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31.
Ashok K. Vijh 《Drying Technology》1995,13(1):215-224
An attempt is made to elucidate the electrochemical aspects of the electroosmotic dewatering (EOD) of clays as reported in some recent work, especially that on interrupted DC power electroosmotic dewatering published by Rabie, Mujumdar and Weber (2). These authors showed that the dewatering by EOD stops after the DC power has been on for several minutes or hours; on interruption of their power and on short-circuiting of the electrodes, conditions can be created again for some further dewatering by DC power EOD. This discovery, of Rabie et al. is interpreted as a fuel cell effect and it is shown that it affords clues to several other electrochemical strategies for the possible enhancement of the efficiency of the EOD by DC power.
Further, the open circuit potentials observed by Rabie et al. (2) on the interruption of DC power are given an electrochemical interpretation which leads to quantitative estimates in agreement with the experimental values. 相似文献
Further, the open circuit potentials observed by Rabie et al. (2) on the interruption of DC power are given an electrochemical interpretation which leads to quantitative estimates in agreement with the experimental values. 相似文献
32.
防腐涂料及涂装技术讲座系列介绍防腐蚀涂料的品种和各类应用及最新产品研究进展。本讲主要介绍涂装前的表面预处理方法及表面处理质量的评定等 相似文献
33.
概述了高压放大器的基本组成,以及采用高压稳压电源措施,提高高压放大器的性能,并简述了高压放大器输出级的工作原理,给出了过渡保护方法。 相似文献
34.
高发射率节能涂料及其应用 总被引:19,自引:0,他引:19
讨论了高发射率涂料节能的条件,了一种在1000℃仍保持高发射率的优质涂料,并解决了涂料与金属基体的粘结工艺,用此涂料制成增强辐射电阻带和复合炉衬,得到的新炉比旧炉节能20-40%。 相似文献
35.
36.
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
37.
Shou-ren Wang Hao-ran Geng Lin-hai Hui Ying-zi Wang 《Journal of Materials Engineering and Performance》2007,16(1):113-118
A multiphase reticulated porous ceramic (RPC) as Si3N4–Al2O3–SiO2 was fabricated by replication techniques. Proper volumes of additives and twice sinter- twice immerse process endow the RPC
an excellent crack healing and submerging property. The compressive strength and fracture toughness improved owing to the
crack bridging behavior. The existence of pores in struts in RPC blunt the crack tip and increased the external force needed
to propagate the crack. The mechanisms play a beneficial role in enhancing the compressive strength and fracture strength.
Si3N4 RPC with additives of 5%Al and 5% Al2O3 yielded the compressive strength of 9.8 MPa and fracture toughness of 0.3 MPa m1/2. 相似文献
38.
介绍一种新型的恒通量的微滤膜———ISOFLUX 膜 ,该种膜的膜通量衰减比通常的微滤膜要小得多 ,对ISOFLUX 膜的原理和数学模型进行了推导 ,并给出了对牛奶进行冷杀菌过滤的结果 . 相似文献
39.
采用化学共沉淀法作为钴蓝颜料的制备方法,探讨了主要工艺因素对制备钴蓝颜料性能的影响,对制备的样品进行了测试与表征。结果表明:Co2+和Al3+物质的量比为1∶2.5时,制备的钴蓝样品颜色饱和度与明度最高,沉淀剂为尿素时制得的样品的粒度最小,粒度分布比较均匀。前驱体的洗涤过程采取水洗加醇洗的方法可有效减少样品的硬团聚现象,且前驱体的最佳煅烧温度为950℃左右。 相似文献
40.
Dario Pasini Luigi Garlaschelli Elza Bontempi Laura E. Depero 《Fullerenes, Nanotubes and Carbon Nanostructures》2007,15(5):367-378
The synthesis of a series of polymers and cyclopolymers bearing crown ethers of differing structure and affinities towards primary ammonium ions is discussed. These polymers have been tested in their efficiency to form structurally homogeneous thin films when blended with an amphiphilic C60 compound containing a primary ammonium ion functional group. The X-ray reflectivity characterization of the films revealed that the polymer bearing the crown ether with the least affinity for primary ammonium ions, but having the highest degree of polymerization, is the most effective in forming structurally homogeneous thin films. 相似文献