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1,n-Thiosulfonylation using thiosulfonates as dual functional reagents 被引量:1
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作者 Danhua Ge Jia-Wei Chen +2 位作者 Pei Xu Jinyin Pan Xue-Qiang Chu 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第11期4732-4739,共8页
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
关键词 Thiosulfonylation Thiosulfonates dual functional reagents Difunctionalization Atomic economy
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Bioactive glass sol as a dual function additive for chitosan-alginate hybrid scaffold 被引量:2
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作者 Huihui Ren Yang Cui +1 位作者 Ailing Li Dong Qiu 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第3期395-398,共4页
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
关键词 Bioactive glass sol Chitosan Alginate dual function additive Bioactivity
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DUAL FUNCTIONALS OF SAID-BZIER TYPE GENERALIZED BALL BASES OVER TRIANGLE DOMAIN AND THEIR APPLICATION
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作者 Wu Hongyi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第1期96-106,共11页
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
关键词 Bézier basis Said-Bézier type generalized Ball (SBGB) basis triangular domain dual functional subdivision formula.
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Enhancement of the CO_(2)adsorption and hydrogenation to CH_(4)capacity of Ru–Na–Ca/γ–Al_(2)O_(3)dual function material by controlling the Ru calcination atmosphere
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作者 Alejandro Bermejo-López Beñat Pereda-Ayo +2 位作者 Jon A.Onrubia-Calvo JoséA.González-Marcos Juan R.González-Velasco 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第6期292-305,共14页
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
关键词 CO_(2)methanation Integrated CO_(2)capture and utilization(ICCU) dual functional material(DFM) Ru calcination atmosphere
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The Dual Functionals for the Generalized Ball Basis of Wang-Said Type and Basis Transformation Formulas 被引量:2
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作者 Ping Jiang Hongyi Wu Jieqing Tan 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2006年第3期248-256,共9页
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
关键词 双功能 基本变形 算法 Wang-Said型 伯恩斯坦原理
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Bifurcated assembly pathway and dual function of a Lon-like protease revealed by cryo-EM Analysis
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作者 Ming Li Hongwei Liu +6 位作者 Kan-Yen Hsieh Shengchun Zhang Yongxiang Gao Qingguo Gong Kaiming Zhang Chung-I Chang Shanshan Li 《Fundamental Research》 2026年第2期879-884,共6页
The Lon proteases are evolutionarily conserved oligomeric hydrolases characterized by a built-in ATPase module.Here,we report the structures of LonC from Meiothermus taiwanensis(MtaLonC),a unique member in the Lon pro... The Lon proteases are evolutionarily conserved oligomeric hydrolases characterized by a built-in ATPase module.Here,we report the structures of LonC from Meiothermus taiwanensis(MtaLonC),a unique member in the Lon protein family with a dual chaperone-protease function but lacking ATPase activity,determined by cryo-electron microscopy(cryo-EM).In its apo state,LonC forms phosphate-bound open-ring pentamers,open-ring hexamers,and close-ring heptamers.However,upon interaction with ATPγS,inhibitor,or substrate,MtaLonC assembles into close-ring hexamers,wherein the protease domain’s substrate-binding loop adopts an extended active conformation.We show that proteolytic and chaperone activities may be carried out by the close-ring hexameric and heptameric forms,respectively.We further show that MtaLonC forms exclusively close-ring heptamers at elevated temperatures.This study sheds light on the bifurcated assembly pathway of MtaLonC,leading to two distinct oligomeric close-ring complexes that carry out a dual function. 展开更多
关键词 Lon-like protease CRYO-EM Assembly dual function Chaperone
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Dual functional kirigami paper for simultaneously motionmonitoring and electrothermal heating
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作者 Jiawei Liu Bin Yang +2 位作者 Hui Zhang Yonghao Ni Meiyun Zhang 《Nano Research》 2025年第6期545-556,共12页
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
关键词 aramid paper kirigami dual functional flexible sensor electrothermal heating
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Integrated direct air CO_(2)capture and utilization via in-situ catalytic conversion to fuels and chemicals using dual functional materials:Recent progresses and perspectives
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作者 Yiran Zhang Jiaqi Feng +4 位作者 Linjia Li Shu Zhao Chunfei Wu Zhen Huang He Lin 《Frontiers in Energy》 2025年第5期586-598,共13页
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
关键词 direct air capture(DAC) integrated carbon capture and utilization(ICCU) integrated direct air CO_(2)capture and utilization(IDACU) dual functional materials(DFMs) in-situ catalytic conversion
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Dual-functional pyrene implemented mesoporous silicon material used for the detection and adsorption of metal ions
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作者 Jing Huang Honghui Cai +3 位作者 Qian Zhao Yunpeng Zhou Haibo Liu Jing Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期108-117,共10页
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
关键词 dual function Nanomaterials Mesoporous silica Metal ions Detection and adsorption
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Gold-catalyzed ketene dual functionalization and mechanistic insights:divergent synthesis of indenes and benzo[d]oxepines
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作者 Ming Bao Jinzhou Chen +4 位作者 Chao Pei Sujie Zhang Jinping Lei Wenhao Hu Xinfang Xu 《Science China Chemistry》 SCIE EI CSCD 2021年第5期778-787,共10页
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
关键词 metal carbene ketene dual functionalization Wolff rearrangement gold catalysis INDENE benzo[d]oxepine
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A DUAL-RELAX PENALTY FUNCTION APPROACH FOR SOLVING NONLINEAR BILEVEL PROGRAMMING WITH LINEAR LOWER LEVEL PROBLEM 被引量:7
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作者 万仲平 王广民 吕一兵 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期652-660,共9页
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
关键词 Nonlinear bilevel programming penalty function approach dual-relax strategy
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Synthesis of multi-hydroxyl and sulfonyl dual-functionalized room temperature ionic liquids
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作者 Guo Yang Zhu Rong Wang +3 位作者 Guo Hua Liu Li Qun Xu Bei Zhang Xia Qin Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期633-635,共3页
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
关键词 dual-functionalized Zwitterionic salt Room temperature ionic liquids POLYMERIZATION
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Perturbation Theory for Dual Cosine Function(Ⅱ)—Time-dependent Perturbation in the Sun-reflexive Case
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作者 丁天彪 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第2期82-84,共3页
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
关键词 dual cosine operator function time-dependent perturbation θ-reflexivity
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Characterization of functionally graded ZrO_2 thermal barrier coatings sprayed by supersonic plasma spray with dual powder feed ports 被引量:1
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作者 韩志海 王海军 +1 位作者 周世魁 徐滨士 《Journal of Central South University》 SCIE EI CAS 2005年第S2期257-260,共4页
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
关键词 supersonic plasma spray (S-PS) dual powder feed ports functionally graded thermal barrier coatings (FG-TBCs) thermal shock
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A dual-functional membrane for bisphenol A enrichment and resonance amplification by surface-enhanced Raman scattering
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作者 Haoyu Lei Yuling Hu Gongke Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第3期509-512,共4页
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
关键词 dual-functional membrane Enrichment Resonance amplification Bisphenol A Surface-enhanced Raman scattering
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Poly (N-Isopropyl Acrylamide-<i>Co</i>-Vanillin Acrylate) Dual Responsive Functional Copolymers for Grafting Biomolecules by Schiff’s Base Click Reaction
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作者 Momen S. A. Abdelaty Dirk Kuckling 《Open Journal of Organic Polymer Materials》 2018年第2期15-32,共18页
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
关键词 dual RESPONSIVE POLYMERS functionAL POLYMERS GRAFTING Amino Acids Schiff’s Base Click Reactions
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Green’s Function Solution for the Dual-Phase-Lag Heat Equation
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作者 Reem Alkhairy 《Applied Mathematics》 2012年第10期1170-1178,共9页
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
关键词 dual-Phase-Lag HEAT Conduction Green’s function INTEGRAL Transforms
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Onsite-effects of dual-hemisphere versus conventional single-hemisphere transcranial direct current stimulation A functional MRI study
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作者 Yong Hyun Kwon Sung Ho Jang 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第24期1889-1894,共6页
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
关键词 transcranial direct current stimulation dual-hemispheric stimulation cortical activation functional MRI primary sensorimotor cortex NEUROIMAGING regeneration neural regeneration
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雷达通信一体化波形设计综述
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作者 唐波 吴文俊 +1 位作者 夏学成 王雄鹏 《国防科技大学学报》 北大核心 2026年第2期349-366,共18页
雷达通信一体化通过硬件资源共享与信号波形协同设计,突破传统分立架构下的频谱冲突、硬件冗余和电磁兼容性瓶颈,提升平台的综合作战效能与战场生存能力。系统回顾了雷达通信一体化技术从概念萌芽、架构演进到系统实现的发展历程,重点... 雷达通信一体化通过硬件资源共享与信号波形协同设计,突破传统分立架构下的频谱冲突、硬件冗余和电磁兼容性瓶颈,提升平台的综合作战效能与战场生存能力。系统回顾了雷达通信一体化技术从概念萌芽、架构演进到系统实现的发展历程,重点分析了基于线性调频、正交频分复用、正交时频空等主流信号体制的雷达通信一体化波形设计方法;深入探讨了以感知性能为中心的多种波形设计准则,包括方向图匹配、克拉美罗界优化及信息论方法等;梳理了从软件无线电兼容验证、机载多模态波形融合,到多节点与多域协同的工程实践之路,清晰展现了雷达通信一体化技术从理论到实践的演进路径。通过全面展示雷达通信一体化系统从常规体制到多输入多输出体制,再到原理样机验证的完整技术脉络,为未来雷达通信一体化技术的研究与开发提供系统的理论指导和实践参考。 展开更多
关键词 频谱共享 雷达通信一体化 波形设计 原型验证
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近红外脑功能成像分析脑力负荷双任务对前额叶皮质血液动力学的影响
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作者 郭振 李姝蕊 +2 位作者 郑伟薇 李若菲 李庆雯 《中国组织工程研究》 北大核心 2026年第25期6584-6591,共8页
背景:日常生活中,人们常处在同时执行运动和认知的双任务模式,这种情境需要协调运动和认知功能,对大脑工作负荷提出了更高的要求。理论上认知任务难度可对双任务表现产生影响,但目前对于不同脑力负荷下运动认知双任务中前额叶皮质血液... 背景:日常生活中,人们常处在同时执行运动和认知的双任务模式,这种情境需要协调运动和认知功能,对大脑工作负荷提出了更高的要求。理论上认知任务难度可对双任务表现产生影响,但目前对于不同脑力负荷下运动认知双任务中前额叶皮质血液动力学反应的变化机制尚不清楚。明确不同认知负荷下前额叶皮质的血液动力学反应,对于优化运动认知训练干预策略、提升训练效果及安全性具有重要意义。目的:通过使用便携式近红外脑功能成像装置,观察不同脑力负荷下窄距步行叠加逻辑减法的双任务对前额叶皮质血液动力学的影响。方法:招募大学生30名,随机顺序完成窄距步行、窄距步行&减3、窄距步行&减7三种任务条件。观察前额叶皮质氧合血红蛋白变化、主观认知负荷水平、双任务成本,并同步记录观察行为学步态时空参数。数据经Shapiro-Wilk检验后,使用Friedman检验及Wilcoxon检验分析前额叶皮质激活差异,重复测量方差分析比较认知负荷与步态表现,Pearson相关分析评估前额叶皮质激活与认知负荷关系。结果与结论:①与窄距步行相比,减3与减7双任务可显著增加前额叶皮质多通道激活(P<0.05),但背外侧前额叶皮质在减3任务下激活高于减7(P<0.05);②随着任务难度提升,正确率显著降低(P<0.01),且步长、支撑相、摆动相等步态参数进一步下降(P<0.05-0.01),双任务成本上升(P<0.01);③前额叶皮质显著激活通道与脑力需求、时间需求、努力程度、挫败感及总体任务负荷呈正相关,与任务绩效呈负相关;④提示双任务干预时选择适中的认知负荷有利于充分激活前额叶皮质资源而不过载,从而在认知任务和运动任务间取得较好的平衡;研究结果揭示了双任务中运动与认知的交互机制,为优化运动-认知双任务训练效果与安全性提供了科学支撑。 展开更多
关键词 运动-认知双任务 近红外脑功能成像 脑力负荷 前额叶皮质 脑血液动力学
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