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500 个结果
  • 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:TheinfluencesofboththevolumeofPS/toluenesolutionintheUbbelohdeviscometerandtheprecisionofthetimemeasuringontheviscositybehaviorindiluteandextremelydiluteconcentrationregionareinvestigatedItwasfoundthattheinfluenceoftheformercanneglect,butthatofthelatterissoprominentthatthedatafluctuatebitterlyandlinearityofthecurveofthereducedviscosityvs.Concentration(ηsp/c~c)becomestoobadtoobeytheHugginsequationdowntotheextremelydiluteregion,despitetheerroroftheflowtimes△t≤0.2s,whichispermittedbytheconventionalmethodofviscositymeasurement.Throughstrictmathematicalanalyses,itwasfoundthatthcerror(E)ofthereducedviscosityisinproportionandinverseproportionto△tandconcentrationc,respectively.Sothelesstheconcentration,themoretheerroris.Consequently,alowestconcentrationlimitcLcorrespondingtogivenexperimentalerrormayexistanditwillbemeaninglessforfurtheroperationbelowcLbecauseofthegreatfluctuationofthedata.Therefore,itneedstoseriouslyreconsidertheapplicationoftheconventionalmethodofUbbelohdeviscositymeasurementintheextremelydilutepolymersolutionundertraditionalconditionsbecauseofthegreatinfluenceoftheexperimentalerror.

  • 标签: 粘性 聚苯乙烯/甲苯溶液 实验误差 粘度计 稀释溶液 物理性质
  • 简介:ThelasersystemPALS,asadriverofabroad-beamionsource,delivereddeuteronswhichgeneratedneutronswithenergieshigherthan14MeVthroughthe7Li(d,n)8Bereaction.Deuteronswithsub-MeVenergywereacceleratedfromthefrontsurfaceofamassiveCD2targetinthebackwarddirectionwithrespecttothelaserbeamvector.Simultaneously,neutronswereemittedfromtheprimaryCD2targetandasecondaryLiFcatcher.Thetotalmaximummeasuredneutronyieldfrom2D(d,n)3He,7Li(d,n)8Be,12C(d,n)13Nreactionswas~3.5(±0.5)×108neutrons/shot.

  • 标签: beam–target fusion DEUTERONS laser ion SOURCES
  • 简介:AseriesofPS-PPACwasdevelopedandthepositionresolutionwassuccessivelyimprovedbyusinordertomeettheneedofheavyionphysicsresearch.ThePS-PPACmaybedividedintotwogroups.1PS-PPACusedforstable(ion)bearna)Doublegridpositionsensitiveavalanchechamber(DGAC)~[1].DGACconsistsof4electrodes:anodeA,cathodeC,gridsKandG,whicharemadeofwireplanes.Thesensitiveareawas25×20cm~2.Aposition

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  • 简介:这篇文章介绍一条灵巧的途径给聚苯乙烯/银(PS/Ag)的准备不对称的混合粒子。在这个方法,polystyrene/polyglycidylmethacrylate(PS/PGMA)Janus粒子经由dichloromethane(DCM)的蒸发从PS/PGMA/DCM-in水乳剂微滴触发的内部阶段分离被综合。然后,Janus粒子是aminated并且顺序获得PS/PGMA-NH2PS/PGMA-COOH粒子的carboxylated。在由与amine/carboxyl协调的functionalizedPS/PGMA粒子的PGMA半球的表面上自我装配的Ag+。有Ag的7.29wt%的PS/Ag不对称的混合粒子被Ag+的减小获得。扫描电子显微镜学,精力散的X光检查光谱学和传播电子显微镜学结果证实Ag在聚合物粒子的表面上是不均匀地分布式的。

  • 标签: 不对称分布 混合颗粒 自组装 相分离 PS 合成
  • 简介:我们介绍自发的对称碎在Pati之间的acouplingbetween的顺序—Salam和电镀物品弱对称苏(4)_(PS)直接X苏(4)_(EW)可伸缩以便在宏大统一精力在联合常数之中建立一种算术地一致的关系。与减已知的夸克和雷普顿的雷普顿量数字那里的酒吧的价值,由传递includingright的中微子,我们能在直到电磁的U(1)_(他们)的层次放大的不同精力发现混合角度关系。

  • 标签: 电弱模型 统一化对称 规范对称 耦合常数
  • 简介:Inthispaper,twokindsofPS-PTCsweresynthesizedusingdifferentmethodsbyintroducingcinchonineandquininetothepolymersupport.TheircatalyticpropertiesforthealkylationofN-diphenylmethyleneglycinet-butylesterwerealsocompared.

  • 标签: 聚合物 催化剂 非对称相变
  • 简介:Thehybridstructuresofpolystyrene-b-poly(ethyleneoxide)(PS-b-PEO)blockcopolymerandinorganicnanoparticleswithgoodstabilityandbiocompatibilityhavepotentialapplicationsindrugdeliveryandbioimaging.Sphericalco-assembliesofPS120-b-PEO318andoleylamine-cappedCdSquantumdots(QDs)areproducedsuccessfullyinthisworkbyaddingwatertoamixedcommonsolvent,suchasN,N-dimethylmethanamide(DMF)/chloroform,DMF/tetrahydrofuran(THF),orDMF/toluene.TheenergydispersiveX-ray(EDX)spectrumindicatesthatQDsarelocatedattheinterfacebetweenthecoreandshellofthesphericalco-assemblies.Theco-assemblyprocessduringwateradditionistracedbytransmissionelectronmicroscopy(TEM)andturbiditymeasurement.Sphericalco-assembliesareformedthroughbuddingfrombilayersoftheblockcopolymerandQDs.Themorphologyoftheco-assembliesisrelatedtothemiscibilityoftheQD-dispersingsolventswithwaterandthemorphologychangesfromasphericaltoavesicle-likestructurewithDMF/toluene.IncreasingTHFcontentinthemixedsolventcausesmorphologicaltransitionsfromsphericalco-assembliestomulti-branchedcylindersandmicelleswhereQDsarelocatedinthecentralcore.Increasingchloroformcontentyieldsvesicle-likestructureswithprotrudingrodsonthesurface.Themechanismofthemorphologicaltransitionsisalsodiscussedindetail.

  • 标签: Co-assembly Mixed common solvent PS-B-PEO Solvent composition
  • 简介:<正>(a1/2)2和(a2)1/2兄妹俩,一来到花果山就受到众猴儿的青睐,争相和他俩交朋友,哪知有的小猴对他俩不礼貌,有时还受到了委屈,于是他俩就到猴王那里去告状,兄妹俩来到猴王面前,深深行了个鞠躬礼说:“报告猴王,小猴儿常把我俩张冠李戴,用我俩来解题时,

  • 标签: 算术平方根 非负数 花果山 二次根式 彻底认识 彻底了解
  • 简介:嵌段共聚物聚苯乙烯-b-聚氧化乙烯(PS-b-PEO)甲苯溶液在室温下陈化2个月可形成中间是PEO单晶上下表面为PS具有"三明治"结构的方形片层,并且既能形成单层方形片层,也能形成多层方形片层.采用透射电子显微镜手段观察了这种结构在不同水含量的水/甲苯混合溶剂蒸汽诱导后形成的结构形貌.结果证明在甲苯和水蒸汽中,方形片层结构均能稳定存在,不能进行结构重构;而随着混合蒸汽中水含量的增加,单晶溶解、消失,在甲苯和水的共同作用下,可通过结构重构形成新的垂直或平行于表面的柱状相结构.

  • 标签: PS-b-PEO嵌段共聚物 方形片层结构 溶剂诱导 结构重构
  • 简介:Twonewdicyanamidecoordinationpolymers,{Mn(dmpz)[N(CN)2]2}2(1)and{Cu(dmpz)[N(CN)2]2}2(2)(dmpz=3,5-dimethylpyrazole),weresynthesizedandcharacterizedbysinglecrystalX-raydiffractionanalysisandIRspectroscopy.In1and2themetalionshavetwodifferentcoordinationmodes,whereoneiscoordinatedtofourdicyanamideanionsandtwomonodentatedmpzmoleculestoformaslightlydistortedoctahedralgeometry,whiletheotheradoptsoctahedralgeometry,surroundedbyfournitrileNatomsandtwoamideNatomsofthedicyanamideanions.Bothcomplexescontaintwoalternatingchainsthatareparalleltoeachother.

  • 标签: 氰氨基化合物 聚合体 晶体结构 3 5-二甲基吡唑
  • 简介:分析了动态对等群组密钥管理协议的研究最新的研究成果,提出一能满足动态对等群组密钥管理需求的改进TGBH协议。通过与原有的TGBH协能进行的性能对比分析表明,所提出的协议有效地降低了通信和存储方面的负载。

  • 标签: 组播 群组通信 密钥管理 动态对等群组 TGBH协议
  • 简介:Hypersubstitutions是印射操作符号到相应arities的术语的地图砰。他们作为使ahyperidentity和归纳的概念精确到M-hyperidentities的一个方法被介绍。每身份作为亢奋的身份在满足的一个变化被称为固体。如果每身份是为子集Mof的M-hyperidentity所有亢奋的替换的集合,变化被称为M固体。在亢奋的替换的单音的标志和一种给定的类型的代数学的所有变化的格子的潜水艇格子之间有一个Galois连接。因此,知道怎么有趣、有用半组或在到M固体变化的相应格子的性质的这个Galois连接下面的亢奋的替换转移的单音的标志性质ofmonoids。在这篇论文,我们学习类型(2,2)的eachhypersubsfitution的顺序,即,周期的subsemigroup的顺序由类型的所有亢奋的替换的单音的标志的thathypersubstitution产生了(22)。主要结果是顺序是1,2,3,4或无限。

  • 标签: 超代换 半群 (2 2)类
  • 简介:ThesplittingofpotentialenergylevelsforgroundstateX2ΠgofOx2(x=+1,1)underspin–orbitcoupling(SOC)hasbeencalculatedbyusingthespin–orbit(SO)multi-configurationquasi-degenerateperturbationtheory(SO-MCQDPT).TheirMurrell–Sorbie(M–S)potentialfunctionsaregained,andthenthespectroscopicconstantsforelectronicstates2Π1/2and2Π3/2arederivedfromtheM–Sfunction.TheverticalexcitationenergiesforOx2(x=+1,1)areν[O+12(2Π3/2→X2Π1/2)]=195.652cm1,andν[O12(2Π1/2→X2Π3/2)]=182.568cm1,respectively.Allthespectroscopicdataforelectronicstates2Π1/2and2Π3/2aregivenforthefirsttime.

  • 标签: 分子结构 势能函数 自旋轨道耦合 电子态
  • 简介:<正>我们通常通过"数形结合"的方法判断过定点的直线与双曲线x2/a2-y2/b2=1能否相切,强调对图形的感知能力。本文拟用严格的代数方法说明定点与双曲线的位置关系对切线条数及切点位置的影响。

  • 标签: x~2/a~2 y~2/b~2 数形结合 代数方法 平面直角坐标系 恒成立
  • 简介:ThecrystalstructureofDi-nitratobis(ethylcaprolactam)uranyl(Ⅱ)UO2[CH2(CH2)4CONC2H5]2(NO3)2wasestablishedbyasingle-crystalX-raydiffractionstudy.Itistriclinie,spacegroupP1,witha=7.171(2),b=8.655(3),c=10.182(5)A,α=78.27(3),β=70.63(3),γ=81.76(3)°,V=581.7(4)A3,Z=l,Dc=1.94g.cm-3.FinalRvalueis0.0218.Theresultrevealsthaturanylioniscoordinatedtosixoxygenatoms,twoofthemarefromtwocarbonylgroupsofethylcaprolactamandtheotherfourarefromtwonitrategroups.

  • 标签: carbonyl coordinated nitrate NITRATOBIS NO3 ONC2H5
  • 简介:Inthispaper,westudytheperturbationofspectrafor2×2operatormatricessuchasMX=(AX0B)andMZ=(ACZB)ontheHilbertspaceH⊕Kandthesets∩X∈B(K,H)Pσ(MX),∩X∈B(K,H)Rσ(MX)and∩Z∈B(H,K)σ(MZ),∩Z∈B(H,K)Pσ(MZ),∩Z∈B(H,K)Rσ(MZ),∩Z∈B(H,K)Cσ(MZ),whereR(C)isaclosedsubspace,arecharacterized

  • 标签: 算子矩阵 扰动 希尔伯特空间