In this study,the effects of low-dose sodium hypochlorite disinfection on water quality and biofilm growth in drinking water distribution systems(DWDS)after ultrafiltration pretreatment was investigated.The influence ...In this study,the effects of low-dose sodium hypochlorite disinfection on water quality and biofilm growth in drinking water distribution systems(DWDS)after ultrafiltration pretreatment was investigated.The influence of pipeline hydraulic residence time(HRT)on disinfection efficiency,by-product formation,microbial activity,and biofilm growth were considered.The results show that both microbial activities and metabolite secretion were stimulated by increasing HRT,aggravating the potential risk of microbial pollution in DWDS.The enhanced microbial metabolism could further weaken disinfection efficiency by consuming extra residual Chlorine,after which the formation of disinfection by-products was facilitated.Residual Chlorine was found negatively correlated with HRT.With prolonging HRT from 5 to 40 h,the concentration of disinfection by-products(Chlorate,Chlorite,and Trichloromethane)was on a continuously increasing trend by 37%,140%,and 75%,respectively.But the water kept in pipeline still reliably satisfied the Standards for drinking water quality in China(GB5749–2022).Besides,more biofilm with denser morphologies developed on rubber pipeline gaskets rather than the iron/plastic ones.Rubber material was inappropriate for DWDS due to its potential risk of secondary biological pollution.Prolonging HRT also enhanced the accumulation of dominant bacteria(e.g.Bradyrhizobium and Obscuribacter)and decreased microbial diversity.展开更多
Coagulation–ultrafiltration(C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the developmen...Coagulation–ultrafiltration(C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the development of membrane fouling. In this study, we built a dynamic C–UF set-up to carry out the treatment of micro-polluted surface water, to investigate the characteristics of dissolved organic matter from different units. The influences of poly aluminum chloride and poly dimethyldiallylammonium chloride(PDMDAAC) on removal efficiency and membrane fouling were also investigated. Results showed that the dosage of PDMDAAC evidently increased the UV254 and dissolved organic carbon removal efficiencies,and thereby alleviated membrane fouling in the C–UF process. Most hydrophobic bases(HoB)and hydrophobic neutral fractions could be removed by coagulation. Similarly, UF was good at removing HoB compared to hydrophilic substances(HiS) and hydrophobic acid(HoA)fractions. HiS and HoA fractions with low molecule weight accumulated on the surface of the membrane, causing the increase of transmembrane pressure(TMP). Membrane fouling was mainly caused by a removable cake layer, and mechanical cleaning was an efficient way to decrease the TMP.展开更多
Surface charge characteristics of a membrane can be determined by the streaming potential. In order to obtain more accurate streaming potential value during the measurement, four measurement operation modes were inves...Surface charge characteristics of a membrane can be determined by the streaming potential. In order to obtain more accurate streaming potential value during the measurement, four measurement operation modes were investigated in this study, and among the four modes, the steady mode with pressure stepped downward was considered the best one. Experimental results showed that the effects of compaction on the streaming potential measurement for a microfiltration membrane was more obvious than that for a ultrafiltration membrane. Both feed pH and presoaking could affect the measurement of streaming potential.展开更多
The efficiency of advanced membranes towards removal of general and specific microbes from wastewater was investigated. The treatment included a subsequent system of activated sludge, ultrafiltration （hollow fibre me...The efficiency of advanced membranes towards removal of general and specific microbes from wastewater was investigated. The treatment included a subsequent system of activated sludge, ultrafiltration （hollow fibre membranes with 100 kDa cut-off, and spiral wound membranes with 20 kDa cut-off）, and RO （reverse osmosis）. The removal evaluation of screened microbes present in treated wastewater showed that hollow fibre membrane rejected only 1 log （90% rejection） of the TPC （total microbial count）, TC （total coliforms）, and FC （faecal coliforms）. A higher effectiveness was observed with spiral wound, removing 2-3 logs （99%-99.9%） of TPC and complete rejection of TC and FC. The RO system was successful in total rejection of all received bacteria. The removal evaluation of inoculated specific types of bacteria showed that the hollow membranes removed 2 logs （99%） of inoculated E. coli （10^7-10^8 cfu/mL inoculum）, 2-3 logs （99%-99.9%） of Enterococus spp. （10^7-10^10 cfu/mL inoculum）, 1-2 logs （90%-99%） of Salmonella （10^8-10^10 cfu/mL inoculum） and 1-2 logs （90%-99%） of Shigella （10^5-10^6 cfu/mL inoculum）. The spiral wound was significantly efficient in rejecting further 3 logs of E. coil, 5 logs of Enterococus spp., 4 logs of Salmonella, and a complete rejection of all received bacteria was accomplished by RO membrane. The results indicate that Gram positive bacteria were removed much more efficiently compared to the Gram negative ones, the rationale behind such behaviour is based on cell walls elasticity.展开更多
Surface charge characteristics of a membrane can be determined by the streaming potential. In order to obtain more accurate streaming potential value during the measurement, four measurement operation modes were inves...Surface charge characteristics of a membrane can be determined by the streaming potential. In order to obtain more accurate streaming potential value during the measurement, four measurement operation modes were investigated in this study, and among the four modes, the steady mode with pressure stepped downward was con- sidered the best one. Experimental results showed that the effects of compaction on the streaming potential meas- urement for a microfiltration membrane was more obvious than that for a ultrafiltration membrane. Both feed pH and presoaking could affect the measurement of streaming potential.展开更多
Phosphorylated sugars,recognized as central intermediates in carbohydrate metabolism and critical precursors for enzymatic synthesis of rare sugars,face significant technical barriers in their industrialscale producti...Phosphorylated sugars,recognized as central intermediates in carbohydrate metabolism and critical precursors for enzymatic synthesis of rare sugars,face significant technical barriers in their industrialscale production.The multi-enzymatic preparation systems for these compounds inherently accumulate complex impurities,including protein-based catalysts,residual substrates,and oligosaccharide byproducts,posing persistent challenges in product separation and biocatalyst recycling.To address this limitation,we conducted a systematic investigation of ultrafiltration-based separation strategies during the multi-enzyme-catalyzed synthesis of fructose-1,6-bisphosphate(FDP),with particular emphasis on membrane fouling mechanisms.By screening the ultrafiltration membranes,UE020 showed the best performance in the model system,achieving significant separation targets:99.97% retention of bovine serum albumin,FDP/maltodextrin separation coefficient of 7.41,and FDP recovery of 93.63%.An analysis of the components of resistance revealed that concentration polarization induced by maltodextrin was the main factor constituting the resistance,irreversible resistance due to bovine serum albumin was a secondary effect,and the resistance constituted by FDP was negligible.A mitigation strategy employing powdered activated carbon for dynamic membrane formation significantly improved system performance,reducing irreversible resistance by 59.14% and enhancing flux recovery by 20.85%.In this study,ultrafiltration was strategically employed to achieve efficient separation of FDP and enzyme recovery.Significantly,we deciphered the synergistic fouling mechanisms arising from interactions within the multicomponent system containing phosphorylated sugars,oligosaccharides,and proteins.These findings provide a mechanistic framework for scaling up multi-enzymatic systems dedicated to phosphorylated sugar biosynthesis,effectively bridging the gap between laboratory-scale synthesis and industrial implementation.展开更多
This study synthesizes and evaluates a novel polysulfone-based membrane doped with graphene oxidepolyethyleneimine-silicon oxide(GO-SiO_(2)-PEI),specifically designed for oily water treatment applications.The function...This study synthesizes and evaluates a novel polysulfone-based membrane doped with graphene oxidepolyethyleneimine-silicon oxide(GO-SiO_(2)-PEI),specifically designed for oily water treatment applications.The functionalization of graphene oxide with SiO_(2) and PEI was rigorously confirmed through comprehensive XRD,FTIR,Raman spectroscopy,and XPS analyses,ensuring the integrity and expected functionality of the nanocomposite.This nanocomposite was integrated into the polysulfone(PSF)membrane matrix,significantly reducing the membrane's inherent hydrophobicity and propensity for fouling.The membranes were meticulously characterized using advanced surface and bulk sensitive apparatus including contact angle and SEM imaging to ascertain their structural and functional attributes.Performance evaluations conducted in a dead-end filtration setup revealed that incorporating 1.0%(mass) of the nanocomposite into the PSF membrane markedly enhanced its porosity and improved the water contact angle.This modification led to an 809% increase in the membrane's water flux and a 57%enhancement in flux recovery rate,while still maintaining a high oil rejection rate and a relatively low leaching rate of 5.3 mg·L^(-1).Analysis through the Owens-Wendt-Kaelble model indicated a significant increase in polar surface energy,corroborating the improved oil rejection capabilities at elevated flux levels.Fouling behavior,analyzed using Hermia's model,identified cake formation as the primary fouling mechanism in most of the tested membranes.Leaching tests further highlighted those membranes with higher nanocomposite loadings exhibited increased leaching rates,suggesting a trade-off between performance enhancement and material stability.展开更多
[Objective] The study aimed to discover the effects of powder active carbon（ PAC） /flotation /micro-flocculation /ultrafiltration combined process on the treatment of reservoir water. [Method]Taken the water from a ...[Objective] The study aimed to discover the effects of powder active carbon（ PAC） /flotation /micro-flocculation /ultrafiltration combined process on the treatment of reservoir water. [Method]Taken the water from a mountainous reservoir for the initial samples,the parameters such as turbidity,COD Mn,chlorophyll-a and methylisobormeol（ MIB） of water samples were monitored before and after treated with combined processes of micro-flocculation /ultrafiltration, flotation /micro-flocculation /ultrafiltration, PAC /flotation /micro-flocculation /ultrafiltration. [Result] The results showed that the removal rates of turbidity of water samples by the above three processes were 97. 5%,98. 0% and 98. 6%,respectively. The removal rates of COD Mn were 30. 9%,35. 0% and 52. 0%. The removal rates of chlorophyll-a were 80. 6%,91. 0% and 99. 0%. The removal rates of MIB were 17. 0%,34. 2% and 97. 0%. [Conclusion]The PAC /flotation /micro-flocculation ultrafiltration combined process can be flexibly combined based on the characteristics of algae and odor in water,and is suitable for water plant construction or reconstruction.展开更多
Micro/nanoplastics(M/NPs)have become pervasive environmental pollutants,posing significant risks to human health through various exposure routes,including ingestion,inhalation,and direct contact.This review systematic...Micro/nanoplastics(M/NPs)have become pervasive environmental pollutants,posing significant risks to human health through various exposure routes,including ingestion,inhalation,and direct contact.This review systematically examined the potential impacts of M/NPs on ocular health,focusing on exposure pathways,toxicological mechanisms,and resultant damage to the eye.Ocular exposure to M/NPs can occur via direct contact and oral ingestion,with the latter potentially leading to the penetration of particles through ocular biological barriers into ocular tissues.The review highlighted that M/NPs can induce adverse effects on the ocular surface,elevate intraocular pressure,and cause abnormalities in the vitreous and retina.Mechanistically,oxidative stress and inflammation are central to M/NP-induced ocular damage,with smaller particles often exhibiting greater toxicity.Overall,this review underscored the potential risks of M/NPs to ocular health and emphasized the need for further research to elucidate exposure mechanisms,toxicological pathways,and mitigation strategies.展开更多
Micro silicon(mSi)is a promising anode candidate for all-solid-state batteries due to its high specific capacity,low side reactions,and high tap density.However,silicon suffers from its poor electronic and ionic condu...Micro silicon(mSi)is a promising anode candidate for all-solid-state batteries due to its high specific capacity,low side reactions,and high tap density.However,silicon suffers from its poor electronic and ionic conductivity,which is particularly severe on a micro scale and in solid-state systems,leading to increased polarization and inferior electrochemical performance.Doping can broaden the transmission pathways and reduce the diffusion energy barrier for electrons and lithium ions.However,achieving effective,uniform doping in mSi is challenging due to its longer diffusion paths and higher energy barriers.Therefore,current doping research is primarily limited to nanosilicon.In this study,we successfully used a Joule-heating activated staged thermal treatment to achieve full-depth doping of germanium(Ge)in the mSi substrate.The Joule-heating process activated the mSi substrate,resulting in abundant vacancy defects that reduced the diffusion barrier of Ge into the silicon lattice and facilitated full-depth Ge doping.Surprisingly,the resulting Si-Ge anode exhibited significantly enhanced electrical conductivity(70 times).Meanwhile,the improved Li-ion conductivity in mSi and the reduced Young’s modulus enhance the electrode reaction kinetics and integrity after cycling.Ge-doped silicon anodes demonstrate excellent electrochemical performance when applied in sulfide solid-state half-cells and full-cells.This work provides substantial insights into the rational structural design of mSi alloyed anode materials,paving the way for the development of high-performance solid-state Li-ion batteries.展开更多
Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always...Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications.展开更多
The deployment of flexible zinc-ion batteries is impeded by dendrite growth from random anode defects.Conventional defect-elimination strategies often compromise flexibility and fail to achieve uniform interfaces.We p...The deployment of flexible zinc-ion batteries is impeded by dendrite growth from random anode defects.Conventional defect-elimination strategies often compromise flexibility and fail to achieve uniform interfaces.We propose a paradigm shift:reconfiguring random defects into engineered,monodisperse artificial micro-curves to homogenize electric fields and guide aligned zinc(Zn)deposition.Using moisture-assisted flash heating,we transform zincophilic silver(Ag)coatings on carbon fibers into uniformly dispersed micro-curved particles(Ag Particles@CC),creating identical nucleation sites with optimal zinc ion(Zn^(2+))adsorption energetics.Theoretical simulations confirm these structures eliminate localized field concentrations,enabling homogeneous plating/stripping.This design demonstrates remarkable performance,with ultrastable 1500 cycles at 10 mA cm^(-2)(98.6%avg.Coulombic efficiency)and symmetric cell operation>650 h(57.7 mV hysteresis).Crucially,interparticle discontinuities preserve intrinsic flexibility,enabling flexible pouch cells(Ag Particles@CC-Zn//NaV_(3)O_(8)·1,5H_(2)O)to successfully power wearable devices such as smartwatches and smartphones.This work establishes defect reconfiguration via artificial micro-curvature engineering as a universal strategy toward dendritesuppressed,flexible energy storage.展开更多
Aluminum scandium nitride(AlScN),an emergingⅢ-nitride semiconductor material,has attracted significant atten-tion in recent years due to its exceptional piezoelectric properties,high thermal stability,tunable bandgap...Aluminum scandium nitride(AlScN),an emergingⅢ-nitride semiconductor material,has attracted significant atten-tion in recent years due to its exceptional piezoelectric properties,high thermal stability,tunable bandgap,and excellent com-patibility with micro/nano fabrication.This paper systematically reviews the crystal structure,fundamental properties,and prop-erty modulation mechanisms of AlScN.It also summarizes recent progress in micro/nano fabrication technologies,including deposition,etching,and device integration.Furthermore,the applications of AlScN in diverse fields such as micro-electrome-chanical systems(MEMS),RF communications,energy conversion,optoelectronics and sensors are discussed.Finally,current challenges and promising future research directions for AlScN are outlined.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52170070,52400022,and 52200088)the Youth S&T Talent Support Programme of Guangdong Provincial Association for Science and Technology(GDSTA)(No.SKXRC202406)+1 种基金the“One hundred Youth”Science and Technology Plan,Guangdong University of Technology,China(No.263113906)China Postdoctoral Science Foundation(No.2023M740754).
文摘In this study,the effects of low-dose sodium hypochlorite disinfection on water quality and biofilm growth in drinking water distribution systems(DWDS)after ultrafiltration pretreatment was investigated.The influence of pipeline hydraulic residence time(HRT)on disinfection efficiency,by-product formation,microbial activity,and biofilm growth were considered.The results show that both microbial activities and metabolite secretion were stimulated by increasing HRT,aggravating the potential risk of microbial pollution in DWDS.The enhanced microbial metabolism could further weaken disinfection efficiency by consuming extra residual Chlorine,after which the formation of disinfection by-products was facilitated.Residual Chlorine was found negatively correlated with HRT.With prolonging HRT from 5 to 40 h,the concentration of disinfection by-products(Chlorate,Chlorite,and Trichloromethane)was on a continuously increasing trend by 37%,140%,and 75%,respectively.But the water kept in pipeline still reliably satisfied the Standards for drinking water quality in China(GB5749–2022).Besides,more biofilm with denser morphologies developed on rubber pipeline gaskets rather than the iron/plastic ones.Rubber material was inappropriate for DWDS due to its potential risk of secondary biological pollution.Prolonging HRT also enhanced the accumulation of dominant bacteria(e.g.Bradyrhizobium and Obscuribacter)and decreased microbial diversity.
基金supported by the National Natural Science Foundation of China (No.51678349)the Tai Shan Scholar Foundation (No.ts201511003)
文摘Coagulation–ultrafiltration(C–UF) is widely used for surface water treatment. With the removal of pollutants, the characteristics of organic matter change and affect the final treatment efficiency and the development of membrane fouling. In this study, we built a dynamic C–UF set-up to carry out the treatment of micro-polluted surface water, to investigate the characteristics of dissolved organic matter from different units. The influences of poly aluminum chloride and poly dimethyldiallylammonium chloride(PDMDAAC) on removal efficiency and membrane fouling were also investigated. Results showed that the dosage of PDMDAAC evidently increased the UV254 and dissolved organic carbon removal efficiencies,and thereby alleviated membrane fouling in the C–UF process. Most hydrophobic bases(HoB)and hydrophobic neutral fractions could be removed by coagulation. Similarly, UF was good at removing HoB compared to hydrophilic substances(HiS) and hydrophobic acid(HoA)fractions. HiS and HoA fractions with low molecule weight accumulated on the surface of the membrane, causing the increase of transmembrane pressure(TMP). Membrane fouling was mainly caused by a removable cake layer, and mechanical cleaning was an efficient way to decrease the TMP.
基金the National Natural Science Foundation of China （No.29976031）, the Collaboration Project Foundation of Tianjin University and Nankal University, and the Key Project Foundation of Tianjin （No.0331810112）.
文摘Surface charge characteristics of a membrane can be determined by the streaming potential. In order to obtain more accurate streaming potential value during the measurement, four measurement operation modes were investigated in this study, and among the four modes, the steady mode with pressure stepped downward was considered the best one. Experimental results showed that the effects of compaction on the streaming potential measurement for a microfiltration membrane was more obvious than that for a ultrafiltration membrane. Both feed pH and presoaking could affect the measurement of streaming potential.
文摘The efficiency of advanced membranes towards removal of general and specific microbes from wastewater was investigated. The treatment included a subsequent system of activated sludge, ultrafiltration （hollow fibre membranes with 100 kDa cut-off, and spiral wound membranes with 20 kDa cut-off）, and RO （reverse osmosis）. The removal evaluation of screened microbes present in treated wastewater showed that hollow fibre membrane rejected only 1 log （90% rejection） of the TPC （total microbial count）, TC （total coliforms）, and FC （faecal coliforms）. A higher effectiveness was observed with spiral wound, removing 2-3 logs （99%-99.9%） of TPC and complete rejection of TC and FC. The RO system was successful in total rejection of all received bacteria. The removal evaluation of inoculated specific types of bacteria showed that the hollow membranes removed 2 logs （99%） of inoculated E. coli （10^7-10^8 cfu/mL inoculum）, 2-3 logs （99%-99.9%） of Enterococus spp. （10^7-10^10 cfu/mL inoculum）, 1-2 logs （90%-99%） of Salmonella （10^8-10^10 cfu/mL inoculum） and 1-2 logs （90%-99%） of Shigella （10^5-10^6 cfu/mL inoculum）. The spiral wound was significantly efficient in rejecting further 3 logs of E. coil, 5 logs of Enterococus spp., 4 logs of Salmonella, and a complete rejection of all received bacteria was accomplished by RO membrane. The results indicate that Gram positive bacteria were removed much more efficiently compared to the Gram negative ones, the rationale behind such behaviour is based on cell walls elasticity.
基金Supported by the National Natural Science Foundation of China (No.29976031), the Collaboration Project Foundation of Tian-jin University and Nankai University, and the Key Project Foundation of Tianjin (No.0331810112).
文摘Surface charge characteristics of a membrane can be determined by the streaming potential. In order to obtain more accurate streaming potential value during the measurement, four measurement operation modes were investigated in this study, and among the four modes, the steady mode with pressure stepped downward was con- sidered the best one. Experimental results showed that the effects of compaction on the streaming potential meas- urement for a microfiltration membrane was more obvious than that for a ultrafiltration membrane. Both feed pH and presoaking could affect the measurement of streaming potential.
基金the funding support provided by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDC0120402)the National Key Research&Development Program of China (2022YFC2105103)。
文摘Phosphorylated sugars,recognized as central intermediates in carbohydrate metabolism and critical precursors for enzymatic synthesis of rare sugars,face significant technical barriers in their industrialscale production.The multi-enzymatic preparation systems for these compounds inherently accumulate complex impurities,including protein-based catalysts,residual substrates,and oligosaccharide byproducts,posing persistent challenges in product separation and biocatalyst recycling.To address this limitation,we conducted a systematic investigation of ultrafiltration-based separation strategies during the multi-enzyme-catalyzed synthesis of fructose-1,6-bisphosphate(FDP),with particular emphasis on membrane fouling mechanisms.By screening the ultrafiltration membranes,UE020 showed the best performance in the model system,achieving significant separation targets:99.97% retention of bovine serum albumin,FDP/maltodextrin separation coefficient of 7.41,and FDP recovery of 93.63%.An analysis of the components of resistance revealed that concentration polarization induced by maltodextrin was the main factor constituting the resistance,irreversible resistance due to bovine serum albumin was a secondary effect,and the resistance constituted by FDP was negligible.A mitigation strategy employing powdered activated carbon for dynamic membrane formation significantly improved system performance,reducing irreversible resistance by 59.14% and enhancing flux recovery by 20.85%.In this study,ultrafiltration was strategically employed to achieve efficient separation of FDP and enzyme recovery.Significantly,we deciphered the synergistic fouling mechanisms arising from interactions within the multicomponent system containing phosphorylated sugars,oligosaccharides,and proteins.These findings provide a mechanistic framework for scaling up multi-enzymatic systems dedicated to phosphorylated sugar biosynthesis,effectively bridging the gap between laboratory-scale synthesis and industrial implementation.
基金made possible by Qatar University internal grant(i-GA-379)graduate sponsorship research award (GSRA7-1-0510-20046) from Qatar National Research Fund (QNRF)。
文摘This study synthesizes and evaluates a novel polysulfone-based membrane doped with graphene oxidepolyethyleneimine-silicon oxide(GO-SiO_(2)-PEI),specifically designed for oily water treatment applications.The functionalization of graphene oxide with SiO_(2) and PEI was rigorously confirmed through comprehensive XRD,FTIR,Raman spectroscopy,and XPS analyses,ensuring the integrity and expected functionality of the nanocomposite.This nanocomposite was integrated into the polysulfone(PSF)membrane matrix,significantly reducing the membrane's inherent hydrophobicity and propensity for fouling.The membranes were meticulously characterized using advanced surface and bulk sensitive apparatus including contact angle and SEM imaging to ascertain their structural and functional attributes.Performance evaluations conducted in a dead-end filtration setup revealed that incorporating 1.0%(mass) of the nanocomposite into the PSF membrane markedly enhanced its porosity and improved the water contact angle.This modification led to an 809% increase in the membrane's water flux and a 57%enhancement in flux recovery rate,while still maintaining a high oil rejection rate and a relatively low leaching rate of 5.3 mg·L^(-1).Analysis through the Owens-Wendt-Kaelble model indicated a significant increase in polar surface energy,corroborating the improved oil rejection capabilities at elevated flux levels.Fouling behavior,analyzed using Hermia's model,identified cake formation as the primary fouling mechanism in most of the tested membranes.Leaching tests further highlighted those membranes with higher nanocomposite loadings exhibited increased leaching rates,suggesting a trade-off between performance enhancement and material stability.
基金Supported by Water Pollution Control and Treatment National Science and Technology Major Project(2012ZX07404-003)Major Projects of Science and Technology of Jinan City(201201133)
文摘[Objective] The study aimed to discover the effects of powder active carbon（ PAC） /flotation /micro-flocculation /ultrafiltration combined process on the treatment of reservoir water. [Method]Taken the water from a mountainous reservoir for the initial samples,the parameters such as turbidity,COD Mn,chlorophyll-a and methylisobormeol（ MIB） of water samples were monitored before and after treated with combined processes of micro-flocculation /ultrafiltration, flotation /micro-flocculation /ultrafiltration, PAC /flotation /micro-flocculation /ultrafiltration. [Result] The results showed that the removal rates of turbidity of water samples by the above three processes were 97. 5%,98. 0% and 98. 6%,respectively. The removal rates of COD Mn were 30. 9%,35. 0% and 52. 0%. The removal rates of chlorophyll-a were 80. 6%,91. 0% and 99. 0%. The removal rates of MIB were 17. 0%,34. 2% and 97. 0%. [Conclusion]The PAC /flotation /micro-flocculation ultrafiltration combined process can be flexibly combined based on the characteristics of algae and odor in water,and is suitable for water plant construction or reconstruction.
基金Supported by the Guangdong Provincial Natural Science Foundation(No.2114050001527).
文摘Micro/nanoplastics(M/NPs)have become pervasive environmental pollutants,posing significant risks to human health through various exposure routes,including ingestion,inhalation,and direct contact.This review systematically examined the potential impacts of M/NPs on ocular health,focusing on exposure pathways,toxicological mechanisms,and resultant damage to the eye.Ocular exposure to M/NPs can occur via direct contact and oral ingestion,with the latter potentially leading to the penetration of particles through ocular biological barriers into ocular tissues.The review highlighted that M/NPs can induce adverse effects on the ocular surface,elevate intraocular pressure,and cause abnormalities in the vitreous and retina.Mechanistically,oxidative stress and inflammation are central to M/NP-induced ocular damage,with smaller particles often exhibiting greater toxicity.Overall,this review underscored the potential risks of M/NPs to ocular health and emphasized the need for further research to elucidate exposure mechanisms,toxicological pathways,and mitigation strategies.
基金financially supported by the National Key Research and Development Program(2022YFE0127400)the National Natural Science Foundation of China(52172040,52202041,and U23B2077)+1 种基金Taishan Scholar Project of Shandong Province(tsqn202211086,ts202208832,tsqnz20221118)the Fundamental Research Funds for the Central Universities(23CX06055A).
文摘Micro silicon(mSi)is a promising anode candidate for all-solid-state batteries due to its high specific capacity,low side reactions,and high tap density.However,silicon suffers from its poor electronic and ionic conductivity,which is particularly severe on a micro scale and in solid-state systems,leading to increased polarization and inferior electrochemical performance.Doping can broaden the transmission pathways and reduce the diffusion energy barrier for electrons and lithium ions.However,achieving effective,uniform doping in mSi is challenging due to its longer diffusion paths and higher energy barriers.Therefore,current doping research is primarily limited to nanosilicon.In this study,we successfully used a Joule-heating activated staged thermal treatment to achieve full-depth doping of germanium(Ge)in the mSi substrate.The Joule-heating process activated the mSi substrate,resulting in abundant vacancy defects that reduced the diffusion barrier of Ge into the silicon lattice and facilitated full-depth Ge doping.Surprisingly,the resulting Si-Ge anode exhibited significantly enhanced electrical conductivity(70 times).Meanwhile,the improved Li-ion conductivity in mSi and the reduced Young’s modulus enhance the electrode reaction kinetics and integrity after cycling.Ge-doped silicon anodes demonstrate excellent electrochemical performance when applied in sulfide solid-state half-cells and full-cells.This work provides substantial insights into the rational structural design of mSi alloyed anode materials,paving the way for the development of high-performance solid-state Li-ion batteries.
基金supported by Young Elite Scientists Sponsorship Program by China Association for Science and Technology(No.2022QNRC001)the National Natural Science Foundation of China(No.52273053)the Chenguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.21CGA41)。
文摘Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications.
基金supported by the National Natural Science Foundation of China(52202218)the Fundamental Research Funds for the Central Universities(CUSF-DH-T-2023044)。
文摘The deployment of flexible zinc-ion batteries is impeded by dendrite growth from random anode defects.Conventional defect-elimination strategies often compromise flexibility and fail to achieve uniform interfaces.We propose a paradigm shift:reconfiguring random defects into engineered,monodisperse artificial micro-curves to homogenize electric fields and guide aligned zinc(Zn)deposition.Using moisture-assisted flash heating,we transform zincophilic silver(Ag)coatings on carbon fibers into uniformly dispersed micro-curved particles(Ag Particles@CC),creating identical nucleation sites with optimal zinc ion(Zn^(2+))adsorption energetics.Theoretical simulations confirm these structures eliminate localized field concentrations,enabling homogeneous plating/stripping.This design demonstrates remarkable performance,with ultrastable 1500 cycles at 10 mA cm^(-2)(98.6%avg.Coulombic efficiency)and symmetric cell operation>650 h(57.7 mV hysteresis).Crucially,interparticle discontinuities preserve intrinsic flexibility,enabling flexible pouch cells(Ag Particles@CC-Zn//NaV_(3)O_(8)·1,5H_(2)O)to successfully power wearable devices such as smartwatches and smartphones.This work establishes defect reconfiguration via artificial micro-curvature engineering as a universal strategy toward dendritesuppressed,flexible energy storage.
基金supported by the National Natural Science Foundation of China(General Program,No.52473331).
文摘Aluminum scandium nitride(AlScN),an emergingⅢ-nitride semiconductor material,has attracted significant atten-tion in recent years due to its exceptional piezoelectric properties,high thermal stability,tunable bandgap,and excellent com-patibility with micro/nano fabrication.This paper systematically reviews the crystal structure,fundamental properties,and prop-erty modulation mechanisms of AlScN.It also summarizes recent progress in micro/nano fabrication technologies,including deposition,etching,and device integration.Furthermore,the applications of AlScN in diverse fields such as micro-electrome-chanical systems(MEMS),RF communications,energy conversion,optoelectronics and sensors are discussed.Finally,current challenges and promising future research directions for AlScN are outlined.
