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11.
Hydrate formation rate plays an important role in making hydrates for the storage and transport of natural gas. Micellar surfactant solutions were found to increase gas hydrate formation rate and storage capacity. With the presence of surfactant, hydrate could form quickly in a quiescent system and the energy costs of hydrate formation reduced. Surfactants (an anionic surfactant, a non‐ionic surfactant and their mixtures) and liquid hydrocarbons (cyclopentane and methylcyclohexane) were used to improve hydrate formation. The experiments of hydrate formation were carried out in the pressure range 3.69–6.82 MPa and the temperature range 274.05–277.55 K. The experimental pressures were kept constant during hydrate formation in each experimental run. The effect of anionic surfactant (sodium dodecyl sulphate (SDS)) on natural gas storage in hydrates is more pronounced compared to a non‐ionic surfactant (dodecyl polysaccharide glycoside (DPG)). The induction time of hydrate formation was reduced with the presence of cyclopentane (CP). Cyclopentane and methylcyclohexane (MCH) could increase hydrate formation rate, but reduced hydrate storage capacity The higher methylcyclohexane concentration, the lower the hydrate storage capacity. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
12.
介绍了用自然澄清法降低、回收旋涡炉渣中的铜的方法。该方法工艺简单。操作方便,不仅降低冶炼成本,同时提高了经济效益。 相似文献
13.
介绍了Shell渣油气化装置将渣油原料改为天然气时控制系统的改造方案。提出的改造思路不但可用于Shell渣油气化,也可用于德士古渣油气化的油改气工程中。 相似文献
14.
某铅锌矿选矿尾矿综合利用试验研究 总被引:2,自引:0,他引:2
针对选矿尾矿的特性,采用高选择性的3ACH捕收剂、F—1抑制剂,回收了绢云母含量分别达96%和64%以上的一、二级绢云母产品。经应用试验表明:绢云母一级品在橡胶中的补强性能基本达到了沉淀法白炭黑水平,二级品也全面超过硅铝炭黑的补强性能。 相似文献
15.
随着汽车数量的迅速增加,汽车排放的有害废气也急剧增加,人们的健康受到威胁,解决这一问题的最好办法是发展清洁代用燃料汽车。介绍了天然气汽车和液化石油气汽车的主要优点,分析了目前我国清洁代用燃料汽车的发展现状,阐述了近期适宜发展我国清洁代用燃料汽车的机遇和面临的困难。最后就提高人们的环保意识、修改和完善汽车尾气污染控制法及排放标准、清洁代用燃料汽车的有关标准和安全措施。对发展这种汽车应给予优惠政策以及零部件生产和车辆改装企业的管理等方面,提出了建议。 相似文献
16.
E. M. Abdel-Bary H. H. Hassan A. M. El-Lawindy M. K. Abu-Assy F. K. El-Tantawy 《Polymer International》1993,30(3):371-374
Butyl rubber mixtures loaded with 70 phr general purpose furnace black (GPF) and tetramethyl thiuram disulphide (TMTD)/S as vulcanizing system were prepared. The kinetics of their electrical conductivity development during the vulcanization process were followed by using an especially devised system. It was found that the increase in the electrical conductivity during vulcanization obeys an exponential growth function with time constant τ, which markedly decreases with increasing vulcanization temperature as well as with the efficiency of the vulcanizing system. After completion of the vulcanization process, about 80 min, the samples obtained possess reasonable stability and reproducibility of electrical conductivity. 相似文献
17.
Toru Ikegami Hideyuki Negishi Dai Kitamoto Keiji Sakaki Tomohiro Imura Masayoshi Okamoto Yasushi Idemoto Nobuyuki Koura Tsuneji Sano Kenji Haraya Hiroshi Yanagishita 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(4):381-387
In order to produce highly concentrated bioethanol by pervaporation using an ethanol‐permselective silicalite membrane, techniques to suppress adsorption of succinic acid, which is a chief by‐product of ethanol fermentation and causes the deterioration in pervaporation performance, onto the silicalite crystals was investigated. The amount adsorbed increased as the pH of the aqueous succinic acid solution decreased. The pervaporation performance also decreased with decreasing pH when the ternary mixtures of ethanol/water/succinic acid were separated. Using silicalite membranes individually coated with two types of silicone rubber, pervaporation performance was significantly improved in the pH range of 5 to 7, when compared with that of non‐coated silicalite membranes in ternary mixtures of ethanol/water/succinic acid. Moreover, when using a silicalite membrane double‐coated with the two types of silicone rubber, pervaporation performance was stabilized at lower pH values. In the separation of bioethanol by pervaporation using the double‐coated silicalite membrane, removal of accumulated substances having an ultraviolet absorption maximum at approximately 260 nm from the fermentation broth proved to be vital for efficient pervaporation. Copyright © 2005 Society of Chemical Industry 相似文献
18.
从理论计算分离器处理能力和现场开展试验两方面入手,对靖边气田目前在用的不同规格分离器的分离效果进行了对比分析,通过对现场数据统计和整理,得到了靖边气田不同规格分离器合理的处理气量,给气田开发建设中分离器的选型和维护改造中分离器的调整提供了依据。 相似文献
19.
Eva M. Valero Juan L. Nieves Sérgio M. C. Nascimento Kinjiro Amano David H. Foster 《Color research and application》2007,32(5):352-360
Many spectral‐recovery methods using RGB digital cameras assume the underlying smoothness of illuminant and reflectance spectra, and apply low‐dimensional linear models. The aim of the present work was to test whether a direct‐mapping method could be used instead of a linear‐models approach to recover spectral radiances and reflectances from natural scenes with an RGB digital camera and colored filters. In computer simulations, a conventional RGB digital camera with up to three colored filters was used to image scenes drawn from a hyperspectral image database. Three measures were used to evaluate recovery with the direct‐mapping method: goodness‐of‐fit, root‐mean‐square error, and a color‐difference metric. It was found that with two and three filters both spectral radiances and reflectances could be recovered sufficiently accurately for many practical applications. With little increase in computational complexity, an RGB camera and a few colored filters can provide significantly better recovery of natural scenes than an RGB camera alone. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 352–360, 2007 相似文献
20.