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101.
102.
用电子自旋共振波谱方法研究了半导体超微粒子表面光诱导电子转移所引发的底物的次级自由基反应动力学过程.结果表明,用含有水溶性草酸盐的硫化镉(CdS)胶体体系产生的COO·-离子基,可以较方便地引发其它自由基反应,并根据已知的由DMPO捕捉COO·-的反应速度常数数据,去计算COO·-基与其它可产生稳定自由基的化合物进行反应的速度常数值,从而在此基础上发展了一种研究自由基反应动力学的行之有效的简便的新途径和新方法,可以较广泛地应用于其它凝聚相的自由基反应动力学体系的研究. 相似文献
103.
Catalin Florin Petre Abdelaaziz Azizi Caroline Olsen Abdelaziz Baçaoui Faïçal Larachi 《Journal of separation science》2008,31(22):3902-3910
A capillary electrophoretic protocol for the separation and quantification of the most important species potentially liberated during the cyanidation of gold sulfide‐rich ores was accomplished in this study. The separation of 11 ions: S2O32–, Cu(CN)32–, Fe(CN)64–, Fe(CN)63–, SCN–, Au(CN)2–, Ag(CN)2–, SO42–, OCN–, SO32–, and HS– was achieved using an indirect UV detection method. The robustness of the analytical protocol was tested by analyzing ions speciation during the cyanidation of two gold sulfide‐rich ores. The 1‐h cyanidation of the two ores released up to six complexes into solution: S2O32–, Cu(CN)32–, SCN–, Fe(CN)64–, OCN–, and SO42–. The mineralogy of the ore was found to influence directly the nature and the amount of the dissolved species. Conserving the cyanidation solution for 72 h after sampling resulted in 96% total sulfur recovery. These results allow us to conclude that the analytical protocol developed in this study can become very useful for the optimization of precious‐metals cyanidation plants. 相似文献
104.
105.
报道了一个在聚乙二醇中由卤代芳烃合成不同二芳基硫化物的高效方法.在Cu催化剂作用下,无味、易得、稳定的Na2S2O3· 5H2O盐是有效的硫源. 相似文献
106.
This Letter reports an environmentally-friendly one-pot SNAr reaction of thiols to 4-halobenzoic acid methyl esters to provide 4-substituted sulfone benzoic acids and picolinic acids after bleach-mediated oxidative workup. These acid intermediates were synthesized on gram scale, are perfect partners for library synthesis, and have good physical chemical properties useful for drug discovery. 相似文献
107.
《合成通讯》2013,43(18):3367-3372
Abstract The report that oxidation of sulfides to sulfoxides using tetrabutylammonium peroxydisulfate (2) in methylene chloride was found to be erroneous. We repeated the procedure described in the paper and found that oxidation of sulfide to sulfoxide could not be achieved with the method. 相似文献
108.
Hao-Hua Deng Shao-Huang Weng Shuang-Lu Huang Ling-Na Zhang Ai-Lin Liu Xin-Hua Lin Wei Chen 《Analytica chimica acta》2014
Colorimetric recognition and sensing of sulfide with high sensitivity was proposed based on target-induced shielding against the peroxidase-like activity of bare gold nanoparticles. Significant features of the new assay system are its simplicity and cost-effectiveness. The recognition of sulfide by bare gold nanoparticles can be fulfilled in a few seconds and the assay can be accomplished in about 10 min. Furthermore, the new assay system does not require surface modification of GNPs to obtain the specificity for sulfide, and a salt-induced aggregation step is not needed. The detection limit of this method for sulfide was 80 nM. These features make this sensor a potentially powerful tool for the quantitative determination of sulfide in water samples. 相似文献
109.
Although a number of methods have been developed for the selective oxidation of sulfides to sulfoxides, the need remains for alternative efficient, reliable strategies that can be generally applied to various sulfides and that use readily available reagents under mild reaction conditions. Herein, we report the use of urea–hydrogen peroxide adduct (UHP) and cyanuric chloride in CH3CN at room temperature to convert sulfides to sulfoxides in excellent yields. In particular, this protocol produced sulfoxides with aromatic rings bearing electron-withdrawing groups in excellent yields. 相似文献
110.
Development of an Amperometric Microbial Biosensor Based on Thiobacillus thioparus Cells for Sulfide and Its Application to Detection of Sulfate‐Reducing Bacteria 下载免费PDF全文
This paper describes a novel electrochemical microbial biosensor based on Thiobacillus thioparus cells for sulfide detection. The morphology and electrochemical properties of the proposed biosensor were characterized by SEM and cyclic voltammetry, respectively. Working conditions of the microbial biosensor were optimized to obtain good electrochemical performances. Under the optimum conditions, analytical performances were evaluated, and the results suggested that the microbial biosensor could be used for selective detection of sulfide. The microbial biosensor was then successfully applied in detection of sulfate‐reducing bacteria by oxidizing its characteristic metabolite, sulfide, which was accumulated in culture media during bacterial growth. 相似文献