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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
3.
“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
4.
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
5.
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
6.
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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碘离子掺入到高氯乳剂可以显著提高其感光性能。碘离子掺入到亚表层可增加乳剂的光吸收,提高感光度,增加反差。最佳掺入量为0.6%mol/mol Ag,掺入位置在65%Ag处,KI加入速度约8s。在一定范围内(小于1.5%mol/mol Ag)碘离子掺入亚表层对清晰度没有明显影响。如果铱掺杂的掺杂位置为亚表层,掺杂量为10~(-7)mol/mol Ag,铱络合物可有效地改善含碘高氯乳剂的高照度互易律失效。 相似文献
9.
The oxidation products formed at 500 and 700°C on an amorphous Ta-44.5 at% Ir alloy in an Ar-0.1% O2 gas mixture were characterized using SEM, XRD, EPMA, TEM, STEM, AES, and XPS. Initially, a thin (3–4 nm) layer of Ta2O5 formed at the surface of the alloy. Continued growth of the Ta2O5, which occurred very rapidly, involved diffusion of oxygen anions from the Ta2O5/gas interface to the alloy/Ta2O5 interface, where tantalum was selectively oxidized. Because the oxide grew more quickly than iridium could diffuse back into the alloy, the iridium coalesced into platelets of crystalline iridium-rich alloy that were oriented approximately parallel to the oxide/alloy interface, and which became embedded in a matrix of Ta2O5. The unoxidized core remained in the glassy state. The oxidation process and/or the dissolution of oxygen into the unoxidized alloy caused the alloy to become embrittled. 相似文献
10.
根据阳极在各行业中应用的要求,从贵金属(铂、铑、铱、钌等)中筛选了铱和钌,在钛基体上进行涂覆,然后,在不同温度下烧结制备成RuO2-IrO2-TiO2/Ti阳极,并对涂层阳极的强化寿命和析氯开路电位进行了测试,采用扫描电镜(SEM)对涂层结构进行了观测分析,结果表明,RuO2-IrO2-TiO2/Ti钛基涂层阳极的最佳烧结温度为450℃,IrO2含量的最佳值为30%(摩尔百分比)。 相似文献