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91.
Disposable Australian iron-slurry (AL) and NiO-MoO3-Al2O3 (NiMo) catalysts were used in hydrocracking experiments to convert Marlim vacuum residue (ML-VR) in a slurry-bed continuous flow reactor at temperatures of 440-460 °C, under a hydrogen pressure of 14.7 MPa and an LHSV of 0.5. The degree of conversion ranged from 54 to 83%, depending on the reaction temperature and catalyst used, with AL giving more complete conversion than NiMo. AL also proved more active in the removal of nickel. Hydrogen consumption was linearly correlated with conversion regardless of the catalyst used. 相似文献
92.
本文主要介绍了网络广告的主要形式,提出了评价网络广告效果的几种方法,如比较法、加权计算法、点击率、转换率,目的在于更加全面地、科学地评价网络广告给企业带来的经济效果。 相似文献
93.
94.
首先介绍了数据字典等数据转换系统的技术基础,然后重点介绍了数据转换系统将符合数据字典要求的DWG格式地形图转换成GeoDataBase(Access)格式的地理信息系统数据库各功能模块的设计与实现,最后介绍了该系统成果。 相似文献
95.
Hydrothermal electrolysis of organic compound in the presence of electrolyte was conducted for a woody biomass model compound. The reaction behavior of 1-butanol as a woody biomass model compound was studied in subcritical conditions at 200-250 °C and 8-12 MPa with a batch autoclave. The autoclave volume was 500 mL and equipped system with agitation stirrer, electric current control, electric heating and temperature control and a pressure gauge. The chemical species in aqueous products were identified by gas chromatography mass spectrometry (GC-MS) and quantified using gas chromatography flame ionization detector (GC-FID). The gaseous products were analyzed by gas chromatography with a thermal conductivity detector (GC-TCD). The effects of reaction temperature, pressure and applied constant current on the conversion process of 1-butanol were presented. The main products from the conversion of 1-butanol were butanal, butyric acid, hydrogen and carbon dioxide. Additionally, the values of reaction rate constant for butanal and butyric acid formation were calculated at 200 and 250 °C by kinetic study. 相似文献
96.
一种U 波段鳍线单平衡混频器的设计 总被引:1,自引:0,他引:1
本文介绍了一种U 波段鳍线单平衡混频器的设计过程并给出了测试结果。混频器使用M/A-COM 公司的肖特基势垒二极管MA4E2037,整个电路制作在一块厚度为0.127mm 的RT-Duroid 5880 软基片上。射频端口采用鳍线过渡,本振端口通过波导-微带探针过渡,中频通过SMA 接头输出。测试结果显示,鳍线悬置微带线结构的混频器在本振为42 GHz,
射频在40~60GHz 范围内变化时,其变频损耗小于8.71 dB,本振到射频的隔离度大于25dB。 相似文献
97.
Li Chun 《Electrochimica acta》2010,55(9):3089-17330
Hematite (α-Fe2O3) nanoflakes and nanocubes were synthesized by liquid-solid-solution method and their properties as anode electrode materials for rechargeable Li+-ion batteries were measured. When changing the water to ethanol volume ratio in the synthesis system, the nanocrystals can be changed from α-Fe2O3 to α-FeOOH, with shapes being tuned from nanoflakes to nanocubes, non-uniform particles and nanowires. When assembled as the anode electrode materials in rechargeable Li+-ion batteries, the hematite nanoflakes showed one more plateau in the first discharge progress of the voltage-composition curves than hematite nanocrystals with other shapes in the literature. X-ray diffraction, high-resolution transmission electron microscope and electrochemical data showed that this extra plateau came from the formation of Li2Fe3O4 nanoclusters and amorphous Li2O. This experiment showed that like sizes, shapes of nanocrystals may also affect the detailed electrochemical progress. 相似文献
98.
本文基于解读新加坡店屋的历史渊源,分析近年来新加坡店屋改造典型优秀作品,归纳总结其设计方法,同时将其与闽南地区同类店屋街区改造进行对比。吸取其先进的设计理念,结合闽南地区实际,提出旧城更新及新镇建设的设计构想。 相似文献
99.
none 《金属精饰学会汇刊》2013,91(6):330-333
AbstractThis study continues the authors’ investigation of the newly developed product KAF-09OF and concerns the preparation and characterisation of amorphous phosphate coatings on carbon steels. KAF-09OF is a liquid concentrate of ammonium and alkaline phosphates, stabilising additives – buffers, softeners, activators (both inorganic and organic), as well as surfactants – a non-ionic and an anionic detergents. Gravimetric and polarisation methods, X-ray fluorescence analysis, transmission electron microscopy, X-ray photoelectron spectroscopy and atomic force microscopy have been used to determine the effect of pH (2–6), temperature conditions (20–80°C) and agitation rate (0–2000 rev min?1) on the process of phosphating using this developed product. Coating thicknesses, compositions, structures and passivation characteristics in the phosphating baths with different concentrations of KAF-09OF have been analysed. 相似文献
100.
D. J. Carlsson M. E. Krzymien L. DeschÊ nes M. Mercier C. Vachon 《Food Additives & Contaminants》2001,18(6):581-591
Infrared (IR) spectroscopy has been used to identify and quantify the phosphite antioxidant, tris(2,4-di-tert.butylphenyl) phosphite, and its corresponding phosphate in high density polyethylene (HDPE) food trays, both in the original, commercial trays and also as a function of gamma-irradiation and post-irradiation, storage conditions. This direct method of inhibitor analysis complements time-consuming (some times non-quantitative) extraction methods, which for organo-phosphites are complicated by their facile conversion to phosphates by peroxidic impurities in the solvent. Because of the complete destruction of phosphite to give mainly phosphate at quite low gamma-irradiation doses (approximately 5 kGy) and phosphate formation during melt processing and radiation sterilization of these HDPE trays must take into account products from the irradiation of phosphate. Any residual phosphite is lost progressively in post-irradiation reactions, which are complex, producing a less than-quantitative yield of phosphate. 相似文献