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591.
Jian Chao YUAN Yu Hua ZHANG Shi Jie LU* State Key Laboratory for Oxo Synthesis Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 《中国化学快报》2001,(6)
Alternating copolymerization of (-olefins with carbon monoxide (CO) catalyzed by cationic palladium-chiral ligand complexes is of great interest due to the potential use of the resulting polymer as a new material1. Recently, enantioselective alternating copolymerization of CO with styrene has been reported by us using PdCl_2-CuCl2-chiral phosphine catalyst2. Here, we first report enantioselective alternating copolymerization of CO with propylene (P) using [(DDPPI)Pd(CH3CN)4](BF4)2 as … 相似文献
592.
Hong Yun GUO Yun Fa ZHENG Yong Min ZHANG * Department of Chemistry Zhejiang University at Xixi Campus Hangzhou Department of Chemistry Zhejiang Normal University Jinhua Department of Chemistry Lishui Teachers College Zhejiang 《中国化学快报》2001,(5)
Selenium is an essential element in living organism. It is reported that the selenosulfides have been transported in vivo in glutathione or coenzyme-A1. It is also discovered in low concentration in garlic2. In organic synthesis, selenosulfides are useful intermediates3. Several methods for the formation of sulfur-selenium bond have been reported. For example, the compounds including S-Se bond were prepared by chloroamination of thiols and selenols4; by heating the selenocyanate with thiols5… 相似文献
593.
A compound {[Co(azpy)_2(NCS)_2]·1/4EtOH·1/2H_2O}_n(1), where azpy=4,4'-azobispyridine, was synthesized and characterized by means of IR, TGA-DTA, magnetic susceptibility and X-ray single crystal diffraction. It consists of two independent sets of fully interlocked two-dimensional networks with the dihedral angle 61.7°, organized in parallel stacks of the sheets which are made of edge-shared [Co(Ⅱ)]_4 squares separated by 0. 9062nm, and defined size rhombic channels. The thermal gravimetric analysis indicates that the framework is stable up to 198℃. The variable-temperature magnetic susceptibility measurements indicated that there is a weak antiferromagnetic interaction between the cobalt(Ⅰ) ions in the complex (1). 相似文献
594.
WU Shi-hua* * WEI Wei ZHU Chang-ying HUANG Wei-pingZHANG Shou-min ZHENG Xiu-cheng ZHANG Shu-hong ZHAO Wei-jun 《高等学校化学研究》2001,17(4):439-444
Co-Pd bimetallic catalysts immobilized with four kinds of resins with different specific areas were prepared by means of the solvated metal atom impregnation (SMAI) method. The results of the XRD and the magnetic measurement showed that as the specific area of the resin increased, the particle sizes of Co and Pd on the catalysts with the same metal content decreased, so the catalytic activity of the catalysts for the hydrogenation of diacetone alcohol as well as the reduction of oxygen on the fuel cell electrode increased. Below 140 , the conversion of diacetone alcohol increased as the reaction temperature increased, and above 140 , the conversion decreased because of the rupture of the resin. 相似文献
595.
针对以往基于质点速度波形测量使用拉格朗日分析法反推材料动态力学性能时,需作某种简化假定或者必须同时实测应力边界,而在实验过程中的边界应力数据在某些情况下测不到或测不准的状况.因此基于路径线法和零初始条件,提出了一种改进的拉格朗日分析法,新方法可不涉及边界应力,直接反推出材料高应变率下的动态应力应变曲线.并且运用该方法对有机玻璃材料的动态性能进行了数值模拟研究分析,其结果与运用特征线法求得到的数据非常吻合,从而证实了该方法的可靠性和有效性. 相似文献
596.
利用UG自带的STEP运动仿真函数可控制模型驱动的运动时间段,从而获得从动件在不同时间段运动变化规律的特点,分析了UG仿真模块中的运动控制函数,提出一种将运动函数模型转化为UG仿真模块内的STEP运动控制函数,以方便设计者更好地掌握机构的运动仿真变化规律.还阐述了在UG仿真模块中,如何使用STEP运动函数来控制曲柄摇杆机构运动时间以及对双摇杆机构在运动极限范围内的运动仿真. 相似文献
597.
1 INTRODUCTIONThe coordination chemistry oftransition metalcomplexeshasbecomeofremark able interestin recentyears.Sotoftetal.reported the structure of Ni( CH3CN) 6·Zn Cl4 〔1〕.Recently,Shyu etal.reported the structure of〔 Ni( bipy) 3〕〔 Fe( CN) 5 ( NO)〕· 3 H2 O〔2〕.Herein we reportthe structure oftitle complex〔 Ni( bipy) 3〕〔 Zn Cl4 〕 which issimilarto theformertwo complexes.Itisvery interesting to synthesizebimetallic compoundsfor both theoreticalstudy and practicalapp… 相似文献
598.
采用溶剂热法合成了超小尺寸三氟化镧(LaF3)纳米晶. 利用XRD、TEM等对其进行结构与形貌表征,结果显示制得的纳米颗粒为LaF3纳米晶,且具有高度均一的尺寸分布和良好的结晶度,颗粒尺寸为6±0.4 nm. 通过共掺杂镱铒两种稀土元素,所得材料在近红外光激发下(980 nm)可发射出明亮的绿光;发光光谱显示,在524,544,655 nm等位置有较强的发射峰. 利用聚琥珀酰亚胺高分子(PSI)对油溶性的纳米颗粒表面进行功能化修饰,将其成功转移水相. 利用叶酸对其进行进一步生物标记,可与肝癌细胞表面叶酸受体特异性识别,成功地实现了肝癌细胞上转换绿色发光成像研究. 相似文献
599.
Synthesis and Crystal Structure of N′-(4-fluorobenzylidene)-2-(1H-1,2,4-triazole-1-yl)acetohydrazide
LI Wei-hua ZHANG Shu-fang + HOU Bao-rong YU Zhi-gang *. Institute of Oceanology Chinese Academy of Sciences Qingdao P. R. China. College of Chemistry Chemical Engineering Ocean University of China Qingdao P. R. China 《高等学校化学研究》2006,(5)
IntroductionBoth triazole derivatives and Schiff base have beenreported to possess significant antifungal[1—3]and plantgrowth regulatory activities[4—6].Triazole drugs are alsovery common in the medical field,which has given animmense impetus to the res… 相似文献
600.