In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by io...In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by ion morphology pretreatme nt and solvent extraction.An acidic V(Ⅴ)/W(Ⅵ)solution was obtained using the me mbrane electrolysis method without adding any other chemical reagents.In addition,Na was recovered in the form of NaOH by product,avoiding the generation of Na containing wastewater.The electrolysis parameters were investigated,the lowest power consumption of 3063 kW·h·t^(-1)NaOH was obtained at a current density of 125 A·m^(-2)and an initial NaOH concentration of 2 mol·L^(-1).After electrolysis,oxalic acid was added to the acidic V/W containing solution,converting V(Ⅴ)negative ion to V(Ⅳ)positive ion.Since W(Ⅵ)ion state remained in negative form,the generation of heteropolyacid ions(W_(x)V_(y)O_(z)^(n-))was prevented.It was found that under the condition of oxalic acid addition/theoretical consumption 1.2 and reaction temperature 75℃,100%V(Ⅴ)was co nverted to V(Ⅳ4).Using 10%N263+10%noctanol+80%sulfonated kerosene as extractant,the highest W(Ⅵ)/V(Ⅳ)separation coefficient of 7559.76was obtained at pH=1.8,O:A ratio=1:1 and extraction time 15 min.With 2 mol·L^(-1)NaOH as stripping reagent,the W stripping efficiency reached 98.50%at O:A ratio=2:1 after 4-stages of stripping.The enrichment of V remained in the solution was realized using P204 as extractant and 20%(mass)H_(2)SO_(4)as stripping reagent.The parameters of extraction/stripping process were investigated,using 10%P204+10%TBP+80%sulfonated kerosene as extractant,the V extraction efficiency reached 97.50%at O:A ratio=1:2after 4 stages of extraction.Using 20%H_(2)SO_(4)as the stripping reagent,the V stripping efficiency was 98.30%at an O:A ratio of 4:1 after five stage s of stripping.After the entire process,a high-purity VOSO_(4)and Na_(2)WO_(4)product solutions were obtained with V/W recovery efficiency 95.84%/98.50%,separately.This study examined a more effective and cleaner method for separating V/W/Na in Na_(2)WO_(4)/NaVO_(3)solution,which may serve as a reference for the separation and recovery of V/W/Na in waste SCR catalysts.展开更多
The recovery of ionic liquids(ILs)has attracted growing attention as an indispensable process in“green”industrial applications.Forward osmosis(FO)has proven to be a sustainable method for concentrating the very dilu...The recovery of ionic liquids(ILs)has attracted growing attention as an indispensable process in“green”industrial applications.Forward osmosis(FO)has proven to be a sustainable method for concentrating the very dilute aqueous solutions of ILs at ambient temperature,in which semi-permeable membranes play a vital role in determining the recovery efficiency.Herein,we use interfacial polymerization method to prepare thin-film composite membranes consisting of polyamide skin layer and electrospun nanofibrous substrate with tunable water permeability and IL selectivity for osmotic enrichment of imidazolium ILs from their dilute aqueous solutions through FO process.The resulting FO membrane shows a compact polyamide layer with a thickness of 30-200 nm,guranteeing a high selectivity to ILs and water.Meanwhile,the nanofibrous substrate with large and interconnect pores as well as low tortuosity,providing mechanical and permeable support for the composite membranes.IL structure influences the osmotic pressure difference as well as the interactions with polyamide layer of the membrane and thus determines the whole concentration process.First,the alkyl chain growth augments the osmosis pressure difference between the ILs solution and draw solution,resulting in an enhancement in driving force of water osmosis and IL enrichment.Moreover,alkyl length aggravates external concentration polarization caused by the enhanced adsorption of ILs onto the skin layer via electrostatic and alkyl-πinteractions.Meanwhile,such adsorbed ILs further enhance the IL retention but decrease the reverse salt diffusion.Therefore,imidazolium ILs with varied alkyl lengths are ultimately enriched with a 100-fold increase in concentration from their dilute aqueous solutions with high IL/NaCl rejection and low IL loss.Remarkably,the final concentration of IL with longest alkyl length reaches the highest(6.4 mol·L^(-1)).This work provides the insights in respect to material preparation and process amelioration for IL recovery with high scalability at mild conditions.展开更多
In practical engineering construction,multi-layered barriers containing geomembranes are extensively applied to retard the migration of pollutants.However,the associated analytical theory on pollutants diffusion still...In practical engineering construction,multi-layered barriers containing geomembranes are extensively applied to retard the migration of pollutants.However,the associated analytical theory on pollutants diffusion still needs to be further improved.In this work,general analytical solutions are derived for one-dimensional diffusion of degradable organic contaminant(DOC)in the multi-layered media containing geomembranes under a time-varying concentration boundary condition,where the variable substitution and separated variable approaches are employed.These analytical solutions with clear expressions can be used not only to study the diffusion behaviors of DOC in bottom and vertical composite barrier systems,but also to verify other complex numerical models.The proposed general analytical solutions are then fully validated via three comparative analyses,including comparisons with the experimental measurements,an existing analytical solution,and a finite-difference solution.Ultimately,the influences of different factors on the composite cutoff wall’s(CCW,which consists of two soil-bentonite layers and a geomembrane)service performance are investigated through a composite vertical barrier system as the application example.The findings obtained from this investigation can provide scientific guidance for the barrier performance evaluation and the engineering design of CCWs.This application example also exhibits the necessity and effectiveness of the developed analytical solutions.展开更多
Membrane/solution interface consists of a neutral concentration polai layer(CPL) and a charge layer(CL) under external electrical field, and the neutral CPL can be neglected under high frequency AC electrical field. T...Membrane/solution interface consists of a neutral concentration polai layer(CPL) and a charge layer(CL) under external electrical field, and the neutral CPL can be neglected under high frequency AC electrical field. The relationship of CL thickness e with electrolyte concentration C and fixed ion exchange sites density σ in membrane surface layer can be expressed as e展开更多
In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar perce...In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes.展开更多
Diabetic wounds present challenges in clinical management due to persistent inflammation caused by excessive exudate infiltration.Inspired by the gradient wettability of cactus thorn,this study has devised a biomimeti...Diabetic wounds present challenges in clinical management due to persistent inflammation caused by excessive exudate infiltration.Inspired by the gradient wettability of cactus thorn,this study has devised a biomimetic Janus nanofiber membrane as a water diode,which endows with gradient wettability and gradient pore size,offering sustainable unidirectional self-drainage and antibacterial properties for enhanced diabetic wound healing.The Janus membrane is fabricated by depositing a hydrophilic polyacrylonitrile/chlorin e6 layer with smaller pore sizes onto a hydrophobic poly(ε-caprolactone)with larger pore sizes,thereby generating a vertical gradient in both wettability and pore structure.The incorporation of chlorin e6 in the upper layer enables the utilization of external light energy to generate heat for evaporation and produce reactive oxygen species,achieving a high sterilization efficiency of 99%.Meanwhile,the gradient structure of the Janus membrane facilitates continuous antigravity exudate drainage at a rate of 0.95 g cm^(−2) h^(−1).This dual functionality of effective exudate drainage and sterilization significantly reduces inflammatory factors,allows the polarization of macrophages toward the M2 proliferative phenotype,enhances angiogenesis,and accelerates wound healing.Therefore,this study provides a groundbreaking bioinspired strategy for the development of advanced wound dressings tailored for diabetic wound regeneration.展开更多
AIM:To assess risk factors for epiretinal membranes(ERM)and examine their interactions in a nationally representative U.S.dataset.METHODS:Data from the 2005–2008 National Health and Nutrition Examination Survey(NHANE...AIM:To assess risk factors for epiretinal membranes(ERM)and examine their interactions in a nationally representative U.S.dataset.METHODS:Data from the 2005–2008 National Health and Nutrition Examination Survey(NHANES)were analyzed,a nationally representative U.S.dataset.ERM was identified via retinal imaging based on the presence of cellophane changes.Key predictors included age group,eye surgery history,and refractive error,with additional demographic and health-related covariates.Weighted univariate and multiple logistic regression models were used to assess associations and interaction effects between eye surgery and refractive error.RESULTS:Totally 3925 participants were analyzed.Older age,eye surgery,and refractive errors were significantly associated with ERM.Compared to those under 65y,the odds ratio(OR)for ERM was 3.08 for ages 65–75y(P=0.0014)and 4.76 for ages 75+years(P=0.0069).Eye surgery increased ERM risk(OR=3.48,P=0.0018).Moderate to high hyperopia and myopia were also associated with ERM(OR=2.65 and 1.80,respectively).A significant interaction between refractive error and eye surgery was observed(P<0.0001).Moderate to high myopia was associated with ERM only in those without eye surgery(OR=1.92,P=0.0443).Eye surgery was most strongly associated with ERM in the emmetropic group(OR=3.60,P=0.0027),followed by the moderate to high myopia group(OR=3.01,P=0.0031).CONCLUSION:ERM is significantly associated with aging,eye surgery,and refractive errors.The interaction between eye surgery and refractive error modifies ERM risk and highlights the importance of considering combined effects in clinical risk assessments.These findings may help guide individualized ERM risk assessment that may inform personalized approaches to ERM prevention and management.展开更多
The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR...The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR.However,their clinical translation is hindered by their inherently low immunogenicity,often requiring potent adjuvants and advanced delivery systems.Biomembrane nanostructures(e.g.,liposomes,exosomes,and cell membrane-derived nanostructures),characterized by superior biocompatibility,intrinsic targeting ability,and immune-modulating properties,could serve as versatile platforms that potentiate vaccine efficacy by increasing antigen stability,enabling codelivery of immunostimulants,and facilitating targeted delivery to lymphoid tissues/antigen-presenting cells.This intrinsic immunomodulation promotes robust humoral and cellular immune responses to combat bacteria.This review critically reviews(1)key biomembrane nanostructure classes for bacterial protein antigens,(2)design strategies leveraging biomembrane nanostructures to enhance humoral and cellular immune responses,(3)preclinical efficacy against diverse pathogens,and(4)translational challenges and prospects.Biomembrane nanostructure-driven approaches represent a paradigm shift in the development of next-generation bacterial protein vaccines against resistant infections.展开更多
An analytical model of a floating heaving box integrated with a vertical flexible porous membrane placed right next to the box applications to wave energy extraction and breakwater systems is developed under the reduc...An analytical model of a floating heaving box integrated with a vertical flexible porous membrane placed right next to the box applications to wave energy extraction and breakwater systems is developed under the reduced wave equation.The theoretical solutions for the heave radiating potential to the assigned physical model in the corresponding zones are attained by using the separation of variables approach along with the Fourier expansion.Applying the matching eigenfunction expansion technique and orthogonal conditions,the unknown coefficients that are involved in the radiated potentials are determined.The attained radiation potential allows the computation of hydrodynamic coefficients of the heaving buoy,Power Take-Off damping,and wave quantities.The accuracy of the analytical solution for the hydrodynamic coefficients is demonstrated for different oblique angles with varying numbers of terms in the series solution.The current analytical analysis findings are confirmed by existing published numerical boundary element method simulations.Several numerical results of the hydrodynamic coefficients,power capture,power take-off optimal damping,and transmission coefficients for numerous structural and physical aspects are conducted.It has been noted that the ideal power take-off damping increases as the angle of incidence rises,and the analysis suggests that the ability to capture waves is more effective in shallower waters compared to deeper ones.展开更多
Substrate and nutrient supply are essential for vegetable cultivation in greenhouse.The strategies for plant nutrient supply vary depending on the cultivation methods or substrate dosages employed.With the development...Substrate and nutrient supply are essential for vegetable cultivation in greenhouse.The strategies for plant nutrient supply vary depending on the cultivation methods or substrate dosages employed.With the development of mechanization,wide-row spacing substrate cultivation became an optimize mode of the greenhouse cucumber cultivation,aligning with the trend of intelligent agriculture.To determine the optimal nutrient solution supply amount(NS)and supply frequency(SF)for promoting the integrated growth of cucumber under wide-row spacing substrate cultivation,we explored the effects of substrate supply amount(SS),NS,and SF on cucumber yield,quality,and element utilization efficiency.A five-level quadratic orthogonal rotation combination design with three experimental factors(NS,SF,and SS)was implemented for 23 coupling treatments over three growing seasons,including spring(2022S and 2023S)and autumn(2022A).The technique for order preference by similarity to ideal solution(TOPSIS)combining weights based on game theory was applied to construct cucumber comprehensive growth evaluation model.Single and two experimental factors analyses revealed significant effects of single factors and the coupling of NS-SS,NS-SF and SS-SF on the integrated growth of cucumber for all three growing seasons.For the NS-SF-SS combination,the optimal parameters for comprehensive cucumber growth were determined as follows:levels of^(-1).68 for NS,-0.7 for SF,and^(-1).682 for SS in 2022A;-0.43 for NS,-0.06 for SF,and 0.34 for SS in 2022S;0.3 for NS,-0.02 for SF,and 0.04 for SS in 2023S.Furthermore,for SS ranges of 2.00-3.01,3.01-4.50,4.50-5.99,5.99-7.00(L·plant^(-1)),the corresponding NS and SF intervals maximizing cucumber integrated growth in spring were:0.28-0.30(L·plant^(-1))and 6(times·d^(-1)),0.26-0.30(L·plant^(-1))and 6(times·d^(-1)),0.25-0.30(L·plant^(-1))and 6(times·d^(-1)),0.23-0.30(L·plant^(-1))and 6(times·d^(-1)),respectively.With the same SS,the corresponding NS and SF intervals that maximized cucumber integrated growth in autumn were:0.10(L·plant^(-1))and 8(times·d^(-1)),0.18(L·plant^(-1))and 7(times·d^(-1)),0.30(L·plant^(-1))and 6(times·d^(-1)),0.49(L·plant^(-1))and 5(times·d^(-1)),respectively.The results provide a theoretical basis for solution management,and further in-depth research on cucumber cultivation.展开更多
It is very significant to recover rare earths （REs） from wet-process phosphoric acid, in terms of extraction rate and selectivity, the current carrier di（2-ethlhexly） phosphate （D2EHPA） out there is still inferi...It is very significant to recover rare earths （REs） from wet-process phosphoric acid, in terms of extraction rate and selectivity, the current carrier di（2-ethlhexly） phosphate （D2EHPA） out there is still inferior. Based on this question, our team modified D2EHPA to synthesize new extractants. This paper presents a comprehensive study on the extraction of rare earth ions （RE3＋） from phosphate leach solution using emulsion liquid membrane （ELM） in concentrated nitric acid medium. The ELM system is made up of （RO）2P（O）OPh-COOH as carrier, polyisocrotyl succinimide （T154） as surfactant, sulfonated kerosene as diluent, phosphoric acid （H3PO4） as stripping solution. Different chemical parameters such as type and concentration of carrier, surfactant, stripping solution, volume ratio of oil phase to internal phase, and volume ratio of emulsion ratio to external phase were analyzed. The extraction of RE^3＋ was evaluated by the yield of extraction. In addition, the demulsification process was also investigated. The proposed method of ELM using （RO）2P（O）OPh-COOH as carrier can he expected to provide an efficient, simplify operation, and facilitated method for extractine RE^3＋.展开更多
Concentrating sulfuric acid solution by vacuum membrane distillation with flat PEFE membrane is explored. The effects of sulfuric acid concentration, temperature of the feed, the vacuum degree of the vacuum side on th...Concentrating sulfuric acid solution by vacuum membrane distillation with flat PEFE membrane is explored. The effects of sulfuric acid concentration, temperature of the feed, the vacuum degree of the vacuum side on the flux of membrane distillation and the separation efficiency of acid are investigated. The results illustrate that the flux of the membrane distillation increases with the rise of feed temperature and the vacuum degree of the vacuum side, but it decreases with the rise of the sulfuric acid concentration of the feed. The separation efficiency of acid is correlated with the flux of membrane distillation; the separation efficiency of the acid can amount to 100% in the process, when operative conditions are properly controlled. It can also been obtained from the experiment that, compared with other methods of membrane distillation, the vacuum membrane distillation can obtain greater distillation flux.展开更多
Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding str...Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding strength in titanium/stainless steel laminated composites were investigated.Results indicate that the hardened layer reduces the interfacial bonding strength from over 261 MPa to less than 204 MPa.During the cold roll-bonding process,the hardened layer fractures,leading to the formation of multi-scale cracks that are difficult for the stainless steel to fill.This not only hinders the development of an interlocking interface but also leads to the presence of numerous microcracks and hardened blocks along the nearly straight interface,consequently weakening the interfacial bonding strength.In metals with high work hardening rates,the conventional approach of enhancing interface interlocking and improving interfacial bonding strength by using a surface-hardened layer becomes less effective.展开更多
The possibility of the recovery of hydrochloric acid from rare earth （RE） chloride solutions was first experimentally studied by batch vacuum membrane distillation （VMD）. The recovery by continuous VMD was also st...The possibility of the recovery of hydrochloric acid from rare earth （RE） chloride solutions was first experimentally studied by batch vacuum membrane distillation （VMD）. The recovery by continuous VMD was also studied to devise methods that enabled the operation of VMD setup in a stable condition as well as to increase the membrane-operating life The results indicated that HCl separation with RE by VMD was possible, and the recovery ratio of 80% could be achieved by batch VMD. In continuous VMD, when the temperature of circular solutions, circular rate, and downstream pressure was 62-63℃, 5.4 cm/s, and 9.33 kPa, respectively, the HCl concentration in circular solutions and the processing capacity per membrane area were obtained. The mathematical results were in accordance with the experimental ones.展开更多
Methyl isobutyl ketone(MIBK) is widely used as extraction agent in hydrometallurgy. As it has a definite solubility in water, so when using MIBK as extraction agent, there will be MIBK in stripping solutions inevitabl...Methyl isobutyl ketone(MIBK) is widely used as extraction agent in hydrometallurgy. As it has a definite solubility in water, so when using MIBK as extraction agent, there will be MIBK in stripping solutions inevitably, which not only pollutes working conditions, but also affects the quality of ultimate product. In order to remove MIBK from aqueous solutions, the means of flat vacuum membrane distillation(VMD) is studied in the paper. The area of the membrane used in the study is 0.02 m 2, the initial volume of feed is 2 L, each experiment was conducted over a time period of 60 120 min. The influences of the factors such as temperature(34.8 55.0 ℃); pressure in the permeate side(10.67 14.67 kPa) and feed flow rate(27.8 69.4 mL/s) were experimentally studied. Increasing the temperature or reducing the pressure in the permeate side results in a faster removal of MIBK; however there is a decrease in removal factor β , increasing the feed flow rate results in a faster removal of MIBK and an increase of removal factor β , especially in the range of lower flow rate. The study indicates that the aim of MIBK removal and recycle from dilute aqueous solutions can be achieved by VMD.展开更多
In this study, biologically inspired silk fibroin grafted polyacrylonitrile(SF-g-PAN) filtration membrane was prepared using ZnCl_2 aqueous solution as solvent, avoiding the use of organic solvents. Phase inversion oc...In this study, biologically inspired silk fibroin grafted polyacrylonitrile(SF-g-PAN) filtration membrane was prepared using ZnCl_2 aqueous solution as solvent, avoiding the use of organic solvents. Phase inversion occurred when Zn^(2+)and Cl-ions gradually diffused into water, creating a well-connected ion channel network and the SF-g-PAN filtration membrane was obtained. The membranes were observed by SEM and 3D ultra-depth microscope. The hydrophilic property, pore size distribution and dye rejection of the membrane were investigated. Results showed that the membrane has no finger hole formation because ZnCl_2 aqueous solution has a lower curing rate parameter compared with organic solvents. SF-gPAN membrane possessed good anti-fouling properties and pH sensitivity. The pore size distribution of the SF-g-PAN membrane was 0.25–1.04 nm. The rejection of direct yellow 27(Mw = 662.6) and amaranth(Mw = 604.5) was 96.51% and 30.63%, with the flux of 72.32 L m^(-2) h^(-1) and 73.83 L m^(-2) h^(-1) respectively at0.1 MPa. The SF-g-PAN membrane has a wide range of applications prospect in fine separation, dye desalination, waste water treatment and biomedical fields.展开更多
Mg–Al–Fe layered double hydroxides（LDHs） were exfoliated and incorporated in polyether sulfone membranes for the removal of phosphate and fluoride for the first time. The exfoliation methods, coagulation bath, LDH...Mg–Al–Fe layered double hydroxides（LDHs） were exfoliated and incorporated in polyether sulfone membranes for the removal of phosphate and fluoride for the first time. The exfoliation methods, coagulation bath, LDH amount, interfering ions, adsorption isotherm,desorption and reuse of the membranes were investigated. It was found that LDHs could be quickly exfoliated in formamide/N,N-dimethylformamide（DMF） solvent mixtures with sodium carboxymethyl cellulose as a stabilizer. The membranes displayed much higher adsorption capacity for phosphate（5.61 mg/g） and faster adsorption rate than the unexfoliated materials. With increased DMF content in the coagulation bath, the static and dynamic adsorption capacity rose. Interference from Cl-and SO4^（2-）（50 mg/L） on adsorption of phosphates was not apparent. The membranes displayed excellent reusability in dynamic adsorption/desorption. The membranes also showed high adsorption capacity for fluorides（1.61 mg/g）.展开更多
Microporous chitosan （CS） membranes were directly prepared by extraction of poly（ethylene glycol） （PEG） from CS/PEG blend membrane and were examined for iron and manganese ions removal from aqueous solutions. Th...Microporous chitosan （CS） membranes were directly prepared by extraction of poly（ethylene glycol） （PEG） from CS/PEG blend membrane and were examined for iron and manganese ions removal from aqueous solutions. The different variables affecting the adsorption capacity of the membranes such as contact time, pH of the sorption medium, and initial metal ion concentration in the feed solution were investigated on a batch adsorption basis. The affinity of CS/PEG blend membrane to adsorb Fe（II） ions is higher than that of Mn（II） ions, with adsorption equilibrium achieved after 60 min for Fe（II） and Mn（II） ions. By increasing CS]PEG ratio in the blend membrane the adsorption capacity of metal ions increased. Among all parameters, pH has the most significant effect on the adsorption capacity, particularly in the range of 2.9-5.9. The increase in CS/PEG ratio was found to enhance the adsorption capacity of the membranes. The effects of initial concentration of metal ions on the extent of metal ions removal were investigated in detail. The experimental data were better fitted to Freundlich equation than Langmuir. In addition, it was found that the iron and manganese ions adsorbed on the membranes can be effectively desorbed in 0.1 mol/L HCl solution （up to 98% desorption efficiency） and the blend membranes can be reused almost without loss of the adsorption capacity for iron and manganese ions.展开更多
By using membrane dispersion micro-extractor, Ce（IIl） solvent extraction experiments were conducted. Cerium chloride solution with certain acidity was used as aqueous phase and 2-ethylhexyl phosphoric acid-2-ethylhe...By using membrane dispersion micro-extractor, Ce（IIl） solvent extraction experiments were conducted. Cerium chloride solution with certain acidity was used as aqueous phase and 2-ethylhexyl phosphoric acid-2-ethylhexyl ester （EHEHPA） kerosene solution as organic phase. The effects of system physicochemical properties and operational conditions, such as initial EHEHPA concentration, initial aqueous acidity, total flow rate and continuous phase flow rate, etc., on the extraction efficiency and the overall volume mass transfer coefficient were evaluated. As the total flow rate increased fi＇om 20 to 160 mL/min, the overall volume mass transfer coefficient was enhanced from 0.1 to 0.54 S1. Under the optimal conditions, the Ce（III） extraction efficiency could reach 99.92% in 2.98 s. A mathematical model was set up to predict the overall volume mass transfer coefficient, and the calculation results agreed well with the experimental results, most relative error was within ＋10%.展开更多
Treating acid gases contained in natural gas by MDEA is used widely. But the efficiency of regeneration of the MDEA solution limited the development of this technology. An optimal temperature is necessary for regenera...Treating acid gases contained in natural gas by MDEA is used widely. But the efficiency of regeneration of the MDEA solution limited the development of this technology. An optimal temperature is necessary for regeneration of the MDEA solution using membrane distillation. The experiment results showed that the regeneration rate of MDEA rose with an increasing temperature. But the rate increased slowly after the regeneration temperature arrived at a certain value. This study can confirm that regeneration of the MDEA solution using membrane distillation is feasible. This technology provides more advantages as compared to conventional regeneration process.展开更多
基金the support the National Natural Science Foundation of China(5210440)S&T Program of Hebei(23311501D)Program of HBIS Group under HG2023222。
文摘In this study,a cleaner method for separation and recovery of V/W/Na in waste selective catalytic reduction(SCR)catalyst alkaline leaching solution was proposed.The method involved membrane electrolysis followed by ion morphology pretreatme nt and solvent extraction.An acidic V(Ⅴ)/W(Ⅵ)solution was obtained using the me mbrane electrolysis method without adding any other chemical reagents.In addition,Na was recovered in the form of NaOH by product,avoiding the generation of Na containing wastewater.The electrolysis parameters were investigated,the lowest power consumption of 3063 kW·h·t^(-1)NaOH was obtained at a current density of 125 A·m^(-2)and an initial NaOH concentration of 2 mol·L^(-1).After electrolysis,oxalic acid was added to the acidic V/W containing solution,converting V(Ⅴ)negative ion to V(Ⅳ)positive ion.Since W(Ⅵ)ion state remained in negative form,the generation of heteropolyacid ions(W_(x)V_(y)O_(z)^(n-))was prevented.It was found that under the condition of oxalic acid addition/theoretical consumption 1.2 and reaction temperature 75℃,100%V(Ⅴ)was co nverted to V(Ⅳ4).Using 10%N263+10%noctanol+80%sulfonated kerosene as extractant,the highest W(Ⅵ)/V(Ⅳ)separation coefficient of 7559.76was obtained at pH=1.8,O:A ratio=1:1 and extraction time 15 min.With 2 mol·L^(-1)NaOH as stripping reagent,the W stripping efficiency reached 98.50%at O:A ratio=2:1 after 4-stages of stripping.The enrichment of V remained in the solution was realized using P204 as extractant and 20%(mass)H_(2)SO_(4)as stripping reagent.The parameters of extraction/stripping process were investigated,using 10%P204+10%TBP+80%sulfonated kerosene as extractant,the V extraction efficiency reached 97.50%at O:A ratio=1:2after 4 stages of extraction.Using 20%H_(2)SO_(4)as the stripping reagent,the V stripping efficiency was 98.30%at an O:A ratio of 4:1 after five stage s of stripping.After the entire process,a high-purity VOSO_(4)and Na_(2)WO_(4)product solutions were obtained with V/W recovery efficiency 95.84%/98.50%,separately.This study examined a more effective and cleaner method for separating V/W/Na in Na_(2)WO_(4)/NaVO_(3)solution,which may serve as a reference for the separation and recovery of V/W/Na in waste SCR catalysts.
基金supported by the National Natural Science Foundation of China(No.52173095)the MOE Key Laboratory of Macromolecular Synthesis and Functionalization,Zhejiang University(No.2023MSF05)。
文摘The recovery of ionic liquids(ILs)has attracted growing attention as an indispensable process in“green”industrial applications.Forward osmosis(FO)has proven to be a sustainable method for concentrating the very dilute aqueous solutions of ILs at ambient temperature,in which semi-permeable membranes play a vital role in determining the recovery efficiency.Herein,we use interfacial polymerization method to prepare thin-film composite membranes consisting of polyamide skin layer and electrospun nanofibrous substrate with tunable water permeability and IL selectivity for osmotic enrichment of imidazolium ILs from their dilute aqueous solutions through FO process.The resulting FO membrane shows a compact polyamide layer with a thickness of 30-200 nm,guranteeing a high selectivity to ILs and water.Meanwhile,the nanofibrous substrate with large and interconnect pores as well as low tortuosity,providing mechanical and permeable support for the composite membranes.IL structure influences the osmotic pressure difference as well as the interactions with polyamide layer of the membrane and thus determines the whole concentration process.First,the alkyl chain growth augments the osmosis pressure difference between the ILs solution and draw solution,resulting in an enhancement in driving force of water osmosis and IL enrichment.Moreover,alkyl length aggravates external concentration polarization caused by the enhanced adsorption of ILs onto the skin layer via electrostatic and alkyl-πinteractions.Meanwhile,such adsorbed ILs further enhance the IL retention but decrease the reverse salt diffusion.Therefore,imidazolium ILs with varied alkyl lengths are ultimately enriched with a 100-fold increase in concentration from their dilute aqueous solutions with high IL/NaCl rejection and low IL loss.Remarkably,the final concentration of IL with longest alkyl length reaches the highest(6.4 mol·L^(-1)).This work provides the insights in respect to material preparation and process amelioration for IL recovery with high scalability at mild conditions.
基金Project(2023YFC3707800)supported by the National Key Research and Development Program of China。
文摘In practical engineering construction,multi-layered barriers containing geomembranes are extensively applied to retard the migration of pollutants.However,the associated analytical theory on pollutants diffusion still needs to be further improved.In this work,general analytical solutions are derived for one-dimensional diffusion of degradable organic contaminant(DOC)in the multi-layered media containing geomembranes under a time-varying concentration boundary condition,where the variable substitution and separated variable approaches are employed.These analytical solutions with clear expressions can be used not only to study the diffusion behaviors of DOC in bottom and vertical composite barrier systems,but also to verify other complex numerical models.The proposed general analytical solutions are then fully validated via three comparative analyses,including comparisons with the experimental measurements,an existing analytical solution,and a finite-difference solution.Ultimately,the influences of different factors on the composite cutoff wall’s(CCW,which consists of two soil-bentonite layers and a geomembrane)service performance are investigated through a composite vertical barrier system as the application example.The findings obtained from this investigation can provide scientific guidance for the barrier performance evaluation and the engineering design of CCWs.This application example also exhibits the necessity and effectiveness of the developed analytical solutions.
基金Project(02-09-01) supported by Panzhihua Iron and Steel Corporation,China
文摘Membrane/solution interface consists of a neutral concentration polai layer(CPL) and a charge layer(CL) under external electrical field, and the neutral CPL can be neglected under high frequency AC electrical field. The relationship of CL thickness e with electrolyte concentration C and fixed ion exchange sites density σ in membrane surface layer can be expressed as e
基金Supported by the Doctoral Research Start-up Project of Yuncheng University(YQ-2023067)Project of Shanxi Natural Science Foundation(202303021211189)+1 种基金Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Provinces(20220036)Shanxi ProvinceIntelligent Optoelectronic Sensing Application Technology Innovation Center and Shanxi Province Optoelectronic Information Science and TechnologyLaboratory,Yuncheng University.
文摘In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes.
基金All animal experiments were performed under the protocols approved by the Ethical Committee for Animal Care of Donghua University(DHUEC-NSFC-2019-20)financially supported by the National Key Research and Development Program of China(2021YFA1201304)+3 种基金the National Natural Science Foundation of China(52503082),China Postdoctoral Science Foundation(2024M750402)Postdoctoral Fellowship Program of CPSF(GZC20230419)Shanghai Anticancer Association EYAS PROJECT(SACA-CY23C05)The Fundamental Research Funds for the Central Universities(2232023D-03,2232024Y-01).
文摘Diabetic wounds present challenges in clinical management due to persistent inflammation caused by excessive exudate infiltration.Inspired by the gradient wettability of cactus thorn,this study has devised a biomimetic Janus nanofiber membrane as a water diode,which endows with gradient wettability and gradient pore size,offering sustainable unidirectional self-drainage and antibacterial properties for enhanced diabetic wound healing.The Janus membrane is fabricated by depositing a hydrophilic polyacrylonitrile/chlorin e6 layer with smaller pore sizes onto a hydrophobic poly(ε-caprolactone)with larger pore sizes,thereby generating a vertical gradient in both wettability and pore structure.The incorporation of chlorin e6 in the upper layer enables the utilization of external light energy to generate heat for evaporation and produce reactive oxygen species,achieving a high sterilization efficiency of 99%.Meanwhile,the gradient structure of the Janus membrane facilitates continuous antigravity exudate drainage at a rate of 0.95 g cm^(−2) h^(−1).This dual functionality of effective exudate drainage and sterilization significantly reduces inflammatory factors,allows the polarization of macrophages toward the M2 proliferative phenotype,enhances angiogenesis,and accelerates wound healing.Therefore,this study provides a groundbreaking bioinspired strategy for the development of advanced wound dressings tailored for diabetic wound regeneration.
基金Supported by Chengdu Municipal Science and Technology Bureau Key R&D Support Program(No.2023-YF09-00041-SN)。
文摘AIM:To assess risk factors for epiretinal membranes(ERM)and examine their interactions in a nationally representative U.S.dataset.METHODS:Data from the 2005–2008 National Health and Nutrition Examination Survey(NHANES)were analyzed,a nationally representative U.S.dataset.ERM was identified via retinal imaging based on the presence of cellophane changes.Key predictors included age group,eye surgery history,and refractive error,with additional demographic and health-related covariates.Weighted univariate and multiple logistic regression models were used to assess associations and interaction effects between eye surgery and refractive error.RESULTS:Totally 3925 participants were analyzed.Older age,eye surgery,and refractive errors were significantly associated with ERM.Compared to those under 65y,the odds ratio(OR)for ERM was 3.08 for ages 65–75y(P=0.0014)and 4.76 for ages 75+years(P=0.0069).Eye surgery increased ERM risk(OR=3.48,P=0.0018).Moderate to high hyperopia and myopia were also associated with ERM(OR=2.65 and 1.80,respectively).A significant interaction between refractive error and eye surgery was observed(P<0.0001).Moderate to high myopia was associated with ERM only in those without eye surgery(OR=1.92,P=0.0443).Eye surgery was most strongly associated with ERM in the emmetropic group(OR=3.60,P=0.0027),followed by the moderate to high myopia group(OR=3.01,P=0.0031).CONCLUSION:ERM is significantly associated with aging,eye surgery,and refractive errors.The interaction between eye surgery and refractive error modifies ERM risk and highlights the importance of considering combined effects in clinical risk assessments.These findings may help guide individualized ERM risk assessment that may inform personalized approaches to ERM prevention and management.
基金the National Natural Science Foundation of China(82573571)the Shanghai 2025 Basic Research Plan Natural Science Foundation(25ZR1401393)the First Batch of Open Topics of the Shanghai Key Laboratory of Nautical Medicine and Translation of Drugs and Medical Devices(2025QN13)。
文摘The global burden of bacterial infections,exacerbated by antimicrobial resistance(AMR),necessitates innovative strategies.Bacterial protein vaccines offer promise by eliciting targeted immunity while circumventing AMR.However,their clinical translation is hindered by their inherently low immunogenicity,often requiring potent adjuvants and advanced delivery systems.Biomembrane nanostructures(e.g.,liposomes,exosomes,and cell membrane-derived nanostructures),characterized by superior biocompatibility,intrinsic targeting ability,and immune-modulating properties,could serve as versatile platforms that potentiate vaccine efficacy by increasing antigen stability,enabling codelivery of immunostimulants,and facilitating targeted delivery to lymphoid tissues/antigen-presenting cells.This intrinsic immunomodulation promotes robust humoral and cellular immune responses to combat bacteria.This review critically reviews(1)key biomembrane nanostructure classes for bacterial protein antigens,(2)design strategies leveraging biomembrane nanostructures to enhance humoral and cellular immune responses,(3)preclinical efficacy against diverse pathogens,and(4)translational challenges and prospects.Biomembrane nanostructure-driven approaches represent a paradigm shift in the development of next-generation bacterial protein vaccines against resistant infections.
基金Open access funding provided by FCT|FCCN(b-on)the Strategic Research Plan of the Centre for Marine Technology and Ocean Engineering(CENTEC),which is financed by the Portuguese Foundation for Science and Technology(Fundação para a Ciência e Tecnologia-FCT)under contract UIDB/UIDP/00134/2020.
文摘An analytical model of a floating heaving box integrated with a vertical flexible porous membrane placed right next to the box applications to wave energy extraction and breakwater systems is developed under the reduced wave equation.The theoretical solutions for the heave radiating potential to the assigned physical model in the corresponding zones are attained by using the separation of variables approach along with the Fourier expansion.Applying the matching eigenfunction expansion technique and orthogonal conditions,the unknown coefficients that are involved in the radiated potentials are determined.The attained radiation potential allows the computation of hydrodynamic coefficients of the heaving buoy,Power Take-Off damping,and wave quantities.The accuracy of the analytical solution for the hydrodynamic coefficients is demonstrated for different oblique angles with varying numbers of terms in the series solution.The current analytical analysis findings are confirmed by existing published numerical boundary element method simulations.Several numerical results of the hydrodynamic coefficients,power capture,power take-off optimal damping,and transmission coefficients for numerous structural and physical aspects are conducted.It has been noted that the ideal power take-off damping increases as the angle of incidence rises,and the analysis suggests that the ability to capture waves is more effective in shallower waters compared to deeper ones.
基金supported by the China Agriculture Research System(Grant No.CARS-23-D06)the Key Research and Development Program of Shaanxi Province(Grant Nos.2024NC2-GJHX-29 and 2024NC-ZDCYL-05-08)Shaanxi Agricultural Collaborative Innovation and Extension Alliance Project(Grant No.LMZD202202).
文摘Substrate and nutrient supply are essential for vegetable cultivation in greenhouse.The strategies for plant nutrient supply vary depending on the cultivation methods or substrate dosages employed.With the development of mechanization,wide-row spacing substrate cultivation became an optimize mode of the greenhouse cucumber cultivation,aligning with the trend of intelligent agriculture.To determine the optimal nutrient solution supply amount(NS)and supply frequency(SF)for promoting the integrated growth of cucumber under wide-row spacing substrate cultivation,we explored the effects of substrate supply amount(SS),NS,and SF on cucumber yield,quality,and element utilization efficiency.A five-level quadratic orthogonal rotation combination design with three experimental factors(NS,SF,and SS)was implemented for 23 coupling treatments over three growing seasons,including spring(2022S and 2023S)and autumn(2022A).The technique for order preference by similarity to ideal solution(TOPSIS)combining weights based on game theory was applied to construct cucumber comprehensive growth evaluation model.Single and two experimental factors analyses revealed significant effects of single factors and the coupling of NS-SS,NS-SF and SS-SF on the integrated growth of cucumber for all three growing seasons.For the NS-SF-SS combination,the optimal parameters for comprehensive cucumber growth were determined as follows:levels of^(-1).68 for NS,-0.7 for SF,and^(-1).682 for SS in 2022A;-0.43 for NS,-0.06 for SF,and 0.34 for SS in 2022S;0.3 for NS,-0.02 for SF,and 0.04 for SS in 2023S.Furthermore,for SS ranges of 2.00-3.01,3.01-4.50,4.50-5.99,5.99-7.00(L·plant^(-1)),the corresponding NS and SF intervals maximizing cucumber integrated growth in spring were:0.28-0.30(L·plant^(-1))and 6(times·d^(-1)),0.26-0.30(L·plant^(-1))and 6(times·d^(-1)),0.25-0.30(L·plant^(-1))and 6(times·d^(-1)),0.23-0.30(L·plant^(-1))and 6(times·d^(-1)),respectively.With the same SS,the corresponding NS and SF intervals that maximized cucumber integrated growth in autumn were:0.10(L·plant^(-1))and 8(times·d^(-1)),0.18(L·plant^(-1))and 7(times·d^(-1)),0.30(L·plant^(-1))and 6(times·d^(-1)),0.49(L·plant^(-1))and 5(times·d^(-1)),respectively.The results provide a theoretical basis for solution management,and further in-depth research on cucumber cultivation.
基金Project supported by National Natural Science Foundation of China(21461005)"Top Hundred Talents" Program of Science and Technology Development of Guizhou Province([2016]5658)
文摘It is very significant to recover rare earths （REs） from wet-process phosphoric acid, in terms of extraction rate and selectivity, the current carrier di（2-ethlhexly） phosphate （D2EHPA） out there is still inferior. Based on this question, our team modified D2EHPA to synthesize new extractants. This paper presents a comprehensive study on the extraction of rare earth ions （RE3＋） from phosphate leach solution using emulsion liquid membrane （ELM） in concentrated nitric acid medium. The ELM system is made up of （RO）2P（O）OPh-COOH as carrier, polyisocrotyl succinimide （T154） as surfactant, sulfonated kerosene as diluent, phosphoric acid （H3PO4） as stripping solution. Different chemical parameters such as type and concentration of carrier, surfactant, stripping solution, volume ratio of oil phase to internal phase, and volume ratio of emulsion ratio to external phase were analyzed. The extraction of RE^3＋ was evaluated by the yield of extraction. In addition, the demulsification process was also investigated. The proposed method of ELM using （RO）2P（O）OPh-COOH as carrier can he expected to provide an efficient, simplify operation, and facilitated method for extractine RE^3＋.
文摘Concentrating sulfuric acid solution by vacuum membrane distillation with flat PEFE membrane is explored. The effects of sulfuric acid concentration, temperature of the feed, the vacuum degree of the vacuum side on the flux of membrane distillation and the separation efficiency of acid are investigated. The results illustrate that the flux of the membrane distillation increases with the rise of feed temperature and the vacuum degree of the vacuum side, but it decreases with the rise of the sulfuric acid concentration of the feed. The separation efficiency of acid is correlated with the flux of membrane distillation; the separation efficiency of the acid can amount to 100% in the process, when operative conditions are properly controlled. It can also been obtained from the experiment that, compared with other methods of membrane distillation, the vacuum membrane distillation can obtain greater distillation flux.
基金supported by the National Key R&D Program of China (No. 2018YFA0707300)the National Natural Science Foundation of China (No. 52374376)the Introduction Plan for High end Foreign Experts, China (No. G2023105001L)。
文摘Titanium plates with a Ti−O solid solution surface-hardened layer were cold roll-bonded with 304 stainless steel plates with high work hardening rates.The evolution and mechanisms affecting the interfacial bonding strength in titanium/stainless steel laminated composites were investigated.Results indicate that the hardened layer reduces the interfacial bonding strength from over 261 MPa to less than 204 MPa.During the cold roll-bonding process,the hardened layer fractures,leading to the formation of multi-scale cracks that are difficult for the stainless steel to fill.This not only hinders the development of an interlocking interface but also leads to the presence of numerous microcracks and hardened blocks along the nearly straight interface,consequently weakening the interfacial bonding strength.In metals with high work hardening rates,the conventional approach of enhancing interface interlocking and improving interfacial bonding strength by using a surface-hardened layer becomes less effective.
文摘The possibility of the recovery of hydrochloric acid from rare earth （RE） chloride solutions was first experimentally studied by batch vacuum membrane distillation （VMD）. The recovery by continuous VMD was also studied to devise methods that enabled the operation of VMD setup in a stable condition as well as to increase the membrane-operating life The results indicated that HCl separation with RE by VMD was possible, and the recovery ratio of 80% could be achieved by batch VMD. In continuous VMD, when the temperature of circular solutions, circular rate, and downstream pressure was 62-63℃, 5.4 cm/s, and 9.33 kPa, respectively, the HCl concentration in circular solutions and the processing capacity per membrane area were obtained. The mathematical results were in accordance with the experimental ones.
文摘Methyl isobutyl ketone(MIBK) is widely used as extraction agent in hydrometallurgy. As it has a definite solubility in water, so when using MIBK as extraction agent, there will be MIBK in stripping solutions inevitably, which not only pollutes working conditions, but also affects the quality of ultimate product. In order to remove MIBK from aqueous solutions, the means of flat vacuum membrane distillation(VMD) is studied in the paper. The area of the membrane used in the study is 0.02 m 2, the initial volume of feed is 2 L, each experiment was conducted over a time period of 60 120 min. The influences of the factors such as temperature(34.8 55.0 ℃); pressure in the permeate side(10.67 14.67 kPa) and feed flow rate(27.8 69.4 mL/s) were experimentally studied. Increasing the temperature or reducing the pressure in the permeate side results in a faster removal of MIBK; however there is a decrease in removal factor β , increasing the feed flow rate results in a faster removal of MIBK and an increase of removal factor β , especially in the range of lower flow rate. The study indicates that the aim of MIBK removal and recycle from dilute aqueous solutions can be achieved by VMD.
基金supported by the National Natural Science Foundation of China (Nos. 51678409, 145 708407, 21476172)Tianjin Science Technology Research Funds of China (Nos. 16JCZDJC37500, 15JCZDJC38300)+1 种基金Program for Innovative Research Team in University of Tianjin (No. TD13-5042)Science Foundation for the Youth Teachers of Peking Union Medical College (No. 2014ZLGC0754)
文摘In this study, biologically inspired silk fibroin grafted polyacrylonitrile(SF-g-PAN) filtration membrane was prepared using ZnCl_2 aqueous solution as solvent, avoiding the use of organic solvents. Phase inversion occurred when Zn^(2+)and Cl-ions gradually diffused into water, creating a well-connected ion channel network and the SF-g-PAN filtration membrane was obtained. The membranes were observed by SEM and 3D ultra-depth microscope. The hydrophilic property, pore size distribution and dye rejection of the membrane were investigated. Results showed that the membrane has no finger hole formation because ZnCl_2 aqueous solution has a lower curing rate parameter compared with organic solvents. SF-gPAN membrane possessed good anti-fouling properties and pH sensitivity. The pore size distribution of the SF-g-PAN membrane was 0.25–1.04 nm. The rejection of direct yellow 27(Mw = 662.6) and amaranth(Mw = 604.5) was 96.51% and 30.63%, with the flux of 72.32 L m^(-2) h^(-1) and 73.83 L m^(-2) h^(-1) respectively at0.1 MPa. The SF-g-PAN membrane has a wide range of applications prospect in fine separation, dye desalination, waste water treatment and biomedical fields.
基金supported by the National Natural Science Foundation of China and Qinghai Qaidam Saline Lake Chemical Science Research Joint Fund (No. U1607109)
文摘Mg–Al–Fe layered double hydroxides（LDHs） were exfoliated and incorporated in polyether sulfone membranes for the removal of phosphate and fluoride for the first time. The exfoliation methods, coagulation bath, LDH amount, interfering ions, adsorption isotherm,desorption and reuse of the membranes were investigated. It was found that LDHs could be quickly exfoliated in formamide/N,N-dimethylformamide（DMF） solvent mixtures with sodium carboxymethyl cellulose as a stabilizer. The membranes displayed much higher adsorption capacity for phosphate（5.61 mg/g） and faster adsorption rate than the unexfoliated materials. With increased DMF content in the coagulation bath, the static and dynamic adsorption capacity rose. Interference from Cl-and SO4^（2-）（50 mg/L） on adsorption of phosphates was not apparent. The membranes displayed excellent reusability in dynamic adsorption/desorption. The membranes also showed high adsorption capacity for fluorides（1.61 mg/g）.
基金supported by the Housing & Building National Research Centre in EgyptCentral Metallurgical R & D Institute (CMRDI)
文摘Microporous chitosan （CS） membranes were directly prepared by extraction of poly（ethylene glycol） （PEG） from CS/PEG blend membrane and were examined for iron and manganese ions removal from aqueous solutions. The different variables affecting the adsorption capacity of the membranes such as contact time, pH of the sorption medium, and initial metal ion concentration in the feed solution were investigated on a batch adsorption basis. The affinity of CS/PEG blend membrane to adsorb Fe（II） ions is higher than that of Mn（II） ions, with adsorption equilibrium achieved after 60 min for Fe（II） and Mn（II） ions. By increasing CS]PEG ratio in the blend membrane the adsorption capacity of metal ions increased. Among all parameters, pH has the most significant effect on the adsorption capacity, particularly in the range of 2.9-5.9. The increase in CS/PEG ratio was found to enhance the adsorption capacity of the membranes. The effects of initial concentration of metal ions on the extent of metal ions removal were investigated in detail. The experimental data were better fitted to Freundlich equation than Langmuir. In addition, it was found that the iron and manganese ions adsorbed on the membranes can be effectively desorbed in 0.1 mol/L HCl solution （up to 98% desorption efficiency） and the blend membranes can be reused almost without loss of the adsorption capacity for iron and manganese ions.
基金Project supported by the National Basic Research Program of China(2012CBA01203)the National Natural Science Foundation of China(90210034,20221603)
文摘By using membrane dispersion micro-extractor, Ce（IIl） solvent extraction experiments were conducted. Cerium chloride solution with certain acidity was used as aqueous phase and 2-ethylhexyl phosphoric acid-2-ethylhexyl ester （EHEHPA） kerosene solution as organic phase. The effects of system physicochemical properties and operational conditions, such as initial EHEHPA concentration, initial aqueous acidity, total flow rate and continuous phase flow rate, etc., on the extraction efficiency and the overall volume mass transfer coefficient were evaluated. As the total flow rate increased fi＇om 20 to 160 mL/min, the overall volume mass transfer coefficient was enhanced from 0.1 to 0.54 S1. Under the optimal conditions, the Ce（III） extraction efficiency could reach 99.92% in 2.98 s. A mathematical model was set up to predict the overall volume mass transfer coefficient, and the calculation results agreed well with the experimental results, most relative error was within ＋10%.
文摘Treating acid gases contained in natural gas by MDEA is used widely. But the efficiency of regeneration of the MDEA solution limited the development of this technology. An optimal temperature is necessary for regeneration of the MDEA solution using membrane distillation. The experiment results showed that the regeneration rate of MDEA rose with an increasing temperature. But the rate increased slowly after the regeneration temperature arrived at a certain value. This study can confirm that regeneration of the MDEA solution using membrane distillation is feasible. This technology provides more advantages as compared to conventional regeneration process.
