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881.
Bian HD Gu W Xu JY Bian F Yan SP Liao DZ Jiang ZH Cheng P 《Inorganic chemistry》2003,42(14):4265-4267
The first mu(3)-oxalato-bridged copper(II) complex, [[Cu(3)(L)(3)(mu(3)-C(2)O(4))][Cu(L)(H(2)O)](ClO(4))(2)] x 0.5(H(2)O) x 0.5(CH(3)OH), where HL = N-ethyl-N'-salicylidene-1,2-diaminoethane, has been synthesized and characterized by variable-temperature magnetic susceptibility measurement. The complex exhibits ferromagnetic coupling between the oxalato-bridged copper atoms and antiferromagnetic coupling between the oxygen-bridged copper atoms. 相似文献
882.
Graphitic anode materials for lithium ion batteries processed under high humidity conditions show severe performance losses. The sensitivity of these materials towards humidity can be significantly reduced by adsorbing metal ions like silver or copper ions, with subsequent heat treatment of these composites. Results of X-ray photoelectron spectroscopy, high-resolution electron microscopy, thermogravimetry, and differential thermal analysis indicate that the deposited metals exist in metallic and carbide, MxC (M=Cu or Ag), forms. They remove or cover (i.e. deactivate) active hydrophilic sites at the surface of the graphite. These composites absorb less water during processing. The electrochemical performance, including reversible capacity, coulombic efficiency in the first cycle, and cycling behavior, is markedly improved. This approach provides a potentially powerful method to manufacture lithium ion batteries under less demanding conditions.Presented at the 3rd International Meeting on Advanced Batteries and Accumulators, 16–20 June 2002, Brno, Czech Republic 相似文献
883.
A novel chemiluminescence (CL) flow system for the determination of quinine is described. It is based on the direct chemiluminescence reaction of quinine and cobalt(III) in sulfuric acid medium. The unstable Co(III) was on-line electrogenerated by constant-current electrolysis. The chemiluminescence intensity was linear with a quinine concentration in the range of 0.1-100 mug ml(-1). The determination limit was 3.3x10(-8) g ml(-1). The whole process could be completed in 1 min. The proposed method is suitable for automatic and continuous analysis, and has been applied successfully to the analysis of quinine in pharmaceutical preparation. 相似文献
884.
Ming Xian LIU Li Hua GAN Gen CHEN Zi Jie XU Zhi Xian HAO Long Wu CHEN 《中国化学快报》2006,17(8):1085-1088
Recently the research on structures with an ordered two-dimensional(2D) pattern has attracted great attention due to its versatile applications in the fields of microelectronic and optoelectronic devices, displays, biochips and sensors, enzymatic immobilization, drug carriers, and photonic band gap materials. Various well-arrayed 2D structures have been made by the modern technique such as laser writing pattern fabrication, photoetching technique, micro-electromechanical systems based on scann… 相似文献
885.
A study of carboxylic-modified mesoporous silica in controlled delivery for drug famotidine 总被引:2,自引:0,他引:2
A series of pure silica MSU and carboxylic-modified MSU materials were prepared. The formation of mesoporous silica materials with terminal carboxylic groups on pore surface was performed by the acid-catalyzed hydrolysis of cyano to carboxylic. Then their potential applications in controlled drug delivery carriers were investigated. Drug famotidine was selected as a model molecule out of the consideration of the terminal amino groups in its molecule. The adsorption experiments show significant adsorption of famotidine on the carboxylic-modified MSU materials. And, the functionalization level of carboxylic groups has been found to be the key factor affecting the adsorption capacities of the modified MSU materials for famotidine. Subsequently, three kinds of release fluids, including simulated gastric medium, simulated intestinal medium, and simulated body fluid, were used to test the famotidine release rate from the carboxylic-modified MSU material. Obvious delayed effect has been observed for the famotidine release from the carboxylic-modified mesoporous silica material under the in vitro assays. 相似文献
886.
Cp2TiCl2及(MeCp)2TiCl2在Et3N或NaNH2存在下与苄醇类化合物反应,高产率地合成了6个未见文献报道的二茂钛(Ⅳ)苄氧基衍生物,甲基二茂钛(Ⅳ)苄氧基化合物,经元素分析,HNMR和IR光谱确定了化合物的结构,并对其部分性质进行了讨论。 相似文献
887.
本文提出了一个硫酸中间盐子循环用以代替分解水制氢的KNO_3-I_2混合循环中的电解反应,从而使原混合循环变为一个纯热化学循环。 相似文献
888.
Biosorption of copper(II) and zinc(II) from aqueous solution by Pseudomonas putida CZ1 总被引:1,自引:0,他引:1
Chen XC Wang YP Lin Q Shi JY Wu WX Chen YX 《Colloids and surfaces. B, Biointerfaces》2005,46(2):101-107
To study Pseudomonas putida CZ1, having high tolerance to copper and zinc on the removal of toxic metals from aqueous solutions, the biosorption of Cu(II) and Zn(II) by living and nonliving P. putida CZ1 were studied as functions of reaction time, initial pH of the solution and metal concentration. It was found that the optimum pH for Zn(II) removal by living and nonliving cells was 5.0, while it was 5.0 and 4.5, respectively, for Cu(II) removal. At the optimal conditions, metal ion biosorption was increased as the initial metal concentration increased. The adsorption data with respect to both metals provide an excellent fit to the Langmuir isotherm. The binding capacity of living cells is significantly higher than that of nonliving cells at tested conditions. It demonstrated that about 40-50% of the metals were actively taken up by P. putida CZ1, with the remainder being passively bound to the bacterium. Moreover, desorption efficiency of Cu(II) and Zn(II) by living cells was 72.5 and 45.6% under 0.1M HCl and it was 95.3 and 83.8% by nonliving cells, respectively. It may be due to Cu(II) and Zn(II) uptake by the living cells enhanced by intracellular accumulation. 相似文献
889.
Density functional theory has been applied at the B3LYP/6-311+G(d,p)//B3LYP/6-31G(d) level to examine the energetics of alpha,beta- versus beta,gamma-unsaturation for some common organic functional groups. Specifically, the relative stabilities of allyl-X (H2C=CHCH2X) and 1-propenyl-X (H3CCH=CHX) isomers have been computed for X = methyl, vinyl, phenyl, formyl, acetyl, methoxy, methylthio, methylsulfinyl, methylsulfonyl, sulfamoyl, and methoxysulfonyl, and the results are compared to available experimental data. The intrinsic preference of 3 kcal/mol for the 1-propenyl isomer when X = CH3 is exceeded by 2-4 kcal/mol for first-row conjugating groups, but it is not met for the sulfur-containing groups. In particular, alpha,beta-unsaturation is favored by less than 1 kcal/mol for the sulfone and sulfonamide analogues, while it is preferred by 8 kcal/mol for the vinyl-substituted case. Detailed structural results and torsional energy profiles are also reported. 相似文献
890.
Changzheng Wu Qing Yang Chao Huang Ping Yin Yi Xie 《Journal of solid state chemistry》2004,177(10):3522-3528
Pure hexagonal aluminum nitride (AlN) nanowhiskers have been successfully synthesized by directly reacting AlCl3 with NaN3 in non-solvent system at the low temperature of 450 °C for 24 h. The obtained products are characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy and selected area electron diffraction, which show that the obtained products are hexagonal phase AlN nanowhiskers with width from 10 to 80 nm and length up to several micrometers. The influencing factors of the formation of AlN nanowhiskers were discussed and a possible growth mechanism for AlN nanowhiskers was proposed. Additionally, the study on the corresponding optical properties and catalytic properties is also carried out. 相似文献