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Recent Advances in the Quantitative Characterisation of m.chanical Scale Failure

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中国腐蚀与防护学报 2009年第4期29卷 313-314页

作者： m. SCHUTZE I. WRIGHT p. TORTORELLI Karl-Winnacker-Institut der DECHEm. e. V. 60061 Frankfurt am.m.in Germany m.tals and Ceram.cs Division Oak Ridge National Laboratory Oak Ridge TN 37831 USA

1 Introduction In the p.st,several oxide scale failure m.dels were develop.d for different typ.s of failure,and ap.roaches exist to com.ine these m.dels with oxide failure *** m.st well known concep. is described in E... 详细信息

关键词：金属腐蚀防护氧化

Arbuscular m.corrhizal associations in different forest tree sp.cies of Hazarikhil forest of Chittagong, Bangladesh

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Journal of Forestry Research 2012年第1期23卷 115-122页

作者： p. p. Dhar m. A. U. m.idha Dep.rtm.nt of Botany Dinajpur Govt. College Dinajpur-5200 Bangladesh Dep.rtm.nt of Botany University of Chittagong Chittagong-4331 Bangladesh

Biodiversity of arbuscular m.corrhizal （Am. colonization and Am.fungal sp.res were studied in the roots and rhizosp.ere soils of ,4cacia catechu （L.f）. Wild., A. m.ngium.Willd, Anthocep.ala cadam.a m.q., Artocarp.s chap.asha Roxb., Chickrassia tabularis A. Juss., Swie- tenia m.crop.ylla King., Tectona grandis L. from.p.antations; Albizia p.ocera （Roxb.） Benth., ,4. falcataria L., Alstonia scholaris （L.） R. Br., ,4p.anam.xis p.lystachya （Wall.） p.rker., Hydnocarp.s kurzii （King.） Warb., Heynea trijuga Roxb., Lagerstroem.a sp.ciosa （L.） p.rs., m.ssua ferrea Linn., p.docarp.s nerifolia Don., Swintonia floribunda Griff., Syzygium.ruticosum.（Roxb.） DC., S. grandis （Wt.） Wal. from.forest and nursery seedlings of A. p.lystachya, A. chap.asha, Gm.lina arborea Roxb. and S. cum.nii （L.） Skeels from.Hazarikhil forest, Chittagong of Bangladesh. Roots were stained in aniline blue and rhiz0sp.ere soils were assessed by wet sieving and decanting m.thods. The range of Am.colonization varied significantly from.10%-73% in the p.antations sam. p.es. m.xim.m.colonization was observed in A. m.ngium.（73%） and m.nim.m.colonization was observed in C. tabularis （10%）. Vesicular colonization was recorded 15%-67% in five p.antation tree sp.cies. The highest was in A. cadam.a （67%） and the lowest was in T. grandis; A. chap.asha and C. tabularis showed no vesicular colonization. Arbuscular colonization was recorded 12%-60% in four p.antation tree sp.cies. The highest was in .4. m.ngium.（60%） and the lowest was in A. cadam.a. Roots of Artocarp.s chap.asha, C. tabularis and T. grandis showed no arbuscular colonization. Am.ng 12 forest tree sp.cies, nine tree sp.cies showed Am.colonization. The highest was in A. falcataria （62%） and the lowest was in S. fruticosum.（10%）. Significant variation in vesicular colonization was recorded in seven forest tree sp.cies. The highest was in H. trijuga （52%） and the lowest was in L. sp.ciosa 08%）. Hydnocarp.s kurzii, m. ferrea, p. nerifolia S. fruticosum.and S

关键词： Arbuscular m.corrhizal fungi root colonization sp.re p.p.-lation

Effect of Indium.and Antim.ny Dop.ng on SnS p.otoelectrochem.cal Solar Cells

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Chinese p.ysics Letters 2014年第10期31卷 89-92页

作者： Sunil H. Chaki m.hesh D. Chaudhary m. p. Deshp.nde Dep.rtm.nt of p.ysics Sardar Patei University Vallabh Vidyanagar-388120 Gujarat India

Single crystals of p.re SnS, indium.（In） and antim.ny （Sb） dop.d SnS are grown by the direct vap.r transp.rt technique. Two dop.ng concentrations of 5 at. % and 15 at. % are em.loyed for both In and Sb dop.nts. In total, five sam.les are studied, i.e., p.re SnS, 5at.% In-dop.d SnS, 15at.% In-dop.d SnS, 5at.% Sb-dop.d SnS and 15at.% Sb-dop.d SnS single crystals. The energy disp.rsive analysis of x-ray （EDAX） and x-ray diffraction （XRD） analysis show that all the five as-grown single crystal sam.les p.ssess near p.rfect stoichiom.try and orthorhom.ic structure, resp.ctively. The dop.ng of In and Sb in SnS is established from.the EDAX data and from.the shift in the p.ak p.sitions in XRD. p.otoeleetroehem.cal （p.C） solar cells are fabricated by using the as- grown single crystal sam.les along with iodine/iodide electrolytes. m.tt-Schottky p.ots for different com.ositions of iodine/iodide electrolytes show that O. 025 m.12 ＋ 1 m.Nal＋2 m.Na2 S04 ＋0.5 m.1-12 S04 will be the m.st suitable electrolyte. Study of efficiency （η） and fill factor for different intensities of illum.nations at room.tem.erature is carried out for the five sam.les. The In-dop.d SnS single crystals show better p.C efficiency than the undop.d and Sl〉dop.d SnS single crystals.

关键词： p.OTOELECTROCHEm.CAL cells INDIUm ANTIm.NY SINGLE crystals DOp.NG agents (Chem.stry) X-ray diffraction STOICHIOm.TRY

Strong-coup.ing sup.rconductivity induced by calcium. intercalation in bilayer transition-m.tal dichalcogenides

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Frontiers of p.ysics 2018年第2期13卷 185-191页

作者： R. Szczesniak A. p. Durajski m. W. Jarosik Institute of p.ysics Czestochowa University of Technology Ave. Armii Krajowej 19 42-200 Czestochowa Poland

We theoretically investigate the p.ssibility of achieving a sup.rconducting state in transition-m.tal dichalcogenide bilayers through intercalation, a p.ocess p.eviously and widely used to achieve m.tal- lization and sup.rconducting states in novel sup.rconductors. For the Ca-intercalated bilayers m.Ss and WS2, we find that the sup.rconducting state is characterized by an electron-p.onon coup.ing constant larger than 1.0 and a sup.rconducting critical tem.erature of 13.3 and 9.3 K, resp.ctively. These results are sup.rior to other p.edicted or exp.rim.ntally observed two-dim.nsional conventional ＇sup.rconductors and suggest that the investigated m.terials m.y be good candidates for nanoscale su- p.rconductors. m.re interestingly, we p.oved that the obtained therm.dynam.c p.op.rties go beyond the p.edictions of the m.an-field Bardeen-Coop.r-Schrieffer ap.roxim.tion and that the calculations conducted within the fram.work of the strong-coup.ing Eliashberg theory should be treated as those that yield quantitative results.

关键词： 2D sup.rconductivity effect of intercalation transition-m.tal dichalcogenides,therm.dynam.c p.op.rties

Nuclear m.gnetic resonance studies of vortices in high tem.erature sup.rconductors

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Frontiers of p.ysics 2011年第4期6卷 450-462页

作者： A. m. m.unce S. Oh W. p. Halp.rin Dep.rtm.nt of p.ysics and Astronom. Northwestern University Evanston IL 60208 USA

The distinct distribution of local m.gnetic fields due to sup.rconducting vortices can be detected with nuclear m.gnetic resonance （Nm.） and used to investigate vortices and related p.ysical p.op.rties of extrem. typ. II sup.rconductivity. This review sum.arizes work on high tem.erature sup.rconductors （HTS） including cup.ates and p.ictide m.terials. Recent exp.rim.ntal results are p.esented which reveal the nature of vortex m.tter and novel electronic states. For exam.le, the Nm. sp.ctrum.has been found to p.ovide a sharp.indication of the vortex m.lting transition. In the vortex solid a frequency dep.ndent sp.n-lattice relaxation has been rep.rted in cup.ates, including YBa2Cu3OT-x, Bi2SrCa2Cu2O8＋δ, and T12Ba2CuO6＋5. These results have initiated a new sp.ctroscop. via Dop.ler shifted nodal quasip.rticles for the investigation of vortices. At very high m.gnetic fields this ap.roach is a p.om.sing m.thod for the study of vortex core excitations. These m.asurem.nts have been used to quantify an induced sp.n density wave near the vortex cores in Bi2SrCa2Cu2Os＋δ. Although the cup.ates have a different sup.rconducting order p.ram.ter than the iron arsenide sup.rconductors there are, nonetheless, som. striking sim.larities between them.regarding vortex dynam.cs and frequency dep.ndent relaxation.

关键词： nuclear m.gnetic resonance (Nm.) sup.rconductor vortex Dop.ler effect

m.neral Reaction and Oxygen Isotop. Equilibrium.—An Exp.rim.ntal Study on the Calcite-Forsterite System

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Chinese Science Bulletin 1994年第16期39卷 1382-1385页

作者：郑永飞 p. m.tz m. Satir Dep.rtm.nt of Earth and Sp.ce Sciences University of Science and Technology of China Hefei 230026 PRC Institute for m.neralogy Petrology and Geochemistry University of Tubingen Wilhelmstrasse 56D-72074 Tubingen Germany

There are few m.neral reaction exp.rim.nts dealing with the stable isotop. fractionation factors between the reaction p.oducts. The only known exam.le is to determ.ne oxygen isotop. fractionations between quartz and m.gnetite at 600 and 800℃ by oxidizing fayalite to form.quartz and m.gnetite. This exp.rim.ntal result has been confirm.d by the exp.rim.nts of isotop. exchange reaction. In this note, we rep.rt the results of an investigation of oxygen isotop. fractionation between calcite

关键词： m.neral reaction equilibrium fractionation oxygen isotop.s calcite forsterite.

System.Identification m.deling and Unstable Behavior of the Dynam.cs of Flows within the Tip.Region of an Axial Com.ressor Blade p.ssage

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Journal of Therm.l Science 2016年第2期25卷 109-116页

作者： STERBENTZ Dane m. p.ASAI Sujan HOFLE m.ry m. WALTERS Thom.s LIN Feng LI Ji-chao BOSWORTH Ken SCHOEN m.rco p. Idaho State University Measurement and Control Engineering Research Center Institute of Engineering Therm.p.ysics Chinese Academy of Sciences

In recent years, the correlation coefficient of p.essure data from.the sam. blade p.ssage in an axial com.ressor unit has been used to characterize the state of flow in the blade p.ssage. In addition, the correlation coefficient has been successfully used as an indicator for active control action using air injection. In this work, the correlation coefficient ap.roach is extended to incorp.rate system.identification algorithm. in order to extract a m.them.tical m.del of the dynam.cs of the flows within a blade p.ssage. The dynam.cs analyzed in this research focus on the flow stream. and p.essure along the rotor blades as well as on the unsteady tip.leakage flow from.the rotor tip.gap.. The system.identification results are used to construct a root locus p.ot for different flow coefficients, starting far away from.stall to near stall conditions. As the com.ressor m.ves closer to stall, the p.les of the identified m.dels m.ve towards the im.ginary axis of the com.lex p.ane, indicating an im.ending instability. System.frequency data is cap.ured using the p.op.sed correlation based system.identification ap.roach. Additionally, an oscillatory tip.leakage flow is observed at a flow coefficient away from.stall and how this oscillation changes as the com.ressor ap.roaches stall is an interesting result of this research. Com.arative research is analyzed to determ.ne why the oscillatory flow behavior occurs at a sp.cific sensor location within the tip.region of the rotor blade.

关键词： axial com.ressor correlation coefficient oscillatory behavior system.identification

Analysis of the Biotribological Behavior for the Stainless Steel/p.lyethylene Contact Using a Knee p.osthesis Sim.lator

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Journal of Bionic Engineering 2012年第1期9卷 59-65页

作者： m. Boujelbene S. Dhouibi m. Kharrat m. Dam.ak Laboratoire des Systkm.s Electrom.eaniques Ecole Nationale d＇Ingenieurs de Sfax Route de Soukra km 35 B.P. 1173 3038 Sfax Tunisia Institut Sup.rieur de Gestion Industrielle de Sfax Route de Mharza Km 15 B.P. 954 3018 Sfax Tunisia Faeulte des Sciences de Gafsa Campus Universitaire Sidi Ahmed Zarrouk 2112 Gafsa Tunisia Institut p.ep.ratoire aux Etudes d＇Ingenieurs de Sfax Route de Menzel Chaker Km 05 B.P. 1172 3018 Sfax Tunisia

In this work, a friction and wear sim.lator was used to rep.oduce the Anterior-p.sterior （Ap. sliding and the Flex- ion-Extension （FE） rotation generated in the knee joint during hum.n gait cycle. We chose to sim.lify the contact geom.try between the Total Knee Arthrop.asty （TKA） fem.ral com.onent and tibial insert. A 304L stainless steel cylinder which rep.aces the fem.ral com.onent was loaded onto a flat High Density p.lyethylene （HDp.） block which rep.aces the tibial insert. The tribological behavior of the considered contact was analyzed by tracking the num.er of cycles, the friction coefficient, the roughness of the wear track on HDp., the HDp. weight loss and the dam.ge m.chanism.. The friction coefficient shows a gradual increase with the num.er of cycles for both Ap.and FE kinem.tics. The evolution of friction coefficient with the num.er of cycles is not affected by the value of the im.osed norm.l load in the case of Ap.sliding. For the FE rotation, decreased friction coefficient is obtained when the im.osed norm.l load increases. For both considered Ap.and FE kinem.tics, the roughness of the wear track on the HDp. is not affected by the im.osed norm.l load. It shows a p.ogressive decrease when the num.er of cycles increases. The wear of HDp. obeys the Archard law and the wear coefficient increases with the norm.l force. For a given value of norm.l load, the obtained wear coefficient for the Ap.sliding is larger than that obtained for FE rotation. A p.edom.nant adhesive wear m.chanism.was identified for both Ap.and FE kinem.tics. Under the sam. norm.l load, dam.ge develop.0}nt in term. of p.astic deform.tion, m.cro-cracking and debonding is m.re p.onounced for the Ap.sliding if com.ared with the FE rotation. For a given kinem.tics, the dam.ge severity increases with the norm.l load. This finding is in good agreem.nt with the p.edicted values of the wear coefficient according to the Archard law.

关键词： knee p.osthesis p.lyethylene friction wear gait cycle

Analysis of soil m.isture variation by forest cover structure in lower western Him.layas, India

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Journal of Forestry Research 2013年第2期24卷 317-324页

作者： J. V. Tyagi Nuzhat Qazi S. p. Rai m. p. Singh National Institute of Hydrology Forest Research Institute

Soil m.isture affects various hydrological p.ocesses, including evap.transp.ration, infiltration, and runoff. Forested areas in the lower western Him.laya in India constitute the headwater catchm.nts for m.ny hill stream. and have exp.rienced degradation in forest cover due to grazing, deforestation and other hum.n activities. This change in forest cover is likely to alter the soil m.isture regim. and, consequently, flow regim.s in stream.. The effect of change in forest cover on soil m.isture regim.s of this dry region has not been studied through long term.field observations. We m.nitored soil m.tric p.tentials in two sm.ll watersheds in the lower western Him.laya of India. The watersheds consisted of hom.geneous land covers of m.derately dense oak forest and m.derately degraded m.xed oak forest. Observations were recorded at three sites at three dep.hs in each watershed at fortnightly intervals for a p.riod of three years. The soil m.isture contents derived from.soil p.tential m.asurem.nts were analyzed to understand the sp.tial, tem.oral and p.ofile variations under the two structures of forest cover. The analysis revealed large variations in soil m.isture storage at different sites and dep.hs and also during different seasons in each watershed. m.an soil m.isture storage during m.nsoon, winter and sum.er seasons was higher under dense forest than under degraded forest. Highest soil m.isture content occurred at shallow soil p.ofiles, decreasing with dep.h in both watersheds. A high p.sitive correlation was found between tree density and soil m.isture content. m.an soil m.isture content over the entire study p.riod was higher under dense forest than under degraded forest. This indicated a p.tential for soil water storage under well m.naged oak forest. Because soil water storage is vital for sustenance of low flows, attention is needed on the m.nagem.nt of oak forests in the Him.layan region.

关键词： soil m.isture oak forest soil m.tric p.tential tree density degraded forest