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1.
Yuanyuan Zhang Haiyan Lu Bing Wang Zhuo Zhang Xiaorong Lin Zhongzheng Chen Bin Li 《International Journal of Food Science & Technology》2015,50(6):1397-1404
Removal of imidacloprid and acetamiprid in tea infusions by microfiltration membrane using dead‐end model was investigated in the present study. The results showed that microfiltration significantly promoted the removal of both pesticides (P < 0.05) in tea infusions. Furthermore, the extent of removal was strongly influenced by the pore size of membrane, operational pressure and the concentrations of tea infusions. The initial concentration of imidacloprid and acetamiprid showed no significant effect on their removal rates. The maximum removal rates were 79.7% for imidacloprid and 81.9% acetamiprid. The changes in major chemical components of tea infusions after microfiltration were evaluated. The results indicated that microfiltration caused no considerable changes in total polyphenols and total free amino acids, and small but statistically significant losses (6.3–18.0%) of eight catechins and three methylxanthines when filtration volume reached to 200 mL. The present study validated the application of microfiltration as a potentially feasible and promising method for the removal of imidacloprid and acetamiprid residues from tea infusions. 相似文献
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The progress in atom transfer radical polymerization (ATRP) provides an effective means for the design and preparation of functional membranes. Polymeric membranes with different macromolecular architectures applied in fuel cells, including block and graft copolymers are conveniently prepared via ATRP. Moreover, ATRP has also been widely used to introduce functionality onto the membrane surface to enhance its use in specific applications, such as antifouling, stimuli-responsive, adsorption function and pervaporation. In this review, the recent design and synthesis of advanced functional membranes via the ATRP technique are discussed in detail and their especial advantages are highlighted by selected examples extract the principles for preparation or modification of membranes using the ATRP methodology. 相似文献
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从猫豆中提取左旋多巴的膜分离工艺探索 总被引:1,自引:0,他引:1
目的:使用新型膜分离技术从猫豆中提取左旋多巴并进行纯化和浓缩。方法:通过建立正交实验,对左旋多巴提取工艺进行研究,对实验结果进行分析优化,确定其提取的最佳条件参数;对猫豆浸提液进行分离纯化实验,系统研究了过程中的膜除杂和膜浓缩工艺,分别讨论了不同分离膜对左旋多巴提取液除杂、浓缩的效果,最终确定了三级膜处理过程。结果:使左旋多巴产品收率从传统工艺的50%提高至68.65%,同时,精制后产品纯度达到99.53%。结论:使用新型膜分离技术分离纯化左旋多巴是可行的,并且膜过程能耗低,污染少,不使用有毒试剂,实现了清洁生产。 相似文献
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The east and south-east of England has the lowest rainfall in the UK, water resources are limited and under pressure through increased demand and population growth. In the late 1990's AW Innovation (the AW R&D group) developed a process that could produce high purity water from sewage effluent using membrane technology. In late 1999 Texas Utilities (TXU) signed a contract with Alpheus Environmental for the supply of high purity water for Peterborough Power Station. The novel treatment plant was built in 1999 - 2000 and opened in July 2000 by the Mayor of Peterborough. This paper is a review of the plant design, the technology used for the treatment process and a summary of the first four years of operation.
Changing from potable water to high purity water produced from sewage effluent has brought significant benefits for the power station resulting in higher purity steam generation while reducing chemical, power and effluent discharge costs. In addition Anglian Water is now saving 1,000 m3 /day of potable water. 相似文献
Changing from potable water to high purity water produced from sewage effluent has brought significant benefits for the power station resulting in higher purity steam generation while reducing chemical, power and effluent discharge costs. In addition Anglian Water is now saving 1,000 m
8.
采用混凝-微滤工艺进行了地下水除氟的试验研究.静态试验表明了硫酸铝的混凝除氟效果比聚合硫酸铝的更佳.动态试验中发现,在改善饮用水水质及降低运行成本方面,采用CO2降低反应体系的pH比采用H2SO4更具有优越性.当原水F^-浓度为2.74 mg/L、硫酸铝投加量为154 mg/L、混凝反应器内CO2的溶入量为183.2 mg/L时,出水F^-浓度为0.98 mg/L、浊度<0.10 NTU、UV254为0.012 cm^-1、Al^3+<0.02 mg/L、SO4^2-浓度为125.77 mg/L、pH值为7.51,出水水质满足《生活饮用水卫生标准》(GB 5749-2006)的要求. 相似文献
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采用添加造孔剂高温烧结法制备了氧化镁-二氧化钛(MgO-TiO2)复合无机陶瓷微滤膜支撑体。分别研究了相同烧结制度下不同最高烧结温度、相同最高烧结温度不同的烧结制度下样品的孔隙率、抗弯强度及纯水通量的变化情况。采用热重分析(TG-DSC)、电子扫描电镜(SEM)和万能试验机等对样品进行热分析、观察样品形貌及抗弯强度等性能测试。研究表明,最高烧结温度和烧结制度对样品的性能有很大影响,采用最高烧结温度为1 400 ℃、升温速率分别为4、8、2 ℃/min的1400-482烧结制度所制备的支撑体的性能最佳,孔隙率为37.57%,抗弯强度为108.65 MPa,纯水通量为4 040 L/(m2?h?MPa)。 相似文献