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In this research, Ni/SiO2 catalyst was modified with different amount of Gd2O3 and characterized with temperature-programmed desorption of CO2 (CO2-TPD) and NH3 (NH3-TPD), temperature-programmed reduction with H2 (H2-TPR) and X-ray diffraction (XRD). It was found that Gd2O3-modified Ni/SiO2 catalysts possessed higher CO2 adsorption and activation ability due to the formation of surface carbonate species. H2-TPR and XRD characterizations found that the strong interaction among nickel, Gd2O3 and SiO2 took place, which improved the dispersion of Ni. Gd2O3-modified Ni/SiO2 catalysts exhibited higher activity and stability for the combined oxy-CO2 reforming of methane in fluidized-bed reactor. The H2/CO ratio in produced syngas could be controlled via controlling reaction temperature and CO2/O2 ratio in feed. 相似文献
105.
The rheological behavior, thermal properties, and molecular mobility of a series of maleic anhydride (MA) grafted high‐density polyethylenes were characterized and evaluated. The rheological behavior was studied with a Haake minilaboratory. The viscosity of the samples in their melt state decreased with an increase in the graft yield, and this could be attributed to the higher molecular mobility for samples with a higher degree of grafting. The thermal properties were investigated with dynamic mechanical analysis and differential scanning calorimetry. Positron annihilation lifetime measurements were used to study the effect of the degree of grafting on the chemical environment and the atomic‐scale free‐volume properties. It was found that the grafted MA group played a significant chemical inhibition role in positronium formation when the graft yield was low. The results also indicated that the higher the degree of grafting was, the broader the free‐volume distribution was. The relationship between the microstructure and rheological behavior is discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
106.
Hsu‐Wei Fang Hsien‐Chieh Wang Teh‐Hua Tsai Wei‐Bor Tsai Shao‐Yi Hou Hsuan‐Liang Liu Wun‐Hsing Lee Yung‐Chang Lu Chun‐Hsiung Huang 《应用聚合物科学杂志》2008,108(4):2428-2437
Wear of ultrahigh‐molecular‐weight polyethylene (UHMWPE) and wear‐particle‐induced osteolysis and bone resorption are the major factors causing the failure of total joint replacements. It is feasible to improve the lubrication and reduce the wear of artificial joints. We need further understanding of the lubrication mechanism of the synovial fluid. The objective of this study is to evaluate the lubricating ability of three major components in the synovial fluid: albumin, globulin, and phospholipids. An accelerated wear testing procedure in which UHMWPE is rubbed against a microfabricated surface with controlled asperities has been developed to evaluate the lubrication behavior. An analysis of the wear particle dimensions and wear amount of the tests has provided insights for comparing their lubrication performance. It is concluded that the presence of biomolecules at the articulating interface may reduce friction. A higher concentration of a biological lubricant leads to a decrease in the wear particle width. In addition, in combination with the wear results and mechanical analysis, the roles of individual biomolecules contributing to friction and wear at the articulating interface are discussed. These results can help us to identify the role of the biomolecules in the boundary lubrication of artificial joints, and further development of lubricating additives for artificial joints may be feasible. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
107.
论薄板坯连铸连轧产品质量优势 总被引:1,自引:0,他引:1
廖喆 《金属材料与冶金工程》2003,31(4):7-10
通过对薄板坯连铸连轧工艺的分析,深入研究了其产品的质量优势,同时还指出了在产品生产过程中需要重点注意解决的一些问题。 相似文献
108.
本文简要介绍深圳某商住楼通风空调系统、水系统的设计及空调方式的选取、简述了各项设计的技术数据,可供同行参考。 相似文献
109.
The self-assembly of various nanostructures is recently attracting a great deal of research attention. In this paper, we demonstrate that a palladium chloride aqueous solution, mixed with a proper ammonia solution, can produce Tetra-amminepalladous chloride (Pd(NH3)4Cl2·H2O) nanowires. These nanowires can spontaneously form the two-dimensional hexagon-oriented Pd(NH3)4Cl2·H2O arrays on mica surfaces. We can control the length and height of these nanowires by adjusting their deposit time on the mica substrate. This method can be potentially used in making sensors or in making templates to wire and position nanodevices. 相似文献
110.
硫含量对钴钼型耐硫脱氧剂的脱氧活性影响 总被引:2,自引:0,他引:2
研究了工艺气中硫含量对钴钼型耐硫脱氧剂脱氧活性的影响。通过常压微反 -色谱装置测定脱氧剂的本征脱氧活性 ,加压原粒度反应器测定脱氧剂的表观脱氧活性 ,结合实际经验确定了耐硫脱氧剂所需的最低硫含量。还讨论了温度、压力、空速对耐硫脱氧剂脱氧活性的影响。结果表明 ,耐硫脱氧剂完全能满足耐硫变换工艺的要求 ,而且有耐硫变换的作用 ,并对耐硫变换催化剂起到保护作用 相似文献