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991.
Bo Jiang Mian‐Shuai Yi Man‐Su Tu Shu‐Liang Wang Shu‐Jiang Tu 《Advanced Synthesis \u0026amp; Catalysis》2012,354(13):2504-2510
Brønsted acid‐promoted divergent approaches for the synthesis of multi‐functionalized fused pyrroles with different substituted patterns (44 examples) have been established. The divergent pathways were controlled by varying the charging sequence to give a series of new fused pyrroles selectively. The direct C(sp3) S bond formation was achieved for the two‐step, one‐pot reaction. 相似文献
992.
介绍了由抚顺石油化工研究院(FRIPP)开发的 FHUDS-2/FHUDS-5柴油深度加氢组合催化剂在镇海炼化新建300万 t/a 柴油加氢装置上的工业应用情况.应用结果表明: FHUDS-2/FHUDS-5催化剂组合具有良好的加氢脱硫活性和稳定性,在高空速条件下加工直馏柴油和45%左右的催化柴油、减压柴油的混合油,可以长周期稳定生产符合沪Ⅳ硫含量排放标准要求的清洁柴油产品.同时,能够加工以直馏柴油为原料生产符合欧Ⅴ排放标准要求的清洁柴油产品. 相似文献
993.
采用浸渍法制备出3种MgO负载型过渡金属催化剂Fe/MgO、Co/MgO和Ni/MgO,系统研究了甲醇在3种催化剂上于600℃下的裂解产物。结果表明,3种催化剂均能催化甲醇裂解产生富氢气体,同时产生碳纳米管。其中,Ni/MgO具有最佳的催化效果。 相似文献
994.
995.
介绍了某重整装置由于进料中硫、水超出进料标准而导致的生产波动事件,通过对反应温度、催化剂运行数据记录和分析,分析了硫、水对重整催化剂的影响,进而导致对重整反应的影响;同时提出了进料中硫、水超标发生后,重整装置应该采取的应对措施。 相似文献
996.
The hydrosilylation of cyclohexanone and acetone with triethysilane and diphenysilane catalyzed by polymer‐supported Rh(I) complex has been investigated. Two terpolymers of styrene, divinylbenzene, and 1‐vinylimidazole (S/DVB/VI) or N‐vinylpyrrolidinone (S/DVB/NVP) were used as the catalysts supports. Physical characterization of these materials has involved the measurements of the structural parameters in the dry and swollen states by DSC, the nitrogen BET adsorption method and inverse steric exclusion chromatography ISEC. From these results it can be concluded that the original polymer structure has been changed during the complex attachment giving rise to materials of higher porosity. X‐ray photoelectron spectroscopy XPS, IR, and AAS spectroscopy were used to characterization of heterogeneous complexes before and after use. The effect of the morphology of the support on the catalytic properties of the polymer‐supported Rh(I) species was tested in the hydrosilylation of ketones and correlated with the reaction mechanism. It was demonstrated that the high selectivity of homogeneous rhodium complex toward the silyl ethers can be partially reversed to the dehydrogenative silylation products by a proper choice of polymer support with favorable microporous structure. Recycling tests demonstrated high stability of the supported catalysts during prolonged use. The constant selectivity of the supported catalysts demonstrated during recycling experiments showed that they could be useful for practical application. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
997.
998.
Maijia Liao Jianyong Feng Wenjun Luo Zhiqiang Wang Jiyuan Zhang Zhaosheng Li Tao Yu Zhigang Zou 《Advanced functional materials》2012,22(14):3066-3074
Despite the fact that Ta3N5 absorbs a major fraction of the visible spectrum, the rapid decrease of photocurrent encountered in water photoelectrolysis over time remains a serious hurdle for the practical application of Ta3N5 photoelectrodes. Here, by employing a Co3O4 nanoparticle water oxidation catalyst (WOC) as well as an alkaline electrolyte, the photostability of Ta3N5 electrode is significantly improved. Co3O4/Ta3N5 photoanode exhibits the best durability against photocorrosion to date, when compared with Co(OH)x/Ta3N5 and IrO2/Ta3N5 photoanodes. Specifically, about 75% of the initial stable photocurrent remains after 2 h irradiation at 1.2 V vs. RHE (reversible hydrogen electrode). Meanwhile, a photocurrent density of 3.1 mA cm?2 has been achieved on Co3O4/Ta3N5 photoanode at 1.2 V vs. RHE with backside illumination under 1 sun AM 1.5 G simulated sunlight. The reason for the relatively high stability is discussed on the basis of electron microscopic observations and photoelectrochemical measurements, and the surface nitrogen content is monitored by X‐ray photoelectron spectroscopic analysis. 相似文献
999.
Lipid Oxidation Potential of Beef, Chicken, and Pork 总被引:5,自引:0,他引:5
Beef and pork longissimus dorsi and semimembranosus muscles and chicken breast and thigh muscles were excised 24 hr postmortem from carcasses of marketweight grain-finished feedlot beef cattle, marke-tweight hogs on a typical finishing diet, and broilers on a commercial grain diet. Muscle samples were immediately ground and formed into patties and stored raw or after cooking, at 4°C (cooked) or ?20°C (raw and cooked). TBA values (on sample weight basis) of frozen raw samples were higher for beef and pork than for chicken, as was heme iron content. However, TBA values of cooked samples were highest for chicken thigh muscles, which contained the most polyunsaturated fatty acids, at all storage temperatures. 相似文献
1000.