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241.
水力旋流器能耗机制与节能原理研究:Ⅵ.低能耗旋流器压力场结构及能耗 … 总被引:4,自引:4,他引:0
对低能耗水力旋流器内的湍动压力场的时结构与脉动结构进行了系统研究。 相似文献
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近年来,膜分离过程中的十字流微滤机理研究在国外非常活跃,在预测过滤速率,动态滤饼的形成,提出了一些新观点和新的机理,加深了对十字流过滤通量下降和膜污染的认识和理解。本文介绍了这些理论和实验研究的成果。 相似文献
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水力旋流器结构与分离性能研究(六):柱段结构(长度) 总被引:4,自引:0,他引:4
研究了水力旋流器主段长度对其分离性能的影响,结果表明,随着柱段长度的增大,水力旋流器处理能力呈单调上升趋势,其分离修正总效率呈上升趋势,其溢流浓度则呈单调减小趋势,在水力旋流器用于固液分离场合时,其柱段长度宜较长为佳。 相似文献
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聚(N-异丙基丙烯酰胺)温敏微球的粒径及单分散性 总被引:3,自引:2,他引:3
Thermo-responsive poly (N-isopropylacrylamide-co-styrene ) [P(NIPAM-co-St)] hydrogel microspheres were prepared by surfactant-free emulsion polymerization. The effects of initiator dosage, stirring rate, phase ratio and polymerization time on particle size and monodispersity were investigated. The results showed that, with increasing initiator dosage, mean diameter increased slightly to a maximum, and then decreased drastically; meanwhile, the monodispersity of the particles became a little better at first, and then became worse significantly. With increasing stirring rate, particle diameter decreased while the monodispersity became worse. When the amount of phase rate increased, the mean diameter became larger simply, whereas the monodispersity became worse firstly and then became better again. As the polymerization proceeded, the mean diameter of the particles hardly changed, and the monodispersity became better gradually. The microspheres prepared under the optimum experimental conditions showed satisfactory particle size and monodispersity. 相似文献
250.
Effect of Graft Yield on the Thermo-Responsive Permeability Through Porous Membranes with Plasma-Grafted Poly(N-isopropylacrylamide)Gates 下载免费PDF全文
The effect of graft yield on both the thermo-responsive hydraulic permeability and the thermo-responsive diffusional permeability through porous membranes with plasma-grafted poly(AT-isopropylacrylamide) (PNIPAM) gates was investigated. Both thermo-responsive flat membranes and core-shell microcapsule membranes with a wide range of graft yield of PNIPAM were prepared using a plasma-graft pore-filling polymerization method. The grafted PNIPAM was formed homogeneously throughout the entire thickness of both the flat polyethylene membranes and the microcapsule polyamide membranes. Both the hydraulic permeability and the diffusional permeability were heavily dependent on the PNIPAM graft yield. With increasing the graft yield, the hydraulic permeability (water flux) decreases rapidly at 25℃ because of the decrease of the pore size; however, the water flux at 40℃ increases firstly to a peak because of the increase of hydrophobicity of the pore surface, and then decreases and finally tends to zero because o 相似文献