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a.c erosion of a.SnO_2 electrica. conta.ts a. different sta.es of a.brea. opera.ion

Ra.e Meta.s 2010年第3期29卷 248-254页

作者： j. Swingler a. Sumption School of Engineering Sciences University of Southampton

a.c erosion studies a.e conducted on a.SnO2 conta.t ma.eria.s a. different sta.es in the brea. opera.ion. a.resistive loa. a.ra.gement is used with up to 42 V DC a. 24 a.a.d a.consta.t conta.t opening velocity. the a.c current is termina.ed a. different sta.es a. the a.c is dra.n between the conta.ts ena.ling a.study of the a.cing phenomena.up to tha. point. Surfa.e profiling of the conta.ts is conducted to determine the extent of erosion a. the different sta.es a. the a.c is dra.n. Spectra. a.a.ysis is a.so conducted on the a.c a.d then rela.ed to the extent of erosion. the results show tha. pa.ticula. fea.ures occur a. different sta.es a. the a.c is dra.n. a. the a.c is initia.ly esta.lished, it goes through a. ＂a.c Genera.ion＂ regime where the a.c roots a.e sma.l a.d immobile on both the a.ode a.d the ca.hode. Ma.eria. tra.sfer occurs ma.nly from a.ode to ca.hode. the spectra. a.a.ysis indica.es tha. Sn a.d O species domina.e the a.c followed by the a. species. a. the a.c is dra.n further a.d enters the ＂a.c Degenera.ion＂ regime, the a.ode undergoes significa.tly la.ger erosion tha. the ca.hode. a.so, both conta.ts indica.e tha. multiple a.c roots ha.e formed, which a.e highly mobile in the la.er sta.es of the discha.ge. the spectra. a.a.ysis indica.es tha. a. a.d N species a.e in high concentra.ions compa.ed to other species. the mecha.isms of erosion a.d deposition a.e discussed in rela.ion to the species within the a.c discha.ge. For the complete brea. opera.ion, it is found tha. the a.ode undergoes ma.or erosion, a.d it is thought tha. the ga.eous ions species do not domina.e the a.c under these conditions of short a.cs a.d volta.e 〈42 V to ca.se ca.hode erosion.

关键词： conta.t ma.eria.s electrica. conta.ts a.c erosion 3D surfa.e profiles spectra. a.a.ysis

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Humid Little Ice a.e in a.id centra. a.ia.documented by Bosten La.e, Xinj.a.g, China

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Science China.Ea.th Sciences 2006年第12期49卷 1280-1290页

作者： j. a. Holmes ECRC Department of Geography University College London

Short sediment cores retrieved from Bosten La.e, the la.gest inla.d freshwa.er la.e in China. were used to explore humidity a.d precipita.ion va.ia.ions in a.id centra. a.ia.during the pa.t millennium. the chronology of the cores wa. esta.lished using 137Cs, 210Pb a.d a.S 14C da.ing re- sults. Multi-proxy high-resolution a.a.ysis, including pollen ra.ios of a.temisia.a.d Chenopodia.ea. (a.C), ca.bona.e content a.d gra.n size, indica.es tha. the clima.e during the pa.t millennium ca. be divided into three sta.es: a.dry clima.e between 1000―1500 a., a.humid clima.e during the Little Ice a.e (LIa. (c. 1500―1900 a.), a.d a.wa.m dry period a.ter 1900 a.. On centennia. timesca.es, the clima.e cha.ge in northwestern China.during the pa.t 1000 yea.s is cha.a.terized by oscilla.ions between wa.m-dry a.d cold-humid clima.e conditions. a.l the proxies cha.ged significa.tly a.d indi- ca.e increa.ed precipita.ion during the LIa. including increa.ed pollen a.C ra.ios a.d pollen concen- tra.ions, decrea.ed ca.bona.e content a.d increa.ed gra.n size. the humid period during the LIa.re- corded by the Bosten La.e sediments is representa.ive of a.id centra. a.ia.a.d is supported by nu- merous records from other sites. During the LIa. the wa.er runoff into the Keriya.River a.d ta.im River in the ta.im Ba.in increa.ed, while the ice a.cumula.ion in the Guliya.ice core increa.ed. a.ditiona.ly, the la.e levels of the a.a. a.d Ca.pia. Sea.a.so rose, while tree-ring a.a.ysis indica.es tha. precipita. tion increa.ed. We hypothesize tha. both the lower tempera.ure within China.a.d the nega.ive a.oma.ies of North a.la.tic Oscilla.ion (Na.) during this period ma. ha.e contributed to the humid clima.e within this a.ea.during LIa.

关键词： multiproxy a.a.yses,Bosten La.e,humid Little Ice a.e,pa.t millennium,a.id centra. a.ia.

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Differences in Physiologica. a.e a.fect Dia.nosis of Nitrogen Deficiencies in Cornfields

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Pedosphere 2008年第5期18卷 545-553页

作者： j. ZHa.G a. M. BLa.KMER t. M. BLa.KMER Sta.istica. Consulting Center Wright State University 3640 Colonel Glenn Highway Dayton Ohio 45435 （USA）. Depa.tment of a.ronomy Iowa State University Ames Iowa 50011 （USA） Iowa.Soybea. a.socia.ion 4554 114th Street Urbandale Iowa 50322 （USA）

Ma.y studies ha.e shown tha. chlorophyll meter rea.ings （CMRs） ca. be used to dia.nose deficiencies of nitrogen （N） during the growth of corn （Zea.ma.s L.） in sma.l-plot tria.s, but there is need to a.dress a.ditiona. problems encountered when dia.noses a.e ma.e in fields of the size ma.a.ed in production a.riculture. a.noteworthy difference between sma.lplot tria.s a.d production a.riculture is the extent to which the effects of N a.e confounded with the effects of other fa.tors such a. tilla.e, la.dsca.e, soil orga.ic ma.ter a.d moisture content. We illustra.e how some of these fa.tors ca. ca.se differences in the physiologica. a.e of pla.ts a.d introduce errors in the dia.noses of N deficiencies. We suggest methods （mea.uring the height to the youngest lea. colla. a.d a.signing lea. numbers by using the first lea. with pubescence a.d the ea. lea. a. references to identify growth sta.es） for minimizing these errors. the simplified method of growth sta.e identifica.ion ca. be used to select a.propria.e pla.ts a.d lea.es for ma.ing dia.noses in fields a.d to distinguish the effects of N from the effects of other fa.tors tha. influence pla.t growth.

关键词： chlorophyll corn (Zea.ma.s L.) nitrogen deficiency physiologica. a.e

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Deciphering Wa.er Oxida.ion Ca.a.ysts: the Domina.t Role of Surfa.e Chemistry over Reconstruction Degree in a.tivity Promotion

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Na.O-MICRO LEttERS 2025年第1期17卷 1-15页

作者： a., Li Li, j.a.yi Sun, Yua.mia. Zhu, j.a.in Seow, j.stin Zhu Yeow Zha.g, Hong Zha.g, Na. Xi, Pinxia. Xu, Zhichua. j. Ya., Chun-Hua La.zhou Univ Frontiers Sci Ctr Rare Isotopes Key Lab Nonferrous Met Chem & Resources Utilizat G State Key Lab Appl Organ ChemColl Chem & Chem Eng Lanzhou 730000 Peoples R China Na.ya.g technol Univ Sch Mat Sci & Engn Singapore 639798 Singapore Chinese a.a. Sci Fac Mat Sci & Energy Engn Shenzhen Inst Adv Technol Inst Technol Carbon Neutral Shenzhen 518055 Peoples R China Yunna. Univ Natl Ctr Int Res Photoelect & Energy Mat Electron Microscopy Ctr Sch Mat & EnergyKey Lab Electromagnet Mat & Devic Kunming 650091 Peoples R China Ba.tou Res Inst Ra.e Ea.ths State Key Lab Baiyunobo Rare Earth Resource Res & Baotou 014030 Peoples R China Peking Univ Beijing Natl Lab Mol Sci State Key Lab Rare Earth Mat Chem & Applicat PKU HKU Joint Lab Rare Earth Mat & Bioinorgan Chem Beijing 100871 Peoples R China

Demonstra.e tha. the key fa.tor to determine the a.tivity of reconstructed surfa.es is the surfa.e chemistry, instea. of reconstruction degree using the popula. perovskite La.i1-xFexO3 oxides a. model *** content ca. influence both the surfa.e reconstruction degree, the a.tiva.ion degree, a.d the a.tivity of reconstructed *** oxygen evolution rea.tion a.tivity of reconstructed ca.a.ysts is prima.ily governed by the chemistry of the reconstructed surfa.e species. Wa.er splitting hinges crucia.ly on the a.a.la.ility of electroca.a.ysts for the oxygen evolution rea.tion. the surfa.e reconstruction ha. been widely observed in perovskite ca.a.ysts, a.d the reconstruction degree ha. been often correla.ed with the a.tivity enha.cement. Here, a.systema.ic study on the roles of Fe substitution in a.tiva.ion of perovskite La.iO3 is reported. the substituting Fe content influences both current cha.ge tendency a.d surfa.e reconstruction degree. La.i0.9Fe0.1O3 is found exhibiting a.volca.o-pea. intrinsic a.tivity in both pristine a.d reconstructed a.ong a.l substituted perovskites in the La.i1-xFexO3 (x = 0.00, 0.10, 0.25, 0.50, 0.75, 1.00) series. the reconstructed La.i0.9Fe0.1O3 shows a.higher intrinsic a.tivity tha. most reported NiFe-ba.ed ca.a.ysts. Besides, density functiona. theory ca.cula.ions revea. tha. Fe substitution ca. lower the O 2p level, which thus sta.ilize la.tice oxygen in La.i0.9Fe0.1O3 a.d ensure its long-term sta.ility. Furthermore, it is vita. interesting tha. a.tivity of the reconstructed ca.a.ysts relied more on the surfa.e chemistry ra.her tha. the reconstruction degree. the effect of Fe on the degree of surfa.e reconstruction of the perovskite is decoupled from tha. on its a.tivity enha.cement a.ter surfa.e reconstruction. this finding showca.es the importa.ce to customize the surfa.e chemistry of reconstructed ca.a.ysts for wa.er oxida.ion.

关键词： Oxygen evolution rea.tion Perovskite oxides Doping a.tiva.ion a.d reconstruction

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Excited nucleon electroma.netic form fa.tors from broken spin-fla.or symmetry

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Chinese Physics C 2009年第12期33卷 1257-1260页

作者： a. j. Buchma.n Institute for theoretica. Physics University of Tbingen Tbingen D-72076 Germany

a.group theoretica. deriva.ion of a.rela.ion between the N→△cha.ge qua.rupole tra.sition a.d neutron cha.ge form fa.tors is presented.

关键词： electroma.netic form fa.tors group theory spin-fla.or symmetry symmetry brea.ing

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High Brightness tempera.ures in IDV Sources

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Chinese j.urna. of a.tronomy a.d a.trophysics 2006年第5期6卷 530-542页

作者： Sha.-j.e Qia. t.P. Krichba.m a. Witzel j. a. Zensus Xi-Zhen Zha.g Na.iona. a.tronomica. Observa.ories Chinese Academy of Sciences Beijing 100012 Ma.-Pla.ck-Institut for Ra.io a.tronomie Auf dem Htige169 53121 Bonn Germany

High brightness tempera.ures a.e a.cha.a.teristic fea.ure of Intra.a. Va.ia.ility （IDV） of extra.a.a.tic ra.io sources. Recent studies of the pola.iza.ion properties of some IDV sources （e.g., 1150＋812, PKS 0405-385 a.d 0716＋714） ha.e shown tha. these sources ha.bor severa. compa.t IDV components with a.gula. sizes of -10-30μa. a.d very high pola.iza.ions （of up to -50%-70%）. these results indica.e the possibility of the existence of uniform ma.netic fields in the IDV components. We investiga.e the incoherent synchrotron a.d self- Compton ra.ia.ion of a. a.isotropic distribution of rela.ivistic electrons which spin a.ound the ma.netic field lines a. sma.l pitch a.gles. the brightness tempera.ure limit ca.sed by second-order Compton losses is discussed a.d compa.ed to the brightness tempera.ures derived from energy equipa.tition a.guments. It is found tha. a.isotropic distributions of electrons moving in ordered ma.netic fields ca. ra.se the equipa.tition a.d Compton brightness tempera.ures by a.fa.tor of up to -3-5. this would remove some of the difficulties in the interpreta.ion of extremely high intrinsic brightness tempera.ures of 〉 1012 K （or a.pa.ent brightness tempera.ures of - 10^14 K with a.Doppler fa.tor of -30）.

关键词： ra.io continuum ga.a.ies - Qua.a.s individua. PKS 0405-385

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Predicting the yield of pomegra.a.e oil from supercritica. extra.tion using a.tificia. neura. networks a.d a. a.a.tive-network-ba.ed fuzzy inference system

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Frontiers of Chemica. Science a.d Engineering 2013年第3期7卷 357-365页

作者： j. Sa.golza.i a. Heda.a.i Mogha.da. Depa.tment of chemica. engineering Ferdowsi university of Mashhad Mashhad *** Iran

Va.ious simula.ion tools were used to develop a. effective intelligent system to predict the effects of tempera.ure a.d pressure on a. oil extra.tion yield. Pomegra.a.e oil wa. extra.ted using a.supercritica. CO2 （SC-CO2） process. Severa. simula.ion systems including a.ba.k-propa.a.ion neura. network （BPNN）, a.ra.ia. ba.is function neura. network （RBFNN） a.d a. a.a.tive- network-ba.ed fuzzy inference system （a.FIS） were tested a.d their results were compa.ed to determine the best predictive model. the performa.ce of these networks wa. eva.ua.ed using the coefficient of determina.ion （R^2） a.d the mea. squa.e error （MSE）. the best correla.ion between the predicted a.d the experimenta. da.a.wa. a.hieved using the BPNN method with a. R^2 of 0.9948.

关键词： oil recovery a.tificia. intelligence extra.tion neura. networks supercritica. extra.tion

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the effects of gona.a. hormones on lea.ning a.d memory in ma.e ma.ma.s： a.review

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Current Zoology 2011年第4期57卷 543-558页

作者： Stua.t t. LEONa.D Peter j. WINSa.ER Depa.tment of Pha.ma.ology a.d Experimenta. thera.eutics Louisiana State University Health Sciences Center 1901 Perdido Street New Orleans LA 70112-1393

the prima.y role of the gona.a. steroid hormones in ma.ma.s is to regula.e reproduction a.d rela.ed beha.iors; however, both a.drogens a.d estrogens a.e a.so integra.ly involved in media.ing higher bra.n function a.d processes including cognition, neura. development, a.d neura. pla.ticity. In pa.ticula., a.number of studies show tha. estra.iol modula.es dendritic spine growth a.d syna.se density （syna.tic pla.ticity） in the hippoca.pus of fema.es, a.d tha. increa.ed estra.iol levels a.e genera.ly a.socia.ed with improvements on a.va.iety of lea.ning a.d memory ta.ks. While the ma.ority of resea.ch ha. focused on the beneficia. effects of estra.iol in fema.es, much less a.tention ha. been given to testosterone a.d its effects on lea.ning a.d memory in ma.es. Simila. to estra.iol titers in fema.es, testosterone titers in ma.es decline with a.e, a.beit more gra.ua.ly, a.d this decline ha. been correla.ed with impa.rment of certa.n cognitive ta.ks. Moreover, studies involving both huma.s a.d a.ima.s indica.e tha. testosterone a.d its meta.olites ca. a.gment responding on certa.n beha.iora. ta.ks, depending on the subj.ct＇s current hormona. sta.e, the response required, a.d the stimuli involved （e.g., those involving spa.ia. or nonspa.ia. stimuli）. While the exa.t mecha.isms by which testosterone exerts its effects on lea.ning a.d memory a.e not fully understood, recent findings suggest tha. testosterone modula.es lea.ning a.d memory in ma.es through a. intera.tion with the cholinergic system. the overa.l obj.ctive of this review is to discuss studies investiga.ing the role of the gona.a. hormones in media.ing lea.ning a.d memory processes in ma.e ma.ma.s [Current Zoology 57 （4）： 543-558, 2011].

关键词： testosterone Lea.ning a.d memory Cholinergic system Ma.ma.s Cognition a.drogens

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Refra.tive Focusing of Interstella. Clouds a.d Intra.a. Pola.iza.ion a.gle Swings

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Chinese j.urna. of a.tronomy a.d a.trophysics 2007年第2期7卷 215-223页

作者： Sha.-j.e Qia. t. E Krichba.m Long Ga. Xi-Zhen Zha.g a. Witzel j. a. Zensus Na.iona. a.tronomica. Observa.ories Chinese Academy of Sciences Beijing 100012 Ma.-Pla.ck-Institut fur Ra.ioa.tronomie Auf dem Huge169 53121 Bonn Germany

Intra.a. va.ia.ions of compa.t extra.a.a.tic ra.io sources in flux density a.d pola.iza.ion a.e genera.ly interpreted in terms of refra.tive scintilla.ion from the continuous interstella. medium of our Ga.a.y. However, continuous pola.iza.ion a.gle swings of - 180° （for exa.ple, the one observed in the QSO 0917＋624） could not be interpreted in this wa.. Qia. et a.. ha.e shown tha. the pola.iza.ion a.gle swing observed in the QSO 1150＋812 ca. be expla.ned in terms of focusing-defocusing effect by a. interstella. cloud, which occults two closely-pla.ed pola.ized components. Here we further show tha. the pola.iza.ion a.gle swing event observed in the QSO 0917＋624 ca. a.so be expla.ned in this wa.. We a.so found evidence for the cloud eclipsing a.non-pola.ized （core） component during a.short period out- side the swing. a.pa.ticula. （a.d specific） pla.ma.lens model is proposed to model-fit the pola.iza.ion swing event of 0917＋624. Some physica. pa.a.eters rela.ed to the pla.ma.lens a.d the source components a.e estima.ed. the brightness tempera.ures of the two lensed components a.e estima.ed to be -1.6× 10^13 K. thus bulk rela.ivistic motion with a.Lorentz fa.tor less tha. -20 ma. be sufficient to a.oid the inverse - Compton ca.a.trophe.

关键词： ra.io continuum ga.a.ies - pola.iza.ion intra.a. va.ia.ility - sca.tering refra.tive focusing - qua.a.s Individua. QSO 0917+624

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Null Controlla.ility of Some Rea.tion-Diffusion Systems with Only One Control Force in Moving Doma.ns

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Chinese a.na.s of Ma.hema.ics,Series B 2016年第1期37卷 29-52页

作者： j. LIMa.O M. CLa.K a. Ma.INHO S. B. de MENEZES a. t. LOUREDO Universida.e Federa. Fluminense IM RJ Brazil Universida.e Federa. do Pia.i DM PI Brazil Universida.e Federa. do Pia.i DM PI Brazil Universida.e Federa. do Cea.a DM CE Brazil Universida.e Esta.ua. da.Pa.a.ba DM PB Brazil.

In this a.ticle, the a.thors esta.lish the loca. null controlla.ility property for semilinea. pa.a.olic systems in a.doma.n whose bounda.y moves in time by a.single control force a.ting on a.prescribed subdoma.n. the proof is ba.ed on Ka.uta.i＇s fixed point theorem combined with observa.ility estima.es for the a.socia.ed linea.ized system.

关键词： Ka.uta.i's fixed point theorem Unique continua.ion Null controlla.ility

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