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十二烷基硫酸钠对膜蒸馏过程影响 预览
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作者 袁子怡 樊华 +2 位作者 侯得印 王凯 王军 《化工学报》 EI CAS CSCD 北大核心 2019年第4期1455-1463,共9页
膜蒸馏具有较低的操作压力、操作温度以及运行成本等优点,因此在水处理方面有广泛的应用前景。但是膜蒸馏过程中的膜润湿和膜污染现象仍然是阻碍其工业化应用的主要问题。表面活性剂作为一种能显著降低溶液表面张力、改变进料液性质的物... 膜蒸馏具有较低的操作压力、操作温度以及运行成本等优点,因此在水处理方面有广泛的应用前景。但是膜蒸馏过程中的膜润湿和膜污染现象仍然是阻碍其工业化应用的主要问题。表面活性剂作为一种能显著降低溶液表面张力、改变进料液性质的物质,对膜蒸馏造成的影响值得被研究。基于此,研究了在直接接触式膜蒸馏(DCMD)过程中表面活性剂对不同商业微孔疏水膜造成的影响,选用了一种常见的阴离子表面活性剂十二烷基硫酸钠(SDS)进行实验。结果表明,进料液中SDS浓度的上升会引起更为严重的膜润湿现象,并且所使用的三种商业膜中,双疏膜抗润湿性最强,而PVDF膜最弱。而当Ca2+大量存在于进料液中时,Ca2+与SDS的聚集降低了膜润湿的程度但其在膜表面的沉积造成了严重的膜污染。界面相互作用自由能的计算结果表明Ca2+/SDS与PVDF膜之间的吸引力最大、PTFE膜其次、双疏膜最小,这一结果与膜蒸馏过程中通量变化情况相符。 展开更多
关键词 蒸馏 表面活性剂 膜润湿 膜污染
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Copper-exchanged LTA zeolite membranes with enhanced water flux for ethanol dehydration
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作者 Can Xu Chen Zhou +1 位作者 Sui Wang Aisheng Huang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第6期1204-1206,共3页
LTA (Linde Type A) molecular sieve has widely used in adsorption and separation due to its regular pore structure, high thermal stability and chemical stability. Copper-exchanged LTA (Cu-LTA) zeolite membranes with en... LTA (Linde Type A) molecular sieve has widely used in adsorption and separation due to its regular pore structure, high thermal stability and chemical stability. Copper-exchanged LTA (Cu-LTA) zeolite membranes with enhanced water flux of ethanol dehydration were developed through copper ion exchange of Na-LTA zeolite membrane. In the first step, a thin and well intergrown Na-LTA zeolite membrane was prepared on macroporousα-Al2O3 tube which was modified by 3-aminopropyltriethox-ysilane (APTES). Afterwards, copper exchange of the as-synthesized Na-LTA zeolite membranes was done to prepare Cu-LTA zeolite membrane. According to characterizations of XRD, FESEM, and XPS, both the morphology and structure of the Cu-LTA zeolite membranes are identical to those of the Na-LTA zeolite membranes, and there are no cracks and pinholes are found in the membrane layer. Attributing to a wider pore diameter because two sodium ions of Na-LTA framework are replaced by one copper ion, the Cu-LTA zeolite membrane displays a higher water flux in the separation of ethanol/water mixture than Na-LTA membranes. At 75 °C, the water flux of the Cu-LTA zeolite membrane is 3.52 kg m^-2 h^-1 with water/ethanol separation factor of 3591, while the water flux of the Na-LTA zeolite membrane is only 1.65 kg m^-2 h^-1 with water/ethanol separation factor of 4082. 展开更多
关键词 Molecular SIEVE MEMBRANE LTA ZEOLITE MEMBRANE Ion EXCHANGE Cu-LTA ZEOLITE MEMBRANE PERVAPORATION
Aggravation of membrane fouling and methane leakage by a three-phase separator in an external anaerobic ceramic membrane bioreactor
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作者 Chao Pang Chunhua He +2 位作者 Zhenhu Hu Shoujun Yuan Wei Wang 《环境科学与工程前沿(英文)》 SCIE EI CAS CSCD 2019年第4期35-43,共9页
The three-phase separator is a critical component of high-rate anaerobic bioreactors due to its significant contribution in separation of biomass, wastewater, and biogas. However, its role in an anaerobic membrane bio... The three-phase separator is a critical component of high-rate anaerobic bioreactors due to its significant contribution in separation of biomass, wastewater, and biogas. However, its role in an anaerobic membrane bioreactor is still not clear. In this study, the distinction between an external anaerobic ceramic membrane bioreactor (EAnCMBR) unequipped (R1) and equipped (R2) with a three-phase separator was investigated in terms of treatment performance, membrane fouling, extracellular polymers of sludge, and microbial community structure. The results indicate that the COD removal efficiencies of Rl and R2 were 98.2%±0.4% and 98.1%±0.4%, respectively, but the start-up period of R2 was slightly delayed. Moreover, the membrane fouling rate of R2 (0.4 kPa/d) was higher than that of Rl (0.2 kPa/d). Interestingly, the methane leakage from R2 (0.1 L/d) was 20 times higher than that from Rl (0.005 L/d). The results demonstrate that the three-phase separator aggravated the membrane fouling rate and methane leakage in the EAnCMBR. Therefore, this study provides a novel perspective on the effects of a three-phase separator in an EAnCMBR. 展开更多
关键词 ANAEROBIC MEMBRANE BIOREACTOR Three-phase separator MEMBRANE fouling METHANE LEAKAGE Sludge property
纳滤膜在功能性低聚糖分离纯化中的应用研究进展 预览 被引量:1
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作者 陈献富 季华 范益群 《化工进展》 EI CAS CSCD 北大核心 2019年第1期394-403,共10页
功能性低聚糖具有抗肿瘤、抗放射、抗凝血、消炎和调节免疫力等医疗保健作用,广泛应用于食品科学和生物医药等领域。纳滤作为一种高效的膜分离技术,在功能性低聚糖的分离与纯化中的应用得到越来越多的关注。本文分析了纳滤膜对功能性低... 功能性低聚糖具有抗肿瘤、抗放射、抗凝血、消炎和调节免疫力等医疗保健作用,广泛应用于食品科学和生物医药等领域。纳滤作为一种高效的膜分离技术,在功能性低聚糖的分离与纯化中的应用得到越来越多的关注。本文分析了纳滤膜对功能性低聚糖的分离机理,综述了纳滤膜在功能性多糖分离纯化中的应用进展,讨论了纳滤分离过程的影响因素,主要包括功能性多糖料液的性质、膜过程的操作参数以及膜材料本身的性质等。其中,料液的性质主要体现在组成、浓度、黏度等方面;操作参数主要体现在压力、温度、膜面流速和pH等方面;而膜材料的性质主要体现在微结构和表面性质两个方面。最后,进一步指出纳滤膜技术用于功能性多糖分离纯化时在设备成本、膜材料及膜污染等方面存在的问题,并对未来纳滤膜技术在低成本专用膜材料及系统开发和膜污染控制方面的研究进行了展望。 展开更多
关键词 纳滤 低聚糖 纯化 膜污染
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Management of an Adult with Goodpasture’s Syndrome Following Brain Trauma with Extracorporeal Membrane Oxygenation:A Case Report 预览
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作者 Shan Wang Haiyan Yin +4 位作者 Youfeng Zhu Pei Tao Rui Zhang Yonghui Ma Jianrui Wei 《中国医学科学杂志:英文版》 CAS CSCD 2019年第3期226-229,共4页
A 22-year-old man suffered from acute pulmonary hemorrhage and deteriorated renal function occurred within 3 days after traumatic brain injury.Mechanical ventilation cannot correct his severe hypoxemia,therefore,venoa... A 22-year-old man suffered from acute pulmonary hemorrhage and deteriorated renal function occurred within 3 days after traumatic brain injury.Mechanical ventilation cannot correct his severe hypoxemia,therefore,venoarterial extracorporeal membrane oxygenation(VA-ECMO)support was initiated and finally resolved his hypoxemia.Concomitantly,continuous renal replacement therapy was performed to improve his kidney function.Although no anti-glomerular basement membrane(anti-GBM)antibody was detected in serum,Goodpasture’s syndrome was considered.After treated with methylprednisolone pulse therapy and plasmapheresis,his renal function was significantly improved.ECMO was eventually discontinued after 60 hours of treatment and extubated on day 10.He was discharged home with normal pulmonary and renal functions. 展开更多
关键词 extracorporeal membrane oxygenation pulmonary hemorrhage Goodpasture's Syndrome anti-glomerular basement membrane antibody
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厌氧膜反应器处理制药厂废水实验 预览
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作者 黄贞岚 付嘉琦 +1 位作者 麦兆环 吴九九 《江西科学》 2019年第4期497-500,共4页
制药厂高浓度有机废水采用自主设计的膜-厌氧反应器进行厌氧消化和膜过滤实验,观察制药废水COD去除效果和COD容积负荷,实验结果表明,膜-厌氧反应运行稳定,产气量高,出水水质较好,COD去除率最高达99.4%,COD容积负荷最高达到25kg/m3·... 制药厂高浓度有机废水采用自主设计的膜-厌氧反应器进行厌氧消化和膜过滤实验,观察制药废水COD去除效果和COD容积负荷,实验结果表明,膜-厌氧反应运行稳定,产气量高,出水水质较好,COD去除率最高达99.4%,COD容积负荷最高达到25kg/m3·d,底部污泥浓度达到30.1g/L,采用此工艺可以取消添加絮凝剂预处理工序,降低了运行成本。 展开更多
关键词 制药厂废水 膜污染 厌氧反应处理
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Effects of protein properties on ultrafiltration membrane fouling performance in water treatment
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作者 Yanyan Ding Baiwen Ma +1 位作者 Huijuan Liu Jiuhui Qu 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期273-281,共9页
Protein-like substances always induce severe ultrafiltration(UF) membrane fouling. To systematically understand the effect of proteins, regenerated cellulose UF membrane(commonly used for protein separation) performan... Protein-like substances always induce severe ultrafiltration(UF) membrane fouling. To systematically understand the effect of proteins, regenerated cellulose UF membrane(commonly used for protein separation) performance was investigated in the presence of bovine serum albumin(BSA) under various water conditions. Results showed that although trypsin enhanced the membrane flux via proteolysis, catalysis took a long time. Membrane fouling was alleviated at high solution p H and low water temperature owing to the strong electrostatic repulsion force among BSA molecules. Both Na+ and Ca2+could increase membrane flux. However, Ca2+played a bridging role between adjacent BSA molecules,whereas membrane fouling was alleviated via a hydration repulsion force with Na+. The order of influence on membrane fouling was as follows: Ca2+concentration > Na+concentration > pH > temperature > trypsin concentration. Furthermore, a polyvinylidene fluoride UF membrane experiment showed that Ca2+could reduce the fouling induced by BSA. Thus, the differences in UF membrane performance will have application potential for alleviating UF membrane fouling induced by proteins during water treatment. 展开更多
关键词 ULTRAFILTRATION MEMBRANE Protein PROPERTIES Influencing FACTORS MEMBRANE PERFORMANCE
膜前预处理技术在印染废水处理中的应用进展 预览
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作者 丁凌峰 《广东化工》 CAS 2019年第9期189-191,共3页
膜分离技术在印染废水处理领域应用广泛,实际应用中,膜污染难以避免。本文介绍了膜分离及集成技术在印染水处理中的应用,分析了膜污染存在的原因及解决膜污染问题的研究现状,综述了多级过滤、化学絮凝、电絮凝等前处理技术,预处理可延... 膜分离技术在印染废水处理领域应用广泛,实际应用中,膜污染难以避免。本文介绍了膜分离及集成技术在印染水处理中的应用,分析了膜污染存在的原因及解决膜污染问题的研究现状,综述了多级过滤、化学絮凝、电絮凝等前处理技术,预处理可延缓膜污染,延长膜寿命,降低运行成本,是膜分离技术在印染废水应用的关键环节,并对膜前预处理技术应用前景进行了展望。 展开更多
关键词 印染废水 膜集成系统 絮凝
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Application of a hybrid gravity-driven membrane filtration and dissolved ozone flotation(MDOF)process for wastewater reclamation and membrane fouling mitigation
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作者 Xin Jin Wei Wang +5 位作者 Shuai Wang Pengkang Jin Xiaochang C.Wang Wushou Zhang Weijun An Yong Wang 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第7期17-27,共11页
This study proposed a novel membrane filtration and dissolved ozone flotation integrated(MDOF) process and tested it at pilot scale. Membrane filtration in the MDOF process was operated in gravity-driven mode, and req... This study proposed a novel membrane filtration and dissolved ozone flotation integrated(MDOF) process and tested it at pilot scale. Membrane filtration in the MDOF process was operated in gravity-driven mode, and required no backwashing, flushing, or chemical cleaning. Because ozone was added in the MDOF process, ozonation, coagulation, and membrane filtration could occur in a single reactor. Moreover, in situ ozonation occurred in the MDOF process, which differs from the conventional pre-ozonation membrane filtration process. Significant enhancement of turbidity removal was further achieved through the addition of membrane filtration. Membrane fouling was mitigated in the MDOF process compared to the MDAF process. In situ ozonation in the MDOF process decreased the fluorescence intensity and transformed the high MW dissolved organics into small MW compounds. For the fouling layer, the extracellular polymeric substance(EPS) contents and cake layer morphology were analyzed. The results indicated that the contents of EPS decreased. Furthermore, a thinner and more loosely structured cake layer formed in the MDOF process. Because coagulation and ozonation occurred simultaneously in a single reactor, the generation of hydroxyl radicals was enhanced through the catalytic effect of Al-based coagulants on ozone decomposition, which further alleviated membrane fouling in the MDOF process. 展开更多
关键词 Dissolved OZONE FLOTATION Gravity-driven MEMBRANE filtration MEMBRANE fouling In situ ozonation
Influence of pore size and membrane surface properties on arsenic removal by nanofiltration membranes
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作者 Nathalie Tanne Rui Xu +3 位作者 Mingyue Zhou Pan Zhang Xiaomao Wang Xianghua Wen 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第2期55-62,共8页
Nanofiltration(NF)has a great potential in removing arsenate from contaminated water.The performance including arsenate rejection,water permeability and resistance to fouling could however differ substantially among N... Nanofiltration(NF)has a great potential in removing arsenate from contaminated water.The performance including arsenate rejection,water permeability and resistance to fouling could however differ substantially among NF membranes.This study was conducted to investigate the influence of membrane pore size and surface properties on these aspects of membrane performance.Four fullyaromatic NF membranes with different physicochemical properties were adopted for this study.The results showed that surface charge,hydrophobicity,roughness and pore size could affect water permeability and/or arsenate rejection considerably.A more negative surface charge was desirable to enhance arsenate rejection rates.NF90 and a non-commercialized membrane(M#1)demonstrated the best performance in terms of arsenate rejection and water permeability.The M#1 membrane showed less membrane fouling than NF90 when used for filtration of real arsenic-containing groundwater.This was mainly due to its distinct chemical composition and surface properties.A severe membrane fouling could lead to a substantial reduction of arsenic rejection.The M#1 membrane showed the best performance,which indicated that membrane modification could indeed enhance the overall membrane performance for water treatment. 展开更多
关键词 ARSENATE NANOFILTRATION DRINKING water MEMBRANE PROPERTY MEMBRANE FOULING
第十二届亚太膜学会(AMS)概述 预览
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作者 任丹 汪林 +1 位作者 吴欢欢 王晓琳 《膜科学与技术》 CAS CSCD 北大核心 2019年第4期142-147,共6页
本文介绍了第十二届亚太膜学术会议的内容,分别介绍了“水和水处理”、“脱盐”、“溶剂分离与脱水”、“气体分离”、“新膜材料”等十一个会议主题的研究进展.
关键词 膜会议
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高性能锂离子二次电池隔膜
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作者 王惠亚 赵立敏 +1 位作者 张芳 何丹农 《化学进展》 SCIE CAS CSCD 北大核心 2019年第9期1251-1262,共12页
随着电动汽车对锂离子电池功率要求的不断提高,高性能锂离子电池逐渐成为了人们研究的热点。隔膜作为锂离子电池的关键部件之一,发挥着隔离正负极材料以及为锂离子迁移提供通道的作用。此外,隔膜的热稳定性也直接影响着锂离子电池的安... 随着电动汽车对锂离子电池功率要求的不断提高,高性能锂离子电池逐渐成为了人们研究的热点。隔膜作为锂离子电池的关键部件之一,发挥着隔离正负极材料以及为锂离子迁移提供通道的作用。此外,隔膜的热稳定性也直接影响着锂离子电池的安全性能。聚烯烃微孔隔膜由于其出色的化学稳定性、机械强度以及价格低廉而被广泛应用于锂离子电池中。然而,其热稳定性差以及不易湿润等缺点给高性能锂离子电池的广泛应用带来很大隐患。因此,本文探讨了聚烯烃微孔隔膜的表面改性,以此为出发点,介绍了基于聚合物表面改性的聚烯烃微孔隔膜、基于无机纳米颗粒的聚烯烃微孔隔膜、基于有机-无机复合材料的聚烯烃微孔隔膜的研究进展。在基于无机纳米颗粒的聚烯烃微孔隔膜的介绍中,本文还对原子层沉积法、化学气相沉积法、物理气相沉积法等先进表面改性方法进行了简单介绍。随后,从湿法制备、相转化法、呼吸图法、静电纺丝法以及原位聚合法5种方法出发,对其他聚合物微孔隔膜的研究进展进行了介绍。最后,本文对将来高性能隔膜材料的研究方向上作出展望,旨在为高性能锂离子二次电池隔膜材料的研究和应用提供参考。 展开更多
关键词 锂离子二次电池 隔膜材料 表面改性 聚烯烃隔膜 原位聚合
High performance octahedral PtNi/C catalysts investigated from rotating disk electrode to membrane electrode assembly
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作者 Bing Li Jue Wang +5 位作者 Xin Gao Congwei Qin Daijun Yang Hong Lv Qiangfeng Xiao Cunman Zhang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第2期281-287,共7页
Octahedral PtNi/C catalysts have demonstrated superior catalytic performance in oxyge n reduction reacti on (ORR) over commercial Pt/C with rotating disk electrode (RDE). However, it is not trivial to translate such p... Octahedral PtNi/C catalysts have demonstrated superior catalytic performance in oxyge n reduction reacti on (ORR) over commercial Pt/C with rotating disk electrode (RDE). However, it is not trivial to translate such promising results to real-world membrane-electrode assembly (MEA). In this work, we have synthesized octahedral PtNi/C catalysts using poly(diallyldimethylammonium chloride)(PDDA) as a capping age nt and in vestigated their performance from RDE to MEA. In RDE, mass activity and specific activity of the optimized octahedral PtNi/C catalyst for oxygen reduction reaction (ORR) are nearly 19 and 28 times high of the state-of-the-art commercial Pt/C, respectively. At MEA level, the octahedral PtNi/C catalyst exhibits excelle nt power generation performa nee and durability paired with commercial Pt/C ano de. Its cell voltage at 1,000mA·cm^-2 reaches 0.712 V, and maximum power density is 881.6 mW·cm^-2 and its performance attenuation is also less, around 11.8% and 7% under galvanostatic condition of 1,000 mA·cm^-2 for 100 h. Such results are investiaged by thermodynamic analysis and fundametal performance modeling, which indicate the single cell performance can be further improved by reducing the size of PtNi/C catalyst agglomerates. Such encouraging results have demonstrated the feasibility to convey the superior performance of octahedral PtNi/C from RDE to MEA. 展开更多
关键词 PROTON exchange MEMBRANE fuel cell (PEMFC) OCTAHEDRAL PtNi/C oxygen reduction reaction (ORR) durability MEMBRANE ELECTRODE assembly (MEA)
Glutathione-capped quantum dots for plasma membrane labeling and membrane potential imaging
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作者 Guangcun Chen Yejun Zhang +3 位作者 Zhao Peng Dehua Huang Chunyan Li Qiangbin Wang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第6期1321-1326,共6页
The plasma membrane of cells is a crucial biological membrane that involved in a variety of cellular processes including cell signaling transduction through membrane electrical activity.Recently,monitoring membrane el... The plasma membrane of cells is a crucial biological membrane that involved in a variety of cellular processes including cell signaling transduction through membrane electrical activity.Recently,monitoring membrane electrical activity using fluorescence imaging has attracted numerous attentions for its potential applications in evaluating how the nervous system works.However,the development of ideal fluorescent voltage-sensitive probes with both high membrane labeling efficiency and voltage sensitivity is still retain a big challenge.Herein,glutathionecapped CdSe@ZnS quantum dots (CdSe@ZnS-GSH QDs) with a size of 2.5 nm and an emission peak at 520 nm are synthesized using a facile ligand exchange method for plasma membrane labeling and membrane potential imaging.The as-synthesized CdSe@ZnS-GSH QDs can effectively label cell membrane at neutral pH within 30 min and exhibit excellent optical stability in continuous imaging for up to 60 min.With the test concentration up to 200 nM,CdSe@ZnS-GSH QDs show high biocompatibility to cells and do not affect cell proliferation,disturb cell membrane integrity or cause apoptosis and necrosis of cells.Then,a two-component voltage sensor strategy based on fluorescence resonance energy transfer (FRET) between CdSe@ZnS-GSH QDs and the dipicrylamine (DPA) is successfully developed to monitor the membrane potential by the fluorescence of CdSe@ZnS-GSH QDs.This study offers a facile strategy for labeling plasma membrane and monitoring the membrane potential of cells and will hold great potential in the research of signaling within intact neuronal circuits. 展开更多
关键词 quantum DOTS MEMBRANE LABELING MEMBRANE potential IMAGING fluorescence IMAGING neuron
利用简易方法制备稳定的具有微纳结构的ZIF-8高效油水分离膜(英文)
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作者 宋明秋 赵宇鑫 +6 位作者 牟善军 姜春明 李湛 杨平平 方千荣 薛铭 裘式纶 《中国科学:材料科学(英文版)》 CSCD 2019年第4期536-544,共9页
在常温常压条件下,以金属网为载体,成功地制备出表面具有微纳结构的ZIF-8分离膜,该膜显示出优异的水下超疏油性能.该方法制备的ZIF-8分离膜,可以高效地分离多种油水混合物,油水分离效率高达99.99%,同时具有较高的水通量10.2×104L m... 在常温常压条件下,以金属网为载体,成功地制备出表面具有微纳结构的ZIF-8分离膜,该膜显示出优异的水下超疏油性能.该方法制备的ZIF-8分离膜,可以高效地分离多种油水混合物,油水分离效率高达99.99%,同时具有较高的水通量10.2×104L m-2h-1,以及耐压性.进一步,通过高温处理以及多种常见有机溶剂浸泡,该膜仍然可以保持高效的油水分离性能,并且可以循环使用.由于制备方法简单,该类ZIF-8油水分离膜可以实现大面积制备,这对于油水分离的实际应用至关重要. 展开更多
关键词 MEMBRANE METAL-ORGANIC frameworks UNDERWATER superoleophobicity oil-water SEPARATION
Impact of bacterial chaperonin GroEL-GroES on bacteriorhodopsin folding and membrane integration
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作者 Xinwei Lu Baomei Xu +6 位作者 Haiyan Sun Junting Wei Haixia Chi Naseer Ullah Khan Xiaojuan Wang Xiaoqiang Wang Fang Huang 《生物物理学报:英文版》 CSCD 2019年第3期133-144,共12页
Our understanding of molecular chaperone function in membrane protein biogenesis lags far behind that in soluble protein biogenesis. Through a combined approach including isothermal titration calorimetry, UV-Vis spect... Our understanding of molecular chaperone function in membrane protein biogenesis lags far behind that in soluble protein biogenesis. Through a combined approach including isothermal titration calorimetry, UV-Vis spectroscopy, and fluorescence spectroscopy, the behavior of ATP-dependent chaperonin GroEL-GroES, a paradigmatic chaperone of soluble protein folding, was investigated in the refolding of membrane protein bacteriorhodopsin (BR) and its membrane insertion. We found that BR bound asymmetrically to the double-ring GroEL, w让h a much higher affinity when it was partially denatured. GroEL alone showed a clear influence on BR refolding, but the presence of ATP was necessary to significantly enhance both the rate and yield of the GroEL-mediated folding, in contrast to the adverse effect of GroES on the folding yield. However;synergy between ATP and GroES was shown to be required not only for releasing high-affinity BR species from GroEL, but also for unfolding and rescuing the misfolded conformers complexed to GroEL. This is consistent with the observation that maximum rate enhancement of BR refolding or assembly with the prepared inverted membrane vesicles was achieved when the complete chaperonin system was used. Our results support the iterative unfolding mechanism of GroEL activity previously proposed for soluble proteins, whereby GroEL might perform repeated unfolding and release of BR, thus offering additional opportunities for timely folding or membrane integration. This work provides important information on the convergence of folding of membrane and soluble proteins in light of folding pathways and the role of molecular chaperones. 展开更多
关键词 CHAPERONIN MEMBRANE PROTEIN MEMBRANE reconstitution PROTEIN FOLDING PROTEIN structure
Recent advances in acid-resistant zeolite T membranes for dehydration of organics
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作者 Yiwei Luo Waseem Raza +2 位作者 Jianhua Yang Liangqing Li Ying Lu 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第6期1449-1457,共9页
Zeolite membranes offer outstanding potentials in separation of many molecular mixtures due to their molecular sieving selectivity and the high thermal and mechanical stability that allow them to operate at harsh cond... Zeolite membranes offer outstanding potentials in separation of many molecular mixtures due to their molecular sieving selectivity and the high thermal and mechanical stability that allow them to operate at harsh conditions.Development of durable and high separation performance membranes with lower fabrication and operation cost are highly demanded for industrial applications. Zeolite T membrane possesses good acid-resistance with excellent hydrophilic properties as compared to NaA zeolite membrane and can be extended to industrial organic dehydrations under an acidic environment. In the present review the research advances in development of zeolite T membranes for the dehydration of organic mixtures in acidic conditions are summarized. Especially the low temperature synthesis, and epitaxial growth of the zeolite membrane with high performance are well addressed, besides emphasis is particularly placed on ensemble synthesis of hollow fiber zeolite T membrane module and its future prospects for industrial separations. 展开更多
关键词 DEHYDRATION of ORGANICS EPITAXIAL growth ZEOLITE T MEMBRANE MEMBRANE PERVAPORATION
Comparative studies on fouling of homogeneous anion exchange membranes by different structured organics in electrodialysis
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作者 Zhijuan Zhao Shaoyuan Shi +2 位作者 Hongbin Cao Yujiao Li Bart Van der Bruggen 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第3期218-228,共11页
Five negatively charged organic compounds with different structures, sodium methane sulfonate(MS), sodium benzene sulfonate(BS), sodium 6-hydroxynaphthalene-2-sulfonate(NSS), sodium dodecyl sulfate(SDS), and sodium do... Five negatively charged organic compounds with different structures, sodium methane sulfonate(MS), sodium benzene sulfonate(BS), sodium 6-hydroxynaphthalene-2-sulfonate(NSS), sodium dodecyl sulfate(SDS), and sodium dodecyl benzene sulfonate(SDBS), were used to examine the fouling of an anion exchange membrane(AEM) in electrodialysis(ED),to explore the effect of molecular characteristics on the fouling behavior on the AEM and changes in the surface and electrochemical properties of the AEM. Results indicated that the fouling degree of the AEM by the different organics followed the order:SDBS > SDS > NSS > BS > MS. SDBS and SDS formed a dense fouling layer on the surface of the AEM, which was the main factor in the much more severe membrane fouling, and completely restricted the transmembrane ion migration. The other three organics caused fouling of the AEM by adsorption on the surface and/or accumulation in the interlayer of the AEM, and exhibited almost no influence on the transmembrane ion migration. It was also concluded that the organics with benzene rings caused more severe fouling of the AEM due to the stronger affinity interaction and steric effect between the organics and the AEM compared with organics with aliphatic chains. 展开更多
关键词 ANION exchange MEMBRANE Different structural ORGANICS MEMBRANE FOULING Property characterization FOULING mechanism analyses
Electrochemical analysis and convection-enhanced mass transfer synergistic effect of MnO_x/Ti membrane electrode for alcohol oxidation
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作者 Hong Wang Xin Wei +3 位作者 Yujun Zhang Ronghua Ma Zhen Yin Jianxin Li 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期150-156,共7页
The different electrocatalytic reactors could be constructed for the electrocatalytic oxidation of 2,2,3,3-tetrafluoro-1-propanol(TFP) with two typical MnOx/Ti electrodes, i.e.the electrocatalytic membrane reactor(ECM... The different electrocatalytic reactors could be constructed for the electrocatalytic oxidation of 2,2,3,3-tetrafluoro-1-propanol(TFP) with two typical MnOx/Ti electrodes, i.e.the electrocatalytic membrane reactor(ECMR) with the Ti membrane electrode and the electrocatalytic reactor(ECR) with the traditional Ti plate electrode.For the electro-oxidation of TFP, the conversion with membrane electrode(70.1%) in the ECMR was 3.3 and 1.7 times higher than that of the membrane electrode without permeate flow(40.8%) in the ECMR and the plate electrode(21.5%) in the ECR, respectively.Obviously, the pore structure of membrane and convection-enhanced mass transfer in the ECMR dramatically improved the catalytic activity towards the electro-oxidation of TFP.The specific surface area of porous electrode was 2.22 m2·g-1.The surface area of plate electrode was 2.26 cm2(1.13 cm2× 2).In addition, the electrochemical results showed that the mass diffusion coefficient of the MnOx/Ti membrane electrode(1.80 × 10-6 cm2·s-1) could be increased to 6.87 × 10-6 cm2·s-1 at the certain flow rate with pump, confirming the lower resistance of mass transfer due to the convection-enhanced mass transfer during the operation of the ECMR.Hence, the porous structure and convection-enhanced mass transfer would improve the electrochemical property of the membrane electrode and the catalytic performance of the ECMR,which could give guideline for the design and application of the porous electrode and electrochemical reactor. 展开更多
关键词 Electrocatalytic MEMBRANE REACTOR (ECMR) MnOx/Ti MEMBRANE electrode Electro-oxidation of 2 2 3.3-tetrafluoro-1-propanol(TFP) ELECTROCHEMICAL REACTOR (ECR) ELECTROCHEMICAL measurement
Effect of chemical dose on phosphorus removal and membrane fouling control in a UCT-MBR
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作者 Guangrong Sun Chuanyi Zhang +3 位作者 Wei Li Limei Yuan Shilong He Liping Wang 《中国环境科学与工程前沿:英文版》 SCIE EI CAS CSCD 2019年第1期27-37,共11页
To enhance phosphorus removal and make the effluent meet the strict discharge level of total phosphorus (TP, 0.5 mg/L), flocculant dosing is frequently applied. In this study, the performance of aluminum sulfate dosin... To enhance phosphorus removal and make the effluent meet the strict discharge level of total phosphorus (TP, 0.5 mg/L), flocculant dosing is frequently applied. In this study, the performance of aluminum sulfate dosing in a University of Cape Town Membrane Bioreactor (UCT-MBR) was investigated, in terms of the nutrients removal performance, sludge characteristics and membrane fouling. The results indicated that the addition of aluminum sulfate into the aerobic reactor continuously had significantly enhanced phosphorus removal. Moreover, COD, NH4+^-N and TN removal were not affected and effluent all met the first level A criteria of GB18918-2002. In addition, the addition of aluminum sulfhte had improved the sludge activity slightly and reduced transmembrane pressure (TMP) increase rate from 1.13 KPa/d to 0.57 KPa/d effectively. The alleviation of membrane fouling was attributed to the increased average particle sizes and the decreased accumulation of the small sludge particles on membrane surface. Furthcnnorc, the decline of extracellular polymeric substance (EPS) concentration in mixed sludge liquid decreased its accumulation on membrane surface, resulting in the mitigation of membrane fouling directly. 展开更多
关键词 University of CAPE Town MEMBRANE BIOREACTOR (UCT-MBR) Enhanced nutrients removal Aluminum sulfate Sludge activity MEMBRANE FOULING
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