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177 个结果
  • 简介:Ourobjectivesweretodevelopanewchemicalmethodforthepolymerizationofpyrrole.CuCl2dissolvedinC2H5OHsolventisprimarilyusedfortheinitiationpolymerizationofpyrrole.ThepolymerswithdifferentyieldandconductivitywereobtainedbyraringtheinitialconcentrationofCu2+.TheinitialconcentrationsofCu2+variedfrom1.2×10-4moleto6.48×10-3moleCu2+with2.16×10-2molepyrrole.Thepolypyrroleobtainedwascharacterizedwithelementalanalyzer,XPS,IRspectroscopy,Four-pointprobeandSEM.

  • 标签: CuCl2-C2H5OH initiation SYSTEM Polymerization of PYRROLE
  • 简介:Thethree-phasesbehaviorinthequaternarystsemofn-dodecylpolyglucosideC12G1.46/1-butanol/cyclohexane/waterhasbeenstudiedat40℃intermsofthevariablesγandδ.Increasingδatconstantγcausesaphaseinversionfromanoil-in-watermicroemulsionincontactwithexcessoil(winsorIor2)toawater-in-oilmicroemulsionincontactwithexcesswater(winsorⅡor2)viaamiddle-phasemicroemulsionincontactwithexcessoilandwater(winsorⅢor3).Bytakingintoaccountthedifferentsolubilitiesofalkylpolyglucosideand1-butanolintheoilphase,thecompositionofthehydrophile-lipophilebalancedinterfacialfilminthemiddleofthethree-phasebodycanbecalculated.Theeffectsofdifferentoilsandaqueousmediaonthephasebehaviorandonthecompositionoftheinterfacialfilmandtheefficiencyforalkylpolyglucosidetomakeequalweightsofwaterandoiltoasinglephasewereinvestigated.Itwasfoundthattheoilmoleculeswithsmallmolecularvolumescanimprovethesolubilizingefficiencyofthesurfactanttoformsingle-phasemicroemulsion.Ininorganicsalt(NaCl)andacid(HCl)solutions,less1-butanolisneededthanthatinalkali(NaOH)solutiontoformmiddle-phasemicroemulsion.

  • 标签: 中间相微乳液 C12G1.46 烷基聚葡糖苷 相图 界面薄膜 表面活性剂
  • 简介:MassYieldDistributionofTargetResiduesfromInteractionofIronwith135MeV/u12CIons¥QinZhi;LiWenxin;ZhaoLin;WenWanx...

  • 标签:
  • 简介:对黑曲霉木聚糖酶同工学性质及圆二色谱(CD)进行了研究.结果表明,黑曲霉木聚糖酶粗液经离心、超滤及SephadexG-75凝胶层析后,分离得到了两个黑曲霉木聚糖酶同工组分XⅠ,XⅡ,其最适反应温度均为45℃~55℃,最佳反应pH值均为4.8~5.5,SDS-PAGE法测得XⅠ,XⅡ的相对分子质量分别为2.2×104和4.0×104.XⅠ与XⅡ的CD光谱表明,XⅠ,XⅡ分别在218和215nm处有最大负峰,说明β-折叠结构是组分XⅠ,XⅡ具有木聚糖酶活性的主要结构,也是它们发挥催化功能的结构基础.

  • 标签: 黑曲霉 组分 木聚糖酶 反应温度 相对分子质量 凝胶层析
  • 简介:Thesingle-shotspiralmagneticresonanceimaging(MRI)techniquewasimplementedandoptimizedonaBrukerBiospec47/30scanner.Thetechniqueincludesthepulsesequenceforgenerationanddetectionofthek-spaceMRIsignal(freeinductiondecay(FID)),andPC-basedprogramsforthedatagridandimagereconstruction.Thetemporalresolutionis70ms(14imagespersecond),whichconsistsofadataacquisitiontimeasshortas13.7ms,aspin-echotimeof13.6msandamagnetizationrecoverytimeof43ms.Thismakesitpossibletotakereal-timeimagesofmovingobjects.Thetechniqueisdemonstratedusingapendulum(tube)filledwithwater.

  • 标签: 磁共振成象 运动物体 高速螺旋扫描回声技术
  • 简介:对TATB及其系列衍生物进行了半经验分子轨道PM3和AM1计算,求得全优化几何构型和电子结构.结果发现各化合物分子中C-NO2键的Wiberg键级(WCN)均小于其他C-N或C-C键的键级.实验撞击感度h50%与WCN计算结果之间分别呈三阶或二阶多项式关系,相关系数r≥0.92.当WCN<0.90时,该值对撞击感度影响甚微,表明属高感度炸药;而当WCN>0.90时,撞击感度与分子中最小的C-NO2键级WCN呈显著的线性关系,WCN增大,撞击感度线性递减,符合判别感度相对大小的"最小键级原理".

  • 标签: TATB 衍生物 撞击感度 C—NO2键级 1 3 5-三氨基-2 4 6三硝基苯 AM1
  • 简介:引入了主算子为n次积分C半群生成元的线性非齐次抽象柯西问题强解的概念,讨论了相应抽象柯西问题存在强解的一些充分必要条件及强解的表示式,并给出了一个例子验证结果。

  • 标签: N次积分C半群 抽象柯西问题 强解
  • 简介:WereportonN-dopedp-typeZnOfilmswiththec-axisparalleltothesubstrate.ZnOfilmswerepreparedonana-Al2O3(0001)substratebysolid-sourcechemicalvapourdeposition(CVD),Zn(CH3COO)2.2H2OwasusedastheprecursorandCH3COONH4asthenitrogensource.Thegrowthtemperaturewasvariedfrom300℃to600℃,theas-grownZnOfilmdepositedat500℃showedp-typeconductionwithitsresistivityof42Ωcm,carrierdensity3.7×10^17cm^-3andHallmobility1.26cm^2V^-1.s^-1atroomtemperature,whicharethebestpropertiesforp-typeZnOdepositedbyCVD.Thep-typeZnOfilmpossessesatransmittanceofabout85%inthevisibleregionandabandgapof3.21eVatroomtemperature.

  • 标签: ZNO薄膜 固体源 化学蒸汽沉积
  • 简介:Thetitlecomplexi-C4H9Co(salen)(Py)(Py=pyridine.salen=dianionofdisalicylideneethylenediamine)hasbeenfirstsynthesized.ItscrystalstructurehasbeendeterminedbyX-raydiffractionmethod.ThecrystsisaremonoclinicwithspacegroupP21/C.Theunitcellparametesarepresented.ThestructurehasbeenrefinedtoafinalRof0.038.

  • 标签: refined PYRIDINE MONOCLINIC compl alkyl DALTON
  • 简介:定义在C^n中具有逐块光滑边界的有界域上光滑函数的一种积分表示,这种积分表示的特点是积分式中含有局部的全纯核,且含有可供任意选择的实参数p,2≤p<+∝,利用这个公式,我们可获得有界域上-↑a-方程的局部解和证明在含参数局部意义下存在一致估计。

  • 标签: 有界域 局部全纯核 光滑函数 一致估计 Bochner-Martinelli公式
  • 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:theAlternatingSegmentCrank-Nicolsonschemeforone-dimensionaldiffusionequationhasbeendevelopedin[1],andtheAlternatingBlockCrank-Nicolsonmethodfortwo-dimensionalproblemin[2].Themethodshavetheadvantagesofparallelcomputing,stabilityandgoodaccuracy.Inthispaperforthetwo-dimensionaldiffusionequation,thenetregionisdividedintobands,aspecialkindofblock.ThismethodiscalledthealternatingBandCrank-Nicolsonmethod.

  • 标签: 二维空间 分布函数 有限微分方程 边界条件
  • 简介:设节点数据{xj,yj}nj=0来自函数y=f(x),Pn+k(x)为满足插值条件Pn+k(xj)=yj,(j=0,1,…,n)的n+k次多项式插值,In(x)为分段线性插值多项式.本文在范数‖Pn(x)-f(x)‖2或‖Pn(x)-In(x)‖2意义下得出了一种最佳平方逼近的Cn+k次多项式插值P*n+k(x),并且证明了P*n+k(x)的存在唯一性及其相关性质.实践表明该方法有效地抑制了Runge现象的产生.

  • 标签: 多项式插值 振荡现象 误差 最佳平方逼近 插值多项式 Runge现象
  • 简介:P.N.Dowling和C.J.Lennard证明了含渐近等距于l1子空间的Banach空间不具有不动点性质.本文以对偶形式给出了Banach空间合渐近等距于l1或0子空间的充分必要条件,并证明了当一个Banach空间含有渐近等距于l∞子空间时它必含有渐近等于l1子空间.

  • 标签: 非扩张映射 不动点性质 渐近等距 对偶空间
  • 简介:分别用半经验的AM1,PM3及MNDO方法研究了富勒烯衍生物C70S的12种可能异构体的结构和稳定性.计算结果表明:S原子加成在4种6-6键上的稳定构型中,非赤道带6-6键加成的三个异构体为闭环结构,赤道带6-6键加成的一个异构体为开环结构;S原子加成在4种6-5键上均可产生开环和闭环两种稳定构型.加成在6-5双键的异构体其闭环构型更稳定,加成在6-5单键的异构体其开环构型更稳定.闭环异构体中S原子加成在碳球极处6-6键上的构型1,2最稳定,开环异构体中S原子加成在赤道带6-6键上的构型8最稳定.

  • 标签: C70S 异构体 结构 稳定性 理论研究 AML
  • 简介:ThisisoneoftheapplicationsofPart(Ⅰ),inwhichtheangularstiffness,thelateralstiffnessandthecorrespondingstressdistributionsofC-shapedbellowswerecalculated.Thebellowswasdividedintoprotrudingsectionsandconcavesectionsfortheuseofthegeneralsolution(Ⅰ),butthecontinuityofthestressresultantsandthedeformationsateachjointofthesectionswereentirelysatisfied.Thepresentresultswerecomparedwiththoseoftheothertheoriesandexperiments,andarealsotestedbythenumericallyintegralmethod.Itisshownthatthegoverningequationandthegeneralsolution(I)areveryeffective.

  • 标签: theory of flexible SHELL CIRCULAR RING
  • 简介:Thecrystalandmolecularstructuresof[(C3H7O)2PS2]2(CCDCNo.217201)weredeterminedbymeansofX-raycrystallography.ItcrystallizedinatriclinicsystemwithspacegroupP1^-andlatticeparametersa=0.82794(3)nm,b=0.84764(2)nm,c=0.85034(3)nm,α=97.78(3)°β=110.77(3)°,γ=94.95(3)°,V=0.54701(9)nm^3,Z=1.Inthismolecule,thetwodiisopropyldithiophosphategroups,[(C3H7O)2PS2]2,whichareparalleltoeachother,arelinkedbyanS--Sbondandthereexistinversioncentersinthemolecule,Inthestructure,theP=Sbondsinthetwodithiophosphateunitsaretrans-orientedtoeachother.

  • 标签: X射线结晶学 二烃基二硫代磷酸盐 中心对称 2 晶体结构 O'-二异丙基二硫代磷酸盐
  • 简介:Theoptimalconditionsforthecomplexationreactionofmeso-tetra(3-methoxy-4-hy-droxyphenyl)porphineT(3-M-4HP)Pwithplatinumandrhodiumarepresented.Beer’sLawisobeyedwhentheconcentrationofrhodiumisintherangeof0.45-1.15μg/25mL.Themolarabsorptivityofrhodiumwasfoundtobe1.99×106L·mol-1·cm-1at460nm.ThevalueofεPtwasfoundtobe6.28×105L·mol-1·cm-1bylinearregressionmethod.TheKcoefficientmethodandcompensatingcoefficientwereusedtodetermineplatinumandrhodiumsimultaneoulywithoutremovalormaskingoftheinterferentsinthesample.Theresultsforthedeterminationofplatinumandrhodiuminthemixedsolutionofplatinumandrhodiumaresatisfactory.

  • 标签: PLATINUM RHODIUM Spectrophotonletry Meso-tetra(3-M-4HP)P.
  • 简介:<正>Foranyintegersa1,a2,a3,a4andcwitha1a2a3a40(modp),thispapershowsthatthereexistsasolutionX=(x1,x2,x3,x4)∈Z4ofthecongruencea1x12+a2x22+a3x32+a4x42≡c(modp)suchthat‖X‖=max{|x1|,|x2|,|x3|,|x4|}《p1/2logp.

  • 标签: CHARACTER SUMS CONGRUENCES
  • 简介:ThehydrolysisofcephanoneinTritonX-100micelleandTritonX-100/n-C5H11OH/H2O(O/W)microemulsionwerestudiedbymeansofUV-Visabsorptionspectroscopy.Theresultsshowthatcomparedwithwater,TritonX-100micelleandTritonX-100/n-C5H11OH/H2O(O/W)microemulsioncaninhibitthehydrolysisofcephanone.TheinhibitioneffectsofTritonX-100micelleandTritonX-100/n-C5H11OH/H2O(O/W)microemulsiononthehydrolysisofcephanonearerelatedtothelocationofcephanoneintheinterphasesofTritonX-100micellesandTritonX-100/n-C5H11OH/H2O(O/W)microemulsiondroplets.

  • 标签: 氚核X-100 头孢酮 水解 胶束 油/水微乳液 抑制作用