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A METHOD FOR DETERMINATION OF CONCENTRATION OF ATOMIC HYDROGEN PERMEATED IN MULTI-LAYER STRUCTURE WALL OF HYDROGENATION REACTORS
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作者 G. Ya X.Y Zhang and Y. L. Du(State Key Laboratory for Corrosion and Protection, Institute of Corrosion and Protection of Metals,The Chinese Academy of Sciences, Shenyang 110015, China)(Applied Chemistry Division of Sciences Institute, Shenyang Polytechni 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第6期0-0,0-0+0-0,共6页
It was proposed how the concentration distribution was calculated in the treble lager wall of hgdrogenation reactor according to the principle of hydrogen diffusion at the steady state in this paper. Based on the stea... It was proposed how the concentration distribution was calculated in the treble lager wall of hgdrogenation reactor according to the principle of hydrogen diffusion at the steady state in this paper. Based on the steady hydrogen permeation current density i∞ measund with the hydrogen probe at a given temperature, the hydmpen concentrationson the key interfaces and hydrogen distribution at any given mdial profile in the single, double or treble layer wall of hydrogenation reactor could be found by applying the presented equations throoph suitable parmeters ioput. The theoretical bases were provided for developing the nondestructive probing technique of the concentration of atomic hydmpen in the wallS of hydrogenation reactors. 展开更多
关键词 hydrogen permeation hydrogen distribution hydrogenation reactor mathematical method
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Dewatering of Scenedesmus obliquus Cultivation Substrate with Microfiltration:Potential and Challenges for Water Reuse and Effective Harvesting
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作者 Marco Malaguti Lorenzo Craveri +3 位作者 Francesco Ricceri Vincenzo Riggio Mariachiara Zanetti Alberto Tiraferri 《Engineering》 SCIE EI CAS CSCD 2024年第7期155-163,共9页
In the microalgae harvesting process,which includes a step for dewatering the algal suspension,directly reusing extracted water in situ would decrease the freshwater footprint of cultivation systems.Among various alga... In the microalgae harvesting process,which includes a step for dewatering the algal suspension,directly reusing extracted water in situ would decrease the freshwater footprint of cultivation systems.Among various algae harvesting techniques,membrane-based filtration has shown numerous advantages.This study evaluated the reuse of permeate streams derived from Scenedesmus obliquus(S.obliquus)biomass filtration under bench-scale and pilot-scale conditions.In particular,this study identified a series of challenges and mechanisms that influence the water reuse potential and the robustness of the membrane harvesting system.In a preliminary phase of this investigation,the health status of the initial biomass was found to have important implications for the harvesting performance and quality of the permeate stream to be reused;healthy biomass ensured better dewatering performance(i.e.,higher water fluxes)and higher quality of the permeate water streams.A series of bench-scale filtration experiments with different combinations of cross-flow velocity and pressure values were performed to identify the operative conditions that would maximize water productivity.The selected conditions,2.4 m·s^(-1)and 1.4 bar(1 bar=105 Pa),respectively,were then applied to drive pilot-scale microfiltration tests to reuse the collected permeate as a new cultivation medium for S.obliquus growth in a pilot-scale photobioreactor.The investigation revealed key differences between the behavior of the membrane systems at the two scales(bench and pilot).It indicated the potential for beneficial reuse of the permeate stream as the pilot-scale experiments ensured high harvesting performance and growth rates of biomass in permeate water that were highly similar to those recorded in the ideal cultivation medium.Finally,different nutrient reintegration protocols were investigated,revealing that both macro-and micro-nutrient levels are critical for the success of the reuse approach. 展开更多
关键词 Scenedesmus obliquus MICROFILTRATION Permeate reuse HARVESTING MICROALGAE PILOT-SCALE
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Electrifying Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) for focalized heating in oxygen transport membranes
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作者 Marwan Laqdiem Julio García-Fayos +6 位作者 Laura Almar Alfonso J.Carrillo Álvaro Represa JoséM.López Nieto Sonia Escolástico David Catalán-Martinez Jose M.Serra 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期99-110,共12页
Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind electricity.In the case of pure oxygen production... Industry decarbonization requires the development of highly efficient and flexible technologies relying on renewable energy resources,especially biomass and solar/wind electricity.In the case of pure oxygen production,oxygen transport membranes(OTMs)appear as an alternative technology for the cryogenic distillation of air,the industrially-established process of producing oxygen.Moreover,OTMs could provide oxygen from different sources(air,water,CO_(2),etc.),and they are more flexible in adapting to current processes,producing oxygen at 700^(-1)000℃.Furthermore,OTMs can be integrated into catalytic membrane reactors,providing new pathways for different processes.The first part of this study was focused on electrification on a traditional OTM material(Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)),imposing different electric currents/voltages along a capillary membrane.Thanks to the emerging Joule effect,the membrane-surface temperature and the associated O_(2) permeation flux could be adjusted.Here,the OTM is electrically and locally heated and reaches 900℃on the surface,whereas the surrounding of the membrane was maintained at 650℃.The O_(2)permeation flux reached for the electrified membranes was~3.7 NmL min^(-1)cm^(-2),corresponding to the flux obtained with an OTM non-electrified at 900℃.The influence of depositing a porous Ce_(0.8)Tb_(0.2)O_(2-δ) catalytic/protective layer on the outer membrane surface revealed that lower surface temperatures(830℃)were detected at the same imposed electric power.Finally,the electrification concept was demonstrated in a catalytic membrane reactor(CMR)where the oxidative dehydrogenation of ethane(ODHE)was carried out.ODHE reaction is very sensitive to temperature,and here,we demonstrate an improvement of the ethylene yield by reaching moderate temperatures in the reaction chamber while the O_(2) injection into the reaction can be easily fine-tuned. 展开更多
关键词 Oxygen permeation Oxidative dehydrogenation of ethane Oxygen transport membranes Joule effect Mixed ionic-electronic conductors Catalytic membrane reactors
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The effect of reactive plasticizer on viscoelastic and mechanical properties of solid rocket propellants based on different types of HTPB resin
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作者 Tihomir Kovacevic Slavko Mijatov +3 位作者 Jelena Grzetic Suzana Cakic Bojana Fidanovski Sasa Brzic 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期66-77,共12页
Conventional plasticizers deteriorate mechanical and viscoelastic properties of the propellants due to their migration upon aging and long-term storage,which affects reliability and safety properties during exploitati... Conventional plasticizers deteriorate mechanical and viscoelastic properties of the propellants due to their migration upon aging and long-term storage,which affects reliability and safety properties during exploitation.To address this issue,conventional plasticizer,dioctyl adipate(DOA),is replaced by reactive one,castor oil(CO).In addition,three different types of HTPB were used to obtain propellants with designed viscoelastic and mechanical properties.The CO increased propellants viscosity,without a significant impact on the propellant processability,regardless to the type of prepolymer.Conversely,mechanical properties were different depending on the type of resin,which were further analyzed by gel permeation chromatography(GPC).Addition of CO formed a denser polymer network and shifted T_(g) to higher values,compared to the compositions with DOA.The tensile strength of CO-containing propellants was lower at +20℃ and +50℃ compared to the reference compositions,while the strain at maximum load and strain at break were significantly increased with pronounced plastic deformation,especially for samples at -30℃.The inclusion of CO in the propellants composition gives more room for adjusting a wide range of mechanical properties. 展开更多
关键词 HTPB-based composite propellants Castor oil Reactive plasticizer Gel permeation chromatography Sol-gel analysis Mechanical and viscoelastic properties
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Determination of 14 Organophosphorus Pesticide Residues in Mutton by Gel Permeation Chromatography-Gas Chromatography-Mass Spectrometry(GPC-GC-MS)
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作者 Junpeng ZHAO Richard Avoi +2 位作者 Azman Bin Atil@Azmi Jiao CHEN Ling YUN 《Agricultural Biotechnology》 2024年第3期28-30,33,共4页
[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by ga... [Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry(GC-MS)in selective ion scanning mode(SIM).[Results]The organophosphorus pesticide standard solutions showed good linearity in the mass concentration range of 0.1-10.0μg/ml with correlation coefficients(r)not lower than 0.999,and the detection limits(S=3 N)ranged from 0.01 to 0.05 mg/kg.The average recovery values were in the range of 80.2%-99.7%,with relative standard deviations(RSDs,n=3)in the range of 1.8%-6.3%,at the addition levels of 0.5,1.0 and 2.0 mg/kg.[Conclusions]The method is simple,sensitive and accurate,and can be used for the determination of organophosphorus pesticide residues in mutton. 展开更多
关键词 MUTTON Gas chromatography-mass spectrometry Gel permeation chromatography ORGANOPHOSPHORUS Pesticide residue
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Dissecting Multiple Arabidopsis CC-NBS-LRR Proteins Structure and Localization
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作者 Jianzhong Huang Xiuying Guan +6 位作者 Xiaoju Zhong Peng Jia Hongbin Zhang Kai Chen Zhuojun Li Guangyu Chen Chuitang Zeng 《Journal of Biosciences and Medicines》 2024年第7期87-99,共13页
NBS-LRR (nucleotide binding sites and leucine rich repeat) protein plays a crucial role as sentries and as defense activators in plants. The structure and function of NBS-LRR proteins are closely related. Previous art... NBS-LRR (nucleotide binding sites and leucine rich repeat) protein plays a crucial role as sentries and as defense activators in plants. The structure and function of NBS-LRR proteins are closely related. Previous articles have announced that the activated ZAR1 (HopZ-Activated Resistance 1) forms a pentamer in the plasma membrane, which is a calcium permeable channel that can trigger plant immune signaling and cell death. However, the structure of galore NBS-LRRs in Arabidopsis is not yet clear. The functional sites of distinct NBS-LRR in cells may vary. In addition, identifying pathogens and activating defense regions may occur in different subcellular compartments. Therefore, dissecting the specific structure and positioning of NBS-LRRs is an indispensable step in understanding their functions. In this article, we exploit AlphaFold to predict the structure of some designed NBS-LRRs, and utilize Agroinfiltration transient expression system, combined with biochemical fractionation, to dissect the localization of these NBS-LRR receptors from Arabidopsis. Structural data indicates that the identified NBS-LRRs share analogous conformation. Membrane fractionation assay demonstrates these NBS-LRRs are mainly associated with the membrane. These data show that the Ca2+-permeable channel activity may be evolutionarily conserved in NBS-LRR of Arabidopsis, and this study provides some reference clues for analyzing the structure and localization patterns of other plant immune receptors. 展开更多
关键词 ARABIDOPSIS Calcium Permeation Channel PENTAMER Plasma Membrane
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Research Progress on Application of Borneol As Permeation Enhancer in Functional Cosmetics
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作者 Xu Yuanyu Chen Yuxu +4 位作者 Zhang Jingqing Zhao Zhimin Yang Depo Xu Xinjun Wang Shidong 《China Detergent & Cosmetics》 CAS 2024年第1期71-75,共5页
Borneol, as a traditional natural permeation enhancer, has been widely used to promote the transdermal absorption of active ingredients. In this review, the mechanism of borneol in promoting permeation by destroying t... Borneol, as a traditional natural permeation enhancer, has been widely used to promote the transdermal absorption of active ingredients. In this review, the mechanism of borneol in promoting permeation by destroying the highly ordered lipid structure of the lipid layer and by destroying the hydrogen-bond network was described. The application of borneol in promoting the transdermal absorption of the active ingredients of traditional Chinese medicine and chemical drugs was introduced. The application of borneol as a natural ingredient added to functional cosmetics was summarized, and its effects on skin-spot treatment, acne skin care, eczema skin care, skin repair and anti-oxidation were introduced. Finally, the possible problems in the application of borneol in cosmetics were put forward, and the application prospect of borneol in the development of cosmetics was given. 展开更多
关键词 BORNEOL permeation enhancer COSMETICS
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The efficacy study of trinity permeation synergism on anti-aging
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作者 Ruifang Han Shuyu Wang +4 位作者 Juntong Li Meifang Wu Jian Zhou Peibiao Zhao Bin Cui 《Journal of Dermatologic Science and Cosmetic Technology》 2024年第3期40-48,共9页
Background:More and more consumers are paying attention to skin rejuvenation.However,there is a lack of a non-invasive and efficient solution.Objective:To evaluate the efficacy of a trinity permeation synergism(TPS),w... Background:More and more consumers are paying attention to skin rejuvenation.However,there is a lack of a non-invasive and efficient solution.Objective:To evaluate the efficacy of a trinity permeation synergism(TPS),which consists of a firming essence,an atomizer and a photoelectric penetrator,for facial anti-aging efficacy.Material and methods:In this work,in vitro cell experiments and human efficacy study were used to evaluate the firming and anti-wrinkle effects.Cell experiments were used to verify the effect of the firming essence on the cell proliferation,migration,and anti-inflammation in keratinocytes(HaCaT),and on the gene expression levels of type I and type III collagen(Col-1 and Col-3)and type I matrix metalloproteinase(MMP-1)in human skin fibroblasts(HSF).After in vitro test,60 women aged 35–60 years were enrolled in the randomized test,of which 30 subjects were randomly selected to be the experimental group and treated with the TPS system,while the left 30 subjects were treated with the firming essence only considered as control.After 28 days,skin elasticity,skin redness value,and skin wrinkles were measured to evaluate the efficacy of the TPS system.Results:Cell experiments showed that the firming essence can significantly improve the proliferation and the migration of HaCaT cells.It also promoted the expression level of Col-1 and Col-3 gene,and inhibited the expression level of MMP-1 gene in HSF cells.After confirming the efficacy of firming essence,the efficacy benefit of the TPS was further studied.The 28-day tests show that combined use firming essence with atomizer and penetrator can significantly increase skin elasticity,reduce skin hemoglobin value and skin wrinkles on Day 28.Moreover,all the mentioned improvements are significantly better than that in the control group.Conclusion:Through efficient delivery in the whole process,TPS boosts the efficacy of active components in the firming essence.TPS offers an efficient,non-invasive,and convenient way for enhanced facial rejuvenation efficacy. 展开更多
关键词 Trinity permeation synergism Facial rejuvenation Beauty device Firming and anti-wrinkle Synergistic effect
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An Overview of Soil Improvement through Ground Grouting
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作者 Md Ratan Bhuiyan Salequr Rahman Masum +1 位作者 Md Tushar Parvej S M Sanuwar 《Journal of Geoscience and Environment Protection》 2024年第1期51-63,共13页
Soil is an essential component of what surrounds us in nature, providing as the basis for our infrastructure and construction. However, soil is not always suitable for construction due to a variety of geotechnical iss... Soil is an essential component of what surrounds us in nature, providing as the basis for our infrastructure and construction. However, soil is not always suitable for construction due to a variety of geotechnical issues such as inadequate bearing capacity, excessive settlement, and liquefaction susceptibility. Through improving the engineering qualities of soil, such as strength, permeability, and stability, ground grouting is a specific geotechnical method used. Using a fluid grout mixture injected into the subsurface, holes are filled and weak or loose strata are solidified as the material seeps into the soil matrix. The approach’s adaptability in addressing soil-related issues has made it more well-known in the fields of civil engineering and construction. In the end, this has improved groundwater management, foundation support, and overall geotechnical performance. 展开更多
关键词 GROUTING Soil Improvement Permeation Grouting Compaction Grouting and Jet Grouting
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凝胶渗透色谱和气相色谱-质谱法测定动物食品中27种有机氯和15种拟除虫菊酯类农药残留量 被引量:15
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作者 王云凤 常春艳 +3 位作者 陈其勇 葛宝坤 高健会 宓捷波 《分析测试学报》 CAS CSCD 北大核心 2007年第z1期253-255,258,共4页
A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extractio... A GC-MS method for the determination of 27 organochlorine pesticides and 15 Pyrethroid pesticides in animal food is established.The method was based on Gel Permeation chromatography combined with solid-phase extraction for sample preparation.Rapid qualitative and quantitative analyses was carried out by gas chromatography-mass spectrometry under the selective-ion monitoring mode.The experimental results showed that the correlation coefficients were better than 0.99,the recoveries for spiked standards were 70%-104%,the relative standard deviations were 2.1%-15.9%. 展开更多
关键词 Organochlorine pesticides Pyrethroid pesticides Gel Permeation chromatography Solid-phase extraction Gas chromatography-mass spectrometry Animal food
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Study on ternary polymerization of toluene diisocyanate 被引量:1
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作者 祁争健 罗振扬 +4 位作者 李祥新 孙岳明 冯卫东 王华林 颜大志 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期265-269,共5页
For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene (TDI) terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups,... For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene (TDI) terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups, was synthesized and characterized by the Fourier transform infrared (FFIR), the gel permeation chromatography (GPC) and the chemical analysis methods. The reaction conditions were studied and optimized. A tracking research on the polymerization process of TDI was taken by using the GPC. The formation processes of the terpolymer, oligomers and higher-polymers were also dealt with. Results show that the TDI terpolymer can be prepared in the presence of Cat-3 catalyst and at the reaction temperature of (60 ±2)℃. The reaction time is short, its outcomes have narrow molecular weights distribution, namely molecular weights from 530 to 550, Mw/Mn =1.10, and the mass fraction of NCO is (25. 0 ± 0. 5)%. With the reaction time prolonging, however, TDI can be further higher-polymedzed to form higher-polymers. Benzoyl chloride (0. 4%, mass fraction), as the stabilizing agent, can effectively inhibit the occurrence of higher-polymerization. The obtained TDI terpolymer can be stable for more than half a year. 展开更多
关键词 2 4-diisocyanate toluene TERPOLYMER gel permeation chromatography curing agent storage stability
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The Effect of pH on the Permeation of Lidocaine Hydrochloride Across Excised Rat Skin
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作者 贾士聪 丁平田 +2 位作者 郑俊民 吴翠栓 华士元 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期133-135,共3页
The effect of pH on the permeation of Lidocaine hydrochloride (LH) across excised rat skin was studied, the steady state flux (JSS) at different pH being determined using improved Valia-Chien diffusion cells. JSS incr... The effect of pH on the permeation of Lidocaine hydrochloride (LH) across excised rat skin was studied, the steady state flux (JSS) at different pH being determined using improved Valia-Chien diffusion cells. JSS increased substantially when pH was close to the pKa of LH. The profile of JSS versus pH showed an 慡?shaped curve. JSS of Lidocaine free base (LFB) was fourteen times that of LH. The pH of vehicle influences the permeation of LH significantly and should be considered as an important factor when a formulation is developed. 展开更多
关键词 PH PKA LIDOCAINE PERMEATION
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高水平大学建设下高校文理渗透人才培养模式探析
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作者 王鹤岩 孙婧 白海艳 《大庆师范学院学报》 2014年第2期143-146,共4页
长期以来,我国高校面临着学科分化严重的现象,使得我国高水平大学建设中人才培养模式问题凸显出来。高水平大学建设要求高校人才培养模式要加强学与思的结合、知与行的统一,加强学生基础知识、专业知识和实践能力的培养。文理渗透是实... 长期以来,我国高校面临着学科分化严重的现象,使得我国高水平大学建设中人才培养模式问题凸显出来。高水平大学建设要求高校人才培养模式要加强学与思的结合、知与行的统一,加强学生基础知识、专业知识和实践能力的培养。文理渗透是实施科教兴国和人才强国相结合的综合素质教育,是未来社会对人才的基本要求,因此,我国高水平大学建设应该在转换教育观念、优化课程结构、加强师资队伍建设和丰富校园文化方面建设一个文理渗透的育人环境。 展开更多
关键词 高水平大学 文理渗透 人才培养模式 PERMEATION of " LIBERAL ARTS and Science"
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Effect of Molybdenum Doping on Oxygen Permeation Properties and Chemical Stability of SrCo0.8Fe0.2O3-δ
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作者 宋春林 方曙民 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期445-449,J0002,共6页
The phase composition, microstructure, thermal expansion coefficients, oxygen permeation properties and chemical stability of SrCo0.8Fe0.2O3-δ (SCFM) were investigated and compared with those of SrCo0.8Fe0.2O3-δ(... The phase composition, microstructure, thermal expansion coefficients, oxygen permeation properties and chemical stability of SrCo0.8Fe0.2O3-δ (SCFM) were investigated and compared with those of SrCo0.8Fe0.2O3-δ(SCF). Single phase SCFM was successfully prepared by a combined EDTA-citric method. SCFM shows a lower thermal expansion coefficient (24× 10^-6-29× 10^-6/K) than SCF between 500 and 1050 ℃, indicating a more stable structure. SCFM shows a high oxygen permeation flux, although the oxygen flux of SCFM decreases slightly because of Mo dopant. Furthermore, it was demonstrated that the doping of Mo in SCF can prevent the order-disorder transition and improves the chemical stability to CO2. 展开更多
关键词 Oxygen permeation SrCo0.8Fe0.2O3-δ Chemical stability MOLYBDENUM
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Microstructure and Element Profile of Rare Earth Permeating Layer of Al Bronze
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作者 朱小龙 刘庆华 +1 位作者 赵争荣 吴忍 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第4期281-285,共5页
Rare earth (RE) atoms were permeated into the surface of Al bronze (Cu-7. gA1-1. 9 Sn) by the method of chemical heat treatment. The permeated layer was then analysed by TEM (Transmission Electron Microscope) , EPMA (... Rare earth (RE) atoms were permeated into the surface of Al bronze (Cu-7. gA1-1. 9 Sn) by the method of chemical heat treatment. The permeated layer was then analysed by TEM (Transmission Electron Microscope) , EPMA (Electronic Probe Microanalysis) and IMA (Ion Microprobe Appratus). The results show that CuREAl and dispersed η phase (Cu6Sn5) distribute in the layer, RE content decreases in the depth direction, and alloying elements (Al, Sn) are enriched in the outer layer and dilute in the second layer. 展开更多
关键词 Al bronze Rare earth permeating permeated layer
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Fouling Characteristics and Prevention Techniques for Membrane Bioreactor
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作者 LUHua WANGZhi-qiang YANGJin-ying 《Journal of China University of Mining and Technology》 EI 2005年第1期36-40,共5页
Membrane fouling is the main problem of membrane bioreactors (MBR), which seriously influ- ences its wastewater treatment effect and running. The characteristics of microbiology and hydrodynamics concerning membrane f... Membrane fouling is the main problem of membrane bioreactors (MBR), which seriously influ- ences its wastewater treatment effect and running. The characteristics of microbiology and hydrodynamics concerning membrane fouling were investigated and the measure was put forward for optimum operation of MBR. The measure is that 1) the parameters of activated sludge concentration (X) and membrane flux should be lower than the critical values of X and membrane flux respectively, and 2) the activated sludge should be discharged periodically. The experimental results show that the combination backwashing of gas and perme- ated effluent is better than single gas backwashing or single permeated effluent backwashing. This technique can remove the cake layer deposited on the membrane surface, decrease the membrane fouling, and recover the membrane flux effectively. So it is effective for prevention of membrane fouling. 展开更多
关键词 membrane bioreactor (MBR) membrane fouling membrane fouling index BACKWASHING ratio of gas to permeated effluent
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凝胶渗透色谱-高效液相色谱-线性离子阱质谱法测定膳食样品中的氨基甲酸酯类农药残留 被引量:9
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作者 杨欣 李鹏 +2 位作者 苗虹 赵云峰 吴永宁 《色谱》 CAS CSCD 北大核心 2014年第5期499-505,共7页
建立了高效液相色谱-线性离子阱质谱( HPLC-LIT-MS)测定膳食样品中氨基甲酸酯类农药的检测方法。样品中加入同位素内标,用正己烷饱和的乙腈超声提取,凝胶渗透色谱净化。以乙腈和含5 mmol/L 甲酸铵和0.1%(v/v)甲酸的水溶液为流动... 建立了高效液相色谱-线性离子阱质谱( HPLC-LIT-MS)测定膳食样品中氨基甲酸酯类农药的检测方法。样品中加入同位素内标,用正己烷饱和的乙腈超声提取,凝胶渗透色谱净化。以乙腈和含5 mmol/L 甲酸铵和0.1%(v/v)甲酸的水溶液为流动相,目标化合物经 CAPCELL PAK CR(100 mm&#215;2.1 mm,5μm;SCX-C18(1:4))色谱柱分离,梯度洗脱,流速0.2 mL/min。采用电喷雾电离,选择反应监测( SRM)正离子模式三级离子监测。内标法定量。膳食类样品中氨基甲酸酯农药的平均加标回收率在60.4%~114%之间;相对标准偏差在3.46%~16.2%范围内;检出限( LODs)在0.001~0.010 mg/kg之间。应用所建立的方法对2007年第四次中国总膳食研究项目的9类膳食样品基质中的氨基甲酸酯类农药进行了检测,在少量样品中检出了涕灭威和克百威。 展开更多
关键词 凝胶渗透色谱 高效液相色谱-线性离子阱质谱 氨基甲酸酯类农药 膳食 gel PERMEATION chromatography( GPC) high performance liquid CHROMATOGRAPHY ( HPLC) linear ion trap mass spectrometry( LIT-MS)
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Effect of the Ultrasound Generated by Flat Plate Transducer Cleaning on Polluted Polyvinylidenefluoride Hollow Fiber Ultrafiltration Membrane 被引量:7
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作者 晋卫 郭伟 +2 位作者 吕效平 韩萍芳 王延儒 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第5期801-804,共4页
Polyvinylidenefluoride (PVDF) hollow fiber ultrafiltration membrane is frequently employed in water treatment. However, the fouling of ultrafiltration membranes affects the economic effectiveness of such process sig... Polyvinylidenefluoride (PVDF) hollow fiber ultrafiltration membrane is frequently employed in water treatment. However, the fouling of ultrafiltration membranes affects the economic effectiveness of such process significantly. The ultrasound generated by flat plate transducer (UFPT) was used to clean the polluted PVDF ultrafiltration membrane with 2 g·L^-1 of citric acid aqueous solution in our study. The effects of UFPT intensity on the membrane surface were studied. The new membrane was easy to be polluted by the saturated CaCl2 solution. A synergistic effect of UFPT and 2 g·L^-1 citric acid aqueous solution could remove the foul of the membrane, and its flux could be recovered about 81%. The flux recovery of old membrane polluted was increased to 73.2% after 7 h soaking in citric acid aqueous solution, but its flux recovery without soaking was only increased to 56.2%. 展开更多
关键词 ULTRASOUND membrane ULTRAFILTRATION CLEANING permeate flux
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Permeability and Selectivity of Sulfur Dioxide and Carbon Dioxide in Supported Ionic Liquid Membranes 被引量:9
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作者 江滢滢 吴有庭 +3 位作者 王文婷 李磊 周政 张志炳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第4期594-601,共8页
Permeabilities and selectivities of gases such as carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen (N2) and methane (CH4) in six imidazolium-based ionic liquids ([emim][BF4], [bmim][BF4], [bmim][PF6], [ba... Permeabilities and selectivities of gases such as carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen (N2) and methane (CH4) in six imidazolium-based ionic liquids ([emim][BF4], [bmim][BF4], [bmim][PF6], [banim][BF4], [bmim][Tf2N] and [emim][CF3SO3]) supported on polyethersulfone microfiltration membranes are investigated in a single gas feed system using nitrogen as the environment and reference component at temperature from 25 to 45℃ and pressure of N2 from 100 to 400 kPa. It is found that SO2 has the highest permeability in the tested supported ionic liquid membranes, being an order of magnitude higher than that of CO2, and about 2 to 3 orders of magnitude larger than those of N2 and CH4. The observed selectivity of SO2 over the two ordinary gas components is also striking. It is shown experimentally that the dissolution and transport of gas components in the supported ionic liquid membranes, as well as the nature of ionic liquids play important roles in the gas permeation. A nonlinear increase of permeation rate with temperature and operation pressure is also observed for all sample gases. By considering the factors that influence the permeabilities and selectivities of CO2 and SO2, it is expected to develop an optimal supported ionic liquid membrane technology for the isolation of acidic gases in the near future. 展开更多
关键词 PERMEATION gas separation ionic liquid supported ionic liquid membrane acidic gas
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Experimental and CFD Study on the Role of Fluid Flow Pattern on Membrane Permeate Flux 被引量:7
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作者 A. Parvareh M. Rahimi +1 位作者 S. S. Madaeni A. A. Alsairafi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第1期18-25,共8页
This paper reports a study on the role of fluid flow pattern and dynamic pressure on the permeate flux through a micro filtration membrane in laboratory scale.For this purpose,a dead-end membrane cell equipped with a ... This paper reports a study on the role of fluid flow pattern and dynamic pressure on the permeate flux through a micro filtration membrane in laboratory scale.For this purpose,a dead-end membrane cell equipped with a marine type impeller was used.The impeller was set to rotate in the clockwise and counter clockwise directions with the same angular velocities in order to illustrate the effect of rotation direction on permeate flux.Consequently, permeate fluxes were measured at various impeller rotational speeds.The computational fluid dynamics(CFD)predicted dynamic pressure was related to the fluxes obtained in the experiments.Using the CFD modeling,it is proven that the change in dynamic pressure upon the membrane surface has direct effect on the permeate flux. 展开更多
关键词 MEMBRANE MICROFILTRATION computational fluid dynamics modeling permeate flux
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