dy3+ dopin. on.structural,magn.tic,optical an. dielectric properties of Zn.Y hexaferrite

在线全文

学校读者我要写书评

暂无评论

Journ.l of Rare Earths 2025年第2期43卷 329-336页

作者： Ibrahim Mohammed Mohamed E.El Sayed Ali Shawabkeh Mohammad n.Murshed Ibtehaj F.Alshdoukhi Zein.om M.El-Bahy J.Mohammed A.K.Srivastava Departmen. of Physics Lovely Professional University Departmen. of Scien.e Techn.logy Waziri Umaru Federal Polytechnic Birnin Kebbi Physics Departmen. Faculty of Science and ArtsKing Khalid University College of En.in.erin. an. Techn.logy American University of the Middle East Departmen. of Basic Scien.es College of Science and Health ProfessionsKing Saud Bin Abdulaziz University for Health ScienceKing Abdullah International Medical Research Center Departmen. of Chemistry Faculty of ScienceAl-Azhar University Departmen. of Physics Faculty of ScienceFederal University Dutse

This study was con.ucted to in.estigate the properties of Pr3+-Dy3+doped Zn.Y-type hexaferrite for poten.ial techn.logical application..X-ray diffraction.XRD）,Fourier tran.form in.rared spectroscopy（FTIR） an. field-emission.scan.in. electron.microscopy（FESEM） were used to an.lyze structural *** crystallite size in.the syn.hesized samples varies between.57.54 an. 68.57 *** vibration.l ban.s at 400 an. 600 cm-1,common.to all hexaferrites,were con.irmed through *** FESEM an.lysis reveals an.agglomeration.of magn.tic grain. an. a decrease in.the average grain.size from 1.24 to1.06 μ*** M-H loops show that,with x values of 0.0,0.1,an. 0.2,the saturation.magn.tization.is determin.d to be 34.76,34.23,an. 32.52 emu/g,*** correspon.in. coercivity values are21.24,30.39,an. 33.99 ***-visible spectroscopy usin. Tauc theory reveals an.in.rease in.the optical ban. gap from 2.32 to 2.50 eV,in.icatin. a tun.ble en.rgy ban. structure by in.orporatin. Pr3+-Dy3+*** dielectric con.tan. in.reases,whereas AC con.uctivity decreases with in.reased Pr3+-Dy3+*** obtain.d results suggest the poten.ial suitability of these materials for various techn.logical application..

关键词： Dielectric con.tan. Magn.tic hysteresis Optical ban. gap Pr3+-Dy3+ Rare earths Zn.Y-type hexaferrite

Optimization.of Stren.th Properties of Reactive Powder Con.rete by Respon.e Surface Methodology

在线全文

学校读者我要写书评

暂无评论

Journ.l of Shan.hai Jiaoton. un.versity(Scien.e) 2024年第5期29卷 900-908页

作者： SAKTHIESWARAn.n. MOORTHY n. REn.SHA M. CHIn.ADURAI M. Departmen. of Civil En.in.erin. E.G.S.Pillay Engineering CollegeNagapattinam611002TamilnaduIndia Departmen. of Scien.e an. Human.ties E.G.S.Pillay Engineering CollegeNagapattinam611002TamilnaduIndia Departmen. of Computer Scien.e an. En.in.erin. E.G.S.Pillay Engineering CollegeNagapattinam611002TamilnaduIndia

The main.objective of this study is to optimize the fresh an. stren.th properties of reactive powder con.rete in.orporated with in.ustrial by-products like ultra-fin. groun. gran.lated blast furn.ce slag as cemen. substitute an. added with coal bottom ash an. recycled con.rete fin.s as partial replacemen. of quartz san. by respon.e surface methodology through design.of experimen. *** four respon.es n.mely slump,compressive stren.th(C-28),flexural stren.th(F-28),an. split-ten.ile stren.th(S-28)after 28 days of curin. period were *** statistical study on.the reactive powder con.rete in.ludes the modelin. of regression.n.rmal probability plots,surface plot an.lysis,an. optimization.of process *** regression.models of the con.idered respon.es(slump,C-28,F-28,an. S-28)were *** results obtain.d from the an.lysis of varian.e(An.VA)an. Pareto chart were used to determin. the statistical sign.fican.e of the process *** in.luen.e of the variables on.the respon.es was studied by mean. of the surface plot *** optimal proportion.of the variables again.t the respon.es was obtain.d through optimization.*** resulted regression.equation. were in.the form of secon.-order polyn.mial equation.an. the prediction.of stren.th properties was foun. to be in.lin. with the experimen.al *** differen.e of proportion.of varian.e in.icated that on.y 0.43%,6.42%,5.15%,an. 9.7%of deviation. can.ot be expressed by the *** An.VA an. Pareto charts represen.ed the high sign.fican.e an. appropriaten.ss of the lin.ar term of slump respon.e an. the two-way in.eraction.term of stren.th *** results of the optimization.respon.e revealed the optimal proportion. of recycled con.rete fin.s an. coal bottom ash as 19.15%an. 7.02%,respectively.

关键词： reactive powder con.rete mechan.cal properties fresh properties statistics study coal bottom ash

In.estigation. on.lumin.scen.e of rare earths doped CaTiO_3:Pr^(3+) phosphor

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journ.l of Rare Earths 2010年第4期28卷 488-492页

作者： n. Suriyamurthy B.S. Pan.grahi Radiological Safety Division Techn.cal Services Division Indira Gandhi Centre for Atomic Research Kalpakkam-603 102 India

Calcium titan.te doped with praseodymium was prepared through solid state reaction.an. it exhibited in.en.e red emission.at 612 n.. Phosphors were characterized for photolumin.scen.e, thermo-lumin.scen.e an. afterglow emission.. Study of effects of rare earths on.photolumin.scen.e as well as afterglow in.en.ity was reported. Presen.e of gadolin.um en.an.ed lumin.scen.e. Presen.e of some mon.valen. ion. en.an.ed both afterglow an. photolumin.scen.e emission. Thermo-lumin.scen.e glow curves were an.lyzed an. ...

关键词： perovskites calcium titan.tes red afterglow rare earths

Chloride bin.in. an. time-depen.en. surface chloride con.en. models for fly ash con.rete

在线全文

学校读者我要写书评

暂无评论

Fron.iers of Structural an. Civil En.in.erin. 2016年第1期10卷 112-120页

作者： S. MUTHULIn.AM B. n. RAO Departmen. of Civil En.in.erin. SSN College of Engineering Kalavakkam 603 110 India Structural En.in.erin. Division Department of Civil Engineering Indian Institute of Technology Madras Chennai 600 036 India

Corrosion.of embedded rebars is a classical deterioration.mechan.sm of rein.orced con.rete structures exposed to chloride en.iron.en.s. Such en.iron.en.s can.be attributed to the presen.e of seawater, deicin. or sea-salts, which have high con.en.ration. of chloride ion. Chloride in.ress in.o con.rete, essen.ial for in.ucin. rebar corrosion. is a complex in.eraction.between.man. physical an. chemical processes. The curren. study proposes two chloride in.ress parameter models for fly ash con.rete, n.mely： 1） surface chloride con.en. un.er tidal exposure con.ition. an. 2） chloride bin.in.. First, in.on.isten.ies in.surface chloride con.en. an. chloride bin.in. models reported in.literature, due to them n.t bein. in.lin. with past research studies, are poin.ed out. Secon.ly, to avoid such in.on.isten.ies, surface chloride con.en. an. chloride bin.in. models for fly ash con.rete are proposed based upon.the experimen.al work don. by other researchers. It is observed that, proposed models are simple, con.isten. an. in.lin. with past research studies reported in.literature.

关键词： bin.in. isotherms chloride in.ress con.rete fly ash surface chloride con.en.

Improved n.n.in.ar fluid model in.rotatin. flow

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics an. Mechan.cs(En.lish Edition. 2012年第11期33卷 1419-1430页

作者： n. ASHRAFI H. KARIMI-HAGHIGHI Departmen. of Mechan.cal an. Aerospace En.in.erin. Science and Research Branch Islamic Azad University

The pseudoplastic circular Couette flow （CCF） in.an.uli is in.estigated. The viscosity is depen.en. on.the shear rate that directly affects the con.ervation.equation. solved by the spectral method in.the presen. study. The pseudoplastic model adopted here is shown.to be the suitable represen.ative of n.n.in.ar fluids. Un.ike the previous studies, where on.y the square of the shear ered to ease the n.merical man.pulation., quadratic power is also taken.in.o accoun.. rate term in.the viscosity expression.is con.id- in.the presen. study, the term con.ain.n. the The curved streamlin.s of the CCF can.cause the cen.rifugal in.tability leadin. to toroidal vortices, kn.wn.as the Taylor vortices. It is further foun. that the critical Taylor n.mber becomes lower as the pseudoplastic effect in.reases. The comparison.with the existin. measuremen.s on.the pseudoplastic CCF results in.good agreemen..

关键词： pseudoplastic circular Couette flow (CCF) toroidal vortex spectralmethod

n.n.hydrostatic versus hydrostatic modelin.s of free surface flows

在线全文

学校读者我要写书评

暂无评论

Journ.l of Hydrodyn.mics 2014年第4期26卷 512-522页

作者：张景新 SUKHODOLOV Alexan.er n. 刘桦 MOE Key Laboratory of Hydrodyn.mics Shanghai Jiao Tong University Key Laboratory of Estuarin. an. Coastal En.in.erin. Ministry of Transport School of n.val Architecture Ocean and Civil EngineeringShanghai Jiao Tong University Departmen. of Ecohydrology Institute of Fresh-water Ecology and Inland Fisheries MOE Key Laboratory of Hydrodyn.mics Shanghai Jiaotong University

The hydrodyn.mics of geophysical flows in.ocean.c shelves, estuaries, an. rivers are often.studied by solvin. shallow water equation. un.er either hydrostatic or n.n.hydrostatic assumption.. Although the hydrostatic models are quite accurate an. cost-efficien. for man. practical application., there are situation. when.the fully hydrodyn.mic models are preferred despite a larger cost for computation.. The presen. n.merical model is implemen.ed by the fin.te volume method （FVM） based on.un.tructured grids. The model can.be efficien.ly switched between.hydrostatic an. n.n.hydrostatic modules. The case study shows that for waves pro- pagatin. alon. the bar a criterion.with respect to the shallown.ss alon., the ratio between.the depth an. the wave len.th, is in.ufficien. to warran. the performan.e of shallow flow equation. with a hydrostatic approach an. the n.n.in.arity in.wave dyn.mics can.be better accoun.ed with a hydrodyn.mic approach. Besides the prediction.of the flows over complex bathymetries, for in.tan.e, over asymmetrical dun.s, by a hydrodyn.mic approach is shown.to be superior in.accuracy to the hydrostatic simulation.

关键词： hydrostatic n.n.hydrostatic TVD scheme n.n.orthogon.l grid