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991.
992.
该文通过水质调查和大量实验数据,对循环水改为黄河水质运行的配方进行了筛选,并提出了自然pH全有机配方的概念,通过监测数据,对黄河水配方运行情况进行了总结,该配方投用后,不但能节约地下水资源,而且经济效益显著。 相似文献
993.
PVC生产中的二次水回收工艺改造 总被引:2,自引:0,他引:2
介绍了在PVC生产过程中产生的蒸汽冷凝水、压滤水、废自来水、母液水的回收和综合利用的情况。工艺改进后,青岛海晶化工集团有限公司12万t/a PVC装置可节水67万t/a,节约资金204万元/a。 相似文献
994.
Hua Zhao 《Chemical Engineering Communications》2006,193(12):1660-1677
Over the past decade, ionic liquids (ILs) have become one of the fastest growing “green” media for chemists and engineers due to their superb physicochemical properties. The applications of these remarkable salts in reactions and extraction processes have been extensively investigated and reviewed. This review, however, highlights recent advances of ILs as versatile “green” engineering liquids in a variety of industrial applications including heat transfer fluids, azeotrope-breaking liquids, lubricants, electrolytes, liquid crystals, supported IL membranes, plasticizers, and more. This review is not intended to be comprehensive, but rather to discuss the potentials of ILs for diverse industrial applications. 相似文献
995.
With the aim of obtaining RO membranes for brackish water desalination from purified celluloses (cotton linters and bleached bagasse pulp), two reactions (heterogeneous and homogeneous) were applied for the synthesis of cellulose acetate (CA). The efficiency of the membranes was measured and compared with those prepared from purchased CA and prepared CA by acetylation of imported high-grade viscose wood pulp. The effect of blending CA with polypropylene (PP), on the efficiency of the prepared RO membranes was also studied. Results showed that the method of preparation of CA plays a profound effect on the salt rejection and water flux of the RO membranes. The efficiencies of RO membranes formed from heterogeneously acetylated celluloses are higher than those prepared from homogeneous ones. Blending the acetylated cellulose with 9% PP wastes improves the efficiency of membranes prepared from the homogeneously acetylated celluloses. 相似文献
996.
The characteristic feature of this cooling tower water treatment is the intermittent addition of ozone for several days. 相似文献
997.
论述了金属的电化学腐蚀和外加电流阴极保护原理。说明对以海水为介质的冷却、冷凝设备,采用外加电流阴极保护是防止设备腐蚀的有效方法。举例说明了应用效果。 相似文献
998.
The effects of poly(vinyl alcohol) (PVA), poly(acrylic acid) (PAA), sodium polyacrylate (NaPA), poly(ethylene glycol) (PEG), pectin (P), and carboxymethyl cellulose (CMC) on the corrosion of cadmium in a 0.5M hydrochloric acid (HCl) solution were studied with both electrochemical impedance spectroscopy and Tafel plot techniques. Measurements were carried out at cathodic, open‐circuit, and anodic potentials. All the investigated polymers had inhibitory effects on both the cathodic (except for NaPA, P, and CMC) and anodic processes, with a predominant anodic inhibiting action. However, NaPA, P, and CMC exhibited a slight cathodic inhibiting action only at higher polymer concentrations. This behavior may be attributed to the very weak adsorbability of the polymers on the cathodic sites. Because PVA and PEG had hydroxy groups, there could be bridging between the polymer and the surface, resulting in an inhibiting effect in the HCl solution. However, PVA had much greater adsorbability on the surface than PEG at the anodic potential. The adsorption of most of the polymers obeyed a Temkin adsorption isotherm, and this indicated indicating that the main process of inhibition was adsorption. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 866–871, 2003 相似文献
999.
1000.