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.
简介:Thenon-isothermaldecompositionoflead2,4,6-trinitroresorcinatemonohydrate,Pb(TNR)·H2O,wasinvestigatedbymeansofTG-DTA,DSCandIR.Thethermaldecompositionmechanismandthedissociatedkineticswerealsoinvestigated.ThekineticparameterswereobtainedfromtheanalysisoftheDSCcurvesbyintegralanddifferentialmethods.ThemostprobablekineticmodelfunctionofthedehydrationreactionofPb(TNR)·H2Owassuggestedbythecomparisonofthekineticparameters.
简介:
简介:Inthisletter,Fe2O3UFP(UltrafineParticles)hydrosolandorganosolwithhighthirdorderopticalnonlinearsusceptibility(3)havebeenreportedforthefirsttime.ThesurfacialmodificationofFe2O3UFPwithdodecylbenzenesulfonateions(DBS)canenhancethenonlinearopticalresponsethroughinterfacialconfinementofelectronmotion.Theinvolvedmechanismisdiscussed.
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(L2)2(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.
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.
简介:给出了使用GAUSSIAN程序中密度泛函理论方法进行量子化学计算时遇到的一类问题———六氟锗乙烷分子F3Ge—GeF3的基态构型随计算积分精度不同而改变,即GAUSSIAN程序中计算积分精度对计算结果产生重要影响的一个例子.更多还原
简介:Tetrabutylammoniumorpotassiumsaltsoforganometalllicderivativesoflacunarypolyanion(RM)3P2W15O59^n-(RM=CpTi,CpZr,C4H7O2SnorC5H9O2Sn)havebeenpreparedandstructurallycharacterizedbyelementalanalysis,IR,UV-Vis,^1HNMRand^183WNMRspectroscopies.Thetitlecomplexesexhibitantitumoractivityinvitro.
简介:Anovelaciddyeacidwassynthesizedbythecondensationreactionbetweenbromamineacidand2-amino-6-nitrobenzothiazoleanditsanti-UVprotectionpropertieswereevaluated.Theresultsshowedthatsilkdyedwiththisdyehadverygoodultravioletradiationprotectioncapabilityandexcellentdyeingperformance.TheUV-absorptionmechanismofthisdyewasalsodiscussed.
简介:IntroductionIn2O3·Snfilmshavehightransparency(>95%)withinthevisiblespectralregion,lowresistivity(10-2—10-4ohm·cm)atroomtemperatureandsuperiorthermalstability.Thesefilmshavebeenappliedtosolarcells,electronicsandphotoelectronicsfields.Inrecentyears,organometallic-CVDmethodhasemergedasasuccessfulalternatetothephysicalmethodsandgeneralCVDforthegrowthofthesefilms.TheMO-CVDtech-
简介:Using2-bromo-1-methylpyridimiumiodideascarboxylactivatingagent,10ansa-macrolactamswerepreparedconvenientlyfromthecorrespondingseco-precursorw-aminoacidsintheyieldsof78-2%.