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Compact RF linear accelerator for electron beam irradiation applications at PBP-CMU Electron Linac Laboratory
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作者 Monchai Jitvisate Pittaya Apiwattanakul +3 位作者 Noppadol Kangrang Jatuporn Saisut Chitrlada Thongbai Sakhorn Rimjaem 《Nuclear Science and Techniques》 2025年第4期45-58,共14页
A 4 MeV RF linear accelerator for electron beam irradiation applications has been developed at the PBP-CMU Electron Linac Laboratory,Thailand.The system has been reengineered using a decommissioned medical linear acce... A 4 MeV RF linear accelerator for electron beam irradiation applications has been developed at the PBP-CMU Electron Linac Laboratory,Thailand.The system has been reengineered using a decommissioned medical linear accelerator.The main components include a thermionic DC electron gun,an RF linear accelerator,a beam diagnostic chamber,and a beam exit window for electron beam irradiation.Therefore,reengineering must be performed based on the characteristics of the electron beam and its dynamics throughout the system.In this study,the electron beam current density emitted from the cathode was calculated based on the thermionic emission theory,and the result was used to produce the electron beam distribution in the gun using CST Studio Suite^(■)software.The properties of the electron beam and its acceleration in the linear accelerator and downstream diagnostic section were studied using the ASTRA electron beam dynamics simulation code,with the aim of producing an electron beam with an average energy of 4 MeV at the linear accelerator exit.The transverse beam profile and electron deposition dose in the ambient environment were calculated using Geant4 Monte Carlo simulation software to estimate the beam performance for the irradiation experiments.The parameters studied can be used as guidelines for machine operation and future experimental plans. 展开更多
关键词 Thermionic electron gun RF linear accelerator Electron dynamics simulation Monte Carlo simulation Electron beam irradiation Electron beam processing Deposition dose
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Impact attenuation mechanism of single/double-layer potting structures of MEMS devices under continuous double-pulse impact
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作者 Hao'nan Guo Yunbo Shi +4 位作者 Rui Zhao Yu'nan Chen Peng Zhang Liang Chen Tao Guo 《Defence Technology(防务技术)》 2025年第6期104-114,共11页
High-overload shocks are very likely to cause damage to the microstructure of MEMS devices, especially the continuous multiple high-overload shocks generated by the penetration of the multilayer target environment pos... High-overload shocks are very likely to cause damage to the microstructure of MEMS devices, especially the continuous multiple high-overload shocks generated by the penetration of the multilayer target environment pose more stringent challenges to its protective structure. In this study, the kinetic response model of the protective structure under single-pulse and continuous double-pulse impact is established,and a continuous double-pulse high overload impact test impact platform based on the sleeve-type bullet is constructed, and the protective performance of the multi-layer structure under multi-pulse is analyzed based on the acceleration decay ratio, and the results show that the protective performance of the structure has a positive correlation with its thickness, and it is not sensitive to the change of the load of the first impact;the first impact under double-pulse impact will cause damage to the microstructure through the superposition of the second impact. The first impact under double-pulse impact will cause an increase in the overload amplitude of the second impact through superposition;compared with the single-layer structure, the acceleration attenuation ratio of the double-layer structure can be increased by up to 26.13%, among which the epoxy-polyurethane combination has the best protection performance, with an acceleration attenuation ratio of up to 44.68%. This work provides a robust theoretical foundation and experimental basis for the reliable operation of MEMS devices, as well as for the design of protective structures in extreme environments. 展开更多
关键词 Continuous double pulse Protective structure Attenuation ratio MEMS devices
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Distributed waveform generation and digitization system based on transparent transmission
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作者 Lei Lang Kai Chen +2 位作者 Dou Zhu Jing Wang Yi-Chen Yang 《Nuclear Science and Techniques》 2025年第3期60-68,共9页
Waveform generation and digitization play essential roles in numerous physics experiments.In traditional distributed systems for large-scale experiments,each frontend node contains an FPGA for data preprocessing,which... Waveform generation and digitization play essential roles in numerous physics experiments.In traditional distributed systems for large-scale experiments,each frontend node contains an FPGA for data preprocessing,which interfaces with various data converters and exchanges data with a backend central processor.However,the streaming readout architecture has become a new paradigm for several experiments benefiting from advancements in data transmission and computing technologies.This paper proposes a scalable distributed waveform generation and digitization system that utilizes fiber optical connections for data transmission between frontend nodes and a central processor.By utilizing transparent transmission on top of the data link layer,the clock and data ports of the converters in the frontend nodes are directly mapped to the FPGA firmware at the backend.This streaming readout architecture reduces the complexity of frontend development and maintains the data conversion in proximity to the detector.Each frontend node uses a local clock for waveform digitization.To translate the timing information of events in each channel into the system clock domain within the backend central processing FPGA,a novel method is proposed and evaluated using a demonstrator system. 展开更多
关键词 Transparent transmission Waveform generation Waveform digitization Distributed system
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Remote picometric acoustic sensing via ultrastable laser homodyne interferometry
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作者 Yoon-Soo Jang Dong Il Lee +2 位作者 Jaime Flor Flores Wenting Wang Chee Wei Wong 《Advanced Photonics Nexus》 2025年第4期54-62,共9页
Acoustic detection has many applications across science and technology from medicine to imaging and communications.However,most acoustic sensors have a common limitation in that the detection must be near the acoustic... Acoustic detection has many applications across science and technology from medicine to imaging and communications.However,most acoustic sensors have a common limitation in that the detection must be near the acoustic source.Alternatively,laser interferometry with picometer-scale motional displacement detection can rapidly and precisely measure sound-induced minute vibrations on remote surfaces.Here,we demonstrate the feasibility of sound detection up to 100 kHz at remote sites with≈60 m optical path length via laser homodyne interferometry.Based on our ultrastable hertz linewidth laser with 10-15 fractional stability,our laser interferometer achieves 0.5 pm/Hz1/2 displacement sensitivity near 10 kHz,bounded only by laser frequency noise over 10 kHz.Between 140 Hz and 15 kHz,we achieve a homodyne acoustic sensing sensitivity of subnanometer/Pascal across our conversational frequency overtones.The minimal sound pressure detectable over 60 m optical path length is≈2 mPa,with dynamic ranges over 100 dB.With the demonstrated standoff picometric distance metrology,we successfully detected and reconstructed musical scores of normal conversational volumes with high fidelity.The acoustic detection via this precision laser interferometer could be applied to selective area sound sensing for remote acoustic metrology,optomechanical vibrational motion sensing,and ultrasensitive optical microphones at the laser frequency noise limits. 展开更多
关键词 homodyne interferometry displacement measurement acoustic sensing remote sensing ultrastable laser
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In-situ Ultrafast Transmission Electron Microscopy:Advancing Ultrafast Dynamics Research under Multi-Field Coupling at the Nanoscale
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作者 Shaozheng Ji Lenan Chen Xuewen Fu 《Chinese Physics Letters》 2025年第1期99-101,共3页
In recent years,the development of ultrafast transmission electron microscopy(UTEM)has created new opportunities for studying dynamic processes at the nanoscale with unprecedented temporal resolution.~([1–3])The sign... In recent years,the development of ultrafast transmission electron microscopy(UTEM)has created new opportunities for studying dynamic processes at the nanoscale with unprecedented temporal resolution.~([1–3])The significant advances in femtosecond and even attosecond temporal resolution are achieved through the integration of the pump-probe principle with transmission electron microscopy(TEM). 展开更多
关键词 resolution. ELECTRON COUPLING
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Unveiling the Gel_(2)-Assisted Oriented Growth of Perovskite Crystallite for High-Performance Flexible Sn Perovskite Solar Cells
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作者 Huagui Lai Selina Olthof +7 位作者 Shengqiang Ren Radha K.Kothandaraman Matthias Diethelm Quentin Jeangros Roland Hany Ayodhya N.Tiwari Dewei Zhao Fan Fu 《Energy & Environmental Materials》 2025年第1期173-181,共9页
Tin perovskites are emerging as promising alternatives to their lead-based counterparts for high-performance and flexible perovskite solar cells.However,their rapid crystallization often leads to inadequate film quali... Tin perovskites are emerging as promising alternatives to their lead-based counterparts for high-performance and flexible perovskite solar cells.However,their rapid crystallization often leads to inadequate film quality and poor device performance.In this study,the role of GeI_(2) as an additive is investigated for controlling the nucleation and crystallization processes of formamidinium tin triiodide(FASnI3).The findings reveal the preferential formation of a Ge-rich layer at the bottom of the perovskite film upon the introduction of GeI_(2).It is proposed that the initial formation of the Ge complex acts as a crystallization regulator,promoting oriented growth of subsequent FASnI3 crystals and enhancing overall crystallinity.Through the incorporation of an optimal amount of GeI_(2),flexible Sn perovskite solar cells with an efficiency of 10.8%were achieved.Furthermore,it was observed that the GeI_(2) additive ensures a remarkable shelf-life for the devices,with the rigid cells retaining 91%of their initial performance after more than 13800 h of storage in an N_(2) gas environment.This study elucidates the mechanistic role of GeI_(2) in regulating the nucleation and crystallization process of tin perovskites,providing valuable insights into the significance of additive engineering for the development of high-performance flexible tin perovskite solar cells. 展开更多
关键词 additive crystallization FLEXIBLE LEAD-FREE Sn perovskite solar cells
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Mapping ultrafast timing jitter in dispersion- managed 89 GHz frequency microcombs via self-heterodyne linear interferometry
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作者 Wenting Wang Wenzheng Liu +15 位作者 Hao Liu Tristan Melton Alwaleed Aldhafeeri Dong-Il Lee Jinghui Yang Abhinav Kumar Vinod Jinkang Lim Yoon-Soo Jang Heng Zhou Mingbin Yu Patrick Guo-Qiang Lo Dim-Lee Kwong Peter DeVore Jason Chou Ninghua Zhu Chee Wei Wong 《Advanced Photonics Nexus》 2025年第3期120-130,共11页
Laser frequency microcombs provide a series of equidistant,coherent frequency markers across a broad spectrum,enabling advancements in laser spectroscopy,dense optical communications,precision distance metrology,and a... Laser frequency microcombs provide a series of equidistant,coherent frequency markers across a broad spectrum,enabling advancements in laser spectroscopy,dense optical communications,precision distance metrology,and astronomy.Here,we design and fabricate silicon nitride,dispersion-managed microresonators that effectively suppress avoided-mode crossings and achieve close-to-zero averaged dispersion.Both the stochastic noise and mode-locking dynamics of the resonator are numerically and experimentally investigated.First,we experimentally demonstrate thermally stabilized microcomb formation in the microresonator across different mode-locked states,showing negligible center frequency shifts and a broad frequency bandwidth.Next,we characterize the femtosecond timing jitter of the microcombs,supported by precise metrology of the timing phase and relative intensity noise.For the single-soliton state,we report a relative intensity noise of−153.2 dB∕Hz,close to the shot-noise limit,and a quantum-noise–limited timing jitter power spectral density of 0.4 as 2∕Hz at a 100 kHz offset frequency,measured using a self-heterodyne linear interferometer.In addition,we achieve an integrated timing jitter of 1.7 fs±0.07 fs,measured from 10 kHz to 1 MHz.Measuring and understanding these fundamental noise parameters in high clock rate frequency microcombs is critical for advancing soliton physics and enabling new applications in precision metrology. 展开更多
关键词 frequency microcomb timing jitter self-heterodyne linear interferometry dispersion-managed microresonator
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Measuring Nanoscale Interface Thermal Resistance via Electron Microscope
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作者 Fa-Chen Liu Peng Gao 《Chinese Physics Letters》 2025年第8期285-304,共20页
Rapid technological advancements drive miniaturization and high energy density in devices,thereby increasing nanoscale thermal management demands and urging development of higher spatial resolution technologies for th... Rapid technological advancements drive miniaturization and high energy density in devices,thereby increasing nanoscale thermal management demands and urging development of higher spatial resolution technologies for thermal imaging and transport research.Here,we introduce an approach to measure nanoscale thermal resistance using in situ inelastic scanning transmission electron microscopy.By constructing unidirectional heating flux with controlled temperature gradients and analyzing electron energy-loss/gain signals under optimized acquisition conditions,nanometer-resolution in mapping phonon apparent temperature is achieved.Thus,interfacial thermal resistance is determined by calculating the ratio of interfacial temperature difference to bulk temperature gradient.This methodology enables direct measurement of thermal transport properties for atomic-scale structural features(e.g.,defects and heterointerfaces),resolving critical structure-performance relationships,providing a useful tool for investigating thermal phenomena at the(sub-)nanoscale. 展开更多
关键词 measure nanoscale thermal resistance nanoscale thermal resistance technological advancements higher spatial resolution technologies situ inelastic scanning transmission electron microscopyby constructing unidirectional heating flux controlled temperature gradients transport researchherewe thermal imaging
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Electron Microscopy and Spectroscopy Investigation of Atomic, Electronic, and Phonon Structures of NdNiO_(2)/SrTiO_(3) Interface
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作者 Yuan Yin Mei Wu +9 位作者 Xiang Ding Peiyi He Qize Li Xiaowen Zhang Ruixue Zhu Ruilin Mao Xiaoyue Gao Ruochen Shi Liang Qiao Peng Gao 《Chinese Physics Letters》 2025年第4期130-141,共12页
The infinite-layer nickelates,proposed as analogs to superconducting cuprates,provide a promising platform for exploring the mechanisms of unconventional superconductivity.However,the superconductivity has been exclus... The infinite-layer nickelates,proposed as analogs to superconducting cuprates,provide a promising platform for exploring the mechanisms of unconventional superconductivity.However,the superconductivity has been exclusively observed in thin films under atmospheric pressure,underscoring the critical role of the heterointerface. 展开更多
关键词 atomic structure phonon structure electron microscopy electronic structure SPECTROSCOPY NdNiO SrTiO interface thin films superconducting cupratesprovide
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Electromagnetically-induced-absorption-like ground state cooling in a hybrid optomechanical system
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作者 Yaoyong Dong Xuejun Zheng +1 位作者 Denglong Wang Peng Zhao 《Chinese Physics B》 2025年第4期413-421,共9页
We present a scheme for the electromagnetically-induced-absorption(EIA)-like ground state cooling in a hybrid optomechanical system which is combined by two-level quantum systems(qubits)and a high-Q optomechanical cav... We present a scheme for the electromagnetically-induced-absorption(EIA)-like ground state cooling in a hybrid optomechanical system which is combined by two-level quantum systems(qubits)and a high-Q optomechanical cavity.Under the weak qubit-cavity coupling,the system exhibits an EIA-like effect and this effect is caused by quantum destructive interference that is distinct from the conventional EIA effect driven by quantum constructive interference.More importantly,the EIA-like cooling mechanism can significantly enhance the cooling rate of the hybrid system,enabling the final phonon number beyond the classical cooling limit in the strong optomechanical coupling regime.Meanwhile,the cooling effects of the EIA case is better than that of the normalmode splitting case under the same optomechanical coupling strength and qubit dissipation rate. 展开更多
关键词 electromagnetically induced absorption ground state cooling OPTOMECHANICS
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Design and start-to-end beam dynamics simulation of the first super-radiant THz free-electron laser source in Thailand
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作者 Natthawut Chaisueb Sakhorn Rimjaem 《Nuclear Science and Techniques》 2025年第7期222-235,共14页
A super-radiant terahertz free-electron laser(THz-FEL)light source was developed for the first time in Thailand and Southeast Asia at the PBP-CMU Electron Linac Laboratory(PCELL)of Chiang Mai University.This radiation... A super-radiant terahertz free-electron laser(THz-FEL)light source was developed for the first time in Thailand and Southeast Asia at the PBP-CMU Electron Linac Laboratory(PCELL)of Chiang Mai University.This radiation source requires relatively ultrashort electron bunches to produce intense coherent THz pulses.Three electron bunch compression processes are utilized in the PCELL accelerator system comprising pre-bunch compression in an alpha magnet,velocity bunching in a radio-frequency(RF)linear accelerator(linac),and magnetic bunch compression in a 180°acromat system.Electron bunch compression in the magnetic compressor system poses considerable challenges,which are addressed through the use of three quadrupole doublets.The strengths of the quadrupole fields significantly influence the rotation of the beam line longitudinal phase space distribution along the bunch compressor.Start-to-end beam dynamics simulations using the ASTRA code were performed to optimize the electron beam properties for generating super-radiant THz-FEL radiation.The operational parameters considered in the simulations comprise the alpha magnet gradient,linac RF phase,and quadrupole field strengths.The optimization results show that 10-16MeV femtosecond electron bunches with a low energy spread(~0.2%),small normalized emittance(~15πmm·mrad),and high peak current(165-247A)can be produced by the PCELL accelerator system at the optimal parameters.A THz-FEL with sub-microjoule pulse energies can thus be obtained at the optimized electron beam parameters.The physical and conceptual design of the THz-FEL beamline were completed based on the beam dynamics simulation results.The construction and installation of this beamline are currently underway and expected to be completed by mid-2024.The commissioning of the beamline will then commence. 展开更多
关键词 THz radiation THz free-electron laser Super-radiant free-electron laser Pre-bunched free-electron laser Beam dynamic simulation Femtosecond electron bunches
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Magneto Thermosolutal-Aiding Free Convection in a Nanofluid-Filled-Non-Darcy Porous Annulus under Local Thermal Non-Equilibrium Approach
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作者 Abdelhakim Lahrech Tahar Tayebi +2 位作者 Mohamed Kallel Mehdi Hashemi-Tilehnoee Ali J.Chamkha 《Computer Modeling in Engineering & Sciences》 2025年第7期359-385,共27页
The study considers numerical findings regarding magneto-thermosolutal-aided natural convective flow of alumina/water-based nanofluid filled in a non-Darcian porous horizontal concentric annulus.Two equations are assu... The study considers numerical findings regarding magneto-thermosolutal-aided natural convective flow of alumina/water-based nanofluid filled in a non-Darcian porous horizontal concentric annulus.Two equations are assumed to evaluate the thermal fields in the porous medium under Local Thermal Non-Equilibrium(LTNE)conditions,along with the Darcy-Brinkman-Forchheimer model for the flow.By imposing distinct and constant temperatures and concentrations on both internal and external cylinders,thermosolutal natural convection is induced in the annulus.We apply the finite volume method to solve the dimensionless governing equations numerically.The thermal conductivity and viscosity of the nanofluid mixture are determined utilizing Corcione’s empirical correlations,incorporating the effects of Brownian diffusion of nanoparticles.Steady-state findings are provided for a range of significant parameters,including buoyancy ratio(N=1 to 5),Lewis(Le=0 to 10),Rayleigh(Ra=102 to 105),Hartmann(Ha=0 to 50),and heat generation in the nanofluid and solid phases(Q=0 to 20)when the nanofluid flow is driven by aiding thermal and mass buoyancies at given porous medium characteristics(porosity(ε),Darcy number(Da),porous interfacial heat transfer coefficient(H),and thermal conductivity ratio(γ),to assess the thermosolutal convective circulation beside heat and solutal transfer rates in the annulus.The results reveal that internal heat generation significantly modifies the heat transport mechanism,initially reducing and then enhancing heat transfer rates as Q increases.Interestingly,increasing Le reduces heat transfer at low Q but promotes it when Q>5,while mass transfer consistently increases with Le.The magnetic field represses heat transfer in the absence of internal heat but enhances it when internal heat is present. 展开更多
关键词 Magnetized thermosolutal convection porous interfacial heat transfer coefficient porous annulus LTNE two-energy equations model heat generating
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Single-Dislocation Phonons:Atomic-Scale Measurement and Their Thermal Properties
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作者 Yue-Hui Li Bo Han +12 位作者 Xiao-Long Yang Rui-Lin Mao Fa-Chen Liu Ruo-Chen Shi Rui-Shi Qi Xiao-Rui Hao Ning Li Bing-Yao Liu Xiao-Mei Li Jin-Long Du Ji Chen Wu Li Peng Gao 《Chinese Physics Letters》 2025年第6期110-139,共30页
Nanoscale defects such as dislocations have a significant impact on the phonon thermal transport properties in non-metallic materials.To unravel these effects,an understanding of defect phonon modes is essential.Herei... Nanoscale defects such as dislocations have a significant impact on the phonon thermal transport properties in non-metallic materials.To unravel these effects,an understanding of defect phonon modes is essential.Herein,at the atomic scale,the localized phonons of individual dislocations at a Si/Ge interface are measured via monochromated electron energy loss spectroscopy in a scanning transmission electron microscope.These modes are then correlated with the local microstructure,further revealing the dislocation effects on the local thermal transport properties.The dislocation causes a phonon redshift of several milli-electron-volts within about two to four nanometers of the core,where both the strain field and Ge segregation play roles.With the presence of dislocation,the local interfacial thermal conductance can be either enhanced or reduced,depending on the complex interaction and competition between lattice disorder(dislocation)and element disorder(heterointerface mixing and Ge-segregation)at the interface.These findings provide valuable insights to improve the thermal properties of thermoelectric generators and thermal management systems through proper defect engineering. 展开更多
关键词 localized phonons defect phonon modes scanning transmission electron microscopethese single dislocation phonons phonon thermal transport properties thermal transport properties monochromated electron energy loss spectroscopy scanning transmission electron microscope
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Design and optimization of generation and transportation systems for coherent THz transition radiation in spectroscopic applications
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作者 Siriwan Pakluea Kanlayaporn Kongmali +3 位作者 Monchai Jitvisate Jatuporn Saisut Chitrlada Thongbai Sakhorn Rimjaem 《Nuclear Science and Techniques》 2025年第8期34-48,共15页
Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has... Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has focused on developing or improving THz sources,detectors,and applications.At the PBP-CMU Electron Linac Laboratory(PCELL)of the Plasma and Beam Physics Research Facility in Chiang Mai University,high-intensity THz radiation has been generated in the form of coherent transition radiation(TR)and investigated since 2006 for electron beams with energies ranging from 8 to 12 MeV.In this study,we investigate and optimize the coherent TR arising from short electron bunches with energies ranging from 8 to 22 MeV using an upgraded linear-accelerator system with a higher radio-frequency(RF)power system.This radiation is then transported from the accelerator hall to the experimental room,in which the spectrometers are located.Electron-beam simulations are conducted to achieve short bunch lengths and small transverse beam sizes at the TR station.Radiation properties,including the radiation spectrum,angular distribution,and radiation polarization,are thoroughly investigated.The electron-bunch length is evaluated using the measuring system.The radiation-transport line is designed to achieve optimal frequency response and high transmission efficiency.A radiation-transmission efficiency of approximately 80-90%can be achieved with this designed system,along with a pulse energy ranging from 0.17 to 0.25μJ.The expected radiation spectral range covers up to 2 THz with a peak power of 0.5-1.25 MW.This coherent,broadband,and intense THz radiation will serve as a light source for THz spectroscopy and THz time-domain spectroscopy applications at the PCELL in the near future. 展开更多
关键词 THz radiation Transition radiation Radiation transportation
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Using multi-scale interaction mechanisms in yolk-shell structured C/Co composite materials for electromagnetic wave absorption
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作者 Jintang Zhou Kexin Zou +11 位作者 Jiaqi Tao Jun Liu Yijie Liu Lvtong Duan Zhenyu Cheng Borui Zha Zhengjun Yao Guiyu Peng Xuewei Tao Hexia Huang Yao Ma Peijiang Liu 《Journal of Materials Science & Technology》 2025年第12期36-44,共9页
Advanced chemical engineering for simultaneous modulation of nanomaterial morphology, defects, interfaces, and structure to enhance electromagnetic and microwave absorption (MA) performance. However, accurately distin... Advanced chemical engineering for simultaneous modulation of nanomaterial morphology, defects, interfaces, and structure to enhance electromagnetic and microwave absorption (MA) performance. However, accurately distinguishing the MA contributions of different scale factors and tuning the optimal combined effects remains a formidable challenge. This study employs a synergistic approach combining template protection etching and vacuum annealing to construct a controlled system of micrometer-sized cavities and amorphous carbon matrices in metal-organic framework (MOF) derivatives. The results demonstrate that the spatial effects introduced by the hollow structure enhance dielectric loss but significantly weaken impedance matching. By increasing the proportion of amorphous carbon, the balance between electromagnetic loss and impedance matching can be effectively maintained. Importantly, in a suitable graphitization environment, the presence of oxygen vacancies in amorphous carbon can induce significant polarization to compensate for the reduced conductivity loss due to the absence of sp2 carbon. Through the synergistic effects of morphology and composition, the samples exhibit a broader absorption bandwidth (6.28 GHz) and stronger reflection loss (−61.64 dB) compared to the original MOF. In conclusion, this study aims to elucidate the multiscale impacts of macroscopic micro-nano structure and microscopic defect engineering, providing valuable insights for future research in this field. 展开更多
关键词 MOFS Multi-scale regulation Yolk-shell structure Amorphous carbon Oxygen vacancy Microwave absorption
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Fabrication of Tb/Eu co-doped borosilicate glasses for white-light LED and broadband photodetection
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作者 Hong Jia Yingying Wang +9 位作者 Yi Long Xuying Niu Hui Zhou Jie Yang Yuquan Yuan Yanfei Hu Xiaoyun Xu Xiaofeng Liu Feng Peng Zaijin Fang 《Journal of Rare Earths》 2025年第7期1355-1363,共9页
We successfully prepared a series of rare-earth doped borosilicate glasses using the melt-quenching method,and carefully investigated the luminescent properties and the spectral modulation of Tb/Eucodoped borosilicate... We successfully prepared a series of rare-earth doped borosilicate glasses using the melt-quenching method,and carefully investigated the luminescent properties and the spectral modulation of Tb/Eucodoped borosilicate glasses under UV(200-400 nm)excitation.The results show that the prepared samples have the characteristics of broadband response,excellent transparency and tunable luminescence.By adjusting the excitation wavelength,the emissions of Tb^(3+),Eu^(2+)and Eu^(3+)ions are observed,which exhibit yellow-green,blue,red color and multi-color even white emissions,respectively.Moreover,the energy transfer between Tb^(3+)and Eu^(3+)ions in the codoped glasses is confirmed.Tb^(3+)absorbs a large number of solar-blind light,transfers to Eu^(3+)and results in intense visible emission in a wide waveband range.This makes the Tb/Eu co-doped glass a desirable candidate for solar-blind light detections.The photodetection system was built and shows a strong and stable response to the UV light of 210-400 nm.Due to broad detection range,high sensitivity and stability,our results offer strong implications for the development of photodetection device for diverse applications. 展开更多
关键词 Rare earth ions Tb/Eu co-doped Borosilicate glass PHOTODETECTORS
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Moderate Fields, Maximum Potential: Achieving High Records with Temperature‑Stable Energy Storage in Lead‑Free BNT‑Based Ceramics 被引量:1
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作者 Wenjing Shi Leiyang Zhang +7 位作者 Ruiyi Jing Yunyao Huang Fukang Chen Vladimir Shur Xiaoyong Wei Gang Liu Hongliang Du Li Jin 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期184-200,共17页
The increasing awareness of environmental concerns has prompted a surge in the exploration of leadfree,high-power ceramic capacitors.Ongoing efforts to develop leadfree dielectric ceramics with exceptional energystora... The increasing awareness of environmental concerns has prompted a surge in the exploration of leadfree,high-power ceramic capacitors.Ongoing efforts to develop leadfree dielectric ceramics with exceptional energystorage performance(ESP)have predominantly relied on multicomponent composite strategies,often accomplished under ultrahigh electric fields.However,this approach poses challenges in insulation and system downsizing due to the necessary working voltage under such conditions.Despite extensive study,bulk ceramics of(Bi_(0.5)Na_(0.5))TiO_(3)(BNT),a prominent lead-free dielectric ceramic family,have seldom achieved a recoverable energy-storage(ES)density(Wrec)exceeding 7 J cm^(−3).This study introduces a novel approach to attain ceramic capacitors with high ESP under moderate electric fields by regulating permittivity based on a linear dielectric model,enhancing insulation quality,and engineering domain structures through chemical formula optimization.The incorporation of SrTiO_(3)(ST)into the BNT matrix is revealed to reduce the dielectric constant,while the addition of Bi(Mg_(2/3)Nb_(1/3))O_(3)(BMN)aids in maintaining polarization.Additionally,the study elucidates the methodology to achieve high ESP at moderate electric fields ranging from 300 to 500 kV cm^(−1).In our optimized composition,0.5(Bi_(0.5)Na_(0.4)K_(0.1))TiO_(3)–0.5(2/3ST-1/3BMN)(B-0.5SB)ceramics,we achieved a Wrec of 7.19 J cm^(−3) with an efficiency of 93.8%at 460 kV cm^(−1).Impressively,the B-0.5SB ceramics exhibit remarkable thermal stability between 30 and 140℃ under 365 kV cm^(−1),maintaining a Wrec exceeding 5 J cm^(−3).This study not only establishes the B-0.5SB ceramics as promising candidates for ES materials but also demonstrates the feasibility of optimizing ESP by modifying the dielectric constant under specific electric field conditions.Simultaneously,it provides valuable insights for the future design of ceramic capacitors with high ESP under constraints of limited electric field. 展开更多
关键词 BNT Energy storage LEAD-FREE Relaxor ferroelectrics Capacitors
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Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials
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作者 Rui Zhao Jian Zheng +4 位作者 Jin Guo Yunbo Shi Hengzhen Feng Jun Tang Jun Liu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期217-224,共8页
In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation pr... In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped lattices.The effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and analyzed.The target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent lattices.The proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k Hz.After the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target frequency.These results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment. 展开更多
关键词 Star-shaped metamaterials BROADBAND Vibration attenuation Low-frequency ultrasound vibration Transmission loss
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Benzothiadiazole-based materials for organic solar cells
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作者 Qiang Bei Bei Zhang +3 位作者 Kaifeng Wang Shiming Zhang Guichuan Xing Clément Cabanetos 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期3-15,共13页
The past few years have witnessed power conversion efficiency(PCE)of organic solar cells(OSCs)skyrocketing to the value of 20%due to the outstanding advantages of organic photoactive materials.The latter,which consist... The past few years have witnessed power conversion efficiency(PCE)of organic solar cells(OSCs)skyrocketing to the value of 20%due to the outstanding advantages of organic photoactive materials.The latter,which consist of donor and acceptor materials,indeed play important roles in OSCs,and particularly one building block has attracted considerable research attention,namely benzothiadiazole(BT).The diversity of OSCs based on the BT structure have indeed sprung up,and the progressive increase in PCE values is more than just eye-catching since it heralds a renewal and bright future of OSCs.This review analyzes significant studies that have led to these remarkable progresses and focuses on the most effective BT small-molecules and BT polymers for OSC reported in the last decades.The pivotal structure-property relationships,donor-acceptor matching criteria,and morphology control approaches are gathered and discussed in this paper.Lastly,we summarize the remaining challenges and offer a personal perspective on the future advance and improvement of OSCs. 展开更多
关键词 Organic solar cells BENZOTHIADIAZOLE DONOR ACCEPTOR POLYMER Non-fullerene acceptors
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Improving the operational stability of perovskite solar cells with cesium-doped graphene oxide interlayer
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作者 Masaud Almalki Katerina Anagnostou +15 位作者 Konstantinos Rogdakis Felix T.Eickemeyer Mostafa Othman Minas M.Stylianakis Dimitris Tsikritzis Anwar Q.Alanazi Nikolaos Tzoganakis Lukas Pfeifer Rita Therisod Xiaoliang Mo Christian M.Wolff Aïcha Hessler-Wyser Shaik M.Zakeeruddin Hong Zhang Emmanuel Kymakis Michael Grätzel 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期483-490,共8页
Perovskite solar cells(PSCs)have made great advances in terms of power conversion efficiency(PCE),yet their subpar stability continues to hinder their commercialization.The interface between the perovskite layer and t... Perovskite solar cells(PSCs)have made great advances in terms of power conversion efficiency(PCE),yet their subpar stability continues to hinder their commercialization.The interface between the perovskite layer and the charge-carrier transporting layers plays a crucial role in undermining the stability of PSCs.In this work,we propose a strategy to stabilize high-performance PSCs with PCE over 23%by introducing a cesium-doped graphene oxide(GO-Cs)as an interlayer between the perovskite and hole-transporting material.The GO-Cs treated PSCs exhibit excellent operational stability with a projected T80(the time where the device PCE reduces to 80%of its initial value)of 2143 h of operation at the maximum powering point under one sun illumination. 展开更多
关键词 Perovskite solar cells Doped graphene oxide Graphene related material Long-term operational stability
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