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500 个结果
  • 简介:A60%Fe/Al2O3catalystwaspreparedbytheco-precipitationmethod.ItwasreducedbyH2toproducemetallicFe,whichwasthensulfidedbyCS2toFe0.96SandFe3S4orphosphidedbytriphenylphosphine(PPh3)inliquidphasestoFe2PandFeP.Itwasfoundthattheironsulfides(Fe0.96SandFe3S4)exhibitedthelowactivityforthehydrodesulfurization(HDS)reactions.TheHDSactivitywasalsolowontheFe(metal)/Al2O3andFe2P/Al2O3catalystssincetheywereconvertedintoFe0.96SandFe3S4duringtheHDSreactions.Incontrast,theFeP/Al2O3wasfoundtobestableandactivefortheHDSreactions.Inparticular,FeP/Al2O3possessedsignificantlysmallerFePparticlesthanFeP/C,leadingtothesignificanthigherHDSactivityofFeP/Al2O3thanFeP/C.

  • 标签: Fe2P/Al2O3 CATALYST FeP/Al2O3 CATALYST Liquid phase
  • 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:RemanspectroscopyisusedasatooltomonitorthereactionbetweenN,N’-di(pmethyl)monothioxamidesand1,3-diaminetrimethyleneandtodetectthereactionintermediate.Byobservingchangesof1024cm-1C=Sbandandappearanceofanewbendataround1720cm-1,thereactionmechanismisdiscussed.

  • 标签: appearance monitor DIAMINE observing FIGURE minutes
  • 简介:TypeIX-rayburstsarethemostfrequentthermonuclearexplosionsinnature,resultingfromthermonuclearrunawayonthesurfaceofanaccretingneutronstar[1].Thebreakoutreaction14O(α ,p)17FfromthehotCNOcyclemayhaveaprominentimpactontheburstlightcurveandburstashes[2].However,insufficientexperimentalinformationisavailabletocalculateareliable,preciserateforthisreaction[3].Weproposedtoaddresstheexperimentalinvestigationofthe14O(α,p)17FusingTimeProjectionChamber(TPC)[4].

  • 标签: PROJECTION SIMULATION GEANT4 experimental surface impact
  • 简介:古典分子的动力学模拟被执行学习高温度(在300K上面)体积水的动态行为,明确地散开系数,氢契约,和近邻居的一生的行为。二个水潜力被比较:最近建议的全球性最佳的点费用(OPC)模特儿和著名TIP4P-Ew当模特儿。由考虑计算反的散开系数和旋转松驰常数的Arrhenius阴谋,到有增加温度的一个线性趋势的从VogelFulcherTammann行为的一条转线路分别地是为OPC和TIP4P-Ew模型的检测atT*309和T*285K。试验性地,转线路点是以前观察的atT*3155K。我们也为热扩大P(T,P),等压的P(T)曲线十字在大约一样的T*是在实验。水氢契约并且最近的邻居的一生被评估并且被发现穿过nearT*,在一生是大约1ps的地方。为TT*,水象简单液体一样更表现。事实那T*在生物学上相关的温度以内的下降变化为biomolecular系统是现象和它的可能的后果的进一步的分析的强壮的动机。

  • 标签: 动力学模拟 动态行为 液体水 高温度 OPC 分子
  • 简介:利用非线性增生映射值域的扰动定理,研究了非线性椭圆边值问题(@)在Ls(Ω),p≤s<+∞中解的存在性.(@){-△pu+g(x,u)=fa.e.在Ω中-∈βr(u(x))a.e.在Γ上其中f∈Ls(Ω),p≤s<+∞给定,ΩRN为有界锥形区域,△pμ=div(|u|p-2u)为P拉普拉斯算子.max(N,2)≤p<+∞,v为Γ的外法向导数,g:Ω×R→R满足Caratheodory条件,对x∈Γ,βx是正常、凸、下半连续函数φx=φ(x,@)的次微分.其中φ:Γ×R→R.本文推广了魏利和何震所讨论的非线性问题的边值条件.

  • 标签: 增生映射 半连续映射 非线性椭圆边值问题
  • 简介:采用共孔径发射和接收技术可使激光信标系统结构紧凑、控制简单。在激光的共孔径发射和接收中使用偏振耦合分光方法有分光效率高、简单可靠等优点。但是,组成地平式折轴望远镜的反射镜对s光和p光的相位延迟有差异,望远镜旋转造成的激光偏振态变化更严重地影响了偏振分光的接收效率。要保持较高的接收效率,就需要对激光相位进行动态补偿。

  • 标签: 相位延迟 分光系统 偏振耦合 反射镜 孔径 测量
  • 简介:利用非线性增生映射值域的扰动定理,研究了非线性椭圆边值问题(1)在Ls(Ω)空间中解的存在性,其中max(N,2)≤p≤s<+∞.(1){-div{(C(x)+|▽u|2)p-2/2▽u}+|u|p-2u+g(x,u(x))=fa.e.x∈Ω-〈n,(C(x)+|▽u|2)p-2/2▽u〉∈βx(u(x))a.e.x∈Γ这里f∈Ls(Ω)给定,Ω()RN为有界锥形区域,n为Γ的外法向导数,g:Ω×R→R满足Caratheodory条件且对()x∈Γ,βx是正常、凸、下半连续函数ψx=ψ(x,·)的次微分,其中ψ:Γ×R→R.本文是对笔者以往一些工作的继续和补充.

  • 标签: 增生映射 demi连续映射 P-LAPLACE算子
  • 简介:SYNTHESIS AND 183W NMR CHARACTERIZATION OF P4W30Al4(H2O)2O11220- HETEROPOLYANIONSYNTHESISAND183WNMRCHARACTERIZ?..

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  • 简介:本文利用等价方程组,友矩阵与Jordan标准型,研究了n阶常系数线性非齐次常微分方程P(D)x=acose^t+bsine^t其中P(D)=D^n+a1D^n-1+…+an,D=1/dt,a1,a2,…a,a,b为任意实常数,在友矩阵具有n个不同的特征根的条件下,给出了求上述方程的特解的方法,最后给出一个详细的实例。

  • 标签: 常系数线性非齐次常微分方程 特解 友矩阵 JORDAN标准形
  • 简介:Theeffectandmechanismofcarmustine(BCNU)combinedwithall-transretinoicacid(ATRA)ontheapoptosisofhumanglioblastomaU251cellswereinvestigatedbymeansof3-(4,5-dimethylthiazol-2-yl)-2,5-diphe-nyltetrazoliumbromide(MTT)assay,flowcytometry,reversetranscription-polymerasechainreaction(RT-PCR)andWesternblotanalysis.TheresultsshowthatBCNUorATRAshowstime-anddose-dependentinhibitioneffectsonhumanglioblastomaU251cellsandthecombinationofBCNUwithATRAshowsansynergisticinhibitioneffectonhumanglioblastomaU251cells,andthecombinedBCNUandATRAcansignificantlyinhibittheproliferationofhumanglioblastomaU251cells,andinducetheapoptosisofthem,makingthecellsarrestinthestageofG1phase,thestageofSandG2phasesdecline,therateoftheapoptosisofhumanglioblastomaU251cellsincrease,thecorrespondingmRNAexpressionofcyclinEandcyclin-dependentkinase2(CDK2)downregulatedandthecorrespon-dingmRNAexpressionofp27kip1unregulated.Inaddition,thecombinedBCNUandATRAreducedtheproteinexpressionofnuclearfactorkappaB(NF-κB).Takentogether,theseresultssuggestthatthetreatmentofhumanglioblastomaU251cellswithacombinationapplicationofATRAandBCNUcanexertsynergisticeffect,thecourseofthiskindofcombinationchemotherapymaylikelybeassociatedwithmultiplemolecularmechanismsforapoptosis,furthermore,thecyclinEandp27kip1shouldbeconsideredasnoveltargetsforcontrollingthegrowthofglioblastomacells.

  • 标签: 全反式维甲酸 脑胶质瘤 细胞凋亡 细胞周期素 卡莫司汀 细胞周期蛋白依赖性激酶
  • 简介:在旅行波浪转变下面,一些非线性的部分微分方程例如Camassa河边肥沃的低地方程,高顺序的KdV方程,等等,被归结为u″表示的一首integrable颂诗+p(u)(u')2+q(u)=0答案能被给其将军。而且,为多项式联合完全的辨别系统,这些方程的所有单个旅行波浪答案的分类被获得。方程u″0包括的+p(u)(u')2+q(u)=是的方程(u')2=f(u)一种特殊情况,建议方法能也因此被用于很多非线性的方程。这些完全的结果不能被任何间接方法获得。

  • 标签: 数学物理方法 非线性数学物理方程 孤波解 对称群 非线性偏微分方程
  • 简介:QuantumdynamicscalculationsforthetitlereactionH(2S)+S2(X3-Σg)→SH(X2Π)+S(3P)areperformedbyusingagloballyaccuratedoublemany-bodyexpansionpotentialenergysurface[J.Phys.Chem.A1155274(2011)].TheChebyshevrealwavepacketpropagationmethodisemployedtoobtainthedynamicalinformation,suchasreactionprobability,initialstate-specifiedintegralcrosssection,andthermalrateconstant.Itisfoundnotonlythatthereisareactionthresholdnear0.7eVinbothreactionprobabilitiesandintegralcrosssectioncurves,butalsothatboththeprobabilityandcrosssectionincreasefirstlyandthendecreaseasthecollisionenergyincreases.Theexistenceoftheresonancestructureinboththeprobabilityandcrosssectioncurvesisascribedtothedeeppotentialwell.Thecalculationoftherateconstantrevealsthatthereactionoccurringonthepotentialenergysurfaceoftheground-stateHS2isslowtotakeplace.

  • 标签: 反应概率 动力学计算 上海 量子 表面 截面曲线