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Catalytic wet air oxidation of butyric acid solutions using carbon-supported iridium catalysts 总被引:1,自引:0,他引:1
Aqueous solutions of butyric acid were treated by catalytic wet air oxidation using carbon-supported iridium catalysts in a stirred reactor. Under the operating conditions of 6.9 bar of oxygen partial pressure and 200 °C of temperature, conversions up to 52.9% after 2 h were obtained depending on the type of catalyst used. The effects of butyric acid initial concentration, loading of catalyst, oxygen partial pressure and temperature were investigated and the empirical rate law for acid conversion is presented. Oxidation intermediates such as propionic and acetic acid were identified. The heterogeneous catalyzed free-radical oxidation of butyric acid is discussed. 相似文献
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“Symmetric materials” devices, where both electrodes are made of the same electrochromic materials, allow the in situ study of side reactions. Each transferred charge that is not used for the expected electrochromic reaction will cause a colour change in the whole symmetric device. Two electrochromic materials, WO3 and IrO2, are successively used to show how to obtain information about side reactions such as faradaic efficiency, reversibility and potential limits from the symmetric experiment. This in situ approach with a polymer electrolyte shows significant differences compared to results obtained with studies in aqueous electrolytes. 相似文献
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Dr. Xicheng Liu Mingxiao Shao Congcong Liang Jinghang Guo Guangxuan Wang Xiang-Ai Yuan Zhihong Jing Laijin Tian Prof. Dr. Zhe Liu 《Chembiochem : a European journal of chemical biology》2021,22(3):557-564
A series of half-sandwich structural iridium(III) phenanthroline (Phen) complexes with halide ions (Cl−, Br−, I−) and pyridine leaving groups ([(η5-CpX)Ir(Phen)Z](PF6)n, Cpx: electron-rich cyclopentadienyl group, Z: leaving group) have been prepared. Target complexes, especially the Cpxbiph (biphenyl-substituted cyclopentadienyl)-based one, showed favourable anticancer activity against human lung cancer (A549) cells; the best one ( Ir8 ) was almost five times that of cisplatin under the same conditions. Compared with complexes involving halide ion leaving groups, the pyridine-based one did not display hydrolysis but effectively caused lysosomal damage, leading to accumulation in the cytosol, inducing an increase in the level of intracellular reactive oxygen species and apoptosis; this indicated an anticancer mechanism of oxidation. Additionally, these complexes could bind to serum albumin through a static quenching mechanism. The data highlight the potential value of half-sandwich iridium(III) phenanthroline complexes as anticancer drugs. 相似文献
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Diana R. Melis Chiao-Yu Hsiao Dr. Jill M. Combrinck Prof. Lubbe Wiesner Prof. Gregory S. Smith 《Chembiochem : a European journal of chemical biology》2021,22(9):1568-1572
A fluorescent analogue of a previously synthesised N,N-chelated IrIII complex was prepared by coordination of the organic ligand to an extrinsic bis(2-phenylpyridine)iridium(III) fluorophore. This cyclometallated IrIII complex in itself displays good, micromolar activity against the chloroquine-sensitive NF54 strain of Plasmodium falciparum. Live-cell confocal microscopy found negligible localisation of the fluorescent complex within the digestive vacuole of the parasite. This eliminated the haem detoxification pathway as a potential mechanism of action. Similarly, no localisation of the complex within the parasitic nucleus was found, thus suggesting that this complex probably does not interfere with the DNA replication process. A substantial saturation of fluorescence from the complex was found near phospholipid structures such as the plasma and nuclear membranes but not in neutral lipid bodies. This indicates that an association with these membranes, or organelles such as the endoplasmic reticulum or branched mitochondrion, could be essential to the efficacies of these types of antimalarial compounds. 相似文献
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James R. Strife John G. Smeggil Wayne L. Worrell 《Journal of the American Ceramic Society》1990,73(4):838-845
The reactions of titanium carbide and hafnium carbide with iridium have been studied in thin film couples fabricated by vapor deposition processes. The reaction product layers after exposure in the temperature range of 1923 to 2400 K are dependent on the stoichiometry of the metal carbide layers and range from simple solid solutions to MIrx compounds. The observed microstructures are predictable from available thermochemical data. The morphology of residual carbon in the reacted metal carbide-iridium product layer varies from interfacial deposits to uniform carbon dispersion and depends upon exposure temperature and metal carbide stoichiometry. 相似文献
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碘和硫增感剂在卤化银颗粒表面的分布*李金培**王素娥(中国科学院感光化学研究所,北京100101)关键词碘化银,硫增感,软硬酸碱原理碘在卤化银微晶中的含量和分布对感光度的影响引起乳剂配方设计者的广泛注意和重视.颗粒中的碘引起其内部结构和表面结构的改变... 相似文献