英语翻译Although CS flat-sheet membranes or CS composite membranes (supported on other flat sheets or hollow fibers) have been prepared,[8][19-21] these membranes have appeared to be relatively less attractive because of their small specific surf
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英语翻译Although CS flat-sheet membranes or CS composite membranes (supported on other flat sheets or hollow fibers) have been prepared,[8][19-21] these membranes have appeared to be relatively less attractive because of their small specific surf
英语翻译
Although CS flat-sheet membranes or CS composite membranes (supported on other flat sheets or hollow fibers) have been prepared,[8][19-21] these membranes have appeared to be relatively less attractive because of their small specific surface areas or the small amount of CS contained and,hence,low adsorption capacity for adsorptive separation.[8] To increase the specific surface area,hollow-fiber membranes are usually the preferred membrane configuration (because of the high packing density).[21] Unfortunately,CS has encountered significant difficulty in the preparation of hollow-fiber membranes with adequate mechanical strength so far.CS solutions have very high viscosities,and the polymer dope solutions used to spin the hollow-fiber membranes usually unavoidably have a low CS concentration (often 5 wt %).There have been three representative reports in the literature about the preparation of CS hollow-fiber membranes.[22-24] The authors of the first two studies[22][23] prepared CS dope solutions with about 3-5 wt % concentrations,and the spun hollow-fiber membranes did not seem to have good self-supporting capability in wet state.The third study reported[24] CS dope solutions with concentrations up to 7 wt % by using Low-viscosity CS,and the strength of the spun hollow-fiber membranes was increased by increasing the crystallinity of CS in the spinning process.Not only does the requirement for low-viscous CS limit the choice of CS products in the market,a higher crystallinity also reduces the adsorption capacity of CS and is,therefore,not desirable for adsorptive CS membranes.
The major obstacle in preparing CS hollow-fiber membranes with a high mechanical strength arises,to a large extent,from the practical difficulty of obtaining highly concentrated homogeneous CS dope solutions to spin the hollow-fiber membranes.In this study,a novel method was developed to prepare homogeneous and high-concentration CS dope solutions (up to 18 wt %).CS hollow-fiber membranes fabricated from these high concentration CS solutions showed good mechanical strengths.Adsorption studies for copper-ion removal with the prepared CS fibers showed very high adsorption capacities (copper ions were used in this study as a model heavy metal for easy comparison with some early results reported in the literature).
英语翻译Although CS flat-sheet membranes or CS composite membranes (supported on other flat sheets or hollow fibers) have been prepared,[8][19-21] these membranes have appeared to be relatively less attractive because of their small specific surf
尽管c flat-sheet膜或CS复合膜(支持其他平片或中空纤维膜)已经准备好了,[8][19-21]这些膜相对较少出现了具有吸引力,因为他们的小特殊表面区域或少量的密室中较低,因此,吸附容量为吸附分离.[8]增加了中空纤维超滤膜的比表面积,通常是首选的膜结构(因为封装密度高.)[m].北京:21]不幸遇到很大的难度,c在准备中空纤维超滤膜的机械强度和适当为止.CS方案有很高的粘度、聚合物涂料方案用于旋转中空纤维超滤膜通常都很低浓度难免CS(通常5股份).有三种代表性的文献报道关于制备的中空纤维超滤膜22-24.[c],作者在前两项研究(22)[m].北京:23]预备方案与有关3-5 CS涂料股份的浓度,与纺中空纤维超滤膜似乎没有好的自立能力在湿的状态.第三项研究报告(24)CS涂料方案与浓度达到7股份利用低粘度、和强度中空纤维超滤膜纺提高结晶度的密室中增加了纺纱工艺流程.它不仅要求的选择low-viscous CS限制CS产品在市场、更高的结晶度也降低了吸附容量大,因此,c、不合宜的吸附CS膜.
主要的障碍和中空纤维超滤膜的制备CS机械强度高,在很大程度上,从实际困难,均取得高度集中的解决方案来旋转CS涂料中空纤维超滤膜.在这项研究中,提出了一种新颖的方法来准备均匀、高浓度溶液(CS涂料股份).中空纤维超滤膜从CS CS解决这些高浓度显示出良好的机械力量.为copper-ion吸附研究,准备CS纤维显得非常高的吸附能力(铜离子被应用于该研究作为模型比较容易重金属的一些早期的文献报告).
虽然政务司司长平片膜或CS复合膜(片或其他单位中空纤维)的支持,已经拟定,[8] [19-21]这些膜具有似乎相对较少,因为他们比表面积小的或有吸引力CS的少量含有,因此,为吸附分离吸附能力低。[8]增加比表面积,中空纤维膜通常是首选的配置,(因为膜包装的高密度)。[21]不幸的是,CS,就遇到了重大足够的机械强度的中空纤维膜制备困难至今。政务解决方案具有很高的粘度,聚合物涂料解决方案中使用旋转的...
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虽然政务司司长平片膜或CS复合膜(片或其他单位中空纤维)的支持,已经拟定,[8] [19-21]这些膜具有似乎相对较少,因为他们比表面积小的或有吸引力CS的少量含有,因此,为吸附分离吸附能力低。[8]增加比表面积,中空纤维膜通常是首选的配置,(因为膜包装的高密度)。[21]不幸的是,CS,就遇到了重大足够的机械强度的中空纤维膜制备困难至今。政务解决方案具有很高的粘度,聚合物涂料解决方案中使用旋转的中空纤维膜通常难免有低浓度政务(通常为5 wt%)。有三个关于CS的中空纤维膜制备文学代表的报告。[22-24]前两项研究的作者[重量约3-5%浓度22] [23]准备政务涂料解决方案,和纺中空纤维膜似乎并不具备良好的自我配套能力在湿状态。第三项研究报告[24浓度]政务涂料的解决方案,7 wt%时使用低粘度政务,以及纺中空纤维膜的强度增加了纺纱工艺的CS的结晶度增加。低黏CS的要求不仅限制CS产品选择在市场上,更高的结晶性也减少CS吸附容量并且为吸附CS膜不是,因此,中意的。 \
在编写具有高机械强度政务中空纤维膜的主要障碍时,在很大的程度上,从高度集中的单一获取政务涂料解决方案,以旋转的中空纤维膜的实际困难。在这项研究中,开发了一种新的方法编制均匀和高浓度掺杂政务解决方案(质量分数可达18%)。政务中空纤维膜制备从这些高浓度政务解决方案,具有良好的机械强度。铜离子与编制政务纤维吸附去除研究显示了非常高的吸附能力(铜离子,在本模型与一些早期结果比较容易重金属研究中使用的文献报道)。
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