膜相渗透原位化学聚合法制备PAn/CA复合透膜

采用膜相渗透原位化学聚合法 ,使苯胺 ( An)原位化学聚合于醋酸纤维素 ( CA)基体膜的微孔壁中 ,得到均匀分布的 PAn/CA复合导电透膜 .通过研究聚合反应条件对复合透膜的导电性能和 CO2 /O2 表观分离性能的影响 ,获得了制备性能较优的 PAn/CA复合导电透膜的适宜条件 .结果表明 ,采用膜相渗透化学原位聚合法制备的 PAn/CA复合导电透膜 ,平均孔径明显变小 ,孔径分布变窄 ,具有优于 CA基体膜的微孔结构形态 .

导电聚合物复合透膜的研究进展

导电聚合物复合透膜具有良好的力学性能和独特的电化学性质,是一类新型的分离膜,已在膜分离技术、分子水平上的识别与控制等领域显示出了广阔的应用前景．本文介绍了导电透膜的合成制备方法、形态结构和分离机理,并对导电聚合物复合透膜的性能与结构研究进展以及在液体分离、气体分离方面的应用研究进行了综述．

舒胸舌下片制备与促透剂的配方

目的优选舒胸舌下片辅料配方和舌下黏膜促透剂配方。方法按正交实验设计,优选乳糖、甘露醇、微晶纤维素最佳比例;采用Frank扩散池进行体外扩散实验,HPLC测定人参皂苷Rg1的累积透膜量,按星点设计-效应面法设计实验,优选氮酮、油酸和薄荷醇的最佳比例。结果舌下片最佳制备工艺为药材提取物-〔乳糖-甘露醇(1∶9)〕-微晶纤维素为6∶8∶0.5加2%的氮酮、2%的油酸、5%薄荷醇复合促透剂制片。结论舒胸舌下片辅料配方能保证片剂的性状参数,复合黏膜促透作用稳定。

缠绕卷式膜曝气生物膜反应器工艺特性及农村污水处理应用实践

针对中国农村污水水量、水质、收集、输送、处理和排放特点,以及构造简单、维护方便、低碳节能、尾水回用等需求侧要求,介绍近年来应用的新型缠绕卷式膜曝气生物膜反应器(MABR)。从膜材质、膜结构、膜组件、传氧等方面,分析传氧效率、设备充氧动力效率等参数;从生物膜形态、泥膜组成形态、微生物载量特点、膜组件水力流态、组合工艺构成等方面,论述其复合“双泥”、高效脱氮除磷等优良工艺性能。结合工程实例,介绍该工艺在分散式农村污水处理中的可靠、高效、低维保应用和达标尾水资源化利用情况,以及农村废弃物协同低碳处理和资源化利用的实际需求。结合分散式农村污水处理装置低产泥需求,提出MABR耦合污泥减量菌实现源头污泥减量组合新工艺构想。基于该工艺超低能耗的运行特点,提出分类后污水生物质与农村其他可再生能源协同发电,并就地供应污水处理用电的建议,以期更好落实生物质分类处置,实现“无废乡村”愿景。

多孔不锈钢和透氢钯复合膜间扩散阻挡层研究进展

对金属多孔基体与钯复合膜间扩散阻挡层的研究现状进行综述,说明了扩散阻挡层在钯复合膜体系中的作用机理,探讨了金属互扩散发生的原因,对扩散阻挡层的主要制备方法进行了评述。

钯复合膜透氢稳定性的研究进展

本文针对钯复合膜透氢稳定性的研究,结合理论实践,先阐述了钯复合膜透氢机理,然后提出影响钯复合膜透氢稳定性的主要因素和控制方法,旨在提升钯复合膜透氢的稳定性。

应用生物模拟采样法快速评估水中邻苯二甲酸酯的生物富集性

利用三油酸甘油酯-醋酸纤维素半透复合膜(TECAM)对12种邻苯二甲酸酯类化合物(PAEs)进行微耗式快速富集试验(24 h),估算生物模拟采样方法对PAEs化合物的富集动力学参数以及富集系数,比较了膜富集系数(MCF)与生物富集系数(实验测定、模型预测)之间的相关性,及其随化合物的辛醇-水分配系数(KOW)的变化趋势。结果表明:(1)随着疏水性的增强,化合物在TECAM膜中具有不同的富集趋势:弱疏水性化合物能快速平衡,中疏水性化合物先经历线性富集阶段随后到达曲线富集阶段,中强疏水性化合物一直处于线性阶段;(2)膜对PAEs的富集系数随KOW的增加先上升后下降,与BCF随KOW的变化趋势一致,同时两种富集系数对KOW均符合二次曲线模型,并且MCF的相关性更好;(3)对MCF整体高于BCF的结果做出了解释——生物代谢使得BCF偏低,而TECAM对PAEs的富集不涉及代谢过程。尽管MCF不能表征生物体对邻苯二甲酸酯等可生物降解目标化合物的代谢过程,但该方法不受物种个体差异影响,具有估算水生生物富集目标化合物的潜在能力,更利于化合物之间的评估比较,并可作为对比研究生物代谢对BCF的影响。

Characterization of Energy_Transduction in Thermal Pretreated Chloroplast from Spinach

Characterization of energy-transduction on die chloroplast thylakoid membranes from spinach (Spinacia oleracca L.) after thermal pretreatment was investigated. The related reactions of energy-transduction in chloroplasts were seriously affected by thermal pretreatment. The results were obtained as following: (1) The rate of cyclic photophosphorylation declined when the pretreatment temperature increased in the range of 25 to 45 degreesC. (2) The thermal pretreatment led to a decrease of the activity of thylakoid membrane-bounded ATPase. (3) Proton uptake of chloroplasts acid the fluorescence quenching of 9-aminoacridine (9-AA) in thylakoid membrane decreased after the thermal pretreatment, but addition of dicyclohexylcarbodiimide (DCCD) could partially restore the fluorescence quenching of 9-AA. (4) Both the rates of fast phase in electrochroism absorption change at 515 nm and the millisecond delayed light emission (ms-DLE) of chloroplast showed a progressive decrease upon raising the temperature of pretreatment. (5) Immunbloting analysis showed that the thermal pretreatment caused the changes of protein content and the electrophoresis mobility of thylakoid membrane-bound ATPase and its alpha -subunit. (6) If the temperature of pretreatment were higher than 33 degreesC, oxygen uptake of PS I -mediated in the samples was rapidly inhibited, but addition of sinapine into the reaction medium could partially restore the ability of oxygen uptake in the samples. These results are briefly discussed in relation to the change of permeability of thylakoid membranes, the dissociation of coupling factor complex as well as accumulation of the radicals in the thylakoid membranes after thermal pretreatment.

Pervaporation Separation of Butanol-Water Mixtures Using Polydimethylsiloxane/Ceramic Composite Membrane

Pervaporation has attracted considerable interest owing to its potential application in recovering biobutanol from biomass acetone-butanol-ethanol (ABE) fermentation broth. In this study, butanol was recovered from its aqueous solution using a polydimethylsiloxane (PDMS)/ceramic composite pervaporation membrane. The effects of operating temperature, feed concentration, feed flow rate and operating time on the membrane pervaporation performance were investigated. It was found that with the increase of temperature or butanol concentration in the feed, the total flux through the membrane increased while the separation factor decreased slightly. As the feed flow rate increased, the total flux increased gradually while the separation factor changed little. At 40°C and 1% (by mass) butanol in the feed, the total flux and separation factor of the membrane reached 457.4 g·m?2·h?1 and 26.1, respectively. The membrane with high flux is suitable for recovering butanol from ABE fermentation broth.

Polymer/Ceramic Composite Membranes and Their Application in Pervaporation Process

Pervaporation(PV),as an environmental friendly and energy-saving separation technology,has been received increasing attention in recent years.This article reviews the preparation and application of macroporous ceramic-supported polymer composite pervaporation membranes.The separation materials of polymer/ceramic composite membranes presented here include hydrophobic polydimethylsiloxane(PDMS) and hydrophilic poly(vinyl alcohol)(PVA),chitosan(CS) and polyelectrolytes.The effects of ceramic support treatment,polymer solution properties,interfacial adhesion and incorporating or blending modification on the membrane structure and PV performance are discussed.Two in-situ characterization methods developed for polymer/ceramic composite membranes are also covered in the discussion.The applications of these composite membranes in pervaporation process are summarized as well,which contain the bio-fuels recovery,gasoline desulfuration and PV coupled proc-ess using PDMS/ceramic composite membrane,and dehydration of alcohols and esters using ceramic-supported PVA or PVA-CS composite membrane.Finally,a brief conclusion remark on polymer/ceramic composite mem-branes is given and possible future research is outlined.

Development of CO2 Selective Poly（Ethylene Oxide）-Based Membranes： From Laboratory to Pilot Plant Scale

Membrane gas separation is one of the most promising technologies for the separation of carbon dioxide （CO2） from various gas streams. One application of this technology is the treatment of flue gases from combustion processes for the purpose of carbon capture and storage. For this application, poly（ethylene oxide）-containing block copolymers such as Pebax or PolyActiveTM polymer are well suited. The thin-film composite membrane that is considered in this overview employs PolyActiveTM polymer as a selective layer material. The membrane shows excellent CO2 permeances of up to 4 m^3（STP）.（m^2·h·bar）^-1 （1 bar = 105 Pa） at a carbon dioxide/nitrogen （CO2/N2） selectivity exceeding 55 at ambient temperature. The membrane can be manufactured reproducibly on a pilot scale and mounted into fiat-sheet membrane modules of different designs. The operating performance of these modules can be accurately predicted by specifically developed simulation tools, which employ single-gas permeation data as the only experimental input. The performance of membranes and modules was investigated in different pilot plant studies, in which flue gas and biogas were used as the feed gas streams. The investigated processes showed a stable separation performance, indicating the applicability of PolyActiveTM polymer as a membrane material for industrialscale gas processing.

Thermal Stability of Silica-Zirconia Membranes

The thermal stability, phase transformation, surface morphology, pore size distribution and permeation of the defect-free silica-zirconia membrane were investigated by using X-ray diffraction （XRD）, atomic force microscopy （AFM）, gas adsorption analyzer （BET）, and gas permeation apparatus, respectively. Using silica as the stabilizing agent, the defect-free membrane was much more stable than pure zirconia. The crystal transformation of zirconia in the silica-stabilized membrane could be prohibited by the interaction between silica and zireonia. ZrO2 crystals were kept tetragonal below 900℃, the size of which did not change with temperature between 700℃ and 900℃. It was further verified by the AFM observation, pore size analysis and permeation study. This thermal stability makes the silica-zirconia membrane a good choice as the intermediate layer for zeolite and Pd-based membranes.

Fabrication of graphene oxide composite membranes and their application for pervaporation dehydration of butanol

As a new kind of2D nanomaterials, graphene oxide （GO） with 2-4 layers was fabricated rio a modified Hummers method and used for the preparation ofpervaporation （PV） membranes. Such GO membranes were prepared via a facile vacuum-assisted method on anodic aluminium oxide disks and applied for the dehydration of butanol. To obtain GO membranes with high performance, effects of pre-treatments, including high-speed centrifugal treat- ment of GO dispersion and thermal treatment of GO membranes, were investigated. In addition, effects of operation conditions on the performance of GO membranes in the PV process and the stability of GO membranes were also studied. It is of benefit to improve the selectivity of GO membrane by pre-treatment that centrifuges the GO dispersion with 10000 r· min^- 1 for 40 min, which could purify the GO dispersion by removing the large size GO sheets. As prepared GO membrane showed high separation performance for the butanol/water system. The separation factor was 230, and the permeability was as high as 3.1 kg·m^- 2·h^-1 when the PV temperature was 50 ℃ and the water content in feed was 10% （by mass）. Meanwhile, the membrane still showed good stability for the dehydration of butanol after running for 1800 min in the PV process. GO membranes are suitable candidates for butanol dehydration via PV process.

Permeation Characteristics of Light Hydrocarbons Through Poly（amide-6-β-ethylene oxide） Multilayer Composite Membranes

In this paper, poly(amide-6-β-ethylene oxide) (PEBA1657) copolymer was used to prepare multilayer polyetherimide (PEI)/polydimethylsiloxane (PDMS)/PEBA1657/PDMS composite membranes by dip-coating method. Permeation behaviors of ethylene, ethane, propylene, propane, n-butane, methane and nitrogen through the multilayer composite membranes were investigated over a range of operating temperature and pressure. The permeances of light hydrocarbons through PEI/PDMS/PEBA1657/PDMS composite membranes increase with their increasing condensability, and the olefins are more permeable than their corresponding paraffins. For light hydrocarbons, the gas permeances increase significantly as temperature increasing. When the transmembrane pressure difference increases, the gas permeance increases moderately due to plasticization effect, while their apparent activation energies for permeation decrease.

Sodium alginate-polyvinyl alcohol/polysulfone (SA-PVA/PSF) hollow fiber composite pervaporation membrane for dehydration of ethanol-water solution

Using polysulfone （PSF） hollow fiber ultrafiltration membranes as the substrate, sodium alginate （SA） and polyvinyl alcohol （PVA） blend solutions as the coating solution, and maleic anhydride （MAC） as the cross-linked agent, SAPVA/PSF hollow fiber composite membranes were prepared for the dehydration of ethanol-water. The effects of different sodium alginate concentration in the coating solutions and different operating temperatures on pervaporation performance were investigated. The experimental results showed that pervaporation performance of the SA-PVA/PSF composite membranes for ethanol-water solution exhibited a high separation factor although they had a relatively low permeation flux. As SA concentration in SA-PVA coating solution was 66.7% and the operating temperature was 40 ℃, SA-PVA/PSF hollow fiber composite membrane （PS4） had a separation factor of 886 and flux of 12.6 g/（m^2·h）. Besides, SA-PVA/PSF hollow fiber composite membranes （PS3 and PS4） were used for the investigation of the effect of ethanol concentration in the feed solution on pervaporation performance.

Outer membrane VDAC1 controls permeability transition of the inner mitochondrial membrane in cellulo during stress-induced apoptosis

Voltage-dependent anion channel （VDAC）I is the main channel of the mitochondrial outer membrane （MOM） and it has been proposed to be part of the permeability transition pore （PTP）, a putative multiprotein complex candidate agent of the mitochondrial permeability transition （MPT）. Working at the single live cell level, we found that overexpression of VDAC1 triggers MPT at the mitochondrial inner membrane （MIM）. Conversely, silencing VDAC1 ex- pression results in the inhibition of MPT caused by selenite-induced oxidative stress. This MOM-MIM crosstalk was modulated by Cyclosporin A and mitochondrial Cyclophilin D, but not by Bcl-2 and BcI-XL, indicative of PTP operation. VDAC1-dependent MPT engages a positive feedback loop involving reactive oxygen species and p38-MAPK, and secondarily triggers a canonical apoptotic response including Bax activation, cytochrome e release and caspase 3 activation. Our data thus support a model of the PTP complex involving VDAC1 at the MOM, and indicate that VDACl-dependent MPT is an upstream mechanism playing a causal role in oxidative stress-induced apoptosis.

Ceramic Supported PDMS and PEGDA Composite Membranes for CO2 Separation

Composite membranes have attracted increasing attentions owing to their potential applications for CO2 separation. In this work, ceramic supported polydimethylsiloxane （PDMS） and poly （ethylene glycol） diacrylate （PEGDA） composite membranes were prepared. The microstructure and physicochemical properties of the compos- ite membranes were characterized. Preparation conditions were systematically optimized. The gas separation performance of the as-prepared membranes was studied by pure gas and binary gas permeation measurement of CO〉 N2 and H〉 Experiments showed that PDMS, as silicone rubber, exhibited larger permeance and lower separation factors. Conversely, PEGDA composite membrane presented smaller gas permeance but higher ideal selectivity for CO2/N2. Compared to the performance of those membranes using polymeric supports or freestanding membranes, the two kinds of ceramic supported composite membranes exhibited higher gas permeance and acceptable selectivity. Therefore, the ceramic supported composite membrane can be expected as a candidate for CO2 separation from light gases.

Pervaporation of Aqueous Solution of Acetaldehyde Through ZSM-5 Filled PDMS Composite Membrane

Hydrophobic ZSM-5 zeolite filled polydimethylsiloxane （PDMS） composite membranes with Nylon micro-filtration membrane as the support layer were prepared to separate acetaldehyde from its aqueous solution. The composite membranes were characterized by Fourier transform infrared spectroscopy and X-ray diffraction. Their structural morphology and thermal stability were also examined. The swelling study showed that the composite membranes presented higher degree of swelling in aqueous solution of acetaldehyde than in pure water at 25℃,