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Recent advances in multi-layer composite polymeric membranes for CO_2 separation: A review 被引量:11
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作者 Zhongde Dai Luca Ansaloni Liyuan Deng 《Green Energy & Environment》 SCIE 2016年第2期102-128,共27页
The development of multilayer composite membranes for CO_2 separation has gained increasing attention due to the desire for energy efficient technologies. Multilayer composite membranes have many advantages, including... The development of multilayer composite membranes for CO_2 separation has gained increasing attention due to the desire for energy efficient technologies. Multilayer composite membranes have many advantages, including the possibility to optimize membrane materials independently by layers according to their different functions and to reduce the overall transport resistance by using ultrathin selective layers, and less limitations on the material mechanical properties and processability. A comprehensive review is required to capture details of the progresses that have already been achieved in developing multilayer composite membranes with improved CO_2 separation performance in the past 15-20 years.In this review, various composite membrane preparation methods were compared, advances in composite membranes for CO_2/CH_4 separation,CO_2/N_2 and CO_2/H_2 separation were summarized with detailed data, and challenges facing for the CO_2 separation using composite membranes,such as aging, plasticization and long-term stability, were discussed. Finally the perspectives and future research directions for composite membranes were presented. 展开更多
关键词 Composite membrane CO2 separation Membrane fabrication Membrane aging Long-term stability
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Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components 被引量:1
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作者 Haibin Liu Run Hou +2 位作者 Chenghao Wu Ruishan Xie Shujun Chen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期425-438,共14页
At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass components.In this study,multi-laye... At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass components.In this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool head.The material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum alloys.The results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center area.Repeated friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped zone.The tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition sample.It is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping area.The multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components. 展开更多
关键词 aluminum alloy additive manufacturing SOLID-STATE friction stir welding multi-layer multi-pass
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Flotation separation of chalcopyrite from pyrite using mineral fulvic acid as selective depressant under weakly alkaline conditions 被引量:3
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作者 Zhi-hao SHEN Shu-ming WEN +1 位作者 Jia-mei HAO Qi-cheng FENG 《Transactions of Nonferrous Metals Society of China》 2025年第1期313-325,共13页
Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger in... Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite. 展开更多
关键词 mineral fulvic acid CHALCOPYRITE PYRITE flotation separation
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Recent advances in the modification of melamine sponge for oil-water separation 被引量:2
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作者 Xing Zhou Dexiang Li +5 位作者 Lili Wang Qi Wang Zhen Wang Qing Jing Rinderer Marisol Lu Li 《Journal of Materials Science & Technology》 2025年第4期209-224,共16页
Melamine sponge is a major concern for oil-water separation due to its lightweight,high porosity(>99%),cost-effectiveness,impressive mechanical properties,and chemical/thermal stability.However,its amphiphilic natu... Melamine sponge is a major concern for oil-water separation due to its lightweight,high porosity(>99%),cost-effectiveness,impressive mechanical properties,and chemical/thermal stability.However,its amphiphilic nature hinders selective oil absorption in water.Recent strategies to enhance hydrophobicity are reviewed,including synthetic methods and materials,with comprehensive explanations of the mechanisms driven by surface energy and roughness.Key performance indicators for MS in oil-water separation,including adsorption capacity,wettability,stability,emulsion separation,reversible wettability switching,flame retardancy,mechanical properties,and recyclability,are thoroughly discussed.In conclusion,this review provides insights into the future potential and direction of functional melamine sponges in oil-water separation. 展开更多
关键词 Melamine sponge HYDROPHOBICITY LIPOPHILICITY Oil-water separation MODIFICATION
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Comprehensive recovery of rare earth elements and gypsum from phosphogypsum:A wastewater free process combining gravity separation and hydrometallurgy 被引量:1
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作者 Jialin Qing Dapeng Zhao +6 位作者 Li Zeng Guiqing Zhang Liang Zhou Jiawei Du Qinggang Li Zuoying Cao Shengxi Wu 《Journal of Rare Earths》 2025年第2期362-370,I0005,共10页
Comprehensive utilization of phosphogypsum(PG)has attracted much attention,especially for the recovery of rare earth elements(REEs)and gypsum due to the issues of stockpile,environmental pollution,and waste of associa... Comprehensive utilization of phosphogypsum(PG)has attracted much attention,especially for the recovery of rare earth elements(REEs)and gypsum due to the issues of stockpile,environmental pollution,and waste of associated resources.Traditional utilization methods suffered the issues of low REEs leaching efficiency,huge amount of CaSO_(4)saturated wastewater and high recovery cost.To solve these issues,this study investigated the occurrence of REEs in PG and the leaching of REEs.The results show that REEs in PG are in the forms of(1)REEs mineral inclusions,(2)REEs isomorphous substitution of Ca^(2+)in gypsum lattice,(3)dispersed soluble REEs salts.Acid leaching results demonstrate that(1)the dissolution of gypsum matrix is the control factor of REEs leaching;(2)H_(2)SO_(4)is a promising leachant considering the recycle of leachate;(3)the gypsum matrix suffers a recrystallization during the acid leaching and releases the soluble REEs from PG to aqueous solution.For the recovery of the undissolved REEs mineral inclusions,wet sieving concentrated 37.1 wt%of the REEs in a 10.7 wt%mass,increasing REEs content from 309 to 1071 ppm.Finally,a green process combining gravity separation and hydrometallurgy is proposed.This process owns the merits of wastewater free,considerable REEs recovery(about 10%increase compared with traditional processes),excellent gypsum purification(>95 wt%CaSO_(4)·2H_(2)O,with<0.06 wt%of soluble P_(2)O_(5) and<0.015 wt%of soluble F)and reagent saving(about 2/3less reagent consumption than non-cyclical leaching). 展开更多
关键词 PHOSPHOGYPSUM Rare earths Wastewater free Recrystallization reinforcement Gravity separation
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Enhancing Piezoelectric Output via Constrained Phase Separation on Single Nanofibers:Harnessing Endogenous Triboelectricity 被引量:1
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作者 YU Dingming LIU Lifang +2 位作者 YU Jianyong SI Yang DING Bin 《Journal of Donghua University(English Edition)》 2025年第1期12-19,共8页
The research,fabrication and development of piezoelectric nanofibrous materials offer effective solutions to the challenges related to energy consumption and non-renewable resources.However,enhancing their electrical ... The research,fabrication and development of piezoelectric nanofibrous materials offer effective solutions to the challenges related to energy consumption and non-renewable resources.However,enhancing their electrical output still remains a significant challenge.Here,a strategy of inducing constrained phase separation on single nanofibers via shear force was proposed.Employing electrospinning technology,a polyacrylonitrile/polyvinylidene difluoride(PAN/PVDF)nanofibrous membrane was fabricated in one step,which enabled simultaneous piezoelectric and triboelectric conversion within a single-layer membrane.Each nanofiber contained independent components of PAN and PVDF and exhibited a rough surface.The abundant frictional contact points formed between these heterogeneous components contributed to an enhanced endogenous triboelectric output,showcasing an excellent synergistic effect of piezoelectric and triboelectric response in the nanofibrous membrane.Additionally,the component mass ratio influenced the microstructure,piezoelectric conformation and piezoelectric performance of the PAN/PVDF nanofibrous membranes.Through comprehensive performance comparison,the optimal mass ratio of PAN to PVDF was determined to be 9∶1.The piezoelectric devices made of the optimal PAN/PVDF nanofibrous membranes with rough nanofiber surfaces generated an output voltage of 20 V,which was about 1.8 times that of the smooth one at the same component mass ratio.The strategy of constrained phase separation on the surface of individual nanofibers provides a new approach to enhance the output performance of single-layer piezoelectric nanofibrous materials. 展开更多
关键词 nanofibrous membrane constrained phase separation endogenous triboelectric effect dual-component piezoelectric property
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Organic solvent nanofiltration membranes for separation in non-polar solvent system 被引量:1
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作者 Shuyun Gu Siyao Li Zhi Xu 《Green Energy & Environment》 2025年第2期244-267,共24页
Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltr... Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltration represents an advanced membrane separation technology capable of discerning molecules within a molecular weight range of approximately 100-1000 Da in organic solvents,offering low energy requirements and minimal carbon footprints.Molecular separation in non-polar solvent system,such as toluene,n-hexane,and n-heptane,has gained paramount importance due to their extensive use in the pharmaceutical,biochemical,and petrochemical industries.In this review,we presented recent advancements in membrane materials,membrane fabrication techniques and their promising applications for separation in nonpolar solvent system,encompassing hydrocarbon separation,bioactive molecule purification and organic solvent recovery.Furthermore,this review highlighted the challenges and opportunities associated with membrane scale-up strategies and the direct translation of this promising technology into industrial applications. 展开更多
关键词 Organic solvent nanofiltration Membranes Membrane separation Non-polar solvent system Petrochemical and pharmaceutical application
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Facile Preparation of Robust Superhydrophobic Stainless Steel Mesh Coated with Urushiol-based Polybenzoxazine and SiO_(2) for Efficient Oil/water Separation 被引量:1
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作者 ZHU Yongfei LI Yuxuan +2 位作者 XIAO Jianrui LI Jiayi YU Shujuan 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期842-851,共10页
Separating oil/water mixtures via superhydrophobic stainless steel mesh(SSM)is a kind of efficient methods of treating oily wastewater,and the superhydrophobic SSM with a low cost,simple fabrication process and robust... Separating oil/water mixtures via superhydrophobic stainless steel mesh(SSM)is a kind of efficient methods of treating oily wastewater,and the superhydrophobic SSM with a low cost,simple fabrication process and robust usability remains a challenge.Herein,urushiol-based benzoxazine(U-D)with a strong substrate adhesion and low surface free energy was used to anchor SiO_(2) particles on the SSM surface to obtain a durable superhydrophobic SSM(PU-D/SiO_(2)/SSM)through a simple dip-coating process,meanwhile,epoxy resin was also introduced to further improve the adhesion between coating and SSM.PU-D/SiO_(2)/SSM could successfully separate various immiscible oil-water mixtures with a separation efficiency of over 96%and a flux up to 27100 L/m^(2) h only by gravity,respectively.Especially,the modified SSM could effectively remove water from water-in-oil emulsion with a separation efficiency of 99.7%.Moreover,PU-D/SiO_(2)/SSM had an outstanding reusability,whose water contact angle and separation efficiency only slightly decreased after 20 cycles of separating oil/water mixture.In addition,the modified SSM also displayed a satisfactory abrasion resistance,chemical stability and self-cleaning property.Thereby,the robust PU-D/SiO_(2)/SSM prepared by cheap raw materials and facile dip-coating method exhibits a high potential for separating oil/water mixtures. 展开更多
关键词 oil/water separation SUPERHYDROPHOBIC urushiol-based benzoxazine stainless steel mesh SiO_(2)
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Deep eutectic solvents for separation and purification applications in critical metal metallurgy:Recent advances and perspectives
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作者 Shuo Chen Shengpeng Su +4 位作者 Yanfang Huang Bingbing Liu Hu Sun Shuzhen Yang Guihong Han 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期1-19,共19页
Solvent extraction,a separation and purification technology,is crucial in critical metal metallurgy.Organic solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and ... Solvent extraction,a separation and purification technology,is crucial in critical metal metallurgy.Organic solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental safety.Neoteric solvents have been recognized as potential alternatives to these harmful organic solvents.In the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low cost.In this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically described.Subsequently,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively summarized.Finally,future opportunities and challenges of DESs were explored in the current research area.In conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy. 展开更多
关键词 deep eutectic solvents preparations PROPERTIES separation and purification critical metal metallurgy
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A propane‑selective metal‑organic framework for inverse selective adsorption propane/propylene separation
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作者 YANG Shanqing WANG Lulu +3 位作者 ZHANG Qiang LI Jiajia LI Yilong HU Tongliang 《无机化学学报》 北大核心 2025年第10期2138-2148,共11页
We report a robust pillar-layered metal-organic framework,Zn‑tfbdc‑dabco(tfbdc:tetrafluoroterephthal-ate,dabco:1,4-diazabicyclo[2.2.2]octane),featuring the fluorinated pore environment,for the preferential binding of ... We report a robust pillar-layered metal-organic framework,Zn‑tfbdc‑dabco(tfbdc:tetrafluoroterephthal-ate,dabco:1,4-diazabicyclo[2.2.2]octane),featuring the fluorinated pore environment,for the preferential binding of propane over propylene and thus highly inverse selective separation of propane/propylene mixture.The inverse propane-selective performance of Zn‑tfbdc‑dabco for the propane/propylene separation was validated by single-component gas adsorption isotherms,isosteric enthalpy of adsorption calculations,ideal adsorbed solution theory calculations,along with the breakthrough experiment.The customized fluorinated networks served as a propane-trap to form more interactions with the exposed hydrogen atoms of propane,as unveiled by the simulation studies at the molecular level.With the advantage of inverse propane-selective adsorption behavior,high adsorption capacity,good cycling stability,and low isosteric enthalpy of adsorption,Zn‑tfbdc‑dabco can be a promising candidate adsorbent for the challenging propane/propylene separation to realize one-step purification of the target propylene substance. 展开更多
关键词 metal-organic framework propane/propylene separation inverse selective adsorption separation
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Constructing ether-rich and carboxylate hydrogen bonding sites in protic ionic liquids for efficient and simultaneous membrane separation of H_(2)S and CO_(2) from CH_(4) 被引量:1
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作者 Ping Zhang Xingyun Ma +3 位作者 Zhuoheng Tu Xiaomin Zhang Xingbang Hu Youting Wu 《Green Energy & Environment》 2025年第3期560-572,共13页
Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-... Removing H_(2)S and CO_(2)is of great significance for natural gas purification.With excellent gas affinity and tunable structure,ionic liquids(ILs) have been regarded as nontrivial candidates for fabricating polymer-based membranes.Herein,we firstly reported the incorporation of protic ILs (PILs) having ether-rich and carboxylate sites (ECPILs) into poly(ether-block-amide)(Pebax) matrix for efficient separation H_(2)S and CO_(2)from CH_(4).Notably,the optimal permeability of H_(2)S reaches up to 4310 Barrer (40C,0.50 bar) in Pebax/ECPIL membranes,along with H_(2)S/CH_(4)and (H_(2)StCO_(2))/CH_(4)selectivity of 97.7 and 112.3,respectively.These values are increased by 1125%,160.8%and 145.9%compared to those in neat Pebax membrane.Additionally,the solubility and diffusion coefficients of the gases were measured,demonstrating that ECPIL can simultaneously strengthen the dissolution and diffusion of H_(2)S and CO_(2),thus elevating the permeability and permselectivity.By using quantum chemical calculations and FT-IR spectroscopy,the highly reversible multi-site hydrogen bonding interaction between ECPILs and H_(2)S was revealed,which is responsible for the fast permeation of H_(2)S and good selectivity.Furthermore,H_(2)S/CO_(2)/CH_(4)(3/3/94 mol/mol) ternary mixed gas can be efficiently and stably separated by Pebax/ECPIL membrane for at least 100 h.Overall,this work not only illustrates that PILs with ether-rich and carboxylate hydrogen bonding sites are outstanding materials for simultaneous removal of H_(2)S and CO_(2),but may also provide a novel insight into the design of membrane materials for natural gas upgrading. 展开更多
关键词 H_(2)S Protic ionic liquid Multi-site hydrogen bonding interaction Membrane separation Natural gas purification
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Merging polymers of intrinsic microporosity and porous carbon-based zinc oxide composites in novel mixed matrix membranes for efficient gas separation
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作者 Muning Chen Jiemei Zhou +7 位作者 Jing Ma Weigang Zheng Guanying Dong Xin Li Zhihong Tian Yatao Zhang Jing Wang Yong Wang 《Green Energy & Environment》 SCIE EI CAS 2025年第1期203-213,共11页
Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a sim... Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of polymers.However,achieving a simultaneous enhancement of permeability and selectivity remains a formidable challenge,due to the difficulty of achieving an optimal match between polymers and fillers.In this study,we incorporate a porous carbon-based zinc oxide composite(C@ZnO)into high-permeability polymers of intrinsic microporosity(PIMs)to fabricate MMMs.The dipole–dipole interaction between C@ZnO and PIMs ensures their exceptional compatibility,mitigating the formation of non-selective voids in the resulting MMMs.Concurrently,C@ZnO with abundant interconnected pores can provide additional low-resistance pathways for gas transport in MMMs.As a result,the CO_(2) permeability of the optimized C@ZnO/PIM-1 MMMs is elevated to 13,215 barrer,while the CO_(2)/N_(2) and CO_(2)/CH_(4) selectivity reached 21.5 and 14.4,respectively,substantially surpassing the 2008 Robeson upper bound.Additionally,molecular simulation results further corroborate that the augmented membrane gas selectivity is attributed to the superior CO_(2) affinity of C@ZnO.In summary,we believe that this work not only expands the application of MMMs for gas separation but also heralds a paradigm shift in the application of porous carbon materials. 展开更多
关键词 Mixed matrix membranes Polymers of intrinsic microporosity CO_(2)separation Porous carbon materials
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Recent advances in chiral drug separation membranes:design,mechanisms,challenges,and prospects
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作者 Jianyu WANG Qindan CHU +2 位作者 Chuanjie FANG Baoku ZHU Liping ZHU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第4期285-304,共20页
The presence of chirality,a fundamental attribute found in nature,is of great significance in the field of pharmaceutical science.Chiral drugs are unique in that their molecular structure is non-superimposable on its ... The presence of chirality,a fundamental attribute found in nature,is of great significance in the field of pharmaceutical science.Chiral drugs are unique in that their molecular structure is non-superimposable on its mirror image.This stereoisomerism significantly impacts the functionality,metabolic pathway,effectiveness,and safety of chiral medications.The enantiomers of chiral drugs can exhibit diverse pharmacological effects in the human body.As a result,it is essential to separate and purify chiral drugs effectively.Despite the abundance of reports on chiral drug separation membranes,there is a dearth of comprehensive reviews.This paper aims to fill this gap by providing a thorough review from a materials perspective,with a focus on the design and construction of chiral drug separation membranes.Furthermore,it systematically analyzes the separation mechanisms employed by these membranes.The paper also delves into the challenges and prospects related to chiral drug separation membranes,with the intention of imparting valuable insights for further research and development in this field. 展开更多
关键词 Chiral drugs Chiral separation separation mechanisms Membrane separation
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Experimental research on enhanced the microfine oil droplets separation using hydrocyclone coupled with fiber coalescence
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作者 Lian Zhang Zhaojin Lu +1 位作者 Likun Ma Zhishan Bai 《Chinese Journal of Chemical Engineering》 2025年第6期15-24,共10页
The limitations of swirl separation in removing microfine oil droplets in water have driven the development of hydrocyclone technology coupled with multiphase or multifield techniques.To enhance microfine oil droplets... The limitations of swirl separation in removing microfine oil droplets in water have driven the development of hydrocyclone technology coupled with multiphase or multifield techniques.To enhance microfine oil droplets separation,a novel hydrocyclone separation coupled with fiber coalescence(HCCFC) was designed.The interaction between fiber balls and oil droplets inside the hydrocyclone,including droplet coalescence and breakage,was investigated.The influence of different operating parameters on separation efficiency was discussed.The results showed that fiber balls promoted oil droplet coalescence when the inlet droplet size(D_(43)) was below 22.37 μm but caused droplet breakage above this threshold.The coalescence performance of HCCFC improved with increasing inlet oil content but declined beyond 450 mg·L^(-1).Separation experiments confirmed that HCCFC outperformed conventional hydrocyclone,with separation efficiency increasing by 2.9% to 20.0%.As the fiber ball content and inlet flow rate increased,the separation efficiency showed a trend of first increasing and then decreasing.Additionally,HCCFC's separation efficiency varied with inlet oil droplet size distribution,showing the most significant enhancement when D_(43) was 22.37 μm,where separation efficiency increased by 14.4%.These findings offer insights into the development and application of multiphase coupled with hydrocyclone technology. 展开更多
关键词 Oil–water separation Fiber coalescence HYDROCYCLONE BREAKAGE separation efficiency
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A Multi-Layer Progressive Analysis Method for Collision Energy Flow in Rail Trains
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作者 Jingke Zhang Tao Zhu +4 位作者 Xiaorui Wang Bing Yang Shoune Xiao Guangwu Yang Yuru Li 《Chinese Journal of Mechanical Engineering》 2025年第5期425-439,共15页
The huge impact kinetic energy cannot be quickly dissipated by the energy-absorbing structure and transferred to the other vehicle through the car body structure,which will cause structural damage and threaten the liv... The huge impact kinetic energy cannot be quickly dissipated by the energy-absorbing structure and transferred to the other vehicle through the car body structure,which will cause structural damage and threaten the lives of the occupants.Therefore,it is necessary to understand the laws of energy conversion,dissipation and transfer during train collisions.This study proposes a multi-layer progressive analysis method of energy flow during train collisions,considering the characteristics of the train.In this method,the train collision system is divided into conversion,dissipation,and transfer layers from the perspective of the train,collision interface,and car body structure to analyze the energy conversion,dissipation and transfer characteristics.Taking the collision process of a rail train as an example,a train collision energy transfer path analysis model was established based on power flow theory.The results show that when the maximum mean acceleration of the vehicle meets the standard requirements,the jerk may exceed the allowable limit of the human body,and there is a risk of injury to the occupants of a secondary collision.The decay rate of the collision energy along the direction of train operation reaches 79%.As the collision progresses,the collision energy gradually converges in the structure with holes,and the structure deforms when the gathered energy is greater than the maximum energy the structure can withstand.The proposed method helps to understand the train collision energy flow law and provides theoretical support for the train crashworthiness design in the future. 展开更多
关键词 Train Cllision multi-layer Progression Energy Flow Energy Conversion Energy Dissipation Energy Transfer
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Highly efficient separation of high-valent actinide ions from lanthanides via fractional crystallization
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作者 Yarui Li Huangjie Lu +3 位作者 Yingzhe Du Jie Qiu Peng Lin Jian Lin 《Chinese Journal of Structural Chemistry》 2025年第4期64-68,共5页
Partitioning of actinides from lanthanides is pivotal for advancing nuclear waste management and sustaining nuclear energy development,yet it remains a formidable challenge due to the intricate chemical behaviors of t... Partitioning of actinides from lanthanides is pivotal for advancing nuclear waste management and sustaining nuclear energy development,yet it remains a formidable challenge due to the intricate chemical behaviors of these f-block elements.In this study,we introduce 3,6-di-2-pyridyl-1,2,4,5-tetrazine(L1),whose hydrolysis product of pyridine-2-carbox-aldehyde(pyridine-2-carbonyl)-hydrazone(L2)can fractionally crystallize U(Ⅵ)ions over Ln(Ⅲ)cations with high selectivity and efficiency.Through hydrolysis-induced C–N bond cleavage,L2 acts as a tetradentate ligand,coordinating with two UO_(2)^(2+) ions in a planar arrangement to form a zerodimensional cluster,[(UO_(2))2(μ_(3)-O)(L2)(CH_(3)COO)]·DMF(U-L2),while lanthanide ions(Ln=La,Pr,Nd,Sm,Eu,Gd,Tb,Yb,and Lu)remain in solution due to their inability to achieve similar coordination.This selective crystallization strategy yields exceptional separation factors(SFs)between U(Ⅵ)and Ln(Ⅲ),with a value of 756276 between U(Ⅵ)and Sm(Ⅲ),the highest reported to date.Furthermore,this fractional crystallization separation process can be achieved under mild ambient conditions with high SFs,enabling the development of a rapid,safe and energy-efficient strategy for once-through separation of high oxidation state actinides from lanthanides. 展开更多
关键词 LANTHANIDE Actinide URANIUM separation CRYSTALLIZATION
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Intrusion Detection Model on Network Data with Deep Adaptive Multi-Layer Attention Network(DAMLAN)
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作者 Fatma S.Alrayes Syed Umar Amin +2 位作者 Nada Ali Hakami Mohammed K.Alzaylaee Tariq Kashmeery 《Computer Modeling in Engineering & Sciences》 2025年第7期581-614,共34页
The growing incidence of cyberattacks necessitates a robust and effective Intrusion Detection Systems(IDS)for enhanced network security.While conventional IDSs can be unsuitable for detecting different and emerging at... The growing incidence of cyberattacks necessitates a robust and effective Intrusion Detection Systems(IDS)for enhanced network security.While conventional IDSs can be unsuitable for detecting different and emerging attacks,there is a demand for better techniques to improve detection reliability.This study introduces a new method,the Deep Adaptive Multi-Layer Attention Network(DAMLAN),to boost the result of intrusion detection on network data.Due to its multi-scale attention mechanisms and graph features,DAMLAN aims to address both known and unknown intrusions.The real-world NSL-KDD dataset,a popular choice among IDS researchers,is used to assess the proposed model.There are 67,343 normal samples and 58,630 intrusion attacks in the training set,12,833 normal samples,and 9711 intrusion attacks in the test set.Thus,the proposed DAMLAN method is more effective than the standard models due to the consideration of patterns by the attention layers.The experimental performance of the proposed model demonstrates that it achieves 99.26%training accuracy and 90.68%testing accuracy,with precision reaching 98.54%on the training set and 96.64%on the testing set.The recall and F1 scores again support the model with training set values of 99.90%and 99.21%and testing set values of 86.65%and 91.37%.These results provide a strong basis for the claims made regarding the model’s potential to identify intrusion attacks and affirm its relatively strong overall performance,irrespective of type.Future work would employ more attempts to extend the scalability and applicability of DAMLAN for real-time use in intrusion detection systems. 展开更多
关键词 Intrusion detection deep adaptive networks multi-layer attention DAMLAN network security anomaly detection
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A comprehensive review on Mg-based materials as filler in mixed matrix membranes for CO_(2)separation
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作者 Payam Veisi Alireza Askari Arash Fattah-alhosseini 《Journal of Magnesium and Alloys》 2025年第2期539-561,共23页
The crisis of excessive increase in CO_(2)emissions has quickly become a serious issue and requires low-cost and bio-compatible solutions.The employee of membrane technology for CO_(2)gas separation has garnered signi... The crisis of excessive increase in CO_(2)emissions has quickly become a serious issue and requires low-cost and bio-compatible solutions.The employee of membrane technology for CO_(2)gas separation has garnered significant interest among researchers.However,this method encounters challenges related to selectivity and permeability.Therefore,modifying and reinforcing the polymer membranes to improve gas separation performance seems essential.Among the various methods for polymer membrane modification,modification with magnesium-based fillers to prepare a mixed matrix membrane(MMM)is considered an efficient method.Owing to magnesium metal's low weight,low density,high strength,and good selectivity,magnesium-based materials(Mg-based materials)have more porosity,higher available surface area,more adsorption sites,lighter weight,and more gas absorption tendency than other fillers,which makes them an attractive choice for the preparation of gas separation MMMs.This research deals with the introduction of Mg-based materials,various methods of synthesis of Mg-based materials,different methods of introducing Mg-based materials into the membrane matrix,and their effect on the performance of MMMs in CO_(2)gas separation applications.Therefore,this review can provide researchers with light horizons in using the high potential of Mg-based materials as efficient fillers in MMMs to achieve excellent permeability and selectivity and generally improve their performance in CO_(2)gas separation applications. 展开更多
关键词 Mg-based materials Mg-based fillers Mixed matrix membrane(mmm) Co2 separation Gas separation applications
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Application of Metal-Organic Frameworks (MOFs) in Gas Adsorption and Separation
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作者 Zhiqing Dong 《化学发展前沿(中英文版)》 2025年第1期1-7,共7页
Metal-Organic Frameworks(MOFs)have emerged as promising materials for gas adsorption and separation due to their exceptional surface area,tunable porosity,and versatility in functionalization.This paper explores the m... Metal-Organic Frameworks(MOFs)have emerged as promising materials for gas adsorption and separation due to their exceptional surface area,tunable porosity,and versatility in functionalization.This paper explores the mechanisms of gas adsorption in MOFs,including physical adsorption,chemisorption,and synergistic effects,which contribute to their efficiency in capturing and separating gases.The applications of MOFs in key areas such as carbon dioxide capture,hydrogen storage,natural gas separation,and air purification are discussed,highlighting their potential to address pressing environmental and energy challenges.Additionally,the use of MOFs in selective gas separation,membranes,and adsorption-based technologies like Pressure Swing Adsorption(PSA)and Vacuum Swing Adsorption(VSA)is explored,emphasizing their advantages over traditional materials.Despite challenges related to scalability,stability,and cost,MOFs hold great promise for advancing gas separation technologies in the near future,offering more efficient,sustainable,and environmentally friendly solutions. 展开更多
关键词 Metal-Organic Frameworks Gas Adsorption Gas separation Carbon Dioxide Capture Hydrogen Storage Natural Gas separation Pressure Swing Adsorption
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Perfect separation of pyridine and 3-methylpyridine by cucurbit[6]uril
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作者 Yongqing Zeng Caijun Liang +7 位作者 Xin Lu Lingxue Zhao Fangting Wu Tao Hou Anting Zhao Menglan Lv Zhu Tao Qing Li 《Chinese Chemical Letters》 2025年第9期330-333,共4页
Pyridine(Py) and 3-methylpyridine(3-MP) are crucial intermediates in chemical industrial processes.Here,we provide a simple and energy-efficient approach for the isolation of Py and 3-MP by employing crystalline cucur... Pyridine(Py) and 3-methylpyridine(3-MP) are crucial intermediates in chemical industrial processes.Here,we provide a simple and energy-efficient approach for the isolation of Py and 3-MP by employing crystalline cucurbit[6]uril(Q[6]).The crystal exhibit high selectivity for Py from the mixture of Py and 3-MP in both vapor and liquid phases,with separation purities close to 100%.The selectivity is attributed to the varying stability of the host-vip complexes after the absorption of Py or 3-MP,as revealed by the single-crystal structure analysis.ITC experimental results and DFT calculations indicate that,compared to3-MP,Q[6] has a higher binding strength and lower binding energy with Py.In addition,pyridine can be removed from the Q[6] cavity through vacuum heating or organic solvent immersion,enabling Q[6]reuse via reversible vip loading.This method offers a promising approach for high-purity Py and 3-MP separation with significant economic and environmental benefits. 展开更多
关键词 uril Molecules separation Adsorptive separation Host–vip complexation Supramolecular chemistry
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