简介：利用同步辐射X光衍射技术，对（La1-xBix)0.5Ca0.5MnO3(x=0.2,0.3,0.4）中存在的Jahn-Teller畸变，进行了原位的高压研究。实验表明在外加压力的作用下，能有效地影响到晶格中Mn-O键长和Mn-O-Mn键角的变化，样品中的晶格畸变有所减小。并且对在晶格中存在的两种不同的畸变模式Q2和Q3，在外加压力的作用下的变化规律进行了讨论。由于这两种不同的畸变模式在受到外力作用时，表现形为不一样，导致了位于a-b基面上的Q2畸变模式的消失，并且导致Q2畸变模式消失的压力点随掺杂浓度的增加而增加。

简介：在同步辐射软X光能区（50－2000eV)进行了硅光电二极管的自标定实验，因为消除了二极管的“死区”并采用很薄层的SiO2作窗，使得可以用简单的模型来分析实验结果，由实验测得的光电流，计算出硅光电二极管的量子效率，并求得入射同步辐射的光通量。

简介：对于x从0．0到0．4之间变化的Pt1-xSrxMnO3多晶体所进行的价带光电子能谱实验显示，在Fermi边和Fermi边以下－12eV范围内出现的能带态密度随掺杂量x有一个显著的变化。对这些现象以Pr1-xSrxMnO3体系在基态下发生电荷转移为出发点进行了讨论。提出了随掺杂量x的非线性电荷转移机制和存在由电荷转移导致的二级相变的可能性。

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简介：我们用XPS和同步辐射技术研究了钙钛矿型氧化物SrTi1-xSbxO3(x=0,0.05,0.10,0.15,0.20）薄膜的电子结构。该薄膜系列在可见光波段透明，其透过率均超过90％。所有掺杂薄膜均导电。同步辐射电子能谱研究结果表明该薄膜中来自Sb杂质的退局域化电子在母化合物的禁带中引入了杂质能级。这是导电性的根源，价带中很小的电子态密度限制了跃迁几率。大的禁带宽度和小的跃迁几率是光学透明性的原因。

简介：

简介：随着北京同步辐射光电子能谱实验站持续稳定的开放运行，用户基于该实验站提供的光电子能谱各种实验模式开展了从金属表面界面电子结构到纳米材料、掺杂金属富勒烯以及磁电阻氧化物体系电子结构的研究工作。本文中选择部分具有代表性的实验结果进行介绍。

简介：采用在位高压Raman光谱和高压同步辐射能散X射线衍射技术，在室温下对晶粒尺寸为10nm的锐钛矿TiO2进行了压致相变研究，压力范围分别为42．9GPa和23．0GPa，实验结果表明，在16．3GPaTiO2发生了一次结构相变，由原来的锐钛矿结构变为α－PbO2结构（TiO2-Ⅱ），该相变是不可逆的。同体材料TiO2的高压相变结果比较，由于晶粒尺寸的效应，纳米尺寸的锐钛矿TiO2的相变压力明显高于体材料的相变压力。

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简介：本文介绍了同步辐射光源的特点，以及在应用于X射线形貌术时带来的各种好处。并通过介绍在北京同步辐射装置上所做的若干实验成果，扼要叙述了同步辐射X射线形貌术在晶体缺陷研究和晶体生长中的应用。

简介：Characteristicsofiontemperaturemeasuredwithcharge-exchangerecombinationspectroscopy（CXRS）werestudiedinOhmic,lower-hybrid-wave（LHW）drivenandion-cyclotron-resonance-frequency（ICRF）heatedplasmasinHT-7.TheresultsindicatethatthecentraliontemperatureTi0followstheone-thirdpowerlawintheproductofcentralline-averageddensityneandplasmacurrentIpinOhmicdischargesandisthereforeconsistentwiththeArtsimovichscalinglawTi0=K·（Ip·Bt·ne·R2）1/3.ItisshownthatthereisanappreciableincreaseofiontemperatureduringtheoperationwithbothLHWandICRFandthattheincrementofiontemperatureinthoseshotsismainlyduetotheenergytransferviacollisionsbetweenionsandelectronsratherthatbydirectheatingoftheions.

简介：SawtoothcontrolexperimentswereperformedonHT-7withalimiterconfigurationandontheExperimentalAdvancedSuperconductingTokamak(EAST)withadoublenullcon-figuration.Thesawtoothperiodcanbemodifiedbylowerhybridwave(LHW)andioncyclotronresonancefrequency(ICRF).Differentsawtoothbehaviorwasobservedwiththesameplasmadensity,LHWpowerbutdifferentplasmacurrentsonHT-7.TherewasadwelltimebetweenLHWaddedandthesawtoothstabilizationonHT-7whilethesawtoothstabilizationimmediatelyhappenedwhenLHWpowerwasinjectedonEAST.Thepossiblemechanismofthesawtoothcontrolisdiscussedinthispaper.Alltheexperimentalresultshaveprovedthatpowerdepositionoftheradiofrequency(RF)shouldbethekeyfactorforsawtoothcontrol.

简介：实验观测到X射线反向曲线具有双晶特征。研究表明缺陷聚集在孪晶晶界。应力在晶界边缘处得到释放。应力的释放导致享晶和其它缺陷的形成。由于缺陷的形成在缺陷的附近产生无位错无应力或低位错小应力区。因此我们提出一种孪晶模型来解释实验结果。应力（主要是热应力），化学配比的偏离和杂质的非均匀分布是液封直接（LEC）InP单晶生长过程中产生孪晶的主要因素。研究了液封直拉（LEC）InP(111）面上的孪晶。本文中讨论了上面提到的孪晶模型的实验证据和如何得到无孪晶液封直接（LEC）InP单晶。

简介：

简介：Experimentsonlowerhybridwave(LHW)couplingwereinvestigatedintheHT-7tokamak.GoodcouplingofLHWplasmahasbeendemonstratedatdifferentconditionsintheHT-7tokamak.RelevantresultshaveprovedthatLHW-plasmacouplingisaffectedbythephasedifferencebetweenadjacentwaveguides.Furthermore,theedgedensityaroundthegrillandrelevantcouplingcanbeadjustedbychangingtheplasmalineaveragedensityorthegapvaluebetweentheLHgrillandthelastclosedfluxsurfaces(LCFS).ItisfoundthatthecouplingofLHWsbecomespoorwhentheedgedensityaroundtheLHgrillislargeenoughintheHT-7tokamak,andthatcouplingremainsgoodwithaproperedgedensity.WithincreasingLHWpower,itisalsofoundthatthereflectioncoefficients(RCs)increaseduetonon-lineareffectsunderconditionsoflowedgerecycling,butcandecreaseunderhighedgerecycling.Theedgedensitydependsmainlyonthecompetitionbetweentheponderomotiveforce(PMF)andtheedgerecyclingintensityintheHT-7tokamak.

简介：SawtoothactivityonHT-7tokamakhasbeeninvestigatedexperimentallymainlybyusingsoftx-raydiodearrayandmagneticprobes.Theirbehaviorsandoccurrencesarecorrelatedcloselytothedischargeconditions:theelectrondensityNe,theelectrontemperatureTe,thesafetyfactorqaonplasmaboundaryandwallconditionetc.Whencentralline-averagedelectrondensityNe(0)isover2.0×1013cm-3,majorsawtoothactivityemergeswithaperiodofupto6.5msandafluctuationamplitudeofupto2～30%ofSXRradiationsignal.Insomecasessuchasthesafetyfactorbetween4.2～4.7andZeff=3.0～6.0,amonstersawtoothactivityoftenemergeswithoutapparentdeteriorationofplasmaconfinementandwithoutmajordisruption.Duringtheseevents,abundantMHDphenomenaareobservedincludingpartialsawtoothoscillations.Inthispaper,theobservedsawtoothbehaviorsandtheirdependenceontheandtheirdependencedensityNeandwallconditioninohmicallyheatedplasmaareintroduced,theresultsarediscussedandpresented.

简介：TheICRF(IonCyclotronRangeFrequency)cleaningtechniquehasbeenusedasaroutinewallcleaningmethodintheHT-7superconductingtokamak.Inawiderangeoftoroidalfield,thcremovalrateofresidualgasbyICRFcleaningwasabouttwentytimeshigherthanthatofglowdischargecleaning(GDC).AtdifferentgaspressureandRFpowerlevels,theICRFcleaningisstudiedcarcfully.Agoodimpurityclcaningeffectandaveryhighhydrogenremovalratewereobtained.Theremovalrateofhydrogenby5kWICRFcleaningachievedwas1.6×10-5Torr.1/s.AndtherelationshipsamongpressureP,outgassingrateQ,atomiclayersLabsorbedonsurfaceandthecleaningmodewerediscussedbriefly.

简介：Thispaperreportsforthefirsttimeanexperimentalstudyonthepowerdepositionprofileoftheioncyclotronrangefrequencies(ICRF)powerdepositingonelectronsinHT-7.ThefastFouriertransform(FFT)analysisandthebreakinslope(BIS)methodareutilizedtoobtaintheinformationofthepowerdeposition.Theresultsindicatethattheelectronswereheateddirectly,andtheelectronsabsorbedaround20%oftheinputpowerofthedischargeofinterest.

简介：Togetanoptimizedpulsedelectricalplasmadischargereactorandtoincreasetheenergyutilizationefficiencyintheremovalofpollutants,twohybridplasmadischargereactorsweredesignedandoptimized.Thereactorswerecomparedviathedischargecharacteristics,energytransferefficiency,theyieldsoftheactivespeciesandtheenergyutilizationindyewastewaterdegradation.TheresultsshowedthatunderthesameACinputpower,thecharacteristicsofthedischargewaveformofthepoint-to-platereactorwerebetter.UnderthesameACinputpower,thetworeactorsbothhadalmostthesamepeakvoltageof22kV.Thepeakcurrentofthepoint-to-platereactorwas146A,whilethatofthewire-to-cylinderreactorwasonly48.8A.Thepeakpowersofthepoint-to-platereactorandthewire-to-cylinderreactorwere1.38MWand1.01MW,respectively.Theenergyperpulseofthepoint-to-platereactorwas0.2221J,whichwasabout29.4%higherthanthatofthewire-to-cylinderreactor（0.1716J）.Toremove50%AcidOrange7（A07）,theenergyutilizationsofthepoint-to-platereactorandthewireto-cylinderreactorwere1.02×10-9mol/Land0.61×10-9mol/L,respectively.Inthepoint-toplatereactor,theconcentrationofhydrogenperoxideinpurewaterwas3.6mmol/Lafter40minofdischarge,whichwashigherthanthatofthewire-to-cylinderreactor（2.5mmol/L）.Theconcentrationofliquidphaseozoneinthepoint-to-platereactor(5.7×10-2mmol/L)wasabout26.7%higherthanthatinthewire-to-cylinderreactor(4.5×10-2mmol/L).Theanalysisresultsofthevarianceshowedthatthetypeofreactorandreactiontimehadsignificantimpactsontheyieldsofthehydrogenperoxideandozone.ThemaindegradationintermediatesofA07identifiedbygaschromatographyandmassspectrometry（GCMS）wereaceticacid,maleicanhydride,pbenzoquinone,phenol,benzoicacid,phthalicanhydride,coumarinand2-naphthol.Proposeddegradationpathwayswereelucidatedinlightoftheanalyzeddegradationproducts.