Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam...Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.展开更多
The sodium-iodine(Na-I)battery exhibits significant potential as an alternative energy storage device to the lithium-ion battery.However,its development is hindered by inadequate electrical and thermal stability,as we...The sodium-iodine(Na-I)battery exhibits significant potential as an alternative energy storage device to the lithium-ion battery.However,its development is hindered by inadequate electrical and thermal stability,as well as the dissolution and shuttling of polyiodide.In this study,we report a preparation method for melamine carbon sponge(MC)via carbonizing a commercially available kitchen sponge.It was revealed that the as-prepared MC,composed of unique self-growing carbon nanotubes,could provide both physical and chemical adsorption capabilities for intermediate polyiodides to improve the electrochemical performance of NaI.Consequently,the NaI/MC electrode effectively minimized polyiodide dissolution and reduced the electrochemical impedance.The NaI/MC cathode demonstrated a high average discharge capacity of 92.75 mAh·g^(–1)over 200 cycles while maintaining a coulombic efficiency of 94%.The research findings from our study have promising applications in Na-I batteries.展开更多
Magnesium and magnesium-based alloy hydrides remain attractive hydrogen storage materials owing to high hydrogen capacity and rich reserves in the earth＇s crust. A high stability of hydride and sluggish hydriding/deh...Magnesium and magnesium-based alloy hydrides remain attractive hydrogen storage materials owing to high hydrogen capacity and rich reserves in the earth＇s crust. A high stability of hydride and sluggish hydriding/dehydriding kinetics at practical temperatures for the materials drove researchers into alloying with other elements, using different preparation techniques, using catalyst and thin film hydride to improve the hydrogen absorption/desorption properties. In this review, the development of these approaches and their effects on the thermodynamic and kinetics properties of magnesium and magnesium-based alloy hydrides were descript in details.展开更多
After being activated,TiFe alloys are widely concerned for their high hydrogen storage density due to their large reversible absorption and desorption capacity of hydrogen at room temperature,low price,abundant resour...After being activated,TiFe alloys are widely concerned for their high hydrogen storage density due to their large reversible absorption and desorption capacity of hydrogen at room temperature,low price,abundant resources,moderate hydride decomposition pressure,and good hydrogen absorption and desorption kinetic performance.Meanwhile,TiFe alloys can be used as anode materials for secondary batteries,catalysts for hydrogenation,and storage media for thermal,solar,and wind energy,which has wide industrial application prospects.However,TiFe alloys have disadvantages such as difficult activation,easy toxicity,and large hysteresis.This review introduces the current research status and performance characteristics of TiFe-based hydrogen storage alloys,the phase structure,hydride phase structure,kinetic and thermodynamic models of TiFe alloys,as well as the application prospects of TiFe-based hydrogen storage alloys in practical production and the ways to improve their hydrogen storage performance,and presents the views on the future research priorities and development directions of TiFe-based hydrogen storage alloys.展开更多
Rare earth permanent magnetic materials are typical electrical conductor, and their magnetic properties will decrease because of the eddy current effect, so it is difficult to keep them stable for a long enough time u...Rare earth permanent magnetic materials are typical electrical conductor, and their magnetic properties will decrease because of the eddy current effect, so it is difficult to keep them stable for a long enough time under a high frequency AC field. In the present study, as far as rare earth permanent magnets are concerned, for the first time, rare earth permanent magnets with strong electrical insulation and high magnetic performance have been obtained through experiments, and their properties are as follows： （i） Sm1 TM17 ： Br=0. 62 T, jHc=803.7 kA/m, （BH）m= 58.97 kJ/m^3, p=7 Ω· m; （2） NdFeB： Br=0.485 T, jHc=766.33 kA/m, （BH）m=37.96 kJ/m^3, ρ=Ω · m. The magnetic properties of Sm2TM17 and NdFeB are obviously higher than those of ferrite permanent magnet, and the electric insulating characteristics of Sm2TM17 and NdFeB applied have in fact been approximately the same as those of ferrite. Therefore, Sm2TM17 and NdFeB will possess the ability to take the place of ferrite under a certain high frequency AC electric field.展开更多
Ti–Mn-based hydrogen storage alloys are considered to be one of the most promising hydrogen storage alloys for proton exchange membrane fuel cell applications,because of their good hydrogen absorption and desorption ...Ti–Mn-based hydrogen storage alloys are considered to be one of the most promising hydrogen storage alloys for proton exchange membrane fuel cell applications,because of their good hydrogen absorption and desorption kinetics,low price,good activation performance,possession of high electrochemical capacity,and good cycling performance.The structure,performance characteristics,crystal structure of hydrides,development and application status of Ti–Mn-based hydrogen storage alloys were reviewed,and the methods to improve Ti–Mn-based hydrogen storage alloys were discussed:optimization of the preparation process,element substitution,and surface treatment.(1)In the study of the alloy preparation process,it was found that the use of the annealing process can significantly improve the high rate discharge performance,and cycling stability performance,increasing the maximum discharge capacity of the alloy electrode.In addition,using vacuum plasma spraying to prepare the electrode has better cycling stability and kinetic performance.(2)In element substitution,the effects of using Zr elements to partially replace Ti and Mn with Cr,V,Mo,and Fe on the hydrogen storage properties of Ti–Mn-based alloys were investigated.(3)In the study of surface treatment,palladium was plated on the surface of TiMn_(1.5) alloy by chemical deposition,and the strong affinity of palladium for hydrogen accelerated the cleavage of hydrogen molecules,which significantly improved the hydrogen absorption kinetics of TiMn_(1.5) alloy.Meanwhile,a new binary alloy system was formed by adding TiMn_(2) to MgH_(2),and it was shown that the addition of TiMn_(2) significantly improved the hydrogen absorption/desorption kinetics of the MgH_(2) alloy.Finally,the prospect of the application of Ti–Mn-based hydrogen storage alloys is presented,and the insight of further development of the alloy is offered.展开更多
Ion transport plays an important role in energy conversion, biosensors, and a variety of biological processes. Carbon nanotubes, especially for the carbon nanotubes arrays with controlled vertically aligned structures...Ion transport plays an important role in energy conversion, biosensors, and a variety of biological processes. Carbon nanotubes, especially for the carbon nanotubes arrays with controlled vertically aligned structures, have displayed great potential as a promising material for regulating ion transport behaviors in the applications of the nanofluidic devices and osmotic energy conversion. Herein, we demonstrate the thermo-controlled ion transport system through the vertically aligned multiwall carbon nanotubes arrays membrane modified by the thermo-responsive hydrogel in a simple and reliable way. The functional carbon nanotubes backbone with the inherent surface charge and interstitial channels structure renders the system improved ion transport behaviors and well controlled switching property by thermo. Based on the integrated properties, the energy output from osmotic power in this system could be regulated by the reversible temperature switches. Moreover, it can realize a higher osmotic energy conversion property regulated by the thermos, which may extend the practical application in the future. The system that combines intelligent response with controlled ion transport behaviors and potential osmotic energy utilizations presents a valuable paradigm for the use of carbon nanotubes and hydrogel composite materials and provides a promising way for applications of nanofluidic devices.展开更多
Optoelectronic memristor is generating growing research interest for high efficient computing and sensing-memory applications.In this work,an optoelectronic memristor with Au/a-C:Te/Pt structure is developed.Synaptic ...Optoelectronic memristor is generating growing research interest for high efficient computing and sensing-memory applications.In this work,an optoelectronic memristor with Au/a-C:Te/Pt structure is developed.Synaptic functions,i.e.,excita-tory post-synaptic current and pair-pulse facilitation are successfully mimicked with the memristor under electrical and optical stimulations.More importantly,the device exhibited distinguishable response currents by adjusting 4-bit input electrical/opti-cal signals.A multi-mode reservoir computing(RC)system is constructed with the optoelectronic memristors to emulate human tactile-visual fusion recognition and an accuracy of 98.7%is achieved.The optoelectronic memristor provides potential for developing multi-mode RC system.展开更多
To address the challenges posed by high reaction temperatures and the slow kinetics of Mg-based alloys with high hydrogen storage density,Mg−RE−TM(RE=rare earth,TM=metallic element)alloys have been extensively researc...To address the challenges posed by high reaction temperatures and the slow kinetics of Mg-based alloys with high hydrogen storage density,Mg−RE−TM(RE=rare earth,TM=metallic element)alloys have been extensively researched and hold great promise.In this study,a series of Mg−RE−TM based Mg_(90)Y_(2)Ce_(2)Ni_(3)Al_(3-x)Sc_(x)(x=0,0.3,0.6,0.9,1.2)alloys were prepared.The addition of Sc element has been found to enhance the activation and kinetic properties of the alloy.Compared with the significant differences in the first four dehydrogenation curves of the Sc0 sample,the first activated dehydrogenation curve of the Sc1.2 alloy overlaps with the fully activated dehydrogenation curve.The dehydrogenation activation energy decreased from 96.56 kJ/mol in the Sc0 alloy to 63.69 kJ/mol in the Sc0.9 alloy.Through analysis of the microstructure,phase composition,and hydrogen absorption and desorption kinetics of the alloy,the mechanisms for improving the hydrogen storage properties of the alloy were elucidated.The nucleation-growth-impingement Avrami model was employed to accurately simulate the hydrogen storage kinetics.The results showed that stage II was prolonged and accelerated at high temperature,and the growth rate and hydrogen storage of stage I were increased at low temperature in hydrogen absorption.Microstructure analysis revealed the presence of Mg,CeMg_(12),Mg_(47)Y,and YNi_(2)Al_(3) phases in the Sc0 sample.Upon the addition of Sc element,a new phase,ScNiAl,was formed,and the coarse grain size of the main phase was significantly refined.This refinement provides faster diffusion channels for hydrogen atoms,accelerating the phase transition between Mg alloys and hydrides.The microstructure changes explain the improved activation properties,effective hydrogen absorption and desorption capacity,and kinetic properties of the Mg-based samples.展开更多
Rare earth(RE)elements have been successfully utilized in solid-state hydrogen storage as hydrogen-absorbing elements with excellent hydrogen storage properties in terms of safety and efficiency.RE-Mg-based hydrogen s...Rare earth(RE)elements have been successfully utilized in solid-state hydrogen storage as hydrogen-absorbing elements with excellent hydrogen storage properties in terms of safety and efficiency.RE-Mg-based hydrogen storage materials with high magnesium content are considered to be one of the most promising hydrogen storage materials for application due to their high mass/volume hydrogen storage density,moderate required hydrogen pressure,good reversibility,non-toxicity,and harmlessness.Furthermore,RE-Mg-based materials with low magnesium content and superlattice structure show great potential for application in the field of solid-state hydrogen storage.They are also widely used as anode materials for nickel-metal hydride batteries.In this paper,we comprehensively summarized and evaluated the organization and hydrogen storage properties of different RE-Mg system alloys(Mg-RE,Mg-RE-TM(TM=transition metals),and superlattice-type RE-Mg-TM)and the catalytic effect and mechanisms of catalysts on RE-Mg system alloys.The interactions between the types of RE elements,the contents of RE elements,the crystal structures,and the catalysts with the microstructure morphology and hydrogen storage properties of RE-Mg-based hydrogen storage alloys were established.The intrinsic mechanisms between microstructure morphology,phase structure,phase composition,and hydrogen storage properties of alloys with different RE-Mg-based systems were elucidated.By comparing the differences and characteristics between the organizational structures and hydrogen storage properties of different RE-Mg systems,a feasible idea and solution for the rational design and development of RE-Mg-based alloys with high hydrogen storage capacity,low cost,and fast hydrogen absorption and desorption kinetics was proposed.展开更多
In this work,a small amount of Al_(2)O_(3)powders(≤0.3 wt%)were incorporated into the Sm_(2)Co_(17)-type sin-tered magnets,obtaining both high mechanical and magnetic properties.It is found that 0.1%weight percentage...In this work,a small amount of Al_(2)O_(3)powders(≤0.3 wt%)were incorporated into the Sm_(2)Co_(17)-type sin-tered magnets,obtaining both high mechanical and magnetic properties.It is found that 0.1%weight percentage of Al_(2)O_(3)doping is enough to enhance the flexural strength by about 20%(∼180 MPa for the case of the c-axis parallel to height).Meanwhile,the(BH)max remains around 219 kJ/m^(3),and Hcj is 2052 kA/m,which is over 95%of that of the original magnets without doping.The promising improvement in flexural strength is mainly attributed to the grain size effective refinement caused by Sm_(2)O_(3)particles including newly-formed ones from the reaction of the Al_(2)O_(3)powder and Sm in the matrix.Furthermore,the grain size of the magnets decreases significantly with increasing of Al_(2)O_(3)doping up to 0.3 wt%.Espe-cially,the grain size of 0.3 wt%Al_(2)O_(3)doped magnets is refined by 37%.However,the flexural strengths(for the c-axis parallel to height and the c-axis parallel to width cases)of the magnets decrease sequen-tially and are even lower than that of the original magnet.The microstructure investigations indicate that the decrease in flexural strength may closely be correlated to the larger cell size and the incomplete cell boundaries phase.The obtained results infer that the flexural strength is susceptible to not only grain size but also the cellular structure of the magnets.展开更多
Rare earth-based Bi_(0.85)La_(0.15)FeO_(3)(BLFO)and NdMnO_(3)(NMO)particles were synthesised using the solidstate route,and their roles affecting structural,electrical,magnetic properties along with hydroelectric appl...Rare earth-based Bi_(0.85)La_(0.15)FeO_(3)(BLFO)and NdMnO_(3)(NMO)particles were synthesised using the solidstate route,and their roles affecting structural,electrical,magnetic properties along with hydroelectric application in different concentrations i.e.,(1-x)BLFO:xNMO(where x=0,0.10,0.20,0.30 and 1.0)ceramics composites were investigated.X-ray diffraction analyses confirm the pure-phase formation of BLFO:NMO composites,featuring micrometer-scale crystallite sizes.Fourier transform infrared(FT-IR)spectra of BLFO:NMO composites reveal peak shifts with rising NMO content,indicating composite formation.These composites exhibit robust Maxwell-Wagner polarization and a pronounced composition-dependent behavior.The addition of NMO to BLFO results in a rise in dielectric permittivity at lower frequencies,confirming relaxor behavior and indicating success in achieving the transition temperature.Impedance spectroscopy facilitates a clearer understanding of how charge carriers contribute to these composites and the impact of grain/grain boundaries.The saturation magnetization maximum value(i.e.,0.807 emu/g)was attained in 0.7BLFO-0.3NMO.The coercivity decreases with the addition of NMO in BLFO.The results suggest the composite's enhanced suitability for microelectronics and hydropower cells,showing improved hydroelectric cell performance with increased NMO in BLFO,highlighting a notable ion diffusion mechanism.展开更多
The elastic properties of membranes are typically characterized by a few phenomenological parameters,including bending and Gaussian curvature moduli measuring the membrane rigidity against its deformation and topologi...The elastic properties of membranes are typically characterized by a few phenomenological parameters,including bending and Gaussian curvature moduli measuring the membrane rigidity against its deformation and topological change,as well as spontaneous curvature arising from the asymmetry between the two leaflets in the lipid bilayers.Though tether-based and fluctuationbased experiments are commonly utilized to measure the bending modulus,measuring the Gaussian curvature modulus and the spontaneous curvature of the membrane is considered to be much more difficult.In this paper,we study the buckling process of a circular membrane with nonzero spontaneous curvature under compressive stresses.It is found that when the stress exceeds a critical value,the circular membrane will transform from a spherical cap to a buckled shape,with its buckling degree enhanced with the increase of stress until its base is constricted to almost zero.As the stress-strain relationship of the buckled membrane strongly depends on the Gaussian curvature modulus and the spontaneous curvature,we therefore propose a method to determine the Gaussian curvature modulus and the spontaneous curvature simultaneously by measuring its stress-strain relationship during a buckling process.展开更多
Spectrin domains,characterized by a distinctive triple helix structure,are crucial in physiological processes,particularly in maintaining membrane shape and crosslinking cytoskeletons.Previous research on the 16th dom...Spectrin domains,characterized by a distinctive triple helix structure,are crucial in physiological processes,particularly in maintaining membrane shape and crosslinking cytoskeletons.Previous research on the 16th domain of a-spectrin repeats(R16)has yielded conflicting results:bulk experiments showed an unfolding rate approximately two orders of magnitude faster than the zero-force result extrapolated from single-molecule force spectroscopy experiments using atomic force microscopy(AFM).To address this discrepancy,we investigated the folding and unfolding rates of R16 across a broader range of forces using magnetic tweezers(MT).Our findings reveal that AFM results at higher forces cannot be directly extrapolated to the low-force regime due to a nonlinear relationship between force and the logarithm of the unfolding rate.We demonstrated that two-dimensional model,structural-elastic model,and two-pathway model can all effectively explain the experimental data when they capture the core physics of the short unfolding distance at low forces.Our study provides a more comprehensive understanding of the unfolding dynamics of the spectrin domain,resolves previous contradictory experimental results,and highlights the common basis of different theoretical models.展开更多
Cell division is a fundamental biological process in which a parent cell divides into two daughter cells.The cell cortex,a thin layer primarily composed of actin filaments and myosin motors beneath the plasma membrane...Cell division is a fundamental biological process in which a parent cell divides into two daughter cells.The cell cortex,a thin layer primarily composed of actin filaments and myosin motors beneath the plasma membrane,plays a critical role in ensuring proper cell division.In this study,we apply a hydrodynamic model to describe the actin cortex as an active nematic surface,incorporating orientational order arising from actin filament alignment and anisotropic active stress produced by myosin motors.By analyzing the linearized dynamics,we investigate how shape,flow,and stress regulators evolve over time when the surface deviates slightly from a sphere.Our findings reveal that the active alignment of actin filaments,often overlooked in previous studies,is crucial for successful division.Furthermore,we demonstrate that a cortical chiral flow naturally emerges as a consequence of this active alignment.Overall,our results provide a mechanistic explanation for key phenomena observed during cell division,offering new insights into the role of active stress and filament alignment in cortical dynamics.展开更多
The La_(1.7)Pr_(0.3)Mg_(16)Ni hydrogen storage alloy was prepared by medium-frequency induction melting,and then the composite hydrogen storage alloy powder of La_(1.7)Pr_(0.3)Mg_(16)Ni+x wt.%(x=0,2,4,and 6)graphene w...The La_(1.7)Pr_(0.3)Mg_(16)Ni hydrogen storage alloy was prepared by medium-frequency induction melting,and then the composite hydrogen storage alloy powder of La_(1.7)Pr_(0.3)Mg_(16)Ni+x wt.%(x=0,2,4,and 6)graphene was prepared by ball milling for 10 h.The effect of the addition of graphene on the activation and hydrogen de/absorption properties of La_(1.7)Pr_(0.3)Mg_(16)Ni alloy was studied.The result demonstrated that these composite alloys were composed of La_(2)Mg_(17),La_(2)Ni_(3),and Mg_(2)Ni phases.After saturated hydrogen absorption,it was composed of LaH_(3),Mg_(2)NiH_(4),and MgH_(2)phases,while during the dehydrogenation process,it was composed of LaH_(3),Mg,and Mg_(2)Ni phases.The addition of graphene can help get a more homogeneous granule after ball milling and accelerate the first activation of dehydrogenation/hydrogen absorption.The hydrogen release activation energy of the alloys first decreases and then increases as the graphene content increases from x=0 wt.%to x=6 wt.%.The minimum activation energy of the composite hydrogen storage alloy is 51.22 kJ mol^(-1) when x=4 wt.%.展开更多
Vesicles of lipid bilayer can adopt a variety of shapes due to different coating proteins.The ability of proteins to reshape membrane is typically characterized by inducing spontaneous curvature of the membrane at the...Vesicles of lipid bilayer can adopt a variety of shapes due to different coating proteins.The ability of proteins to reshape membrane is typically characterized by inducing spontaneous curvature of the membrane at the coated area.BAR family proteins are known to have a crescent shape and can induce membrane curvature along their concaved body axis but not in the perpendicular direction.We model this type of proteins as a rod-shaped molecule with an orientation and induce normal curvature along its orientation in the tangential plane of the membrane surface.We show how a ring of these proteins reshapes an axisymmetric vesicle when the protein curvature or orientation is varied.A discontinuous shape transformation from a protrusion shape without a neck to a one with a neck is found.Increasing the rigidity of the protein ring is able to smooth out the transition.Furthermore,we show that varying the protein orientation is able to induce an hourglass-shaped neck,which is significantly narrower than the reciprocal of the protein curvature.Our results offer a new angle to rationalize the helical structure formed by many proteins that carry out membrane fission functions.展开更多
Controllable liquid manipulation is of paramount scientific and technological importance in various fields,such as the chemical industry,biomedicine,and agricultural production.Magnetic actuation,characterized by rapi...Controllable liquid manipulation is of paramount scientific and technological importance in various fields,such as the chemical industry,biomedicine,and agricultural production.Magnetic actuation,characterized by rapid,contactless,and environmentally benign operation,has emerged as a promising approach for precise liquid control.However,conventional magnetic strategies typically govern droplet movement on open surfaces,facing limitations such as restricted liquid volumes,uncertain flow paths,and inevitable evaporation,thereby constraining their broader practical applications.Recently,a variety of magneticdriven strategies have been developed to dynamically regulate liquids within enclosed spaces,especially through physicochemical mechanisms.These approaches provide efficient control over liquid behavior by leveraging magnetically induced chemical changes,structural deformations,and dragging motions,opening new opportunities for flexible and versatile fluid management.This review explores the design and mechanisms of magneto-responsive confined interfaces for the manipulation of nonmagnetic liquids,highlighting key advancements and potential applications including liquid valves,liquid mixing,liquid flow regulation,and liquid pumping.Finally,the existing challenges and future prospects in this field are presented.展开更多
Compound eyes(CEs)that feature ultra-compact structures and extraordinary versatility have revealed great potential for cutting-edge applications.However,the optoelectronic integration of CEs with available photodetec...Compound eyes(CEs)that feature ultra-compact structures and extraordinary versatility have revealed great potential for cutting-edge applications.However,the optoelectronic integration of CEs with available photodetectors is still challenging because the planar charge-coupled device(CCD)/complementary metal oxide semiconductor(CMOS)detector cannot match the spatially distributed images formed by CE ommatidia.To reach this end,we report here the optoelectronic integration of CEs by manufacturing 3D nonuniform ommatidia for developing an ultra-compact on-chip camera.As a proof-of-concept,we fabricated microscale CEs with uniform and nonuniform ommatidia through femtosecond laser two-photon photopolymerization,and compared their focusing/imaging performance both theoretically and experimentally.By engineering the surface profiles of the ommatidia at different positions of the CE,the images formed by all the ommatidia can be tuned on a plane.In this way,the nonuniform CE can be directly integrated with a commercial CMOS photodetector,forming an ultra-compact CE camera.Additionally,we further combine the CE camera with a microfluidic chip,which can further serve as an on-chip microscopic monitoring system.We anticipate that such an ultra-compact CE camera may find broad applications in microfluidics,robotics,and micro-optics.展开更多
The development of next-generation electromagnetic wave(EMW)absorbers requires a shift in interface design.By employing hierarchical work function programming,we propose an approach to tune interfacial polarization dy...The development of next-generation electromagnetic wave(EMW)absorbers requires a shift in interface design.By employing hierarchical work function programming,we propose an approach to tune interfacial polarization dynamics.This method utilizes multi-gradient work functions to guide carrier migration and polarization effectively,thereby enhancing energy dissipation under alternating electromagnetic fields.Here,we constructed a 1T/2H-MoS_(2)/PPy/VS_(2) composite absorber with integrated gradient interfaces.The composite achieved a powerful absorption(RLmin)of-58.59 dB at 2.3 mm,and an effective absorption bandwidth(EAB)of 7.44 GHz at 2.5 mm,demonstrating improved broadband absorption.Radar cross-section(RCS)simulations show an EMW loss of-7.2 dB m^(2) at 0°,highlighting its potential for stealth and communication applications.This study introduces hierarchical work function programming as a promising strategy in EMW absorber design,contributing to advancements in material performance and functionality.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.52293472,22473096 and 22471164)。
文摘Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.
基金supported by Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive Application(Grant No.ZDSYS20220527171407017).
文摘The sodium-iodine(Na-I)battery exhibits significant potential as an alternative energy storage device to the lithium-ion battery.However,its development is hindered by inadequate electrical and thermal stability,as well as the dissolution and shuttling of polyiodide.In this study,we report a preparation method for melamine carbon sponge(MC)via carbonizing a commercially available kitchen sponge.It was revealed that the as-prepared MC,composed of unique self-growing carbon nanotubes,could provide both physical and chemical adsorption capabilities for intermediate polyiodides to improve the electrochemical performance of NaI.Consequently,the NaI/MC electrode effectively minimized polyiodide dissolution and reduced the electrochemical impedance.The NaI/MC cathode demonstrated a high average discharge capacity of 92.75 mAh·g^(–1)over 200 cycles while maintaining a coulombic efficiency of 94%.The research findings from our study have promising applications in Na-I batteries.
基金financially supported by the National Natural Science Foundation of China (Nos. 51161015 and 51371094)
文摘Magnesium and magnesium-based alloy hydrides remain attractive hydrogen storage materials owing to high hydrogen capacity and rich reserves in the earth＇s crust. A high stability of hydride and sluggish hydriding/dehydriding kinetics at practical temperatures for the materials drove researchers into alloying with other elements, using different preparation techniques, using catalyst and thin film hydride to improve the hydrogen absorption/desorption properties. In this review, the development of these approaches and their effects on the thermodynamic and kinetics properties of magnesium and magnesium-based alloy hydrides were descript in details.
基金National Natural Science Foundation of China(51761032)Natural Science Foundation of Inner Mongolia,China(No.2019BS05005)Inner Mongolia University of Science and Technology Innovation Fund-(2019QDL-B11).
文摘After being activated,TiFe alloys are widely concerned for their high hydrogen storage density due to their large reversible absorption and desorption capacity of hydrogen at room temperature,low price,abundant resources,moderate hydride decomposition pressure,and good hydrogen absorption and desorption kinetic performance.Meanwhile,TiFe alloys can be used as anode materials for secondary batteries,catalysts for hydrogenation,and storage media for thermal,solar,and wind energy,which has wide industrial application prospects.However,TiFe alloys have disadvantages such as difficult activation,easy toxicity,and large hysteresis.This review introduces the current research status and performance characteristics of TiFe-based hydrogen storage alloys,the phase structure,hydride phase structure,kinetic and thermodynamic models of TiFe alloys,as well as the application prospects of TiFe-based hydrogen storage alloys in practical production and the ways to improve their hydrogen storage performance,and presents the views on the future research priorities and development directions of TiFe-based hydrogen storage alloys.
基金Item Sponsored by Liaoning Provincial Natural Science Foundation (20071090)
文摘Rare earth permanent magnetic materials are typical electrical conductor, and their magnetic properties will decrease because of the eddy current effect, so it is difficult to keep them stable for a long enough time under a high frequency AC field. In the present study, as far as rare earth permanent magnets are concerned, for the first time, rare earth permanent magnets with strong electrical insulation and high magnetic performance have been obtained through experiments, and their properties are as follows： （i） Sm1 TM17 ： Br=0. 62 T, jHc=803.7 kA/m, （BH）m= 58.97 kJ/m^3, p=7 Ω· m; （2） NdFeB： Br=0.485 T, jHc=766.33 kA/m, （BH）m=37.96 kJ/m^3, ρ=Ω · m. The magnetic properties of Sm2TM17 and NdFeB are obviously higher than those of ferrite permanent magnet, and the electric insulating characteristics of Sm2TM17 and NdFeB applied have in fact been approximately the same as those of ferrite. Therefore, Sm2TM17 and NdFeB will possess the ability to take the place of ferrite under a certain high frequency AC electric field.
基金It is sincere thanks to the National Natural Science Foundations of China(Grant.Nos.51761032,51871125 and 51731002)for financial support of the work.
文摘Ti–Mn-based hydrogen storage alloys are considered to be one of the most promising hydrogen storage alloys for proton exchange membrane fuel cell applications,because of their good hydrogen absorption and desorption kinetics,low price,good activation performance,possession of high electrochemical capacity,and good cycling performance.The structure,performance characteristics,crystal structure of hydrides,development and application status of Ti–Mn-based hydrogen storage alloys were reviewed,and the methods to improve Ti–Mn-based hydrogen storage alloys were discussed:optimization of the preparation process,element substitution,and surface treatment.(1)In the study of the alloy preparation process,it was found that the use of the annealing process can significantly improve the high rate discharge performance,and cycling stability performance,increasing the maximum discharge capacity of the alloy electrode.In addition,using vacuum plasma spraying to prepare the electrode has better cycling stability and kinetic performance.(2)In element substitution,the effects of using Zr elements to partially replace Ti and Mn with Cr,V,Mo,and Fe on the hydrogen storage properties of Ti–Mn-based alloys were investigated.(3)In the study of surface treatment,palladium was plated on the surface of TiMn_(1.5) alloy by chemical deposition,and the strong affinity of palladium for hydrogen accelerated the cleavage of hydrogen molecules,which significantly improved the hydrogen absorption kinetics of TiMn_(1.5) alloy.Meanwhile,a new binary alloy system was formed by adding TiMn_(2) to MgH_(2),and it was shown that the addition of TiMn_(2) significantly improved the hydrogen absorption/desorption kinetics of the MgH_(2) alloy.Finally,the prospect of the application of Ti–Mn-based hydrogen storage alloys is presented,and the insight of further development of the alloy is offered.
基金supported by the National Natural Science Foundation of China (Nos. 21975209, 52025132 and 21621091)the National Key R&D Program of China (No. 2018YFA0209500)。
文摘Ion transport plays an important role in energy conversion, biosensors, and a variety of biological processes. Carbon nanotubes, especially for the carbon nanotubes arrays with controlled vertically aligned structures, have displayed great potential as a promising material for regulating ion transport behaviors in the applications of the nanofluidic devices and osmotic energy conversion. Herein, we demonstrate the thermo-controlled ion transport system through the vertically aligned multiwall carbon nanotubes arrays membrane modified by the thermo-responsive hydrogel in a simple and reliable way. The functional carbon nanotubes backbone with the inherent surface charge and interstitial channels structure renders the system improved ion transport behaviors and well controlled switching property by thermo. Based on the integrated properties, the energy output from osmotic power in this system could be regulated by the reversible temperature switches. Moreover, it can realize a higher osmotic energy conversion property regulated by the thermos, which may extend the practical application in the future. The system that combines intelligent response with controlled ion transport behaviors and potential osmotic energy utilizations presents a valuable paradigm for the use of carbon nanotubes and hydrogel composite materials and provides a promising way for applications of nanofluidic devices.
基金supported by the"Science and Technology Development Plan Project of Jilin Province,China"(Grant No.20240101018JJ)the Fundamental Research Funds for the Central Universities(Grant No.2412023YQ004)the National Natural Science Foundation of China(Grant Nos.52072065,52272140,52372137,and U23A20568).
文摘Optoelectronic memristor is generating growing research interest for high efficient computing and sensing-memory applications.In this work,an optoelectronic memristor with Au/a-C:Te/Pt structure is developed.Synaptic functions,i.e.,excita-tory post-synaptic current and pair-pulse facilitation are successfully mimicked with the memristor under electrical and optical stimulations.More importantly,the device exhibited distinguishable response currents by adjusting 4-bit input electrical/opti-cal signals.A multi-mode reservoir computing(RC)system is constructed with the optoelectronic memristors to emulate human tactile-visual fusion recognition and an accuracy of 98.7%is achieved.The optoelectronic memristor provides potential for developing multi-mode RC system.
基金National Natural Science Foundation of China(51871125)the Major Programs of Central Iron and Steel Research Institute(No.23020230ZD)for financial support of the work.
文摘To address the challenges posed by high reaction temperatures and the slow kinetics of Mg-based alloys with high hydrogen storage density,Mg−RE−TM(RE=rare earth,TM=metallic element)alloys have been extensively researched and hold great promise.In this study,a series of Mg−RE−TM based Mg_(90)Y_(2)Ce_(2)Ni_(3)Al_(3-x)Sc_(x)(x=0,0.3,0.6,0.9,1.2)alloys were prepared.The addition of Sc element has been found to enhance the activation and kinetic properties of the alloy.Compared with the significant differences in the first four dehydrogenation curves of the Sc0 sample,the first activated dehydrogenation curve of the Sc1.2 alloy overlaps with the fully activated dehydrogenation curve.The dehydrogenation activation energy decreased from 96.56 kJ/mol in the Sc0 alloy to 63.69 kJ/mol in the Sc0.9 alloy.Through analysis of the microstructure,phase composition,and hydrogen absorption and desorption kinetics of the alloy,the mechanisms for improving the hydrogen storage properties of the alloy were elucidated.The nucleation-growth-impingement Avrami model was employed to accurately simulate the hydrogen storage kinetics.The results showed that stage II was prolonged and accelerated at high temperature,and the growth rate and hydrogen storage of stage I were increased at low temperature in hydrogen absorption.Microstructure analysis revealed the presence of Mg,CeMg_(12),Mg_(47)Y,and YNi_(2)Al_(3) phases in the Sc0 sample.Upon the addition of Sc element,a new phase,ScNiAl,was formed,and the coarse grain size of the main phase was significantly refined.This refinement provides faster diffusion channels for hydrogen atoms,accelerating the phase transition between Mg alloys and hydrides.The microstructure changes explain the improved activation properties,effective hydrogen absorption and desorption capacity,and kinetic properties of the Mg-based samples.
基金supported by the National Natural Science Foundation of China(51871125)the Major Programs of Central Iron and Steel Research Institute(No.23020230ZD).
文摘Rare earth(RE)elements have been successfully utilized in solid-state hydrogen storage as hydrogen-absorbing elements with excellent hydrogen storage properties in terms of safety and efficiency.RE-Mg-based hydrogen storage materials with high magnesium content are considered to be one of the most promising hydrogen storage materials for application due to their high mass/volume hydrogen storage density,moderate required hydrogen pressure,good reversibility,non-toxicity,and harmlessness.Furthermore,RE-Mg-based materials with low magnesium content and superlattice structure show great potential for application in the field of solid-state hydrogen storage.They are also widely used as anode materials for nickel-metal hydride batteries.In this paper,we comprehensively summarized and evaluated the organization and hydrogen storage properties of different RE-Mg system alloys(Mg-RE,Mg-RE-TM(TM=transition metals),and superlattice-type RE-Mg-TM)and the catalytic effect and mechanisms of catalysts on RE-Mg system alloys.The interactions between the types of RE elements,the contents of RE elements,the crystal structures,and the catalysts with the microstructure morphology and hydrogen storage properties of RE-Mg-based hydrogen storage alloys were established.The intrinsic mechanisms between microstructure morphology,phase structure,phase composition,and hydrogen storage properties of alloys with different RE-Mg-based systems were elucidated.By comparing the differences and characteristics between the organizational structures and hydrogen storage properties of different RE-Mg systems,a feasible idea and solution for the rational design and development of RE-Mg-based alloys with high hydrogen storage capacity,low cost,and fast hydrogen absorption and desorption kinetics was proposed.
基金supported by the National Key Research and Development Program of China(Nos.2021YFB3503100,2022YFB3505303,2021YFB3501500)the Major Projects in the Inner Mongolia Autonomous Region of China.
文摘In this work,a small amount of Al_(2)O_(3)powders(≤0.3 wt%)were incorporated into the Sm_(2)Co_(17)-type sin-tered magnets,obtaining both high mechanical and magnetic properties.It is found that 0.1%weight percentage of Al_(2)O_(3)doping is enough to enhance the flexural strength by about 20%(∼180 MPa for the case of the c-axis parallel to height).Meanwhile,the(BH)max remains around 219 kJ/m^(3),and Hcj is 2052 kA/m,which is over 95%of that of the original magnets without doping.The promising improvement in flexural strength is mainly attributed to the grain size effective refinement caused by Sm_(2)O_(3)particles including newly-formed ones from the reaction of the Al_(2)O_(3)powder and Sm in the matrix.Furthermore,the grain size of the magnets decreases significantly with increasing of Al_(2)O_(3)doping up to 0.3 wt%.Espe-cially,the grain size of 0.3 wt%Al_(2)O_(3)doped magnets is refined by 37%.However,the flexural strengths(for the c-axis parallel to height and the c-axis parallel to width cases)of the magnets decrease sequen-tially and are even lower than that of the original magnet.The microstructure investigations indicate that the decrease in flexural strength may closely be correlated to the larger cell size and the incomplete cell boundaries phase.The obtained results infer that the flexural strength is susceptible to not only grain size but also the cellular structure of the magnets.
基金Project supported by Research Scheme(03(1427)/18/EMR-Ⅱ),Council of Scientific&Industrial Research CSIR,New Delhi,IndiaUniversity Grants Commission-Department of Atomic Energy Consortium for Scientific Research UGC-DAE CSR-Indore,India。
文摘Rare earth-based Bi_(0.85)La_(0.15)FeO_(3)(BLFO)and NdMnO_(3)(NMO)particles were synthesised using the solidstate route,and their roles affecting structural,electrical,magnetic properties along with hydroelectric application in different concentrations i.e.,(1-x)BLFO:xNMO(where x=0,0.10,0.20,0.30 and 1.0)ceramics composites were investigated.X-ray diffraction analyses confirm the pure-phase formation of BLFO:NMO composites,featuring micrometer-scale crystallite sizes.Fourier transform infrared(FT-IR)spectra of BLFO:NMO composites reveal peak shifts with rising NMO content,indicating composite formation.These composites exhibit robust Maxwell-Wagner polarization and a pronounced composition-dependent behavior.The addition of NMO to BLFO results in a rise in dielectric permittivity at lower frequencies,confirming relaxor behavior and indicating success in achieving the transition temperature.Impedance spectroscopy facilitates a clearer understanding of how charge carriers contribute to these composites and the impact of grain/grain boundaries.The saturation magnetization maximum value(i.e.,0.807 emu/g)was attained in 0.7BLFO-0.3NMO.The coercivity decreases with the addition of NMO in BLFO.The results suggest the composite's enhanced suitability for microelectronics and hydropower cells,showing improved hydroelectric cell performance with increased NMO in BLFO,highlighting a notable ion diffusion mechanism.
基金the financial support from the National Natural Science Foundation of China under Grant Nos.12174323 and 12474199Fundamental Research Funds for Central Universities of China under Grant No.20720240144(RM)111 project B16029。
文摘The elastic properties of membranes are typically characterized by a few phenomenological parameters,including bending and Gaussian curvature moduli measuring the membrane rigidity against its deformation and topological change,as well as spontaneous curvature arising from the asymmetry between the two leaflets in the lipid bilayers.Though tether-based and fluctuationbased experiments are commonly utilized to measure the bending modulus,measuring the Gaussian curvature modulus and the spontaneous curvature of the membrane is considered to be much more difficult.In this paper,we study the buckling process of a circular membrane with nonzero spontaneous curvature under compressive stresses.It is found that when the stress exceeds a critical value,the circular membrane will transform from a spherical cap to a buckled shape,with its buckling degree enhanced with the increase of stress until its base is constricted to almost zero.As the stress-strain relationship of the buckled membrane strongly depends on the Gaussian curvature modulus and the spontaneous curvature,we therefore propose a method to determine the Gaussian curvature modulus and the spontaneous curvature simultaneously by measuring its stress-strain relationship during a buckling process.
基金supported by the National Natural Science Foun-dation of China(Grant Nos.12174322,12474200,32271367,and 12204389)111 Project(B16029)Research Grant from Wenzhou Institute.
文摘Spectrin domains,characterized by a distinctive triple helix structure,are crucial in physiological processes,particularly in maintaining membrane shape and crosslinking cytoskeletons.Previous research on the 16th domain of a-spectrin repeats(R16)has yielded conflicting results:bulk experiments showed an unfolding rate approximately two orders of magnitude faster than the zero-force result extrapolated from single-molecule force spectroscopy experiments using atomic force microscopy(AFM).To address this discrepancy,we investigated the folding and unfolding rates of R16 across a broader range of forces using magnetic tweezers(MT).Our findings reveal that AFM results at higher forces cannot be directly extrapolated to the low-force regime due to a nonlinear relationship between force and the logarithm of the unfolding rate.We demonstrated that two-dimensional model,structural-elastic model,and two-pathway model can all effectively explain the experimental data when they capture the core physics of the short unfolding distance at low forces.Our study provides a more comprehensive understanding of the unfolding dynamics of the spectrin domain,resolves previous contradictory experimental results,and highlights the common basis of different theoretical models.
基金support from the National Nat-ural Science Foundation of China(Grant No.12474199)the Fundamental Research Funds for Central Universities of China(Grant No.20720240144),and 111 Project(B16029).
文摘Cell division is a fundamental biological process in which a parent cell divides into two daughter cells.The cell cortex,a thin layer primarily composed of actin filaments and myosin motors beneath the plasma membrane,plays a critical role in ensuring proper cell division.In this study,we apply a hydrodynamic model to describe the actin cortex as an active nematic surface,incorporating orientational order arising from actin filament alignment and anisotropic active stress produced by myosin motors.By analyzing the linearized dynamics,we investigate how shape,flow,and stress regulators evolve over time when the surface deviates slightly from a sphere.Our findings reveal that the active alignment of actin filaments,often overlooked in previous studies,is crucial for successful division.Furthermore,we demonstrate that a cortical chiral flow naturally emerges as a consequence of this active alignment.Overall,our results provide a mechanistic explanation for key phenomena observed during cell division,offering new insights into the role of active stress and filament alignment in cortical dynamics.
基金supported by the Inner Mongolia Natural Science Foundation(2021MS05064)China Northern Rare Earth Group High-Tech Co.,Ltd.(Bayan Obo rare earth resources extraction and application research and key technology development,2022151).
文摘The La_(1.7)Pr_(0.3)Mg_(16)Ni hydrogen storage alloy was prepared by medium-frequency induction melting,and then the composite hydrogen storage alloy powder of La_(1.7)Pr_(0.3)Mg_(16)Ni+x wt.%(x=0,2,4,and 6)graphene was prepared by ball milling for 10 h.The effect of the addition of graphene on the activation and hydrogen de/absorption properties of La_(1.7)Pr_(0.3)Mg_(16)Ni alloy was studied.The result demonstrated that these composite alloys were composed of La_(2)Mg_(17),La_(2)Ni_(3),and Mg_(2)Ni phases.After saturated hydrogen absorption,it was composed of LaH_(3),Mg_(2)NiH_(4),and MgH_(2)phases,while during the dehydrogenation process,it was composed of LaH_(3),Mg,and Mg_(2)Ni phases.The addition of graphene can help get a more homogeneous granule after ball milling and accelerate the first activation of dehydrogenation/hydrogen absorption.The hydrogen release activation energy of the alloys first decreases and then increases as the graphene content increases from x=0 wt.%to x=6 wt.%.The minimum activation energy of the composite hydrogen storage alloy is 51.22 kJ mol^(-1) when x=4 wt.%.
基金support from the the National Natural Science Foundation of China(Grant Nos.12474199(RM)and 12374213(YC))Fundamental Research Funds for Central Universities of China(Grant No.20720240144(RM))111 Project(Grant No.B16029).
文摘Vesicles of lipid bilayer can adopt a variety of shapes due to different coating proteins.The ability of proteins to reshape membrane is typically characterized by inducing spontaneous curvature of the membrane at the coated area.BAR family proteins are known to have a crescent shape and can induce membrane curvature along their concaved body axis but not in the perpendicular direction.We model this type of proteins as a rod-shaped molecule with an orientation and induce normal curvature along its orientation in the tangential plane of the membrane surface.We show how a ring of these proteins reshapes an axisymmetric vesicle when the protein curvature or orientation is varied.A discontinuous shape transformation from a protrusion shape without a neck to a one with a neck is found.Increasing the rigidity of the protein ring is able to smooth out the transition.Furthermore,we show that varying the protein orientation is able to induce an hourglass-shaped neck,which is significantly narrower than the reciprocal of the protein curvature.Our results offer a new angle to rationalize the helical structure formed by many proteins that carry out membrane fission functions.
基金supported by the National Natural Science Foundation of China(Nos.52025132,U24A20205,52303373,21621091,22021001,and 22121001)the China Postdoctoral Science Foundation(No.2024M763174)+2 种基金the 111 Project(Nos.B17027,B16029)the Natural Science Foundation of Fujian Province of China(No.2022J02059)the New Cornerstone Science Foundation through the Xplorer Prize。
文摘Controllable liquid manipulation is of paramount scientific and technological importance in various fields,such as the chemical industry,biomedicine,and agricultural production.Magnetic actuation,characterized by rapid,contactless,and environmentally benign operation,has emerged as a promising approach for precise liquid control.However,conventional magnetic strategies typically govern droplet movement on open surfaces,facing limitations such as restricted liquid volumes,uncertain flow paths,and inevitable evaporation,thereby constraining their broader practical applications.Recently,a variety of magneticdriven strategies have been developed to dynamically regulate liquids within enclosed spaces,especially through physicochemical mechanisms.These approaches provide efficient control over liquid behavior by leveraging magnetically induced chemical changes,structural deformations,and dragging motions,opening new opportunities for flexible and versatile fluid management.This review explores the design and mechanisms of magneto-responsive confined interfaces for the manipulation of nonmagnetic liquids,highlighting key advancements and potential applications including liquid valves,liquid mixing,liquid flow regulation,and liquid pumping.Finally,the existing challenges and future prospects in this field are presented.
基金financial supports from Natural Science Foundation of China(Grant No.61935008,T2325014,62205174 and 62275100)。
文摘Compound eyes(CEs)that feature ultra-compact structures and extraordinary versatility have revealed great potential for cutting-edge applications.However,the optoelectronic integration of CEs with available photodetectors is still challenging because the planar charge-coupled device(CCD)/complementary metal oxide semiconductor(CMOS)detector cannot match the spatially distributed images formed by CE ommatidia.To reach this end,we report here the optoelectronic integration of CEs by manufacturing 3D nonuniform ommatidia for developing an ultra-compact on-chip camera.As a proof-of-concept,we fabricated microscale CEs with uniform and nonuniform ommatidia through femtosecond laser two-photon photopolymerization,and compared their focusing/imaging performance both theoretically and experimentally.By engineering the surface profiles of the ommatidia at different positions of the CE,the images formed by all the ommatidia can be tuned on a plane.In this way,the nonuniform CE can be directly integrated with a commercial CMOS photodetector,forming an ultra-compact CE camera.Additionally,we further combine the CE camera with a microfluidic chip,which can further serve as an on-chip microscopic monitoring system.We anticipate that such an ultra-compact CE camera may find broad applications in microfluidics,robotics,and micro-optics.
基金supported by the National Natural Science Foundation of China(Nos.22275156,52025132,21,621,091,52300138,22021001 and 22121001)the Fundamental Research Funds for the Central Universities of China(No.20720220019)+2 种基金the National Science Foundation of Fujian Province of China(No.2022J02059)the 111 Project(Nos.B17027,B16029)the New Cornerstone Science Foundation through the XPLORER PRIZE。
文摘The development of next-generation electromagnetic wave(EMW)absorbers requires a shift in interface design.By employing hierarchical work function programming,we propose an approach to tune interfacial polarization dynamics.This method utilizes multi-gradient work functions to guide carrier migration and polarization effectively,thereby enhancing energy dissipation under alternating electromagnetic fields.Here,we constructed a 1T/2H-MoS_(2)/PPy/VS_(2) composite absorber with integrated gradient interfaces.The composite achieved a powerful absorption(RLmin)of-58.59 dB at 2.3 mm,and an effective absorption bandwidth(EAB)of 7.44 GHz at 2.5 mm,demonstrating improved broadband absorption.Radar cross-section(RCS)simulations show an EMW loss of-7.2 dB m^(2) at 0°,highlighting its potential for stealth and communication applications.This study introduces hierarchical work function programming as a promising strategy in EMW absorber design,contributing to advancements in material performance and functionality.
