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991.
Separation of Six Pyridoncarboylxic Acid Derivatives by Micellar and Microemulsion Electrokinetic Chromatography 总被引:1,自引:0,他引:1
Jian De LU Wei YUAN Xiao Yun FU* Analytical Testing Center Yuquan Campus Zhejiang University Hangzhou 《中国化学快报》2001,(2)
Micellar electrokinetic chromatography (MEKC) and microemulsion electrokinetic chromatography (MEEKC) are two kinds of electrokinetic capillary chromatography (EKC), which are characterized of high solubilization capacity and separation efficiency. In our previous work, some polar organic compounds and hydrophobic neutral compounds were separated successfully by EKC1-3. In this paper, these methods were used for separating six pyridoncarboylxic acid derivatives with similar structures. T… 相似文献
992.
Shu WANG Yu Liang LI* Chi Min DU Zhi Qiang SHI Sheng Xiong XIAO Hong Juan FANG Dao Ben ZHU Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing 《中国化学快报》2001,(12)
Introduction During the past decade, nanometer-sized metal clusters, special the gold clusters, possessing unusual physical and chemical properties have been extensively investigated1-5. In recent years, a new effort has been focused on fabricating ordered metal nanoparticles with well-defined two or three dimensions using nanometer-sized metal clusters as building blocks6-9. This will provide a new horizon to develop novel optical and nanoelectronic devices. Ordered nanoparticle assemblie… 相似文献
993.
Wei CAO Wei LIAN Yu Bai BAI Chun Yan LIU Hui Bo SHAO* Center for Intelligent Materials United Research 《中国化学快报》2001,(3)
Metal complexes, which are composed of metal ions and amphiphile ligands, show some structural peculiarities in Langmuir-Blodgett (LB) films. In the past studies, the metal complexes were mainly composed of the transitional metal ions1,2. The metal ions in IA, IIA and IIIA were seldom mentioned. Further more, the aluminium element is at the position where the typical metal elements transit to the typical non-metal elements in the periodic table of elements and study on the properties of … 相似文献
994.
Yun Yan GAO Yong Yong LIU Bo Jie WANG Bao Wen ZHANG* Yi LI* Technical Institute of Physics Chemistry 《中国化学快报》2001,(4)
IntroductionThe photochemistry of provitamin D3 (Pro) has been studied extensively in many years1-4. As shown in Scheme 11, irradiation of provitamin D3 in organic solvents results in its photoisomerization to previtamin D3 (Pre). Previtamin D3 can be thermally transferred into vitamin D3 (VD3), which is of commercial interests. However, previtamin D3 also undergoes the photochemical back reaction leading to the regeneration of provitamin D3 and the photoisomerization resulting in the und… 相似文献
995.
LI Hong ZHANG Wenfan HE Binglin The State Key Laboratory of Functional Polymeric Materials for Adsorption Separation. Institute of Polymer Chemistry Nankai University Tianjin P. R. China 《Chinese Journal of Reactive Polymers》2001,(2)
Comb graft copolymers (CGC), a special kind of the hyper-branched polymer series, have unique and excellent properties [1,2]. Synthesizing CGC via ring opening metathesis polymerization (ROMP) of cycloolefinyl macromonomer catalyzed (initiated) by the molybdenum carbene complex (Schrock complex) is a newly-developed method [3,4]. Though showing excellent catalytic behavior the complex has the disadvantage of highly moisture and oxygen sensitive and is hence operation-inconvenient. We repor… 相似文献
996.
Non-barrier mudflats in the Changjiang Estuary is examined to obtain preservation potentials and deposition rates over different time scales. The preservation potential of couplet is ca. 46.6% within daily scale and decreases as the time-interval extending, with 9.2% on a semi-lunar scale and 3.7% on a seasonal scale. In the long term, only 1.6% of daily deposition can potentially be preserved in the tidal flat sequence and other 98.4% have been eroded and leave sedimentary discordances, discernable or un-discernable, in the mudflat deposits. A negative log-linear relationship is examined between sedimentation rates and the time spans. The length of sedimentary hiatuses on the mudflat deposition were estimated with considerable uncertainty, but it can provide from an actualistic base some further insights into the nature and origin of ancient mudflat deposits with emphasis on the sedimentary discordances. 相似文献
997.
分离流动激振控制的实验研究 总被引:1,自引:0,他引:1
综述了二维后向台阶、翼型以及轴墩称钝体等典型分离流动激振控制的实验研究.分析了激振控制分离流动的作用机理,得到了一个具有普适性的最佳激振频率范围.另外,介绍了目前常用的激振手段,并对其发展方向进行了展望 相似文献
998.
利用含时多量子非线性Jaynes-Cummings模型时办禁子Paul阱中在驻波场作用下单个离了的动力学行为作了一个完备的描述,工研究了它的含时因素及非线性特性对其动力学行为的影响,它于精确测量和控制Paul阱的单个离子的运动具有重要的意义。 相似文献
999.
分别求解囚禁了一个和两具共面超冷离子的Penning阱系统的薛定谔方程。 相似文献
1000.
利用Guassian94程序和QCISD/6-311++G方法得到He-HF和He-FH两种线性平衡结构,计算出了这两种弱结合分子的结构参数、离解能和二阶力常数。在此基础上,利用多体项展式方法民出He-HF(X^1Σ^+)体系的分析势能函数,得到的势能面准确地再现了He-HF和He-FH两种线性结构。 相似文献