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91.
Proteins containing dinuclear Cu (II), Zn (II) centers play paramount roles in biology1. As mimetic of metal-dependent esterase, dinuclear Cu (II) and Zn (II) complexes have received a great deal of attentions2~6. They are of interest in the field of biomimetic chemistry to provide an improved understanding of the function of the biological sites and as potential catalysts for substrate oxidations. Schiff base type polydentate ligands which contain centeral hydroxyl group have been wid…  相似文献   
92.
New type of spherical pore Al alloy foam with low porosity and high strength   总被引:15,自引:0,他引:15  
The Ultra Light Metal Structure with variouskinds of pores (open, close) realizes the lightness andmultifunction of structural material. The functionsinclude lightness (ρ < 1), high specific strength, highenergy absorption, sound insulation, heat insulationand electromagnetism shield. It is one of the hotspotsin material research nowadays[1— . The requirements 6]of high speed movement and high technology make Alalloy foam, which has higher specific st…  相似文献   
93.
在C60单晶(111)解理面上制备出厚度约30 nm的K3C60单晶膜.利用同步辐射光源,在低温下(约150K)测量了样品法向发射的角分辨光电子谱.观察到K3C60导带和价带明显的色散.导带的光电子谱峰可清晰分辨出4个子峰,这些子峰的最大色散超过0.5eV,并且色散曲线与K3C60的一维无序晶体结构模型下的能带理论基本吻合,只是子带间隔差异较大.  相似文献   
94.
K3[VO(O2)2(C2O4)]2H2O, (abbr. BpV (ox)) pertains to peroxovanadium (abbr. pV) complexes, which have been attracted considerable attention nowadays, since they are inhibitors of tyrosine phosphatase and may be developed into a new kind of drugs for the treatment of diabetes1. According to the evidence on water-biperoxovanadium, the molecular mechanism of insulin-like effects of pV involves in irreversibly oxidizing the catalytic cysteine at the active site of the target enzyme2,3. However…  相似文献   
95.
Recently, the studies on the interaction of DNA with small molecules have been attracting much interest1-6. These researches not only gave the important information about thermodynamics and kinetics, but also can prompt the combination between the electrode substances and biomacromolecule with super catalysis and sensor character. It is of great significance in understanding energy conversion and metabolism in live body, biomolecular structure, various physical and chemical characters for e…  相似文献   
96.
Among various conducting polymers, polyaniline (PANI) is a unique and promising candidate for practical applications because it is not only highly stable in air and in some solvents, but also exhibits dramatic changes in its electronic structure and physical properties in protoactivate state1,2,3. The carbon nanotubes (CNTs) have been proven to possess exotic properties, such as high mechanical strength, flexibility and electric conductivity. The study of carbon-based nanostructures and ma…  相似文献   
97.
Since Daly reported the structure of epibatidine and its potent analgesic activity in 19921, study on the synthesis of epibatidine and its derivatives and relationships between the structure and activity of epibatidine has received much attention2. During the course of our research for the synthesis of epibatidine derivatives, N-boc-2, 5-bis(trimethylsilyl)pyrrolidine 4 was used as the key intermediate to construct the skeleton of epibatidine via the 1, 3-dipolar cycloaddition (Scheme 1). Ac…  相似文献   
98.
The various distillation of petroleum contains arenes. For environmental protection, the hydrogenation of arenes becomes important. The amorphous alloy is a new class of material with special catalytic properties for reduction arenes1-4. In this paper, we prepared the Ni-B/TiO2 and Ni-B/Al2O3 amorphous catalysts by impregnation and reduction by KBH4 solution. Their catalytic activities for hydrogenation arenes were tested by the hydrogenation of 1,3,5-trimethylbenzene (TMB) in the co…  相似文献   
99.
The drug overdose and addiction is a serious international problem. Therefore developing a rapid, accurate, convenient and cheap method for detecting morphine in urea is useful and necessary, especially for investigation of epidemiology, identification of medical jurisprudence and determination of drug addict etc. There are many compounds that are similar to morphine in chemical structure and tend to have cross-reaction with the anti-morphine antibody. In order to reduce the cross reaction a…  相似文献   
100.
Calixpyrroles, as new macrocyclic receptors, have gain increasing interest in host-guest chemistry. Pioneering work in this area by Sessler and co-workers have evidenced that calix[4]pyrroles are effective anion binding agents and have used for anion binding, sensing and new anion separation technologies1, 2. In this letter, we report that calix[4]pyrroles A, B and C3,4 (Scheme 1) can serve as additives in CZE for the separa- tion of halide ions. Scheme 1 A B C When analyzing anions with…  相似文献   
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