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简介：Themicrostructuresofloadedorganicphasesofthreequaternaryaminesolventextractionsystemsforgold,whichwereN263-xylene,N263-tributylphosphate(TBP)-dodecaneandN263-2-ethylhexanol(isooctanol)-dodecane(N263-trialkylmethylammoniumchloride;alkyl=C8-C10),werestudiedbyFouriertransforminfrared(FTIR)spectroscopyandextendedX-rayabso\rptionfinestructure(EXAFS)spectroscopy.AccordingtotheEXAFSresults,itwasfoundthatthegoldcoordinationenvironmentwasthesamebeforeandafterextraction.However,theC≡NstretchingvibrationsofAu(CN)2-werealsofoundtobedifferent,InordertoexplainthedifferencesintheIRcharacteristicsofC≡Ninthethreeextractionsystems,threemicrostructuremodelsareproposed.FortheN263-xylenesystem,themodelisasimpleionpair.Fortheothertwosystemswithamodifier(TBPandisooctanol),themodelsaretwosupramolecularstructuesbasedonhydrogenbondingbetweenthemodifierandAu(CN)2^-.SomerelatedworksuchasonthehydrationofacetonitrileandthefinestructureofC≡NinsolidKAu(CN)2wasalsoperformedinordertoofferadditionalsupportingevidenceforthereliabilityoftheproposedmodels.

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简介：本文利用沉淀法制备了粒度分窄，无明显团聚的ZrO2纳米微粒。考察了ZrO2纳米微粒修饰丝光沸石对二甲苯异构化的影响。实验结果表明，经修饰后的丝光沸石催化剂能有效地抑制副反应的发生，提高二甲苯异构化的选择性，超微粒子修饰的丝光沸石的催化活性和选择性明显优地体相材料修饰的样品。

简介：本文对合成制备的LiNiO2、LiCo2和LiNixCo1-xO2正极材料以及稀土金属Ce元素添加改性的正极材料进行了XRD和EXAFS表征。结果表明，随着焙烧温度的升高，物相组成趋于单一，晶格趋向完整，800℃时完全形成LiNiO2、LiCoO2晶相结合。LiNiCoO2样品中Ni/Co比不影响LiNiO2晶相的形成，而只影响其晶相组成；掺杂的稀土金属Ce元素以CeO2状态存在于产物中，CeO2对LiNiO2晶相形成有一定的影响；LiCoO2的焙烧温度不能大于900℃，否则Co被氧化为Co3O4；样品中Ni与Co原子的局域结构，除Ni与Co原子相互影响外，掺杂Ce后对它们的局域结构也有较大影响。

简介：通过原位浸渍法把FeSO4和其它助剂共同浸渍在两种烟煤上，考察了以FeSO4为主要前驱体的催化剂对这两种煤直接液化的活性与选择性，以及其对液化产物－甲苯可溶物分子量的影响作用，并通过EXAFS和SAXS表征揭示了催化剂在煤上的化学态和粒径分布，结果表明：在一定的反应条件下，FeSO4和两种助剂分别共浸渍在两种煤上时，煤的总转化率及沥青烯和轻质产物的产率均比不添加催化剂时的结果提高1倍左右，与铁的硫化物相比，以FeSO4为主要前驱体的催化剂沥青烯和轻质产物具有较高的选择性，生成的重质甲苯可溶物具有较大的分子量；EXAFS和SAXS表明，原位浸渍在煤上的FeSO4表现为纳米相，助剂Na2S和尿素的添加主要改变了Fe原子周围的配位原子种类以及它们的成键方式，而对其颗粒分布影响较小，催化剂在汾西煤上的分布较其在兖州煤上的差一些。

简介：ToobtainthermotolerantmutantsofG.oxydans,whichcanenhancethetransformationrateofL-sorboseto2-Keto-L-gulonate(2-KLG)at33℃inatwo-stepprocessofvitaminCmanufacture,ionbeamwasusedasamutationsource.GluconobacteroxydansGOandBacillusmegateriumB0wereusedinthisstudy.TheoriginalstrainGluconobacteroxydansGOwasmutatedbytheheavyionimplantationfacilityattheInstituteofPlasmaPhysics,ChineseAcademyofSciences.SeveralmutantsincludingGluconobacteroxydansGI13wereisolatedandcoculturedwithBacillusmegateriumB0at33℃inshakingflasks.TheaveragetransformationrateofthenewmixedstrainGI13-B0inpergram-moleculereached94.4%aftersevenpassagesinshakingflasks,whichwasincreasedby7%whencomparedwiththeoriginalmixedstrainG0-B0(GluconobacteroxydansG0andBacillusmegateriumB0).Moreover,thetransformationrateofI13B0wasstableat94%attemperaturesrangingfrom25℃to33℃,whichwouldbeofmuchvalueinreducingenergyconsumptioninthemanufactureofL-ascorbicacid,especiallyintheseasonofsummer.Toclarifysomemechanismofthemutation,thespecificactivitiesofL-sorbosedehydrogenaseinbothG0andGI13wereestimated.

简介：InthedischargeofEASTtokamak,itisobservedthat（2,1）neoclassicaltearingmode（NTM）istriggeredbymodecouplingwitha（1,1）internalmode.Usingsingularvaluedecomposition（SVD）methodforsoftX-rayemissionandforelectroncyclotronemission（ECE）,thecouplingspatialstructuresandcouplingprocessbetweenthesetwomodesareanalyzedindetail.TheresultsofSVDforECErevealthatthephasedifferencebetweenthesetwomodesequalstozero.Thisisconsistentwiththeperfectcouplingcondition.Finally,performingstatisticalanalysisofγ1/1,ζ1/1andω2/1,wefindthatγ1/1moreaccuratelyrepresentsthecouplingstrengththanζ1/1,andγ1/1isalsostronglyrelatedtothe（2,1）NTMtriggering,whereγ1/1isthewidthof（1,1）internalmode,ζ1/1istheperturbedamplitudeof（1,1）internalmode,andω2/1denotesthemagneticislandwidthof（2,1）NTM.

简介：Thisworkinvestigatesinternalplasmaprocessparametersusingahairpinresonanceprobeandopticalemissionspectroscopy.ThedependenceofelectrondensityandatomicfluorineonthepercentageofoxygeninanSF6/O2dischargewasmeasuredusingthesemethods.AnRIEOxfordInstruments80pluschamberwasusedfortheexperiments.Twodifferentprocesspowers(100Wand300W)ataconstantpressure(100mTorr)wereused,anditwasfoundthattheopticalemissionintensityofthe703.7nmand685.6nmlinesofatomicfluorineincreasedrapidlyasoxygenwasaddedtotheSF6discharge,reachedtheirmaximumatanO2fractionof20%andthendecreasedwithfurtheradditionofoxygen.TheplasmaelectrondensitywasalsostronglyinfluencedbytheadditionofO2.

简介：WehavedevelopedaplasmaetchingsimulatortoinvestigatetheevolutionofpatternprofilesinSiO2materialunderdifferentplasmaconditions.Thismodelfocusesonenergyandangulardependentetchingyield(physicalsputteringinthispaper),neutralandionangulardistributions,andreflectionofionsorneutralsonthesurfaceofaphotoresistorSiO2.TheeffectofpositivechargeaccumulationonthesurfaceofinsulatedmaskorSiO2isstudiedandthechargeaccumulationcontributestoadeflectionofiontrajectory.Thewaferprofileevolutionhasbeensimulatedusingacellular-automata-likemethodunderradio-frequency(RF)biasanddirect-current(DC)bias,respectively.Onthebasisofthecriticalroleofangulardistributionofionsorneutrals,thewaferprofileevolutionhasbeensimulatedfordifferentvariancesofangles.Observedmicrotrenchinghasbeenwellreproducedinthesimulator.Theratioofneutralstoionshasbeenconsideredandtheresultshowsthatbecausetheneutralsarenotacceleratedbyanelectricfield,theirenergyismuchlowercomparedwithions,sotheyareeasilyreflectedonthesurfaceofSiO2,whichmakesthetrenchshallower.

简介：Magneticspectrumoftheelectromagneticioncyclotronwavesintheterrestrialplasmadepletionlayer（PDL）aresometimesobservedtohaveaBIF（bifurcated）signature,whereadiminutionaround0.5ΩpwithΩptheprotongyrofrequency,occursbetweentwoactivitypeaksinthespectrum.Byone-dimensionalhybridsimulations,theeffectofrelativedriftvelocitiesbetweenprotonsandHe2+onthemagneticspectralsignaturesinthePDLisstudied.Theresultsshowthattherelativedriftvelocityenhancesthedevelopmentofprotoncyclotronwavesanddeclinesthedevelopmentofheliumcyclotronwaves.Theprotoncyclotronwavesarefirstlyexcited,andfollowedbytheexcitationofheliumcyclotronwavesduetotheincreaseintherelativedriftvelocity.Moreover,theboundarybetweentwoactivitypeaksgetsobscure.

简介：利用同步辐射（BSRF）漫散射站四圆衍射仪，对SiC体单晶的结构进行了判定以及对利用常压化学气相沉积（APCVD）生长的3C－SiC/Si(001）中的孪晶及含量进行了分析。六方{10-15}极图证明了该SiC单晶为6H（H为Hexagonal的缩写）结构。对3C－SiC外延薄膜，Φ扫描证明了3C－SiC外延生长于Si衬底上，外延取向关系为：（001）3C－SiC//(001)Si,[111]3C-SiC//[111]Si。3C－SiC的{111}极图在x=15.8°出现了新的衍射，采用六方{10-10}极图以及基体倒格点111、孪晶倒格点002的Mapping分析了x=15.8°处产生的衍射为3C－SiC孪晶所致，并利用ω扫描估算了孪晶的含量约为1％。

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简介：AnovelfittingprocedureisproposedforabetterdeterminationofH2rovibrationaldistributionfromtheFulcher-abandspectroscopy.WehaverecalculatedthetransitionprobabilitiesandtheresultsshowthattheydeviatefromFranck-Condonapproximationespeciallyforthenon-diagonaltransitions.Wealsocalculatedthecompletesetsofvibrationallyresolvedcrosssectionsforelectronimpactd3∏u-X3∑gtransitionbasedonthesemi-classicalGryzinskitheory.AnexampleofexperimentalstudyconfirmsthatcurrentapproachprovidesatoolforabetterdiagnosticsofH2rovibrationaldistributioninelectronicgroundstate.

简介：本文测定了在高压条件下两种金属（钙和锌）的8－羟基喹啉络合物的晶体粉末样品的发光行为和原位x-光衍射光说。结果表明，压力对其发光性质产生极大的影响。随着压力的增加，8－羟基喹啉钙的发光强度在3GPa以内时大大增加。随后发光强度快速下降，到7GPa左右时几乎为零。而8－羟基喹啉锌的发光随压力的增加而逐渐降低，到7GPa左右时常压的10％。高压下的原位x－光衍射结果表明8－羟基喹啉钙的晶体在3－4GPa开始发生非晶化相变，在7GPa时该非晶化相变完成，样品的x－光衍射完全消失。而8－羟基喹啉锌在压力的作用下（至16GPa）没有发生明显的相变。