In recent years,the direct introduction of sulfonyl and sulfenyl groups into unsaturated substrates by using thiosulfonates as unique dual functional reagents has inarguably provided chemists a new platform for the di...In recent years,the direct introduction of sulfonyl and sulfenyl groups into unsaturated substrates by using thiosulfonates as unique dual functional reagents has inarguably provided chemists a new platform for the diverse synthesis of important S-containing derivatives.These 1,n-thiosulfonylation reactions usually feature simple procedures,100%atom economy,and high regioselectivity.This review focuses on the recent advancements in the transformations of thiosulfonates through 1,n-thiosulfonylation involving the formation of two distinct C-S bonds under transition-metal-catalyzed or metal-free conditions,where thiosulfonates act as both a sulfonyl and a sulfenyl component.展开更多
Bioactive glass-chitosan-alginate hybrid scaffolds （BG-C-A scaffolds） were fabricated using BG sol as a dual function additive, which behaves as both bioactive inorganic phase to confer the bioactivity and cross-lin...Bioactive glass-chitosan-alginate hybrid scaffolds （BG-C-A scaffolds） were fabricated using BG sol as a dual function additive, which behaves as both bioactive inorganic phase to confer the bioactivity and cross-linker to improve the structural stability and mechanical properties. The microstructure, physicochemical and mechanical properties, in vitro bioactivity and cellular biocompatibility of the scaffolds were investigated. The results indicated that BG component was successfully incorporated into the BG-C-A scaffolds through a facile BG sol-immersing method and the original interconnected microstructure could be well preserved. The obtained BG-C-A scaffolds showed improved mechanical properties and structural stability as compared to C-A scaffolds. At the same time, they presented excellent in vitro bioactivity and cellular compatibility. All these results demonstrated that these BG-C-A scaffolds have promising potential for tissue engineering.展开更多
A family of Said-Bézier type generalized Ball （SBGB） bases and surfaces with a parameter H over triangular domain is introduced,which unifies Bézier surface and Said-Ball surface and includes several inter...A family of Said-Bézier type generalized Ball （SBGB） bases and surfaces with a parameter H over triangular domain is introduced,which unifies Bézier surface and Said-Ball surface and includes several intermediate surfaces. To convert different bases and surfaces,the dual functionals of bases are presented. As an application of dual functionals,the subdivision formulas for surfaces are established.展开更多
Integrated CO_(2)capture and utilization(ICCU)technology requires dual functional materials(DFMs)to carry out the process in a single reaction system.The influence of the calcination atmosphere on efficiency of 4%Ru-8...Integrated CO_(2)capture and utilization(ICCU)technology requires dual functional materials(DFMs)to carry out the process in a single reaction system.The influence of the calcination atmosphere on efficiency of 4%Ru-8%Na_(2)CO_(3)-8%CaO/γ-Al_(2)O_(3)DFM is studied.The adsorbent precursors are first co-impregnated onto alumina and calcined in air.Then,Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols:static air in muffle or under different mixtures(10%H_(2)/N_(2),50%H_(2)/N_(2)and N_(2))streams.Samples are characterized by XRD,N_(2)adsorption-desorption,H_(2)chemisorption,TEM,XPS,H_(2)-TPD,H_(2)-TPR,CO_(2)-TPD and TPSR.The catalytic behavior is evaluated,in cycles of CO_(2)adsorption and hydrogenation to CH_(4),and temporal evolution of reactants and products concentrations is analyzed.The calcination atmosphere influences the physicochemical properties and,ultimately,activity of DFMs.Characterization data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic activity.DFM calcined under N_(2)flow(RuNaCa-N_(2))shows the highest CH_(4)production(449μmol/g at 370℃),because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases,maximizing the specific surface area,the Ru-basic sites interface and the participation of different basic sites in the CO_(2)methanation reaction.Thus,the calcination in a N_(2)flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO_(2)adsorption and hydrogenation applications.展开更多
The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual...The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual functionals for the generalized Ball basis of Wang-Said type. The relevant basis transformation formulae are also worked out.展开更多
Flexible electronic devices are integral for meeting the diverse and complex requirements of wearable and multifunctional applications.Conductive papers with characteristics of light-weight,good processability,and deg...Flexible electronic devices are integral for meeting the diverse and complex requirements of wearable and multifunctional applications.Conductive papers with characteristics of light-weight,good processability,and degradability,offer significant benefits to wearable electronics.However,it often suffers from discontinuous distribution of the conductive network,inferior ductility,and conformability,which hinders its application.Herein,we present a conductive paper consisting of high-performance aramid paper as the matrix,and MXene and carbon nanotubes as the conductive fillers,fabricated through a mature papermaking technique and a kirigami design.The resultant dual functional kirigami paper(DFKP)exhibits desirable flexibility and breathability,excellent conductivity(1245.7 S/m),superior mechanical properties(tensile strength of 53.8 MPa),and ideal ductility(an elongation of~612.1%),demonstrating promising capabilities in simultaneously wearable motion-sensing and electrical thermotherapy applications.The DFKP enables flexible deformation,better skin attachment,and three-dimensional(3D)supports for precise monitoring of physiological changes in response to different motions,featuring rapid response and recovery times as short as 30 ms.Furthermore,it exhibits a rapid temperature increase and reaches 95.3℃within 35 s upon applying a voltage of 6 V.Remarkably,the DFKP proves stabilities under repeated deformations,maintaining a stable operational state even after 8000 cycles of stretching.Therefore,this unique wearable DFKP holds great promise for simultaneously being employed in human health monitoring and electrothermal therapy.展开更多
Direct air capture(DAC)is an emerging technology aimed at mitigating global warming.However,conventional DAC technologies and the subsequent utilization processes are complex and energy-intensive.An integrated system ...Direct air capture(DAC)is an emerging technology aimed at mitigating global warming.However,conventional DAC technologies and the subsequent utilization processes are complex and energy-intensive.An integrated system of direct air capture and utilization(IDACU)via in-situ catalytic conversion to fuels and chemicals is a promising approach,although it remains in the early stages of development.This review examines the current technical routes of IDACU,including solid-based dual-functional materials(DFMs)through thermo-catalysis,IDACU using liquid sorbents with thermo-catalysis,and non-thermal conversion methods.It covers the basic principles,reaction conditions,main products,material types,and the existing problems and challenges associated with these technical routes.Additionally,it discusses the recent advancements in solid-based DFMs for IDACU,with particular attention to the differences in material characteristics between carbon capture from flue gases(ICCU)and DAC.While IDACU technology holds significant promise,it still faces numerous challenges,especially in the design of advanced materials.展开更多
A fluorescent active organic–inorganic hybrid material Py N-SBA-15 was synthesized by implementing pyrene derivatives into mesoporous SBA-15 silica.Py N-SBA-15 had detection and removal functionalities toward Al^(3+)...A fluorescent active organic–inorganic hybrid material Py N-SBA-15 was synthesized by implementing pyrene derivatives into mesoporous SBA-15 silica.Py N-SBA-15 had detection and removal functionalities toward Al^(3+),Cu^(2+),and Hg^(2+).On the one hand,Py N-SBA-15 was used as a fluorescence sensor and displayed high sensitivity toward Al^(3+),Cu^(2+),and Hg^(2+)cations (limit of detection:8.0×10^(-7),1.1×10^(-7),and 2.9×10^(-6)mol·L^(–1),respectively) among various analytes with“turn-off”response.On the other hand,the adsorption studies for these toxic analytes (Cu^(2+),Hg^(2+),and Al^(3+)) showed that the ion removal capacity could reach up to 45,581,and 85 mg·g^(-1),respectively.Moreover,the Langmuir isotherm models were better fitted with the adsorption data,indicating that the adsorption was mono-layer adsorption.Kinetic analysis revealed that the adsorption process was well described by the pseudo-second-order kinetic model for Cu^(2+)and Hg^(2+)and pseudo-first-order kinetic model for Al^(3+).The prepared silica material could be reused in four recycles without significantly decreasing its adsorption capacity.Therefore,the Py N-SBA-15 material can serve as a promising candidate for the simultaneous rapid detection and efficient adsorption of metal ions.展开更多
An unprecedented gold-catalyzed ketene C=O/C=C bifunctionalization method has been developed.Mechanistic studies and density function theory(DFT)calculations indicate that the reaction is initiated by gold-catalyzed W...An unprecedented gold-catalyzed ketene C=O/C=C bifunctionalization method has been developed.Mechanistic studies and density function theory(DFT)calculations indicate that the reaction is initiated by gold-catalyzed Wolff rearrangement of diazoketone to form the ketene intermediate,followed by intermolecular nucleophilic addition and terminated with two divergent cyclization processes via enol intermediates.In the case with alcohols as the nucleophiles,the reaction goes through a C-5-endodig carbocyclization to give the indene products;whereas,O-7-endo-dig cyclization occurs dominantly when indoles/pyrroles are used as the nucleophiles,delivering the 7-membered benzo[d]oxepines.In comparison with the well-documented cycloaddition and nucleophilic addition reactions,this cascade reaction features a novel reaction pattern for the ketene dual functionalization through addition with nucleophile and electrophile in sequence.展开更多
The penalty function method, presented many years ago, is an important nu- merical method for the mathematical programming problems. In this article, we propose a dual-relax penalty function approach, which is signifi...The penalty function method, presented many years ago, is an important nu- merical method for the mathematical programming problems. In this article, we propose a dual-relax penalty function approach, which is significantly different from penalty func- tion approach existing for solving the bilevel programming, to solve the nonlinear bilevel programming with linear lower level problem. Our algorithm will redound to the error analysis for computing an approximate solution to the bilevel programming. The error estimate is obtained among the optimal objective function value of the dual-relax penalty problem and of the original bilevel programming problem. An example is illustrated to show the feasibility of the proposed approach.展开更多
Starting from the hydroxylamine (dimethyl amino ethanol, triethanolamine) and 1,3-propane sultone, a series of hydroxyl and sulfonyl dual-functionalized zwitterionic salts and corresponding acidic room temperature ion...Starting from the hydroxylamine (dimethyl amino ethanol, triethanolamine) and 1,3-propane sultone, a series of hydroxyl and sulfonyl dual-functionalized zwitterionic salts and corresponding acidic room temperature ionic liquids have been synthesized. The hydroxyl groups of the synthesized substances were confirmed by the 1H NMR measurement. These zwitterionic salts and ionic liquids may be used for synthesizing other functionalized ionic liquids or ionic liquid-polymer (polyelectrolyte).展开更多
In this paper,we proved that the infinitesimal generator of a strongly continuous cosine operator function is preserved under the time-dependent perturbation in the sun-reflexive case,where the perturbed operator is ...In this paper,we proved that the infinitesimal generator of a strongly continuous cosine operator function is preserved under the time-dependent perturbation in the sun-reflexive case,where the perturbed operator is a bounded linear operator from X into a bigger space Xθ(not X),then the corresponding 2-order abstract Cauchy problem is uniformly well-posed.展开更多
The functionally graded thermal barrier coatings （FG-TBCs） with 80%ZrO2-13%CeO2-7%Y2O3 （C-YSZ）/NiCoCrAlY were prepared using a recently developed supersonic plasma spraying（S-PS） with dual powder feed ports syst...The functionally graded thermal barrier coatings （FG-TBCs） with 80%ZrO2-13%CeO2-7%Y2O3 （C-YSZ）/NiCoCrAlY were prepared using a recently developed supersonic plasma spraying（S-PS） with dual powder feed ports system. The thermal shock experiment of FG-TBCs specimens was carried out by means of the automatic thermal cycle device, in which the samples were heated to 1200℃ by oxygen-acetylene flame jet then water-quenched to ambient temperature. The temperature—time curves of specimens and photographs can be watched on-line and recorded by a computer during the test. The results show that the totally 1mm-thick FG-TBCs have excellent thermal shock resistance due to the fact that the coatings have no any peeling-off after 200 thermal cycles. The microstructures and morphologies of FG-TBCs were characterized and analyzed by SEM.展开更多
Bisphenol A （BPA） was one of the environmental hormones that would cause endocrine and metabolic disorders in human or wildlife. This paper proposed a method to detect the trace amounts of BPA in water samples by fu...Bisphenol A （BPA） was one of the environmental hormones that would cause endocrine and metabolic disorders in human or wildlife. This paper proposed a method to detect the trace amounts of BPA in water samples by fully utilizing the enrichment and resonance amplification functions of a new dual-functional membrane. In this work, gold nanoparticles （AuNPs） modified by 3-amino-5-mercapto-1,2,4-triazole （AMT） were embedded in nylon66 membrane to produce a dual-functional membrane which could carry out sample enrichment by capturing BPA molecules from water and achieve resonance amplification by connecting BPA to the surfaces of AuNPs. By designing an automatic sampler for large-volume enrichment, the SERS enhancement factor （EF） of the method was further improved to 1.2 × 105. The present method had been successfully applied to detect BPA in drinking water and environmental water by SERS with the detection limit of 0.012 μg/L. It had the potential for on-site detecting of BPA in various water samples.展开更多
This article reports on the synthesis of acrylate monomer from renewable material. Vanillin was selected to be the start material to produce new monomer called vanillin acrylate and abbreviated by (VA). It has been su...This article reports on the synthesis of acrylate monomer from renewable material. Vanillin was selected to be the start material to produce new monomer called vanillin acrylate and abbreviated by (VA). It has been successfully investigated by 1H, 13C NMR, IR and UV and all results were in logic state. The next step was to synthetize three different thermo-responsive functional copolymers by incorporation of three different molar ratios of vanillin acrylate (10, 20, 30 mol%) with N-Isopropylacrylamide via free radical polymerization by AIBN as initiator in solution. All copolymers were deduced by 1NMR and IR and all showed the presence of aldehyde group. The copolymer was used for grafting of tryptophan and β-alanine through the chemical link between amino group and the active aldehyde group by click reactions to form Schiff’s base imine compounds. Moreover, polymers were also elucidated by 1HNMR, IR and UV, Size Exclusion Chromatography (SEC) was used for the molecular weight determination, differential scanning calorimeter (DSC) for glass temperature of solid polymers, XRD for crystallinity. UV-vis Spectroscopy was used for the determination of phase separation or the lower critical solution temperature (Tc) of polymers solution not only in deionized water but in pH5 and pH11. The mount of conversation and linked amino acid was determined by UV-vis Spectroscopy.展开更多
The present work is devoted to define a generalized Green’s function solution for the dual-phase-lag model in homogeneous materials in a unified manner .The high-order mixed derivative with respect to space and time ...The present work is devoted to define a generalized Green’s function solution for the dual-phase-lag model in homogeneous materials in a unified manner .The high-order mixed derivative with respect to space and time which reflect the lagging behavior is treated in special manner in the dual-phase-lag heat equation in order to construct a general solution applicable to wide range of dual-phase-lag heat transfer problems of general initial-boundary conditions using Green’s function solution method. Also, the Green’s function for a finite medium subjected to arbitrary heat source and arbitrary initial and boundary conditions is constructed. Finally, four examples of different physical situations are analyzed in order to illustrate the accuracy and potentialities of the proposed unified method. The obtained results show good agreement with works of [1-4].展开更多
We performed functional MRI examinations in six right-handed healthy subjects.During functional MRI scanning,transcranial direct current stimulation was delivered with the anode over the right primary sensorimotor cor...We performed functional MRI examinations in six right-handed healthy subjects.During functional MRI scanning,transcranial direct current stimulation was delivered with the anode over the right primary sensorimotor cortex and the cathode over the left primary sensorimotor cortex using dual-hemispheric transcranial direct current stimulation.This was compared to a cathode over the left supraorbital area using conventional single-hemispheric transcranial direct current stimulation. Voxel counts and blood oxygenation level-dependent signal intensities in the right primary sensorimotor cortex regions were estimated and compared between the two transcranial direct current stimulation conditions.Our results showed that dual-hemispheric transcranial direct current stimulation induced greater cortical activities than single-hemispheric transcranial direct current stimulation.These findings suggest that dual-hemispheric transcranial direct current stimulation may provide more effective cortical stimulation than single-hemispheric transcranial direct current stimulation.展开更多
基金financial support from the Natural Science Foundation of China(No.22001121)Natural Science Foundation of Jiangsu Province(No.BK20180690)+1 种基金Nanjing Tech University(Start-up Grant Nos.39837118 and39837146)Xuzhou Medical University(Start-up Grant No.RC20552038)。
文摘In recent years,the direct introduction of sulfonyl and sulfenyl groups into unsaturated substrates by using thiosulfonates as unique dual functional reagents has inarguably provided chemists a new platform for the diverse synthesis of important S-containing derivatives.These 1,n-thiosulfonylation reactions usually feature simple procedures,100%atom economy,and high regioselectivity.This review focuses on the recent advancements in the transformations of thiosulfonates through 1,n-thiosulfonylation involving the formation of two distinct C-S bonds under transition-metal-catalyzed or metal-free conditions,where thiosulfonates act as both a sulfonyl and a sulfenyl component.
基金supported by the National Natural Science Foundation of China(No. 51773209)the National Basic Research Program(No. 2017YFC1103300)the Strategic Priority Research Program of Chinese Academy of Sciences(No. XDB12020300)
文摘Bioactive glass-chitosan-alginate hybrid scaffolds （BG-C-A scaffolds） were fabricated using BG sol as a dual function additive, which behaves as both bioactive inorganic phase to confer the bioactivity and cross-linker to improve the structural stability and mechanical properties. The microstructure, physicochemical and mechanical properties, in vitro bioactivity and cellular biocompatibility of the scaffolds were investigated. The results indicated that BG component was successfully incorporated into the BG-C-A scaffolds through a facile BG sol-immersing method and the original interconnected microstructure could be well preserved. The obtained BG-C-A scaffolds showed improved mechanical properties and structural stability as compared to C-A scaffolds. At the same time, they presented excellent in vitro bioactivity and cellular compatibility. All these results demonstrated that these BG-C-A scaffolds have promising potential for tissue engineering.
文摘A family of Said-Bézier type generalized Ball （SBGB） bases and surfaces with a parameter H over triangular domain is introduced,which unifies Bézier surface and Said-Ball surface and includes several intermediate surfaces. To convert different bases and surfaces,the dual functionals of bases are presented. As an application of dual functionals,the subdivision formulas for surfaces are established.
基金supported by Ministry of Science and InnovationNational Research Agency(Project PID2019-105960RBC21)+1 种基金by the Basque Government(Project IT1509-2022)One of the authors(JAOC)acknowledges the post-doctoral research grant(DOCREC20/49)provided by the University of the Basque Country。
文摘Integrated CO_(2)capture and utilization(ICCU)technology requires dual functional materials(DFMs)to carry out the process in a single reaction system.The influence of the calcination atmosphere on efficiency of 4%Ru-8%Na_(2)CO_(3)-8%CaO/γ-Al_(2)O_(3)DFM is studied.The adsorbent precursors are first co-impregnated onto alumina and calcined in air.Then,Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols:static air in muffle or under different mixtures(10%H_(2)/N_(2),50%H_(2)/N_(2)and N_(2))streams.Samples are characterized by XRD,N_(2)adsorption-desorption,H_(2)chemisorption,TEM,XPS,H_(2)-TPD,H_(2)-TPR,CO_(2)-TPD and TPSR.The catalytic behavior is evaluated,in cycles of CO_(2)adsorption and hydrogenation to CH_(4),and temporal evolution of reactants and products concentrations is analyzed.The calcination atmosphere influences the physicochemical properties and,ultimately,activity of DFMs.Characterization data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic activity.DFM calcined under N_(2)flow(RuNaCa-N_(2))shows the highest CH_(4)production(449μmol/g at 370℃),because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases,maximizing the specific surface area,the Ru-basic sites interface and the participation of different basic sites in the CO_(2)methanation reaction.Thus,the calcination in a N_(2)flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO_(2)adsorption and hydrogenation applications.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 10171026, 60473114,and Anhui Provincial Natural Science Foundation under Grant No. 03046102.
文摘The generalized Ball curves of Wang-Said type with a position parameter L not only unify the Wang-Ball curves and the Said-Ball curves, but also include several useful intermediate curves. This paper presents the dual functionals for the generalized Ball basis of Wang-Said type. The relevant basis transformation formulae are also worked out.
基金financially supported by Shaanxi Province Key Research and Development Project(No.2024GX-YBXM-331)China Scholarship Council(No.CXXM20210077)+1 种基金the National Natural Science Foundation of China(No.22278260)Scientific Research Plan Projects of Shaanxi Education Department(No.24JC009).
文摘Flexible electronic devices are integral for meeting the diverse and complex requirements of wearable and multifunctional applications.Conductive papers with characteristics of light-weight,good processability,and degradability,offer significant benefits to wearable electronics.However,it often suffers from discontinuous distribution of the conductive network,inferior ductility,and conformability,which hinders its application.Herein,we present a conductive paper consisting of high-performance aramid paper as the matrix,and MXene and carbon nanotubes as the conductive fillers,fabricated through a mature papermaking technique and a kirigami design.The resultant dual functional kirigami paper(DFKP)exhibits desirable flexibility and breathability,excellent conductivity(1245.7 S/m),superior mechanical properties(tensile strength of 53.8 MPa),and ideal ductility(an elongation of~612.1%),demonstrating promising capabilities in simultaneously wearable motion-sensing and electrical thermotherapy applications.The DFKP enables flexible deformation,better skin attachment,and three-dimensional(3D)supports for precise monitoring of physiological changes in response to different motions,featuring rapid response and recovery times as short as 30 ms.Furthermore,it exhibits a rapid temperature increase and reaches 95.3℃within 35 s upon applying a voltage of 6 V.Remarkably,the DFKP proves stabilities under repeated deformations,maintaining a stable operational state even after 8000 cycles of stretching.Therefore,this unique wearable DFKP holds great promise for simultaneously being employed in human health monitoring and electrothermal therapy.
基金supported by the Shanghai Municipal Science and Technology Major Project,the SPIC-SJTU Joint Research Foundation for Future Energy Plan(No.110001JX0120240074)the Science and Technology Cooperation Project of Inner Mongolia Autonomous Region and Shanghai Jiao Tong University,China.
文摘Direct air capture(DAC)is an emerging technology aimed at mitigating global warming.However,conventional DAC technologies and the subsequent utilization processes are complex and energy-intensive.An integrated system of direct air capture and utilization(IDACU)via in-situ catalytic conversion to fuels and chemicals is a promising approach,although it remains in the early stages of development.This review examines the current technical routes of IDACU,including solid-based dual-functional materials(DFMs)through thermo-catalysis,IDACU using liquid sorbents with thermo-catalysis,and non-thermal conversion methods.It covers the basic principles,reaction conditions,main products,material types,and the existing problems and challenges associated with these technical routes.Additionally,it discusses the recent advancements in solid-based DFMs for IDACU,with particular attention to the differences in material characteristics between carbon capture from flue gases(ICCU)and DAC.While IDACU technology holds significant promise,it still faces numerous challenges,especially in the design of advanced materials.
基金supported by the National Natural Science Foundation of China (21966006)。
文摘A fluorescent active organic–inorganic hybrid material Py N-SBA-15 was synthesized by implementing pyrene derivatives into mesoporous SBA-15 silica.Py N-SBA-15 had detection and removal functionalities toward Al^(3+),Cu^(2+),and Hg^(2+).On the one hand,Py N-SBA-15 was used as a fluorescence sensor and displayed high sensitivity toward Al^(3+),Cu^(2+),and Hg^(2+)cations (limit of detection:8.0×10^(-7),1.1×10^(-7),and 2.9×10^(-6)mol·L^(–1),respectively) among various analytes with“turn-off”response.On the other hand,the adsorption studies for these toxic analytes (Cu^(2+),Hg^(2+),and Al^(3+)) showed that the ion removal capacity could reach up to 45,581,and 85 mg·g^(-1),respectively.Moreover,the Langmuir isotherm models were better fitted with the adsorption data,indicating that the adsorption was mono-layer adsorption.Kinetic analysis revealed that the adsorption process was well described by the pseudo-second-order kinetic model for Cu^(2+)and Hg^(2+)and pseudo-first-order kinetic model for Al^(3+).The prepared silica material could be reused in four recycles without significantly decreasing its adsorption capacity.Therefore,the Py N-SBA-15 material can serve as a promising candidate for the simultaneous rapid detection and efficient adsorption of metal ions.
基金This work was supported by the National Natural Science Foundation of China(21971262,92056201)the National Postdoctoral Program for Innovative Talents(BX20190399)+3 种基金Guangdong Provincial Key Laboratory of Chiral Molecule and Drug Discovery(2019B030301005)the National Mega-project for Innovative Drugs(2019ZX09721001-006-001)the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(2016ZT06Y337)the Fundamental Research Funds for the Central Universities(20ykpy113,18843407).
文摘An unprecedented gold-catalyzed ketene C=O/C=C bifunctionalization method has been developed.Mechanistic studies and density function theory(DFT)calculations indicate that the reaction is initiated by gold-catalyzed Wolff rearrangement of diazoketone to form the ketene intermediate,followed by intermolecular nucleophilic addition and terminated with two divergent cyclization processes via enol intermediates.In the case with alcohols as the nucleophiles,the reaction goes through a C-5-endodig carbocyclization to give the indene products;whereas,O-7-endo-dig cyclization occurs dominantly when indoles/pyrroles are used as the nucleophiles,delivering the 7-membered benzo[d]oxepines.In comparison with the well-documented cycloaddition and nucleophilic addition reactions,this cascade reaction features a novel reaction pattern for the ketene dual functionalization through addition with nucleophile and electrophile in sequence.
基金supported by the National Science Foundation of China (70771080)Social Science Foundation of Ministry of Education (10YJC630233)
文摘The penalty function method, presented many years ago, is an important nu- merical method for the mathematical programming problems. In this article, we propose a dual-relax penalty function approach, which is significantly different from penalty func- tion approach existing for solving the bilevel programming, to solve the nonlinear bilevel programming with linear lower level problem. Our algorithm will redound to the error analysis for computing an approximate solution to the bilevel programming. The error estimate is obtained among the optimal objective function value of the dual-relax penalty problem and of the original bilevel programming problem. An example is illustrated to show the feasibility of the proposed approach.
文摘Starting from the hydroxylamine (dimethyl amino ethanol, triethanolamine) and 1,3-propane sultone, a series of hydroxyl and sulfonyl dual-functionalized zwitterionic salts and corresponding acidic room temperature ionic liquids have been synthesized. The hydroxyl groups of the synthesized substances were confirmed by the 1H NMR measurement. These zwitterionic salts and ionic liquids may be used for synthesizing other functionalized ionic liquids or ionic liquid-polymer (polyelectrolyte).
文摘In this paper,we proved that the infinitesimal generator of a strongly continuous cosine operator function is preserved under the time-dependent perturbation in the sun-reflexive case,where the perturbed operator is a bounded linear operator from X into a bigger space Xθ(not X),then the corresponding 2-order abstract Cauchy problem is uniformly well-posed.
文摘The functionally graded thermal barrier coatings （FG-TBCs） with 80%ZrO2-13%CeO2-7%Y2O3 （C-YSZ）/NiCoCrAlY were prepared using a recently developed supersonic plasma spraying（S-PS） with dual powder feed ports system. The thermal shock experiment of FG-TBCs specimens was carried out by means of the automatic thermal cycle device, in which the samples were heated to 1200℃ by oxygen-acetylene flame jet then water-quenched to ambient temperature. The temperature—time curves of specimens and photographs can be watched on-line and recorded by a computer during the test. The results show that the totally 1mm-thick FG-TBCs have excellent thermal shock resistance due to the fact that the coatings have no any peeling-off after 200 thermal cycles. The microstructures and morphologies of FG-TBCs were characterized and analyzed by SEM.
基金supported by the National Natural Science Foundation of China(Nos. 21575168, 21475153,21575167 and 21675178)the Guangdong Provincial Natural Science Foundation of China(No. 2015A030311020)+1 种基金the Special Funds for Public Welfare Research and Capacity Building in Guangdong Province of China(No. 2015A030401036)the Guangzhou Science andTechnology Program of China(Nos.201604020165, 201704020040)
文摘Bisphenol A （BPA） was one of the environmental hormones that would cause endocrine and metabolic disorders in human or wildlife. This paper proposed a method to detect the trace amounts of BPA in water samples by fully utilizing the enrichment and resonance amplification functions of a new dual-functional membrane. In this work, gold nanoparticles （AuNPs） modified by 3-amino-5-mercapto-1,2,4-triazole （AMT） were embedded in nylon66 membrane to produce a dual-functional membrane which could carry out sample enrichment by capturing BPA molecules from water and achieve resonance amplification by connecting BPA to the surfaces of AuNPs. By designing an automatic sampler for large-volume enrichment, the SERS enhancement factor （EF） of the method was further improved to 1.2 × 105. The present method had been successfully applied to detect BPA in drinking water and environmental water by SERS with the detection limit of 0.012 μg/L. It had the potential for on-site detecting of BPA in various water samples.
文摘This article reports on the synthesis of acrylate monomer from renewable material. Vanillin was selected to be the start material to produce new monomer called vanillin acrylate and abbreviated by (VA). It has been successfully investigated by 1H, 13C NMR, IR and UV and all results were in logic state. The next step was to synthetize three different thermo-responsive functional copolymers by incorporation of three different molar ratios of vanillin acrylate (10, 20, 30 mol%) with N-Isopropylacrylamide via free radical polymerization by AIBN as initiator in solution. All copolymers were deduced by 1NMR and IR and all showed the presence of aldehyde group. The copolymer was used for grafting of tryptophan and β-alanine through the chemical link between amino group and the active aldehyde group by click reactions to form Schiff’s base imine compounds. Moreover, polymers were also elucidated by 1HNMR, IR and UV, Size Exclusion Chromatography (SEC) was used for the molecular weight determination, differential scanning calorimeter (DSC) for glass temperature of solid polymers, XRD for crystallinity. UV-vis Spectroscopy was used for the determination of phase separation or the lower critical solution temperature (Tc) of polymers solution not only in deionized water but in pH5 and pH11. The mount of conversation and linked amino acid was determined by UV-vis Spectroscopy.
文摘The present work is devoted to define a generalized Green’s function solution for the dual-phase-lag model in homogeneous materials in a unified manner .The high-order mixed derivative with respect to space and time which reflect the lagging behavior is treated in special manner in the dual-phase-lag heat equation in order to construct a general solution applicable to wide range of dual-phase-lag heat transfer problems of general initial-boundary conditions using Green’s function solution method. Also, the Green’s function for a finite medium subjected to arbitrary heat source and arbitrary initial and boundary conditions is constructed. Finally, four examples of different physical situations are analyzed in order to illustrate the accuracy and potentialities of the proposed unified method. The obtained results show good agreement with works of [1-4].
基金supported by a National Research Foundation of Korea Grant funded by the Korean Government,No.2009-0064682
文摘We performed functional MRI examinations in six right-handed healthy subjects.During functional MRI scanning,transcranial direct current stimulation was delivered with the anode over the right primary sensorimotor cortex and the cathode over the left primary sensorimotor cortex using dual-hemispheric transcranial direct current stimulation.This was compared to a cathode over the left supraorbital area using conventional single-hemispheric transcranial direct current stimulation. Voxel counts and blood oxygenation level-dependent signal intensities in the right primary sensorimotor cortex regions were estimated and compared between the two transcranial direct current stimulation conditions.Our results showed that dual-hemispheric transcranial direct current stimulation induced greater cortical activities than single-hemispheric transcranial direct current stimulation.These findings suggest that dual-hemispheric transcranial direct current stimulation may provide more effective cortical stimulation than single-hemispheric transcranial direct current stimulation.
