Redox-active porous aromatic frameworks(PAFs)have emerged as hopeful candidates for sodium-ion batteries(SIBs)in view of their porous structures,chemical stability and tunable architectures.Herein,we successfully synt...Redox-active porous aromatic frameworks(PAFs)have emerged as hopeful candidates for sodium-ion batteries(SIBs)in view of their porous structures,chemical stability and tunable architectures.Herein,we successfully synthesized two redox-active PAFs(PAF-305 and PAF-306)with different nitrogen-containing motifs,and demonstrated their application as cathode materials for SIBs.Density functional theory(DFT)calculations reveal that nitrogen-rich PAF-305 exhibits a lower lowest unoccupied molecular orbital(LUMO)energy level(-3.35 eV)and a narrower energy gap(E_(g))(2.40 eV)compared with nitrogen-poor PAF-306.As expected,PAF-305 displays outstanding electrochemical performance,comprising a high reversible capacity of 145.2 mAh g^(-1)at 0.05 A g^(-1)and satisfactory cycling stability with 92% capacity retention over 1000 cycles at 0.2 A g^(-1).Remarkably,PAF-305 maintains robust electrochemical properties across a wide temperature range(-20℃ to 50℃).Through a combination of experimental characterizations and theoretical calculations,the sodium-ion storage mechanism of PAF-305 is elucidated.This study not only provides a promising strategy for exploring other redox-active organic units in the design of novel PAFs,but also expands the potential applications of PAFs in energy storage systems.展开更多
THE Hainan Free Trade Port(FTP)officially launched island-wide special customs operations on December 18,2025.One month in,a reporting team from China International Communications Group(CICG)conducted an exclusive int...THE Hainan Free Trade Port(FTP)officially launched island-wide special customs operations on December 18,2025.One month in,a reporting team from China International Communications Group(CICG)conducted an exclusive interview with Feng Fei,secretary of the Hainan Provincial Committee of the Communist Party of China(CPC)and chairman of the Standing Committee of the Hainan Provincial People’s Congress.展开更多
High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increa...High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum.展开更多
The fast growth of mobile autonomous machines from traditional equipment to unmanned autonomous vehicles has fueled the demand for accurate and reliable localization solutions in diverse application domains.Ultra Wide...The fast growth of mobile autonomous machines from traditional equipment to unmanned autonomous vehicles has fueled the demand for accurate and reliable localization solutions in diverse application domains.Ultra Wide Band(UWB)technology has emerged as a promising candidate for addressing this need,offering high precision,immunity to multipath interference,and robust performance in challenging environments.In this comprehensive survey,we systematically explore UWB-based localization for mobile autonomous machines,spanning from fundamental principles to future trends.To the best of our knowledge,this review paper stands as the pioneer in systematically dissecting the algorithms of UWB-based localization for mobile autonomous machines,covering a spectrum from bottom-ranging schemes to advanced sensor fusion,error mitigation,and optimization techniques.By synthesizing existing knowledge,evaluating current methodologies,and highlighting future trends,this review aims to catalyze progress and innovation in the field,unlocking new opportunities for mobile autonomous machine applications across diverse industries and domains.Thus,it serves as a valuable resource for researchers,practitioners,and stakeholders interested in advancing the state-of-the-art UWB-based localization for mobile autonomous machines.展开更多
In DSP-based SerDes application,it is essential for AFE to implement a pre-ADC equalization to provide a better sig-nal for ADC and DSP.To meet the various equalization requirements of different channel and transmitte...In DSP-based SerDes application,it is essential for AFE to implement a pre-ADC equalization to provide a better sig-nal for ADC and DSP.To meet the various equalization requirements of different channel and transmitter configurations,this paper presents a 112 Gbps DSP-Based PAM4 SerDes receiver with a wide band equalization tuning AFE.The AFE is realized by implementing source degeneration transconductance,feedforward high-pass branch and inductive feedback peaking TIA.The AFE offers a flexible equalization gain tuning of up to 17.5 dB at Nyquist frequency without affecting the DC gain.With the pro-posed AFE,the receiver demonstrates eye opening after digital FIR equalization and achieves 6×10^(-9) BER with a 29.6 dB inser-tion loss channel.展开更多
Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction kine...Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction kinetics.Herein,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as cathode.The unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon illumination.The illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 cycles.Even at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT cathode.This work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.展开更多
Tin(Sn)is considered an effective anode material for stripping and plating due to its promising capacity,isotropic deposition,and relatively negative redox potential of-0.91 V vs.standard hydrogen electrode(SHE).Howev...Tin(Sn)is considered an effective anode material for stripping and plating due to its promising capacity,isotropic deposition,and relatively negative redox potential of-0.91 V vs.standard hydrogen electrode(SHE).However,the challenges of hydrogen evolution corrosion and“dead Sn”formation at the Snalkaline electrolyte interface restrict its reversibility,which poses challenges for flexible devices and in a broad temperature range.In this study,we successfully designed a corrosion-resistant Sn anode(CuPVDF@Sn)featuring a multilevel microchannel structure.The Sn-affinitive Cu mesh with good electronic conductivity lowers the nucleation energy barrier and enhances deposition uniformity,while PVDF improves hydrogen evolution potential.Additionally,the soft Cu mesh and PVDF provide flexibility in design.As a result,the flexible Cu-PVDF@Sn anode achieves a coulombic efficiency(CE)of 92.61% and stable cycling for over 800 h.The flexible Sn-air battery based on this anode exhibits an energy density of 504 Wh kg^(-1),a peak power density of 80 mW cm^(-2),and a cycling stability of 120 h at 5 mA cm^(-2).It also operates effectively within a wide temperature range of -15-60℃,providing strong support for excellent environmental adaptability.The proposed concept in this work might provide a promising alternative for developing stable Sn anodes in flexible Sn-air batteries.展开更多
The high-speed reentry vehicle operates across a broad range of speeds and spatial domains,where optimal aerodynamic shapes for different speeds are contradictory.This makes it challenging for a single-Mach optimizati...The high-speed reentry vehicle operates across a broad range of speeds and spatial domains,where optimal aerodynamic shapes for different speeds are contradictory.This makes it challenging for a single-Mach optimization design to meet aerodynamic performance requirements throughout the vehicle’s flight envelope.Additionally,the strong coupling between aerodynamics and control adds complexity,as fluctuations in aerodynamic parameters due to speed variations complicate control system design.To address these challenges,this study proposes an aerodynamic/control coupling optimization design approach.This method,based on aerodynamic optimization principles,incorporates active control technology,treating aerodynamic layout and control system design as primary components during the conceptual design phase.By integrating the design and evaluation of aerodynamics and control,the approach aims to reduce design iterations and enhance overall flight performance.The comprehensive design of the rotary reentry vehicle,using this optimization strategy,effectively balances performance at supersonic and hypersonic speeds.The results show that the integrated design model meets aerodynamic and control performance requirements over a broader range of Mach numbers,preventing performance degradation due to deviations from the design Mach number,and providing a practical solution for high-speed reentry vehicle design.展开更多
High-voltage dual-ion batteries(DIBs)face significant challenges,including graphite cathode degradation,cathode-electrolyte interphase(CEI)instability,and the thermodynamic instability of conventional carbonate-based ...High-voltage dual-ion batteries(DIBs)face significant challenges,including graphite cathode degradation,cathode-electrolyte interphase(CEI)instability,and the thermodynamic instability of conventional carbonate-based electrolytes,particularly at extreme temperatures.In this study,we develop a stable electrolyte incorporating lithium difluorophosphate(LiDFP)as an additive to enhance the electrochemical performance of DIBs over a wide temperature range.LiDFP preferentially decomposes to form a rapid anion-transporting,mechanically robust CEI layer on graphite,which provides better protection by suppressing graphite's volume expansion,preventing electrolyte oxidative decomposition,and enhancing reaction kinetics.As a result,Li||graphite half cells using LiDFP electrolyte exhibit outstanding rate performance(90.8% capacity retention at 30 C)and excellent cycle stability(82.2% capacity retention after 5000 cycles)at room temperature.Moreover,graphite||graphite full cells with LiDFP electrolyte demonstrate stable discharge capacity across a temperature range of-20 to 40℃,expanding the potential applications of LiDFP.This work establishes a novel strategy for optimizing the interphase through electrolyte design,paving the way for all-climate DIBs with improved performance and stability.展开更多
SnS has emerged as an attractive catalyst for the electrochemical CO_(2)reduction reaction(CO_(2)RR)to formate,while its long-term operational stability is hindered by the self-reduction of Sn^(2+) and sulfur dissolut...SnS has emerged as an attractive catalyst for the electrochemical CO_(2)reduction reaction(CO_(2)RR)to formate,while its long-term operational stability is hindered by the self-reduction of Sn^(2+) and sulfur dissolution.Thus,maintaining high current efficiency across a wide negative potential range to achieve high production rates of formate remains a significant challenge.In this study,we present a heterostructure constructed with SnS and CuS for efficient CO_(2)RR to formate.The SnS-CuS(30)exhibits a remarkable formate Faradaic efficiency(FE_(f))of 93.94%at−1 V vs.reversible hydrogen electrode(RHE)and demonstrates long-term stability for 7.5 h,maintaining high activity(with an average FE_(f)of 85.6%)across a wide negative potential range(from-0.8 to-1.2 V(vs.RHE)).The results reveal that the heterogeneous interface between SnS and CuS mitigates the self-reduction issue of SnS by sacrificing Cu^(2+),highlighting that the true active species is SnS,which effectively resists structural changes during the electrolysis process under the protection of CuS.The synergistic interaction within the CuS and SnS heterostructure,combined with the tendency for electron self-conduction,enables the catalyst to maintain high formate activity and selectivity across a wide potential range.Furthermore,theoretical results further indicate that the incorporation of CuS enhances CO_(2)adsorption and lowers the energy barrier for the formation of formate intermediates.This study inspires the concept of applying protective layers to active species,promoting high selectivity in Sn-based electrocatalysts.展开更多
Searching for compatible electrolytes with Ni_(0.8)C_(00.15)Al_(0.05)LiO_(2-δ)(NCAL)electrodes that exhibit high ionic conductivity at low operational temperatures(<550℃)is crucial for advancing ceramics fuel cel...Searching for compatible electrolytes with Ni_(0.8)C_(00.15)Al_(0.05)LiO_(2-δ)(NCAL)electrodes that exhibit high ionic conductivity at low operational temperatures(<550℃)is crucial for advancing ceramics fuel cells(CFCs)research.In this work,the experimental and theoretical analyses demonstrate that the highly stable single-phase Gd_(3)Ga_(5)O_(12)(GGO)garnet structure,composed of Gd-O octahedrons and Ga-O tetrahedrons,provides more active sites for ion transport,resulting in enhanced peak power density(PPD)and stable open circuit voltage(OCV)at low operational temperatures.The unique internal garnet structure effectively reduces the interfacial impedance of the prepared fuel cell device,provides more active sites at triple-phase boundarie region,and increases the electrochemical stability.As a result,the constructed fuel cell device can deliver a superior peak power density of 770 mW/cm^(2)at 490℃.In addition,X-ray photoelectron spectroscopy,electrochemical impedance spectroscopy,and theoretical calculations further demonstrate electrolyte effectiveness of GGO,enabling stable an OCV even at a low temperature of 370℃under a H_(2)/air environment.This work contributes to a deeper understanding of the underlying mechanisms of a single-layer fuel cell device,which is essential for advancing this promising energy technology,even at a very low temperature of 370℃.展开更多
Background:Whether lactated Ringer's solution is clinically superior to normal saline for routine intravenous administration of fluids is uncertain.Methods:In an open-label,two-period,two-sequence,cross-sectional,...Background:Whether lactated Ringer's solution is clinically superior to normal saline for routine intravenous administration of fluids is uncertain.Methods:In an open-label,two-period,two-sequence,cross-sectional,cluster-randomized,crossover trial,we assigned hospitals in Ontario,Canada,to use either lactated Ringer's solution or normal saline hospital-wide for a period of 12 weeks.展开更多
Mild electrocatalytic nitrate reduction reaction(NO_(3)RR),driven by renewable electricity,is regarded as a desirable strategy for green ammonia synthesis and simultaneous removal of nitrogen-containing environmental ...Mild electrocatalytic nitrate reduction reaction(NO_(3)RR),driven by renewable electricity,is regarded as a desirable strategy for green ammonia synthesis and simultaneous removal of nitrogen-containing environmental pollutants.In view of different supply voltages from renewable energy sources,developing costeffective and efficient electrocatalysts with a wide operating potential window is very meaningful for practical application.However,currently reported catalysts usually need to introduce noble metals to synergistically achieve wide-potential selective ammonia synthesis from nitrate.In this work,we present for the first time a dual-transition-metal electrocatalyst(Fe_(3)C-CuO_(x)@NC,x=0,1)with wide-potential-adaptability for highly selective nitrate reduction to ammonia.Such Fe_(3)C-CuO_(x)@NC with spatially separated CuO_(x)and noblemetal-like Fe_(3)C nanoparticles encapsulated with nitrogen-doped graphitized carbon,exhibits outstanding performance in NO_(3)RR with desirable NH_(3)Faraday efficiency of more than 90%over a wide potential ranging from-0.2 V vs.RHE to-0.6 V vs.RHE,comparable to the reported noble metal catalysts.Different from common tandem catalysis,the wide-potential high ammonia selectivity of Fe_(3)C-CuO_(x)@NC is domina ntly ascribed to the complementary enhancement between CuO_(x)and Fe_(3)C,fully supported by results of experiments and density function theory calculations.CuO_(x)exhibit highly intrinsic nitrate reduction to nitrite to compensate for the slow potential determination step(^(*)NO_(3)→^(*)NO_(3)H)of Fe_(3)C,while Fe_(3)C,besides behaving like noble metals to supply adequate active hydrogens,has both good adsorption and reduction abilities for nitrite species to ammonia.Moreover,Fe_(3)C partially stabilizes active Cu^(0)/Cu^(+)sites,and the unique carbon-layer enca psulation structure effectively prevents the agglomeration and corrosion of metal nanoparticles during the electrocatalysis,thus maintaining good cyclic stability.The Zn-NO_(3)^(-)battery assembled with Fe_(3)C-CuO_(x)@NC can reach a high power density of 5.2 mW cm^(-2)at a potential of 1.0 V vs.Zn,with an NH_(3)Faraday efficiency of 92.4%at a current of 8.0 mA,proving its potential practical application.This advance provides unique insights into complementary catalysis mechanisms on multiple metal sites in NO_(3)RR,and offers a reference for the design of other transition metal electrocatalysts matching with renewable electricity.展开更多
Common anode materials in aqueous alkaline electrolytes,such as cadmium,metal hydrides and zinc,usually suffer from remarkable biotoxicity,high cost,and serious side reactions.To overcome these problems,we develop a c...Common anode materials in aqueous alkaline electrolytes,such as cadmium,metal hydrides and zinc,usually suffer from remarkable biotoxicity,high cost,and serious side reactions.To overcome these problems,we develop a conjugated porous polymer(CPP)in-situ grown on reduced graphene oxide(rGO)and Ketjen black(KB),noted as C_(4)N/rGO and C_(4)N/KB respectively,as the alternative anodes.The results show that C_(4)N/rGO electrode delivers a low redox potential(−0.905 V vs.Ag/AgCl),high specific capacity(268.8 mAh g^(-1) at 0.2 A g^(-1)),ultra-stable and fast sodium ion storage behavior(216 mAh g^(-1) at 20 A g^(-1))in 2 M NaOH electrolyte.The assembled C_(4)N/rGO//Ni(OH)_(2) full battery can cycle stably more than 38,000 cycles.Furthermore,by adding a small amount of antifreeze additive dimethyl sulfoxide(DMSO)to adjust the hydrogen bonding network,the low-temperature performance of the electrolyte(0.1 DMSO/2 M NaOH)is significantly improved while hydrogen evolution is inhibited.Consequently,the C_(4)N/rGO//Ni(OH)_(2) full cell exhibits an energy density of 147.3 Wh Kg^(-1) and ultra-high cycling stability over a wide temperature range from−70 to 45℃.This work provides an ultra-stable high-capacity CPPbased anode and antifreeze electrolyte for aqueous alkaline batteries and will facilitate their practical applications under extreme conditions.展开更多
Silicon-based microring resonator sensors are promising components for lab-on-chip sensing systems.However,developing a microring resonator sensor with both high sensitivity and wide detectable range has remained chal...Silicon-based microring resonator sensors are promising components for lab-on-chip sensing systems.However,developing a microring resonator sensor with both high sensitivity and wide detectable range has remained challenging.Here,we experimentally demonstrate a high-sensitivity and wide-range subwavelength grating microring resonator sensor by leveraging its dispersion properties.展开更多
High-performance flexible pressure sensors have garnered significant attention in fields such as wearable electronics and human-machine interfaces.However,the development of flexible pressure sensors that simultaneous...High-performance flexible pressure sensors have garnered significant attention in fields such as wearable electronics and human-machine interfaces.However,the development of flexible pressure sensors that simultaneously achieve high sensitivity,a wide detection range,and good mechanical stability remains a challenge.In this paper,we propose a flexible piezoresistive pressure sensor based on a Ti_(3)C_(2)Tx(MXene)/polyethylene oxide(PEO)composite nanofiber membrane(CNM).The sensor,utilizing MXene(0.4 wt%)/PEO(5 wt%),exhibits high sensitivity(44.34 kPa^(−1)at 0−50 kPa,12.99 kPa^(−1)at 50−500 kPa)and can reliably monitor physiological signals and other subtle cues.Moreover,the sensor features a wide detection range(0−500 kPa),fast response and recovery time(~150/45 ms),and excellent mechanical stability(over 10000 pressure cycles at maximum load).Through an MXene/PEO sensor array,we demonstrate its applications in human physiological signal monitoring,providing a reliable way to expand the application of MXene-based flexible pressure sensors.展开更多
Organic afterglow materials hold significant potential for applications in information storage,anticounterfeiting,and biological imaging.However,studies on afterglow materials capable of ultra-wide range excitation an...Organic afterglow materials hold significant potential for applications in information storage,anticounterfeiting,and biological imaging.However,studies on afterglow materials capable of ultra-wide range excitation and emission simultaneously are limited.To enhance the practicality of strong emission single-component organic afterglow systems,overcoming the constraints of crystalline or other rigid environments is essential.We have developed solid-state dual-persistent thermally activated delayed fluorescence(TADF)and room temperature phosphorescence(RTP)emissions spanning yellow to red under visible light excitation,utilizing a single-molecule terminal group regulation strategy.The RTP lifetime extends from 4.19 ms to 399.70 ms.These afterglow materials exhibit an ultra-wide absorption range from 200 nm to 800 nm,rendering them capable of being excited by both sunlight simulator and nearinfrared radiation.The upconversion phosphorescence lifetime under 808 nm excitation reaches 13.72μs.The double persistent emission of these compounds is temperature-sensitive.Moreover,following grinding or heat treatment,accompanied by extensive afterglow color conversion due to planarization of excited state conformations and additional efficient kRIsc generation.In addition,the amorphous state post melt annealing facilitates the afterglow transition from yellow to green.Crucially,these compounds also maintain stable ultra-long afterglow emission in aqueous and acid-base environments.Overall,we have successfully developed a series of single-component intelligent luminescent materials that demonstrate significant benefits,including dual TADF and RTP emissions,adjustable afterglow lifetimes,a broad range of excitation and emission wavelengths,multi-modal luminescence not restricted to crystalline states,and robust afterglow performance in challenging environments,setting the stage for the practical deployment of afterglow materials in engineering applications,the upconversion afterglow emission also holds promising potential for applications in the field of biological imaging.展开更多
The phasor data concentrator placement(PDCP)in wide area measurement systems(WAMS)is an optimization problem in the communication network planning for power grid.Instead of using the traditional integer linear program...The phasor data concentrator placement(PDCP)in wide area measurement systems(WAMS)is an optimization problem in the communication network planning for power grid.Instead of using the traditional integer linear programming(ILP)based modeling and solution schemes that ignore the graph-related features of WAMS,in this work,the PDCP problem is solved through a heuristic graphbased two-phase procedure(TPP):topology partitioning,and phasor data concentrator(PDC)provisioning.Based on the existing minimum k-section algorithms in graph theory,the k-base topology partitioning algorithm is proposed.To improve the performance,the“center-node-last”pre-partitioning algorithm is proposed to give an initial partition before the k-base partitioning algorithm is applied.Then,the PDC provisioning algorithm is proposed to locate PDCs into the decomposed sub-graphs.The proposed TPP was evaluated on five different IEEE benchmark test power systems and the achieved overall communication performance compared to the ILP based schemes show the validity and efficiency of the proposed method.展开更多
Experimental research into the hydraulic conductivity curve (HCC) of unsaturated soil is limited due to the inherent challenge associated with labor, cost, and time. Typically, the HCC is estimated using the soil wate...Experimental research into the hydraulic conductivity curve (HCC) of unsaturated soil is limited due to the inherent challenge associated with labor, cost, and time. Typically, the HCC is estimated using the soil water characteristic curve (SWCC) based models and saturated hydraulic conductivity (SHC). However, the efficiency of the SWCC-based model is rarely assessed, and the influence of soil density and pore structure on HCC remains incomplete due to limited experimental data. To address this gap, this study employs an innovative filter-paper-based column method, which can measure the HCC over a wide suction range (e.g. 0−105 kPa), to capture the HCCs of both intact and compacted specimens with varying dry densities. The efficiency of two typical SWCC-based models is assessed using the measured data. Meanwhile, the mercury intrusion porosity (MIP) technique is employed to obtain the pore characteristic (i.e. pore size distribution (PSD)) and a method of predicting the HCC using the PSD data is proposed, emphasizing the dominant role of the pore structure in shaping the HCC. The results reveal that the dry density's influence on the HCC is primarily observed within the low suction range, corresponding to variations in the dominant and large pores. In the high suction range, the HCCs align along a linear trajectory when plotted in a log-log format. A notable finding is the overestimation of the HCC obtained from the SWCC-based models using the measured SHC. When the SHC is regarded as a fitting parameter, good agreement is achieved. The adjusted SHC value is typically 0-1 order of magnitude lower than the measured value, and this discrepancy diminishes as dry density increases. On the other hand, the proposed PSD-based model performs well with the measured SHC data. Caution is exercised when using the SHC to estimate the HCC for modeling water movement in partially saturated soil.展开更多
基金supported by the Science&Technology Department of Jilin Province(20230508057RC)。
文摘Redox-active porous aromatic frameworks(PAFs)have emerged as hopeful candidates for sodium-ion batteries(SIBs)in view of their porous structures,chemical stability and tunable architectures.Herein,we successfully synthesized two redox-active PAFs(PAF-305 and PAF-306)with different nitrogen-containing motifs,and demonstrated their application as cathode materials for SIBs.Density functional theory(DFT)calculations reveal that nitrogen-rich PAF-305 exhibits a lower lowest unoccupied molecular orbital(LUMO)energy level(-3.35 eV)and a narrower energy gap(E_(g))(2.40 eV)compared with nitrogen-poor PAF-306.As expected,PAF-305 displays outstanding electrochemical performance,comprising a high reversible capacity of 145.2 mAh g^(-1)at 0.05 A g^(-1)and satisfactory cycling stability with 92% capacity retention over 1000 cycles at 0.2 A g^(-1).Remarkably,PAF-305 maintains robust electrochemical properties across a wide temperature range(-20℃ to 50℃).Through a combination of experimental characterizations and theoretical calculations,the sodium-ion storage mechanism of PAF-305 is elucidated.This study not only provides a promising strategy for exploring other redox-active organic units in the design of novel PAFs,but also expands the potential applications of PAFs in energy storage systems.
文摘THE Hainan Free Trade Port(FTP)officially launched island-wide special customs operations on December 18,2025.One month in,a reporting team from China International Communications Group(CICG)conducted an exclusive interview with Feng Fei,secretary of the Hainan Provincial Committee of the Communist Party of China(CPC)and chairman of the Standing Committee of the Hainan Provincial People’s Congress.
基金supported by the National Nature Science Foundation of China(Nos.22305066 and 52372041).
文摘High-temperature microwave absorbing materials(MAMs)and structures are increasingly appealing due to their critical role in stealth applications under harsh environments.However,the impedance mismatch caused by increased conduction loss often leads to a significant decline in electromagnetic wave absorp-tion(EMWA)performance at elevated temperatures,which severely restricts their practical application.In this study,we propose a novel approach for efficient electromagnetic wave absorption across a wide temperature range using reduced graphene oxide(RGO)/epoxy resin(EP)metacomposites that integrate both electromagnetic parameters and metamaterial design concepts.Due to the discrete distribution of the units,electromagnetic waves can more easily penetrate the interior of materials,thereby exhibiting stable microwave absorption(MA)performance and impedance-matching characteristics suitable across a wide temperature range.Consequently,exceptional MA properties can be achieved within the tem-perature range from 298 to 473 K.Furthermore,by carefully controlling the structural parameters in RGO metacomposites,both the resonant frequency and effective absorption bandwidth(EAB)can be optimized based on precise manipulation of equivalent electromagnetic parameters.This study not only provides an effective approach for the rational design of MA performance but also offers novel insights into achieving super metamaterials with outstanding performance across a wide temperature spectrum.
文摘The fast growth of mobile autonomous machines from traditional equipment to unmanned autonomous vehicles has fueled the demand for accurate and reliable localization solutions in diverse application domains.Ultra Wide Band(UWB)technology has emerged as a promising candidate for addressing this need,offering high precision,immunity to multipath interference,and robust performance in challenging environments.In this comprehensive survey,we systematically explore UWB-based localization for mobile autonomous machines,spanning from fundamental principles to future trends.To the best of our knowledge,this review paper stands as the pioneer in systematically dissecting the algorithms of UWB-based localization for mobile autonomous machines,covering a spectrum from bottom-ranging schemes to advanced sensor fusion,error mitigation,and optimization techniques.By synthesizing existing knowledge,evaluating current methodologies,and highlighting future trends,this review aims to catalyze progress and innovation in the field,unlocking new opportunities for mobile autonomous machine applications across diverse industries and domains.Thus,it serves as a valuable resource for researchers,practitioners,and stakeholders interested in advancing the state-of-the-art UWB-based localization for mobile autonomous machines.
基金supported by National Key R&D Program of China No.2022YFB2803401.
文摘In DSP-based SerDes application,it is essential for AFE to implement a pre-ADC equalization to provide a better sig-nal for ADC and DSP.To meet the various equalization requirements of different channel and transmitter configurations,this paper presents a 112 Gbps DSP-Based PAM4 SerDes receiver with a wide band equalization tuning AFE.The AFE is realized by implementing source degeneration transconductance,feedforward high-pass branch and inductive feedback peaking TIA.The AFE offers a flexible equalization gain tuning of up to 17.5 dB at Nyquist frequency without affecting the DC gain.With the pro-posed AFE,the receiver demonstrates eye opening after digital FIR equalization and achieves 6×10^(-9) BER with a 29.6 dB inser-tion loss channel.
基金supported by the National Natural Science Foundation of China(52072173)the International Science and Technology Cooperation Program of Jiangsu Province(SBZ2022000084).
文摘Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction kinetics.Herein,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as cathode.The unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon illumination.The illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 cycles.Even at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT cathode.This work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.
基金funded by the National Nature Science Foundation of China(62264006)the Special Basic Cooperative Research Programs of Yunnan Provincial Undergraduate Universities’Association(202101BA070001-034)+1 种基金the“Thousand Talents Program”of Yunnan Province for Young Talents,XingDian Talent Support Program for Young TalentsFrontier Research Team of Kunming University 2023。
文摘Tin(Sn)is considered an effective anode material for stripping and plating due to its promising capacity,isotropic deposition,and relatively negative redox potential of-0.91 V vs.standard hydrogen electrode(SHE).However,the challenges of hydrogen evolution corrosion and“dead Sn”formation at the Snalkaline electrolyte interface restrict its reversibility,which poses challenges for flexible devices and in a broad temperature range.In this study,we successfully designed a corrosion-resistant Sn anode(CuPVDF@Sn)featuring a multilevel microchannel structure.The Sn-affinitive Cu mesh with good electronic conductivity lowers the nucleation energy barrier and enhances deposition uniformity,while PVDF improves hydrogen evolution potential.Additionally,the soft Cu mesh and PVDF provide flexibility in design.As a result,the flexible Cu-PVDF@Sn anode achieves a coulombic efficiency(CE)of 92.61% and stable cycling for over 800 h.The flexible Sn-air battery based on this anode exhibits an energy density of 504 Wh kg^(-1),a peak power density of 80 mW cm^(-2),and a cycling stability of 120 h at 5 mA cm^(-2).It also operates effectively within a wide temperature range of -15-60℃,providing strong support for excellent environmental adaptability.The proposed concept in this work might provide a promising alternative for developing stable Sn anodes in flexible Sn-air batteries.
基金supported by the National Natural Science Foundation of China(Grant Nos.52192633,92371201,11872293,and 92152301)the Natural Science Foundation of Shaanxi Province(Grant No.2022JC-03).
文摘The high-speed reentry vehicle operates across a broad range of speeds and spatial domains,where optimal aerodynamic shapes for different speeds are contradictory.This makes it challenging for a single-Mach optimization design to meet aerodynamic performance requirements throughout the vehicle’s flight envelope.Additionally,the strong coupling between aerodynamics and control adds complexity,as fluctuations in aerodynamic parameters due to speed variations complicate control system design.To address these challenges,this study proposes an aerodynamic/control coupling optimization design approach.This method,based on aerodynamic optimization principles,incorporates active control technology,treating aerodynamic layout and control system design as primary components during the conceptual design phase.By integrating the design and evaluation of aerodynamics and control,the approach aims to reduce design iterations and enhance overall flight performance.The comprehensive design of the rotary reentry vehicle,using this optimization strategy,effectively balances performance at supersonic and hypersonic speeds.The results show that the integrated design model meets aerodynamic and control performance requirements over a broader range of Mach numbers,preventing performance degradation due to deviations from the design Mach number,and providing a practical solution for high-speed reentry vehicle design.
基金the financial support received from the National Natural Science Foundation of China(22378426,22138013)the Natural Science Foundation of Shandong Province(ZR2022MB088)the Taishan Scholar Project(ts201712020)。
文摘High-voltage dual-ion batteries(DIBs)face significant challenges,including graphite cathode degradation,cathode-electrolyte interphase(CEI)instability,and the thermodynamic instability of conventional carbonate-based electrolytes,particularly at extreme temperatures.In this study,we develop a stable electrolyte incorporating lithium difluorophosphate(LiDFP)as an additive to enhance the electrochemical performance of DIBs over a wide temperature range.LiDFP preferentially decomposes to form a rapid anion-transporting,mechanically robust CEI layer on graphite,which provides better protection by suppressing graphite's volume expansion,preventing electrolyte oxidative decomposition,and enhancing reaction kinetics.As a result,Li||graphite half cells using LiDFP electrolyte exhibit outstanding rate performance(90.8% capacity retention at 30 C)and excellent cycle stability(82.2% capacity retention after 5000 cycles)at room temperature.Moreover,graphite||graphite full cells with LiDFP electrolyte demonstrate stable discharge capacity across a temperature range of-20 to 40℃,expanding the potential applications of LiDFP.This work establishes a novel strategy for optimizing the interphase through electrolyte design,paving the way for all-climate DIBs with improved performance and stability.
基金supported by the National Key Research and Development Program of China(No.2018YFB1501405)the National Natural Science Foundation of China(No.52476185).
文摘SnS has emerged as an attractive catalyst for the electrochemical CO_(2)reduction reaction(CO_(2)RR)to formate,while its long-term operational stability is hindered by the self-reduction of Sn^(2+) and sulfur dissolution.Thus,maintaining high current efficiency across a wide negative potential range to achieve high production rates of formate remains a significant challenge.In this study,we present a heterostructure constructed with SnS and CuS for efficient CO_(2)RR to formate.The SnS-CuS(30)exhibits a remarkable formate Faradaic efficiency(FE_(f))of 93.94%at−1 V vs.reversible hydrogen electrode(RHE)and demonstrates long-term stability for 7.5 h,maintaining high activity(with an average FE_(f)of 85.6%)across a wide negative potential range(from-0.8 to-1.2 V(vs.RHE)).The results reveal that the heterogeneous interface between SnS and CuS mitigates the self-reduction issue of SnS by sacrificing Cu^(2+),highlighting that the true active species is SnS,which effectively resists structural changes during the electrolysis process under the protection of CuS.The synergistic interaction within the CuS and SnS heterostructure,combined with the tendency for electron self-conduction,enables the catalyst to maintain high formate activity and selectivity across a wide potential range.Furthermore,theoretical results further indicate that the incorporation of CuS enhances CO_(2)adsorption and lowers the energy barrier for the formation of formate intermediates.This study inspires the concept of applying protective layers to active species,promoting high selectivity in Sn-based electrocatalysts.
基金supported by the Jiangsu Fundamental Research Program(JSSCRC2021491)Ongoing Research Funding Program(ORF-2025-391)。
文摘Searching for compatible electrolytes with Ni_(0.8)C_(00.15)Al_(0.05)LiO_(2-δ)(NCAL)electrodes that exhibit high ionic conductivity at low operational temperatures(<550℃)is crucial for advancing ceramics fuel cells(CFCs)research.In this work,the experimental and theoretical analyses demonstrate that the highly stable single-phase Gd_(3)Ga_(5)O_(12)(GGO)garnet structure,composed of Gd-O octahedrons and Ga-O tetrahedrons,provides more active sites for ion transport,resulting in enhanced peak power density(PPD)and stable open circuit voltage(OCV)at low operational temperatures.The unique internal garnet structure effectively reduces the interfacial impedance of the prepared fuel cell device,provides more active sites at triple-phase boundarie region,and increases the electrochemical stability.As a result,the constructed fuel cell device can deliver a superior peak power density of 770 mW/cm^(2)at 490℃.In addition,X-ray photoelectron spectroscopy,electrochemical impedance spectroscopy,and theoretical calculations further demonstrate electrolyte effectiveness of GGO,enabling stable an OCV even at a low temperature of 370℃under a H_(2)/air environment.This work contributes to a deeper understanding of the underlying mechanisms of a single-layer fuel cell device,which is essential for advancing this promising energy technology,even at a very low temperature of 370℃.
文摘Background:Whether lactated Ringer's solution is clinically superior to normal saline for routine intravenous administration of fluids is uncertain.Methods:In an open-label,two-period,two-sequence,cross-sectional,cluster-randomized,crossover trial,we assigned hospitals in Ontario,Canada,to use either lactated Ringer's solution or normal saline hospital-wide for a period of 12 weeks.
基金financial support from the National Natural Science Foundation of China(NSFC 22172082)the Fundamental Research Funds for the Central Universities。
文摘Mild electrocatalytic nitrate reduction reaction(NO_(3)RR),driven by renewable electricity,is regarded as a desirable strategy for green ammonia synthesis and simultaneous removal of nitrogen-containing environmental pollutants.In view of different supply voltages from renewable energy sources,developing costeffective and efficient electrocatalysts with a wide operating potential window is very meaningful for practical application.However,currently reported catalysts usually need to introduce noble metals to synergistically achieve wide-potential selective ammonia synthesis from nitrate.In this work,we present for the first time a dual-transition-metal electrocatalyst(Fe_(3)C-CuO_(x)@NC,x=0,1)with wide-potential-adaptability for highly selective nitrate reduction to ammonia.Such Fe_(3)C-CuO_(x)@NC with spatially separated CuO_(x)and noblemetal-like Fe_(3)C nanoparticles encapsulated with nitrogen-doped graphitized carbon,exhibits outstanding performance in NO_(3)RR with desirable NH_(3)Faraday efficiency of more than 90%over a wide potential ranging from-0.2 V vs.RHE to-0.6 V vs.RHE,comparable to the reported noble metal catalysts.Different from common tandem catalysis,the wide-potential high ammonia selectivity of Fe_(3)C-CuO_(x)@NC is domina ntly ascribed to the complementary enhancement between CuO_(x)and Fe_(3)C,fully supported by results of experiments and density function theory calculations.CuO_(x)exhibit highly intrinsic nitrate reduction to nitrite to compensate for the slow potential determination step(^(*)NO_(3)→^(*)NO_(3)H)of Fe_(3)C,while Fe_(3)C,besides behaving like noble metals to supply adequate active hydrogens,has both good adsorption and reduction abilities for nitrite species to ammonia.Moreover,Fe_(3)C partially stabilizes active Cu^(0)/Cu^(+)sites,and the unique carbon-layer enca psulation structure effectively prevents the agglomeration and corrosion of metal nanoparticles during the electrocatalysis,thus maintaining good cyclic stability.The Zn-NO_(3)^(-)battery assembled with Fe_(3)C-CuO_(x)@NC can reach a high power density of 5.2 mW cm^(-2)at a potential of 1.0 V vs.Zn,with an NH_(3)Faraday efficiency of 92.4%at a current of 8.0 mA,proving its potential practical application.This advance provides unique insights into complementary catalysis mechanisms on multiple metal sites in NO_(3)RR,and offers a reference for the design of other transition metal electrocatalysts matching with renewable electricity.
基金financial support by the National Natural Science Foundation of China(22371010,21771017 and 51702009)the“Hundred Talents Program”of the Chinese Academy of Science,Fundamental Research Funds for the Central Universities,Shenzhen Science and Technology Program(JCYJ20210324115412035 JCYJ2021-0324123202008,JCYJ20210324122803009 and ZDSYS20210813095534001)Guangdong Basic and Applied Basic Research Foundation(2021A1515110880).
文摘Common anode materials in aqueous alkaline electrolytes,such as cadmium,metal hydrides and zinc,usually suffer from remarkable biotoxicity,high cost,and serious side reactions.To overcome these problems,we develop a conjugated porous polymer(CPP)in-situ grown on reduced graphene oxide(rGO)and Ketjen black(KB),noted as C_(4)N/rGO and C_(4)N/KB respectively,as the alternative anodes.The results show that C_(4)N/rGO electrode delivers a low redox potential(−0.905 V vs.Ag/AgCl),high specific capacity(268.8 mAh g^(-1) at 0.2 A g^(-1)),ultra-stable and fast sodium ion storage behavior(216 mAh g^(-1) at 20 A g^(-1))in 2 M NaOH electrolyte.The assembled C_(4)N/rGO//Ni(OH)_(2) full battery can cycle stably more than 38,000 cycles.Furthermore,by adding a small amount of antifreeze additive dimethyl sulfoxide(DMSO)to adjust the hydrogen bonding network,the low-temperature performance of the electrolyte(0.1 DMSO/2 M NaOH)is significantly improved while hydrogen evolution is inhibited.Consequently,the C_(4)N/rGO//Ni(OH)_(2) full cell exhibits an energy density of 147.3 Wh Kg^(-1) and ultra-high cycling stability over a wide temperature range from−70 to 45℃.This work provides an ultra-stable high-capacity CPPbased anode and antifreeze electrolyte for aqueous alkaline batteries and will facilitate their practical applications under extreme conditions.
基金National Key Research and Development Program of China(2022YFB2803600)National Natural Science Foundation of China(61905022,62175080)+3 种基金Department of Science and Technology of Jilin Province(20240101338JC)Songshan Lake Materials Laboratory(2023SLABFK11)Science and Technology Planning Project of Shenzhen Municipality(CJGJZD20220517141202005)Hubei Provincial Program for Outstanding Young Talents。
文摘Silicon-based microring resonator sensors are promising components for lab-on-chip sensing systems.However,developing a microring resonator sensor with both high sensitivity and wide detectable range has remained challenging.Here,we experimentally demonstrate a high-sensitivity and wide-range subwavelength grating microring resonator sensor by leveraging its dispersion properties.
基金support from Beijing Natural Science Foundation−Xiaomi Innovation Joint Fund(Grant No.L233009)the National Natural Science Foundation of China(NSFC Grant Nos.62422409,62174152 and 62374159)from the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2020115).
文摘High-performance flexible pressure sensors have garnered significant attention in fields such as wearable electronics and human-machine interfaces.However,the development of flexible pressure sensors that simultaneously achieve high sensitivity,a wide detection range,and good mechanical stability remains a challenge.In this paper,we propose a flexible piezoresistive pressure sensor based on a Ti_(3)C_(2)Tx(MXene)/polyethylene oxide(PEO)composite nanofiber membrane(CNM).The sensor,utilizing MXene(0.4 wt%)/PEO(5 wt%),exhibits high sensitivity(44.34 kPa^(−1)at 0−50 kPa,12.99 kPa^(−1)at 50−500 kPa)and can reliably monitor physiological signals and other subtle cues.Moreover,the sensor features a wide detection range(0−500 kPa),fast response and recovery time(~150/45 ms),and excellent mechanical stability(over 10000 pressure cycles at maximum load).Through an MXene/PEO sensor array,we demonstrate its applications in human physiological signal monitoring,providing a reliable way to expand the application of MXene-based flexible pressure sensors.
基金financially supported by the National Natural Science Foundation of China(No.21871122)。
文摘Organic afterglow materials hold significant potential for applications in information storage,anticounterfeiting,and biological imaging.However,studies on afterglow materials capable of ultra-wide range excitation and emission simultaneously are limited.To enhance the practicality of strong emission single-component organic afterglow systems,overcoming the constraints of crystalline or other rigid environments is essential.We have developed solid-state dual-persistent thermally activated delayed fluorescence(TADF)and room temperature phosphorescence(RTP)emissions spanning yellow to red under visible light excitation,utilizing a single-molecule terminal group regulation strategy.The RTP lifetime extends from 4.19 ms to 399.70 ms.These afterglow materials exhibit an ultra-wide absorption range from 200 nm to 800 nm,rendering them capable of being excited by both sunlight simulator and nearinfrared radiation.The upconversion phosphorescence lifetime under 808 nm excitation reaches 13.72μs.The double persistent emission of these compounds is temperature-sensitive.Moreover,following grinding or heat treatment,accompanied by extensive afterglow color conversion due to planarization of excited state conformations and additional efficient kRIsc generation.In addition,the amorphous state post melt annealing facilitates the afterglow transition from yellow to green.Crucially,these compounds also maintain stable ultra-long afterglow emission in aqueous and acid-base environments.Overall,we have successfully developed a series of single-component intelligent luminescent materials that demonstrate significant benefits,including dual TADF and RTP emissions,adjustable afterglow lifetimes,a broad range of excitation and emission wavelengths,multi-modal luminescence not restricted to crystalline states,and robust afterglow performance in challenging environments,setting the stage for the practical deployment of afterglow materials in engineering applications,the upconversion afterglow emission also holds promising potential for applications in the field of biological imaging.
基金supported by the National Key Research and Development Program of China(2023YFB 2906403).
文摘The phasor data concentrator placement(PDCP)in wide area measurement systems(WAMS)is an optimization problem in the communication network planning for power grid.Instead of using the traditional integer linear programming(ILP)based modeling and solution schemes that ignore the graph-related features of WAMS,in this work,the PDCP problem is solved through a heuristic graphbased two-phase procedure(TPP):topology partitioning,and phasor data concentrator(PDC)provisioning.Based on the existing minimum k-section algorithms in graph theory,the k-base topology partitioning algorithm is proposed.To improve the performance,the“center-node-last”pre-partitioning algorithm is proposed to give an initial partition before the k-base partitioning algorithm is applied.Then,the PDC provisioning algorithm is proposed to locate PDCs into the decomposed sub-graphs.The proposed TPP was evaluated on five different IEEE benchmark test power systems and the achieved overall communication performance compared to the ILP based schemes show the validity and efficiency of the proposed method.
基金supported by the National Natural Science Foundation of China(Grant No.41825018)Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA23090402)the National Natural Science Foundation of China(Grant No.42141009).
文摘Experimental research into the hydraulic conductivity curve (HCC) of unsaturated soil is limited due to the inherent challenge associated with labor, cost, and time. Typically, the HCC is estimated using the soil water characteristic curve (SWCC) based models and saturated hydraulic conductivity (SHC). However, the efficiency of the SWCC-based model is rarely assessed, and the influence of soil density and pore structure on HCC remains incomplete due to limited experimental data. To address this gap, this study employs an innovative filter-paper-based column method, which can measure the HCC over a wide suction range (e.g. 0−105 kPa), to capture the HCCs of both intact and compacted specimens with varying dry densities. The efficiency of two typical SWCC-based models is assessed using the measured data. Meanwhile, the mercury intrusion porosity (MIP) technique is employed to obtain the pore characteristic (i.e. pore size distribution (PSD)) and a method of predicting the HCC using the PSD data is proposed, emphasizing the dominant role of the pore structure in shaping the HCC. The results reveal that the dry density's influence on the HCC is primarily observed within the low suction range, corresponding to variations in the dominant and large pores. In the high suction range, the HCCs align along a linear trajectory when plotted in a log-log format. A notable finding is the overestimation of the HCC obtained from the SWCC-based models using the measured SHC. When the SHC is regarded as a fitting parameter, good agreement is achieved. The adjusted SHC value is typically 0-1 order of magnitude lower than the measured value, and this discrepancy diminishes as dry density increases. On the other hand, the proposed PSD-based model performs well with the measured SHC data. Caution is exercised when using the SHC to estimate the HCC for modeling water movement in partially saturated soil.
