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81.
波长19.6nm的类氖锗X光激光适合作为诊断激光等离子体界面不稳定性的光源。用经过实验检验的系列程序对预-主短脉冲驱动类氖锗进行了系统的优化设计和理论分析。采用2%~3%的预脉冲强度,6~8ns的预-主脉冲时间间隔,在4×1013W/cm2功率密度驱动下, 波长19.6nm增益区的宽度可以超过60μm,增益区的维持时间可以达到90ps。对于16mm长的平板靶,增益系数可达11.8/cm;弯曲靶增益系数可达13.3/cm;单靶小增益长度积可达21.3,单靶就可以获得饱和增益。采用双靶对接,其小讯号增益可达38.4,可以获得深度饱和增益,能满足应用演示所需的X光激光光源。 相似文献
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YAN Xiaomin ZHAO Lin SHAO Jianhui TAN Xin SONG Zhengxiao School of Chemical Engineering Technology Tianjin University Tianjin China Slichem Liquid Material Co. Ltd. Shijiazhuang China 《Chinese Journal of Reactive Polymers》2004,(Z1)
1. INTRODUCTION Methionine, namely 2-amido-4-thiomethyl butyric acid with a structure of CH3SCH2CH2CHCOOH, is one of the essential amino acids and has two natural enantionmers, D and L-methionine. The mixture of L- and D-isomers can be used as analeptics or nutritive additives to maintain the equilibrium of amino acids of feed [1,2]. L-methionine can release active methyl and accelerate the synthesis of choline, which further speeds up the conversion of the lipid accumulated in liv… 相似文献
84.
LI Shufeng LI Qian YANG Xinlin HUANG Wenqiang** State Key Laboratory of Functional Polymer Materials for Adsorption Separation Institute of Polymer Chemistry Nankai University Tianjin China 《Chinese Journal of Reactive Polymers》2004,(Z1)
1. INTRODUCTION The development of efficient polymer-supported catalysts has attracted much attention [1]. For obtaining polymeric catalysts, catalytically active groups were introduced onto polymers mostly by copolymerization of the appropriate monomers bearing the desired catalyticfunctionalities (e.g. imidazole, OH, and COOH) or by modification of preformed polymers.Another possibility involves the attachment of side chains, containing the desired arrangement of functional groups, o… 相似文献
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CUI Xiao-bing ZHENG Shou-tian SUN Yan-qiong YANG Guo-yu ** . Coordination Hydrothermal Chemistry Group State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou P. R. China . State Key Laboratory of Coordination Chemistry Najing University Nanjing P. R. China 《高等学校化学研究》2004,(1)
IntroductionPolyoxometalatesarewidelystudiedfortheirin terestingapplicationsincatalysis ,electronicconduc tivity ,magnetism ,nonlinearopticsandmedicine[1— 4 ] .Whilethemechanismofthesynthesisofpolyoxometalatesremainselusiveandisoftende scribedasself assembly ,thereseemstobeanincreas inguseofthecombinationofthehydrothermalmethodandthestructure directingtemplate .There searchwiththismethodhasdemonstratedthatanum beroftransitionmetaloxides ,typicallyreducedmolybdenumoxides ,mixedvalancevanadiumo… 相似文献
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5,6-Dihydro-OSW-1 (1) was synthesized following our previous procedure for the total synthesis of OSW-1. This compound demonstrated slightly stronger potency than that of OSW-1 against the growth of cancer cells. 相似文献
89.
Introduction In the previous studies on the oxidation reaction,peroxydisulfate was widely used as an oxidizingagent.1-5 One of the advantages of this oxidant lies in itsstability in a wide range of pH values. The reaction be-tween Fe(CN)5L3- (L=N-aromatic heterocyclic li-gands) and S2O8 2- has been proved to proceed throughan outer-sphere electron transfer mechanism.5 For a re-action [(Eq. (1)] to be under an outer-sphere mechanismthe steps involved are the formation of a reactant … 相似文献
90.
The polyacrylic acid functionalized polystyrene nanospheres were synthesized and self-assembled into irregular, densely packed monolayers in non-aqueous media. The polymer nanoparticles were chemically adhered to substrates. The morphologies of the resulting films were investigated. The impact of the volume fraction of alcohol in the mixed solvents on the particle adsorption and fabrication of nanosphere assembled films was examined. 相似文献