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Chinese Journal of Chemical Engineering 2003年第5期11卷 583-588页

作者： Pallab Ghosh reverse osmosis division Central Salt and Marine Chemicals Research Institute Bhavnagar 364002 Gujarat India

Nanofiltration separation has become a popular technique for removing large organic molecules and inorganic substances from water. It is achieved by a combination of three mechanisms: electrostatic repulsion,sieving and diffusion. In the present work, a model based on irreversible thermodynamics is extended and used to estimate rejection of inorganic salts and organic substances. Binary systems are modeled, where the feed contains an ion that is much less permeable to the membrane as compared with the other ion. The two model parameters are estimated by fitting the model to the experimental data. Variation of these parameters with the composition of the feed is described by an empirical correlation. This work attempts to describe transport through the nanofiltration membranes bv a simple model.

关键词：不可逆过程热力学模型估算纳米过滤膜电解质有机化合物膜分离扩散静电推斥聚合膜位阻表面电荷

Taste masking of ofloxacin and formation of interpenetrating polymer network beads for sustained release

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Journal of Pharmaceutical Analysis 2017年第4期7卷 244-251页

作者： A. Michael Rajesh Kiritkumar Mangaldas Popat reverse osmosis membrane division Central Salt and Marine Chemicals Research InstituteCouncil of Scientific & Industrial Research (CSIR)G.B. MargBhavnagar 364 002India Academy of Scientific and Innovative Research Central Salt and Marine Chemicals Research InstituteCouncil of Scientific & Industrial Research (CSIR)G.B. MargBhavnagar 364 002India

The objective of this study was to carry out taste masking of ofloxacin(Ofl) by ion exchange resins(IERs)followed by sustained release of Ofl by forming interpenetrating polymer network(IPN) beads. Drug-resin complexes(DRCs) with three different ratios of Ofl to IERs(1:1, 1:2, 1:4) were prepared by batch method and investigated for in vivo and in vitro taste masking. DRC of methacrylic acid-divinyl benzene(MD) resin and Ofl prepared at a ratio of 1:4 was used to form IPN beads. IPN beads of MD 1:4 were prepared by following the ionic cross-linking method using sodium carboxymethyl xanthan gum(SCMXG) and SCMXG-sodium carboxymethyl cellulose(SCMXG-SCMC). IPN beads were characterized with FT-IR and further studied on sustained release of Ofl at different pH. In vivo taste masking carried out by human volunteers showed that MD 1:4 significantly reduced the bitterness of Ofl. Characterization studies such as FT-IR, DSC, P-XRD and taste masking showed that complex formation took place between drug and resin. In vitro study at gastric pH showed complete release of drug from MD 1:4 within 30 min whereas IPN beads took 5 h at gastric pH and 10 h at salivary pH for the complete release of drug. As the crosslinking increased the release kinetics changed into non-Fickian diffusion to zero-order release mechanism. MD 1:4 showed better performance for the taste masking of Ofl and IPNs beads prepared from it were found useful for the sustained release of Ofl at both the pH, indicating a versatile drug delivery system.

关键词： Ion exchange resins Ofloxacin in vivo & in vitro taste masking Interpenetrating polymer network Sustained release

Taste masking of ciprofloxacin by ion-exchange resin and sustain release at gastric-intestinal through interpenetrating polymer network

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Asian Journal of Pharmaceutical Sciences 2015年第4期10卷 331-340页

作者： A.Michael Rajesh Shreya A.Bhatt Harshad Brahmbhatt Pritpal Singh Anand Kiritkumar Mangaldas Popat reverse osmosis membrane division Central Salt and Marine Chemicals Research InstituteCouncil of Scientific&Industrial Research(CSIR)G.B.MargBhavnagar 364002India Analytical Discipline&Centralized Instrumentation Facility Central Salt and Marine Chemicals Research InstituteCouncil of Scientific&Industrial Research(CSIR)G.B.MargBhavnagar 364002India Academy of Scientific and Innovative Research Central Salt and Marine Chemicals Research InstituteCouncil of Scientific&Industrial Research(CSIR)G.B.MargBhavnagar 364002India

The aim of the study was to taste mask ciprofloxacin(CP)by using ion-exchange resins(IERs)followed by sustain release of CP by forming interpenetrating polymer network(IPN).IERs based on the copolymerization of acrylic acid with different cross linking agents were synthesised.Drug-resin complexes(DRCs)with three different ratios of drug to IERs(1:1,1:2,1:4)were prepared&evaluated for taste masking by following in vivo and in vitro methods.Human volunteers graded ADC 1:4,acrylic acid-divinyl benzene(ADC-3)resin as tasteless.Characterization studies such as FTIR,SEM,DSC,P-XRD differentiated ADC 1:4,from physical mixture(PM 1:4)and confirmed the formation of complex.In vitro drug release of ADC 1:4 showed complete release of CP within 60 min at simulated gastric fluid(SGF)i.e.pH 1.2.IPN beads were prepared with ADC 1:4 by using sodium alginate(AL)and sodium alginate-chitosan(AL-CS)for sustain release of CP at SGF pH and followed by simulated intestinal fluid(SIF i.e.pH 7.4).FTIR spectra confirmed the formation of IPN beads.The release of CP was sustain at SGF pH(75%).The kinetic model of IPN beads showed the release of CP was non-Fickian diffusion type.

关键词： Ion exchange resins Biopolymers In vitro&in vivo taste masking Ciprofloxacin Sustain release Release mechanism and kinetics

Strategic comparison of membrane-assisted and membrane-less water electrolyzers and their potential application in direct seawater splitting(DSS)

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Green Energy & Environment 2023年第4期8卷 989-1005页

作者： Abdul Malek Xu Lu Paul R.Shearing Dan J.L.Brett Guanjie He Clean Combustion Research Center(CCRC) Physical Science and Engineering Division(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdom of Saudi Arabia KAUST Solar Center(KSC) Physical Science and Engineering Division(PSE)King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdom of Saudi Arabia School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondon E14NSUK Department of Chemical Engineering University College London(UCL)Gower StLondon WC1E 6BTUnited Kingdom

Electrocatalytic splitting of water by means of renewable energy as the electricity supply is one of the most promising methods for storing green renewable energy as hydrogen. Although two-thirds of the earth’s surface is covered with water, there is inadequacy of freshwater in most parts of the world. Hence, splitting seawater instead of freshwater could be a truly sustainable alternative. However, direct seawater splitting faces challenges because of the complex composition of seawater. The composition, and hence, the local chemistry of seawater may vary depending on its origin, and in most cases, tracking of the side reactions and standardizing and customizing the catalytic process will be an extra challenge. The corrosion of catalysts and competitive side reactions due to the presence of various inorganic and organic pollutants create challenges for developing stable electro-catalysts. Hence, seawater splitting generally involves a two-step process, i.e., purification of seawater using reverse osmosis and then subsequent fresh water splitting. However, this demands two separate chambers and larger space, and increases complexity of the reactor design. Recently, there have been efforts to directly split seawater without the reverse osmosis step. Herein, we represent the most recent innovative approaches to avoid the two-step process, and compare the potential application of membrane-assisted and membrane-less electrolyzers in direct seawater splitting(DSS). We particularly discuss the device engineering, and propose a novel electrolyzer design strategies for concentration gradient based membrane-less microfluidic electrolyzer.

关键词： Electrocatalytic seawater splitting Direct seawater splitting osmosis Concentration cells membrane-less electrolyzer Microfluidic electrolyzer

Innovative One Water Solutions for a Sustainable Water Supply

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Journal of Environmental Science and Engineering(B) 2022年第3期11卷 61-69页

作者： Alex Waite Sunny Wang Chris Aguillon Alex Nazarchuk City of Santa Monica Public Works:Water Resources division Santa MonicaCA 90404United States City of Santa Monica Public Works:Engineering division Santa MonicaCA 90404United States

Climate change impacts,such as higher average temperatures and prolonged drought conditions,have affected regional and local water supply reliability.The City of Santa Monica has long been a leader in promoting sustainability and is implementing several innovative water supply projects to develop alternative water supplies-including stormwater,dry weather urban runoff,and municipal wastewater-to provide a diverse,sustainable,and drought-resilient local water supply.The City is developing the first MBR(membrane Bioreactor)system and cartridge filtration system to receive log removal credits for potable reuse in the State of California,the first stormwater treatment project in the State of California that will augment groundwater supplies via direct injection,and the first municipal flow reversal RO(reverse osmosis)system in the United States.Collectively,these alternative water supplies sources will reduce the City’s reliance on imported water supplies and meet as much as 99%of its water demands through local water resources.

关键词： Self-sufficiency sustainability MBR flow reversal RO.

Mechanism involved in Danshen-induced fluid secretion in salivary glands

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World Journal of Gastroenterology 2015年第5期21卷 1444-1456页

作者： Fei Wei Mu-Xin Wei Masataka Murakami division of Physiological Sciences School of Life ScienceGraduate University for Advanced StudiesOkazaki 444-8585Japan Department of Traditional Chinese Medicine The first Affiliated Hospital with Nanjing Medical University division of Cellular Physiology National Institute for Physiological SciencesNational Institutes of Natural SciencesOkazaki 444-8787Japan

AIM:Danshen's capability to induce salivary fluid secretion and its mechanisms were studied to determine if it could improve xerostomia.METHODS:Submandibular glands were isolated from male Wistar rats under systemic anesthesia with pentobarbital sodium.The artery was cannulated and vascularly perfused at a constant rate.The excretory duct was also cannulated and the secreted saliva was weighed in a cup on an electronic balance.The weight of the accumulated saliva was measured every 3 s and the salivary flow rate was calculated.In addition,the arterio-venous difference in the partial oxygen pressure was measured as an indicator of oxygen consumption.In order to assess the mechanism involved in Dansheninduced fluid secretion,either ouabain(an inhibitor of Na+/K+ ATPase) or bumetanide(an inhibitor of NKCC1) was additionally applied during the Danshen stimulation.In order to examine the involvement of the main membrane receptors,atropine was added to block the M3 muscarinic receptors,or phentolamine was added to block the α1 adrenergic receptors.In order to examine the requirement for extracellular Ca2+,Danshen was applied during the perfusion with nominal Ca2+ free solution.RESULTS:Although Danshen induced salivary fluid secretion,88.7 ± 12.8 μL/g-min,n = 9,(the highest value around 20 min from start of DS perfusion was significantly high vs 32.5 ± 5.3 μL/g-min by carbamylcholine,P = 0.00093 by t-test) in the submandibular glands,the time course of that secretion differed from that induced by carbamylcholine.There was a latency associated with the fluid secretion induced by Danshen,followed by a gradual increasein the secretion to its highest value,which was in turn followed by a slow decline to a near zero level.The application of either ouabain or bumetanide inhibited the fluid secretion by 85% or 93%,and suppressed the oxygen consumption by 49% or 66%,respectively.These results indicated that Danshen activates Na+/K+ ATPase and NKCC1 to maintain Cl- release and K+ release for fluid secretion.Neither atropine or p

关键词： Salivary fluid secretion Xerostomia Chinese herb D

Potential of Magnesium Chloride for Nutrient Rejection in Forward osmosis

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Journal of Water Resource and Protection 2015年第9期7卷 730-740页

作者： Yatnanta Padma Devia Tsuyoshi Imai Takaya Higuchi Ariyo Kanno Koichi Yamamoto Masahiko Sekine Tuan Van Le division of Environmental Science and Engineering Graduate School of Science and Engineering Yamaguchi University Ube-shi Japan Department of Civil Engineering Brawijaya University Malang Indonesia division of Civil and Environmental Engineering Graduate School of Science and Engineering Yamaguchi University Ube-shi Japan Department of Environmental Science Hue University of Science Hue City Vietnam

Wastewater may contain high levels of the nutrients: nitrogen and phosphorus. Excessive release of nutrients to the environment can cause severe environmental problem such as eutrophication leading to algal blooms, oxygen deficiency, and fish kills. The forward osmosis (FO) could be a choice of treatment. FO process presents the results of using four kinds of variation in concentration of magnesium chloride (MgCl2) as draw solution and the two kinds of commercial membranes for nutrient rejection in the same cross flow velocity at 0.25 m/s and temperature at 25°C. Nutrients consisting of nitrogen (nitrite, nitrate, and ammonium) and phosphorus (phosphate) in feed solution were successfully rejected with an efficiency of mostly more 95%. The water flux in membrane HTI-NW achieved lower 7.55 - 9.61 L/m2·hr than in membrane HTI-ES that exceeds until 13.58 - 15.10 L/m2·hr. The reverse solute in membrane HTI-NW is seemly constant along all concentration of DS MgCl2 that the chloride diffusion is slightly higher than magnesium. In membrane HTI-ES, the reverse solute of chloride was almost three times than that of magnesium. The concentration of MgCl2 plays a significant role in rejecting nutrients by the Donnan’s potential and the diffusion constant in low and high concentration of DS, respectively.

关键词： Forward osmosis Magnesium Chloride Nutrient

超算与机器学习辅助高渗透性海水反渗透膜系统优化设计

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Science Bulletin 2023年第4期68卷 397-407,M0004页

作者：罗玖李明恒 Eric M.V.Hoek 衡益 School of Computer Science and Engineering Sun Yat-sen UniversityGuangzhou 510006China National Supercomputing Center in Guangzhou(NSCC-GZ) Guangzhou 510006China Guangdong Province Key Laboratory of Computational Science Guangzhou 510006China Department of Chemical and Materials Engineering California State Polytechnic UniversityPomona CA 91768USA Department of Civil&Environmental Engineering California NanoSystems Institute and Institute of the Environment&SustainabilityUniversity of CaliforniaLos Angeles(UCLA)Los Angeles CA 90095USA Energy Storage&Distributed Resources division Lawrence Berkeley National LaboratoryBerkeley CA 94720USA

当前,高渗透性反渗透膜材料的研究引起了广泛的关注,然而高渗透导致的浓差极化与膜污染加剧等瓶颈问题限制了高性能膜材料的应用发展.本工作采用机器学习结合超级计算提出了针对先进反渗透膜材料的组件进水隔网(亚毫米级)与系统(米级)... 详细信息

当前,高渗透性反渗透膜材料的研究引起了广泛的关注,然而高渗透导致的浓差极化与膜污染加剧等瓶颈问题限制了高性能膜材料的应用发展.本工作采用机器学习结合超级计算提出了针对先进反渗透膜材料的组件进水隔网(亚毫米级)与系统(米级)的多尺度优化设计新方法.在进料含盐度35,000 ppm,回收率50%典型工况下,对标目前国际先进海水反渗透淡化工艺,本文提出的优化方案能使淡水制备比能耗(1.66 k Wh/m^(3))降低27.5%,所需膜面积减少约37.2%,系统最大浓差极化因子控制在工程允许范围以内(<1.20),可有效缓解高渗透膜系统中膜污染问题,为高性能膜材料精准设计提供理论依据、计算工具和大数据支撑,有重要的应用潜力.本文提出的机器学习结合超算的多尺度设计新研究范式,突破了基于“试错法”的传统单一尺度组件设计限制,高通量并行计算规模可扩展至93,120核以上,较串行算法计算效率提升3000倍以上,可大幅度缩短高性能膜组件的设计周期.

关键词： reverse osmosis desalination High permeability membrane Multiscale design optimization Multilayer artificial neural networks Supercomputing Enhancement of mass transfer

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反渗透科学(英文)

膜科学与技术 1984年第1期 4-4页

作者： S.Sourirajan division of Chemistry National Research Council of Canada Ottawa

reverse osmosis is anew field of applied chemistry and chemical engineering which proven and potential applications are of enormous practical interest for the industrial progress of all nations, and for the health and welfare of all humanity. The object of this series of lectures is present in sufficient detail fundamental approach to research and development on reverse osmosis, ultrafiltration and synthetic membranes in all its aspects in Sourirajan’s laboratary. It includes the physicochemical nature of RO, basic transport equations and determination of solute transport parameters for predicting membrane performence in RO systems involving aqueous solutions and preferential sorption of water at membranesolution interfaces, applications of basic transport equations and solute transport parameters for systems involving mixed-solutes, the engineering science of RO and process design, surface force-pore flow model and their applications, materials science of RO/UF membranes. While there is still a long way to go towards the full development of the science of RO in all its aspects, considerable progress has already been made. This lecture series illustrates this progress and points to directions for new developments.

关键词： sorption solute humanity lecture welfare preferential predicting enormous interfaces nations