简介：ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｒｅｃｅｎｔｙｅａｒｓ，Ｌａｎｇｍｕｉｒ－Ｂｌｏｄｇｅｔ（ＬＢ）ｆｉｌｍｓｈａｖｅａｔｒａｃｔｅｄｍｕｃｈａｔｅｎｔｉｏｎｂｅｃａｕｓｅｏｆｔｈｅｉｒｐｏｓｉｂｉｌｉｔｉｅｓａｓｆｕｎｃｔｉｏｎａｌｍｏｌｅｃｕｌａｒｄｅｖ...

简介：Afacileandconvenientsynthesismethodhasbeendevelopedforsubstitutedquinoxalinesand2H-benzo[b][1,4]oxazinesfromthereactionsofα-bromoketoneswithbenzene-1,2-diamineand2-aminophenol,respectively,whichwerecatalyzedbytetrabutylammoniumbromide(TBAB)inaqueousbasicmedia.

简介：DensityFunetionalTheory(DFT)methodwasusedinthispapertostudyone-carbontransferfrom1.10-tetrahydroquinoxalinc,ananalogucoftetrahydrofolicaeid,tomethylamine.Thisreaetioncanbecompletedviatwopaths.Fromthecomputationresultwecanconcludethaiageneral-aeidcatalysisexistsinthisreaction.BycomputationwefindDFThasitslimitationindeseribinganewlyincorporatedstructurewithaunitcharge.

简介：Anon-linearoptical(NLO)materialwassynthesizedbymeansofasimplemethod.Thismaterialcanbeappliedinelectro-optical(EO)devices,suchasEOswitchesandmodulators.TheDisperseRed1(DR1)wasdopedinpolymethyl-methacrylate-co-glycidylmethacrylate(PMMA-co-GMA)astheNLOactivechromophore.Thesynthesisprocessandmaterialstructurewereexpressed.Thethermalproperties,surfacemorphologyandopticalcharacteristicsofthematerialwereinvestigatedbymeansofdifferentialscanningcalorimetry(DSC),thermogravimetricanalysis(TGA),atomicforcemicroscopy(AFM),andm-linestechnique.Usingthereflectiontechnique,thevalueoftheelectro-opticalcoefficientγ33wasmeasuredas11pm/Vatawavelengthof1310nm.AnEOswitchwithnanosecondresponsebasedonthismaterialhasbeenfabricated.

简介：Ferron逐时比色法中Al-Ferron体系反应动力学常被视为准一级反应,由此可推得相应的拟合方程并测得相应的反应速率常数kb,显色剂Ferron作为反应物之一其用量必然直接影响测量的结果。以不同OH/Al比的聚合氯化铝溶液为研究对象,抓住Ferron浓度这一核心要素,对Al-Ferron体系反应动力学过程进行了系统研究。结果表明,[Ferron]≥2.0×10^-3mol/L是确保动力学速率常数kb准确测量的基本保证。

简介：DeoxybaccatinⅥ(4α,7β,9α,10β,13α-penta-acetoxy-2α-benzoyloxy-5β,20-epoxytax-11-ene)wasisolatedfromtherootsofTaxuschinensis,Rehd.var.mairei.Thestructuralassignmentsofthecompoundwerebasedontheirspectraldata,including2DNMRexperimentsandchemicalcorrelation.TheX-raycrystallographicanalysisof1-deoxybaccatinⅥprovidedunambiguouscharacterizationforthestructures.Inthestructure,thesix-memberedAringexhibitsboatconformation,theeight-memberedBringadoptsboat-chairconformation,andthesix-memberedCringexhibitsasofaconformation.

简介：WiththedecreaseofpHvaluefrom8.45to–1.0,theUV-Visabsorptionandfluorescentspectraof1,2-bis(4-pyridyl)ethylene(BPE)tookonthesamechangingtrendatfourdifferentsuccessivepHstages:8.45―7.20,7.20―5.62,5.62―2.60,and2.60―-1.0,namely,nochange,decrease,increase,anddecreaseagain.Amongthese,inarangeof7.20―5.62,thefluorescencewavelengthblueshiftedfrom418to359nm,buttheUV-Visabsorptionwavelength,incontrast,redshiftedfrom285to298nm.ThefluorescenceintensityofBPEhadadropeventoquenchuponadeclineinthepHvaluefrom2.60to–1.0probablyowingtoitscation-πinteractiontoreducetheπelectronclouddensityofBPE.Twodissociationconstants,pKa1(4.30±0.01)andpKa2(5.65±0.04),wereobtainedbasedonfluorescencedata.ThechangesoffluorescencespectraindicatethatBPEhas'off-on-off'switchbehavior.ThefluorescentspectraofBPEwerenearlyindependentonthepresenceofα-andβ-cyclodextrins.

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

简介：Nitricoxidehasplayedanimportantroleinmanyphysiologicalandpathologicalprocessesasakindofimportantgassignalmolecules.Inthiswork,anewfluorescentprobeLysoNO-NaphfordetectingNOinlysosomesbasedon1,8-naphthalimidewasreported.LysoNO-Naphhassub-groupsofo-phenylenediamineasaNOreactionsiteand4-(2-aminoethyl)-morpholineasalysosome-targetablegroup.Thisprobeexhibitedgoodselectivityandhighsensitivity(4.57mmol/L)towardNOinawidepHrangefrom4to12.Furthermore,LysoNO-NaphcanbeusedforimagingNOinlysosomesinlivingcells.

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

简介：Thesynthesisofanewtypeofhetero-macrocyclicpolyether2,3-henzo-1,4,7,13-tetraoxa-10-selenacyclopentadeca-2-eneisdeseribed.

简介：2,2’-二（1,1’-4-甲基-吡啶）联咪唑（L）、芳香二羧酸与乙酸镉在水热条件下反应得到了配位聚合物[Cd2（L）（p-bdc）2（H2O）2]n（1）和[Cd（L）0.5（m-bdc）]n（2）,并用单晶衍射仪定义了其晶体结构.结构分析表明,配合物1结晶属于正交晶系,Ibca空间群,配合物2结晶属于单斜晶系,C2/c空间群,进一步分析表明,所合成的2个化合物都是有扭曲α-Po拓扑的三维网络结构.在室温条件下,配体L和2个配合物均表现出较好的荧光性质.

简介：标题化合物（C24H16N4S）以噻吩-2-甲醛、苯甲酰乙腈和3-甲基-1-苯基-1H-吡唑-5-胺为原料,在离子液体[bmim]Br溶剂中,在80℃搅拌合成得到.其结构通过单晶X射线衍射法确定,晶体属于三斜晶系,空间群P-1,相对分子质量Mr=392.47,晶胞参数a=0.93612（8）nm,b=1.03063（12）nm,c=1.16624（16）nm,V=0.96853（19）nm3,Z=2,晶胞密度Dc=1.346g/cm3,吸收系数μ=0.185mm-1,单胞中电子的数目F（000）=408.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子R=0.0585,wR=0.1337.在晶体结构中新形成的吡啶环与吡唑环近似于共平面结构.

简介：通过硝酸、氢氟酸和盐酸分解试料,高氯酸冒烟驱走硅和氟,最后用盐酸溶解盐类,应用电感耦合等离子体原子发射光谱法（ICP-AES）对高效复合孕育剂中铝、钙、钡进行测定,方法能准确、快速地测定其含量,加标回收率在98.8%~103%,精密度、标准样品分析对照均取得了满意的结果。

简介：建立了提取和清洗整合成一步的超声辅助-固相分散溶液提取离子色谱法测定染发剂中的9种染料中间体的方法。样品基质经分散后，测定组分进入溶液，油脂溶解在正已烷中，干扰化合物被分散剂吸附。在振荡、超声和加热的协同作用下，9min内快速完成提取，具有高的样品处理效率。用离子色谱法测定商业染发剂中的中间体以确定方法的提取效率。方法的线性范围为0.2-100mg/L，检出限0.019-0.048mg/L，回收率85.0%-107.0%，相对标准偏差0.30%-3.7%。实验结果表明，方法简单、可靠，适用于大批量样品的常规分析。

简介：Asimpleandefficientmethodhasbeendeveloped;benzil/benzoinundergoessmoothcondensationwithvarioussubstitutedaldehydeandammoniumacetateinthepresenceofpotassiumdihydrogenphosphate(KH_2PO_4)undermildreactionconditionstoaffordthecorrespondingtrisubstitutedimidazoleinexcellentyields.Themethodforsynthesisofproduct,thereactionmixturewasrefluxinethanolfor40-90min.Thepresentmethodissimple,efficient,andcost-effective.

简介：采用表面等离子共振（SPR）生物传感器，分别固定Aβ及其单克隆抗体于传感芯片表面，实时监测Aβ与Cu（Ⅱ）混合前后与Aβ单抗体特异的结合过程，及Cu（Ⅱ）与Aβ亲和结合及解离情况．结果显示：Cu（Ⅱ）影响Aβ与Aβ单抗体的特异结合能力，加入Ca（Ⅱ）后Aβ不能与Aβ单抗体起特异免疫结合反应；Aβ与Cu（Ⅱ）的结合过程为快结合快解离的动力学过程．

简介：Basedonthestructure-activityrelationshipsofRGD-containingpeptides,aseriesof1,3-dihydro-l,3-dioxo-2H-isoindolederivativesweresynthesized.Allofthemwerefirstreported.Theirstructureswereconfirmedbyspectraldataandelementalanalysis.Theirabilitytoinhibitangiogenesiswereevaluatedinthechickembryochorioallantoicmembraneassayat-10^-5mol/L.Compounds5band5edisplayedobviouslyantiangiogenicactivity.

简介：运用电化学循环伏安和石英晶体微天平研究了1,4-丁二醇(1,4-BDL)在Pt电极及以Sb和S吸附原子修饰的Pt(Pt/Sbad和Pt/Sad)电极上的吸附和氧化过程.结果表明,1,4-丁二醇的氧化与电极表面氧物种有着极其密切的关系,表面质量变化提供了吸附原子电催化作用的新数据.Pt电极表面Sb吸附原子能在较低的电位下吸附氧,可显著提高1,4-丁二醇电催化氧化活性.与Pt电极相比,1,4-丁二醇在饱和吸附Sb原子的Pt电极上氧化的峰电位负移了0.20V,峰电流增加了1.5倍.相反,Pt电极表面S吸附原子的氧化会消耗表面氧物种,饱和吸附的S原子抑制了1,4-丁二醇的氧化.