期刊文献+
共找到5,629篇文章
< 1 2 250 >
每页显示 20 50 100
Correction:Initiating Binary Metal Oxides Microcubes Electromagnetic Wave Absorber Toward Ultrabroad Absorption Bandwidth Through Interfacial and Defects Modulation
1
作者 Fushan Li Nannan Wu +8 位作者 Hideo Kimura Yuan Wang Ben Bin Xu Ding Wang Yifan Li Hassan Algadi Zhanhu Guo Wei Du Chuanxin Hou 《Nano-Micro Letters》 2025年第11期530-533,共4页
Following publication of the original article[1],the authors found that they pasted the same data when drawing XRD for sample NCO-1 and NCO-2 in Fig.2a,however,the XRD of all four samples in the manuscript was tested,... Following publication of the original article[1],the authors found that they pasted the same data when drawing XRD for sample NCO-1 and NCO-2 in Fig.2a,however,the XRD of all four samples in the manuscript was tested,and XRD raw data were kept and can be offered.The correct Fig.2 has been provided in this Correction. 展开更多
关键词 binary metal oxides ultrabroad absorption bandwidth electromagnetic wave absorber interfacial modulation defects modulation XRD microcubes
在线阅读 下载PDF
Design of Serially Concatenated Two-Level Polar Coded Modulation System with Low-Complexity
2
作者 Zhou Lin Liao Guojun +3 位作者 Xu Lei An Ran Xie Xianzhong Wang Xi 《China Communications》 2025年第1期102-110,共9页
Multilevel coding(MLC)is a commonly used polar coded modulation scheme,but challenging to implement in engineering due to its high complexity and long decoding delay for high-order modulations.To address these limitat... Multilevel coding(MLC)is a commonly used polar coded modulation scheme,but challenging to implement in engineering due to its high complexity and long decoding delay for high-order modulations.To address these limitations,a novel two-level serially concatenated MLC scheme,in which the bitlevels with similar reliability are bundled and transmitted together,is proposed.The proposed scheme hierarchically protects the two bit-level sets:the bitlevel sets at the higher level are sufficiently reliable and do not require excessive resources for protection,whereas only the bit-level sets at the lower level are encoded by polar codes.The proposed scheme has the advantages of low power consumption,low delay and high reliability.Moreover,an optimized constellation signal labeling rule that can enhance the performance is proposed.Finally,the superiority of the proposed scheme is validated through the theoretical analysis and simulation results.Compared with the bit interleaving coding modulation(BICM)scheme,under 256-quadrature amplitude modulation(QAM),the proposed scheme attains a performance gain of 1.0 dB while reducing the decoding complexity by 54.55%. 展开更多
关键词 bit-interleaved coded modulation high-order modulation multilevel coding polar codes
在线阅读 下载PDF
Large-angle stimulated Raman scattering induced by transverse density modulation
3
作者 Z.M.Huang Qing Wang +12 位作者 R.J.Cheng X.X.Li S.Y.Lv D.J.Liu Z.Y.Xu S.T.Zhang Z.J.Chen Qiang Wang C.Z.Xiao Z.J.Liu L.H.Cao C.Y.Zheng X.T.He 《Matter and Radiation at Extremes》 2025年第5期64-72,共9页
Large-angle stimulated Raman scattering(LA-SRS)in a longitudinally inhomogeneous plasma with a transverse density modulation is studied using a three-wave coupled model and numerical simulations.The simulations show t... Large-angle stimulated Raman scattering(LA-SRS)in a longitudinally inhomogeneous plasma with a transverse density modulation is studied using a three-wave coupled model and numerical simulations.The simulations show that the scattering angle of SRS in a longitudinally inhomogeneous plasma can be significantly affected by transverse density modulation.Under transverse density modulation conditions,the laser focuses into underdense regions,owing to the transversely modulated refractive index.The angle of LA-SRS,neither a purely 90° angle side scattering nor purely backscattering,is almost consistent with the specific angle at which the density inhomogeneity vanishes.In modulated plasmas,the nonuniform distribution of laser intensity shifts the regions of scattering and gain compared with those in uniform plasmas,ultimately affecting the laser transmission.SRS is suppressed in weakly modulated regimes,whereas it is enhanced under strong modulation conditions,and a theoretical criterion distinguishing between strong and weak modulation is established. 展开更多
关键词 longitudinally inhomogeneous plasma transverse density modulation numerical simulationsthe transversely modulated refractive indexthe large angle stimulated Raman scattering three wave coupled model transverse density modulationunder
在线阅读 下载PDF
Spin-dependent amplitude and phase modulation with multifold interferences via single-layer diatomic all-silicon metasurfaces 被引量:2
4
作者 Hui Li Chenhui Zhao +6 位作者 Jie Li Hang Xu Wenhui Xu Qi Tan Chunyu Song Yun Shen Jianquan Yao 《Opto-Electronic Science》 2025年第3期2-15,共14页
Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarizat... Diatomic metasurfaces designed for interferometric mechanisms possess significant potential for the multidimensional manipulation of electromagnetic waves,including control over amplitude,phase,frequency,and polarization.Geometric phase profiles with spin-selective properties are commonly associated with wavefront modulation,allowing the implementation of conjugate strategies within orthogonal circularly polarized channels.Simultaneous control of these characteristics in a single-layered diatomic metasurface will be an apparent technological extension.Here,spin-selective modulation of terahertz(THz)beams is realized by assembling a pair of meta-atoms with birefringent effects.The distinct modulation functions arise from geometric phase profiles characterized by multiple rotational properties,which introduce independent parametric factors that elucidate their physical significance.By arranging the key parameters,the proposed design strategy can be employed to realize independent amplitude and phase manipulation.A series of THz metasurface samples with specific modulation functions are characterized,experimentally demonstrating the accuracy of on-demand manipulation.This research paves the way for all-silicon meta-optics that may have great potential in imaging,sensing and detection. 展开更多
关键词 diatomic metasurface geometric phase complex amplitude modulation spin-selective
在线阅读 下载PDF
Bioinspired smart dual-layer hydrogels system with synchronous solar and thermal radiation modulation for energy-saving all-season temperature regulation 被引量:1
5
作者 Meng-Chen Huang Chao-Hua Xue +8 位作者 Zhongxue Bai Jun Cheng Yong-Gang Wu Chao-Qun Ma Li Wan Long Xie Hui-Di Wang Bing-Ying Liu Xiao-Jing Guo 《Journal of Energy Chemistry》 2025年第2期175-190,I0005,共17页
All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management... All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons. 展开更多
关键词 Thermochromic hydrogel Self-adaptive thermal management Radiative cooling Spectral modulation ENERGY-SAVING
在线阅读 下载PDF
Ion-modulation optoelectronic neuromorphic devices:mechanisms,characteristics,and applications 被引量:1
6
作者 Xiaohan Meng Runsheng Gao +1 位作者 Xiaojian Zhu Run-Wei Li 《Journal of Semiconductors》 2025年第2期24-36,共13页
The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorph... The traditional von Neumann architecture faces inherent limitations due to the separation of memory and computa-tion,leading to high energy consumption,significant latency,and reduced operational efficiency.Neuromorphic computing,inspired by the architecture of the human brain,offers a promising alternative by integrating memory and computational func-tions,enabling parallel,high-speed,and energy-efficient information processing.Among various neuromorphic technologies,ion-modulated optoelectronic devices have garnered attention due to their excellent ionic tunability and the availability of multi-dimensional control strategies.This review provides a comprehensive overview of recent progress in ion-modulation optoelec-tronic neuromorphic devices.It elucidates the key mechanisms underlying ionic modulation of light fields,including ion migra-tion dynamics and capture and release of charge through ions.Furthermore,the synthesis of active materials and the proper-ties of these devices are analyzed in detail.The review also highlights the application of ion-modulation optoelectronic devices in artificial vision systems,neuromorphic computing,and other bionic fields.Finally,the existing challenges and future direc-tions for the development of optoelectronic neuromorphic devices are discussed,providing critical insights for advancing this promising field. 展开更多
关键词 ion migration optoelectronic modulation optoelectronic device neuromorphic computing artificial vision system
在线阅读 下载PDF
Cation and anion modulation activates lattice oxygen for enhanced oxygen evolution 被引量:1
7
作者 Mingxing Chen Zihe Du +8 位作者 Nian Liu Huijie Li Jing Qi Enbo Shangguan Jing Li Jiahao Cao Shujiao Yang Wei Zhang Rui Cao 《Chinese Journal of Catalysis》 2025年第2期282-291,共10页
Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy... Oxygen evolution reaction(OER)is often regarded as a crucial bottleneck in the field of renewable energy storage and conversion.To further accelerate the sluggish kinetics of OER,a cation and anion modulation strategy is reported here,which has been proven to be effective in preparing highly active electrocatalyst.For example,the cobalt,sulfur,and phosphorus modulated nickel hydroxide(denoted as NiCoPSOH)only needs an overpotential of 232 mV to reach a current density of 20 mA cm^(–2),demonstrating excellent OER performances.The cation and anion modulation facilitates the generation of high-valent Ni species,which would activate the lattice oxygen and switch the OER reaction pathway from conventional adsorbate evolution mechanism to lattice oxygen mechanism(LOM),as evidenced by the results of electrochemical measurements,Raman spectroscopy and differential electrochemical mass spectrometry.The LOM pathway of NiCoPSOH is further verified by the theoretical calculations,including the upshift of O 2p band center,the weakened Ni–O bond and the lowest energy barrier of rate-limiting step.Thus,the anion and cation modulated catalyst NiCoPSOH could effectively accelerate the sluggish OER kinetics.Our work provides a new insight into the cation and anion modulation,and broadens the possibility for the rational design of highly active electrocatalysts. 展开更多
关键词 Oxygen evolution reaction ELECTROCATALYSIS Lattice oxygen mechanism High-valent metal species Cation and anion modulation
在线阅读 下载PDF
Defect Engineering with Rational Dopants Modulation for High‑Temperature Energy Harvesting in Lead‑Free Piezoceramics
8
作者 Kaibiao Xi Jianzhe Guo +2 位作者 Mupeng Zheng Mankang Zhu Yudong Hou 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期87-101,共15页
High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,inclu... High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless sensors.However,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported before.Herein,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese doping.Due to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese ions.The HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments. 展开更多
关键词 Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester
在线阅读 下载PDF
Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation
9
作者 Younong Li Li Dan +2 位作者 Jing Peng Qidong Yang Fuqiang Yang 《Atmospheric and Oceanic Science Letters》 2025年第1期32-38,共7页
El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation an... El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further investigation.To investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 models.The results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the future.The higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in variability.Carbon flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through temperature.This occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures. 展开更多
关键词 Carbon variability ENSO modulation CMIP6 models
在线阅读 下载PDF
Multi-frequency formation mechanism and modulation strategy of self-priming enhanced submerged pulsed waterjet
10
作者 Haojie Jia Yanwei Liu +6 位作者 Weiqin Zuo Hongkai Han Ping Chang Mohammad Waqar Ali Asad Guozhong Hu Jian Miao Hani SMitri 《International Journal of Mining Science and Technology》 2025年第2期175-189,共15页
Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure throug... Under submerged conditions, compared with traditional self-excited oscillating pulsed waterjets(SOPWs), annular fluid-enhanced self-excited oscillating pulsed waterjets(AFESOPWs) exhibit a higher surge pressure through self-priming. However, their pressure frequency and cavitation characteristics remain unclear, resulting in an inability to fully utilize resonance and cavitation erosion to break coal and rock. In this study, high-frequency pressure testing, high-speed photography, and large eddy simulation(LES) are used to investigate the distribution of the pressure frequency band, evolution law of the cavitation cloud, and its regulation mechanism of a continuous waterjet, SOPW, and AFESOPW. The results indicated that the excitation of the plunger pump, shearing layer vortex, and bubble collapse corresponded to the three high-amplitude frequency bands of the waterjet pressure. AFESOPWs have an additional self-priming frequency that can produce a larger amplitude under a synergistic effect with the second high-amplitude frequency band. A better cavitation effect was produced after self-priming the annulus fluid, and the shedding frequency of the cavitation clouds of the three types of waterjets was linearly related to the cavitation number. The peak pressure of the waterjet and cavitation erosion effect can be improved by modulating the waterjet pressure oscillation frequency and cavitation shedding frequency. 展开更多
关键词 MULTI-FREQUENCY modulation SELF-PRIMING Submerged waterjet CAVITATION
在线阅读 下载PDF
Nanosizing enhancement of hydrogen storage performance and mechanism in Mg-based materials:Nano-substrate modulation,nano-catalyst construction,and nano-catalytic mechanisms
11
作者 Duode Zhao Xiaojiang Hou +8 位作者 Yu Ge Dongfeng Sun Danting Li Chenlu Wang Xinlei Xie Peixuan Zhu Xiaohui Ye Guoquan Suo Yanling Yang 《Journal of Energy Chemistry》 2025年第10期609-636,共28页
The magnesium-based materials are acknowledged as one of the most promising solid-state hydrogen storage mediums,attributed to their superior hydrogen storage capacity.Nevertheless,challenges such as sluggish kinetics... The magnesium-based materials are acknowledged as one of the most promising solid-state hydrogen storage mediums,attributed to their superior hydrogen storage capacity.Nevertheless,challenges such as sluggish kinetics,thermodynamic stability,inadequate cycling stability,and difficulties in activation impede the commercial utilization of Mg-based composites.Research indicates that reducing material dimensions to the nanoscale represents an efficacious strategy to address these issues.In this work,we systematically analyze the impact of nanosizing on Mg-based composites from three perspectives:nano-substrate modulation,nano-catalyst construction,and nano-catalytic mechanism.This analysis aims to provide guidance for the optimization and development of nanosizing strategies.For the regulation of nanosizing of Mg-based composites,the nanosizing of multi-element micro-alloyed Mg-rich systems,the integrated synthesis of multi-element multi-component nano-catalysts,and the coexistence of multiple nano-catalytic mechanisms are proposed in the light of the current state of the art research,artificial intelligence technology,and advanced characterization technology to achieve efficient,multidimensional,and simultaneous regulation of the hydrogen storage performance of Mg-based composites.This paper also envisions future directions and potential applications,emphasizing the importance of interdisciplinary approaches that integrate material science,chemistry,and computational modeling to overcome existing limitations and unlock the full potential of Mg-based hydrogen storage technologies. 展开更多
关键词 Nanosizing Mg-based materials Substrate modulation Catalyst Catalytic mechanism
在线阅读 下载PDF
Microenvironment modulation around frustrated Lewis pairs in Ce-based metal-organic frameworks for efficient catalytic hydrogenation
12
作者 Xinmeng Xu Zuoshuai Xi +6 位作者 Hongyi Gao Danfeng Zhao Zhiyuan Liu Tao Ban Jingjing Wang Shunzheng Zhao Ge Wang 《Chinese Journal of Catalysis》 2025年第8期59-72,共14页
The development of solid frustrated Lewis pairs(FLPs)catalysts with porous structures is a promising strategy for advancing green hydrogenation technologies and has garnered significant attention.Leveraging the divers... The development of solid frustrated Lewis pairs(FLPs)catalysts with porous structures is a promising strategy for advancing green hydrogenation technologies and has garnered significant attention.Leveraging the diverse oxidation states and structural tunability of cerium-based metal-organic frameworks(Ce-MOFs),this study employed a competitive coordination strategy utilizing a single carboxylate functional group ligand to construct a series of MOF-808-X(X=-NH_(2),-OH,-Br,and-NO_(2))featuring rich solid-state FLPs for hydrogenation of unsaturated olefins.The-X functional group serves as a microenvironment,enhancing hydrogenation activity by modulating the electronic properties and acid-base characteristics of the FLP sites.The unique redox properties of elemental cerium facilitate the exposure of unsaturated Ce sites(Ce-CUS,Lewis acid(LA))and adjacent Ce-OH(Lewis base(LB))sites within the MOFs,generating abundant solid-state FLP(Ce-CUS/Ce-OH)sites.Experimental results demonstrate that Ce-CUS and Ce-OH interact with theσandσ^(*)orbitals of H-H,and this"push-pull"synergy promotes heterolytic cleavage of the H-H bond.The lone pair electrons of the electron-donating functional group are transmitted through the molecular backbone to the LB site,thereby increasing its strength and reducing the activation energy required for H_(2)heterolytic cleavage.Notably,at 100℃and 2 MPa H_(2),MOF-808-NH_(2)achieves complete conversion of styrene and dicyclopentadiene,significantly outperforming MOF-808.Based on in-situ analysis and density functional theory calculations,a plausible reaction mechanism is proposed.This research enriches the theoretical framework for unsaturated olefin hydrogenation catalysts and contributes to the development of efficient catalytic systems. 展开更多
关键词 Frustrated Lewis pairs Microenvironment modulation Defect Ce-based metal-organic frameworks Catalyst Hydrogenation
在线阅读 下载PDF
Solidification cracking restraining mechanism of laser-welded aluminum alloy joints using power modulation technique
13
作者 Jing HAN Yu SHI +4 位作者 Gang ZHANG You-wei XU Volodymyr KORZHYK Wang-yun LE Feng-xian DAI 《Transactions of Nonferrous Metals Society of China》 2025年第8期2521-2535,共15页
The 7075 aluminum alloy was subjected to power-modulated laser welding using a full-domain power modulation(FDPM)laser oscillating welding system.Three different power modes were utilized:constant power(CP),gradient p... The 7075 aluminum alloy was subjected to power-modulated laser welding using a full-domain power modulation(FDPM)laser oscillating welding system.Three different power modes were utilized:constant power(CP),gradient power(GP),and alternating power(AP)modes.The impact of different power modes on joint crack sensitivity,microstructure,and residual stress was assessed.The results demonstrate that joint welded with the AP mode exhibits the lowest sensitivity to solidification cracking(with mean crack sensitivity of 18.3%),and the smallest average grain size in the fusion zone of the weld seam(80μm).Additionally,it shows the highest microhardness(HV 113)and the narrowest softening region(3.5 cm).Furthermore,the joint displays the lowest residual stress and cooling rate,which is the reason for its minimal crack sensitivity. 展开更多
关键词 aluminum alloy laser welding OSCILLATING crack sensitivity power modulation
在线阅读 下载PDF
Sustainable Carbon-Based Catalyst Materials Derived From Lignocellulosic Biomass for Energy Storage and Conversion:Atomic Modulation and Properties Improvement
14
作者 Wei Li Ying Xu +4 位作者 Guanhua Wang Ting Xu Kui Wang Shangru Zhai Chuanling Si 《Carbon Energy》 2025年第5期55-100,共46页
Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic ap... Carbon electrocatalyst materials based on lignocellulosic biomass with multi-components,various dimensions,high carbon content,and hierarchical morphology structures have gained great popularity in electrocatalytic applications recently.Due to the catalytic deficiency of neutral carbon atoms,the usage of single lignocellulosic-based carbon materials in electrocatalysis involving energy storage and conversion presents unsatisfactory applicability.However,atomic-level modulation of lignocellulose-based carbon materials can optimize the electronic structures,charge separation,transfer processes,and so forth,which results in substantially enhanced electrocatalytic performance of carbon-based catalysts.This paper reviews the recent advances in the rational design of lignocellulosic-based carbon materials as electrocatalysts from an atomic-level perspective,such as self/external heteroatom doping and metal modification.Then,through systematic discussion of the design principles and reaction mechanisms of the catalysts,the applications of the prepared lignocellulosic-based catalysts in rechargeable batteries and electrocatalysis are reviewed.Finally,the challenges in improving the catalytic performance of lignocellulosic-based carbon materials as electrocatalysts and the prospects in diverse applications are reviewed.This review contributes to the synthesis strategy of lignocellulose-based carbon electrocatalysts via atomic-level modulation,which in turn promotes the lignocellulose valorization for energy storage and conversion. 展开更多
关键词 atomic modulation carbon materials ELECTROCATALYSIS lignocellulosic biomass rechargeable batteries
在线阅读 下载PDF
Stabilizing Cu^(+)active sites by small molecule modulation on copper electrocatalyst for boosting semi-hydrogenation of alkynes in water
15
作者 Ran Li Hui Li +7 位作者 Jing Luo Jie Zhou Qi Sui Yujie Gao Hongshuai Zheng Lixin Xia Fei Li Yi Jiang 《Journal of Energy Chemistry》 2025年第3期800-807,共8页
Selective electrocatalytic semi-hydrogenation(ECSH)of alkynes in water using Cu catalysts is highly relevant for the production of value-added chemicals.However,achieving high olefin selectivity still poses extreme ch... Selective electrocatalytic semi-hydrogenation(ECSH)of alkynes in water using Cu catalysts is highly relevant for the production of value-added chemicals.However,achieving high olefin selectivity still poses extreme challenges due to the susceptibility of the copper cathode in a reduction environment.Herein,a small molecule modulation electrodeposition strategy is introduced that regulates the structure of Cubased materials through modification with citric acid(CA)ligands,aiming for highly active and selective ECSH.The as-prepared EDCu-CA electrode achieves more than 97%alkyne conversion and 99%olefin selectivity.In-situ Raman and Auger electron spectroscopy(AES)data provide evidence that active Cu^(+)sites can stably exist in the EDCu-CA during the catalytic process.Density functional theory(DFT)calculations indicate that the modulation by CA contributes to maintaining Cu in a positive valence state,and Cu^(+)can inhibit the over-hydrogenation of olefins.Moreover,by utilizing a large-area electrode for longterm electrolysis,g-level conversion and a 92%separation yield of olefin can be achieved,demonstrating a viable application prospect.This study offers a promising route for designing Cu-based catalysts for the highly selective electrocata lytic conversion of organic substrates to value-added chemicals in water. 展开更多
关键词 Electrocatalysis Cu catalysts Alkyne semi-hydrogenation Citric acid modulation Stabilizing Cu^(+)
在线阅读 下载PDF
Adhesion of 2D Materials: Measurement and Modulation
16
作者 Na Li Hongrong Wu +1 位作者 Changwei Sun Junhua Zhao 《Acta Mechanica Solida Sinica》 2025年第2期252-274,共23页
Two-dimensional(2D)materials are promising for next-generation electronic devices and systems due to their unique physical properties.The interfacial adhesion plays a vital role not only in the synthesis,transfer and ... Two-dimensional(2D)materials are promising for next-generation electronic devices and systems due to their unique physical properties.The interfacial adhesion plays a vital role not only in the synthesis,transfer and manipulation of 2D materials but also in the manufacture,integration and performance of the functional devices.However,the atomic thickness and limited lateral dimensions of 2D materials make the accurate measurement and modulation of their interfacial adhesion energy challenging.In this review,the recent advances in the measurement and modulation of the interfacial adhesion properties of 2D materials are systematically combed.Experimental methods and relative theoretical models for the adhesion measurement of 2D materials are summarized,with their scope of application and limitations discussed.The measured adhesion energies between 2D materials and various substrates are described in categories,where the typical adhesion modulation strategies of 2D materials are also introduced.Finally,the remaining challenges and opportunities for the interfacial adhesion measurement and modulation of 2D materials are presented.This paper provides guidance for addressing the adhesion issues in devices and systems involving 2D materials. 展开更多
关键词 2D materials ADHESION MEASUREMENT modulation
原文传递
Periodic modulation of adiabatic dynamics in non-reciprocal Landau-Zener systems
17
作者 Rong Chang Sheng-Chang Li 《Chinese Physics B》 2025年第3期259-264,共6页
The control of adiabatic dynamics is essential for quantum manipulation.We investigate the effects of both periodic modulating field and linear sweeping field on adiabatic dynamics based on a non-reciprocal Landau-Zen... The control of adiabatic dynamics is essential for quantum manipulation.We investigate the effects of both periodic modulating field and linear sweeping field on adiabatic dynamics based on a non-reciprocal Landau-Zener model with periodic modulation.We obtain adiabatic phase diagrams in the(ω,δ)parameter space,where the adiabatic region is bounded by the modulating frequencyωgreater than a critical valueω_(c) and the non-reciprocal parameterδless than one.The results show that the adiabaticity of the system is not sensitive to the modulating amplitude.We find that the critical modulating frequency can be expressed as a power function of the modulating period number or the sweeping rate.Our findings suggest that one can change the adiabatic region or improve the adiabaticity by adjusting the parameters of both the modulating and the sweeping fields,which provides an effective means to flexibly control the adiabatic dynamics of non-reciprocal systems. 展开更多
关键词 ADIABATICITY non-reciprocity Landau-Zener tunneling periodic modulation
原文传递
Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries
18
作者 Xinyuan Wang Fan Zhang +5 位作者 Xingyu Zhou Qian Wang Changyu Liu Yangyang Liu Hui Wang Xiaojie Liu 《Journal of Energy Chemistry》 2025年第1期509-521,共13页
Na_(3)V_(2)(PO_(4))_(2)O_(2)F (VP) is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific capacity.Density functional theory (DFT) and finite el... Na_(3)V_(2)(PO_(4))_(2)O_(2)F (VP) is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific capacity.Density functional theory (DFT) and finite element simulations show that incorporating SO_(4)^(2-)into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge cycles.Consequently,the average Na+diffusion coefficient of Na_(3)V_(2)(PO_(4))_(1.95)(SO_(4))_(0.05)O_(2)F(VPS-1) is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g^(-1)) and cycling stability (111.0 mAh g^(-1)capacity after 1000 cycles at 10 C current density) for VPS-1.VPS-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 min.The assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%. 展开更多
关键词 Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode
在线阅读 下载PDF
Index Modulation Aided OTFS for SCMA System
19
作者 He Chunlin Xiao Lixia +3 位作者 Li Shuo Liu Weidan Xiao Pei Jiang Tao 《China Communications》 2025年第8期19-28,共10页
In this paper,an index modulation(IM)aided uplink orthogonal time frequency space modulation(OTFS)structure for sparse code multiple access(SCMA)is proposed.To be more specific,the information bits are firstly partiti... In this paper,an index modulation(IM)aided uplink orthogonal time frequency space modulation(OTFS)structure for sparse code multiple access(SCMA)is proposed.To be more specific,the information bits are firstly partitioned for transmit antenna(TA)selection and sparse codeword mapping,respectively.Subsequently,the codewords deployed on the 2-dimensional(2D)delay-Doppler(DD)plane are transmitted by the selected TA,and the superimposed signals are jointly detected at the receiver.Furthermore,a low-complexity zero-embedded expectation propagation(ZE-EP)detector is conceived,where the codebooks are extended with zero vectors to reflect the silent indices.The simulation results demonstrate that the proposed IM-OTFS-SCMA system is capable of providing significant performance gain over the OTFS-SCMA counterpart. 展开更多
关键词 expectation propagation algorithm index modulation message passing algorithm OTFS SCMA
在线阅读 下载PDF
Dynamic hybrid visual-thermal multimodal perception neuromorphic devices based on defect modulation of electrospun nanofibers
20
作者 Shengkai Wen Yanan Liu +3 位作者 Yi Li Liang Xie Jun Li Jianhua Zhang 《International Journal of Extreme Manufacturing》 2025年第2期749-761,共13页
Neuromorphic devices,inspired by the intricate architecture of the human brain,have garnered recognition for their prodigious computational speed and sophisticated parallel computing capabilities.Vision,the primary mo... Neuromorphic devices,inspired by the intricate architecture of the human brain,have garnered recognition for their prodigious computational speed and sophisticated parallel computing capabilities.Vision,the primary mode of external information acquisition in living organisms,has garnered substantial scholarly interest.Notwithstanding numerous studies simulating the retina through optical synapses,their applications remain circumscribed to single-mode perception.Moreover,the pivotal role of temperature,a fundamental regulator of biological activities,has regrettably been relegated to the periphery.To address these limitations,we proffer a neuromorphic device endowed with multimodal perception,grounded in the principles of light-modulated semiconductors.This device seamlessly accomplishes dynamic hybrid visual and thermal multimodal perception,featuring temperature-dependent paired pulse facilitation properties and adaptive storage.Crucially,our meticulous examination of transfer curves,capacitance–voltage(C–V)tests,and noise measurements provides insights into interface and bulk defects,elucidating the physical mechanisms underlying adaptive storage and other functionalities.Additionally,the device demonstrates a variety of synaptic functionalities,including filtering properties,Ebbinghaus curves,and memory applications in image recognition.Surprisingly,the digital recognition rate achieves a remarkable value of 98.8%. 展开更多
关键词 neuromorphic devices electrospinning defect modulation dynamic hybrid multimodal perception adaptive storage
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部