We present an overview of some recent developments in the area of mathematical modeling of maintenance decisions for multi-unit systems. The emphasis is on three main groups of multicomponent maintenance optimization ...We present an overview of some recent developments in the area of mathematical modeling of maintenance decisions for multi-unit systems. The emphasis is on three main groups of multicomponent maintenance optimization models： the block replacement models, group maintenance models, and opportunistic maintenance models. Moreover, an example of a two-unit system maintenance process is provided in order to compare various maintenance policies.展开更多
The periodic precipitation occurs in a gel medium due to counter diffusion of ions,It is shown that the law derived earlier for double component systemcan be modified and found to be true in a multicomponent system.
Solid solutions(SS)of 3-and 4-component systems based on lead titanate-zirconate were prepared by the method of solid-phase reactions and uniaxial hot pressing.The dependences of the relative permittivity of polarized...Solid solutions(SS)of 3-and 4-component systems based on lead titanate-zirconate were prepared by the method of solid-phase reactions and uniaxial hot pressing.The dependences of the relative permittivity of polarized samples on the electronegativity(EN)of their constituent cations have been studied.The ferro-hardness of the SS(the stability of the domain structure to external influences)is shown to be directly dependent on the EN of elements B in the corresponding oxidation states,i.e.,the degree of covalence of the B-O bond.The deviation from this dependence in SS with Ni and Cd is explained by their individual features,which result in changes in the degree of bond covalence in both cationic sublattices.The conducted crystal-chemical analysis made it possible to choose promising SS when creating ferroelectric materials,including textured piezoelectric ceramic materials for piezoelectric transducers for various purposes:Piezotransformers,piezoelectric motors,ultrasonic emitters,filter devices,ultrasonic flaw detectors,accelerometers,etc.展开更多
Complex systems exist widely,including medicines from natural products,functional foods,and biological samples.The biological activity of complex systems is often the result of the synergistic effect of multiple compo...Complex systems exist widely,including medicines from natural products,functional foods,and biological samples.The biological activity of complex systems is often the result of the synergistic effect of multiple components.In the quality evaluation of complex samples,multicomponent quantitative analysis(MCQA)is usually needed.To overcome the difficulty in obtaining standard products,scholars have proposed achieving MCQA through the“single standard to determine multiple components(SSDMC)”approach.This method has been used in the determination of multicomponent content in natural source drugs and the analysis of impurities in chemical drugs and has been included in the Chinese Pharmacopoeia.Depending on a convenient(ultra)high-performance liquid chromatography method,how can the repeatability and robustness of the MCQA method be improved?How can the chromatography conditions be optimized to improve the number of quantitative components?How can computer software technology be introduced to improve the efficiency of multicomponent analysis(MCA)?These are the key problems that remain to be solved in practical MCQA.First,this review article summarizes the calculation methods of relative correction factors in the SSDMC approach in the past five years,as well as the method robustness and accuracy evaluation.Second,it also summarizes methods to improve peak capacity and quantitative accuracy in MCA,including column selection and twodimensional chromatographic analysis technology.Finally,computer software technologies for predicting chromatographic conditions and analytical parameters are introduced,which provides an idea for intelligent method development in MCA.This paper aims to provide methodological ideas for the improvement of complex system analysis,especially MCQA.展开更多
Embedding a third and/or fourth component into a binary blend active layer of organic photovoltaics (OPVs) is a promising approach to achieve high-performance photovoltaic cells and modules. This multicomponent strate...Embedding a third and/or fourth component into a binary blend active layer of organic photovoltaics (OPVs) is a promising approach to achieve high-performance photovoltaic cells and modules. This multicomponent strategy favors absorption broadening via additional components. Quaternary OPV (QOPV) blends have four components in three possible configurations: (i) a donor and three acceptors, (ii) two donors and two acceptors, or (iii) three donors and an acceptor. Although quaternary systems have only been relatively recently studied compared to other systems in OPVs, leveraging the synergistic effects of the four components leads to record power conversion efficiencies, currently approaching 20%. QOPVs provide ample material choices for compatibility and channels for charge transfer mechanisms, possibly leading to optimized morphology and orientation. Reviewing recent progress in advancing QOPVs is essential for understanding their contribution to the OPV field. The review mainly discusses research progress in QOPVs with a keen interest in their various configurations, semitransparency, and outdoor and indoor applications. It describes the not-well-understood QOPV's general working mechanism. This review explores high-performance QOPVs based on the fourth component's contribution as a donor, acceptor, or dye molecule and beyond in photovoltaic applications. Finally, there is a discussion around QOPV's outlook and projected future research directions in this field. This review intends to provide an overview of the quaternary systems approach to OPVs and inform current and future researchers on investigating the full spectrum of OPVs.展开更多
Three adsorption rate rnodels are derived for multicomponent adsorption systems under either pore diffusion or surface diffusion control. The linear driving force (LDF) model is obtained by assuming a parabolic intrap...Three adsorption rate rnodels are derived for multicomponent adsorption systems under either pore diffusion or surface diffusion control. The linear driving force (LDF) model is obtained by assuming a parabolic intraparticle concentration profile. Models Ⅰ and Ⅱ are obtained from the parabolic concentration layer approximation. Examples are presented to demonstrate the usage and accuracy of these models. It is shown that Model Ⅰ is suitable for batch adsorption calculations and Model Ⅱ provides a good approximation in fixed-bed adsorption pro-cesses while the LDF model should not be used in batch adsorption and may be considered acceptable in fixed-bed adsorption where the parameter Ti is relatively large.展开更多
This paper presents a set of multicomponent matrix Lie algebra, which is used to construct a new loop algebra A^-M. By using the Tu scheme, a Liouville integrable multicomponent equation hierarchy is generated, which ...This paper presents a set of multicomponent matrix Lie algebra, which is used to construct a new loop algebra A^-M. By using the Tu scheme, a Liouville integrable multicomponent equation hierarchy is generated, which possesses the Hamiltonian structure. As its reduction cases, the multicomponent （2＋1）-dimensional Glachette-Johnson （G J） hierarchy is given. Finally, the super-integrable coupling system of multicomponent （2＋1）-dimensional GJ hierarchy is established through enlarging the spectral problem.展开更多
Novel hydrogen storage materials have propelled progress in hydrogen storage technologies.Magnesium hydride(MgH_(2))is a highly promising candidate.Nevertheless,several drawbacks,including the need for elevated therma...Novel hydrogen storage materials have propelled progress in hydrogen storage technologies.Magnesium hydride(MgH_(2))is a highly promising candidate.Nevertheless,several drawbacks,including the need for elevated thermal conditions,sluggish dehydrogena-tion kinetics,and high thermodynamic stability,limit its practical application.One effective method of addressing these challenges is cata-lyst doping,which effectively boosts the hydrogen storage capability of Mg-based materials.Herein,we review recent advancements in catalyst-doped MgH_(2) composites,with particular focus on multicomponent and high-entropy catalysts.Structure-property relationships and catalytic mechanisms in these doping strategies are also summarized.Finally,based on existing challenges,we discuss future research directions for the development of Mg-based hydrogen storage systems.展开更多
Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structur...Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structural studies of other physicochemical properties are con-ducted on a series of materials obtained by the sol-gel method with different ratios of Gd and Sm cations.It is documented that changing the x value,and the resulting adjustment of the average ionic radius,have a significant impact on the crystal structure,stability,as well as on the total conductivity and thermomechanical properties of the materials,with the best results obtained for the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)composition.Oxygen electrodes are prepared using the selected compound,allowing to obtain low polarization resistance values,such as 0.086Ω·cm^(2)at 800℃.Systematic studies of electrocatalytic activity are conducted using La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(_(0.2))O_(3−δ)as the electrolyte for all electrodes,and Ce_(0.8)Gd_(0.2)O_(2−δ)electrolyte for the best performing Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes.The electrochemical data are analyzed using the distribution of relaxation times method.Also,the influence of the preparation method of the electrode material is in-ve`stigated using the electrospinning technique.Finally,the performance of the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes is tested in a Ni-YSZ(yttria-stabilized zirconia)anode-supported cell with a Ce_(0.8)Gd_(0.2)O_(2−δ)buffer layer,in the fuel cell and electrolyzer operating modes.With the electrospun electrode,a power density of 462 mW·cm^(−2)is obtained at 700℃,with a current density of ca.0.2 A·cm^(−2)at 1.3 V for the electrolysis at the same temperature,indicating better performance compared to the sol-gel-based electrode.展开更多
Multicomponent(Hf-Zr-Ta)B_(2)potentially provides improved ablation resistance compared with silicon-based ceramics.Here we deposited(Hf_(0.5-x/2)Zr_(0.5-x/2)Ta_(x))B_(2)(x=0,0.1,and 0.2)coatings onto C/C com-posites,...Multicomponent(Hf-Zr-Ta)B_(2)potentially provides improved ablation resistance compared with silicon-based ceramics.Here we deposited(Hf_(0.5-x/2)Zr_(0.5-x/2)Ta_(x))B_(2)(x=0,0.1,and 0.2)coatings onto C/C com-posites,and investigated their ablation behaviors under an oxyacetylene torch with a heat flux of 2.4 MW m^(-2).It was observed that the x=0.1 oxide scale bulged but was denser,and the x=0.2 oxide scale was blown away due to the formation of excessive liquid.Based on these findings,we further de-veloped a duplex(Hf-Zr-Ta)B_(2)coating that showed a linear recession rate close to zero(0.11μm s^(-1))after two 120-s ablation cycles.It is identified that the resulting oxide scale is mainly composed of(Hf,Zr)_(6)Ta_(2)O_(17)and(Hf,Zr,Ta)O_(2)by performing aberration-corrected(scanning)transmission electron microscopy.The protective mechanism is related to the peritectic transformation of orthorhombic-(Hf,Zr)_(6)Ta_(2)O_(17)to tetragonal-(Hf,Zr,Ta)O_(2)plus Ta-dominated liquid.This study contributes to the develop-ment of Ta-containing multicomponent UHTC bulk and coatings for ultra-high temperature applications.展开更多
Despite their attractive features of high energy density,low cost,and safety,polysulfide/iodide flow batteries(SIFBs)are hampered by the sluggish kinetics of the iodide redox couple,which restricts overall performance...Despite their attractive features of high energy density,low cost,and safety,polysulfide/iodide flow batteries(SIFBs)are hampered by the sluggish kinetics of the iodide redox couple,which restricts overall performance.Multicomponent sulfides are demonstrated as promising catalysts for accelerating I^(-)/I_(3)^(-) redox reactions.Concurrently,the enhanced configurational entropy arising from multinary compositions drives synergistic effects among constituent elements,establishing a viable pathway to optimize catalytic performance.Building on these foundations,this work introduces a targeted orbital hybridization-optimized electron density strategy to enhance the catalytic activity.Implementing this concept,we developed an in-situ solvothermal synthesis process for an entropy-enhanced AgCuZnSnS_(4) loaded graphite felt(ACZTS/GF)electrode.The engineered electrode demonstrates exceptional electrocatalytic performance with improved bulk conductivity and interfacial charge transfer kinetics within a SIFB.The cell achieves a high energy efficiency of 88.5%at 20 mA·cm^(−2) with 10%state-of-charge.Furthermore,the battery delivers a maximum power density of 119.8 mW·cm^(−2) and exhibits excellent long-term cycling stability.These significant results stem from orbital hybridization-driven electronic state optimization and entropy effect-induced synergistic catalysis.展开更多
Objectives:To assess the effects of a wearable-sensorassisted multicomponent exercise program on physical fitness,cognition and quality of life in a practical setting involving frail older adults.Methods:Frail older a...Objectives:To assess the effects of a wearable-sensorassisted multicomponent exercise program on physical fitness,cognition and quality of life in a practical setting involving frail older adults.Methods:Frail older adults(n=130)were randomly divided into a control(CG,n=68)group and an exercise group(EG,n=62)in a 12-week intervention,which included stride gait training with wearable sensors;aerobic exercise;and resistance,flexibility,balance,and cognitive training.Primary outcomes(physical fitness)were evaluated via the SPPB and SFT.Secondary outcomes(cognitive ability,quality of life and frailty)were evaluated via the MoCA-BC,SF-36 and Fried frailty criteria,respectively.Results:After the 12-week intervention,the EG demonstrated significant improvements(p<0.05)vs.the CG in gait speed(β_(3)=0.424,coefficient of interaction effect between group and time from the generalized linear mixed model),chair stand(β_(3)=0.501)and total score(β_(3)=65.466)of SPPB and all SFT components including 6MWT(walked distance,β_(3)=1.098;walking speed,β_(3)=0.105;stride length,β_(3)=0.041),back scratch(β_(3)=4.926),chair sit and reach(β_(3)=3.762),30s arm curl(β_(3)=6.124),30s sit-to-stand(β_(3)=3.04),and TUG(β_(3)=−6.712).The MoCA-BC total,verbal fluency and delayed recall scores;the physical function,general health,vitality,and mental health scores of the SF-36;and the frailty phenotype in the EG were significantly improved compared with those of the CG.Conclusions:The progressive wearable-sensor-assisted multicomponent exercise program designed in this study enhanced physical fitness,cognitive ability and quality of life and slowed down the progression of frailty in frail older adults,supporting its potential as a feasible communitybased health intervention.展开更多
We demonstrate a case study of Ce-doped yttrium aluminum garnet(YAG)phosphor to illustrate a novel plasma route for the synthesis of multicomponent materials with addressing morphology and structural control.The prese...We demonstrate a case study of Ce-doped yttrium aluminum garnet(YAG)phosphor to illustrate a novel plasma route for the synthesis of multicomponent materials with addressing morphology and structural control.The presented strategy was started directly from liquid precursors without any precipitating agents,and an innovative growth mechanism was proposed to explain the formation of monodispersed spherical particles with an adjusted size distribution.Homogeneous elemental distribution close to that of liquid precursors was also achieved due to the thermal nonequilibrium effect in plasma.Benefiting from the structural feature of the obtained product,a low transformation temperature of 1100℃for YAG phase was obtained and final products exhibit the highest photoluminescence intensity with rather low Ce doping of 0.5 wt.%,together with excellent thermal stability of 92%preservation of initial emission at 473 K.This work well illustrates the advance of plasma strategy in formation of multicomponent com-pounds with excellent performances,and its potential for large-scale production due to the transient and in-flight synthesis process.展开更多
Foreword It is our great privilege,as vip Editors of the International Journal of Minerals,Metallurgy and Materials(IJMMM),to present this special issue on“High-Entropy and Multicomponent-Doped Materials for Energy...Foreword It is our great privilege,as vip Editors of the International Journal of Minerals,Metallurgy and Materials(IJMMM),to present this special issue on“High-Entropy and Multicomponent-Doped Materials for Energy Applications:Innovations in Energy Conversion and Storage.”This collection highlights the latest research developments in the preparation,optimizing properties,and exploring potential applications of high-entropy materials(HEMs)and other com-pounds with increased configurational entropy.展开更多
Premature adiabatic shear localization caused by strain softening is a roadblock for the application of body-centered cubic(BCC)structured high-entropy alloy(HEAs)in the impact field.A micron-scale orthorhombic-phase(...Premature adiabatic shear localization caused by strain softening is a roadblock for the application of body-centered cubic(BCC)structured high-entropy alloy(HEAs)in the impact field.A micron-scale orthorhombic-phase(O-phase)strengthened TiZrVNbAl alloy was developed to delay adiabatic shear failure and enhance dynamic ductility.The O-phase can not only reduce the slip length,but also promote the pinning and tangling of the dislocations near the phase boundaries.The introduction of the O-phase transformed the strain hardening rate from negative to positive,resulting in a significantly improved dynamic shear resistance.Meanwhile,slip transfer across the O-phase via dislocation cutting mechanisms and a reduction of slip band spacing guaranteed dynamic deformation uniformity.Benefiting from the introduction of the O-phase,the alloy exhibits an excellent stored energy density(∼446 J/cm^(3),surpass the reported BCC-HEAs and typical titanium alloys),a large dynamic fracture strain(∼42%)and a considerable dynamic specific yield strength(∼241 MPa cm^(3)g^(-1)).The present study presents an effective approach for developing BCC-HEAs with excellent dynamic shear resistance and plasticity.展开更多
Bubbles are prevalent defects on the oxidized surfaces of ultra-high temperature carbides,compromis-ing structural stability and oxidation resistance.Despite their significance,the formation mechanisms and microstruct...Bubbles are prevalent defects on the oxidized surfaces of ultra-high temperature carbides,compromis-ing structural stability and oxidation resistance.Despite their significance,the formation mechanisms and microstructural evolution of bubbles during ultra-high temperature oxidation remain inadequately understood.To address this gap,the bubble behaviors of multicomponent carbides,including(Hf,Ti)C,(Hf,Zr,Ti)C,(Hf,Zr,Ti,Ta)C,and(Hf,Zr,Ti,Nb)C,were investigated under oxidation conditions at 2500℃.The roles of various elements were elucidated through first-principles calculations.Results show that the for-mation of a dense composite oxide layer is essential for bubble generation,with the release of gaseous products serving as the primary driving force.The microstructure of the bubbles is influenced by the ma-trix composition.The addition of Ti,Ta,and Nb significantly lowers the surface energy of the shell oxides,providing preferential nucleation sites for bubbles.The progressive oxidation of Ti leads to the formation of a“TiO_(2)-TiO-HfO_(2)”multilayerstructureat thebubbletop,which evolvesintoadendriticstructurewith prolonged oxidation.Ta and Nb further modulate the size and number of bubbles by altering the compo-sition and surface energy of the shell oxides.展开更多
Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great signif...Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance.In this work,trialdehydes,diamines,and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions,producing hyperbranched poly(α-aminonitrile)s with high molecular weights(M_(w) up to 4.87×10^(4))in good yields(up to 85%).The hyperbranched poly(α-aminonitrile)s have good solubility in commonly used organic solvents,high thermal stability as well as morphological stability.Furthermore,due to the numerous aldehyde groups in their branched chains,these hb-poly(α-aminonitrile)s can undergo one-pot,two-step,four-component post-polymerization with high efficiency.This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes,amines and trimethylsilyl cyanide,but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.展开更多
Exploration of new green polymerization strategies for the construction of conjugated polymers is important but challengeable.In this work,a multicomponent polymerization of acetylarenes,alkynones and ammonium acetate...Exploration of new green polymerization strategies for the construction of conjugated polymers is important but challengeable.In this work,a multicomponent polymerization of acetylarenes,alkynones and ammonium acetate for in situ construction of conjugated poly(triarylpyridine)s was developed.The polymerization reactions of diacetylarenes,aromatic dialkynones and NH_(4)OAc were performed in dimethylsulfoxide(DMSO)under heating in the presence of potassium tert-butoxide(t-BuOK),affording four conjugated poly(2,4,6-triarylpyridine)s(PTAPs)in satisfactory yields.The resulting PTAPs have good solubility in common organic solvents and high thermal stability with 5%weight loss temperatures reaching up to 460℃.They are also electrochemically active.The PTAPs incorporating tetraphenylethene units manifest aggregation-induced emission features.Moreover,through simply being doped into poly(vinyl alcohol)(PVA)matrix,the polymer and model compound containing triphenylamine moieties exhibit room-temperature phosphorescence properties with ultralong lifetimes up to 696.2 ms and high quantum yields up to 28.7%.This work not only provides a facile green synthetic route for conjugated polymers but also offers new insights into the design of advanced materials with unique photophysical properties.展开更多
With the evolution of nickel-based single crystal superalloys,there is an increase in heavy elements such as Re and Ru.This has made solutal convection more pronounced during the directional solidification process,lea...With the evolution of nickel-based single crystal superalloys,there is an increase in heavy elements such as Re and Ru.This has made solutal convection more pronounced during the directional solidification process,leading to solute redistribution and increasing the risk of casting defects such as low-angle grain boundaries.To avoid casting defects,downward directional solidification(DWS)method is adopted to eliminate solutal convection and change solute redistribution.However,there is currently no in-situ characterization or quantitative simulation studying the solute redistribution during DWS and upward directional solidification(UWS)processes.A multicomponent phase field simulation coupled with lattice Boltzmann method was employed to quantitatively investigate changes in dendrite morphology,solutal convection and deviation of dendrite tips from the perspective of solute redistribution during UWS and DWS processes.The simulation of microstructure agrees well with the experimental results.The mechanism that explains how solutal convection affects side branching behavior is depicted.A novel approach is introduced to characterize dendrite deviation,elucidating the reasons why defects are prone to occur under the influence of natural convection and solute redistribution.展开更多
Face-centered cubic(FCC)-structured multicomponent alloys typically exhibit good ductility but low strength.To simultaneously improve strength and ductility,a multicomponent alloy,Ni_(43.9)Co_(22.4)Fe_(8.8)Al_(10.7)Ti...Face-centered cubic(FCC)-structured multicomponent alloys typically exhibit good ductility but low strength.To simultaneously improve strength and ductility,a multicomponent alloy,Ni_(43.9)Co_(22.4)Fe_(8.8)Al_(10.7)Ti_(11.7)B_(2.5)(at%)with a unique microstructure was developed in this work.The microstructure,which includes 17.8%nanosized L12 precipitates and 26.6%micron-sized annealing twins distributed within~8μm fine FCC grains,was achieved through cryogenic rolling and subsequent annealing.The alloy exhibits a yield strength(YS)of 1063 MPa,ultimate tensile strength(UTS)of 1696 MPa,and excellent elongation of~26%.The L1_(2) precipitates and high-density grain boundaries act as a barrier to the dislocation movement,resulting in a substantial strengthening effect.In addition,the dislocations can cut through the L1_(2) precipitates that are coherent with the FCC matrix,whereas the twin boundaries can effectively absorb and store dislocations,leading to a high work-hardening rate.Furthermore,the stacking faults,Lomer-Cottrell locks,and 9-layer rhombohedral stacking sequence(9R)structures formed during tensile deformation significantly enhance strain hardening by blocking dislocation movement and accumulating dislocations,resulting in excellent comprehensive tensile properties.Theoretical calculations reveal that the grain boundaries,L1_(2)precipitates,and twin boundaries contribute the strengths of 263.8,412.6,and 68.7 MPa,respectively,accounting for 71.9%of the YS.This study introduces a promising strategy for developing multicomponent alloys with significant strength-ductility synergies.展开更多
文摘We present an overview of some recent developments in the area of mathematical modeling of maintenance decisions for multi-unit systems. The emphasis is on three main groups of multicomponent maintenance optimization models： the block replacement models, group maintenance models, and opportunistic maintenance models. Moreover, an example of a two-unit system maintenance process is provided in order to compare various maintenance policies.
文摘The periodic precipitation occurs in a gel medium due to counter diffusion of ions,It is shown that the law derived earlier for double component systemcan be modified and found to be true in a multicomponent system.
基金This study was financially supported by the Ministry of Science and Higher Education of the Russian Federation(State task in the field of scientific activity,scientific project No.(0852-2020-0032)/(BAZ0110/20-3-07IF))This report is presented at the 10th Anniversary International Conference on“Physics and Mechanics of New Materials and Their Applications”(PHENMA 2021),Divnomorsk,Russia,May 23-27,2022.
文摘Solid solutions(SS)of 3-and 4-component systems based on lead titanate-zirconate were prepared by the method of solid-phase reactions and uniaxial hot pressing.The dependences of the relative permittivity of polarized samples on the electronegativity(EN)of their constituent cations have been studied.The ferro-hardness of the SS(the stability of the domain structure to external influences)is shown to be directly dependent on the EN of elements B in the corresponding oxidation states,i.e.,the degree of covalence of the B-O bond.The deviation from this dependence in SS with Ni and Cd is explained by their individual features,which result in changes in the degree of bond covalence in both cationic sublattices.The conducted crystal-chemical analysis made it possible to choose promising SS when creating ferroelectric materials,including textured piezoelectric ceramic materials for piezoelectric transducers for various purposes:Piezotransformers,piezoelectric motors,ultrasonic emitters,filter devices,ultrasonic flaw detectors,accelerometers,etc.
基金the National Natural Science Foundation of China(Grant No.:81803734)National S&T Major Special Project for New Innovative Drugs Sponsored(Grant No.:2019ZX09201005).
文摘Complex systems exist widely,including medicines from natural products,functional foods,and biological samples.The biological activity of complex systems is often the result of the synergistic effect of multiple components.In the quality evaluation of complex samples,multicomponent quantitative analysis(MCQA)is usually needed.To overcome the difficulty in obtaining standard products,scholars have proposed achieving MCQA through the“single standard to determine multiple components(SSDMC)”approach.This method has been used in the determination of multicomponent content in natural source drugs and the analysis of impurities in chemical drugs and has been included in the Chinese Pharmacopoeia.Depending on a convenient(ultra)high-performance liquid chromatography method,how can the repeatability and robustness of the MCQA method be improved?How can the chromatography conditions be optimized to improve the number of quantitative components?How can computer software technology be introduced to improve the efficiency of multicomponent analysis(MCA)?These are the key problems that remain to be solved in practical MCQA.First,this review article summarizes the calculation methods of relative correction factors in the SSDMC approach in the past five years,as well as the method robustness and accuracy evaluation.Second,it also summarizes methods to improve peak capacity and quantitative accuracy in MCA,including column selection and twodimensional chromatographic analysis technology.Finally,computer software technologies for predicting chromatographic conditions and analytical parameters are introduced,which provides an idea for intelligent method development in MCA.This paper aims to provide methodological ideas for the improvement of complex system analysis,especially MCQA.
基金the support of the research commission of the Catholic University of Lille and its Foundationthe IEMN laboratory for the financial supportsupport from the Materials Research Institute (MRI) and the Institute of Energy and the Environment (IEE) of the Pennsylvania State University。
文摘Embedding a third and/or fourth component into a binary blend active layer of organic photovoltaics (OPVs) is a promising approach to achieve high-performance photovoltaic cells and modules. This multicomponent strategy favors absorption broadening via additional components. Quaternary OPV (QOPV) blends have four components in three possible configurations: (i) a donor and three acceptors, (ii) two donors and two acceptors, or (iii) three donors and an acceptor. Although quaternary systems have only been relatively recently studied compared to other systems in OPVs, leveraging the synergistic effects of the four components leads to record power conversion efficiencies, currently approaching 20%. QOPVs provide ample material choices for compatibility and channels for charge transfer mechanisms, possibly leading to optimized morphology and orientation. Reviewing recent progress in advancing QOPVs is essential for understanding their contribution to the OPV field. The review mainly discusses research progress in QOPVs with a keen interest in their various configurations, semitransparency, and outdoor and indoor applications. It describes the not-well-understood QOPV's general working mechanism. This review explores high-performance QOPVs based on the fourth component's contribution as a donor, acceptor, or dye molecule and beyond in photovoltaic applications. Finally, there is a discussion around QOPV's outlook and projected future research directions in this field. This review intends to provide an overview of the quaternary systems approach to OPVs and inform current and future researchers on investigating the full spectrum of OPVs.
基金Supported by the National Natural Science Foundation of China (No. 30070636).
文摘Three adsorption rate rnodels are derived for multicomponent adsorption systems under either pore diffusion or surface diffusion control. The linear driving force (LDF) model is obtained by assuming a parabolic intraparticle concentration profile. Models Ⅰ and Ⅱ are obtained from the parabolic concentration layer approximation. Examples are presented to demonstrate the usage and accuracy of these models. It is shown that Model Ⅰ is suitable for batch adsorption calculations and Model Ⅱ provides a good approximation in fixed-bed adsorption pro-cesses while the LDF model should not be used in batch adsorption and may be considered acceptable in fixed-bed adsorption where the parameter Ti is relatively large.
基金supported by the National Key Basic Research Development of China (Grant No 2004CB318000)
文摘This paper presents a set of multicomponent matrix Lie algebra, which is used to construct a new loop algebra A^-M. By using the Tu scheme, a Liouville integrable multicomponent equation hierarchy is generated, which possesses the Hamiltonian structure. As its reduction cases, the multicomponent （2＋1）-dimensional Glachette-Johnson （G J） hierarchy is given. Finally, the super-integrable coupling system of multicomponent （2＋1）-dimensional GJ hierarchy is established through enlarging the spectral problem.
基金financially supported by the National Key Research and Development Program of China (No. 2021YFB4000604)the National Natural Science Foundation of China (No. 52271220)+2 种基金the 111 Project (No. B12015)the Fundamental Research Funds for the Central UniversitiesHaihe Laboratory of Sustainable Chemical Transformations, Guangxi Collaborative Innovation Centre of Structure and Property for New Energy and Materials, Science Research and Technology Development Project of Guilin (No. 20210102-4)
文摘Novel hydrogen storage materials have propelled progress in hydrogen storage technologies.Magnesium hydride(MgH_(2))is a highly promising candidate.Nevertheless,several drawbacks,including the need for elevated thermal conditions,sluggish dehydrogena-tion kinetics,and high thermodynamic stability,limit its practical application.One effective method of addressing these challenges is cata-lyst doping,which effectively boosts the hydrogen storage capability of Mg-based materials.Herein,we review recent advancements in catalyst-doped MgH_(2) composites,with particular focus on multicomponent and high-entropy catalysts.Structure-property relationships and catalytic mechanisms in these doping strategies are also summarized.Finally,based on existing challenges,we discuss future research directions for the development of Mg-based hydrogen storage systems.
基金funded by the National Science Centre,Poland,on the basis of the decision number UMO-2020/37/B/ST8/02097supported by the program“Excellence Initiative-Research University”for the AGH University of Krakow(IDUB AGH,No.501.696.7996,Action 4,ID 9880).
文摘Multicomponent Gd_(1−x)Sm_(x)Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)double perovskites are optimized for application in terms of chemical composi-tion and morphology for the use as oxygen electrodes in solid oxide cells.Structural studies of other physicochemical properties are con-ducted on a series of materials obtained by the sol-gel method with different ratios of Gd and Sm cations.It is documented that changing the x value,and the resulting adjustment of the average ionic radius,have a significant impact on the crystal structure,stability,as well as on the total conductivity and thermomechanical properties of the materials,with the best results obtained for the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)composition.Oxygen electrodes are prepared using the selected compound,allowing to obtain low polarization resistance values,such as 0.086Ω·cm^(2)at 800℃.Systematic studies of electrocatalytic activity are conducted using La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(_(0.2))O_(3−δ)as the electrolyte for all electrodes,and Ce_(0.8)Gd_(0.2)O_(2−δ)electrolyte for the best performing Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes.The electrochemical data are analyzed using the distribution of relaxation times method.Also,the influence of the preparation method of the electrode material is in-ve`stigated using the electrospinning technique.Finally,the performance of the Gd_(0.75)Sm_(0.2)5Ba_(0.5)Sr_(0.5)CoCuO_(5+δ)electrodes is tested in a Ni-YSZ(yttria-stabilized zirconia)anode-supported cell with a Ce_(0.8)Gd_(0.2)O_(2−δ)buffer layer,in the fuel cell and electrolyzer operating modes.With the electrospun electrode,a power density of 462 mW·cm^(−2)is obtained at 700℃,with a current density of ca.0.2 A·cm^(−2)at 1.3 V for the electrolysis at the same temperature,indicating better performance compared to the sol-gel-based electrode.
基金supported by the National Key R&D Pro-gram of China(Grant No.2021YFA0715803)the National Natural Science Foundation of China(Grant Nos.52293373,52130205,and 52302091)+1 种基金the Joint Fund of Henan Province Science and Technol-ogy R&D Program(No.225200810002)the ND Basic Research Funds of Northwestern Polytechnical University(No.G2022WD).
文摘Multicomponent(Hf-Zr-Ta)B_(2)potentially provides improved ablation resistance compared with silicon-based ceramics.Here we deposited(Hf_(0.5-x/2)Zr_(0.5-x/2)Ta_(x))B_(2)(x=0,0.1,and 0.2)coatings onto C/C com-posites,and investigated their ablation behaviors under an oxyacetylene torch with a heat flux of 2.4 MW m^(-2).It was observed that the x=0.1 oxide scale bulged but was denser,and the x=0.2 oxide scale was blown away due to the formation of excessive liquid.Based on these findings,we further de-veloped a duplex(Hf-Zr-Ta)B_(2)coating that showed a linear recession rate close to zero(0.11μm s^(-1))after two 120-s ablation cycles.It is identified that the resulting oxide scale is mainly composed of(Hf,Zr)_(6)Ta_(2)O_(17)and(Hf,Zr,Ta)O_(2)by performing aberration-corrected(scanning)transmission electron microscopy.The protective mechanism is related to the peritectic transformation of orthorhombic-(Hf,Zr)_(6)Ta_(2)O_(17)to tetragonal-(Hf,Zr,Ta)O_(2)plus Ta-dominated liquid.This study contributes to the develop-ment of Ta-containing multicomponent UHTC bulk and coatings for ultra-high temperature applications.
基金supported by the National Natural Science Foundation of China(Nos.22171180,22461142137,and 22478242)the Shanghai Municipal Science and Technology Major Project,China.
文摘Despite their attractive features of high energy density,low cost,and safety,polysulfide/iodide flow batteries(SIFBs)are hampered by the sluggish kinetics of the iodide redox couple,which restricts overall performance.Multicomponent sulfides are demonstrated as promising catalysts for accelerating I^(-)/I_(3)^(-) redox reactions.Concurrently,the enhanced configurational entropy arising from multinary compositions drives synergistic effects among constituent elements,establishing a viable pathway to optimize catalytic performance.Building on these foundations,this work introduces a targeted orbital hybridization-optimized electron density strategy to enhance the catalytic activity.Implementing this concept,we developed an in-situ solvothermal synthesis process for an entropy-enhanced AgCuZnSnS_(4) loaded graphite felt(ACZTS/GF)electrode.The engineered electrode demonstrates exceptional electrocatalytic performance with improved bulk conductivity and interfacial charge transfer kinetics within a SIFB.The cell achieves a high energy efficiency of 88.5%at 20 mA·cm^(−2) with 10%state-of-charge.Furthermore,the battery delivers a maximum power density of 119.8 mW·cm^(−2) and exhibits excellent long-term cycling stability.These significant results stem from orbital hybridization-driven electronic state optimization and entropy effect-induced synergistic catalysis.
基金supported by the project of Guangzhou Sports Science and Technology Collaborative Innovation Center(No.SL2022B04J00034)National Key Research and Development Program of China(No.2020YFC2002900)。
文摘Objectives:To assess the effects of a wearable-sensorassisted multicomponent exercise program on physical fitness,cognition and quality of life in a practical setting involving frail older adults.Methods:Frail older adults(n=130)were randomly divided into a control(CG,n=68)group and an exercise group(EG,n=62)in a 12-week intervention,which included stride gait training with wearable sensors;aerobic exercise;and resistance,flexibility,balance,and cognitive training.Primary outcomes(physical fitness)were evaluated via the SPPB and SFT.Secondary outcomes(cognitive ability,quality of life and frailty)were evaluated via the MoCA-BC,SF-36 and Fried frailty criteria,respectively.Results:After the 12-week intervention,the EG demonstrated significant improvements(p<0.05)vs.the CG in gait speed(β_(3)=0.424,coefficient of interaction effect between group and time from the generalized linear mixed model),chair stand(β_(3)=0.501)and total score(β_(3)=65.466)of SPPB and all SFT components including 6MWT(walked distance,β_(3)=1.098;walking speed,β_(3)=0.105;stride length,β_(3)=0.041),back scratch(β_(3)=4.926),chair sit and reach(β_(3)=3.762),30s arm curl(β_(3)=6.124),30s sit-to-stand(β_(3)=3.04),and TUG(β_(3)=−6.712).The MoCA-BC total,verbal fluency and delayed recall scores;the physical function,general health,vitality,and mental health scores of the SF-36;and the frailty phenotype in the EG were significantly improved compared with those of the CG.Conclusions:The progressive wearable-sensor-assisted multicomponent exercise program designed in this study enhanced physical fitness,cognitive ability and quality of life and slowed down the progression of frailty in frail older adults,supporting its potential as a feasible communitybased health intervention.
基金supported by the National Natu-ral Science Foundation of China(No.52174342)the Beijing Nat-ural Science Foundation(No.2232044)the Beijing Munic-ipal Education Commission Research Plan General Project(No.KM202410005009).
文摘We demonstrate a case study of Ce-doped yttrium aluminum garnet(YAG)phosphor to illustrate a novel plasma route for the synthesis of multicomponent materials with addressing morphology and structural control.The presented strategy was started directly from liquid precursors without any precipitating agents,and an innovative growth mechanism was proposed to explain the formation of monodispersed spherical particles with an adjusted size distribution.Homogeneous elemental distribution close to that of liquid precursors was also achieved due to the thermal nonequilibrium effect in plasma.Benefiting from the structural feature of the obtained product,a low transformation temperature of 1100℃for YAG phase was obtained and final products exhibit the highest photoluminescence intensity with rather low Ce doping of 0.5 wt.%,together with excellent thermal stability of 92%preservation of initial emission at 473 K.This work well illustrates the advance of plasma strategy in formation of multicomponent com-pounds with excellent performances,and its potential for large-scale production due to the transient and in-flight synthesis process.
文摘Foreword It is our great privilege,as vip Editors of the International Journal of Minerals,Metallurgy and Materials(IJMMM),to present this special issue on“High-Entropy and Multicomponent-Doped Materials for Energy Applications:Innovations in Energy Conversion and Storage.”This collection highlights the latest research developments in the preparation,optimizing properties,and exploring potential applications of high-entropy materials(HEMs)and other com-pounds with increased configurational entropy.
基金supported by the YEQISUN Joint Funds of the National Natural Science Foundation of China(Grant No.U2241234)the National Natural Science Foundation of China(Grant No.52301127).
文摘Premature adiabatic shear localization caused by strain softening is a roadblock for the application of body-centered cubic(BCC)structured high-entropy alloy(HEAs)in the impact field.A micron-scale orthorhombic-phase(O-phase)strengthened TiZrVNbAl alloy was developed to delay adiabatic shear failure and enhance dynamic ductility.The O-phase can not only reduce the slip length,but also promote the pinning and tangling of the dislocations near the phase boundaries.The introduction of the O-phase transformed the strain hardening rate from negative to positive,resulting in a significantly improved dynamic shear resistance.Meanwhile,slip transfer across the O-phase via dislocation cutting mechanisms and a reduction of slip band spacing guaranteed dynamic deformation uniformity.Benefiting from the introduction of the O-phase,the alloy exhibits an excellent stored energy density(∼446 J/cm^(3),surpass the reported BCC-HEAs and typical titanium alloys),a large dynamic fracture strain(∼42%)and a considerable dynamic specific yield strength(∼241 MPa cm^(3)g^(-1)).The present study presents an effective approach for developing BCC-HEAs with excellent dynamic shear resistance and plasticity.
基金financially supported by National Natural Science Foundation of China(No.52072410).
文摘Bubbles are prevalent defects on the oxidized surfaces of ultra-high temperature carbides,compromis-ing structural stability and oxidation resistance.Despite their significance,the formation mechanisms and microstructural evolution of bubbles during ultra-high temperature oxidation remain inadequately understood.To address this gap,the bubble behaviors of multicomponent carbides,including(Hf,Ti)C,(Hf,Zr,Ti)C,(Hf,Zr,Ti,Ta)C,and(Hf,Zr,Ti,Nb)C,were investigated under oxidation conditions at 2500℃.The roles of various elements were elucidated through first-principles calculations.Results show that the for-mation of a dense composite oxide layer is essential for bubble generation,with the release of gaseous products serving as the primary driving force.The microstructure of the bubbles is influenced by the ma-trix composition.The addition of Ti,Ta,and Nb significantly lowers the surface energy of the shell oxides,providing preferential nucleation sites for bubbles.The progressive oxidation of Ti leads to the formation of a“TiO_(2)-TiO-HfO_(2)”multilayerstructureat thebubbletop,which evolvesintoadendriticstructurewith prolonged oxidation.Ta and Nb further modulate the size and number of bubbles by altering the compo-sition and surface energy of the shell oxides.
基金financially supported by the Scientific Research Start-up Fund Project of Anhui Polytechnic University for Introducing Talents(No.2022YQQ081)Natural Science Research Project of Anhui Educational Committee(No.2024AH050133)the National Natural Science Foundation of China(No.22001078).
文摘Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse areas.Therefore,the development of simple and efficient reactions to prepare hyperbranched polymers is of great significance.In this work,trialdehydes,diamines,and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions,producing hyperbranched poly(α-aminonitrile)s with high molecular weights(M_(w) up to 4.87×10^(4))in good yields(up to 85%).The hyperbranched poly(α-aminonitrile)s have good solubility in commonly used organic solvents,high thermal stability as well as morphological stability.Furthermore,due to the numerous aldehyde groups in their branched chains,these hb-poly(α-aminonitrile)s can undergo one-pot,two-step,four-component post-polymerization with high efficiency.This work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes,amines and trimethylsilyl cyanide,but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.
基金supported by the National Natural Science Foundation of China(No.22071166)the Priority Academic Program Development of Jiangsu High Education Institutions(PAPD).
文摘Exploration of new green polymerization strategies for the construction of conjugated polymers is important but challengeable.In this work,a multicomponent polymerization of acetylarenes,alkynones and ammonium acetate for in situ construction of conjugated poly(triarylpyridine)s was developed.The polymerization reactions of diacetylarenes,aromatic dialkynones and NH_(4)OAc were performed in dimethylsulfoxide(DMSO)under heating in the presence of potassium tert-butoxide(t-BuOK),affording four conjugated poly(2,4,6-triarylpyridine)s(PTAPs)in satisfactory yields.The resulting PTAPs have good solubility in common organic solvents and high thermal stability with 5%weight loss temperatures reaching up to 460℃.They are also electrochemically active.The PTAPs incorporating tetraphenylethene units manifest aggregation-induced emission features.Moreover,through simply being doped into poly(vinyl alcohol)(PVA)matrix,the polymer and model compound containing triphenylamine moieties exhibit room-temperature phosphorescence properties with ultralong lifetimes up to 696.2 ms and high quantum yields up to 28.7%.This work not only provides a facile green synthetic route for conjugated polymers but also offers new insights into the design of advanced materials with unique photophysical properties.
基金supported by the stable support project and the Major National Science and Technology Project(2017-VII-0008-0101).
文摘With the evolution of nickel-based single crystal superalloys,there is an increase in heavy elements such as Re and Ru.This has made solutal convection more pronounced during the directional solidification process,leading to solute redistribution and increasing the risk of casting defects such as low-angle grain boundaries.To avoid casting defects,downward directional solidification(DWS)method is adopted to eliminate solutal convection and change solute redistribution.However,there is currently no in-situ characterization or quantitative simulation studying the solute redistribution during DWS and upward directional solidification(UWS)processes.A multicomponent phase field simulation coupled with lattice Boltzmann method was employed to quantitatively investigate changes in dendrite morphology,solutal convection and deviation of dendrite tips from the perspective of solute redistribution during UWS and DWS processes.The simulation of microstructure agrees well with the experimental results.The mechanism that explains how solutal convection affects side branching behavior is depicted.A novel approach is introduced to characterize dendrite deviation,elucidating the reasons why defects are prone to occur under the influence of natural convection and solute redistribution.
基金supported by the Major Science and Technology Project of Gansu Province(Nos.23ZDGA010 and 22ZD6GA008)the National Natural Science Foundation of China(No.51564035).
文摘Face-centered cubic(FCC)-structured multicomponent alloys typically exhibit good ductility but low strength.To simultaneously improve strength and ductility,a multicomponent alloy,Ni_(43.9)Co_(22.4)Fe_(8.8)Al_(10.7)Ti_(11.7)B_(2.5)(at%)with a unique microstructure was developed in this work.The microstructure,which includes 17.8%nanosized L12 precipitates and 26.6%micron-sized annealing twins distributed within~8μm fine FCC grains,was achieved through cryogenic rolling and subsequent annealing.The alloy exhibits a yield strength(YS)of 1063 MPa,ultimate tensile strength(UTS)of 1696 MPa,and excellent elongation of~26%.The L1_(2) precipitates and high-density grain boundaries act as a barrier to the dislocation movement,resulting in a substantial strengthening effect.In addition,the dislocations can cut through the L1_(2) precipitates that are coherent with the FCC matrix,whereas the twin boundaries can effectively absorb and store dislocations,leading to a high work-hardening rate.Furthermore,the stacking faults,Lomer-Cottrell locks,and 9-layer rhombohedral stacking sequence(9R)structures formed during tensile deformation significantly enhance strain hardening by blocking dislocation movement and accumulating dislocations,resulting in excellent comprehensive tensile properties.Theoretical calculations reveal that the grain boundaries,L1_(2)precipitates,and twin boundaries contribute the strengths of 263.8,412.6,and 68.7 MPa,respectively,accounting for 71.9%of the YS.This study introduces a promising strategy for developing multicomponent alloys with significant strength-ductility synergies.
