简介：Thehydrolysisreactionof(±)-2-acetamido-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-1],anintermediateofchloramphenicol,wasstudiedandthreedifferentproductswereobtainedrespectivelyunderdifferentreactionconditions.Theresolutionofhydrolysisproduct(±)-2-amino-3-hydroxy-1-(4-nitrophenyl)-1-propanone[(±)-3]wascarriedout.Aprocessofcrystallization-inducedasymmetrictransformationwasobservedandupto76%oftheopticallypureenantiomerwasobtainedintheresolutionof(±)-3.

简介：TofindoptimalconditionsforexpressingthesolubleformofsFv-2F3andtostudythepurificationandpropertyofitsderivativeSe-sFv-2F3,thepreferredexpressionconditionswereinvestigatedbymeansoforthogonaldesign.Thesecultureconditionsincludedincubationtemperature,inducerconcentration,inductiontimeandcellconcentration.TheevaluationofexpressionwasaccomplishedbytheanalysisofwholecelllysatesandtheyieldofsolublesFv-2F3wascalculatedaccordingtotheanalysisofProfinder(FTI-500,Pharmacia).Thepurificationprocedurewascarriedoutviaatwo-steppurificationprocedureconsistingofion-exchangechromatography,followedbyimmobilizedmetalaffinitychromatography(IMAC).TheantioxidantefficacyofSe-sFv-2F3wasdemonstratedbythedeterminationofthecontentofthemainproductoflipidperoxidation,MDA,theviabilityofcellsandtheactivityofLDH.WeobtainedthepreferredcultureconditionstogrowtheengineeredbacteriaandtheprocedureforpreparingsolublesFv-2F3andconfirmedtheantioxidantefficacyofSe-sFv-2F3.

简介：Directasymmetricaldoladditionofmethylketonesto2,2,2-trifluoro-1-phenylethanoneanditsring-substitutedderivativeswasachievedusingL-prolineasachiralpromoter.Variousopticallyactiveβ-trifluoromethyl-β-hydroxyketoneswereobtainedinalmostquantitativeyieldswithmoderateenantioselectivitiesupto64%ee.

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简介：Inthisarticle,nano-scaleAl/Fe2O3compositeswithdifferentmorphologiesweresuccessfullyobtainedbyasimpleelectrospinningtechnique,whichisbasedonasurfactant（polyvinylpyridine,PVP）inamixtureofN,N-dimethylformamide（DMF）and2-propanol.TheelectrospunAl/Fe2O3compositesexhibitedacrystalstructureandphasecompositionbyX-raydiffractionanalysis.ThedifferentmorphologiesoftheAl/Fe2O3compositeswerealsoobservedthroughscanningelectronmicroscopyandtransmissionelectronmicroscopy.Itwasfoundthattherathersimpleelectrospinningmethodusedtopreparethemorphology-controlledAl/Fe2O3compositesmayhavethepotentialforpreparationofpropellants,explosives,andpyrotechnicsinthefuture.

简介：MHP(CH3OOH)和EHP(CH3CH2OOH)的电离精力被方法根据在6-311+G*基础的Koopmans定理设置了的光谱学(足)测量和两个Gaussian-2(G2)计算和Hartree-Fock(HF)第一次铺平的HeI光电子决定了。MHP和EHP的PE系列的任务和描述被G2和HF计算也支持。MHP和EHP的第一个电离精力分别地是9.87和9.65eV。在空气的EHP的更高的溶解度被归因于他们的更低的电离精力价值。

简介：Asupramolecular1Dferromagneticsystemwasstudiedexperimentallyaswellastheoretically.Hybriddensityfunctionaltheory(DFT)calculationswerebasedontheX-rayanalysis.TheresultsofDFTcalculationsandMcConnellmechanismhavecontributedtotheunderstandingofthefactorsgoverningtheexchangecouplingofmagnetisminthecrystalpacking.Boththeexperimentalevidenceandtheoreticalcalculationindicatethatspindensityin2-iodonitronylnitroxide(INN)radicalsconfirms1Dferromagneticchainwithinter-chainantiferromagneticinteraction.

简介：在Au的鼹鼠比率的5nmAuPdnanoalloy:Pd=32:1被准备，作为reductant把钠柠檬酸盐用作稳定的代理人和NaBH4。AuPdnanoalloy被aptamer修改准备aptamer-AuPd(AptAuPd)为回声散布的探查(RS)5.01250nmol/LHg2+的察觉。AptAuPd-Hg2+aptamer反应答案被膜过滤，并且在filtrate的AptAuPd展出了强壮的催化效果在上慢捏粒子反应在之间NiCl2和NaH2PO2，和NiP粒子在508nm显示出一座RS山峰。当Hg2+集中增加了时，RS紧张减少了。减少的RS紧张对在0.51250nmol/L的范围的Hg2+集中线性。RS试金被用来在真实样品决定Hg2+，与好结果。

简介：HighlyactiveandselectiveCu/SiO2catalystsforhydrogenationofdimethyloxalate(DMO)toethyleneglycol(EG)weresuccessfullypreparedbymeansofaconvenientone-potsyntheticmethodwithtetraethoxysilane(TEOS)asthesourceofsilica.XRD,H2-TPR,SEM,TEM,XRFandN2physisorptionmeasurementswereperformedtocharacterizethetextureandstructureofCu/SiO2catalystswithdifferentcopperloadings.TheactivecomponentswerehighlydispersedonSiO2supports.Furthermore,thecoexistenceofCu0andCu+contributedalottotheexcellentperformanceofCu-TEOScatalysts.TheDMOconversionreached100%andtheEGselectivityreached95%at498Kand2MPawithahighliquidhourlyspacevelocityoverthe27-Cu-TEOScatalystwithanactualcopperloadingof19.0%(massfraction).

简介：ThecrystalstructureofN-(2,3,4,6-tetra-O-acetyl-β-D-gly-cosyl)-thiocarbamicbenzoylhydrazine(C22H27N3O9S)wasdeterminedbyX-raydiffractonmethod.Thehexopyranosylringadoptsachairconformation.Alltheringsubstituentsareintheequatorialpositions.Theacetoxyl-methylgroupisinsynclinalconformation.TheSatomisinsynperiplanarconformationwhilethebenzoylhydrazinemoietyisanti-periplanar.Thethiocarbamicmoietyisalmostcompanarwiththebenzoylhydrazinegroup.Therearetwointramolecularhydrogenbondsandoneintermolecularhydrogenbondforeachmoleculeinthecrystalstructure.Themoleculesformanetworkstructurethroughintermolecularhydrogenbonds.

简介：Inthispaper,athiol-functionalizednanophotocatalystMPTES/TiO_2wasfirstsynthesizedbyone-potmethodusingP123asatemplate.X-raydiffractionconfirmsthecompleteanatasecrystallineofthiol-functionalizedTiO_2,N_2adsorption-desorptionisothermdemonstratedthatthesematerialspossesshighsurfaceareaandmesoporousstructure.TheresultsofXPSshowthatMPTEShasbeensuccessfullypolymerizedinmesoporousstructuredTiO_2.Thephotodegradationofphenanthrene(PHE)wasinvestigatedundervisiblelightirradiation(λ>420nm)toevaluatethephotocatalyticactivityofthesematerials.BasedtheexperimentresultsofGC-Massanalysis,apossiblemechanismwasproposed.

简介：应用量子化学ＤＶＸα方法对钌系氰氯络合物进行了系统的理论计算和解析，确定了相应的稳定几何形态和微观电子结构，为合成、应用和深入研究它们的性能提供了重要的理论依据．

简介：ＳＴＵＤＩＥＳＯＮＴＨＥＳＹＮＴＨＥＳＩＳＡＮＤＲＥＡＣＴＩＯＮＷＩＴＨＡＬＫＯＸＩＤＥＳＯＦ３－ＯＸＯ－１，２－ＢＥＮＺＯＩＳＯＴＨＩＡＺＯＬＩＮＥ－２－ＡＣＥＴＡＭＩＤＥ１，１－ＤＩＯＸＩＤＥＳＧｕｏＦｅｎｇＺＨＡＯ；ＨｕａＺｂｅｎｇＹＡＮＧ（Ｉ...

简介：采用重量法对灰岩中的二氧化碳进行测定。首先用酸分解试样，在载气作用下，产生的二氧化碳被吸收液完全吸收，最后用重量法间接求出二氧化碳的含量。实验结果准确度高，矿石中的硫不干扰测定，可测定0．1％以上的二氧化碳。不经过复杂的气体净化步骤，操作准确、简单、易行，可用于灰岩中二氧化碳的测定。

简介：以脂肪二胺为桥联基,通过与β-（3,5-二叔丁基-4-羟基苯基）丙酰氯酰胺化缩合反应,合成了4种脂肪二胺桥联受阻酚.核磁氢谱和质谱证实了脂肪二胺桥联受阻酚的化学结构,采用DPPH法和测氧法对脂肪二胺桥联受阻酚的抗氧化活性进行了研究.结果表明脂肪二胺桥联受阻酚对含氮自由基DPPH和过氧自由基ROO均具有良好的抗氧化活性.随着受阻酚桥联基的增长,受阻酚清除自由基的活性均下降,但随着受阻酚物质的量分数的增加,清除活性均增大,且桥联基对清除DPPH自由基活性的影响大于清除ROO自由基的活性.

简介：应用量子化学从头算HF／3-21G方法，在全局优化中确定贻贝黏附蛋白的强力粘附单元DOPA二联体的几何构型、各原子电荷分布及热力学参数．计算表明：DOPA二联体易与HClO发生亲电取代反应生成2-氯4-酮-5羟基-苯丙氨酸，破坏了贻贝内超强黏附单元DOPA二联体的结构，降低粘附蛋白内粘性；热力学性质的△H放热为88．712kJ／mol，吉布斯自由能变△G恒小于0，较易自发正向进行．

简介：采用甲基纤维素（MC）凝聚剂重量法测定二氧化硅的含量,对溶液体积、甲基纤维素（MC）用量、温度等因素对硅酸凝聚的效果进行了优化研究,并对甲基纤维素凝聚剂与动物胶凝聚剂进行了比较。实验结果表明,在盐酸介质中,甲基纤维素对硅酸有极强的凝聚能力,甚至在室温条件下也能使硅酸大量凝聚。另外在沉淀中夹杂的铁、铝等氧化物少,操作简便,分析时间短。

简介：以2,6-吡啶二酰氯和（邻、间、对）硝基苯胺反应合成N,N-′（2-硝基苯基）-2,6-二甲酰亚胺吡啶、N,N-′（3-硝基苯基）-2,6-二甲酰亚胺吡啶、N,N-′（4-硝基苯基）-2,6-二甲酰亚胺吡啶等3种二硝基化合物,然后以FeCl3-NH2NH2·H2O活性炭为还原体系,将3种二硝基化合物还原成相应的二胺（Ⅰ～Ⅲ）.并用元素分析,FTIR和X射线单晶衍射进行了表征.

简介：通过一种简单的水热法制备了TiO2纳米棒。采用微量稀释法研究TiO2纳米棒对绿脓杆菌的抗菌性能,细菌菌落计数基于光密度测试在96孔细胞培养板上生长的细菌给出。抗菌结果表明,TiO2纳米棒对革兰氏阴性菌(绿脓杆菌)表现出明显的抗菌效率。TiO2纳米棒对绿脓杆菌的抗菌效率达到95.2%。TiO2纳米棒具有优异的抗菌性能。

简介：摘要建立了离子色谱阀切换测定己二酸中痕量阴离子的方法。使用SH-021离子排斥柱将待测痕量阴离子C1-、NO3-、SO4^2-分离出来，再将分离出来的离子通过SH-011浓缩柱进行浓缩富集，最后通过阀切换将浓缩柱中阴离子使用Na2CO3（2．0mmol／L）带人SH-015离子分离柱中分离后分析。方法灵敏度高，重现性好，回收率在87．5％-112．6％，适用于高纯度试剂中痕量阴离子检测。