学科分类
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406 个结果
  • 简介:Anefficientsyntheticmethodwasdevelopedtosynthesize2-substitutedbenzimidazolesandbenzo-xazoleswithβ-ketoestersasstartingmaterialsundermildreactionconditions,duringwhichotherfunctionalgroupsarebearablefromreactantstoproducts.

  • 标签: 取代苯并咪唑 高效合成 合成方法 反应条件
  • 简介:Theaggregationbehaviorandstructureofhydrophobicallymodifiedblockcopolymersofacrylamideand2-phenoxylethylacrylatewereinvestigatedbyviscometry,1HNMRrelaxation,2DNOESY,fluorescenceanddynamiclightscattering.Itwasfoundthattheaggregationbehaviorwasstronglydependentontheconcentrationofpolymersolutionandthehydrophobecontents.Withvaryingconcentrationfrom2.0,6.0,8.0to12.0g/L,thereweredifferentaggregatemorphologiesdistributedinaqueoussolutions,suchasmonopolymerchain,micelle-likeaggregate,multi-micelleaggregateandcross-linkednetwork.Accordingtothemodelofaggregation,itcangiveareasonableexplanationonthelargemagnitudeenhancementofviscositywiththeincreasingofpolymerconcentration.Additionaldataof2DNOESYandfluorescenceshowthatthecopolymerwithhigherhydrophobecontent(molarfraction≥1%)islikelytoformintra-molecularassociation.

  • 标签: 疏水改性聚丙烯酰胺 聚集行为 结构 嵌段共聚物 NOESY 聚合物溶液
  • 简介:Thenon-isothermaldecompositionoflead2,4,6-trinitroresorcinatemonohydrate,Pb(TNR)·H2O,wasinvestigatedbymeansofTG-DTA,DSCandIR.Thethermaldecompositionmechanismandthedissociatedkineticswerealsoinvestigated.ThekineticparameterswereobtainedfromtheanalysisoftheDSCcurvesbyintegralanddifferentialmethods.ThemostprobablekineticmodelfunctionofthedehydrationreactionofPb(TNR)·H2Owassuggestedbythecomparisonofthekineticparameters.

  • 标签: 热分解动力学 2 4 6-三硝基间苯二酚 铅化合物 一水化物
  • 简介:Inthisletter,Fe2O3UFP(UltrafineParticles)hydrosolandorganosolwithhighthirdorderopticalnonlinearsusceptibility(3)havebeenreportedforthefirsttime.ThesurfacialmodificationofFe2O3UFPwithdodecylbenzenesulfonateions(DBS)canenhancethenonlinearopticalresponsethroughinterfacialconfinementofelectronmotion.Theinvolvedmechanismisdiscussed.

  • 标签: CONFINEMENT INTERFACIAL SUSCEPTIBILITY ULTRAFINE hinder coated
  • 简介:基于刚性配体2-(4-噻唑基)苯并咪唑和二价金属铜离子在水热条件下成功地合成了2个Keggin型多酸化合物[CuⅡ(L1)2(H2O)]2[SiW12O40](1)和[(L1)4(L22(H3PMo12O40)2]·5H2O(2)(L1=2-(4-噻唑基)苯并咪唑,L2=苯并咪唑).通过单晶X-射线、红外光谱和元素分析对化合物1和2进行了表征.在化合物1中,存在2个独立的结构单元:Keggin型多酸和蝴蝶状的络合物阳离子[Cu(L1)2(H2O)]2+.化合物2为含有混合配体的超分子结构,由Keggin型多酸、4个游离的L1和2个L2配体组成.此外,研究了化合物1和2的电化学和光催化性能.

  • 标签: Keggin多酸 2-(4-噻唑基)苯并咪唑 苯并咪唑 电化学 光催化
  • 简介:Novelsulfur-containingcompounds(3a–3c,4a–4c)wereobtainedinethanolwith1,3-diphenyl-2-propanoneasthestartingmaterial.Theadvantagesofthisprocedureweremildreactionconditions,simpleprotocol,andhighyields.ThestructuresoftheproductswerecharacterizedbyIR,1HNMR,MSandelementaryanalysis.Thecrystalofthenewcompound4abelongstomonoclinic,spacegroupC2witha=18.727(3),b=6.5179(9),c=13.7576(18),b=131.0610(10)°,V=1266.2(3)A3,Z=2,Dc=2.136g/cm3,μ=1.078mm-1,F(000)=843,R=0.0490andwR=0.1247for3211observedreflectionwithI>2δ(I).X-rayanalysisrevealsthatthemoleculeisnotsymmetrical,themolecularstructureisstabilizedbyweakp–pstackinginteractions,andnoclassicalhydrogenbondscanbeobserved.

  • 标签: 硫醇 苄基 显示 合成 寺院 结构稳定
  • 简介:以胺甲基苯并咪唑和水杨醛为原料设计合成了一个苯并咪唑衍生物荧光探针,通过荧光分光光度法和紫外分光光度法探寻其对常见阴阳离子的选择性识别性能.研究结果表明,Cu2+对合成得到的苯并咪唑衍生物具有荧光猝灭——“关”的作用,而S2O72-对该荧光猝灭体系具有荧光恢复——“开”的作用.据此,提出了具有实现对Cu2+,S2O72-的荧光“关-开”型探针.

  • 标签: 苯并咪唑衍生物 荧光探针 阴离子 阳离子
  • 简介:Tetrabutylammoniumorpotassiumsaltsoforganometalllicderivativesoflacunarypolyanion(RM)3P2W15O59^n-(RM=CpTi,CpZr,C4H7O2SnorC5H9O2Sn)havebeenpreparedandstructurallycharacterizedbyelementalanalysis,IR,UV-Vis,^1HNMRand^183WNMRspectroscopies.Thetitlecomplexesexhibitantitumoractivityinvitro.

  • 标签: 抗癌抗菌素 抗癌活性 合成 结构 多氧钨酸盐
  • 简介:Anovelaciddyeacidwassynthesizedbythecondensationreactionbetweenbromamineacidand2-amino-6-nitrobenzothiazoleanditsanti-UVprotectionpropertieswereevaluated.Theresultsshowedthatsilkdyedwiththisdyehadverygoodultravioletradiationprotectioncapabilityandexcellentdyeingperformance.TheUV-absorptionmechanismofthisdyewasalsodiscussed.

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  • 简介:借助密度泛函理论,用B3LYP和BP86方法,对一系列潜在的新型高能密度材料分子H2N5MN5H2(M=Be,Mg,Ca,Zn,和Cd)进行了理论预测研究.结果表明,这些材料分子都非常稳定,不容易分解,其中H2N5MN5H2最稳定.金属离子的配位作用对化合物的稳定起了重要作用.配体H2N5也因从金属M获得一个电子变成H2N^-离子而变得更稳定.

  • 标签: 高能密度材料 密度泛函理论 稳定性
  • 简介:IntroductionIn2O3·Snfilmshavehightransparency(>95%)withinthevisiblespectralregion,lowresistivity(10-2—10-4ohm·cm)atroomtemperatureandsuperiorthermalstability.Thesefilmshavebeenappliedtosolarcells,electronicsandphotoelectronicsfields.Inrecentyears,organometallic-CVDmethodhasemergedasasuccessfulalternatetothephysicalmethodsandgeneralCVDforthegrowthofthesefilms.TheMO-CVDtech-

  • 标签: Metallorganic chemical VAPOUR DEPOSITION (MOCVD) Tin
  • 简介:Using2-bromo-1-methylpyridimiumiodideascarboxylactivatingagent,10ansa-macrolactamswerepreparedconvenientlyfromthecorrespondingseco-precursorw-aminoacidsintheyieldsof78-2%.

  • 标签: LACTAM ansa-macrolactam CYCLIZATION lactamization.
  • 简介:10mol%CuIcombinedwiththeDMEDAligandcanefficientlycatalyzetheN-arylationof2-arylindoleswitharyliodidesandarylbromidesingoodtoexcellentyields.Thearylhalidesbearingelectron-richorelectron-deficientfunctionalgroupscanbewelltoleratedunderthismildreactionconditions.

  • 标签: 芳基卤化物 芳基化 催化 芳基碘化物 反应条件
  • 简介:Threepairsofnovel2-aryl-3,4,5-trihydroxypiperidines(6–8andtheirenantiomers),thepiperidineanaloguesofthepyrrolidinealkaloidsradicamineAandradicamineB,werepreparedfromsixmemberedcyclicnitronesthroughaconcisetwo-stepprocedure,i.e.,Grignardreagentadditionanddeprotection.Thesenovelpolyhydroxylatedpiperidineiminosugarswereassayedagainst10typesofenzymes.Onlycompound8exhibitedweakinhibition(IC501080mmol/L)againstb-galactosidasefromratintestinallactases.

  • 标签: 半乳糖苷酶 酶抑制 芳基 合成 格氏试剂 IC50