CO_(2) hydrogenation using protonic ceramic electrolysis cells(PCECs)to produce fuel gases such as CH_(4)and CO has been considered as a promising technology for effective CO_(2) utilization.However,the long-term stab...CO_(2) hydrogenation using protonic ceramic electrolysis cells(PCECs)to produce fuel gases such as CH_(4)and CO has been considered as a promising technology for effective CO_(2) utilization.However,the long-term stability of conventional PCECs based on Y and Yb doped BaZrO_(3)-BaCeO_(3)(BCZYYb)proton conductors is severely limited by their susceptibility to carbonate formation under high concentration CO_(2) .In this work,a new type PCEC based on CO_(2) -tolerant La_(5.6)WO_(11.4-δ)(LWO)material is firstly constructed.A three-layer porous-dense-porous LWO ceramic scaffold is fabricated via a pressing,dip-coating and cosintering process,followed by Ni and La_(0.6)Sr_(0.4)CoO_(3-δ)(LSC)catalyst impregnation to ensure the chemical compatibility among materials and form an efficient PCEC-based CO_(2) hydrogenation reactor.Benefits from the synergistic catalysis of nano nickel and LWO,the reactor gets a CH_(4)selectivity of over 50%at 600℃under 20%CO_(2) concentration,and it operates stably for over 320 h at 600–650℃under high CO_(2) concentrations of 50–80%,showing no degradation in CO_(2) conversion rate or CH_(4)selectivity.Postmortem analysis demonstrates that the CO_(2) absorption characteristics of LWO and the morphological uniformity of nano nickel lead to stable CO_(2) methanation.This study provides a viable strategy for designing highly stable PCEC-based CO_(2) hydrogenation reactors.展开更多
In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still face...In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still faced with defects such as low intrinsic ionic conductivity,a narrow electrochemical window,and poor thermal stability.A crosslinking and fluorination molecular design strategy toward PDOL is proposed to tackle the issues above.The amorphous crosslinked structure effectively improves ionic conductivity by inhibiting long-chain crystallization.Especially,the antioxidant–CF_(3)groups,stable crosslinked structure,and reduced terminal hydroxyl groups significantly enhance the electrochemical oxidation stability with a superb high-voltage window of 4.7 V.In addition,the designed electrolyte also exhibits obviously improved thermal stability with no deformation at 120°C for 5 min.Furthermore,the semi-solid NCM811||Li batteries exhibit a favourable capacity retention of 88.8%after 150 cycles at 0.5 C.Even assembled with NCM622 cathode working at 4.5 V,the semi-solid batteries can still show a satisfactory capacity retention of 85.3%after 100 cycles at 0.5 C.Also,a 0.1 Ah NCM811||Li pouch cell with active materials loading of 9 mg/cm2 demonstrates satisfactory cycling stability and working ability,which shows promising practical application prospects.展开更多
Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded...Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded organic frameworks(HOFs)have promising application potential for embedding enzymes.In fact,no metal involvement is required,and HOFs exhibit superior biocompatibility,and free access to substrates in mesoporous channels.Herein,a facile in situ growth approach was proposed for the self-assembly of alcohol dehydrogenase encapsulated in HOF.The micron-scale bio-catalytic composite was rapidly synthesized under mild conditions(aqueous phase and ambient temperature)with a controllable embedding rate.The high crystallinity and periodic arrangement channels of HOF were preserved at a high enzyme encapsulation efficiency of 59%.This bio-composite improved the tolerance of the enzyme to the acid-base environment and retained 81%of its initial activity after five cycles of batch hydrogenation involving NADH coenzyme.Based on this controllably synthesized bio-catalytic material and a common lipase,we further developed a two-stage cascade microchemical system and achieved the continuous production of chiral hydroxybutyric acid(R-3-HBA).展开更多
As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple ...As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple output(MIMO)technique to improve its capacity and coverage.Thus,testing new functions of the 5G MIMO system accurately and ef-ficiently,including beamforming(beam-tracking with movement)and multiple-user(MU)multiplexing,is a challenging task.This paper tries to construct a lab-oratorial hardware and conduct equipment-controlled field testing.Firstly,the testing scheme is presented,which is composed of the framework,the channel models and the validation methods.Then,the channel model principles are explained in detail due to its di-rect influence on the testing accuracy.Specifically,we utilize the spatial consistency and the multi-link cor-relation properties to emulate the high-speed dynamic time-varying(HDT)and the multiple-cell(MC)-MU-MIMO channels.Finally,the above testing scheme is verified in a Shanghai 5G field experiment with the practical commercial equipment and the channel em-ulator.The results show that the 5G new functions are tested accurately and efficiently by switching the channel emulation configurations.展开更多
With the rapid growth of the low-altitude economy,the demand for typical low-altitude ap-plications has accelerated the advancement of inte-grated sensing and communications(ISAC)networks.This paper begins by analyzin...With the rapid growth of the low-altitude economy,the demand for typical low-altitude ap-plications has accelerated the advancement of inte-grated sensing and communications(ISAC)networks.This paper begins by analyzing representative ap-plication scenarios to clarify the core requirements of the low-altitude economy for modern ISAC net-works.By investigating the distinctive characteris-tics of ISAC networks in low-altitude environments,it presents a comprehensive analysis of key challenges and identifies four major issues:challenges in pre-cise target detection,interference management,in-consistent sensing and communication coverage,and the complexity of air-ground coordination and han-dover.Based on fundamental theories and principles,the paper proposes corresponding solutions,encom-passing advanced technologies for precise target de-tection and recognition,high-reliability networked de-tection,robust interference management,and seamless air-ground collaboration.These solutions aim to es-tablish a solid foundation for the future development of intelligent low-altitude networks and ensure effec-tive support for emerging applications.展开更多
Extremely large-scale multiple-input multiple-output(XL-MIMO)is regarded as a promis-ing technology for next-generation communication systems.However,this will expand the near-field(NF)range,rendering more users more ...Extremely large-scale multiple-input multiple-output(XL-MIMO)is regarded as a promis-ing technology for next-generation communication systems.However,this will expand the near-field(NF)range,rendering more users more likely to be located in the NF region.In this paper,we aim to answer two questions:What are the new characteristics of the NF channel?Is it necessary to develop new transciver techniques to maintain system performance within the NF region?To this end,we first review current NF channel models and analyze the differences between the existing 3GPP TR 38.901 channel model and the NF channel model,including the spherical wavefront and spatially non-stationarity.Then,we provide ex-amples on how these differences affect the XL-MIMO system performance in terms of beamforming gain and achievable rate.Simulation results demonstrate that,when using far-field(FF)technique under the NF channel,the maximum normalized beam gain loss is less than 3 dB for most users in the NF region de-fined by Rayleigh distance.Moreover,the achievable rate loss of beam training is less than 3%compared to that realized by NF technique.Finally,we demonstrate the necessity of employing NF transceiver techniques based on simulation results.展开更多
Solid-state polymer sodium batteries(SPSBs)are promising candidates for achieving higher energy density and safe energy storage.However,interface issues between oxide cathode and solid-state polymer electrolyte are a ...Solid-state polymer sodium batteries(SPSBs)are promising candidates for achieving higher energy density and safe energy storage.However,interface issues between oxide cathode and solid-state polymer electrolyte are a great challenge for their commercial application.In contrast,soft sulfur-based materials feature better interface contact and chemical compatibility.Herein,an interfacial compatible polysulfide Ti_(4)P_(8)S_(29) with robust Ti-S bonding and a highly active P-S unit is tailored as a high-performance cathode for SPSBs.The Ti_(4)P_(8)S_(29) cathode possesses a three-dimensional channel structure for offering ample Na+diffusion pathways.The assembled poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)-based SPSBs deliver a discharge capacity of 136 mAh·g^(-1)at 0.5C after 200 cycles.Furthermore,a discharge capacity of 88 mAh·g^(-1)is retained after 600 cycles at a high rate of 2C,surpassing many cathode materials in SPSBs.A dual-site redox of Ti^(4+)/Ti^(3+)and S^(-)/S^(2-)is verified by X-ray photoelectron spectroscopy(XPS)and cyclic voltammetry(CV)tests.Interestingly,a refined locally-ordered amorphous structure is unveiled by in situ and ex situ characterizations.The as-formed electrode structure with lots of open channels and isotropic properties are more beneficial for ion diffusion on the interface of electrode and solid-state polymer electrolytes(SPEs),leading to faster Na+diffusion kinetics.This work proposes a strategy of modulating open-channel to boost conversion kinetics in polysulfide cathode and opens a new pathway for designing high-performance SPSBs.展开更多
With the widespread adoption of lithium-ion batteries(LIBs),safety concerns associated with flammable organic elec-trolytes have become increasingly critical.Solid-state lithium batteries(SSLBs),with enhanced safety a...With the widespread adoption of lithium-ion batteries(LIBs),safety concerns associated with flammable organic elec-trolytes have become increasingly critical.Solid-state lithium batteries(SSLBs),with enhanced safety and higher energy density potential,are regarded as a promising next-generation energy storage technology.However,the practical appli-cation of solid-state electrolytes(SSEs)remains hindered by several challenges,including low Li^(+)ion conductivity,poor interfacial compatibility with electrodes,unfavorable mechanical properties and difficulties in scalable manufacturing.This review systematically examines recent progress in SSEs,including inorganic types(oxides,sulfides,halides),organic types(polymers,plastic crystals,poly(ionic liquids)(PILs)),and the emerging class of soft solid-state electrolytes(S3Es),especially those based on“rigid-flexible synergy”composites and“Li+-desolvation”mechanism using porous frameworks.Critical assessment reveals that single-component SSEs face inherent limitations that are difficult to be fully overcome through compositional and structural modification alone.In contrast,S3Es integrate the strength of complementary components to achieve a balanced and synergic enhancement in electrochemical properties(e.g.,ionic conductivity and stability window),mechanical integrity,and processability,showing great promise as next-generation SSEs.Furthermore,the application-ori-ented challenges and emerging trends in S3E research are outlined,aiming to provide strategic insights into future develop-ment of high-performance SSEs.展开更多
Reward or stress,which exists extensively,causes resilient emotional fluctuations under common situations.However,reward or stress is a typical trigger for manic or depressive episodes of bipolar disorder(BD),which is...Reward or stress,which exists extensively,causes resilient emotional fluctuations under common situations.However,reward or stress is a typical trigger for manic or depressive episodes of bipolar disorder(BD),which is corroborated by psychological theory,biological findings,and psychosocial treatment approaches[1,2].During an episode of BD,the affective aberration can be persistent and switchable,accompanied by opposite constellations of cognitive and psychomotor symptoms.Characterized by uncontrollable mood ranging in severity,duration,and polarity,to disentangle the pathophysiology mechanism of BD is to delineate the mystery of affective fluctuations driven by reward or stress.展开更多
There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with h...There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with high thermal conductivity.Furthermore,it explores the preparation of AlN_(P)/Mg-Zn-Cu composites featuring low coefficients of thermal expansion.The stir casting method was utilized to fabricate the composites and an investigation was conducted to examine their microstructure and thermal properties.Results indicate that the addition of AlN_(P)reduces the thermal expansion coefficient while maintaining relatively high thermal conductivity.Specifically,the AlN_(P)/Mg-0.5Zn-0.5Cu composite with 30wt.%AlN_(P)achieves a thermal conductivity of 132.7 W·m^(-1)·K^(-1)and a thermal expansion coefficient of 18.5×10^(-6)K^(-1),rendering it suitable for electronic packaging applications where thermal management is critical.展开更多
The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems wil...The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems will face much more serious power fading caused by chromatic dispersion(CD)combined with square-law DD and thereby significantly increases the complexity of equalization algorithms.In this paper,a 200 Gbit/s Nyquist 4-level pulse amplitude modulation(PAM4)single side-band(SSB)modulation-DD downlink scheme is designed,and a low complexity quadratic-nonlinear equalizer is proposed for this system.The computational complexity of the quadratic nonlinear equalizer is about 28%of that of the conventional Volterra nonlinear equalizer,while still exhibiting excellent nonlinear equalization ability.Simulation results for the 200 Gbit/s system with 20 km fiber transmission show that it can achieve a power budget of 29 dB,while a 30.4 dB power budget is obtained in the 50 Gbit/s experimental transmission.展开更多
High-capacity O3-type layered NiFeMn-based oxides are promising cathodes for sodium-ion batteries,though their practical deployment is constrained by the inherent limitations of Fe redox chemistry.Traditional designs ...High-capacity O3-type layered NiFeMn-based oxides are promising cathodes for sodium-ion batteries,though their practical deployment is constrained by the inherent limitations of Fe redox chemistry.Traditional designs generally enforcing stoichiometric symmetry(Ni=Mn)yield low Fe redox activity.Herein,we propose a valence engineering strategy that breaks conventional Ni/Mn stoichiometry to reconfigure Fe's local chemical environment and unlock unprecedented redox depth.Density functional theory(DFT)calculations reveal that the designed NaNi_(0.35)Fe_(0.225)Mn_(0.425)O_(2)cathode exhibits a reduced Bader charge on Fe(1.598 vs.1.638 in NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2))and elevated Fe 3d orbital energy,signifying enhanced Fe redox activity.This configuration enables an exceptional Fe^(2.60+)/Fe^(3.88+)redox(1.28 e~-per Fe),delivering a reversible capacity of184.3 mAh g^(-1)within 2-4.2 V at 0.2 C,markedly exceeding the benchmark NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(161.3 mAh g^(-1))with low reaction depth of Fe^(3.01+)/Fe^(3.61+).The intensified cationic redox reaction enables an ultrahigh energy density of 596 Whkg-1.The NaNi_(0.35)Fe_(0.225)Mn_(0.425)O_(2)cathode demonstrates robust performance over a broad temperature range from-15℃to 60℃.In situ and ex situ characterizations unveil a reversible O3■P3■OP2 phase transition with minimal volume change(1.88%)that circumvents detrimental deleterious O'3 intermediates and intragranular cracking.This work establishes valence engineering as a paradigm to consolidate cationic redox reaction in high-energy layered sodium oxide cathodes.展开更多
The large-scale integration of power electronic interface-based renewable energy with intermittency and uncertainty poses severe challenges for power system secure operation,especially frequency security.Determining t...The large-scale integration of power electronic interface-based renewable energy with intermittency and uncertainty poses severe challenges for power system secure operation,especially frequency security.Determining the system frequency regulation ability under contingency is an open problem.To bridge this gap,a unit commitment(UC)to concentrate solar power considering operational risk and frequency dynamic constraints(RFUC-CSP)is proposed in this paper.A concentrating solar power(CSP)plant with renewable energy characteristics and synchronous units is employed to improve renewable energy utilization and provide frequency support.Firstly,an analytical operational risk model is established to quantify the operational risk under renewable energy integration.Then,the frequency dynamic response characteristic of the system is considered to construct frequency security constraints.A novel RFUC-CSP framework is formulated by incorporating operational risk and frequency security constraints into the UC model,which can allocate operational flexibility of power systems by optimizing the admissible uncertainty level to reduce operational risk.The effectiveness of the proposed RFUC-CSP model is demonstrated by case studies on the modified IEEE 30-bus and IEEE RTS-79 system,and the cost-effectiveness of the CSP plant is quantified.展开更多
White Cyphochilus insulanus beetles,exhibiting both environmental camouflage display and radiative cooling functions,serve as a good prototype for biomimetic fabrication.As inspired,this work presents a femtosecond(fs...White Cyphochilus insulanus beetles,exhibiting both environmental camouflage display and radiative cooling functions,serve as a good prototype for biomimetic fabrication.As inspired,this work presents a femtosecond(fs)laser-based biomimetic fabrication strategy that takes full use of the synthesized radiative cooling nanomaterials for a groundbreaking stimuli-responsive infrared(IR)impressionistic camouflage display.The proposed technique is capable of readily transforming various substrates(quartz glass and metals including Ti,Al,Zr,and W)into self-assembled porous networks(aerogels)consisting of oxygen-vacancy-rich oxide nanoparticles.Surprisingly,the emissions of all as-prepared porous particle-networks in the radiative-cooling long-wavelength infrared(LWIR)band are above 95%,with the SiO_(2) aerogels reaching a maximum of 99.6%.Benefiting from the far-from-equilibrium thermodynamic kinetics,metastable phases of anatase TiO_(2),tetragonal zirconia(t-ZrO_(2)),and monoclinic WO_(3)(Pc)are synthesizable,opening up opportunities for exploring their optical applications.Taking the low-temperature metastable phase WO_(3)(Pc)as representative for systematic studies,it is found that(1)the ratio WO_(3)(Pc)phase to that of room-temperature phase of WO_(3)(P2_(1)/n)can be tailored by modulation of processing parameters;(2)laser synthesized aerogels with hybrid phases of WO_(3)(Pc)and WO_(3)(P2_(1)/n)have a brighter visible whiteness,higher visible/nearinfrared(NIR)spectral selectivity than the natural prototype of white Cyphochilus insulanus beetles but with comparable LWIR emittance.White WO_(3) aerogel in situ deposited during flexibly fs laser artistic patterning can blur the painting features due to its radiative cooling effect,allowing a colorful impressionistic IR display in the heating mode.What's more,invisible painting features concealed by the white deposited WO_(3) aerogel are clearly/faintly distinguishable by introducing external stimuli of a human hand and sample heating,respectively,catalyzing progress in optical encryption and selectively stimuli-responsive decryption display in the infrared band.展开更多
Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in mariti...Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in maritime shipping using the levelized cost of energy methodology.It includes a detailed comparative analysis based on essential criteria and sensitivity assessments to highlight the economic impacts of technological advancements.Key factors influencing total costs include fuel costs,carbon pricing,and energy demands for carbon capture.The findings reveal that methanol is more cost-effective than heavy fuel oil(HFO)when priced below 3000 CNY/t,assuming HFO costs 4400 CNY/t.Additionally,methanol with post-combustion carbon capture is less expensive than pre-combustion carbon capture.When carbon prices rise above 480 CNY/t,carbon capture technologies prove more economical than purchasing carbon emission allowances for HFO and liquefied natural gas.Enhanc-ing the use of exhaust gas waste heat is recommended for cost savings.Post-combustion carbon capture also shows greater efficiency,requiring about 1.1 GJ/t less energy than pre-combustion methods,leading to lower overall costs.Future research should focus on market mechanisms to stabilize fuel prices and develop less energy-intensive carbon capture technologies.This study offers critical insights into effective decarbonization strategies for advancing global maritime trade in the present and future.展开更多
Despite the high energy density,lithium metal batteries(LMBs)face significant cycling instability and safety challenges,especially at subzero temperatures.Herein,we report a rationally designed lowconcentrated electro...Despite the high energy density,lithium metal batteries(LMBs)face significant cycling instability and safety challenges,especially at subzero temperatures.Herein,we report a rationally designed lowconcentrated electrolyte system that employs a low-freezing-point diluent to compress solvation sheaths,enabling the formation of a compact anion-dominated solvation structure that enhances interfacial stability and safety.Molecular dynamics reveal the unique solvation structure with close packing of anions in this low-concentration electrolyte from the micro-mesoscopic scale.The optimized electrolyte combines cost-effectiveness,superior wettability,intrinsic nonflammability,and high stability,concurrently promoting a hybrid organic-inorganic solid electrolyte interphase(SEI)and cathode electrolyte interphase(CEI)for uniform lithium deposition.As a result,the Li‖LiFePO_(4)(LFP)full cells demonstrate stable cycling for 700 cycles at the current density of 4 C.Remarkably,the electrolyte demonstrates exceptional low-temperature performance,indicating broad operational viability.This work provides a promising electrolyte design strategy that addresses both safety and excellent electrochemical performance in high-energy-density metal-based batteries,including but not restricted to Li,Na,K and Zn multivalent ion systems.展开更多
The intrinsic insulation and drastic volume change of the red phosphorus during the 3-electron alloying process greatly limits its widespread applications in sodium-ion batteries.Here,we report a monomicelle-directed ...The intrinsic insulation and drastic volume change of the red phosphorus during the 3-electron alloying process greatly limits its widespread applications in sodium-ion batteries.Here,we report a monomicelle-directed assembly approach for controllable synthesis of monodispersed mesoporous polypyrrole(PPy)nanospheres,which allows for the shape-preserving conversion into N-doped carbon with regular mesoscopic pore and high surface area,thus affording a high dispersion of red phosphorus during melt impregnation process due to the available diffusion apertures and strong molecular chemical anchoring.Moreover,the theoretical calculations further revealed that positively polarized pyridine N atoms in N-doped mesoporous carbon nanospheres can empower comprehensive regulation of red phosphorus adsorption by strong chemical binding.Benefitting from the above advantages,the resultant red phosphorus host for sodium-ion batteries delivered an outstanding reversible capacity of 856 mAh/g with a capacity fading rate of only 0.025%per cycle during 1000 cycles at 1.0 A/g.This work provides an effective approach based on monomicelle-directed assembly engineering of carbon-based phosphorus hosts for advanced energy conversion and storage systems.展开更多
Electrochemical carbon dioxide reduction reaction(CO_(2)RR),powered by advanced technologies such as solid oxide electrolysis cells(SOEC),is a promising method to convert CO_(2) into valuable carbon-based products usi...Electrochemical carbon dioxide reduction reaction(CO_(2)RR),powered by advanced technologies such as solid oxide electrolysis cells(SOEC),is a promising method to convert CO_(2) into valuable carbon-based products using renewable electricity.The high chemical stability of CO_(2) requires catalysts to exhibit both high activity and stable electrocatalytic performance.However,catalysts that deliver high performance in CO_(2)RR are rare and still require further improvement.Here,we report a strategy that can efficiently enhance catalyst activity through Zn doping,which introduces active frustrated Lewis pairs(FLP)to improve the catalyst's ability to activate small molecules.A high current density of-1.85 A cm^(-2)at 800℃under a bias voltage of 1.5 V was achieved using the Sr_(2)Fe_(0.8)Zn_(0.2)MoO_(6-δ)(SFZn_(0.2)M)cathode with pure CO_(2) feeding gas,surpassing previously reported results for perovskite oxide cathodes.This SOEC device also demonstrates excellent stability,with negligible degradation over tests lasting up to 110 h.展开更多
Semantic segmentation for mixed scenes of aerial remote sensing and road traffic is one of the key technologies for visual perception of flying cars.The State-of-the-Art(SOTA)semantic segmentation methods have made re...Semantic segmentation for mixed scenes of aerial remote sensing and road traffic is one of the key technologies for visual perception of flying cars.The State-of-the-Art(SOTA)semantic segmentation methods have made remarkable achievements in both fine-grained segmentation and real-time performance.However,when faced with the huge differences in scale and semantic categories brought about by the mixed scenes of aerial remote sensing and road traffic,they still face great challenges and there is little related research.Addressing the above issue,this paper proposes a semantic segmentation model specifically for mixed datasets of aerial remote sensing and road traffic scenes.First,a novel decoding-recoding multi-scale feature iterative refinement structure is proposed,which utilizes the re-integration and continuous enhancement of multi-scale information to effectively deal with the huge scale differences between cross-domain scenes,while using a fully convolutional structure to ensure the lightweight and real-time requirements.Second,a welldesigned cross-window attention mechanism combined with a global information integration decoding block forms an enhanced global context perception,which can effectively capture the long-range dependencies and multi-scale global context information of different scenes,thereby achieving fine-grained semantic segmentation.The proposed method is tested on a large-scale mixed dataset of aerial remote sensing and road traffic scenes.The results confirm that it can effectively deal with the problem of large-scale differences in cross-domain scenes.Its segmentation accuracy surpasses that of the SOTA methods,which meets the real-time requirements.展开更多
LEO satellite communication systems have the characteristics of high-speed and periodic movement.The handover of user link occurs frequently,which has a serious impact on user terminal application and system capacity....LEO satellite communication systems have the characteristics of high-speed and periodic movement.The handover of user link occurs frequently,which has a serious impact on user terminal application and system capacity.To address this issue,we propose a handover strategy of LEO satellite user terminal based on multi-attribute and multi-point(MAMP)cooperation.Firstly,the satellite-user-time matrix is established by using the satellite constellation coverage and handover model.Then,combined with the visual time and signal quality,the user access matrix and satellite load matrix are extracted to determine the weight equation of the handover strategy with the channel reservation.According to the system modeling simulation,the algorithm improves the handover success rate by 2.5%,the lasted call access success rate by 3.2%,the load balancing degree by 20%,and the robustness by two orders of magnitude.展开更多
基金financially supported by the National Key R&D Program of China(2024YFF0506302)the National Natural Science Foundation of China(52372246)+1 种基金the Frontier Technologies R&D Program of Jiangsu(BF2024041)the Shanghai Engineering Research Center of Inorganic Energy Materials and Electric Power Sources(18DZ2280800)。
文摘CO_(2) hydrogenation using protonic ceramic electrolysis cells(PCECs)to produce fuel gases such as CH_(4)and CO has been considered as a promising technology for effective CO_(2) utilization.However,the long-term stability of conventional PCECs based on Y and Yb doped BaZrO_(3)-BaCeO_(3)(BCZYYb)proton conductors is severely limited by their susceptibility to carbonate formation under high concentration CO_(2) .In this work,a new type PCEC based on CO_(2) -tolerant La_(5.6)WO_(11.4-δ)(LWO)material is firstly constructed.A three-layer porous-dense-porous LWO ceramic scaffold is fabricated via a pressing,dip-coating and cosintering process,followed by Ni and La_(0.6)Sr_(0.4)CoO_(3-δ)(LSC)catalyst impregnation to ensure the chemical compatibility among materials and form an efficient PCEC-based CO_(2) hydrogenation reactor.Benefits from the synergistic catalysis of nano nickel and LWO,the reactor gets a CH_(4)selectivity of over 50%at 600℃under 20%CO_(2) concentration,and it operates stably for over 320 h at 600–650℃under high CO_(2) concentrations of 50–80%,showing no degradation in CO_(2) conversion rate or CH_(4)selectivity.Postmortem analysis demonstrates that the CO_(2) absorption characteristics of LWO and the morphological uniformity of nano nickel lead to stable CO_(2) methanation.This study provides a viable strategy for designing highly stable PCEC-based CO_(2) hydrogenation reactors.
基金the financial support from the National Natural Science Foundation of China (No. 52072390)the National High-Level Talents Special Support Program (Leading Talent of Technological Innovation)+2 种基金the China Postdoctoral Science Foundation (No. 2023M743648)the Young Scientists Fund of the National Natural Science Foundation of China (No. 52302330)the support from the Shanghai Emperor of Cleaning Hi-Tech Co.,LTD
文摘In-situ poly(1,3-dioxolane)(PDOL)-based electrolyte has received extensive attention in the research of lithium metal batteries due to its high stability to lithium anode and simple processing.However,it is still faced with defects such as low intrinsic ionic conductivity,a narrow electrochemical window,and poor thermal stability.A crosslinking and fluorination molecular design strategy toward PDOL is proposed to tackle the issues above.The amorphous crosslinked structure effectively improves ionic conductivity by inhibiting long-chain crystallization.Especially,the antioxidant–CF_(3)groups,stable crosslinked structure,and reduced terminal hydroxyl groups significantly enhance the electrochemical oxidation stability with a superb high-voltage window of 4.7 V.In addition,the designed electrolyte also exhibits obviously improved thermal stability with no deformation at 120°C for 5 min.Furthermore,the semi-solid NCM811||Li batteries exhibit a favourable capacity retention of 88.8%after 150 cycles at 0.5 C.Even assembled with NCM622 cathode working at 4.5 V,the semi-solid batteries can still show a satisfactory capacity retention of 85.3%after 100 cycles at 0.5 C.Also,a 0.1 Ah NCM811||Li pouch cell with active materials loading of 9 mg/cm2 demonstrates satisfactory cycling stability and working ability,which shows promising practical application prospects.
基金supported by the National Key Research and Development Program of China(2019YFA0905100)the National Natural Science Foundation of China(21991102,22378227).
文摘Constructing a framework carrier to stabilize protein conformation,induce high embedding efficiency,and acquire low mass-transfer resistance is an urgent issue in the development of immobilized enzymes.Hydrogen-bonded organic frameworks(HOFs)have promising application potential for embedding enzymes.In fact,no metal involvement is required,and HOFs exhibit superior biocompatibility,and free access to substrates in mesoporous channels.Herein,a facile in situ growth approach was proposed for the self-assembly of alcohol dehydrogenase encapsulated in HOF.The micron-scale bio-catalytic composite was rapidly synthesized under mild conditions(aqueous phase and ambient temperature)with a controllable embedding rate.The high crystallinity and periodic arrangement channels of HOF were preserved at a high enzyme encapsulation efficiency of 59%.This bio-composite improved the tolerance of the enzyme to the acid-base environment and retained 81%of its initial activity after five cycles of batch hydrogenation involving NADH coenzyme.Based on this controllably synthesized bio-catalytic material and a common lipase,we further developed a two-stage cascade microchemical system and achieved the continuous production of chiral hydroxybutyric acid(R-3-HBA).
基金supported in part by National Natural Science Foundation of China under Grant 62201087,Grant 62525101,in part by the National Key R&D Program of China under Grant 2023YFB2904803in part by the Guangdong Major Project of Basic and Applied Basic Research under Grant 2023B0303000001+1 种基金in part by the Natural Science Foundation of Beijing-Xiaomi Innovation Joint Foundation under Grant L243002in part by the Beijing University of Posts and Telecommunications-China Mobile Research Institute Joint Institute.
文摘As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple output(MIMO)technique to improve its capacity and coverage.Thus,testing new functions of the 5G MIMO system accurately and ef-ficiently,including beamforming(beam-tracking with movement)and multiple-user(MU)multiplexing,is a challenging task.This paper tries to construct a lab-oratorial hardware and conduct equipment-controlled field testing.Firstly,the testing scheme is presented,which is composed of the framework,the channel models and the validation methods.Then,the channel model principles are explained in detail due to its di-rect influence on the testing accuracy.Specifically,we utilize the spatial consistency and the multi-link cor-relation properties to emulate the high-speed dynamic time-varying(HDT)and the multiple-cell(MC)-MU-MIMO channels.Finally,the above testing scheme is verified in a Shanghai 5G field experiment with the practical commercial equipment and the channel em-ulator.The results show that the 5G new functions are tested accurately and efficiently by switching the channel emulation configurations.
基金supported by National Science and Technology Major Project of China(Project Number:2024ZD1300100)Fundamental Research Funds for the central universities(2024RC02)+1 种基金National Natural Science Foundation of China(62401077,62321001)Beijing Municipal Natural Science Foundation(L232003)。
文摘With the rapid growth of the low-altitude economy,the demand for typical low-altitude ap-plications has accelerated the advancement of inte-grated sensing and communications(ISAC)networks.This paper begins by analyzing representative ap-plication scenarios to clarify the core requirements of the low-altitude economy for modern ISAC net-works.By investigating the distinctive characteris-tics of ISAC networks in low-altitude environments,it presents a comprehensive analysis of key challenges and identifies four major issues:challenges in pre-cise target detection,interference management,in-consistent sensing and communication coverage,and the complexity of air-ground coordination and han-dover.Based on fundamental theories and principles,the paper proposes corresponding solutions,encom-passing advanced technologies for precise target de-tection and recognition,high-reliability networked de-tection,robust interference management,and seamless air-ground collaboration.These solutions aim to es-tablish a solid foundation for the future development of intelligent low-altitude networks and ensure effec-tive support for emerging applications.
基金supported by the National Key R&D Program of China(No.2023YFB2904803)the Beijing Natural Science Foundation(L243002),the National Natural Science Foundation of China(No.62341128)+2 种基金the Guangdong Major Project of Basic and Applied Basic Research(No.2023B0303000001)the National Natural Science Foundation of China(No.62201086)Beijing University of Posts and Telecommunications-China Mobile Research Institute Joint Innovation Center.
文摘Extremely large-scale multiple-input multiple-output(XL-MIMO)is regarded as a promis-ing technology for next-generation communication systems.However,this will expand the near-field(NF)range,rendering more users more likely to be located in the NF region.In this paper,we aim to answer two questions:What are the new characteristics of the NF channel?Is it necessary to develop new transciver techniques to maintain system performance within the NF region?To this end,we first review current NF channel models and analyze the differences between the existing 3GPP TR 38.901 channel model and the NF channel model,including the spherical wavefront and spatially non-stationarity.Then,we provide ex-amples on how these differences affect the XL-MIMO system performance in terms of beamforming gain and achievable rate.Simulation results demonstrate that,when using far-field(FF)technique under the NF channel,the maximum normalized beam gain loss is less than 3 dB for most users in the NF region de-fined by Rayleigh distance.Moreover,the achievable rate loss of beam training is less than 3%compared to that realized by NF technique.Finally,we demonstrate the necessity of employing NF transceiver techniques based on simulation results.
基金supported by the National Key Research and Development Program of China(No.2019YFA0210600)the National Natural Science Foundation of China(Nos.51922103 and 51972326)+1 种基金the Natural Science Foundation of Jiangxi Province(Nos.20224BAB204002 and GJJ211320)Jingdezhen Science and Technology Bureau(No.20212GYZD009-15)。
文摘Solid-state polymer sodium batteries(SPSBs)are promising candidates for achieving higher energy density and safe energy storage.However,interface issues between oxide cathode and solid-state polymer electrolyte are a great challenge for their commercial application.In contrast,soft sulfur-based materials feature better interface contact and chemical compatibility.Herein,an interfacial compatible polysulfide Ti_(4)P_(8)S_(29) with robust Ti-S bonding and a highly active P-S unit is tailored as a high-performance cathode for SPSBs.The Ti_(4)P_(8)S_(29) cathode possesses a three-dimensional channel structure for offering ample Na+diffusion pathways.The assembled poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)-based SPSBs deliver a discharge capacity of 136 mAh·g^(-1)at 0.5C after 200 cycles.Furthermore,a discharge capacity of 88 mAh·g^(-1)is retained after 600 cycles at a high rate of 2C,surpassing many cathode materials in SPSBs.A dual-site redox of Ti^(4+)/Ti^(3+)and S^(-)/S^(2-)is verified by X-ray photoelectron spectroscopy(XPS)and cyclic voltammetry(CV)tests.Interestingly,a refined locally-ordered amorphous structure is unveiled by in situ and ex situ characterizations.The as-formed electrode structure with lots of open channels and isotropic properties are more beneficial for ion diffusion on the interface of electrode and solid-state polymer electrolytes(SPEs),leading to faster Na+diffusion kinetics.This work proposes a strategy of modulating open-channel to boost conversion kinetics in polysulfide cathode and opens a new pathway for designing high-performance SPSBs.
基金the financial support from the National Key R&D Program of China (Grant No. 2021YFB3800300)the supports from National Key R&D Program of China (Grant No. 2022YFB3807700)+6 种基金the National Natural Science Foundation of China (Grant No. U20A20248)the supports from the National Natural Science Foundation of China (Grant Nos. W2441017, 22409103)the “Innovation Yongjiang 2035” Key R&D Program (Grant Nos. 2024Z040, 2025Z063)the National Key R&D Program of China (Grant No. 2023YFC2812700)the Natural Science Foundation of Shandong Province (Grant No. ZR2024YQ008)funding supports from the National Key R&D Program of China (Grant No. 2021YFB3800300)science and technology innovation fund for emission peak and carbon neutrality of Jiangsu province (Grant Nos. BK20220034, BK20231512)。
文摘With the widespread adoption of lithium-ion batteries(LIBs),safety concerns associated with flammable organic elec-trolytes have become increasingly critical.Solid-state lithium batteries(SSLBs),with enhanced safety and higher energy density potential,are regarded as a promising next-generation energy storage technology.However,the practical appli-cation of solid-state electrolytes(SSEs)remains hindered by several challenges,including low Li^(+)ion conductivity,poor interfacial compatibility with electrodes,unfavorable mechanical properties and difficulties in scalable manufacturing.This review systematically examines recent progress in SSEs,including inorganic types(oxides,sulfides,halides),organic types(polymers,plastic crystals,poly(ionic liquids)(PILs)),and the emerging class of soft solid-state electrolytes(S3Es),especially those based on“rigid-flexible synergy”composites and“Li+-desolvation”mechanism using porous frameworks.Critical assessment reveals that single-component SSEs face inherent limitations that are difficult to be fully overcome through compositional and structural modification alone.In contrast,S3Es integrate the strength of complementary components to achieve a balanced and synergic enhancement in electrochemical properties(e.g.,ionic conductivity and stability window),mechanical integrity,and processability,showing great promise as next-generation SSEs.Furthermore,the application-ori-ented challenges and emerging trends in S3E research are outlined,aiming to provide strategic insights into future develop-ment of high-performance SSEs.
基金supported by the National Key Research and Development Program of China(2023YFC2506200)the Leading Talent of Scientific and Technological Innovation-"Ten Thousand Talents Program"of Zhejiang Province(2021R52016).
文摘Reward or stress,which exists extensively,causes resilient emotional fluctuations under common situations.However,reward or stress is a typical trigger for manic or depressive episodes of bipolar disorder(BD),which is corroborated by psychological theory,biological findings,and psychosocial treatment approaches[1,2].During an episode of BD,the affective aberration can be persistent and switchable,accompanied by opposite constellations of cognitive and psychomotor symptoms.Characterized by uncontrollable mood ranging in severity,duration,and polarity,to disentangle the pathophysiology mechanism of BD is to delineate the mystery of affective fluctuations driven by reward or stress.
基金financially supported by National Natural Science Foundation of China(No.52175321)the Fund of Key Laboratory of High Temperature Electromagnetic Materials and Structure of MOE(No.KB202505)。
文摘There is an urgent need to develop magnesium-matrix materials that exhibit both high thermal conductivity and low thermal expansion to ensure compatibility with chips.This study aims to develop a Mg-Zn-Cu alloy with high thermal conductivity.Furthermore,it explores the preparation of AlN_(P)/Mg-Zn-Cu composites featuring low coefficients of thermal expansion.The stir casting method was utilized to fabricate the composites and an investigation was conducted to examine their microstructure and thermal properties.Results indicate that the addition of AlN_(P)reduces the thermal expansion coefficient while maintaining relatively high thermal conductivity.Specifically,the AlN_(P)/Mg-0.5Zn-0.5Cu composite with 30wt.%AlN_(P)achieves a thermal conductivity of 132.7 W·m^(-1)·K^(-1)and a thermal expansion coefficient of 18.5×10^(-6)K^(-1),rendering it suitable for electronic packaging applications where thermal management is critical.
基金ZTE Industry-University-Institute Cooperation Funds under Grant No.HC-CN-20230105001National Natural Science Foundation of China under Grant No.62001045。
文摘The 200 Gbit/s passive optical network(PON)is most likely to be the next-generation scheme following 50G PON.The costeffective direct detection(DD)system is the economical choice.However,larger-capacity DD systems will face much more serious power fading caused by chromatic dispersion(CD)combined with square-law DD and thereby significantly increases the complexity of equalization algorithms.In this paper,a 200 Gbit/s Nyquist 4-level pulse amplitude modulation(PAM4)single side-band(SSB)modulation-DD downlink scheme is designed,and a low complexity quadratic-nonlinear equalizer is proposed for this system.The computational complexity of the quadratic nonlinear equalizer is about 28%of that of the conventional Volterra nonlinear equalizer,while still exhibiting excellent nonlinear equalization ability.Simulation results for the 200 Gbit/s system with 20 km fiber transmission show that it can achieve a power budget of 29 dB,while a 30.4 dB power budget is obtained in the 50 Gbit/s experimental transmission.
基金supported by the National Natural Science Foundation of China(Grant Nos.52202282,52402054,22471283,and 52202327)Natural Science Foundation of Tianjin City(Grant Nos.22JCYBJC00040,24JCQNJC00970)。
文摘High-capacity O3-type layered NiFeMn-based oxides are promising cathodes for sodium-ion batteries,though their practical deployment is constrained by the inherent limitations of Fe redox chemistry.Traditional designs generally enforcing stoichiometric symmetry(Ni=Mn)yield low Fe redox activity.Herein,we propose a valence engineering strategy that breaks conventional Ni/Mn stoichiometry to reconfigure Fe's local chemical environment and unlock unprecedented redox depth.Density functional theory(DFT)calculations reveal that the designed NaNi_(0.35)Fe_(0.225)Mn_(0.425)O_(2)cathode exhibits a reduced Bader charge on Fe(1.598 vs.1.638 in NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2))and elevated Fe 3d orbital energy,signifying enhanced Fe redox activity.This configuration enables an exceptional Fe^(2.60+)/Fe^(3.88+)redox(1.28 e~-per Fe),delivering a reversible capacity of184.3 mAh g^(-1)within 2-4.2 V at 0.2 C,markedly exceeding the benchmark NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(161.3 mAh g^(-1))with low reaction depth of Fe^(3.01+)/Fe^(3.61+).The intensified cationic redox reaction enables an ultrahigh energy density of 596 Whkg-1.The NaNi_(0.35)Fe_(0.225)Mn_(0.425)O_(2)cathode demonstrates robust performance over a broad temperature range from-15℃to 60℃.In situ and ex situ characterizations unveil a reversible O3■P3■OP2 phase transition with minimal volume change(1.88%)that circumvents detrimental deleterious O'3 intermediates and intragranular cracking.This work establishes valence engineering as a paradigm to consolidate cationic redox reaction in high-energy layered sodium oxide cathodes.
基金supported by the National Natural Science Foundation of China General Program(No.52277106)the Project funded by China Postdoctoral Science Foundation(No.2022M721773).
文摘The large-scale integration of power electronic interface-based renewable energy with intermittency and uncertainty poses severe challenges for power system secure operation,especially frequency security.Determining the system frequency regulation ability under contingency is an open problem.To bridge this gap,a unit commitment(UC)to concentrate solar power considering operational risk and frequency dynamic constraints(RFUC-CSP)is proposed in this paper.A concentrating solar power(CSP)plant with renewable energy characteristics and synchronous units is employed to improve renewable energy utilization and provide frequency support.Firstly,an analytical operational risk model is established to quantify the operational risk under renewable energy integration.Then,the frequency dynamic response characteristic of the system is considered to construct frequency security constraints.A novel RFUC-CSP framework is formulated by incorporating operational risk and frequency security constraints into the UC model,which can allocate operational flexibility of power systems by optimizing the admissible uncertainty level to reduce operational risk.The effectiveness of the proposed RFUC-CSP model is demonstrated by case studies on the modified IEEE 30-bus and IEEE RTS-79 system,and the cost-effectiveness of the CSP plant is quantified.
基金financial support received from the Shanghai Pujiang Program(23PJ1406500)。
文摘White Cyphochilus insulanus beetles,exhibiting both environmental camouflage display and radiative cooling functions,serve as a good prototype for biomimetic fabrication.As inspired,this work presents a femtosecond(fs)laser-based biomimetic fabrication strategy that takes full use of the synthesized radiative cooling nanomaterials for a groundbreaking stimuli-responsive infrared(IR)impressionistic camouflage display.The proposed technique is capable of readily transforming various substrates(quartz glass and metals including Ti,Al,Zr,and W)into self-assembled porous networks(aerogels)consisting of oxygen-vacancy-rich oxide nanoparticles.Surprisingly,the emissions of all as-prepared porous particle-networks in the radiative-cooling long-wavelength infrared(LWIR)band are above 95%,with the SiO_(2) aerogels reaching a maximum of 99.6%.Benefiting from the far-from-equilibrium thermodynamic kinetics,metastable phases of anatase TiO_(2),tetragonal zirconia(t-ZrO_(2)),and monoclinic WO_(3)(Pc)are synthesizable,opening up opportunities for exploring their optical applications.Taking the low-temperature metastable phase WO_(3)(Pc)as representative for systematic studies,it is found that(1)the ratio WO_(3)(Pc)phase to that of room-temperature phase of WO_(3)(P2_(1)/n)can be tailored by modulation of processing parameters;(2)laser synthesized aerogels with hybrid phases of WO_(3)(Pc)and WO_(3)(P2_(1)/n)have a brighter visible whiteness,higher visible/nearinfrared(NIR)spectral selectivity than the natural prototype of white Cyphochilus insulanus beetles but with comparable LWIR emittance.White WO_(3) aerogel in situ deposited during flexibly fs laser artistic patterning can blur the painting features due to its radiative cooling effect,allowing a colorful impressionistic IR display in the heating mode.What's more,invisible painting features concealed by the white deposited WO_(3) aerogel are clearly/faintly distinguishable by introducing external stimuli of a human hand and sample heating,respectively,catalyzing progress in optical encryption and selectively stimuli-responsive decryption display in the infrared band.
基金supported by the National Key R&D Program of China(No.2022YFC3701500)the Key R&D Plan Projects of Zhejiang Province(No.2024SSYS0072)Zhejiang Provincial Natural Science Foundation(No.LDT23E0601).
文摘Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in maritime shipping using the levelized cost of energy methodology.It includes a detailed comparative analysis based on essential criteria and sensitivity assessments to highlight the economic impacts of technological advancements.Key factors influencing total costs include fuel costs,carbon pricing,and energy demands for carbon capture.The findings reveal that methanol is more cost-effective than heavy fuel oil(HFO)when priced below 3000 CNY/t,assuming HFO costs 4400 CNY/t.Additionally,methanol with post-combustion carbon capture is less expensive than pre-combustion carbon capture.When carbon prices rise above 480 CNY/t,carbon capture technologies prove more economical than purchasing carbon emission allowances for HFO and liquefied natural gas.Enhanc-ing the use of exhaust gas waste heat is recommended for cost savings.Post-combustion carbon capture also shows greater efficiency,requiring about 1.1 GJ/t less energy than pre-combustion methods,leading to lower overall costs.Future research should focus on market mechanisms to stabilize fuel prices and develop less energy-intensive carbon capture technologies.This study offers critical insights into effective decarbonization strategies for advancing global maritime trade in the present and future.
基金supported by the National Natural Science Foundation of China(No.52472219,62133007)the project ZR2024ME073 supported by Shandong Provincial Natural Science Foundationthe Shenzhen Fundamental Research Program(No.JCYJ20220530141017039)。
文摘Despite the high energy density,lithium metal batteries(LMBs)face significant cycling instability and safety challenges,especially at subzero temperatures.Herein,we report a rationally designed lowconcentrated electrolyte system that employs a low-freezing-point diluent to compress solvation sheaths,enabling the formation of a compact anion-dominated solvation structure that enhances interfacial stability and safety.Molecular dynamics reveal the unique solvation structure with close packing of anions in this low-concentration electrolyte from the micro-mesoscopic scale.The optimized electrolyte combines cost-effectiveness,superior wettability,intrinsic nonflammability,and high stability,concurrently promoting a hybrid organic-inorganic solid electrolyte interphase(SEI)and cathode electrolyte interphase(CEI)for uniform lithium deposition.As a result,the Li‖LiFePO_(4)(LFP)full cells demonstrate stable cycling for 700 cycles at the current density of 4 C.Remarkably,the electrolyte demonstrates exceptional low-temperature performance,indicating broad operational viability.This work provides a promising electrolyte design strategy that addresses both safety and excellent electrochemical performance in high-energy-density metal-based batteries,including but not restricted to Li,Na,K and Zn multivalent ion systems.
基金supported by the National Natural Science Foundation of China(Nos.52373208 and 61831021)the Shanghai Undergraduate Training Program on Innovation and Entrepreneurship(No.202310269131S).
文摘The intrinsic insulation and drastic volume change of the red phosphorus during the 3-electron alloying process greatly limits its widespread applications in sodium-ion batteries.Here,we report a monomicelle-directed assembly approach for controllable synthesis of monodispersed mesoporous polypyrrole(PPy)nanospheres,which allows for the shape-preserving conversion into N-doped carbon with regular mesoscopic pore and high surface area,thus affording a high dispersion of red phosphorus during melt impregnation process due to the available diffusion apertures and strong molecular chemical anchoring.Moreover,the theoretical calculations further revealed that positively polarized pyridine N atoms in N-doped mesoporous carbon nanospheres can empower comprehensive regulation of red phosphorus adsorption by strong chemical binding.Benefitting from the above advantages,the resultant red phosphorus host for sodium-ion batteries delivered an outstanding reversible capacity of 856 mAh/g with a capacity fading rate of only 0.025%per cycle during 1000 cycles at 1.0 A/g.This work provides an effective approach based on monomicelle-directed assembly engineering of carbon-based phosphorus hosts for advanced energy conversion and storage systems.
基金support from the National Key Research and Development Program of China(2024YFB4106400)the National Natural Science Foundation of China(22269019,52472202)Hubei Province(2024BCB073,2024EHA045).
文摘Electrochemical carbon dioxide reduction reaction(CO_(2)RR),powered by advanced technologies such as solid oxide electrolysis cells(SOEC),is a promising method to convert CO_(2) into valuable carbon-based products using renewable electricity.The high chemical stability of CO_(2) requires catalysts to exhibit both high activity and stable electrocatalytic performance.However,catalysts that deliver high performance in CO_(2)RR are rare and still require further improvement.Here,we report a strategy that can efficiently enhance catalyst activity through Zn doping,which introduces active frustrated Lewis pairs(FLP)to improve the catalyst's ability to activate small molecules.A high current density of-1.85 A cm^(-2)at 800℃under a bias voltage of 1.5 V was achieved using the Sr_(2)Fe_(0.8)Zn_(0.2)MoO_(6-δ)(SFZn_(0.2)M)cathode with pure CO_(2) feeding gas,surpassing previously reported results for perovskite oxide cathodes.This SOEC device also demonstrates excellent stability,with negligible degradation over tests lasting up to 110 h.
基金supported by the National Key Research and Development of China(No.2022YFB2503400).
文摘Semantic segmentation for mixed scenes of aerial remote sensing and road traffic is one of the key technologies for visual perception of flying cars.The State-of-the-Art(SOTA)semantic segmentation methods have made remarkable achievements in both fine-grained segmentation and real-time performance.However,when faced with the huge differences in scale and semantic categories brought about by the mixed scenes of aerial remote sensing and road traffic,they still face great challenges and there is little related research.Addressing the above issue,this paper proposes a semantic segmentation model specifically for mixed datasets of aerial remote sensing and road traffic scenes.First,a novel decoding-recoding multi-scale feature iterative refinement structure is proposed,which utilizes the re-integration and continuous enhancement of multi-scale information to effectively deal with the huge scale differences between cross-domain scenes,while using a fully convolutional structure to ensure the lightweight and real-time requirements.Second,a welldesigned cross-window attention mechanism combined with a global information integration decoding block forms an enhanced global context perception,which can effectively capture the long-range dependencies and multi-scale global context information of different scenes,thereby achieving fine-grained semantic segmentation.The proposed method is tested on a large-scale mixed dataset of aerial remote sensing and road traffic scenes.The results confirm that it can effectively deal with the problem of large-scale differences in cross-domain scenes.Its segmentation accuracy surpasses that of the SOTA methods,which meets the real-time requirements.
基金supported by the Innovation Funding of ICT,CAS under Grant(No.E261020)Jiangsu Key Research and Development Program of China(No.BE2021013-2)Zhejiang Key Research and Development Program(No.2021C01040).
文摘LEO satellite communication systems have the characteristics of high-speed and periodic movement.The handover of user link occurs frequently,which has a serious impact on user terminal application and system capacity.To address this issue,we propose a handover strategy of LEO satellite user terminal based on multi-attribute and multi-point(MAMP)cooperation.Firstly,the satellite-user-time matrix is established by using the satellite constellation coverage and handover model.Then,combined with the visual time and signal quality,the user access matrix and satellite load matrix are extracted to determine the weight equation of the handover strategy with the channel reservation.According to the system modeling simulation,the algorithm improves the handover success rate by 2.5%,the lasted call access success rate by 3.2%,the load balancing degree by 20%,and the robustness by two orders of magnitude.
