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971.
介绍了广西康密劳1^#锰铁高炉大修的方案选择和装备技术及今后技术进步方向。为我国其它锰铁高炉技术改造提供了一种参照方法。 相似文献
972.
Effect of igneous activity on hydrocarbon source rocks in Jiyang sub-basin, eastern China 总被引:1,自引:0,他引:1
Dongya Zhu Zhijun Jin Wenxuan Hu Yucai Song Xiaokang Gao 《Journal of Petroleum Science and Engineering》2007,59(3-4):309-320
A 50 m thick diabase sill was found in the Paleogene black mudstone hydrocarbon source rocks in Xia38 well. Within heating aureola of the sill, optical changes of kerogen and signatures of extractable bitumens in the mudstones were investigated. Under effects of high heating rate associated with sill intrusion, the vitrinite reflectance (Ro) has an increasing tendency with decreasing distance to the sill both below and above the sill. However, only within a zone of about 15 m to the diabase sill, the vitrinite reflectance shows significant increase. Above the sill, the Ro values increase gradually from 0.6% to 1.0%, whereas below the sill, the Ro values increase dramatically from 0.8% to 3.8%. The contrasting Ro increasing patterns are attributed to the different heat transferring conditions, the relatively open system above the sill and the relatively close system below. The more mature signatures below the sill are also demonstrated by the n-alkane distribution, carbon predominance index and odd-to-even carbon number predominance of the extracted bitumens. Below the sill, the proportion of the saturated hydrocarbons in the extracted bitumens increases from 34% to 79% towards the sill contact. The bitumens in the two highest rank samples which are closest to the sill are dominated by saturated or saturated + aromatic hydrocarbons.The %20S, %αββ and %Ts biomarker parameters of the extracted bitumens are 46%, 58% and 54%, respectively, at Ro = 1.5%. At Ro = 2.6% or 3.0%, they reach to 52%, 71%, and 71%, respectively, still under or close to their corresponding equilibrium end-points. These samples of high rank, established on the basis of optical assessment (vitrinite reflectance), have less mature biomarker signatures. The remarkable disparities between optical and biomarker parameters can be ascribed to that the aromatization of kerogen to increase Ro was more favored than the isomerization of biomarker in the rapid heating scenario. 相似文献
973.
Guoxi Xie Songlin Feng Xiangqian Feng Jihao Zhu Yongqiang Li 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,264(1):103-108
Imitated GE ware was one of the most famous products of Jingdezhen porcelain field in Ming dynasty (AD 1368-1644). The exterior features of its body and glaze are very marvelous. Black foot, purple mouth and crazing glaze are the main features of imitated GE ware. Until now, the key conditions of resulting these features are not clearly identified. In order to find the critical elements for firing these features, instrumental neutron activation analysis (INAA) and wavelength-dispersive X-ray fluorescence (WDXRF) were used to determine the element abundance patterns of imitated GE ware body and glaze. The experimental data was compared with that of imitated Longquan celadon and of Longquan celadon. The analytical results indicated that Fe, Ti and Na were the critical elements. The body of imitated GE ware which contains high Fe and Ti are the basic conditions of firing its black body, black foot and purple mouth. The glaze of imitated GE ware which contains high Na is the main condition of producing its crazing glaze. Na is the critical element which enlarges the difference in expansion coefficients between the glaze and body of imitated GE ware. Furthermore, Zijin soil was added into kaolin to make the body rich in Fe and Ti. And something which was rich in Na was used to produce crazing glaze in the manufacturing process of imitated GE ware. 相似文献
974.
975.
通过对活性炭载体进行不同条件的超声波处理获得了具有不同表面化学性质的载体,使用比表面积(BET)、酸碱滴定等技术手段对载体的物理化学性质进行了表征。将经过超声波处理的活性炭载体制备成Pt/C催化剂,并将催化剂直接用于催化反应,考察了活性炭载体的不同超声波处理条件对Pt/C催化剂性能的影响。实验发现,活性炭载体经过超声波处理后,表面灰分含量、pH值和中孔孔容有较大的变化;使用经过60min超声波处理后中孔孔容较大的活性炭作为载体制备的Pt/C催化剂,在催化加氢反应性能测试中显示了最高的催化活性。在此基础上,就活性炭载体的超声波处理对Pt/C催化剂活性的影响进行了讨论。 相似文献
976.
首先通过电炉—LF精炼炉—VD精炼炉—包内球化的工艺路线获得了足够的优质铁液,然后通过选取合适的分型面、设置合理的浇注系统、设计专用的冷铁、安放足够大的保温冒口和上表面加大加工余量来去除夹渣等措施,成功生产了具有厚大断面的大型球墨铸铁铸件。 相似文献
977.
GAOHui LIYan YANGLi-ping DENGHong 《半导体光子学与技术》2005,11(2):85-88,106
Hexagonal microtube ZnO was firstly grown on single crystal p-Si (111) substrates by hydrothermal method, and fabricated Ag/n-ZnO and Au/n-ZnO Schottky junction. Schottky effective barrier heights were calculated by I-V measurement. It is confirmed that the presence of a large amount of surface states related possibly to lattice imperfections existed near the surface leads to the pinning of the surface Fermi level at 0.35 eV below the conduction-band edge. Then the fabricated Schottky barrier junctions are evaluated for their use as UV photodetectors. 相似文献
978.
虽然国内正值“十一”黄金周,但是新华社的一则唁电却给中国建筑界带来了一个噩耗。中国建筑界泰斗、全国建筑设计大师、第一届梁思成奖获得者、北京市建筑设计研究院顾问总建筑师张开济,因病医治无效,于9月28日零时5分在北 相似文献
979.
对多数室内设计而言,如何在有限空间中创造出令人惊艳的设计想像,向来是不容小觑的挑战,狭小生活环境尤其是香港设计师长久以来必须面对的基本问题。要在总面积仅39.6m^2的建筑中,创造满足工作、Party和休闲三种功能需要的空间,是本案最具挑战性之处。 相似文献
980.
Man Sig Lee Gun-Dae Lee Chang-Sik Ju Seong-Soo Hong 《Solar Energy Materials & Solar Cells》2005,88(4):389-401
Nanosized titania sol has been produced by the controlled hydrolysis of titanium tetraisopropoxide (TTIP) in sodium bis(2-ethylhexyl)sulfosuccinate (AOT) reverse micelles. The physical properties, such as surface area, crystallite size and crystallinity according to R and W0 ratio, have been investigated by TEM, XRD, BET, FT–IR, TGA and DTA. In addition, the photocatalytic decomposition of p-nitrophenol has been studied by using a batch reactor in the presence of UV light in order to compare the photocatalytic activity of prepared nanosized titania. It is shown that the anatase structure appears in the 300–600 °C calcination temperature range and the transformation of anatase into rutile starts above 700 °C. The crystallite size increases with increasing R and W0 ratio but W0 ratio shows a stronger effect on the crystallite size than R ratio. In the photocatalytic decomposition of p-nitrophenol, the photocatalytic activity is mainly determined by the crystallinity of titania. In addition, the titania calcined at 500 °C shows the highest activity on the photocatalytic decomposition of p-nitrophenol() and the pure anatase structure. 相似文献