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991.
Introduction Jujuba is the fruit of Zizyphus genus(Rhamnaceae) which has been used as a crude drug. Now quite a lot of botanists, chemists and pharmacologists at home and abroad have been deeply interested in the studies on it. Besides the studies on its fruit, a great deal of research work on its other parts has been done So far more 相似文献
992.
Five oxovanadium(Ⅳ) dinuclear complexes described by the overall formula [(VO)2(IA)L2]-SO4, where IA represents the dianion of iodanilic acid and L denotes 2,2'-bipyridine (bpy) ; 4,4'-dimethyl-2,2'-bipyridine (Me2-bpy); 1,10-phenanthroline (phen); 4,7-diphenyl-1, 10-phenanthroline (Ph2-phen) and 5-nitro-l, 10-phenanthroline (NO2-phen) , have been synthesized and characterized by elemental analyses, molar conductivity and room-temperature magnetic moment measurements, IR and electronic spectral studies. It is proposed that these complexes have IA-bridged structures and consist of two oxovanadium(Ⅳ) ions each in a square- pyramidal environment. The complexes [ ( VO)2 (IA) (bpy )2 ] SO4 (1) and [ ( VO )2 ( IA) ( phen)2 ] -SO4 (2) were further characterized by variable temperature (4.2-300 K) magnetic susceptibility measurements and the observed data were fitted to the modified Bleaney-Bowers equation by the least-squares method, giving the exchange integral J = -2.15 cm-1 for 1 and J = - 9.88 cm-1 for 2 相似文献
993.
Seven new μ-isophthalato dinuclear lanthanide(Ⅲ) complexes, namely [Ln2(IPHTA)(Me2-phen)4-(ClO4)2](ClO4)2 (Ln = La, Nd, Sm, Eu, Gd, Ho, Er), where Me2-phen denotes 2,9-dimethyl-1, 10-phenanthroline (Me2-phen) , IPHTA represents isophthalate dianion, have been synthesized and characterized by elemental analyses, molar conductance measurements, IR, ESR and electronic spectra. The variable-temperature magnetic susceptibilities of [Gd2( IPHTA) (Mez-phen)4 (ClO4)2] (ClO4)2 complex were measured in the temperature range of 4-300 K and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, H = - 2JS1 · S2, giving the exchange parameter J =- 0.19 cm-1 . This result is commensurate with a weak antiferromagnetic spin-exchange interaction between Gd(Ⅲ)-Gd(Ⅲ) ions within the complex. 相似文献
994.
Five oxovanadium(IV) dinuclear complexes described by the overall formula [(VO)2(IA)L2SO4, where IA repents the dianion of iodanilic acid and L denotes 2, 2′-bipyridine (bpy); 4,4′-dimethy12,2′-bipyridine (Meo-bpy); 1,10-phenanthroline (phen); 4,7-diphenyl-l, 10-phenanthroline (Ph2-phen) and 5-nitro-1, 10-phenanthroline (NO2-phen), have been synthesized and characterized by elemental analyses, molar conductivity and roomtemperature magnetic moment measurements, IR and electronic spectral studies. It is proposed that these complexes have IA-bridged structures and consist of two oxovanadium(IV) ions each in a square pyramidal environment. The complexes (VO)2(IA) (bpy)2]SO4, (1) and[(VO)2( IA) (phen)2 ]SO4 (2) were further characterized by variable temperature (4.2–300 K) magnetic susceptibility measurements and the observed data were fitted to the modified Bleaney-Bowers equation by the least-squares method, giving the exchange integral J = - 2.15 m?1 for 1 and J = - 9.88 cm?1 for 2. This result indicates that there is a weak antiferromagnetic spin-exchange interaction between the two VO2+ ions within each molecule. 相似文献
995.
本文报道了一种合成Germatrane及类似物Germatrantrione配合物的新方法. 有机锗倍半硫化物与三乙醇胺反应得Germatrane; 与氨三乙酸反应得Germatrantrione. 本文利用此法合成4个Germatrane类化合物(1), 5个Germatrantrione.DMF配合物(2), 2个Germatrantrione.DMSO配合物(3). 所有化合物经元素分析, IR, ^1H NMR, MS和差热-热失重分析 证实了它们的组成和结构. 相似文献
996.
997.
基于Fe2+-H2O2-四甲基联苯胺(tetramethylbenzidine,TMB)显色体系测定过氧化氢酶(CAT)活性。在Fe 2+催化作用下过氧化氢与四甲基联苯胺发生显色反应。加入CAT后,A值减小,显然CAT对显色反应具有阻抑作用。在优化实验条件下,CAT活性在0.00~0.10 U·mL-1之间与△A呈现良好的线性关系:△A=0.0348+19.19 E(U·mL-1)(r=0.9977),检出限为0.0016 U·mL-1。采用酶失活样品液作空白,可有效排除样品共存还原性物质的干扰;方法用于健康人体血清CAT活性检测,为广大临床检验工作者提供参考。 相似文献
998.
LI Xiao-ling ZHAO Bing WU Yu-qing XU Wei-qing LI Guo-wen WU Ying BAI Fang CUI Shu-wen 《高等学校化学研究》1998,14(4):395-398
IntroductionInrecentyears,Langmuir-Blodget(LB)filmshaveatractedmuchatentionbecauseoftheirposibilitiesasfunctionalmoleculardev... 相似文献
999.
聚血红素修饰电极对儿茶酚类化合物和抗坏血酸氧化的电催化作用研究 总被引:3,自引:0,他引:3
电催化是化学修饰电极研究的中心课题之一,血红素是一种重要的铁卟啉化合物,其中的铁原子能够以两种价态存在.我们采用循环伏安法将血红素修饰于电极表面,得到了氧化还原体(redox)型化学修饰电极,并用于儿茶酚类化合物和抗坏血酸的电催化氧化研究.采用伏安法... 相似文献
1000.
Spectroscopic characterizations of carbazole-TCAQ salt were investigated by means of UV-visible and fluorescence spectra. The results show that carbazole and TCAQ can form a kind of charge-transfer salt whose characteristic adsorption is π→π* of 248 nm when the mixture of the two compounds is irradiated by UV-light, and the charge-transfer salt becomes more stable with the increase of irradiation time. 相似文献