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Engineering HOF‑Based Mixed‑Matrix Membranes for Efficient CO_(2) Separation 被引量:3
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作者 Yuhan Wang Yanxiong Ren +7 位作者 Yu Cao Xu Liang Guangwei He Hanze Ma Hongliang Dong Xiao Fang Fusheng Pan Zhongyi Jiang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第4期76-84,共9页
Hydrogen-bonded organic frameworks(HOFs)have emerged as a new class of crystalline porous materials,and their application in membrane technology needs to be explored.Herein,for the first time,we demonstrated the utili... Hydrogen-bonded organic frameworks(HOFs)have emerged as a new class of crystalline porous materials,and their application in membrane technology needs to be explored.Herein,for the first time,we demonstrated the utilization of HOF-based mixed-matrix membrane for CO_(2) separation.HOF-21,a unique metallo-hydrogen-bonded organic framework material,was designed and processed into nanofillers via amine modulator,uniformly dispersing with Pebax polymer.Featured with the mix-bonded framework,HOF-21 possessed moderate pore size of 0.35 nm and displayed excellent stability under humid feed gas.The chemical functions of multiple binding sites and continuous hydrogen-bonded network jointly facilitated the mass transport of CO_(2).The resulting HOF-21 mixed-matrix membrane exhibited a permeability above 750 Barrer,a selectivity of~40 for CO_(2)/CH_(4) and~60 for CO_(2)/N_(2),surpassing the 2008 Robeson upper bound.This work enlarges the family of mixed-matrix membranes and lays the foundation for HOF membrane development. 展开更多
关键词 Hydrogen-bonded organic framework Tunable size mixed-matrix membrane mixed-bond Carbon capture
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Enhance gas-separation efficiency of mixed matrix membranes by lamellarly arranged metal-organic polyhedron 被引量:1
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作者 Yida Yang Bowen Pang +5 位作者 Wang Zeng Bingxu Ma Panchao Yin Shenglin Yao Xiufang Wen Wei Zhang 《Nano Research》 SCIE EI CSCD 2023年第8期11450-11454,共5页
Eliminating the nonselective permeation path inside the mixed-matrix membranes(MMMs)is critical for fabrication of gas separation membranes.We demonstrate that by utilizing the phase separation of block copolymers,we ... Eliminating the nonselective permeation path inside the mixed-matrix membranes(MMMs)is critical for fabrication of gas separation membranes.We demonstrate that by utilizing the phase separation of block copolymers,we are able to introduce metal-organic polyhedrons(MOPs)with precise pore sizes into a polymer matrix and form an ordered layered structure.We also prove that,by arranging MOP cages into a continuous nanosheet-like layer structure,we are able to generate repeated MOP-effective pathways and deplete the MOP-free permeation pathways,thus enhancing the gas-separation efficiency of MMMs. 展开更多
关键词 metal-organic polyhedrons(MOPs) mixed-matrix membranes(MMMs) phase separation of mixed-matrix membranes arrangement of MOPs
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Regulation of interlayer channels of graphene oxide nanosheets in ultra-thin Pebax mixed-matrix membranes for CO_(2) capture
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作者 Feifan Yang Yuanhang Jin +5 位作者 Jiangying Liu Haipeng Zhu Rong Xu Fenjuan Xiangli Gongping Liu Wanqin Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期257-267,共11页
For the application of carbon capture by membrane process,it is crucial to develop a highly permeable CO_(2)-selective membrane.In this work,we reported an ultra-thin polyether-block-amide(Pebax)mixedmatrix membranes(... For the application of carbon capture by membrane process,it is crucial to develop a highly permeable CO_(2)-selective membrane.In this work,we reported an ultra-thin polyether-block-amide(Pebax)mixedmatrix membranes(MMMs)incorporated by graphene oxide(GO),in which the interlayer channels were regulated to optimize the CO_(2)/N_(2) separation performance.Various membrane preparation conditions were systematically investigated on the influence of the membrane structure and separation performance,including the lateral size of GO nanosheets,GO loading,thermal reduction temperature,and time.The results demonstrated that the precisely regulated interlayer channel of GO nanosheets can rapidly provide CO_(2)-selective transport channels due to the synergetic effects of size sieving and preferential adsorption.The GO/Pebax ultra-thin MMMs exhibited CO_(2)/N_(2) selectivity of 72 and CO_(2) permeance of 400 GPU(1 GPU=106 cm^(3)(STP)·cm^(2)·s^(-1)·cmHg^(-1)),providing a promising candidate for CO_(2) capture. 展开更多
关键词 mixed-matrix membrane Ultra-thin membrane Pebax Graphene oxide CO_(2) capture
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2D Cd-MOF and its mixed-matrix membranes for luminescence sensing antibiotics in various aqueous systems and visible fingerprint identifying 被引量:1
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作者 Kexin Ma Jing Li +7 位作者 Huiyan Ma Yan Yang Hua Yang Jing Lu Yunwu Li Jianmin Dou Suna Wang Suijun Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第11期321-325,共5页
The abuse of antibiotics has brought great harm to the human living environment and health,so it is extremely significant to develop an efficient and simple method to detect trace antibiotic residues in various wastew... The abuse of antibiotics has brought great harm to the human living environment and health,so it is extremely significant to develop an efficient and simple method to detect trace antibiotic residues in various wastewaters.Herein,a new two-dimensional(2D)Cd-based metal−organic framework(Cd-MOF,namely LCU-111)and its mixed matrix membranes(MMMs)is sifted as luminescence sensors for efficient monitoring antibiotic nitrofurazone(NFZ)in various aqueous systems and applied as visible fingerprint identifying.The LCU-111 has good selectivity,sensibility,reproducibility and anti-interference for luminescent quenching NFZ with low detection limits(LODs)of 0.4567,0.3649 and 0.8071 ppm in aqueous solution,HEPES biological buffer,and real urban Tuhai River water,respectively.Interestingly,the luminescent test papers and MMMs allow the NFZ sensing easier and more rapid by naked eyes,only with a low LOD of 0.8117 ppm for MMMs sensor.Notably,by combining multiple experiments with density functional theory(DFT)calculations,the photo-induced electron transfer(PET)quenching mechanism is further elucidated.More importantly,potential practical applications of LCU-111 for latent fingerprint visualization provide lifelike evidences for effective identification of individuals,which can be applied in criminal investigation. 展开更多
关键词 MOF luminescence sensor mixed-matrix membranes Real urban river water Antibiotic nitrofurazone Visible fingerprint identifying
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用于气体分离的含多孔材料的混合基质膜--从金属有机框架到离散分子笼
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作者 Ziqi Yang Zhongjie Wu +3 位作者 Shing Bo Peh Yunpan Ying Hao Yang Dan Zhao 《Engineering》 SCIE EI CAS CSCD 2023年第4期40-55,M0003,共17页
混合基质膜(MMMs)将多孔材料与聚合物基质相结合,因其互补特性和协同激活已经在气体分离领域引起了相当大的研究兴趣。多孔材料的可塑性和多样性赋予MMMs可延伸的功能和出色的分离性能。为了发挥MMMs的全部潜力,研究人员关注多孔填料与... 混合基质膜(MMMs)将多孔材料与聚合物基质相结合,因其互补特性和协同激活已经在气体分离领域引起了相当大的研究兴趣。多孔材料的可塑性和多样性赋予MMMs可延伸的功能和出色的分离性能。为了发挥MMMs的全部潜力,研究人员关注多孔填料与聚合物基质的合理匹配,以实现这些材料之间界面的增强相容性。在本文中,我们重点介绍采用不同策略将金属-有机框架(MOFs)和金属-有机笼(MOCs)与聚合物基质相结合制备MMMs的最新进展。文中进一步讨论未来MMMs发展所面临的机遇和挑战,并旨在通过合理的材料设计和选择推动MMMs的制备。 展开更多
关键词 Gas separation Metal-organic frameworks Metal-organic cages mixed-matrix membranes Interfacial compatibility
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Improved dispersion performance and interfacial compatibility of covalent-grafted MOFs in mixed-matrix membranes for gas separation 被引量:4
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作者 Chongqing Wang Guangjie Ren +5 位作者 Kaifeng Wei Donghui Liu Tingting Wu Jinlong Jiang Junfeng Qian Yichang Pan 《Green Chemical Engineering》 2021年第1期86-95,共10页
Mixed-matrix membranes(MMMs)have received much attention due to their processable advantages of polymer and high permeability and/or selectivity of porous metal-organic frameworks(MOFs)fillers.However,the interfacial ... Mixed-matrix membranes(MMMs)have received much attention due to their processable advantages of polymer and high permeability and/or selectivity of porous metal-organic frameworks(MOFs)fillers.However,the interfacial defects caused by poor interaction between MOFs with polymers and the agglomeration phenomenon caused by uneven dispersion of MOFs are common problems in mixed-matrix membranes.Currently,the priming protocol is one of solutions to the above problems,but it cannot precisely regulate the dispersion of particles and the interfacial compatibility between two phases.Herein,covalent grafting of polyimide 6FDA-Durene onto the surface of UiO-66-NH2 can mitigate the aggregation of fillers inside the polymeric matrices and improve the interfacial interaction between two phases,thus significantly improving the CO_(2)/CH_(4)separation performance on the as-synthesized MMMs.The explored gas transport mechanism indicated that the improved separation was due to the raise of solubility selectivity.Furthermore,the stronger covalent bond between fillers and polyimide than physical interaction of priming protocol also endows the improved anti-plasticization phenomenon for CO_(2)/CH_(4)separation. 展开更多
关键词 mixed-matrix membrane MOFS PRIMING Covalent grafting Interfacial compatibility
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数字波束形成雷达的天线方向图预置零技术(英文) 被引量:1
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作者 余啟波 FENáNDEZ Manuel F 《现代雷达》 CSCD 北大核心 2016年第12期1-8,15,共9页
基于数字波束形成体制的相控阵雷达系统,如果杂波和干扰的角度先验信息可以获知,则可采用方向图预置零技术进行相关的抑制处理。文中提出一种能够实现可控制方向图零陷宽度和零陷数量的处理方法。该方法采用对阵列方向图响应矩阵的奇异... 基于数字波束形成体制的相控阵雷达系统,如果杂波和干扰的角度先验信息可以获知,则可采用方向图预置零技术进行相关的抑制处理。文中提出一种能够实现可控制方向图零陷宽度和零陷数量的处理方法。该方法采用对阵列方向图响应矩阵的奇异值分解和重构,进行扩展的零空间基向量的求解。同时,针对提出的新方法的实际应用。 展开更多
关键词 天线方向图 阵列波束形成 阵列响应矩阵 零空间 阻塞矩阵 离散零陷 零陷扩展 混合矩阵 静态方向图
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Screening and design of COF-based mixed-matrix membrane for CH_(4)/N_(2) separation 被引量:1
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作者 Tongan Yan Dahuan Liu +1 位作者 Qingyuan Yang Chongli Zhong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第2期170-177,共8页
Membrane separation is a high-efficiency,energy-saving,and environment-friendly separation technology.Covalent organic framework(COF)-based mixed-matrix membranes(MMMs)have broad application prospects in gas separatio... Membrane separation is a high-efficiency,energy-saving,and environment-friendly separation technology.Covalent organic framework(COF)-based mixed-matrix membranes(MMMs)have broad application prospects in gas separation and are expected to provide new solutions for coal-bed methane purification.Herein,a high-throughput screening method is used to calculate and evaluate COF-based MMMs for CH_(4)/N_(2) separation.General design rules are proposed from thermodynamic and kinetic points of view using the computation-ready,experimental COFs.From our database containing 471,671 generated COFs,5 COF membrane materials were screened with excellent membrane selectivities,which were then used as the filler of MMMs for separation performance evaluation.Among them,BAR-NAP-Benzene_CF_(3) combined with polydimethylsiloxane and styrene-b-butadiene-b-styrene show high CH_(4) permeability of 4.43×10^(-13) mol·m·s^(-1)·Pa^(-1)·m^(-2) and high CH_(4)/N_(2) selectivity of 9.54,respectively.The obtained results may provide reasonable information for the design of COF-based membranes for the efficient separation of CH_(4)/N_(2). 展开更多
关键词 Covalent organic frameworks METHANE Molecular simulations mixed-matrix membrane Nitrogen SEPARATION
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Pore engineering of ZIF-8 with ionic liquids for membrane-based CO_(2)separation:bearing functional group effect 被引量:2
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作者 Zhengqing Zhang Xuemeng Jia +3 位作者 Yuxiu Sun Xiangyu Guo Hongliang Huang Chongli Zhong 《Green Chemical Engineering》 2021年第1期104-110,共7页
CO_(2)separation performance of polymer membranes can be significantly enhanced by selecting porous fillers with high CO_(2)affinity.Ionic liquids incorporation has been recognized as an effective strategy for improvi... CO_(2)separation performance of polymer membranes can be significantly enhanced by selecting porous fillers with high CO_(2)affinity.Ionic liquids incorporation has been recognized as an effective strategy for improving the separation ability of pristine porous fillers.However,the influence of the specific functional groups of ILs in IL@MOF composites on separation performance of MMMs still remains unclear.Herein,we designed three microenvironment-tuned IL@ZIF-8 composites in which the three ILs contain different functional groups(-CH3,–SO3H,and–NH2).Molecular simulation results showed that the NH2-IL@ZIF-8 has a commendable CO_(2)adsorption capacity and CO_(2)/CH4 adsorptive selectivity,and the results were well confirmed by the following experimental data.More importantly,the prepared NH2-IL@ZIF-8 based MMMs also exhibit superior CO_(2)separation performance among the three IL@ZIF-8 based MMMs owning to its high CO_(2)affinity.Thus,this work can provide guidance for designing IL@MOF composites for MMMs fabrication towards gas separation,and the research mode combining molecular simulation prediction and experimental verification can afford valuable reference for material development in membrane separation field. 展开更多
关键词 Molecular simulation Gas separation Ionic liquids ZIF-8 mixed-matrix membranes(MMMs)
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Formulation of Mixed-Matrix Membrane (PSF/Zeolite) for CO<SUB>2</SUB>/N<SUB>2</SUB>Separation: Screening of Polymer Concentration
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作者 Chen Chee Lek Sunarti Abd Rahman 《Journal of Materials Science and Chemical Engineering》 2015年第5期65-74,共10页
This research investigates the permeability of CO2 and N2 as well as selectivity of CO2 over N2 of polysulfone (PSF) mixed matrix membranes filled with zeolite 4&Aring particles. The membranes were prepared by sol... This research investigates the permeability of CO2 and N2 as well as selectivity of CO2 over N2 of polysulfone (PSF) mixed matrix membranes filled with zeolite 4&Aring particles. The membranes were prepared by solution-casting method and utilized to determine the permeation rates of N2 and CO2. It was characterized by FTIR and the gas separation performance was analysed by Design of Expert (DOE) method. FTIR result revealed the intensity of peak for sulfone S=O vibration at 1322 cm-1;it was related to O=S=O bound of polysulfone in the sample. The single concentration variable has low outcome, however the mixture concentration interaction was effectively to lead better selectivity of CO2 over N2. In terms of interaction between mixture concentrations, interaction between PSF and N-Methyl-2-pyrrolidone (NMP) has considerable effect on the permeability of CO2 with the highest F value of 0.46 membrane. NMP exhibited a high degree of polarity and hydrogen bonding which led to effect of selective skin and permeation rate. The model regression equations were developed as the potential use for screening the permeability of CO2 and N2 based on the deviation effect of polymer concentration. 展开更多
关键词 mixed-matrix Membranes CO2/N2 SEPARATION POLYMER
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一种快速的二维高分辨波达方向估计方法——混合波达方向矩阵法 被引量:14
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作者 叶中付 沈凤麟 《电子科学学刊》 CSCD 1996年第6期567-573,共7页
本文利用两个具有位移特性的二维传感器子阵列信息构成一种新的矩阵——混合波达方向矩阵。混合波达方向矩阵的特征值和特征矢量分别为信号源方位角与高低角的混合方向元素和方位角与高低角的混合方向矢量。合理选择子阵列构造可以解决... 本文利用两个具有位移特性的二维传感器子阵列信息构成一种新的矩阵——混合波达方向矩阵。混合波达方向矩阵的特征值和特征矢量分别为信号源方位角与高低角的混合方向元素和方位角与高低角的混合方向矢量。合理选择子阵列构造可以解决兼并信号源分辨问题和降低阵列孔径损失。 展开更多
关键词 阵列信号处理 波达方向估计 矩阵
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混合基质水处理膜:材料、制备与性能 被引量:12
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作者 董航 张林 +1 位作者 陈欢林 高从堦 《化学进展》 SCIE CAS CSCD 北大核心 2014年第12期2007-2018,共12页
以反渗透、纳滤为代表的膜技术已广泛应用于海水和苦咸水脱盐等水处理过程。通过将纳米颗粒添加到传统复合膜基质中,可以制备具有高分离性能和耐污染性的新型膜材料。混合基质膜结合了无机材料及有机聚合物各自的优点,是新型水处理膜材... 以反渗透、纳滤为代表的膜技术已广泛应用于海水和苦咸水脱盐等水处理过程。通过将纳米颗粒添加到传统复合膜基质中,可以制备具有高分离性能和耐污染性的新型膜材料。混合基质膜结合了无机材料及有机聚合物各自的优点,是新型水处理膜材料的发展方向。本文综述了添加无机纳米颗粒的混合基质反渗透、纳滤及正渗透膜的研究进展,详细讨论了不同类型纳米材料的性质和功能,分析了表面有机改性对改善纳米材料分散性以及与聚合物基质相容性的作用,探讨了纳米材料添加方式和膜制备方法对膜结构和性能的影响。在此基础上,进一步探究了混合基质膜的成膜及分离机理,归纳了目前研究中存在的主要问题,并对未来水处理膜材料的研发方向提出了建议。 展开更多
关键词 反渗透 纳滤 正渗透 混合基质膜 水处理
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聚乙烯醇/SAPO-34混合基质膜制备及渗透汽化性能综合实验教学设计
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作者 蔡卫滨 宋美洁 +2 位作者 焦健 张琪 马靖文 《实验技术与管理》 CAS 北大核心 2024年第8期195-200,共6页
针对共沸体系的分离,设计了聚乙烯醇/SAPO-34混合基质膜制备及脱水本科生研究性实验。以聚乙烯醇(PVA)为膜材料、以SAPO-34分子筛为填充材料制备了PVA/SAPO-34混合基质膜,利用SEM、FT-IR和接触角分析等手段对膜的物化特性进行了表征;采... 针对共沸体系的分离,设计了聚乙烯醇/SAPO-34混合基质膜制备及脱水本科生研究性实验。以聚乙烯醇(PVA)为膜材料、以SAPO-34分子筛为填充材料制备了PVA/SAPO-34混合基质膜,利用SEM、FT-IR和接触角分析等手段对膜的物化特性进行了表征;采用乙醇/水体系,测试了混合基质膜的渗透汽化分离性能。实践结果表明,该实验有助于学生了解化工分离技术的研究前沿,激发科研热情与兴趣,培养创新精神,促进综合实践能力提升。 展开更多
关键词 渗透汽化 聚乙烯醇 SAPO-34分子筛 混合基质膜 教学实验
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水稳定功能化Cu-BTC基混合基质膜的制备及其CO_(2)分离应用
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作者 郭翔宇 李森 《天津工业大学学报》 CAS 北大核心 2024年第1期10-16,共7页
为提高混合基质膜(mixed-matrix membranes,MMMs)对真实烟道气和含水天然气的分离性能,通过柠檬酸(citric acid,CA)功能化制备了具有高水稳定性的CA-Cu-BTC填料,并将其与Pebax 1657聚合物共混制备了系列不同掺杂量的MMMs,考察了25℃饱... 为提高混合基质膜(mixed-matrix membranes,MMMs)对真实烟道气和含水天然气的分离性能,通过柠檬酸(citric acid,CA)功能化制备了具有高水稳定性的CA-Cu-BTC填料,并将其与Pebax 1657聚合物共混制备了系列不同掺杂量的MMMs,考察了25℃饱和水蒸气下所制备CA-Cu-BTC/Pebax膜的CO_(2)/N_(2)分离性能。结果表明:与纯Pebax膜相比,制备的MMMs具有更好的CO_(2)渗透性和CO_(2)/N_(2)选择性,在CO_(2)渗透通量为837.2 GPU(1 GPU=3.35×10^(-4)μmol/(m^(2)·s·MPa))时,CO_(2)/N_(2)选择性为49.1。此外,CA功能化改性赋予填料的高水稳定性,使得本文制备的MMMs具备了应用于实际工业气体分离的潜力。 展开更多
关键词 金属-有机骨架 水稳定性 混合基质膜 气体分离
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改性Cu-BTC基混合基质膜在CO_(2)分离中的应用
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作者 王涛 高翔 +5 位作者 高继峰 邓海全 余显涌 周振华 唐玲 吕航 《化工进展》 EI CAS CSCD 北大核心 2024年第6期3240-3246,共7页
金属-有机骨架材料(metal-organic frameworks,MOFs)作为一种有潜力的分离材料,其孔道结构独特,具有高度可调性和选择性,在膜分离领域具有广阔的应用前景。然而,MOFs在潮湿的环境下易损坏,这严重限制了其在膜分离领域的应用。因此,提高M... 金属-有机骨架材料(metal-organic frameworks,MOFs)作为一种有潜力的分离材料,其孔道结构独特,具有高度可调性和选择性,在膜分离领域具有广阔的应用前景。然而,MOFs在潮湿的环境下易损坏,这严重限制了其在膜分离领域的应用。因此,提高MOFs的水稳定性,是实现其在膜分离领域应用的重要问题之一。本文通过柠檬酸铵(ammonium citrate,AC)功能化制备了具有高水稳定性的Cu-BTC-AC填料,并将其与Pebax 1657聚合物共混制备了系列不同掺杂量的MMMs,并考察了25℃饱和水蒸气下所制备Cu-BTC-AC/Pebax膜的CO_(2)/N_(2)分离性能。与纯Pebax膜相比,本工作中制备的MMMs具有更优异的CO_(2)渗透性和CO_(2)/N_(2)选择性,在CO_(2)渗透通量为776.5GPU时CO_(2)/N_(2)选择性为46.7。此外,AC功能化改性赋予填料的高水稳定性使得本工作中制备的MMMs具备了应用于实际工业气体分离的潜力。 展开更多
关键词 金属有机骨架 柠檬酸铵 水稳定性 混合基质膜 气体分离
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CO_(2)捕集膜分离的Pebax基材料研究进展
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作者 何文 王波 +3 位作者 冯晗俊 孔祥如 李桃 肖睿 《化学学报》 SCIE CAS CSCD 北大核心 2024年第2期226-241,共16页
膜分离CO_(2)技术是实现“双碳”目标的关键技术手段之一,而膜材料的性能对膜分离效果具有重要影响.聚醚嵌段聚酰胺(Pebax)对CO_(2)具有较高的渗透性和选择性,其自身具有高机械强度和良好的化学稳定性,且价廉易得,是一种极具潜力的聚合... 膜分离CO_(2)技术是实现“双碳”目标的关键技术手段之一,而膜材料的性能对膜分离效果具有重要影响.聚醚嵌段聚酰胺(Pebax)对CO_(2)具有较高的渗透性和选择性,其自身具有高机械强度和良好的化学稳定性,且价廉易得,是一种极具潜力的聚合物气体分离膜材料.本综述介绍了用于CO_(2)捕集的Pebax基膜材料的特征及其气体分离性能的影响因素,重点概述了Pebax制备工艺优化、促进传递膜、交联和共混四种Pebax超薄复合膜的优化方式,并综述了Pebax基混合基质膜及填料功能化的研究进展.针对目前Pebax基材料存在渗透性和选择性权衡的问题,对Pebax基膜材料未来的优化方向作出了展望. 展开更多
关键词 Pebax 膜分离 CO_(2)捕集 薄膜制备 混合基质膜
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固态溶剂法制备超薄混合基质膜用于分子筛分 被引量:1
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作者 高从堦 《华东理工大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第6期773-776,共4页
分离过程在化工生产、国民经济和国防建设等方面具有重要意义,膜分离技术因高效、节能和环境友好的特点扮演着重要角色。混合基质膜结合了分子筛材料的高渗透分离性能和聚合物膜的良好加工性,近年来成为研究热点。本文主要介绍了混合基... 分离过程在化工生产、国民经济和国防建设等方面具有重要意义,膜分离技术因高效、节能和环境友好的特点扮演着重要角色。混合基质膜结合了分子筛材料的高渗透分离性能和聚合物膜的良好加工性,近年来成为研究热点。本文主要介绍了混合基质膜的发展以及突破性工作。随着填料类型的丰富,混合基质膜在多种分离场景中表现良好。最近,南京工业大学膜研究团队提出了“固态溶剂法”制备混合基质膜,膜厚可控制在100 nm以下、掺杂量提高了2~4倍,实现了膜渗透性和选择性数量级的提升。该方法构建了一种以填料为主、聚合物为辅的新型混合基质膜结构,在保留良好加工性和放大制备前景的同时,将混合基质膜分离性能推向了类无机分子筛膜的新高度。 展开更多
关键词 混合基质膜 固态溶剂法 聚合物膜 分子筛 分离性能
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三类保辛摄动及其数值比较 被引量:3
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作者 钟万勰 孙雁 《动力学与控制学报》 2005年第2期1-9,共9页
摄动法近似应当保辛.本文指出,有限元位移法自动保辛,有限元混合能表示也保辛.摄动法的刚度阵Taylor级数展开能证明保辛;混合能的Taylor级数展开摄动也证明了保辛.但传递辛矩阵的Taylor级数展开摄动却不能保辛.辛矩阵只能在乘法群下保辛... 摄动法近似应当保辛.本文指出,有限元位移法自动保辛,有限元混合能表示也保辛.摄动法的刚度阵Taylor级数展开能证明保辛;混合能的Taylor级数展开摄动也证明了保辛.但传递辛矩阵的Taylor级数展开摄动却不能保辛.辛矩阵只能在乘法群下保辛,故传递辛矩阵的保辛摄动必须采用正则变换的乘法.虽然刚度阵加法摄动、混合能矩阵加法摄动与传递辛矩阵正则变换乘法摄动都保辛,但这3种摄动近似并不相同.最后通过数值例题给出了对比. 展开更多
关键词 Taylor级数展开 数值比较 正则变换 辛矩阵 混合能 矩阵加法 摄动法 有限元 刚度阵 位移法 乘法群 传递 近似 证明
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标准混合差集矩阵的构造 被引量:4
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作者 庞善起 张应山 《系统科学与数学》 CSCD 北大核心 2010年第3期410-416,共7页
通过利用差集矩阵和投影矩阵的正交分解之间的关系,首先提出了构造小的标准混合差集矩阵的一般方法.其次,给定一个阶为r+1的标准混合差集矩阵和一个阶为r的差集矩阵,首先提出了构造阶为r(r+1)的标准混合差集矩阵的一般方法.如果阶为r的... 通过利用差集矩阵和投影矩阵的正交分解之间的关系,首先提出了构造小的标准混合差集矩阵的一般方法.其次,给定一个阶为r+1的标准混合差集矩阵和一个阶为r的差集矩阵,首先提出了构造阶为r(r+1)的标准混合差集矩阵的一般方法.如果阶为r的差集矩阵不存在但一个试验次数为r^2的正交表存在,也可以通过它们构造阶数较大的标准混合差集矩阵. 展开更多
关键词 标准混合差集矩阵 Kronecker和 正交表 投影矩阵
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生物炭作为无土栽培基质的初步探究 被引量:4
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作者 陈慧玲 林向阳 +5 位作者 罗登来 林圣楠 朱丰 黄金城 刘明华 阮榕生 《福州大学学报(自然科学版)》 CAS 北大核心 2017年第2期280-284,共5页
研究柠条深度裂解产生的生物炭作为无土栽培机制的可行性,以探讨柠条的综合开发和利用.试验分析了生物炭和草炭复配基质的理化特性,并对小白菜做育苗期盆栽试验.结果表明:当草炭和柠条炭的质量比为4∶2时达到最佳配比,此时混配基质各项... 研究柠条深度裂解产生的生物炭作为无土栽培机制的可行性,以探讨柠条的综合开发和利用.试验分析了生物炭和草炭复配基质的理化特性,并对小白菜做育苗期盆栽试验.结果表明:当草炭和柠条炭的质量比为4∶2时达到最佳配比,此时混配基质各项指标均符合理想基质的要求;柠条炭具有强大的吸附能力和丰富的孔隙结构,其作为草炭的混配基质能够较大程度提高基质的透气性和速效钾含量,有贮存和缓释养分的作用. 展开更多
关键词 生物炭 混配基质 无土栽培 理化特性 柠条
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