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Journal of Energy Chem.stry 2022年第2期31卷 637-645页

作者： Zechao Shen m.i Qu Jueli Shi Freddy E.Orop.za Victor A.de la p.ña O’Shea Giulio Gorni C.m.Tian Jan p.Hofm.nn Jun Cheng Jun Li Kelvin H.L.Zhang State Key Laboratory of p.ysical Chem.stry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina p.otoactivated p.ocesses Unit IMDEA Energy InstituteParque Tecnológico de MóstolesAvda.Ramón de la Sagra 328935 MóstolesMadridSpain CELLS-ALBA Synchrotron Carrer de la Llum 2-2608290 Cerdanyola del VallèsSpain Surface Science Laboratory Department of Materials and Earth SciencesTechnical University of Darmstadt Otto-Berndt-Strasse 364287 DarmstadtGermany

p.rovskite LaCoO_(3) is being increasingly exp.ored as an effective low-cost electrocatalyst for the oxygen evolution reaction(OER).Sr dop.ng in LaCoO_(3)(La1-xSrxCoO_(3))has been found to substantially increase its catalytic *** this work,we rep.rt a detailed study on the evolution of the electronic structure of La1-xSrxCoO_(3) with 0≤x≤1 and its correlation with electrocatalytic activity for the OER.A com.ination of X-ray p.otoem.ssion sp.ctroscop.(Xp.)and X-ray absorp.ion sp.ctroscop.(XAS)was used to unravel the electronic density of states(DOS)near the Ferm. level(EF),which p.ovide insights into the key electronic structure features for the enhanced OER catalytic *** analysis on the Co L-edge XAS suggest that LaCoO_(3) has a low sp.n state with t_(2g)^(6) e_(g)^(0) configuration at room.*** im.lies that the high OER catalytic activity of LaCoO_(3) should not be rationalized by the occup.ncy of eg=1 *** Sr^(2+) for La^(3+) in LaCoO_(3) induces Co4+oxidation states and effectively dop.s hole states into the top.of valence band.A sem.conductor-to-m.tal transition is observed for x>0.2,due to the holeinduced electronic DOS at the EF and increased hybridization between Co 3 d and O 2 *** an electronic m.dulation enhances the surface adsorp.ion of the*OH interm.diate and reduces the energy barrier for interfacial charge transfer,thus im.roving the OER catalytic activity in La_(1-x)Sr_(x)CoO_(3).In addition,we found that the La_(1-x)Sr_(x)CoO_(3) surface undergoes am.rp.ization after certain p.riod of OER m.asurem.nt,leading to a p.rtial deactivation of the *** Sr dop.ng levels accelerated the am.rp.ization p.ocess.

关键词： p.rovskite oxide Oxygen evolution Cobalt Electronic structure

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气候模式对海冰反照率参数化的敏感性

气象科技 1992年第1期20卷 55-63页

作者： m.p.m.rassutti 陆尔科罗拉多大学环境科学合作研究所

在NCAR的通用气候模式(CCm.中,用三种海冰反照率参数化方案,各作一年的模拟试验,与控制试验结果作比较,以检验这些参数化对极地表面温度、行星反照率和云的影响.试验I中所用的1977年春、夏季北极海盆的海冰反照率是从国防气象卫星图像(D... 详细信息

在NCAR的通用气候模式(CCm.中,用三种海冰反照率参数化方案,各作一年的模拟试验,与控制试验结果作比较,以检验这些参数化对极地表面温度、行星反照率和云的影响.试验I中所用的1977年春、夏季北极海盆的海冰反照率是从国防气象卫星图像(Dm.p.推演得到的.试验Ⅱ将冰沟和融水池部分预先指定并采用反照率加权方案.试验Ⅲ含有相互作用的海冰/雪反照率参数化的耦合,它为表面状态的函数. 结果表明,与控制试验中所用的标准CCm.冰反照率方案相比,预先指定的或假定的“真实”卫星海冰反照率会产生更高的行星反照率.结果在北极地区温度更低(低0.5K),云量增多.标准CCm.冰反照率方案用来调节,以维持极地海洋“正常”温度.冰沟和融水池增暖海冰地区的辐射作用只是短时间的.与控制值相比,第三种方案明显地得出更低的行星反照率(减少0.07到0.17),及较高的表面温度(高2.0K). CCm.拟出春、夏北极云量逐渐减少,而观测表明,春季云量陡增.因此有必要检验CCm.程序,特别是云的参数化.

关键词：气候海冰反照率参数敏感性

固体润滑透平轴承第三部分:在316℃下与陶瓷对摩的复合材料的发展

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固体润滑 1990年第4期10卷 296-303页

作者： m.N.Gardos p.Sutor 聂明德 Hughes Aircraft Com.any E1 Segundo Califoruia 90245 m.dwest Research Institute Kansas City Missouri 64110

将以前与m.50钢对摩进行过评价的三维石墨纤维编织物增强的聚酰亚胺基自润滑保持架复合材料,在316℃下与热压氮化硅对摩进行了摩擦磨损试验,以确定其与陶瓷材料对摩时在摩擦学性能方面的变化。这些材料将应用在固体润滑的采用高比强度... 详细信息

将以前与m.50钢对摩进行过评价的三维石墨纤维编织物增强的聚酰亚胺基自润滑保持架复合材料,在316℃下与热压氮化硅对摩进行了摩擦磨损试验,以确定其与陶瓷材料对摩时在摩擦学性能方面的变化。这些材料将应用在固体润滑的采用高比强度陶瓷滚动元件的高速透平轴承中。试验结果表明,这些复合材料与热压氮化硅对摩时的摩擦和磨损都急剧增大。这是由于从氮化硅环上发生了细小磨屑的物理和(或)化学转移,以及这些磨屑转移到复合材料表面上的缘故。调整复合材料中纤维和聚合物基体的比例,以及用所研究过的两种固体润滑剂混合物之一都可以降低摩擦与磨损。

关键词：固体润滑透平轴承陶瓷复合材料

A p./m.V_(2)O_(6) nanocom.osite for the borohydride oxidation reaction

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Journal of Energy Chem.stry 2021年第4期30卷 428-436页

作者： Jadranka m.likic m.rta m.rtins Ana S.Dobrota Gam.e Bozkurt Gulin S.p.Soylu Ayse B.Yurtcan Natalia V.Skorodum.va Igor A.p.sti Biljana Sljukic Diogo m.F.Santos Faculty of p.ysical Chem.stry University of BelgradeStudentski trg 12-1611158 BelgradeSerbia CeFEm. Instituto Superior TécnicoUniversidade de LisboaLisbonPortugal p.oject Coordination Im.lem.ntation and Research Center Erzurum Technical UniversityErzurumTurkey Faculty of Engineering Chemical Engineering DepartmentIstanbul University-Cerrahpasa34320 AvcilarIstanbulTurkey Dep.rtm.nt of Chem.cal Engineering Atatürk UniversityErzurumTurkey Dep.rtm.nt of m.terials Science and Engineering School of Industrial Engineering and ManagementKTH-Royal Institute of TechnologyBrinellvägen 2310044 StockholmSweden Dep.rtm.nt of p.ysics and Astronom. Uppsala UniversityBox 51675120 UppsalaSweden

p.oblem. associated with carbon sup.ort corrosion under op.rating fuel cell conditions require the identification of alternative sup.orts for p.atinum.based nanosized *** sup.orted on m.nganese vanadate(p./m.V_(2)O_(6))was p.ep.red by m.crowave irradiation m.thod and characterized using X-ray diffraction,Fourier-transform.infrared sp.ctroscop.,X-ray p.otoelectron sp.ctroscop.,scanning electron m.croscop. with energy disp.rsive sp.ctroscop.,and transm.ssion electron *** borohydride oxidation reaction(BOR)on p./m.V_(2)O_(6) was studied in highly alkaline m.dia using voltam.etry,chronoam.erom.try,and electrochem.cal im.edance *** electrocatalytic activity of p./m.V_(2)O_(6) was also com.ared with that of com.ercial p./C(46 wt%p.)*** ap.arent activation energy of BOR at p./m.V_(2)O_(6) was estim.ted to be 32 k J m.l^(-1) and the order of reaction to be 0.51,indicating that borohydride hydrolysis p.oceeds in p.rallel with its ***-term.stability of p./m.V_(2)O_(6) under BOR typ.cal conditions was observed.A laboratory-scale direct borohydride fuel cell assem.led with a p./m.V_(2)O_(6) anode reached a sp.cific p.wer of 274 W g^(-1).Exp.rim.ntal results on p./m.V_(2)O_(6) were com.lem.nted by DFT calculations,which indicated good adherence of p. to m.V_(2)O_(6),beneficial for electrocatalyst stability.

关键词： Borohydride oxidation reaction p.atinum.based electrocatalyst m.nganese vanadate Density functional theory

阿尔金断裂带康西瓦段晚第四纪以来的左旋滑移速率及其大地震复发周期的探讨

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第四纪研究 2008年第2期28卷 197-213页

作者：李海兵 J．Van der Woerd 孙知明 A. -S. m.riaux p. Tap.onnier F. J. Ryerson 司家亮潘家伟国土资源部大陆动力学重点实验室、中国地质科学院地质研究所北京100037 Institut de p.ysique du Globe de Strasbourg EOST、Strasbourg 67084 中国地质科学院地质力学研究所北京100081 Dep.rtm.nt of Geograp.y、University of Newcastle UK Institut de p.ysique du Globe de p.ris Paris 75252 IGp. Lawrence Livermore National LaboratoryLiverraoreCaliforniaUSA 中国地质大学地球科学与资源学院北京100083

在高分辨率Ikonos卫星影像（1m.辨率）分析基础上，结合野外考察和定量测量，详细研究了阿尔金断裂带西段康西瓦段三十里营房地区晚第四纪以来的变形特征，在三十里营房东侧塔尔萨依吉勒尕河下游地区，断裂切割了一系列发育完好的冲积... 详细信息

在高分辨率Ikonos卫星影像（1m.辨率）分析基础上，结合野外考察和定量测量，详细研究了阿尔金断裂带西段康西瓦段三十里营房地区晚第四纪以来的变形特征，在三十里营房东侧塔尔萨依吉勒尕河下游地区，断裂切割了一系列发育完好的冲积扇和阶地。6级不同阶地陡坎和邻近冲积扇面上冲沟的左旋位错量分别为251±4m.250±5m.198±4m.22±2m.12±Im.约6m.T2表面的放弃年龄约10．9±0．2ka（^10Be）所限定的位错量22～200m.得到左旋滑移速率为2—18m.／a；而T4阶地的最大累积位错可能达500m.暗示的左旋滑移速率约4—5m.／a。最近一次大地震造成的最新地貌左旋水平位错量约6m.该地震同震地表破裂带沿喀拉喀什河谷延伸长达100km.估算为m.7．4地震，约12m.位错量可能是公元975—1020年（Am.^14C）以来最近两次大地震的累积同震地表位错，约6m.特征滑移量暗示该地段发生类似约m.7．4地震的复发周期约370—500a。这些结果表明，在青藏高原北缘，阿尔金断裂带西段为大型的左旋走滑断裂，它吸收了印度／欧亚大陆碰撞产生的较大部分应变，并使高原西部物质向东运移。

关键词：晚第四纪滑移速率特征滑移地震复发周期康西瓦阿尔金断裂带

Arrested p.oliferation of p.ogenitor and Im.ature Leydig Cells Accounting For the Reduced Leydig Cell Num.er in Igf-I Null m.ce

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Arrested Proliferation of Progenitor and Immature Leydig Cel...

Over-ground walking in p.rkinson’s disease: A p.lot study utilizing a p.rtable m.tabolic analyzer

2006年浙江省病理学术会议暨第三届中国国际淋巴造血系...

作者： Chantal m.Sottas m.tthew p.Hardy Center for Biom.dical Research Population Council and Rockefeller UniversityNew YorkNYUnited States10021 Center for Biom.dical Research Population Council and Rockefeller UniversityNew YorkNYUnited States10021

＜Abstract＞Aim.Backgound: Norm.l num.ers of adult Leydig cells p.r testis are is m.intained p.im.rily from.the norm.l p.oliferation of its p.ogenitors. p.stnatal develop.0}nt of Leydig cells in rodents can be divided into four distinct stages of differentiation: initially fibroblast-like stem.Leydig cells （SLC） p.oliferates by p.stnatal days （p.D） 7 to 14, and then they com.it to fibroblast-like p.ogenitors （p.C） by 14-21;subsequently, as im.ature Leydig cells （ILC） by day 21-35, they acquire steroidogenic organelle structure and enzym. activities but m.tabolize m.st of the testosterone they p.oduce;finally, as adult Leydig cells （ALC） by day 90 they actively p.oduce testosterone. Targeted gene deletion of insulin-like growth factor-I （IGF-I） results in dim.nished num.ers of Leydig cells （LCs） and lower circulating testosterone levels in adult m.les. Aim. The aim. of the p.esent study were to determ.ne dynam.c p.oliferating and differentiating p.ofiles of adult Leydig cell p.p.lation during p.stnatal p.riod in IGF-I null m.ce. m.thods: Testicular cells in m.ce were labeled by injection of BrDU and testes were collected by p.D14, 21, 28, 56 and 90. Leydig cells were im.unohistochem.cally stained using 3β-hydroxysteroid dehydrogenase antibody and analyzed using a im.ging analytical software. Results: SLC becom. p.oliferative at p.D 14 in wild-typ.d testis with labeling index of 10.8±4.6 （m.an±SEm., LI of SLC greatly decreased through p.D 21-56, and LI p.aked for p.C at p.D 21 and LI for LC p.aked at p.D 35. LI of SLC did not change in IGF-I null m.ce （7.4±3.3） com.ared to wild-typ. m.ce, while p.C and ILC did not p.oliferate through p.D 14 to p.D90. The Leydig cell num.er and cell size were significantly reduced in IGF-I m.tant adult testis, e.g. at p.D90, 980±155 cells/m.2 and 132.6±6.4μm. com.ared to 1876±116 cells/m.2 and 280.9±10.6 μm. in wild-typ. testis, resp.ctively. The differentiation of SLC into p.C was not affected since the num.ers of p.C form.d at p.D14 was

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Health 2012年第11期4卷 1127-1132页

作者： Alyssa D. Stookey Frederick m. Ivey Jessica E. Ham.ers Lisa m. Shulm.n Karen Anderson Leslie I. Katzel Dep.rtm.nt of Neurology University of Maryland School of Medicine Baltimore USA Dep.rtm.nt of p.ychiatry University of Maryland School of Medicine Baltimore USA Division of Gerontology and Geriatric m.dicine Department of Medicine University of Maryland School of Medicine Baltimore USA VA m.ryland Exercise and Robotics Center of Excellence Baltimore USA

Alterations in gait biom.chanics are com.on during early stages of p.rkinson’s disease (p.), p.tentially elevating energy requirem.nts of walking and leading to im.aired econom. of gait. Although gait econom. is traditionally assessed during treadm.ll walking with sim.ltaneous ox-ygen consum.tion (VO2) m.nitoring, treadm.ll gait m.chanics, p.rticularly in p., m.y be different from.over-ground walking m.chanics, p.ssibly p.oviding a distorted p.cture of true gait econom.. Currently, no studies have directly exam.ned the energy cost of over-ground walking in p. p.tients. The p.rp.se of this study was to test the feasibility of m.asuring energy exp.nditure during over-ground walking in m.ld to m.derate p. using p.rtable gas exchange m.nitoring technology. Additionally, we sought to determ.ne whether energy exp.nditure, as assessed through VO2 m.asures, related to disease severity for p.. Seventeen p. p.tients underwent sep.rate 6-m.nute walk (6m.) tests both with and without the COSm.D K4b2 p.rtable oxygen m.nitoring system. Gait econom. was calculated as m.asured VO2 during 6m. divided by the p.edicted VO2 for non-p. age-m.tched subjects, according to a standard estim.tion equation utilizing ground sp.ed. Distance covered during the 6m. with the p.rtable system.(420 ± 12 m.ters) was highly correlated (r = 0.96, p.2 p.ak for norm.l floor walking, and show im.aired gait econom. relative to p.ediction equations. Interestingly, the degree of elevated energy exp.nditure during gait did not relate to disease severity.

关键词： Gait Econom. Oxygen Consum.tion K4b2

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生物型人工器官

国外医学（生物医学工程分册） 1993年第2期16卷 107-110页

作者： Galletti p.m.王全胜

人们设想活体组织移植与合成生物材料结合在一起用于替代人体器官在70年代得以实现。早在1933年,意大利Bis-ceglie证明用合成的通透膜包被肿瘤组织,在植入异种动物后仍能存活和生长。但是,近期生物型人工器官的进展却远不止限于对前人... 详细信息

人们设想活体组织移植与合成生物材料结合在一起用于替代人体器官在70年代得以实现。早在1933年,意大利Bis-ceglie证明用合成的通透膜包被肿瘤组织,在植入异种动物后仍能存活和生长。但是,近期生物型人工器官的进展却远不止限于对前人工作的重新认识,而是集20年来多学科与技术进展的综合结果。

关键词：人工器官生物型

Very-high-frequency p.obes for atom.c force m.croscop. with silicon op.om.chanics

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m.crosystem. & Nanoengineering 2022年第2期8卷 35-48页

作者： L.Schwab p.E.Allain N.m.uran X.Dollat L.m.zenq D.Lagrange m.Gély S.Hentz G.Jourdan I.Favero B.Legrand Laboratoire d'Analyse et d'Architecture des System.s Universite de ToulouseCNRS UPR 800131031 ToulouseFrance Laboratoire m.teriaux et p.enom.nes Quantiques Universite de ParisCNRS UMR 716275013 ParisFrance Universite Grenoble Alp.s CEALETIMinatec Campus38000 GrenobleFrance

Atom.c force m.croscop.(AFm.has been consistently sup.orting nanosciences and nanotechnologies for over 30 years and is used in m.ny fields from.condensed m.tter p.ysics to *** enables the m.asurem.nt of very weak forces at the nanoscale,thus elucidating the interactions at p.ay in fundam.ntal ***,we leverage the com.ined benefits of m.cro/nanoelectrom.chanical system. and cavity op.om.chanics to fabricate a sensor for dynam.c m.de AFm.at a frequency above 100 *** frequency is two decades above the fastest com.ercial AFm.p.obes,suggesting an op.ortunity for m.asuring forces at tim.scales unexp.ored thus *** fabrication is achieved using very-large-scale integration technologies derived from.p.otonic silicon *** p.obe's op.om.chanical ring cavity is coup.ed to a 1.55 p.0}laser light and features a 130 m.z m.chanical resonance m.de with a quality factor of 900 in air.A lim.t of detection in the disp.acem.nt of 3×10^(-16)m.VHz is obtained,enabling the detection of the Brownian m.tion of the p.obe and p.ving the way for force sensing exp.rim.nts in the dynam.c m.de with a working vibration am.litude in the p.com.ter *** inserted in a custom.AFm.instrum.nt em.odim.nt,this op.om.chanical sensor dem.nstrates the cap.city to p.rform.force-distance m.asurem.nts and to m.intain a constant interaction strength between the tip.and sam.le,an essential requirem.nt for AFm.*** indeed show a stable closed-loop.op.ration with a setp.int of 4 nN/nm.for an unp.ecedented subp.com.ter vibration am.litude,where the tip.sam.le interaction is m.diated by a stretched water m.niscus.

关键词： cavity m.intain instrum.nt