简介：在在热退火之上的低精力和高剂量他植入6H-SiC的水泡进化被学习。面向的6H-SiC晶片在房间温度在11017厘米2的剂量与15个keV氦离子被植入。样品与培植以后为30min在1073，1173，1273，和1473K的温度被退火。他在晶片起泡经由代表性的传播被检验电子显微镜学(XTEM)分析。nanoscale水泡在同样植入的样品的损坏的层是几乎同类地分布式的在场的结果，和没有重要变化在退火的1073K以后在他植入样品被观察。在退火的1193K之上，在6H-SiC的He-implantation-inducedamorphization的几乎完整的再结晶被观察。另外，直径他起泡显然增加。与不断地增加温度到1273K和1473K，直径他起泡增加和格子缺点的数字密度减少。生长在退火的高温度接受成熟的Ostwald以后，他起泡机制。吝啬的直径他作为退火的一个函数在120-135nm的深度定位的水泡温度被装入产出1.914+0.236eV的一个激活精力的热激活的进程的术语。
简介：Anewadaptivetechniqueofr-andh-versionforvibrationproblemsutilizingthematrixper-turbationtheoryandelementenergyratioisproposed.Instructuralvibrationanalysis,throughther-conver-genceadaptivefiniteelementprocess,meshoptimizationcanberealized.Inthelightofthejudgementonthechangesinthemagnitudeoftheelementenergyratio,localrefinementcanbeachievedintheprocessofh-convergenceadaptivefiniteelementsothatmoreaccuratefiniteelementsolutionscanbeobtainedwithasfewmeshesaspossible.Manynumericalexamplesaregivenandtheproposedapproachisshowntobefeasibleandeffective.
简介：Siliconcarbidefiber/siliconcarbidematrix(SiCf/SiC)compositesareofinterestasafuelcladdingandstructuralmaterialindesignsofadvancednuclearreactorduetotheirsuperiorthermo-mechanicalpropertiesandstabilitiesandlowcross-sectionforneutroncaptureunderthesevereserviceenvironmentincludinghightemperatureandhighenergyneutronbombardment.SiCf/SiCcompositionsconsistsofSiCfiberandSiCmatrixwhichexistinwellover100polymorphsdependentonthevariedstackingofSi-Cclose-packedatomicplanes,2H-SiC,4H-SiC,6H-SiC,3C-SiC,15R-SiC,etc.EnergeticHeatomscanbecreatedandaccumulatedvianuclearreactions.HeatomsagglomerateandcoarsenintoHebubblesandcandeterioratestructuralpropertiesbyinducingcrackandcreep.Inthisexperiment,thedamageofn-type4H-SiCwafers(researchstandard,suppliedbytheCreeResearchInc.)withathicknessof0.38mmimplantedwith100keVHe+toafluenceof31016He+/cm2andpost-implantation-annealedbehavioratdifferenttemperaturewerestudiedusingRamanscatteringspectroscopy.
简介：TheAlkalineThermalTreatment（ATT）ofbiomassisoneofthefewbiomassconversionprocessesthathasapotentialforBECCS（bio-energywithcarboncaptureandstorage）.Combiningin-situcarboncapturewithcreatesacarbon-neutralprocessthathasthepotentialtobecarbon-negative.Thisstudyhasshownthattheconversionofcellulosetosuppressedcanbeachievedthroughthereformingofgaseousintermediatesinafixedbedof10%Ni/ZrO2.Reformingoccursatlowtemperatures≤773K,whichcouldallowforimprovedsustainability.
简介：Ahighlyeffcientandgeneralmethodforthesynthesisofpolyfunctionalized4H-pyransisestablishedthroughaone-potmulticomponentcyclocondensationofaromaticaldehydeswithCHacids,malononitrileandethylacetoacetateusingnanosilicasupportedtin(II)chlorideasacatalyst.InthismethodSnCl2/nanoSiO2wasusedasgreenandreusablecatalyst.Excellentyields,shortreactiontimes,simpleworkup,andinexpensivenessandcommerciallyavailabilityofthecatalystaretheadvantagesofthismethod.
简介：应用密度泛函理论DFT方法，在B3LYP／6—311G（d，p）水平上研究了不饱和类锗烯H2C=GeNaBr的结构及异构化反应．结果表明，不饱和类锗烯H2C=GeNaB。有3种平衡构型，其中非平面的p-配合物型构型能量最低，是其存在的主要构型．并对平衡构型间异构化反应的过渡态进行了计算，求得了转化势垒，预言了最稳定构型的振动频率和红外强度．
简介：ＡＣＩＤＩＴＹ ＡＮＤ ＣＡＴＡＬＹＴＩＣ ＡＣＴＩＶＩＴＹ ＯＦ ＫＥＧＧＩＭ ＳＴＲＵＣＴＵＲＥ ＨＥＴＥＲＯＰＯＬＹＡＣＩＤＳ ──ＥＦＦＥＣＴ ＯＦ ＣＥＮＴＲＡＬ ＡＴＯＭ ＩＮ Ｈ＿α ＸＷ＿（１２） Ｏ＿（４０）ＡＣＩＤＩＴＹＡＮＤＣＡ...
简介：Thetitlecomplexi-C4H9Co（salen）（Py）（Py=pyridine.salen=dianionofdisalicylideneethylenediamine）hasbeenfirstsynthesized.ItscrystalstructurehasbeendeterminedbyX-raydiffractionmethod.ThecrystsisaremonoclinicwithspacegroupP21/C.Theunitcellparametesarepresented.ThestructurehasbeenrefinedtoafinalRof0.038.
简介：采用铜（Ⅱ）盐和3,5-二氯水杨醛缩丝氨酸以及4,4′-联吡啶在乙醇水溶液中合成了具有二维层状的配位聚合物.通过元素分析、红外光谱对该配位聚合物进行了表征,并利用X射线单晶衍射仪对其结构进行了鉴定.晶体结构表明,该标题配合物属三斜方晶系,空间群C2/c,晶胞参数为a=2.711（3）nm,b=2.711（3）nm,c=4.977（5）nm;α=90.00°,β=90.00°,γ=120.00°,V=3.1678nm^3,Z=18,Dc=1.173g·cm^-3,F（000）=11448,μ=0.807mm-1,R1=0.0788,wR2=0.1872.
简介：通过水热法合成了一维链状的磷钼氧酸盐（DETA）。NaNa（H5P4Mo6O31）2]·8H2O（DETA—Diethylenetriamine），采用x-射线单品衍射结构分析，元素分析和红外光谱等表征．该磷钼氧酸盐属于三斜晶系，空间群是P-1，晶胞参数a=1．2434（3）nm，6—1．2610（3）nm，c=1．3079（3）nm，a=85．418（3）°，β=73．399（2）°），γ=82．175（3）°，V=1．9450（8）Elm。，F（000）=1462，Z=：=2．标题化合物的结构是由Na（H5P4Mo6O31）2簇单元，二亚乙基三胺阳离子和结晶水分子组成．另外，Na（H5P4Mo6O31）2簇由钠离子连接形成了一维的链结构．一维链结构又由于二亚乙基三胺阳离子和结晶水分子形成的氢键进一步连接三维超分子结构．用标题化合物修饰的碳糊电极（APM—CPE）对AA氧化有很好的电催化活性．
简介：Tetrabutylammoniumorpotassiumsaltsoforganometalllicderivativesoflacunarypolyanion(RM)3P2W15O59^n-(RM=CpTi,CpZr,C4H7O2SnorC5H9O2Sn)havebeenpreparedandstructurallycharacterizedbyelementalanalysis,IR,UV-Vis,^1HNMRand^183WNMRspectroscopies.Thetitlecomplexesexhibitantitumoractivityinvitro.
简介：Anefficientsynthesisoffunctionalized4H-chromenesbythetandemreactionofb,g-unsaturatedaketoesterswith2-naphthols,1-naphthols,and1,3-dihydroxynaphthaleneshasbeenaccomplishedwithhighselectivityandexcellentyieldsinthepresenceofacatalyticamountofbismuthtriflate[Bi(OTf)3,5mol%]undermildconditions.Thefunctionalized4H-chromenesynthesisandourprevious2Hchromenehemiacetalsynthesiscouldcomplementeachothertoenrichreactiondiversity.
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