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101.
Schalley CA Lützen A Albrecht M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(5):1072-1080
Functional molecules require a high degree of complexity which is difficult to achieve by covalent synthesis. This article discusses supramolecular approaches to the creation of larger architectures through noncovalent bonds, self-assembly, and template strategies. It highlights selected examples for the structural and conformational control of function and attempts to identify difficulties and challenges which may arise in future. 相似文献
102.
S. Yu. Ryabova E. Yu. Khmel’nitskaya N. A. Rastorgueva N. B. Grigor’ev V. G. Granik 《Russian Chemical Bulletin》2004,53(12):2830-2833
Electrochemical reduction of 1-aryl-2-oxo-1,2,3,6-tetrahydro[1,4]diazepino[6,5-b]indole 4-oxides, 2-oxo-1-phenyl-1,2,3,6-tetrahydro[1,4]diazepino[6,5-b]indole, and 2-oxo-1-phenyl-1,2,3,4,5,6-hexahydro[1,4]diazepino[6,5-b]indole was studied. The results obtained were compared with previous data for the reduction of 4-oxides with formamidinesulfinic acid.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2715–2718, December, 2004. 相似文献
103.
在电极袭面反应物浓度均匀的近似假设下,得到了微圆盘电极上暂态可逆反应的一般解.然后利用该一般解得到了微圆盘电极上耦合一级均相反应的可逆电极反应CE、EC、EC′和ECE 的稳态电流计算公式. 相似文献
104.
以Mn2O3和氢氧化锂为原料,通过焙烧合成出o-LiMnO2。用X射线衍射和扫描电镜对不同温度下合成的粉末样品进行了表征,并研究了材料的电化学性能。通过对不同温度条件下烧结样品的晶胞参数、布拉格(110)晶面峰半高宽及电化学性能研究发现:600 ℃下合成样品的半高宽最大,堆垛层错率高,同时电化学性能也最好,首次放电容量达到156 mAh·g-1,20次循环后仍保持在140 mAh·g-1以上。中高温固相合成的o-LiMnO2材料,在晶粒范围大小相近时,材料电化学性能与材料堆垛层错率相关。 相似文献
105.
106.
107.
环氧环己烷的电化学合成 总被引:6,自引:0,他引:6
环氧环己烷的电化学合成何俊翔*周锦成(温州师范学院化学系温州325003)关键词电化学环氧化,环氧环己烷,环己烯,钛基氧化物电极1996-11-22收稿,1997-06-05修回间接电解氧化合成环氧化合物的研究已有报道[1~4].它们均在铂电极上完成... 相似文献
108.
A simple and automated methodology for a sensitive electrochemical detection of enzyme immunoassays that employ alkaline phosphatase (AP) as label has been developed. A flow injection system with programmable pump, valve and cell functions, amperometric detection of indigo and screen-printed electrodes (SPEs) are responsible for the advantages of this methodology. Amperometric detection at a low potential of indigo, the product of the enzymatic hydrolysis of the substrate 3-indoxyl phosphate (IP), is combined with a flow injection system. This incorporates in the flow cell a disposable screen-printed board provided with a graphite working electrode. No electrode pretreatment is necessary to obtain reproducible signals. The system was applied to the determination by an enzyme-linked immunosorbent assays (ELISA) of pneumolysin (PLY), a toxin related to respiratory infections. Linear calibration curves for low and high concentration ranges were obtained. These were also performed in a proteic matrix and linearity was also obtained. 相似文献
109.
XIE Qing-Ji PANG Xiao-Yong NIE Li-Hua YAO Shou-Zhuo Department of Chemistry Chemical Engineering Hunan University Changsha Hunan China 《中国化学》1994,12(5):425-431
Piezoelectric transmission spectroelectrochemistry (PTSEC), i.e., the combination of electrochemistry and spectroelectrochemistry (SEC) with electrochemical quartz crystal microbalance (EQCM) technique is reported by using a normal piezoelectric quartz crystal (PQC) as an optically-transparent electrode (OTE). A theoretical relationship between the PQC response and the spectroelectrochemical response is derived and used to estimate the apparent molar absorptivity of the absorbing species deposited on the OTE on the PQC surface. The complex of copper with aspartic acid is used to test this new PQC-SEC technique. Results show that the combination of three such diverse techniques provides a very useful methodology for studying electrode processes and electrode surface characteristics in situ. 相似文献
110.
Qiong Yu Lai Ji Zheng LuXiao Bo Su Xiao Yang Ji 《Journal of solid state chemistry》2002,165(2):312-316
Spinel compound LiNi1−xMnxVO4 (0≤x≤0.4) had been prepared by using the moist chemical method. X-ray diffraction spectra showed that the lattice constant increased with x in the LiNi1−xMnxVO4, XPS spectra indicating that Li1s had a chemical shift towards lesser binding energy, and manganese in LiNi1−xMnxVO4 existing as the mixed valence of Mn2+ and Mn3+. The electrochemical charge and discharge testing at a current density of 0.1 mA/cm2 between the potentials of 4.0 and 3.0 V vs Li/Li+ in 1 mol/dm3 LiPF6/EC+DEC (1:1 by volume) at 25°C showed that LiNi1−xMnxVO4 cell has a better rechargeability, but a lower cell voltage of 4.0 V vs Li/Li+ than that without the doping sample, and the capacity and the cycle efficiency of the Li/LiNi1−xMnxVO4 cells increased with x in the LiNi1−xMnxVO4. 相似文献