Thin-film nanocomposite(TFN) membranes have garnered considerable attention for their potential to improve separation performance by incorporating nanomaterials. However, challenges such as these materials' uneven...Thin-film nanocomposite(TFN) membranes have garnered considerable attention for their potential to improve separation performance by incorporating nanomaterials. However, challenges such as these materials' uneven distribution and aggregation have hindered practical applications. While prior studies have largely concentrated on modifying nanosheets for compatibility with polymer matrices, the role of substrate pore size in influencing nanosheet distribution has been overlooked. In this work, MoS_(2) nanosheets were dispersed in an aqueous phase to fabricate TFN membranes, investigating the effect of substrate pore size relative to the nanosheets. By systematically varying the particle size of MoS_(2) and the pore size of the substrate, we reveal how these factors impact material distribution and structural uniformity within the membranes. Our findings reveal that larger substrate pores allow the MoS_(2)-containing monomer solution to infiltrate more effectively, minimizing nanosheet aggregation. This enhances membrane performance by promoting better dispersion. Our results underscore the importance of considering the relative size of substrate pores and nanosheets in TFN membrane design, providing a pathway to improved material integration and higher membrane efficiency.展开更多
Catalyst-coated membranes(CCMs)have gained popularity among membrane electrode assembly(MEA)fabricators for their abilities and advantages compared with those of other methods,such as catalyst-coated substrates(CCSs)....Catalyst-coated membranes(CCMs)have gained popularity among membrane electrode assembly(MEA)fabricators for their abilities and advantages compared with those of other methods,such as catalyst-coated substrates(CCSs).CCMs show a profound new analysis for reducing platinum(Pt)catalyst loading.In addition,they increase the total number of reactions that occur on the MEA because of their active area amplification,which leads to an improved catalyst-utilization efficiency rate.Moreover,several characteristics are involved in the MEA fabrication methods.Material-manufacturing effects with regard to catalyst inks and analysis of the overall performance of MEAs prepared by the CCM and CCS methods are deliberated.This deliberation emphasizes the practical approaches in minimizing performance deterioration during the fabrication of MEAs using the CCM method and converses the commercialization of the CCM fabrication method toward developing an end product.Novel research is required for MEA fabrication using the CCM methods to ensure that the fuel cell performance is improved.Therefore,this review is focusing on the pros and cons of both distinguished methods,that is,CCM and CCS fabrication,for better comparison.展开更多
Thin-film composite(TFC) reverse osmosis(RO) membranes are playing the dominating role in desalination.Tremendous efforts have been put in the studies on the polyamide selective layers. However, the effect of the subs...Thin-film composite(TFC) reverse osmosis(RO) membranes are playing the dominating role in desalination.Tremendous efforts have been put in the studies on the polyamide selective layers. However, the effect of the substrate layers is far less concerned. In this review, we summarize the works that consider the impacts of the substrates, including pore sizes, surface hydrophilicity, on the processes of interfacial polymerization and consequently on the morphologies of the active layers and on final RO performances of the composite membranes. All the works indicate that the pore sizes and surface hydrophilicity of the substrate evidently influence the RO performances of the composite membranes. Unfortunately, we find that the observations and understandings on the substrate effect are frequently varied from case to case because of the lack of substrates with uniform pores and surface chemistries. We suggest using track-etched membranes or anodized alumina membranes having relatively uniform pores and functionalizable pore walls as model substrates to elucidate the substrate effect.Moreover, we argue that homoporous membranes derived from block copolymers have the potential to be used as substrates for the large-scale production of high-performances TFC RO membranes.展开更多
To develop a smart free-standing surface enhanced Raman scattering(SERS) substrate,silver nanoparticles(AgNPs) embedded temperature-sensitive nanofibrous membrane was fabricated by electrospinning their aqueous soluti...To develop a smart free-standing surface enhanced Raman scattering(SERS) substrate,silver nanoparticles(AgNPs) embedded temperature-sensitive nanofibrous membrane was fabricated by electrospinning their aqueous solution containing the copolymer poly(N-isopropylacrylamide-co-Nhydroxymethylacrylamide),followed by heat treatment to form crosslinking structure within its constituent nanofibers.To avoid negative effect of the additive like stabilizer and the reactant like reductant on their SERS efficiency,the AgNPs were in-situ synthesized through reducing Ag^+ions dissolved in the polymer solution by ultraviolet irradiation.The prepared hybrid nanofibrous membrane with high stability in aqueous medium can reach its swelling or deswelling equilibrium state within 15 seconds with the medium temperature changing between 25℃and 50℃alternately.When it was used as a free-standing SERS substrate,10^-12 mol/L of 4-nitrothiophenol in aqueous solution can be detected at room temperature,and elevating detection temperature can further lower its low detection limit.Since its generated SERS signal has desirable reproducibility,it can be used as SERS substrate for quantitative analysis.Moreover,the hybrid membrane as SERS substrate is capable of real-time monitoring the reduction of 4-nitrothiophenol into 4-aminothiophenol catalyzed by its embedded AgNPs,and the detected intermediate indicates that the reaction proceeds via a condensation route.展开更多
Metallic ion-cross-linked polymer of intrinsic microporosity(PIM-1) thin-film composite(TFC) membranes supported on an ultraviolet(UV)-cross-linked porous substrate were fabricated. The UV-cross-linked porous substrat...Metallic ion-cross-linked polymer of intrinsic microporosity(PIM-1) thin-film composite(TFC) membranes supported on an ultraviolet(UV)-cross-linked porous substrate were fabricated. The UV-cross-linked porous substrate was prepared via polymerization-induced phase separation. The PIM-1 TFC membranes were fabricated via a dip-coating procedure. Metallic ion-cross-linked PIM-1 TFC membranes were fabricated by hydrolyzing the PIM-1 TFC membrane in an alkali solution and then cross-linking it in a multivalent metallic ion solution. The pore size and porous structures were evaluated by low-temperature N_2 adsorption–desorption analysis. The membrane structure was investigated by field-emission scanning electron microscopy. The effects of heat treatment and pore-forming additives on the gas permeance of the UV-cross-linked porous substrate are reported. The effects of different pre-coating treatments on the gas permeance of the metallic ion-cross-linked PIM-1 TFC membrane are also discussed. The metallic ion-crosslinked PIM-1 TFC membrane displayed high CO_2/N_2 selectivity(23) and good CO_2 permeance(1058 GPU).展开更多
Cell fusion is a basic biological process that plays critical roles in both physiological and pathological processes.However,how mechanical factors influence the fusion process is not fully understood.In this study,we...Cell fusion is a basic biological process that plays critical roles in both physiological and pathological processes.However,how mechanical factors influence the fusion process is not fully understood.In this study,we reported filopodia-mediated fusion among MCF-7 cells.We showed that the filopodia protrusion force induced significant bending of the cell membrane,which was essential for membrane fusion between neighboring cells,and then eventually induced the formation of multinucleated syncytia.The inhibition of actin polymerization significantly reduced the fusion ratio,whereas increased actin polymerization promoted fusion.We found that several factors influence the fusion process,e.g.,the cell density,substrate pattern,and stiffness.For example,cell density has a significant effect on cell fusion.There was an optimal cell density for cell fusion.The fusion probability increased with increasing cell density within a moderate cell density range but decreased within a high cell density range.Substrate properties also influence the fusion behavior.For example,the fusion ratio was reduced on nanogrooved surfaces and soft substrates because the surface pattern restricted cell alignment and motility,and soft substrates reduced the activity of the actin dynamics of filopodia for cell fusion.This study not only contributes to our under-standing of the basic biology of cell fusion but also has important implications for understanding the mechanisms of cancer progression and potential therapeutic intervention methods.展开更多
Tendon stem/progenitor cells(TSPCs)are crucial for intrinsic regeneration of injured tendons which consume a substantial amount of energy relying on the tricarboxylic acid(TCA)cycle.Citric acid,the key substrate of th...Tendon stem/progenitor cells(TSPCs)are crucial for intrinsic regeneration of injured tendons which consume a substantial amount of energy relying on the tricarboxylic acid(TCA)cycle.Citric acid,the key substrate of the TCA cycle,emerges as a promising candidate for regulating energy metabolism.However,sus-tainable methods in providing energy metabolic substrates across the whole regenerating process has been neglected.Herein,a metabotissugenic membrane con-sisting of poly(octamethylene citrate)and L-lysine diisocyanate,POCL_(10),was developed to consistently biodegrade and provide citrate substrates.Furthermore,the POCL_(10) membrane exhibited self-sealing properties due to the introduction of strong hydrogen bonds and demonstrated anti-biofouling capacity in vitro.Intrigu-ingly,POCL_(10) showed excellent regenerative capability by promptly upregulating TSPC proliferation,energy metabolism and differentiation.In vivo,POCL_(10) was effortlessly wrapped around the injured Achilles tendon showcasing with anti-tissue adhesion and prominent collagen organization along with strengthened biomechanical properties.Hence,the development of POCL expands the reservoir of available biodegradable citrate-based biomaterials and provides a unique metabotissugenic biomaterial platform for tendon anti-biofouling and repair.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 22076075)Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control (No. 2023B1212060002)+1 种基金the Key Program of Fundamental Research from the Shenzhen Science and Technology Innovation Commission (No. JCYJ20220818100218039)the General Program of Fundamental Research from the Shenzhen Science and Technology Innovation Commission (No. JCY20230807092500001)。
文摘Thin-film nanocomposite(TFN) membranes have garnered considerable attention for their potential to improve separation performance by incorporating nanomaterials. However, challenges such as these materials' uneven distribution and aggregation have hindered practical applications. While prior studies have largely concentrated on modifying nanosheets for compatibility with polymer matrices, the role of substrate pore size in influencing nanosheet distribution has been overlooked. In this work, MoS_(2) nanosheets were dispersed in an aqueous phase to fabricate TFN membranes, investigating the effect of substrate pore size relative to the nanosheets. By systematically varying the particle size of MoS_(2) and the pore size of the substrate, we reveal how these factors impact material distribution and structural uniformity within the membranes. Our findings reveal that larger substrate pores allow the MoS_(2)-containing monomer solution to infiltrate more effectively, minimizing nanosheet aggregation. This enhances membrane performance by promoting better dispersion. Our results underscore the importance of considering the relative size of substrate pores and nanosheets in TFN membrane design, providing a pathway to improved material integration and higher membrane efficiency.
基金The authors acknowledge the financial support provided by the Ministry of Higher Education,Malaysia through the research grants LRGS/2013/UKM-UKM/TP-01 and UKM GUP-2016-044.9.0.
文摘Catalyst-coated membranes(CCMs)have gained popularity among membrane electrode assembly(MEA)fabricators for their abilities and advantages compared with those of other methods,such as catalyst-coated substrates(CCSs).CCMs show a profound new analysis for reducing platinum(Pt)catalyst loading.In addition,they increase the total number of reactions that occur on the MEA because of their active area amplification,which leads to an improved catalyst-utilization efficiency rate.Moreover,several characteristics are involved in the MEA fabrication methods.Material-manufacturing effects with regard to catalyst inks and analysis of the overall performance of MEAs prepared by the CCM and CCS methods are deliberated.This deliberation emphasizes the practical approaches in minimizing performance deterioration during the fabrication of MEAs using the CCM method and converses the commercialization of the CCM fabrication method toward developing an end product.Novel research is required for MEA fabrication using the CCM methods to ensure that the fuel cell performance is improved.Therefore,this review is focusing on the pros and cons of both distinguished methods,that is,CCM and CCS fabrication,for better comparison.
基金Supported by the National Basic Research Program of China(2015CB655301)the Natural Science Foundation of Jiangsu Province(BK20150063)the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Thin-film composite(TFC) reverse osmosis(RO) membranes are playing the dominating role in desalination.Tremendous efforts have been put in the studies on the polyamide selective layers. However, the effect of the substrate layers is far less concerned. In this review, we summarize the works that consider the impacts of the substrates, including pore sizes, surface hydrophilicity, on the processes of interfacial polymerization and consequently on the morphologies of the active layers and on final RO performances of the composite membranes. All the works indicate that the pore sizes and surface hydrophilicity of the substrate evidently influence the RO performances of the composite membranes. Unfortunately, we find that the observations and understandings on the substrate effect are frequently varied from case to case because of the lack of substrates with uniform pores and surface chemistries. We suggest using track-etched membranes or anodized alumina membranes having relatively uniform pores and functionalizable pore walls as model substrates to elucidate the substrate effect.Moreover, we argue that homoporous membranes derived from block copolymers have the potential to be used as substrates for the large-scale production of high-performances TFC RO membranes.
基金the National Natural Science Foundation of China(Nos.51503033,51373030)
文摘To develop a smart free-standing surface enhanced Raman scattering(SERS) substrate,silver nanoparticles(AgNPs) embedded temperature-sensitive nanofibrous membrane was fabricated by electrospinning their aqueous solution containing the copolymer poly(N-isopropylacrylamide-co-Nhydroxymethylacrylamide),followed by heat treatment to form crosslinking structure within its constituent nanofibers.To avoid negative effect of the additive like stabilizer and the reactant like reductant on their SERS efficiency,the AgNPs were in-situ synthesized through reducing Ag^+ions dissolved in the polymer solution by ultraviolet irradiation.The prepared hybrid nanofibrous membrane with high stability in aqueous medium can reach its swelling or deswelling equilibrium state within 15 seconds with the medium temperature changing between 25℃and 50℃alternately.When it was used as a free-standing SERS substrate,10^-12 mol/L of 4-nitrothiophenol in aqueous solution can be detected at room temperature,and elevating detection temperature can further lower its low detection limit.Since its generated SERS signal has desirable reproducibility,it can be used as SERS substrate for quantitative analysis.Moreover,the hybrid membrane as SERS substrate is capable of real-time monitoring the reduction of 4-nitrothiophenol into 4-aminothiophenol catalyzed by its embedded AgNPs,and the detected intermediate indicates that the reaction proceeds via a condensation route.
基金Supported by the National Natural Science Foundation of China(21506160,21776217)the Science and Technology Plans of Tianjin(16PTSYJC00110)
文摘Metallic ion-cross-linked polymer of intrinsic microporosity(PIM-1) thin-film composite(TFC) membranes supported on an ultraviolet(UV)-cross-linked porous substrate were fabricated. The UV-cross-linked porous substrate was prepared via polymerization-induced phase separation. The PIM-1 TFC membranes were fabricated via a dip-coating procedure. Metallic ion-cross-linked PIM-1 TFC membranes were fabricated by hydrolyzing the PIM-1 TFC membrane in an alkali solution and then cross-linking it in a multivalent metallic ion solution. The pore size and porous structures were evaluated by low-temperature N_2 adsorption–desorption analysis. The membrane structure was investigated by field-emission scanning electron microscopy. The effects of heat treatment and pore-forming additives on the gas permeance of the UV-cross-linked porous substrate are reported. The effects of different pre-coating treatments on the gas permeance of the metallic ion-cross-linked PIM-1 TFC membrane are also discussed. The metallic ion-crosslinked PIM-1 TFC membrane displayed high CO_2/N_2 selectivity(23) and good CO_2 permeance(1058 GPU).
基金supported by the National Natural Science Foundation of China(Grant Nos.11932017 and 12122212).
文摘Cell fusion is a basic biological process that plays critical roles in both physiological and pathological processes.However,how mechanical factors influence the fusion process is not fully understood.In this study,we reported filopodia-mediated fusion among MCF-7 cells.We showed that the filopodia protrusion force induced significant bending of the cell membrane,which was essential for membrane fusion between neighboring cells,and then eventually induced the formation of multinucleated syncytia.The inhibition of actin polymerization significantly reduced the fusion ratio,whereas increased actin polymerization promoted fusion.We found that several factors influence the fusion process,e.g.,the cell density,substrate pattern,and stiffness.For example,cell density has a significant effect on cell fusion.There was an optimal cell density for cell fusion.The fusion probability increased with increasing cell density within a moderate cell density range but decreased within a high cell density range.Substrate properties also influence the fusion behavior.For example,the fusion ratio was reduced on nanogrooved surfaces and soft substrates because the surface pattern restricted cell alignment and motility,and soft substrates reduced the activity of the actin dynamics of filopodia for cell fusion.This study not only contributes to our under-standing of the basic biology of cell fusion but also has important implications for understanding the mechanisms of cancer progression and potential therapeutic intervention methods.
基金supported by National Key R&D Program of China(2024YFA1107800)National Natural Science Foundation of China(Grant No.52403205,82172408,82425035 and 9236810338)+8 种基金Shanghai Jiao Tong University Medical College“Two-hundred Talent”Program(No.20191829)Program of Shanghai Academic/Technology Research Leader(No.22XD1422600)Shanghai Municipal Health Commission(No.2022YQ073)The Second Three-Year Action Plan for Promoting Clinical Skills and Clinical Innovation in Municipal Hospitals of Shanghai Shenkang(No.SHDC2020CR4032)Original Exploration project of Shanghai Science and Technology Innovation Action Plan(No.22ZR1480300)Shanghai“Medical Star”Young Medical Talent Training Funding Program(Outstanding Youth)Shanghai Health Commission Health Industry Research Project(Excellent Project)Shanghai Municipal Health Commission Research Project(No.20234Z0008)Foundation of Muyuan Laboratory(Program ID:13166022401).
文摘Tendon stem/progenitor cells(TSPCs)are crucial for intrinsic regeneration of injured tendons which consume a substantial amount of energy relying on the tricarboxylic acid(TCA)cycle.Citric acid,the key substrate of the TCA cycle,emerges as a promising candidate for regulating energy metabolism.However,sus-tainable methods in providing energy metabolic substrates across the whole regenerating process has been neglected.Herein,a metabotissugenic membrane con-sisting of poly(octamethylene citrate)and L-lysine diisocyanate,POCL_(10),was developed to consistently biodegrade and provide citrate substrates.Furthermore,the POCL_(10) membrane exhibited self-sealing properties due to the introduction of strong hydrogen bonds and demonstrated anti-biofouling capacity in vitro.Intrigu-ingly,POCL_(10) showed excellent regenerative capability by promptly upregulating TSPC proliferation,energy metabolism and differentiation.In vivo,POCL_(10) was effortlessly wrapped around the injured Achilles tendon showcasing with anti-tissue adhesion and prominent collagen organization along with strengthened biomechanical properties.Hence,the development of POCL expands the reservoir of available biodegradable citrate-based biomaterials and provides a unique metabotissugenic biomaterial platform for tendon anti-biofouling and repair.
