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充填系统中必须设计一料仓来存储充填用尾砂,因此,有必要建立砂浆实验室以研究充填技术和料仓设计准则。本文介绍了砂浆充填系统的设计原理和优化砂浆系统的测试方法的重要性,实验得出评价方法适用于研究多种砂材料,可根据模型试验数据的不同比例设计料仓,料仓模拟试验已成功用料仓的设计和实际应用,因而成为充填设计的有效方法。 相似文献
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在科技飞速发展的今天,人们对电力的需求越来越大,电力系统稳定性也越来越受到人们的关注,本文对电力系统稳定控制方式从三个方面进行深入分析和研究,旨在为提高电力系统稳定性提供参考。 相似文献
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The long-term destabilization process of a water-in-oil emulsion was investigated with two different biodemulsifiers produced under different culture conditions by Alcaligenes sp. S-XJ-1. Biodemulsifier I was obtained by using paraffin as substrate at initial culture pH of 10 and biodemulsifier II was produced with waste frying oils at pH of 7. The former exhibited higher demulsifying ability and interfacial activity than the latter. Bottle test, microscopy and Turbiscan Lab(?) Expert were used to investigate the biological demulsification process. It was found that biodemulsifiers' ability to decrease the interfacial tension played a more important role in demulsification than their ability to decrease the surface tension. Owing to their amphiphilic nature, demulsification process began with the adsorption of the biodemulsifiers onto the water-oil interface. Then the biodemulsifiers reacted with the emulsifiers because of their interfacial activity. As a result, thin liquid film was removed from the surface of dispersed droplets and coalescence occurred. This led to the settling of the dispersed droplets and the clarification of the continuous phase. Turbiscan Lab(?) Expert can be used to evaluate the demulsification efficiency and to analyze the destabilization process of different biodemulsifiers. It is a rapid and accurate method to screen high-efficiency demulsifiers from other bioproducts. 相似文献
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Svecova L Dossot M Cremel S Simonnot MO Sardin M Humbert B Den Auwer C Michot LJ 《Journal of hazardous materials》2011,189(3):764-772
Selenium is a known toxic element released in the environment by anthropogenic activities. The present study is devoted to the aqueous sorption behaviour of selenium oxyanions (selenate and selenite) on a reference oxide surface, namely rutile TiO(2). Batch sorption kinetics and isotherms have been studied using different physico-chemical conditions of the solution (changes of pH and ionic strength). The sorption was favoured for both anions in acidic conditions, in agreement with a surface complexation mechanism and CD-MUSIC predictions. Spectroscopic investigations of the sorbed rutile powder were also consistent with such a mechanism. EXAFS spectra confirmed that for selenite anions, an inner-sphere mechanism was the most probable process observed. Dynamic sorption experiments using a column filled with rutile powder also substantiated that a part of the surface complexes follows the inner-sphere mechanism, but also evidenced that an outer-sphere mechanism cannot be excluded, especially for selenate anions. 相似文献
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