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931.
煤中负载氢氧化钙对催化气化和甲烷化反应的影响 总被引:1,自引:0,他引:1
煤中负载氢氧化钙对催化气化和甲烷化反应的影响 《燃料化学学报》2016,44(10):1160-1167
以不连沟次烟煤为研究对象,在加压固定床中研究Ca(OH)_2对煤气化及负载Ca(OH)_2煤热解半焦的甲烷化反应活性。结果表明,煤中添加Ca(OH)_2能够明显促进气化反应的进行和甲烷的生成,随着气化温度的升高和负载量的增加,碳转化率增加,但负载量存在饱和点。不同的催化剂负载方式对Ca的分散有一定的影响,进而影响其催化性能。含有Ca的半焦能够明显促进甲烷化的进行,出口气甲烷含量随甲烷化温度和催化剂负载量的升高而增强。采用红外光谱分析揭示了煤负载Ca(OH)_2的离子交换机理和扩散过程,这一过程影响煤气化反应性能。 相似文献
932.
Yu‐Heng Deng Jung‐Tsai Chen Chia‐Hao Chang Kuo‐Sung Liao Kuo‐Lun Tung William E. Price Yusuke Yamauchi Kevin C.‐W. Wu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(41):12985-12988
Despite much progress in the development of mixed matrix membranes (MMMs) for many advanced applications, the synthesis of MMMs without particle agglomeration or phase separation at high nanofiller loadings is still challenging. In this work, we synthesized nanoporous zeolitic imidazole framework (ZIF‐8) nanoparticles with a particle size of 60 nm and a pore size of 0.34 nm in water and directly added them into an aqueous solution of the organic polymer poly(vinyl alcohol) (PVA) without an intermediate drying process. This approach led to a high‐quality PVA/ZIF‐8 MMM with enhanced performance in ethanol dehydration by pervaporation. The permeability of this MMM is three times higher than that of pristine PVA, and the separation factor is nearly nine times larger than that of pristine PVA. The significantly improved separation performance was attributed to the increase in the fractional free volume in the membranes. 相似文献
933.
Zinc‐Catalyzed Alkyne Oxidation/CH Functionalization: Highly Site‐Selective Synthesis of Versatile Isoquinolones and β‐Carbolines
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Long Li Bo Zhou Yong‐Heng Wang Chao Shu Yi‐Fei Pan Prof. Dr. Xin Lu Prof. Dr. Long‐Wu Ye 《Angewandte Chemie (International ed. in English)》2015,54(28):8245-8249
An efficient zinc(II)‐catalyzed alkyne oxidation/C? H functionalization sequence was developed, thus leading to highly site‐selective synthesis of a variety of isoquinolones and β‐carbolines. Importantly, in contrast to the well‐established gold‐catalyzed intermolecular alkyne oxidation, over‐oxidation can be completely suppressed in this system and the reaction most likely proceeds by a Friedel–Crafts‐type pathway. Mechanistic studies and theoretical calculations are described. 相似文献
934.
We provide a family of general monogamy inequalities for global quantum discord (GQD), which can be considered as an extension of the usual discord monogamy inequality. It can be shown that those inequalities are satisfied under the similar condition for the holding of usual monogamy relation. We find that there is an intrinsic connection among them. Furthermore, we present a different type of monogamy inequality and prove that it holds under the condition that the bipartite GQDs do not increase when tracing out some subsystems. We also study the residual GQD based on the second type of monogamy inequality. As applications of those quantities, we investigate the GQDs and residual GQD in characterizing the quantum phase transition in the transverse field Ising model. 相似文献
935.
利用磁控溅射技术,在柔性基材PET上沉积AgCu合金制备的NSN系列隔热膜,继承了单Ag隔热膜良好的光谱选择性,同时能有效的解决Ag易硫化的难题.通过选择合适的AgCu合金靶材、NSN70隔热膜的膜系设计与制备、样品的形貌检测、耐候性实验、光学性能测试等多方面研究了NSN隔热膜.实验结果为以后大规模工业化生产NSN系列隔热膜奠定基础. 相似文献
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938.
Two conjugated polymers HXS-1 and PDFCDTBT were prepared by direct C–H activation and Suzuki polycondensation and their chemical structures were characterized by 1H NMR spectroscopy.The molecular weight of conjugated polymer synthesized by direct C–H activation is lower than the corresponding polymers prepared by Suzuki polycondensation.Conjugated polymers synthesized by direct C–H activation have considerable solubility in common organic solvents and form amorphous film.The photovoltaic property of conjugated polymers synthesized by direct C–H activation is inferior to the corresponding polymers synthesized by Suzuki polycondensation. 相似文献
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