简介:Thecrystalstructureofthetitlecomplex{[Co(TCB)2/2-(IMI)2(H2O)2][Co(IMI)4(H2O)2]}(H2O)4(whereTCB=1,2,4,5-benzenetetracarboxylicanion;IMI=imidazole)hasbeendeterminedbyX-raydiffractionmethod.Crystaldatafor{[Co(TCB)2/2(IMI)2(H2O)2][Co(IMI)4(H2O)2]}-(H2O)4:triclinic,spacegroupP1,a=1.0647(2)nm,b=1.1165(1)nm,c=1.00361(1)nm,α=91.56(1)°,β=111.34(1)°,γ=115.642(10)°,V=0.9772(3)nm5,Z=1.Thepolymercobalt(II)complexhasanovelthree-dimensionnetworkstructure.Co(1)atomandCo(2)atombotharecoordinatedinanoctahedralarrangementandlocatedinthecenterofthecoordinationanionandthecenterofthecoordinationcation,respectively.MoreoverfourcarboxylgroupsofTCBaredividedintotwotypes,twopara-carboxylgroupsbridgeCo(1)atominmonodentatefashionandothertwopara-carboxylgroupsareinfree.
简介:Twosolubleisomerizedpolyimides(PIs)synthesizedfrom2,2'-bis(3,4-dicarboxyphenyl)hexafluoropropanedianhydride(6FDA)witheither2,2'-dimethylbenzidine(2,2'-DMB)or3,3'-DMBwereinvestigatedbymeansofsize-exclusionchromatographycoupledwithmulti-anglelaserlightscattering,aviscometerandarefractiveindexdetectorintetrahydrofuran(THF)withtetrabutylammoniumbromide(TBAB)at35℃.Thecorrespondingparametersrelatedtoconformationsαandν,evaluatedfromthescalingrelationships[η]=KηMαandRg=KgMν,respectively,were0.66±0.01and0.55±0.02forpoly(6FDA/3,3'-DMB),and0.67±0.01and0.56±0.01forpoly(6FDA/2,2'-DMB),indicatingarandomcoilconformationforboththesamplesinthismobilesystem.ThepersistencelengthlpandshiftfactorML(relativemolecularweightperunitcontourlength)wereestimatedfromtherelationshipbetweenintrinsicviscosityandmolecularweightforthewormlikecylindermodelproposedbyBohdanecky.BothlpandMLshowedthatthetwoPIsinTHFareflexiblechainsandexhibitsomelocalrigiditytosomeextent.
简介:Theepoxideisakindofversatileintermediateformanufactureofawidevarietyoffinechemicals.Thegoalofmodemefficientcatalyticmethodsistoproducedesiredcompoundswithhighyield,selectivity,lowcost,safety,operationalsimplicityandmoreimportantlyenvironmentallybenignmanner.However,therearevariousoxidants,whichareoftenhazardousorexpensive,beingusedforbothlaboratoryandindustrialepoxidation.Hydrogenperoxide(30wt%)solutionisthoughtasoneoftheidealoxidantsbecausewaterisasoletheoreticalsideproduct.Meanwhiletheepoxidationofstyreneisatypicaloneamongolefins.Here,theperformanceofstyreneepoxidationwasstudiedwithhydrogenperoxidesolutioncatalyzedbyCo(Ⅱ)phenanthrolinecomplexencapsulatedinsupercagesofMCM-41.
简介:到目前为止它是不清楚的是否演变氧的建筑群(OEC)的版本包括PsbO,PsbP,和PsbQ蛋白质的子单元被photosystemII(PSII)膜的phosphorylation在轻应力下面影响。在这个工作,不同phosphorylatedPSII膜从菠菜被获得。Phosphorylation部分在轻应力下面从PSII膜压制了PsbO,PsbP,和PsbQ蛋白质的版本。反应的氧种类包括superoxide阴离子,氢过氧化物和氢氧根基,在non-phosphorylated和phosphorylatedPSII膜涉及PsbO蛋白质的小部分的版本,然而并非在PsbP和PsbQ蛋白质的版本。建议的结果,PsbO,PsbP,和PsbQ蛋白质的版本部分是,这phosphorylation在PSII膜调整的所有,和在在non-phosphorylatedPSII膜的OEC子单元的版本的反应的氧种类的角色与在phosphorylatedPSII膜一样。
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简介:Benzodiazepineandbenzothiazepinederivativeshavebeenwellknownastherapeuticallyimportantcompounds.Fournewtricyclicheterocycliccompounds,3a,4,5,11-tetrahydro-3H-1,2,4-triazolo[4,3-d][1,5]benzothiazepines(3),3a,4,5,11-tetrahydro-3H,6H-1,2,4-triazolo[4,3-d][1,5]benzodiazepine(4),3a,4,5,11-tetrahydro-1,2,4-oxadiazolo[4,5-d][1,5]benzothiazepines(5,6)and3a,4,5,11-tetrahydro-6H-1,2,4-oxadiazolo[4,5-d][1,5]benzodiazepines(7,8),havebeensynthesizedby1,3-dipolarcycloadditionreactionsof2,3-dihydro-1,5-benzothiazepinesand2,3-dihydro-1H-1,5-benzodiazepinewithbenzonitrileN-phenylimineandbenzonitrileoxides,respectively.Theconformationsofsomecycloadductsandcycloadditionmechanismaredescribed.
简介:ThispaperreportsasimpleandhighlyselectivemethodforpreconcentratingandseparatingoftracePd(II)andPt(IV)withsilicagelbondedbyaminopropyl-benzoylazo-4-(2-pyridy-lazo)-resorcinol(ABPR-SG).ABPR-SGisstableinsolutionfrom6mol/LHCltopH7.0andincommonorganicsolvents.ThemaximumadsorptivecapacityofPd(n)onABPR-SGis362μmol/g.AfterpreconcentrationandseparationbyusingABPR-SGcolumn,Pd(II)andPt(IV)ofμg/Llevelinartificialwatersamplescanbemeasuredreliablybycommonspedrophotometry.ThemaximumconcentrationfactorsofPd(II)andPt(IV)onABPR-SGcolumnare143and125respectively.ThechromatographiccolumnpackedwithABPR-SGcanbereused.Themethodissimpleandefficient.
简介:研制出以固态AgCl-KCl-聚乙烯醇-琼脂混合物为导电凝胶的全固态Ag/AgCl参比电极(AllState-ReferencrElectrode,简写为ASRE)。将ASRE与pH玻璃电极组成电极组,直接电位法测定pH2.00-12.00磷酸盐缓冲溶液的pH值,与以饱和甘汞电极为参比电极(SCE)的测定结果比较,相对误差为-0.8%-+0.8%;与氯离子选择电极组合测定1.00×10^(-1)-1.00×10^(-4)mol/LNaCl的电池电动势ΔE,-lgc(Cl-)与ΔE呈良好的线性关系,斜率为-49.3,与以双盐桥SCE为参比电极时的斜率(-49.9)基本一致,表明ASRE能够代替双盐桥SCE运用于Cl-浓度的测定。在10-80℃范围内,以KNO_3溶液(1.000mol/L)为模型,测定ASRE相对于SCE的ΔE,ΔE与T呈线性关系,温度系数为0.123mV/℃。ASRE有望代替传统参比电极,应用于离线或在线电化学测定中。
简介:以恒电位法在pH=9.0碱性水溶液中碳纤维簇电极上镀单层锌,在含有组氨酸和电解氧化锌镀层下原位合成了锌-组氨酸-羟基络合物修饰碳纤维电极,模拟了生物酶识别痕量的硫氢酸根离子,优化了电极制备的条件。建立了开路电位测定硫氢酸根离子的方法,在中性水溶液中,该电极以开路电位变化响应注入溶液中的硫离子浓度,并可用能斯特方程描述开路电位变化的规律。方法的最低检出限为1.0×10μmol/L,检测范围为1.0×10~1.0×10-18mol/L,相对标准偏差为3.5%。对实际样品中硫氢酸根离子检测结果为1.12×10-13mol/L,加标回收率为109.2%。研制的电化学传感器具有响应快速,灵敏度高,检出限低,检测范围宽,仪器简单方便等特点。
简介:水热条件下合成了一种新的锰-乙二胺[Mn(en)]修饰的夹心型锑钨酸盐配位化合物(enH2)3H2{[Mn(en)(H2O)]2(WO2)2(β-B-SbW9O(33))2}·3H2O.通过X-射线单晶衍射方法确定了其晶体结构,结构分析表明该化合物为单斜晶系,P21/c空间群,晶胞参数a=1.32268(18)nm,b=1.8345(2)nm,c=2.21755(19)nm,α=90°,β=126.617(5)°,γ=90°,V=4.318.8(8)nm3,Z=2.通过元素分析,红外光谱及紫外光谱等对其结构进行了表征.电化学循环伏安测试表明该化合物修饰的碳糊电极对H2O2具有显著的电催化还原活性.