膜分离法回收合成氨弛放气中氢气

介绍了膜分离的原理和应用。实践表明该方法具有效率高、流程简单、操作灵活容易、纯度高和收率高等优点。     

膜-粉末炭反应器净化微污染源水

采用膜-粉末炭反应器处理微污染源水的试验结果表明,该工艺对水中的有机物具有较好的净化效果,在水温《10℃的条件下,处理可生化性很低的三家店水库水时对CODMn的去除率仍保持在65%左右;工艺对CODMn、UV254、UV410的去除效果依次增强.     

利用SiO2包膜技术提高群青蓝颜料耐酸性的研究

采用廉价的SiO2 对群青颜料进行致密包膜 ,使群青颜料耐酸性能得到提高 ,解决了群青在聚氯乙烯型材使用中产生的变色现象 ,拓宽了应用范围     

Transport of chromium(VI) through a Cyanex 921‐supported liquid membrane from HCl solutions

The transport of chromium(VI) through a flat‐sheet supported liquid membrane containing Cyanex 921 as a carrier has been investigated. The permeation of the metal is investigated as a function of various experimental variables: hydrodynamic conditions, concentration of chromium(VI) and HCl in the feed phase, carrier concentration and diluent in the membrane and strippant concentration in the stripping phase. The mass transfer coefficient and the thickness of the aqueous boundary layer were calculated from the experimental data. Furthermore, the selectivity of Cyanex 921‐based flat‐sheet supported liquid membrane towards different metal ions and the behaviour of the system against other carriers are presented. Copyright © 2003 Society of Chemical Industry     

乙基叔丁基醚/β分子筛膜反应精馏

研究了混合碳四和乙醇合成乙基叔丁基醚(ETBE)的反应精馏过程。实验以支撑β分子筛膜为催化精馏元件，异丁烯转化率高达95％，回流比和醇烯摩尔比是影响异丁烯转化率的主要因素。与甲基叔丁基醚(MTBE)的反应精馏过程相比，以乙醇取代甲醇，只需对MTBE生产的操作条件作一些简单的调整，就可在其生产装置上合成ETBE。     

Membrane Packaging System to Permit Safe Hydration of Freeze-Dried Contents with Impure Water

We tested the feasibility of using polymer membranes for a self-hydrating packaging system to reconstitute freeze-dried foods using nonpurified water. Several commercial membranes were screened according to (1) hydration rate, (2) water permeability, (3) passage of microorganisms, (4) salt rejection, and (5) strength. The most promising membranes were used for developing and testing prototype packaging systems. A feasible self-contained rehydration system was a nylon-6 polyamide membrane that rehydrated the freeze-dried food within 30 min while passage of microorganisms was prevented. The temperature was 37°C, and the food contained 0.5g/5g of a low molecular weight solute (salt). Such self-contained membrane rehydration systems must be designed to accommodate expected environmental conditions such as temperature, relative humidity, and nature of the product.     

Crossflow microfiltration of gum arabic solutions: Comparison of the classical system with the co-current permeate flow system

Gum arabic is a natural gum exuded mainly by the trees Acacia senegal , currently used in the food industries for its emulsifying, thickening and stabilizing properties. Its present processing includes various operations providing a quite turbid product. Crossflow microfiltration could be interesting for the clarification and the cold-pasteurization of the gum arabic solutions. Several experiments were therefore made with the crossflow microfiltration unit at ENSIA, using two different systems: the classical one (without permeate circulation), and the co-current permeate flow system (CCPF) allowing the exploration of the low transmembrane pressures range. With gum arabic solutions of 0.17g solids g⁻¹ solution and 70°C, the best results after 60 min of filtration (105.7 L h⁻¹ m⁻², 4.4% of solids retention and 83.4% of clarification) were obtained with the CCPF system at low transmembrane pressure and high crossflow velocity (0.3 bar and 7.5ms⁻¹).     

核孔膜生产线膜微孔制备工艺实验研究

本文介绍核孔膜生产线,重点描述了膜微孔制备工艺的实验研究。对于PC和PES膜,已得到32种工况下的扩孔公式,其形式为D=A+Bt,其中D——孔径,t——扩孔时间,A,B为特定工艺参数下的常数值.通过实验。得到了膜孔密度N与300~#核反应堆功率P、热柱辐照位置L的经验公式,即N=6.97×10~5×10~3×101~(1.18L).在本生产线上可生产最大幅面为3 140mm×240mm,孔径为0.04～10 μm的多系列多规格的核孔膜产品。     

Effect of antioxidant contained in poly(ethylene glycol) on cell fusion

The effect of antioxidants contained in poly(ethylene glycol) (PEG) on cell fusion was studied using L929 cells in the monolayer state. Hydroquinone monomethyl ether (HQME), 2-mercaptobenzimidazole (MB), butyl hydroxyanisole (BHA) and 2,6-di-(t-butyl)-4-methylphenol (BHT) were chosen from the antioxidants that have currently been used to protect commercially available PEG from oxidation. Cell culture was conducted in 40% w/w aqueous solution of PEG with a molecular weight of 3000 in the presence of different concentrations of antioxidants. BHA clearly enhanced membrane fusion of L929 cells with increasing concentration in PEG solution, whereas HQME, MB and BHT had no significant effect on cell fusion. The enhancement of cell fusion by BHA might be ascribed to balanced hydrophobicity and high water solubility in comparison with the other three antioxidants.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.