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991.
Yan Su Shuping Wang Tongying Zhang Shurong Wang Baolin Zhu Jianliang Cao Zhongyong Yuan Shoumin Zhang Weiping Huang Shihua Wu 《Catalysis Letters》2008,124(3-4):405-412
Two series of Cu–Ce–O and Cu–Co–Ce–O catalysts were prepared by co-precipitation method. The prepared catalysts were characterized by XRD, IR, TPR, XPS, BET and ICP-AES. The catalytic activities of the catalysts for low-temperature CO oxidation were evaluated through a microreactor-GC system. TPR results indicate that the addition of cobalt to the Cu–Ce–O can increase the dispersion of copper oxide, and the interaction between cobalt and copper can enhance the reducibility of each other. XPS analysis show that Ce4+, Cu2+, along with Co3O4, are present on the surface of Cu0.4Co0.6Ce4 catalyst. The Co/Cu atomic ratio and the calcination temperature have significant effect on the activities of the catalysts. Compared with Cu1Ce4 catalyst, the Cu0.4Co0.6Ce4 catalyst has better activity and thermal stability. 相似文献
992.
Yan Xia Guang Lu Han Qiu Gen Zhang Yi Gong Ian Broadwell Qing Lin Liu 《应用聚合物科学杂志》2013,130(5):3718-3725
CuO‐filled aminomethylated polysulfone hybrid membranes were prepared for sulfur removal from gasoline. The as‐prepared membranes were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X‐ray diffraction (XRD). The separation performance of the hybrid membranes was evaluated by pervaporation (PV) separation of n‐heptane/thiophene binary mixture. CuO‐filling leads to a decrease in permeation flux. The sulfur‐enrichment factor increased first and then decreased with increasing CuO loading, and it is worth noting that there is a rebound in enrichment factor above 8 wt % CuO loading. Influencing factors such as nitrogen content, feed temperature, sulfur content, and various hydrocarbons on membrane PV performance were also evaluated. Permeation flux of 23.9 kg·μm·m?2·h?1 and sulfur‐enrichment factor of 3.9 can be achieved at 4 wt % CuO loading in PV of n‐heptane/thiophene binary mixture with 1500 μg·g?1 sulfur content. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3718–3725, 2013 相似文献
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994.
995.
A series of optically active 3-(9-alkylfluoren-9-yl)propene oxides were synthesized by the reaction of 9-alkylfluoren-9-yllithium with the optically active epichlorohydrin at −70 °C and polymerized using KOH as an initiator. The molecular weight of the poly(3-(9-alkylfluoren-9-yl)propene oxide)s is larger than that of poly(4,4,4-triphenyl-1-butene oxide), which had been proved to take stable helical conformation in solution, and their molecular weight distributions were narrower (Mw/Mn = 1.02 to 1.09) than poly(4,4,4-triphenyl-1-butene oxide). By investigating of chiroptical properties of a series of polymers derived from optically active epoxide, it is suggested that the poly(3-(9-alkylfluoren-9-yl)propene oxide)s keep one-handed helical conformation in solution. 相似文献
996.
997.
3表面张力引起的涂层弊病[3~5]表面张力引起的涂层弊病在溶剂型涂料中更为常见。在水性涂料中 ,由于总是采用表面活性剂 ,使涂料的表面张力较为恒定 ,弊病产生的起因与表面张力的关系相对较少。3.1对流窝 (贝纳尔德窝 )当溶剂在湿涂层表面挥发时 ,将产生两种作用 :即由于溶剂挥发时吸热 ,使挥发中心附近温度降低 ;另外挥发中心附近的颜料和成膜物的浓度增大。这两种作用都使挥发中心附近的表面张力增大 (2.1中液体表面张力随温度升高而降低 )。这样 ,挥发中心四周的涂料有比中心处更高的表面张力 ,形成从中心向外的拉力 (见图3… 相似文献
998.
高温陶瓷材料延迟断裂寿命预测:Knoop压痕小裂纹技术 总被引:4,自引:0,他引:4
本文对Knoop压痕小裂纹技术在陶瓷材料寿命预测研究中的应用进行了简要的评述,并举出具体的寿命预测实例说明了这一技术的实用性。 相似文献
999.
使用瞬态NO气体分析仪,结合其它发动机参数,研究缸内燃烧过程.试验结果表明NO排放可以成为判断缸内燃烧的新依据.冷起动过程中瞬态NO排放主要集中在初始的几个循环中,而发动机转速稳定后,后续循环瞬态NO排放逐渐降低.冷起动过程中,混合气浓度保持不变时,瞬态NO排放随点火角度的提前而增加. 相似文献
1000.
Xiuxia Meng Xun Gong Yimei Yin Nai-Tao Yang Xiaoyao Tan Zi-Feng Ma 《International Journal of Hydrogen Energy》2013
YSZ/NiO-YSZ dual-layer hollow fibers with a thin YSZ top layer integrated on a porous NiO-YSZ (60:40 in weight) support, have been developed by one step method via a co-spinning-sintering process. Hydrogen reduction was performed to form YSZ/Ni-YSZ micro tube as the half solid oxide fuel cells (SOFCs). The microstructure of the dual-layer hollow fibers was tailored by adding ethanol as non-solvent in the initial mixture dopes for NiO-YSZ anode spinning. LSM cathode containing 20 wt%-YSZ was deposited on the electrolyte surface by dip-coating method to fabricate micro-tubular SOFCs. Experimental results indicate that the dual-layer hollow fibers from the anode dopes containing 15–20 wt% of ethanol possess the desired microstructure with optimized properties, such as the bending strength of 180 MPa, the porosity of 38–35% and the conductivity of 3000 S cm−1 at room temperature. The micro-tubular SOFCs fabricated from such hollow fibers show a maximum power density up to 485 mW cm−2 at 850 °C with 20 mL min−1 of H2 as fuel and 30 mL min−1 air as oxidant, respectively. 相似文献