The research on the adsorption equilibria,kinetics,and increase in process temperature of the volatile organic compound(VOC)adsorption in porous materials ensures safe production,thereby reducing production costs and ...The research on the adsorption equilibria,kinetics,and increase in process temperature of the volatile organic compound(VOC)adsorption in porous materials ensures safe production,thereby reducing production costs and improving separation efficiency.Therefore,it is critical in predicting the entire adsorption process based on minimal or no experimental input of the adsorbate and adsorbent.We discuss,in this review,the factors that affect the adsorption performance of VOCs in activated carbons,including the adsorption equilibrium,adsorption kinetics,and exotherm during adsorption.Subsequently,the existing prediction models are summarized and compared concerning the adsorption equilibrium,adsorption kinetics,and exothermic process of adsorption.We then propose a new prediction model based on intermolecular interaction and provide an outlook toward the design and manipulation of efficient adsorbents for the VOC system.展开更多
How to reduce flow resistance of nano-confined fluids to achieve a high flux is a new challenge for modern chemical engineering applications, such as membrane separation and nanofluidic devices. Traditional models are...How to reduce flow resistance of nano-confined fluids to achieve a high flux is a new challenge for modern chemical engineering applications, such as membrane separation and nanofluidic devices. Traditional models are inapplicable to explain the significant differences in the flow resistance of different liquid–solid systems.On the other hand, friction reduction in liquid nano-lubrication has received considerable attention during the past decades. Both fields are exposed to a common scientific issue regarding friction reduction during liquid–solid relative motion at nanoscale. A promising approach to control the flow resistance of nano-confined fluids is to reference the factors affecting liquid nano-lubrication. In this review, two concepts of the friction coefficient derived from fluid flow and tribology were discussed to reveal their intrinsic relations. Recent progress on low or ultra-low friction coefficients in liquid nano-lubrication was summarized based on two situations. Finally, a new strategy was introduced to study the friction coefficient based on analyzing the intermolecular interactions through an atomic force microscope(AFM), which is a cutting-point to build a new model to study flowresistance at nanoscale.展开更多
Monolayer molybdenum disulfide(MoS2) is a novel two-dimensional material that exhibits potential application in lubrication technology. In this work, molecular dynamics was used to investigate the lubrication behaviou...Monolayer molybdenum disulfide(MoS2) is a novel two-dimensional material that exhibits potential application in lubrication technology. In this work, molecular dynamics was used to investigate the lubrication behaviour of different polar fluid molecules(i.e., water, methanol and decane) confined in monolayer Mo S2 nanoslits. The pore width effect(i.e., 1.2, 1.6 and 2.0 nm) was also evaluated. Results revealed that decane molecules exhibited good lubricating performance compared to the other two kinds of molecules. The friction coefficient followed the order of decane b methanol b water, and decreased evidently as the slit width increased, except for decane. Analysis of the spatial distribution and mobility of different confined fluid molecules showed that a solid-like layer was formed near the slit wall. This phenomenon led to the extra low friction coefficient of confined decane molecules.展开更多
In modern chemical engineering processes, solid interface involvement is the most important component of process intensification techniques, such as nanoporous membrane separation and heterogeneous catalysis. The fund...In modern chemical engineering processes, solid interface involvement is the most important component of process intensification techniques, such as nanoporous membrane separation and heterogeneous catalysis. The fundamental mechanism underlying interfacial transport remains incompletely understood given the complexity of heterogeneous interfacial molecular interactions and the high nonideality of the fluid involved. Thus, understanding the effects of interface-induced fluid microstructures on flow resistance is the first step in further understanding interfacial transport. Molecular simulation has become an indispensable method for the investigation of fluid microstructure and flow resistance. Here, we reviewed the recent research progress of our group and the latest relevant works to elucidate the contribution of interface-induced fluid microstructures to flow resistance.We specifically focused on water, ionic aqueous solutions, and alcohol–water mixtures given the ubiquity of these fluid systems in modern chemical engineering processes. We discussed the effects of the interfaceinduced hydrogen bond networks of water molecules, the ionic hydration of ionic aqueous solutions, and the spatial distributions of alcohol and alcohol–water mixtures on flow resistance on the basis of the distinctive characteristics of different fluid systems.展开更多
In modern chemical engineering processes, the involvement of solid/fluid interface is the most important component of process intensification techniques, such as confined membrane separation and catalysis. In the revi...In modern chemical engineering processes, the involvement of solid/fluid interface is the most important component of process intensification techniques, such as confined membrane separation and catalysis. In the review, we summarized the research progress of the latest theoretical and experimental works to elucidate the contribution of interface to the fluid properties and structures at nano-and micro-scale. We mainly focused on water, alcohol aqueous solution, and ionic liquids, because they are classical systems in interfacial science and/or widely involved in the industrialization process. Surface-induced fluids were observed in all reviewed systems and played a critical role in physicochemical properties and structures of outside fluid. It can even be regarded as a new interface, when the adsorption layer has a strong interaction with the solid surface. Finally, we proposed a perspective on scientific challenges in the modern chemical engineering processes and outlined future prospects.展开更多
Treatment of male urethral trauma is always a challenging problem.In China,as the incidence of urethral trauma keeps rising,more and more studies relating to this are being published.To compare the outcome of differen...Treatment of male urethral trauma is always a challenging problem.In China,as the incidence of urethral trauma keeps rising,more and more studies relating to this are being published.To compare the outcome of different emergency treatments in China and other countries,we searched Chinese and English literature about this topic in the past 16 years.A total of 167 studies involving 5314 patients were included,with 144 in Chinese and 23 in English.All studies were retrospective in nature.Based on the analyses,surgical methods include open realignment,endoscopic realignment and primary repair,and we summarized and compared the success rate and complications(mainly erectile dysfunction and incontinence)of each method.We found that realignment of posterior urethra has similar success rate in China and other countries,but the outcome of realignment of anterior urethra is variable.The reason remains unknown.While long abandoned in Western countries,primary repair of anterior urethra is still an option in China and has high success rate.展开更多
The development and utilization of new environmental film is an important measure to tackle the residual film pollution, protect the ecological environment and promote the sustainable development of agriculture. The t...The development and utilization of new environmental film is an important measure to tackle the residual film pollution, protect the ecological environment and promote the sustainable development of agriculture. The types of new environmental film and their development status were reviewed from the aspects of photodegradable film, biodegradable film, photo-biodegradable film, liquid film, paper film and bast fiber film. In terms of the experimental research status of environmental films in China, analysis and comparisons were made from three aspects including the different types, the same type and imported environment-friendly film. Suggestions were proposed for the research and development prospect of environmental film.展开更多
Human pluripotent stem cells(hPSCs)are important resources for cell-based therapies and pharmaceutical applications.In order to realize the potential of hPSCs,it is critical to develop suitable technologies required f...Human pluripotent stem cells(hPSCs)are important resources for cell-based therapies and pharmaceutical applications.In order to realize the potential of hPSCs,it is critical to develop suitable technologies required for specific applications.Most hPSC technologies depend on cell culture,and are critically influenced by culture medium composition,extracellular matrices,handling methods,and culture platforms.This review summarizes the major technological advances in hPSC culture,and highlights the opportunities and challenges in future therapeutic applications.展开更多
Ca^(2+)/Na+separation is a common problem in industrial applications,biological and medical fields.However,Ca^(2+)and Na+have similar ionic radii and hydration radii,thus Ca^(2+)/Na+separation is challenging.Inspired ...Ca^(2+)/Na+separation is a common problem in industrial applications,biological and medical fields.However,Ca^(2+)and Na+have similar ionic radii and hydration radii,thus Ca^(2+)/Na+separation is challenging.Inspired by biological channels,group modification is one of the effective methods to improve the separation performance.In this work,molecular dynamics simulations were performed to investigate the effects of different functional groups(COO,NH3+)on the separation performance of Ca^(2+)and Na+through graphene nanopores under an electric field.The pristine graphene nanopore was used for comparison.Results showed that three types of nanopores preferred Ca^(2+)to Na+,and Ca^(2+)/Na+selectivity followed the order of GE-COO(4.06)>GE(1.85)>GE-NH3+(1.63).Detailed analysis of ionic hydration microstructure shows that different nanopores result in different hydration factors for the second hydration layer of Ca^(2+)and the first layer of Na+.Such different hydration factors corresponding to the dehydration ability can effectively evaluate the separation performance.In addition,the breaking of hydrogen bonds between water molecules due to electrostatic effects can directly affect the dehydration ability.Therefore,the electrostatic effect generated by group modification will affect the ionic hydration microstructure,thus reflecting the differences in dehydration ability.This in turn affects the permeable and separation performance of cations.The results of this work provide perceptive guidelines for the application of graphene-based membranes in ion separation.展开更多
The dehydration of water by dimethyl carbonate(DMC)is of great significance for its application in electrochemistry and oil industry.With the rapid development of nanomaterial,one-dimensional(e.g.carbon nanotube(CNT))...The dehydration of water by dimethyl carbonate(DMC)is of great significance for its application in electrochemistry and oil industry.With the rapid development of nanomaterial,one-dimensional(e.g.carbon nanotube(CNT))and two-dimensional(e.g.lamellar graphene)materials have been widely used for molecular sieving.In this work,the molecular behavior of dimethyl carbonate/water mixture confined in CNT with varying diameters was studied based on molecular dynamics simulation.Due to different van der Waals interactions for the components in the mixtures with the solid surface,DMC molecules are preferentially adsorbed on the inner surface of the pore wall and formed an adsorption layer.Comparing with the pure water molecules confined in CNT,the adsorption DMC layer shows notable effect on the local compositions and microstructures of water molecules under nanoconfinement,which may result in different water mobility.Our analysis shows that the surface-induced DMC molecules can destroy the hydrogen bonding network of water molecules and result in an uniform and dispersed distribution of water molecules in the tube.These clear molecular understandings can be useful in material design for membrane separation.展开更多
Tungsten telluride thin films were successfully prepared on monocrystal sapphire substrates by using atomic layer de-position and chemical vapor deposition technology,and the effects of different tellurization tempera...Tungsten telluride thin films were successfully prepared on monocrystal sapphire substrates by using atomic layer de-position and chemical vapor deposition technology,and the effects of different tellurization temperatures on the properties of tungsten telluride films were investigated.The growth rate,crystal structure and composition of the film samples were character-ized and analyzed by using scanning electron microscope,Raman spectroscopy and X-ray photoelectron spectroscopy.The res-ults showed that tungsten telluride thin films with good crystal orientation in(001)were obtained at telluride temperature of 550℃.When the telluride temperature reached 570℃,the tungsten telluride began to decompose and unsaturated mag-netoresistance was found.展开更多
The so-called organic Rankine cycle(ORC)is an effective technology allowing heat recovery from lower temperature sources.In the present study,to improve its thermal efficiency,a preheated ejector using exhaust steam c...The so-called organic Rankine cycle(ORC)is an effective technology allowing heat recovery from lower temperature sources.In the present study,to improve its thermal efficiency,a preheated ejector using exhaust steam coming from the expander is integrated in the cycle(EPORC).Considering net power output,pump power,and thermal efficiency,the proposed system is compared with the basic ORC.The influence of the ejector ratio(ER)of the preheated ejector on the system performances is also investigated.Results show that the net power output of the EPORC is higher than that of the basic ORC due to the decreasing pump power.Under given working conditions,the average thermal efficiency of EPORC is 29%higher than that of ORC.The ER has a great impact on the performance of EPORC by adjusting the working fluid fed to the pump,leading to significant variations of the pump work Moreover,the ER has a remarkable effect on the working fluid temperature lift(TL)at the evaporator inlet,thus reducing the evaporator heat load.According to the results,the thermal efficiency of EPORC increases by 30%,when the ER increases from 0.05 to 0.4.展开更多
Energy transition towards clean,efficient energy supply has been a common sense of the government and public in China.However,lacking reasonable planning will lead to undisciplined development,resource waste,and exces...Energy transition towards clean,efficient energy supply has been a common sense of the government and public in China.However,lacking reasonable planning will lead to undisciplined development,resource waste,and excessive investment.In this context,this paper investigates potential pathways of Beijing energy transition towards a high-level low-carbon,clean and efficient energy system in 2035 with an extended energysocpe model.Firstly,based on available data,future energy demands are predicted by a newly proposed hybrid forecasting method,which combines the traditional regression model,grey model,and support vector machine model with an entropy-based weighted factor.Secondly,the superstructure-based optimization model is employed to investigate the system configuration and operation strategy of the future Beijing energy system.Finally,the uncertainty impact of electricity price,natural gas price,hydrogen price,and the capital expenditures of electrolyzer and steam methane reforming for hydrogen applications are studied.The forecasting results show that all walks of life will witness a continuously increasing energy demand in multiple sectors of Beijing towards 2035.The planning results suggest that the imported electricity and natural gas will dominate the energy supply of Beijing in 2035 with a contribution of 86%of the energy resources consumption of 384 TWh.Moreover,the energy system presents a high end-use electrification level of 65%and high penetration of efficient technologies,which supply 119 TWh via combined heat and power,26 TWh via heat pump and 95 TWh via district heating network.The energy use of various sectors of energy resources,technologies and end-use are closely related.Hydrogen will have an increased penetration in the private mobility sector,but the locally generated hydrogen is mainly from steam methane reforming technology.展开更多
Fluorite-structured oxides constitute an important category of oxides with a wide range of high-temperature applications.Following the concept of high entropy,high-entropy fluorite oxides(HEFOs)have showcased intrigui...Fluorite-structured oxides constitute an important category of oxides with a wide range of high-temperature applications.Following the concept of high entropy,high-entropy fluorite oxides(HEFOs)have showcased intriguing high-temperature application potential.However,unlocking this potential necessitates an assessment of their long-term stability under high-temperature conditions.In this study,we conducted a prolonged heat treatment at 1000℃on typical HEFO,specifically(CeHfZrGdLa)O_(x).After 100 h,high-intensity X-ray diffraction(XRD)revealed a transition from a single-phase fluorite to a multi-phase configuration.Further investigation by analytical electron microscoy(AEM)demonstrated that this degradation resulted from facilitated element diffusion and consequent escalating chemical fluctuation at high temperatures,leading to spontaneous segregation and separation of Ce and La elements,forming Ce-rich,La-poor,and La-rich phases.Notably,the La-rich phase spontaneously transformed from a fluorite structure(space group Fm3m)to a bixbyite structure(space group Ia3)at elevated temperatures,resulting in the appearance of superstructure reflection in XRD profiles and electron diffraction patterns.Despite the intricate phase decomposition,the energy band gap showed minimal variation,suggesting potential property stability of(CeHfZrGdLa)O_(x)across a broad range of compositions.These findings offer valuable insights into the future applications of HEFOs.展开更多
Proteins secreted by Gram-negative bacteria are tightly linked to the virulence and adaptability of these microbes to environmental changes.Accurate identification of such secreted proteins can facilitate the investig...Proteins secreted by Gram-negative bacteria are tightly linked to the virulence and adaptability of these microbes to environmental changes.Accurate identification of such secreted proteins can facilitate the investigations of infections and diseases caused by these bacterial pathogens.However,current bioinformatic methods for predicting bacterial secreted substrate proteins have limited computational efficiency and application scope on a genome-wide scale.Here,we propose a novel deep-learning-based framework—DeepSecE—for the simultaneous inference of multiple distinct groups of secreted proteins produced by Gram-negative bacteria.DeepSecE remarkably improves their classification from nonsecreted proteins using a pretrained protein language model and transformer,achieving a macro-average accuracy of 0.883 on 5-fold cross-validation.Performance benchmarking suggests that DeepSecE achieves competitive performance with the state-of-the-art binary predictors specialized for individual types of secreted substrates.The attention mechanism corroborates salient patterns and motifs at the N or C termini of the protein sequences.Using this pipeline,we further investigate the genome-wide prediction of novel secreted proteins and their taxonomic distribution across~1,000 Gram-negative bacterial genomes.The present analysis demonstrates that DeepSecE has major potential for the discovery of disease-associated secreted proteins in a diverse range of Gram-negative bacteria.An online web server of DeepSecE is also publicly available to predict and explore various secreted substrate proteins via the input of bacterial genome sequences.展开更多
Comprehensive Summary,A transition-metal-free one-pot direct synthesis of tetrathiophosphates(R^(1)S)_(2)P(S)SR^(2) from white phosphorus(P_(4)),through intermediate sodium alkyltetrathiophosphates(R^(1)S)_(2)P(S)SNa,...Comprehensive Summary,A transition-metal-free one-pot direct synthesis of tetrathiophosphates(R^(1)S)_(2)P(S)SR^(2) from white phosphorus(P_(4)),through intermediate sodium alkyltetrathiophosphates(R^(1)S)_(2)P(S)SNa,is presented.In the presence of NaSH,various disulfides such as diaryl disulfidbges and dialkyl disulfides are easily coupled with P_(4) to give sodium alkyltetrathiophosphates(R^(1)S)_(2)P(S)SNa in almost quantitative yield,which react with alkyl halides in one pot to generate(R^(1)S)_(2)P(S)SR2.Furthermore,S-(2-cyanoethyl)-substituted tetrathiophosphates(R^(1)S)_(2)P(S)SCH_(2)CH_(2)CN are successfully designed as a kind of tetrathiophosphorylation reagent to react with diaryl iodonium salts involving deprotection-dealkylation process.展开更多
Polarization-independent liquid-crystal(LC)phase modulators can significantly improve the efficiency and reduce the complexity of optical systems.However,achieving good polarization independence for LC phase modulator...Polarization-independent liquid-crystal(LC)phase modulators can significantly improve the efficiency and reduce the complexity of optical systems.However,achieving good polarization independence for LC phase modulators with a simple structure is difficult.A light-controlled azimuth angle(LCAA)process based on the optical rotatory effect of cholesteric liquid crystals(CLC)was developed for fabricating single-layer,multi-microdomain,orthogonally twisted(MMOT)structures.The developed LC phase modulator with a single-layer MMOT structure may have a low polarization dependence with a large phase depth.This device shows good potential for applications in optical communications,wearable devices,and displays.展开更多
基金financial support from the National Natural Science Foundation of China(22008107,21838004)DTRA through the grant HDTRA11910008 of the USA。
文摘The research on the adsorption equilibria,kinetics,and increase in process temperature of the volatile organic compound(VOC)adsorption in porous materials ensures safe production,thereby reducing production costs and improving separation efficiency.Therefore,it is critical in predicting the entire adsorption process based on minimal or no experimental input of the adsorbate and adsorbent.We discuss,in this review,the factors that affect the adsorption performance of VOCs in activated carbons,including the adsorption equilibrium,adsorption kinetics,and exotherm during adsorption.Subsequently,the existing prediction models are summarized and compared concerning the adsorption equilibrium,adsorption kinetics,and exothermic process of adsorption.We then propose a new prediction model based on intermolecular interaction and provide an outlook toward the design and manipulation of efficient adsorbents for the VOC system.
基金Supported by the National Natural Science Foundation of China(21176112,21576130,21490584,51005123)Qing Lan Project,the State Key Laboratory of Materials-Oriented Chemical Engineering(KL15-03)+1 种基金Specialized Research Fund for the Doctoral Program of Higher Education(20133221110001)the Natural Science Foundation of Jiangsu Province(BK20130062)
文摘How to reduce flow resistance of nano-confined fluids to achieve a high flux is a new challenge for modern chemical engineering applications, such as membrane separation and nanofluidic devices. Traditional models are inapplicable to explain the significant differences in the flow resistance of different liquid–solid systems.On the other hand, friction reduction in liquid nano-lubrication has received considerable attention during the past decades. Both fields are exposed to a common scientific issue regarding friction reduction during liquid–solid relative motion at nanoscale. A promising approach to control the flow resistance of nano-confined fluids is to reference the factors affecting liquid nano-lubrication. In this review, two concepts of the friction coefficient derived from fluid flow and tribology were discussed to reveal their intrinsic relations. Recent progress on low or ultra-low friction coefficients in liquid nano-lubrication was summarized based on two situations. Finally, a new strategy was introduced to study the friction coefficient based on analyzing the intermolecular interactions through an atomic force microscope(AFM), which is a cutting-point to build a new model to study flowresistance at nanoscale.
基金Supported by the National NaturalScience Foundation of China(21576130,21490584)Project of Jiangsu Natural Science Foundation of China(BK20171464)+1 种基金Qing Lan ProjectJiangsu Overseas Visiting Scholar Program for University Prominent Young&Middleaged Teachers and Presidents
文摘Monolayer molybdenum disulfide(MoS2) is a novel two-dimensional material that exhibits potential application in lubrication technology. In this work, molecular dynamics was used to investigate the lubrication behaviour of different polar fluid molecules(i.e., water, methanol and decane) confined in monolayer Mo S2 nanoslits. The pore width effect(i.e., 1.2, 1.6 and 2.0 nm) was also evaluated. Results revealed that decane molecules exhibited good lubricating performance compared to the other two kinds of molecules. The friction coefficient followed the order of decane b methanol b water, and decreased evidently as the slit width increased, except for decane. Analysis of the spatial distribution and mobility of different confined fluid molecules showed that a solid-like layer was formed near the slit wall. This phenomenon led to the extra low friction coefficient of confined decane molecules.
基金Supported by the National Natural Science Foundation of China(21878144,21576130,21490584 and 21838004)Project of Jiangsu Natural Science Foundation of China(BK20171464)+2 种基金Qing Lan ProjectJiangsu Overseas Visiting Scholar Program for University Prominent Young&Middle-aged Teachers and Presidentsthe Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘In modern chemical engineering processes, solid interface involvement is the most important component of process intensification techniques, such as nanoporous membrane separation and heterogeneous catalysis. The fundamental mechanism underlying interfacial transport remains incompletely understood given the complexity of heterogeneous interfacial molecular interactions and the high nonideality of the fluid involved. Thus, understanding the effects of interface-induced fluid microstructures on flow resistance is the first step in further understanding interfacial transport. Molecular simulation has become an indispensable method for the investigation of fluid microstructure and flow resistance. Here, we reviewed the recent research progress of our group and the latest relevant works to elucidate the contribution of interface-induced fluid microstructures to flow resistance.We specifically focused on water, ionic aqueous solutions, and alcohol–water mixtures given the ubiquity of these fluid systems in modern chemical engineering processes. We discussed the effects of the interfaceinduced hydrogen bond networks of water molecules, the ionic hydration of ionic aqueous solutions, and the spatial distributions of alcohol and alcohol–water mixtures on flow resistance on the basis of the distinctive characteristics of different fluid systems.
基金supported by the National Natural Science Foundation of China [21878144, 21729601, 21838004]the Foundation for Innovative Research Groups of the National Natural Science Foundation of China [21921006]+3 种基金Project of Jiangsu Natural Science Foundation of China [BK20171464]Project of Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the Kempe Foundation in Swedengrant of Ministry of Research and Innovation, CNCS-UEFISCDI, Romania, project number PN-III-P4-ID-PCCF-2016-0050, within PNCDI III and the Swedish Science Council (VR)。
文摘In modern chemical engineering processes, the involvement of solid/fluid interface is the most important component of process intensification techniques, such as confined membrane separation and catalysis. In the review, we summarized the research progress of the latest theoretical and experimental works to elucidate the contribution of interface to the fluid properties and structures at nano-and micro-scale. We mainly focused on water, alcohol aqueous solution, and ionic liquids, because they are classical systems in interfacial science and/or widely involved in the industrialization process. Surface-induced fluids were observed in all reviewed systems and played a critical role in physicochemical properties and structures of outside fluid. It can even be regarded as a new interface, when the adsorption layer has a strong interaction with the solid surface. Finally, we proposed a perspective on scientific challenges in the modern chemical engineering processes and outlined future prospects.
文摘Treatment of male urethral trauma is always a challenging problem.In China,as the incidence of urethral trauma keeps rising,more and more studies relating to this are being published.To compare the outcome of different emergency treatments in China and other countries,we searched Chinese and English literature about this topic in the past 16 years.A total of 167 studies involving 5314 patients were included,with 144 in Chinese and 23 in English.All studies were retrospective in nature.Based on the analyses,surgical methods include open realignment,endoscopic realignment and primary repair,and we summarized and compared the success rate and complications(mainly erectile dysfunction and incontinence)of each method.We found that realignment of posterior urethra has similar success rate in China and other countries,but the outcome of realignment of anterior urethra is variable.The reason remains unknown.While long abandoned in Western countries,primary repair of anterior urethra is still an option in China and has high success rate.
基金Supported by the Key Programs for Science and Technology Development of Shanxi Province(20140311007-4)
文摘The development and utilization of new environmental film is an important measure to tackle the residual film pollution, protect the ecological environment and promote the sustainable development of agriculture. The types of new environmental film and their development status were reviewed from the aspects of photodegradable film, biodegradable film, photo-biodegradable film, liquid film, paper film and bast fiber film. In terms of the experimental research status of environmental films in China, analysis and comparisons were made from three aspects including the different types, the same type and imported environment-friendly film. Suggestions were proposed for the research and development prospect of environmental film.
基金Supported by University of Macao Multi-Year Research Grants,No.MYRG2015-00228-FHS and MYRG2018-00135-FHSMacao Science and Technology Development Fund,No.FDCT/131/2014/A3 and FDCT/056/2015/A2
文摘Human pluripotent stem cells(hPSCs)are important resources for cell-based therapies and pharmaceutical applications.In order to realize the potential of hPSCs,it is critical to develop suitable technologies required for specific applications.Most hPSC technologies depend on cell culture,and are critically influenced by culture medium composition,extracellular matrices,handling methods,and culture platforms.This review summarizes the major technological advances in hPSC culture,and highlights the opportunities and challenges in future therapeutic applications.
基金supported by the National Science Foundation of China(21878144,21838004 and 21776123)the Foundation for Innovative Research Groups of the National Natural Science Foun-dation of China(21921006).
文摘Ca^(2+)/Na+separation is a common problem in industrial applications,biological and medical fields.However,Ca^(2+)and Na+have similar ionic radii and hydration radii,thus Ca^(2+)/Na+separation is challenging.Inspired by biological channels,group modification is one of the effective methods to improve the separation performance.In this work,molecular dynamics simulations were performed to investigate the effects of different functional groups(COO,NH3+)on the separation performance of Ca^(2+)and Na+through graphene nanopores under an electric field.The pristine graphene nanopore was used for comparison.Results showed that three types of nanopores preferred Ca^(2+)to Na+,and Ca^(2+)/Na+selectivity followed the order of GE-COO(4.06)>GE(1.85)>GE-NH3+(1.63).Detailed analysis of ionic hydration microstructure shows that different nanopores result in different hydration factors for the second hydration layer of Ca^(2+)and the first layer of Na+.Such different hydration factors corresponding to the dehydration ability can effectively evaluate the separation performance.In addition,the breaking of hydrogen bonds between water molecules due to electrostatic effects can directly affect the dehydration ability.Therefore,the electrostatic effect generated by group modification will affect the ionic hydration microstructure,thus reflecting the differences in dehydration ability.This in turn affects the permeable and separation performance of cations.The results of this work provide perceptive guidelines for the application of graphene-based membranes in ion separation.
基金supported by the National Science Foundation of China(21878144,21729601 and 21838004)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(21921006)+3 种基金Project of Jiangsu Natural Science Foundation of China(BK20171464)Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Kempe Foundation in Swedena grant of Ministry of Research and Innovation,CNCS-UEFISCDI,project number PN-III-P4-ID-PCCF-2016-0050,within PNCDI III and the Swedish Science Council(VR)。
文摘The dehydration of water by dimethyl carbonate(DMC)is of great significance for its application in electrochemistry and oil industry.With the rapid development of nanomaterial,one-dimensional(e.g.carbon nanotube(CNT))and two-dimensional(e.g.lamellar graphene)materials have been widely used for molecular sieving.In this work,the molecular behavior of dimethyl carbonate/water mixture confined in CNT with varying diameters was studied based on molecular dynamics simulation.Due to different van der Waals interactions for the components in the mixtures with the solid surface,DMC molecules are preferentially adsorbed on the inner surface of the pore wall and formed an adsorption layer.Comparing with the pure water molecules confined in CNT,the adsorption DMC layer shows notable effect on the local compositions and microstructures of water molecules under nanoconfinement,which may result in different water mobility.Our analysis shows that the surface-induced DMC molecules can destroy the hydrogen bonding network of water molecules and result in an uniform and dispersed distribution of water molecules in the tube.These clear molecular understandings can be useful in material design for membrane separation.
基金supported by the National Key Research and Development Program of China(No.2018YFA0704804)Chinese Academy of Sciences Research Instruments and Equipment Development Project(No.ZDKYYQ20220001)。
文摘Tungsten telluride thin films were successfully prepared on monocrystal sapphire substrates by using atomic layer de-position and chemical vapor deposition technology,and the effects of different tellurization temperatures on the properties of tungsten telluride films were investigated.The growth rate,crystal structure and composition of the film samples were character-ized and analyzed by using scanning electron microscope,Raman spectroscopy and X-ray photoelectron spectroscopy.The res-ults showed that tungsten telluride thin films with good crystal orientation in(001)were obtained at telluride temperature of 550℃.When the telluride temperature reached 570℃,the tungsten telluride began to decompose and unsaturated mag-netoresistance was found.
基金This work was supported by the National Risk Assessment Laboratory of Agroproducts Processing Quality and Safety,Ministry of Agriculture and Rural Affairs(S2020KFKT-06).
文摘The so-called organic Rankine cycle(ORC)is an effective technology allowing heat recovery from lower temperature sources.In the present study,to improve its thermal efficiency,a preheated ejector using exhaust steam coming from the expander is integrated in the cycle(EPORC).Considering net power output,pump power,and thermal efficiency,the proposed system is compared with the basic ORC.The influence of the ejector ratio(ER)of the preheated ejector on the system performances is also investigated.Results show that the net power output of the EPORC is higher than that of the basic ORC due to the decreasing pump power.Under given working conditions,the average thermal efficiency of EPORC is 29%higher than that of ORC.The ER has a great impact on the performance of EPORC by adjusting the working fluid fed to the pump,leading to significant variations of the pump work Moreover,the ER has a remarkable effect on the working fluid temperature lift(TL)at the evaporator inlet,thus reducing the evaporator heat load.According to the results,the thermal efficiency of EPORC increases by 30%,when the ER increases from 0.05 to 0.4.
基金the National Natural Science Foundation of China(No.51821004)the Major Program of the National Natural Science Foundation of China(No.52090062)the Interdisciplinary Innovation Program of North China Electric Power University,and the China Scholarship Council(CSC).
文摘Energy transition towards clean,efficient energy supply has been a common sense of the government and public in China.However,lacking reasonable planning will lead to undisciplined development,resource waste,and excessive investment.In this context,this paper investigates potential pathways of Beijing energy transition towards a high-level low-carbon,clean and efficient energy system in 2035 with an extended energysocpe model.Firstly,based on available data,future energy demands are predicted by a newly proposed hybrid forecasting method,which combines the traditional regression model,grey model,and support vector machine model with an entropy-based weighted factor.Secondly,the superstructure-based optimization model is employed to investigate the system configuration and operation strategy of the future Beijing energy system.Finally,the uncertainty impact of electricity price,natural gas price,hydrogen price,and the capital expenditures of electrolyzer and steam methane reforming for hydrogen applications are studied.The forecasting results show that all walks of life will witness a continuously increasing energy demand in multiple sectors of Beijing towards 2035.The planning results suggest that the imported electricity and natural gas will dominate the energy supply of Beijing in 2035 with a contribution of 86%of the energy resources consumption of 384 TWh.Moreover,the energy system presents a high end-use electrification level of 65%and high penetration of efficient technologies,which supply 119 TWh via combined heat and power,26 TWh via heat pump and 95 TWh via district heating network.The energy use of various sectors of energy resources,technologies and end-use are closely related.Hydrogen will have an increased penetration in the private mobility sector,but the locally generated hydrogen is mainly from steam methane reforming technology.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.52150610487 and 51850410501).The authors acknowledge the help of Dr.Linlin Ma for UV-Vis spectra from the Instrumental Analytical Center of Shanghai Jiao Tong University.
文摘Fluorite-structured oxides constitute an important category of oxides with a wide range of high-temperature applications.Following the concept of high entropy,high-entropy fluorite oxides(HEFOs)have showcased intriguing high-temperature application potential.However,unlocking this potential necessitates an assessment of their long-term stability under high-temperature conditions.In this study,we conducted a prolonged heat treatment at 1000℃on typical HEFO,specifically(CeHfZrGdLa)O_(x).After 100 h,high-intensity X-ray diffraction(XRD)revealed a transition from a single-phase fluorite to a multi-phase configuration.Further investigation by analytical electron microscoy(AEM)demonstrated that this degradation resulted from facilitated element diffusion and consequent escalating chemical fluctuation at high temperatures,leading to spontaneous segregation and separation of Ce and La elements,forming Ce-rich,La-poor,and La-rich phases.Notably,the La-rich phase spontaneously transformed from a fluorite structure(space group Fm3m)to a bixbyite structure(space group Ia3)at elevated temperatures,resulting in the appearance of superstructure reflection in XRD profiles and electron diffraction patterns.Despite the intricate phase decomposition,the energy band gap showed minimal variation,suggesting potential property stability of(CeHfZrGdLa)O_(x)across a broad range of compositions.These findings offer valuable insights into the future applications of HEFOs.
基金the National Natural Science Foundation of China(32070572)the Foundation of Key Laboratory of Veterinary Biotechnology(shklab202005)+1 种基金Shanghai,China,and the Science and Technology Commission of Shanghai Municipality(19JC1413000)R.B.G.and J.S.were supported by grants from the Australian Research Council(ARC)(LP220200614).
文摘Proteins secreted by Gram-negative bacteria are tightly linked to the virulence and adaptability of these microbes to environmental changes.Accurate identification of such secreted proteins can facilitate the investigations of infections and diseases caused by these bacterial pathogens.However,current bioinformatic methods for predicting bacterial secreted substrate proteins have limited computational efficiency and application scope on a genome-wide scale.Here,we propose a novel deep-learning-based framework—DeepSecE—for the simultaneous inference of multiple distinct groups of secreted proteins produced by Gram-negative bacteria.DeepSecE remarkably improves their classification from nonsecreted proteins using a pretrained protein language model and transformer,achieving a macro-average accuracy of 0.883 on 5-fold cross-validation.Performance benchmarking suggests that DeepSecE achieves competitive performance with the state-of-the-art binary predictors specialized for individual types of secreted substrates.The attention mechanism corroborates salient patterns and motifs at the N or C termini of the protein sequences.Using this pipeline,we further investigate the genome-wide prediction of novel secreted proteins and their taxonomic distribution across~1,000 Gram-negative bacterial genomes.The present analysis demonstrates that DeepSecE has major potential for the discovery of disease-associated secreted proteins in a diverse range of Gram-negative bacteria.An online web server of DeepSecE is also publicly available to predict and explore various secreted substrate proteins via the input of bacterial genome sequences.
基金supported by the National Key Research and Development Program of China(2020YFA0608300)the NSFC(21772163,21778042 and 41876072)NFFTBS(J1310024)。
文摘Comprehensive Summary,A transition-metal-free one-pot direct synthesis of tetrathiophosphates(R^(1)S)_(2)P(S)SR^(2) from white phosphorus(P_(4)),through intermediate sodium alkyltetrathiophosphates(R^(1)S)_(2)P(S)SNa,is presented.In the presence of NaSH,various disulfides such as diaryl disulfidbges and dialkyl disulfides are easily coupled with P_(4) to give sodium alkyltetrathiophosphates(R^(1)S)_(2)P(S)SNa in almost quantitative yield,which react with alkyl halides in one pot to generate(R^(1)S)_(2)P(S)SR2.Furthermore,S-(2-cyanoethyl)-substituted tetrathiophosphates(R^(1)S)_(2)P(S)SCH_(2)CH_(2)CN are successfully designed as a kind of tetrathiophosphorylation reagent to react with diaryl iodonium salts involving deprotection-dealkylation process.
基金supported by the National Natural Science Foundation of China under Grant No.62175148。
文摘Polarization-independent liquid-crystal(LC)phase modulators can significantly improve the efficiency and reduce the complexity of optical systems.However,achieving good polarization independence for LC phase modulators with a simple structure is difficult.A light-controlled azimuth angle(LCAA)process based on the optical rotatory effect of cholesteric liquid crystals(CLC)was developed for fabricating single-layer,multi-microdomain,orthogonally twisted(MMOT)structures.The developed LC phase modulator with a single-layer MMOT structure may have a low polarization dependence with a large phase depth.This device shows good potential for applications in optical communications,wearable devices,and displays.