简介:AsfarasChina-USrelationsareconcerned,theTibetissueisoneofthosethatappearedonlyinthepast100years.IthasneverbeenanessentialoneinChina-USrelations.However,fromthedaythatthePeople'sRepublicofChina(PRC)wasestablished,theTibetissueturnedouttobealong-termfactorwhichhasexertedaninfluenceontherelationsbetweenthetwocountriesoveranextendedperiodoftime.
简介:内在的hydrogenated非结晶的硅(a-Si:H)电影在n类型上被扔由到分析的热电线的化学蒸汽免职(HWCVD)的水晶的硅(c-Si)晶片非结晶/水晶的heterointerface钝化性质。对称的heterostructure的少数搬运人一生被使用请教WCT-120一生测试者系统,和决定从一生测量的接口状态密度被建议的一个简单方法的Sinton测量。接口状态密度测量被使用深水平的短暂光谱学(DLTS)证明简单方法的有效性也执行。微观结构和a-Si的氢结合配置:有不同的氢冲淡的H电影被使用分光镜的ellipsometry(SE)和Fourier变换调查红外线的光谱学(FTIR)分别地。接口状态密度的更低的值被使用a-Si获得:有水晶的硅上的更一致的、紧缩的微观结构和更少体积缺点的H电影由HWCVD扔了。
简介:Background:Withthelossofspeciesworldwideduetoanthropogenicfactors,especiallyinforestedecosystems,ithasbecomemoreurgentthanevertounderstandthebiodiversity-ecosystemfunctioningrelationship(BEFR).BEFRresearchinforestedecosystemsisverylimitedandthusstudiesthatincorporategreatergeographiccoverageandstructuralcomplexityareneeded.Methods:Wecompiledground-measureddatafromapprox.onehalfmilionforestinventorysampleplotsacrossthecontiguousUnitedStates,Alaska,andnortheasternChinatomaptreespeciesrichness,foreststocking,andproductivityatacontinentalscale.Basedonthesedata,weinvestigatedtherelationshipbetweenforestproductivityandtreespeciesdiversity,usingamultipleregressionanalysisandanon-parametricapproachtoaccountforspatialautocorrelation.Results:Ingeneral,forestsintheeasternUnitedStatesconsistedofmoretreespeciesthananyotherregionsinthecountry.ThehighestforeststockingvaluesovertheentirestudyareawereconcentratedinthewesternUnitedStatesandCentralAppalachia.Overall,96.4%ofsampleplots(477,281)showedasignificantpositiveeffectofspeciesrichnessonsiteproductivity,andonly3.6%(17,349)hadaninsignificantornegativeeffect.Conclusions:Thelargenumberofground-measuredplots,aswellasthemagnitudeofgeographicscale,renderedoverwhelmingevidenceinsupportofapositiveBEFR.Thisempiricalevidenceprovidesinsightstoforestmanagementandbiologicalconservationacrossdifferenttypesofforestedecosystems.Foresttimberproductivitymaybeimpairedbythelossofspeciesinforests,andbiologicalconservation,duetoitspotentialbenefitsonmaintainingspeciesrichnessandproductivity,canhaveprofoundimpactsonthefunctioningandservicesofforestedecosystems.
简介:类蚜虫属Linnaeus的发展史,1 758首先从在美国的中西部收集的标本被造。一个数据矩阵与有翼、无翅的胎生的女性的各自的字符国家与68种类和41个词法字符被构造。用UPGMA(有算术平均数的未加权的对组方法)执行的分析的Dendrogram拓扑学,最大的吝啬和细胞色素Oxidase的贝叶斯的分析我,延伸因素1-α并且主要endosymbiontBuchneraaphidicola16S序列不适合。贝叶斯的分析强烈支持了种系发生的树的大多数终端节点。发展史被COI的EF1-α和EF1-α强烈支持分子的数据与词法人物结合了。它没被COI或Buchneraaphidicola16S的单个分析支持。从贝叶斯的发展史的结果给4个主要种类组看:asclepiadis,fabae,gossypii,和middletonii。结果地方蚜虫属和类ProtaphisBörner的种类,1952,ToxopteraKoch,1856并且XerobionNevsky,1928在monophyleticclade。词法人物也monophyly支持这。发展史证明北美的middletonii种类组的monophyleticclade属于类Protaphis:P。debilicornis(吉勒特与帕尔默,1929),梳子。nov,P。echinaceae(拉各斯和Voegtlin,2009),梳子。nov,和P。middletonii(托马斯,1879)。类Toxoptera应该被认为蚜虫属的亚属(stat。nov)。分析也显示当前的类IowanaFrison,1954应该被认为蚜虫属的亚属(stat。nov)。
简介:WithintheframeworkoftheUsdpf(16)interactingbosonmodel(IBM),theeffectsofstrongcorrelationsofthedipole(p--boson)andtheoctupole(f--boson)degreeoffreedomonthepositive-paritystatesofeven-evennucleiinSU(3)limitarediscussed.Itisshownthatconfigurationsofanevennumberofmanyp-andf-bosonscannotonlybeincorporatedintotheusuallow-lyingcollectiverotationalbands,suchasthegroundstateband,β-andγ-vibrationalbands,butalsonaturallyformtheKπ=1+,3+rotationalbands,etc.TheseresultsaresimilartothatofUsdg(15)-IBMandinagreementwellwiththeexperimentaldataofthe17672Hf104nucleus.Besides,severalintrabandE2transitionprobabilitiesaregiven,whichareconsistentwiththatofUsd(6)-IBM.
简介:Amethodtopreparemulti-particleentanglementofGreenberger-Horne-Zeilinger-typeandW-typeisproposedthroughtheinteractionbetweenthecavityandmanyatomssimultaneously.Aftersuitableinteraction,theselectedmeasurementsonthecavityfieldcancreatetheentangledatomicstates.Theseentangledstatescanbeusefulforquantuminformationmanipulationandfundamentalstudyofquantumtheory.ThesestatesthatviolatetheBell'sinequalityareproven.
简介:Weinvestigatemodulationalinstability(MI)ofacoupledtwo-componentBose–Einsteincondensatesinarotatingringtrap.TheexcitationspectrumandtheMIconditionofthesystemarepresentedanalytically.WefindthatthecouplingbetweenthetwocomponentsstronglymodifiestheMIcondition,andtheMIconditionisphase-dependent.Furthermore,wediscusstheeffectofMIonbothdensityexcitationandspinexcitation.Iftheinter-andintra-componentinteractionstrengthsareallequal,theMIcausesdensityexcitationbutnotspinexcitation,andiftheinter-andintracomponentinteractionstrengthsaredifferent,theMIcausesbothdensityexcitationandspinexcitation.Ourresultsprovideapromisingapproachforcontrollingthestabilityandexcitationofarotatingtwo-componentBose–Einsteincondensatesbymodulatingitscouplingstrengthandinteractionstrength.