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991.
992.
1 前 言 随着国家能源结构的调整,我国天然气产量在不断增加。天然气作为一种清洁、高效的能源,在各领域都得到了充分的发展和利用。随着天然气价格的不断下调,玻璃工业将会越来越广泛地使用天然气。本文主要探讨玻璃熔窑天然气燃烧的有关问题。 相似文献
993.
重组G145R HBsAg亲和纯化方法的建立及其应用 总被引:2,自引:0,他引:2
目的建立重组乙型肝炎病毒G145R变异HBsAg抗体亲和纯化方法。方法用抗-HBs单克隆抗体(D12- McAb)制备亲和层析胶,对2A8细胞(分泌G145R变异HBsAg)培养上清盐析物进行亲和纯化。采用SDS-PAGE、Western blot及ELISA,对纯化产物的纯度、特异性、含量和回收率进行鉴定,并与同法纯化的HBsAg阳性血清及r-wHBsAg提取物进行比较。结果D12-McAb对重组真核表达G145R变异HBsAg、HBsAg阳性血清及r-wHBsAS三者具有相似的亲和性,产物纯度分别为90.3%、95.2%和93.1%,回收率分别为43.3%、72.0%和66.4%。结论已成功地建立了重组G145R变异HBsAg抗体亲和纯化方法,为G145R变异以及其他HBV免疫逃逸变异感染的深入研究奠定了重要的技术基础。 相似文献
994.
995.
Lianjun Wang Wan Jiang Lidong Chen Mei Yang Hongmin Zhu 《Journal of the American Ceramic Society》2006,89(7):2364-2366
Nano-sized TiN powders with an average particle size of 19 nm were synthesized via a new method, reduction–nitridation reaction in liquid ammonia. A consolidation procedure using spark plasma sintering (SPS) was used, and a dense TiN ceramic (>98% of theoretical) with mean grain size of 100–150 nm was obtained at 1380°C. The influence of sintering temperature on grain growth and microstructural evolution was also discussed. 相似文献
996.
Preparation of Titanium Nitride/Alumina Laminate Composites 总被引:2,自引:0,他引:2
Jing-Xian Zhang Zheng-Ren Huang Dong-Liang Jiang Shouhong H. Tan Zhijian Shen Mats Nygren 《Journal of the American Ceramic Society》2002,85(5):1133-1138
A preparation route for TiN/Al2 O3 laminate composites has been described. A water-based process using Al2 O3 and TiN slurries with solids contents of 40 and 35 vol%, respectively, was used to make TiN and Al2 O3 tapes. The removal of the binder was monitored by weight-loss measurements in a thermogravimetry unit. Bodies composed of Al2 O3 and TiN tapes were densified at temperatures of 1400° and 1500°C using the Spark Plasma Sintering® (SPS) technique. Densities of >98% of the theoretical densities were approached. Crack-free and almost fully densified TiN/Al2 O3 compacts were prepared by heating the burned-out green bodies to the final sintering temperature (1500°C) at a rate of 100°C/min, and with a holding time of 5–10 min, under a pressure of 75 MPa. The microstructures of the obtained compacts were studied using scanning electron microscopy. Grain sizes in the sintered Al2 O3 and TiN compacts were similar to those of the precursor powders. Hardness and indentation fracture toughness were measured at room temperature, and the monolithic compacts as well as the laminate composites exhibited anisotropic mechanical behavior; i.e., the cracks propagated much more easily in a direction parallel to the laminas than perpendicular to them. 相似文献
997.
悬浮污泥过滤工艺在油田污水深度处理中的应用 总被引:3,自引:0,他引:3
对大庆油田石英砂过滤器结构进行改造,并应用悬浮污泥过滤技术对油田污水进行了深度处理,试验取得了良好的处理效果.改造后的石英砂过滤器在进水悬浮物质量浓度为40~63 mg/L时,出水悬浮物质量浓度小于10 mg/L,平均去除率为81.8%,比改造前提高了33.3%;在进水油质量浓度为79~119 mg/L时,出水油质量浓度小于10 mg/L,平均去除率为92.9%,比改造前提高了21.2%.通过悬浮污泥过滤工艺处理后,出水悬浮物质量浓度小于2 mg/L,出水油质量浓度小于3 mg/L,滤出水悬浮物去除率达到96.4%,油去除率达到97.0%,水质均达到油田回注水标准. 相似文献
998.
999.
Bo Hyun Ryu Sang Yup Lee Dong Hyun Lee Gui Young Han Tae-Jin Lee Ki June Yoon 《Catalysis Today》2007,123(1-4):303-309
Carbon black has recently been reported to act as an effective catalyst for methane decomposition and to exhibit stable catalytic behavior despite carbon deposition, and thus it can be used for CO2-free production of hydrogen from natural gas. In this work, various carbon blacks with different primary particle size were investigated with respect to methane decomposition under atmospheric pressure from 1123 to 1223 K. Catalytic characteristics, such as activity, activation energy and reaction order, were investigated and compared. It was observed that with decreasing primary particle size (or increasing specific surface area), the specific activity increased and the activation energy decreased. The reaction orders for various pelletized, rubber-reinforcing carbon blacks were 0.6–0.7, about the same regardless of the primary particle size, while they were near 1 for fluffy carbon blacks. Fluffy carbon black showed higher activity and activation energy than the pelletized carbon black of the same primary particle size. Changes of the surface morphology during carbon deposition were observed by TEM. Variations of the number of active sites were discussed in regard of the primary particle size, carbon deposition and binder. The presence of different types of active sites was also suggested. 相似文献
1000.