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Microstructure and Properties of Mg/Fe Dissimilar Metal Joints Fabricated by Magnetic Pulse Welding
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作者 Xie Jilin Li Shimeng +3 位作者 Wang Yaping Liu Dongya Liu Xiaofang Chen Yuhua 《稀有金属材料与工程》 北大核心 2026年第1期67-77,共11页
Dissimilar AZ31B magnesium alloy and DC56D steel were welded via AA1060 aluminum alloy by magnetic pulse welding.The effects of primary and secondary welding processes on the welded interface were comparatively invest... Dissimilar AZ31B magnesium alloy and DC56D steel were welded via AA1060 aluminum alloy by magnetic pulse welding.The effects of primary and secondary welding processes on the welded interface were comparatively investigated.Macroscopic morphology,microstructure,and interfacial structure of the joints were analyzed using scanning electron microscope,energy dispersive spectrometer,and X-ray diffractometer(XRD).The results show that magnetic pulse welding of dissimilar Mg/Fe metals is achieved using an Al interlayer,which acts as a bridge for deformation and diffusion.Specifically,the AZ31B/AA1060 interface exhibits a typical wavy morphology,and a transition zone exists at the joint interface,which may result in an extremely complex microstructure.The microstructure of this transition zone differs from that of AZ31B magnesium and 1060 Al alloys,and it is identified as brittle intermetallic compounds(IMCs)Al_(3)Mg_(2) and Al_(12)Mg_(17).The transition zone is mainly distributed on the Al side,with the maximum thickness of Al-side transition layer reaching approximately 13.53μm.Incomplete melting layers with varying thicknesses are observed at the primary weld interface,while micron-sized hole defects appear in the transition zone of the secondary weld interface.The AA1060/DC56D interface is mainly straight,with only a small number of discontinuous transition zones distributed intermittently along the interface.These transition zones are characterized by the presence of the brittle IMC FeAl_(3),with a maximum thickness of about 4μm. 展开更多
关键词 magnetic pulse welding mechanical properties MICROSTRUCTURE fracture morphology primary and secondary welding
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Low-Density Pulsed Current Induced Refinement of Secondary α Phase for Strengthening Ti-6Al-4V-0.5Mo-0.5Zr Alloy Without Sacrificing Ductility
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作者 Tu Yanni Luo Wei +2 位作者 Liu Huiqun Feng Weizhong Zhang Pinghui 《稀有金属材料与工程》 北大核心 2026年第1期78-91,共14页
Low-density short-duration pulsed current-assisted aging treatment was applied to the Ti-6Al-4V-0.5Mo-0.5Zr alloy subjected to different solution treatments.The results show that numerous α_(p) phases redissolve into... Low-density short-duration pulsed current-assisted aging treatment was applied to the Ti-6Al-4V-0.5Mo-0.5Zr alloy subjected to different solution treatments.The results show that numerous α_(p) phases redissolve into the new β phase during the pulsed current-assisted aging process,and then the newly formed β phase is mainly transformed into the β_(t) phase,with occasional transition to new α_(p) phase,leading to a remarkable grain refinement,especially for the lamellarαs phases.In comparison to conventional aging treatment,the pulsed current-assisted aging approach achieves a significant enhancement in strength without degrading ductility,yielding an excellent mechanical property combination:a yield strength of 932 MPa,a tensile strength of 1042 MPa,and an elongation of 12.2%.It is primarily ascribed to the increased fraction of β_(t) phases,the obvious grain refinement effect,and the slip block effect induced by the multiple-variantαs colonies distributed within β_(t) phases. 展开更多
关键词 titanium alloy pulsed current microstructure refinement strength DUCTILITY
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Novel pulse electrolysis anti-biofouling technology for front-end filter of water-cooled system on offshore largescale wind power platform
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作者 Xile WEI Liheng WANG +4 位作者 Yi WANG Xiaowen ZHOU Jingyi ZHANG Xiaodong WANG Yingjie CHEN 《Journal of Oceanology and Limnology》 2026年第1期150-159,共10页
Water-cooled system have significantly enhanced the power generation efficiency of offshore wind turbines.However,these innovative systems are susceptible to substantial biological fouling,maintenance challenges,and h... Water-cooled system have significantly enhanced the power generation efficiency of offshore wind turbines.However,these innovative systems are susceptible to substantial biological fouling,maintenance challenges,and high upkeep costs.Therefore,the development of a specialized front-end filter tailored for direct current water-cooled system is importance.This involves the integration of dimensionally stable anode(DSA)and nickel alloy cathode,valued for their corrosion resistance in seawater,into a novel front-end filter system for Water-cooled applications.This system has the dual capability of generating hydrogen and chlorine for self-cleaning purposes.Implementing a flushing pulse electrolysis mode,it effectively mitigates electrode failure induced by cathodic calcium and magnesium deposition,thereby significantly prolonging electrode lifespan.Laboratory tests comprising system assembly and performance evaluations were conducted,with the system programmed to operate for 5 minutes every 24 hours under continuous flushing by natural seawater to simulate real-world conditions.After more than 11 months of continuous flushing,observations reveal that the DSA mesh and nickel alloy mesh maintain intact structural integrity and normal functioning.Subsequent 1꞉1 physical prototype Sea trial further validated the soundness of the system design and electrolytic control parameters. 展开更多
关键词 water-cooled system pulse electrolysis ANTIFOULING dimensionally stable anode(DSA) nickel alloy offshore wind turbine
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SNMR with short pulses:Optimizing the kernel calculation by considering the influence of pulse shape and phase
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作者 Tobias Splith Thomas Hiller +1 位作者 Stephan Costabel Mike Müller-Petke 《Magnetic Resonance Letters》 2026年第1期43-52,共10页
In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially satura... In the past few years,efforts have been made to extend the sensitivity of surface nuclear magnetic resonance(SNMR)to short relaxation times,typical for strongly bound water,which,for example,occurs in partially saturated soils.The two limiting factors for the sensitivity are the dead time after the excitation pulse and the duration of the pulse itself.To enable short pulses,while also achieving proper depths of investigation,high pulse amplitudes are needed.This makes it necessary to consider the Bloch-Siegert effect,i.e.the counter-rotating component and the parallel component of the excitation field have significant influence on the excitation.If an untuned transmitter circuit is used,the pulse shape will also be non-sinusoidal.In this paper,we demonstrate that this influences SNMR measurements with short pulses in two ways:On one hand,the pulse shape influences the phase of the fundamental frequency oscillation.On the other,at very high pulse amplitudes,other frequency components of the excitation field start to influence the excitation.The behavior of the macroscopic magnetizations in the subsurface during the pulse is simulated by solving the Bloch equations,using the pulse shape as an input.Since these calculations are computational expensive,we propose a lookup scheme that allows a time efficient modeling of the obtained SNMR data. 展开更多
关键词 Surface NMR pulse shape Numerical modeling Bloch-Siegert effect
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Numerical Investigation of CO_(2)Contaminant Transport and Deposition in an In-Line Pulse Tube Cryocooler
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作者 Hao Zhu Xi Chen +3 位作者 Pengcheng Qu Yifan Zhu Haoyi Wang Yingxia Qi 《Frontiers in Heat and Mass Transfer》 2026年第1期54-71,共18页
Pulse tube cryocoolers are widely employed in cryogenic systems,where gas contamination has become a critical factor limiting both performance and service life.To further investigate the condensation behavior of conta... Pulse tube cryocoolers are widely employed in cryogenic systems,where gas contamination has become a critical factor limiting both performance and service life.To further investigate the condensation behavior of contaminants,this study develops a two-dimensional axisymmetric model of a linear-type cryocooler to simulate the transport and deposition processes of trace CO_(2),evaluating the impact of contamination on system pressure drop under various operating conditions.Results indicate that CO_(2)diffusion is primarily driven by concentration gradients.The CO_(2)deposition rate increases markedly at low temperatures and high concentrations,with over 90%of deposition occurring in the cold-end heat exchanger.Under different concentration distributions,dry ice predominantly accumulates in the cold-end heat exchanger;however,notable differences emerge in the pulse tube.In the uniform distribution case,CO_(2)tends to deposit along the inner wall of the pulse tube,whereas in the gradual release scenario,deposition mainly occurs on the cold-end flow straightening mesh screen.Dry ice deposition significantly increases the pressure drop across the system and decreases the pressure wave amplitude,resulting in a degradation of cooling capacity.This study lays a foundation for further investigation into the thermal properties of contaminant layers and provides theoretical guidance for optimizing cold-end components to improve contamination resilience. 展开更多
关键词 pulse tube cryocoolers carbon dioxide dry ice deposition CFD
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Characterization of the susceptibility of ore particles to breakdown in high voltage pulse breakage and the influencing factors
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作者 Rui Sun Yang Hong +5 位作者 Daqian Wang Liang Si Jianguo Yang Wei Huang Liefeng Huang Weiran Zuo 《International Journal of Mining Science and Technology》 2026年第1期113-124,共12页
The susceptibility of ore particles to electrical breakdown plays a critical role for high voltage pulse(HVP)breakage,yet its quantitative characterization still lacks deep understanding.Two indicators,namely breakdow... The susceptibility of ore particles to electrical breakdown plays a critical role for high voltage pulse(HVP)breakage,yet its quantitative characterization still lacks deep understanding.Two indicators,namely breakdown delay time(T_(d))and breakdown strength(E_(b))were compared,based on analysis on the two breakdown modes namely wavefront mode and post-wave mode.It was found that T_(d) is more suitable to characterize the susceptibility of ore particles to electrical breakdown in HVP breakage than E_(b).A probabilistic model based on the Weibull distribution is developed to describe the relation of breakdown probability to T_(d).Regression analyses were conducted to investigate how operating parameters and particle properties influence Td and size reduction degree of ore particles in HVP breakage.The regressed models demonstrate potential capability to predict metallic minerals content and HVP breakage degree based on operating parameters and particle properties. 展开更多
关键词 Electrical breakdown High voltage pulse breakage SUSCEPTIBILITY Breakdown delay time
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Magnetic pulse welding of Al-5754 with Al-7075 and MARS 380:Weldability windows and ballistic testing
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作者 Benoit Lagain Thomas Heuzé +1 位作者 Guillaume Racineux Michel Arrigoni 《Defence Technology(防务技术)》 2026年第1期64-79,共16页
Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible.Magnetic Pulse Welding(MPW)offers a solidstate joining... Joining dissimilar materials encounters significant engineering challenges due to the contrast in material properties that makes conventional welding not feasible.Magnetic Pulse Welding(MPW)offers a solidstate joining technique that overcomes these issues by using impact to create strong bonds without melting the substrate materials.This study investigates the weldability of aluminum alloy Al-5754 with Al-7075 and MARS 380 steel,used in armouring solutions of defense systems,by the use of MPW.In this work,weldability windows are investigated by varying standoff distances between the coating material and its substrate(0.25-4.5 mm)and discharge energies(5-13 kJ)with both O-shape and U-shape inductors.Mechanical strength of the welded joints were assessed through single lap shear tests,identifying optimal welding parameters.Then,the velocity profiles of the flyer plates were measured using heterodyne velocimetry to understand the dynamics of the impact.Then,substructures assembled with the optimal welding conditions were subjected to ballistic testing using 7.62 mm×51 mm NATO and 9 mm×19 mm Parabellum munitions to evaluate the resilience of the welds under ballistic impact.The outcomes demonstrate that MPW effectively joins Al-5754 with both Al-7075 and MARS 380,producing robust welds capable of withstanding ballistic impacts under certain conditions.This research advances the application of MPW in lightweight ballistic protection of defense systems,contributing to the development of more resilient and lighter protective structures. 展开更多
关键词 Magnetic pulse welding(MPW) Dissimilar material joining Weldability windows Impact welding Ballistic testing
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A high-accuracy particle-type labeling method for organic scintillator pulse waveform datasets
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作者 Lin-Jun Hou Peng Xu +1 位作者 Zhi-Meng Hu Jie Cheng 《Nuclear Science and Techniques》 2026年第2期143-155,共13页
The pulse shape discrimination technique plays a pivotal role in neutron field measurements using organic scintillator detectors,and the particle-type labeling accuracy of the pulse waveform dataset has a significant ... The pulse shape discrimination technique plays a pivotal role in neutron field measurements using organic scintillator detectors,and the particle-type labeling accuracy of the pulse waveform dataset has a significant impact on its performance,especially with the growing use of machine learning methods.In this study,a high-accuracy labeling method for pulse waveform datasets based on the time-of-flight(TOF)filtering method,an improved charge comparison method(CCM),and the coincidence measurement method is proposed.The relationship between the experimental parameters and the chance coincidence proportion in the TOF measurement was derived to reduce contamination from chance coincidences at the experimental level.Based on this,an experiment was conducted to obtain raw data using the^(241)AmBe source,and a piled-up identification algorithm based on reference waveform cross-correlation and differential analysis was designed to filter out piled-up pulses.To improve the labeling accuracy,the CCM was optimized,a simple method of selecting the TOF interval for a lower chance coincidence proportion was proposed,and a low-amplitude pulse waveform dataset construction method based on coincidence measurements was developed.To verify these methods,eight pulse waveform datasets were constructed using different combinations of the proposed approaches.Three neural network structures and a corresponding evaluation parameter were designed to test the quality of these datasets.The results showed that the particle identification performance of the CCM was significantly improved after optimization,with the neutron-to-gamma-ray misidentification rate reduced by more than 35%.The proposed accuracy improvement methods reduced ambiguous identification results from these artificial neural networks by more than 50%. 展开更多
关键词 pulse shape discrimination Organic liquid scintillator Time of flight Charge comparison method Machine learning
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Demonstration of full-scale spatiotemporal diagnostics of solid-density plasmas driven by an ultra-short relativistic laser pulse using an X-ray free-electron laser
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作者 Lingen Huang Michal Smíd +42 位作者 Long Yang Oliver Humphries Johannes Hagemann Thea Engler Xiayun Pan Yangzhe Cui Thomas Kluge Ritz Aguilar Carsten Baehtz Erik Brambrink Engin Eren Katerina Falk Alejandro Laso Garcia Sebastian Gode Christian Gutt Mohamed Hassan Philipp Heuser Hauke Hoppner Michaela Kozlova Wei Lu Josefine Metzkes-Ng Masruri Masruri Mikhail Mishchenko Motoaki Nakatsutsumi Masato Ota Ozgül Oztürk Alexander Pelka Irene Prencipe Thomas R.Preston Lisa Randolph Martin Rehwald Hans-Peter Schlenvoigt Ulrich Schramm Jan-Patrick Schwinkendorf Sebastian Starke Radka Stefaníková Erik Thiessenhusen Monika Toncian Toma Toncian Jan Vorberger Ulf Zastrau Karl Zeil Thomas E.Cowan 《Matter and Radiation at Extremes》 2026年第1期6-19,共14页
Understanding the complex plasma dynamics in ultra-intense relativistic laser-solid interactions is of fundamental importance for applications of laser-plasma-based particle accelerators,the creation of high-energy-de... Understanding the complex plasma dynamics in ultra-intense relativistic laser-solid interactions is of fundamental importance for applications of laser-plasma-based particle accelerators,the creation of high-energy-density matter,understanding planetary science,and laser-driven fusion energy.However,experimental efforts in this regime have been limited by the lack of accessibility of over-critical densities and the poor spatiotemporal resolution of conventional diagnostics.Over the last decade,the advent of femtosecond brilliant hard X-ray free-electron lasers(XFELs)has opened new horizons to overcome these limitations.Here,for the first time,we present full-scale spatiotemporal measurements of solid-density plasma dynamics,including preplasma generation with tens of nanometer scale length driven by the leading edge of a relativistic laser pulse,ultrafast heating and ionization at the main pulse arrival,the laser-driven blast wave,and transient surface return current-induced compression dynamics up to hundreds of picoseconds after interaction.These observations are enabled by utilizing a novel combination of advanced X-ray diagnostics including small-angle X-ray scattering,resonant X-ray emission spectroscopy,and propagation-based X-ray phase-contrast imaging simultaneously at the European XFEL-HED beamline station. 展开更多
关键词 preplasma generation spatiotemporal diagnostics understanding complex plasma dynamics x ray free electron laser planetary scienceand conventional diagnosticsover solid density plasmas ultra short relativistic laser pulse
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Irradiation of granite surface by nanosecond pulsed laser:Optimal softening parameters and properties
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作者 LI Zi-kun ZHANG Xue-min +5 位作者 CHEN Jing OU Xue-feng ZHOU Xian-shun WU Chao-guang TANG Ke-lin ZHU Wen-yang 《Journal of Central South University》 2026年第1期317-334,共18页
Irradiating hard rocks by a high-power laser can reduce localized hardness in the rocks;however,continuous lasers produce a large amount of melt that inhibits further heat absorption.Pulsed lasers allow rocks to absor... Irradiating hard rocks by a high-power laser can reduce localized hardness in the rocks;however,continuous lasers produce a large amount of melt that inhibits further heat absorption.Pulsed lasers allow rocks to absorb and dissipate energy and avoid melt formation.In this study,200 W nanosecond pulsed laser was used to irradiate granite.The effects of laser parameters on the thermal cracking morphology,temperature field,warming pattern,and Leeb hardness of the granite surface were analyzed.The optimal laser parameters for softening granite were determined by performing objective optimization in MATLAB using granite's melting point as the reference.Nanoindentation techniques were employed to assess the softening characteristics of the granite surface along the longitudinal direction.The results showed that three main forms of thermal damage occurred on the granite surface:oxidative decomposition,spalling,and melting.The damage state was affected by the average laser power,with the pulse width and repetition frequency affecting surface damage differently.Appropriate laser parameters effectively controlled the melt damage on the granite surface,and irradiation with nanosecond pulsed lasers effectively reduced surface hardness.However,excessive power can generate large amounts of hard melts and weaken the softening effect. 展开更多
关键词 nanosecond pulsed laser assisted rock breaking warming characteristics Leeb hardness nanoindentation test softening characteristics
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Capturability distinction analysis of continuous and pulsed guidance laws
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作者 Yuting LU Qinglei HU +2 位作者 Yang YU Tuo HAN Jianying ZHENG 《Chinese Journal of Aeronautics》 2026年第1期472-484,共13页
The capture zones of the continuous and pulsed guidance laws in the pursuit-evasion game are analytically discussed in this paper to provide deep insights into the capturability distinction between the continuous guid... The capture zones of the continuous and pulsed guidance laws in the pursuit-evasion game are analytically discussed in this paper to provide deep insights into the capturability distinction between the continuous guidance law and the pulsed guidance law.Specifically,first,in the pursuit-evasion game,various capture cases are defined regarding the Zero-Effort Miss distance(ZEM)to facilitate the capturability analysis.Then,for both the evader and the pursuer,the Linear-Quadratic Differential Game(LQDG)guidance laws concerning the continuous acceleration and the pulsed acceleration are converted into a unified form.In each capture case,the optimal solution existence conditions are derived,and the corresponding capture zones are formulated.The discussion on the capture zones shows that if the optimal solution exists,the distinction between the pulsed guidance law and the continuous guidance law can be neglected under small guidance effort weight.However,the capture zone of the continuous guidance law is larger than that of the pulsed guidance law with large pursuer guidance effort weight,but smaller with large evader guidance effort weight.Finally,various simulations are conducted to illustrate the distinction of the continuous and pulsed guidance laws,as well as the impact of the acceleration ratio and the time constant ratio on the capturability. 展开更多
关键词 Differential game theory Linear-quadratic differential game pulsed guidance law Capturability Capture zone
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Pulsed Dynamic Water Electrolysis:Mass Transfer Enhancement,Microenvironment Regulation,and Hydrogen Production Optimization
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作者 Xuewei Zhang Wei Zhou +7 位作者 Xiaoxiao Meng Yuming Huang Yang Yu Haiqian Zhao Lijie Wang Fei Sun Jihui Gao Guangbo Zhao 《Nano-Micro Letters》 2026年第3期807-859,共53页
Pulsed dynamic electrolysis(PDE),driven by renewable energy,has emerged as an innovative electrocatalytic conversion method,demonstrating significant potential in addressing global energy challenges and promoting sust... Pulsed dynamic electrolysis(PDE),driven by renewable energy,has emerged as an innovative electrocatalytic conversion method,demonstrating significant potential in addressing global energy challenges and promoting sustainable development.Despite significant progress in various electrochemical systems,the regulatory mechanisms of PDE in energy and mass transfer and the lifespan extension of electrolysis systems,particularly in water electrolysis(WE)for hydrogen production,remain insufficiently explored.Therefore,there is an urgent need for a deeper understanding of the unique contributions of PDE in mass transfer enhancement,microenvironment regulation,and hydrogen production optimization,aiming to achieve low-energy consumption,high catalytic activity,and long-term stability in the generation of target products.Here,this review critically examines the microenvironmental effects of PDE on energy and mass transfer,the electrode degradation mechanisms in the lifespan extension of electrolysis systems,and the key factors in enhancing WE for hydrogen production,providing a comprehensive summary of current research progress.The review focuses on the complex regulatory mechanisms of frequency,duty cycle,amplitude,and other factors in hydrogen evolution reaction(HER)performance within PDE strategies,revealing the interrelationships among them.Finally,the potential future directions and challenges for transitioning from laboratory studies to industrial applications are proposed. 展开更多
关键词 pulsed dynamic electrolysis Water electrolysis Energy and mass transfer MICROENVIRONMENT System stability
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Thickness dependence of the magnetic properties of barium ferrite films prepared by pulsed laser deposition
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作者 Chengbo Zhao Bowei Han +5 位作者 Yuchen Zhao Yang Sun Lichen Wang Ruoshui Liu Yunzhong Chen Dengjing Wang 《Chinese Physics B》 2026年第2期591-594,共4页
BaFe_(12)O_(19)(BaM)thin films with thicknesses ranging from 15 nm–200 nm were deposited on Al_(2)O_(3)(0001)substrates by pulsed laser deposition(PLD).X-ray diffraction patterns show that a buffer layer with a thick... BaFe_(12)O_(19)(BaM)thin films with thicknesses ranging from 15 nm–200 nm were deposited on Al_(2)O_(3)(0001)substrates by pulsed laser deposition(PLD).X-ray diffraction patterns show that a buffer layer with a thickness of nearly 60 nm forms on the substrate,and then a c-axis perpendicularly oriented Ba M thin film grows on the buffer layer.Atomic force microscopy results indicate that the Ba M thin film exhibits a spiral island growth mode on the buffer layer.Magnetic hysteresis loop results confirm that the buffer layer exhibits no significant magnetic anisotropy,while the Ba M thin film exhibits perpendicular magnetic anisotropy.The out-of-plane coercivity decreases with increasing Ba M thin-film thickness due to the combined effect of grain size growth and lattice strain relaxation.The 200 nm thick film exhibits optimum magnetic properties with M_(s)=319 emu/cm^(3) and H_(c)=1546 Oe. 展开更多
关键词 pulsed laser deposition barium hexaferrite film self-made buffer layer perpendicular magnetic anisotropy film thickness
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Low-intensity pulsed ultrasound stimulates proliferation of stem/progenitor cells: what we need to know to translate basic science research into clinical applications 被引量:4
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作者 Yan Tan Yang Guo +4 位作者 Amanda B Reed-Maldonado Zheng Li Guiting Lin Shu-Jie Xia Tom F Lue 《Asian Journal of Andrology》 SCIE CAS CSCD 2021年第6期602-610,共9页
Low-intensity pulsed ultrasound (LIPUS) is a promising therapy that has been increasingly explored in basic research and clinical applications. LIPUS is an appealing therapeutic option as it is a noninvasive treatment... Low-intensity pulsed ultrasound (LIPUS) is a promising therapy that has been increasingly explored in basic research and clinical applications. LIPUS is an appealing therapeutic option as it is a noninvasive treatment that has many advantages, including no risk of infection or tissue damage and no known adverse reactions. LIPUS has been shown to have many benefits including promotion of tissue healing, angiogenesis, and tissue regeneration;inhibition of inflammation and pain relief;and stimulation of cell proliferation and differentiation. The biophysical mechanisms of LIPUS remain unclear and the studies are ongoing. In recent years, more and more research has focused on the relationship between LIPUS and stem/progenitor cells. A comprehensive search of the PubMed and Embase databases to July 2020 was performed. LIPUS has many effects on stem cells. Studies show that LIPUS can stimulate stem cells in vitro;promote stem cell proliferation, differentiation, and migration;maintain stem cell activity;alleviate the problems of insufficient seed cell source, differentiation, and maturation;and circumvent the low efficiency of stem cell transplantation. The mechanisms involved in the effects of LIPUS are not fully understood, but the effects demonstrated in studies thus far have been favorable. Much additional research is needed before LIPUS can progress from basic science research to large-scale clinical dissemination and application. 展开更多
关键词 cellular signaling pathway low-intensity pulsed ultrasound mechanism MECHANOTRANSDUCTION stem cells
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Factors Influencing the Electron Yield of Needle-Ring Pulsed Corona Discharge Electron Source for Negative Ion Mobility Spectrometer 被引量:4
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作者 刘欣 李胜利 李铭书 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第12期1215-1220,共6页
A simple negative ion mobility spectrometer (IMS) is designed and used to investi- gate the factors that influence the number and efficiency of electrons generated by the needle-ring pulsed corona discharge electron... A simple negative ion mobility spectrometer (IMS) is designed and used to investi- gate the factors that influence the number and efficiency of electrons generated by the needle-ring pulsed corona discharge electron source. Simulation with Ansoft Maxwell 12 is carried out to analyze the electric field distribution within the IMS, and to offer the basis and foundation for analyzing the measurement results. The measurement results of the quantities of electrons show that when the drift electric field strength and the ring inner diameter rise, both the number of ef- fective electrons and the effective electron rate are increased. When the discharge voltage becomes stronger, the number of effective electrons goes up while the effective electron rate goes down. In light of the simulation results, mechanisms underlying the effects of drift electric field strength, ring inner diameter, and discharge voltage on the effective electron number and effective electron rate are discussed. These will make great sense for designing negative ion mode IMS using the needle-ring pulsed corona discharge as the electron source. 展开更多
关键词 ion mobility spectrometer electron source pulsed corona discharge effectiveelectrons simulation
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Improvement of Spatial Uniformity of Nanosecond-Pulse Diffuse Discharges in a Multi-Needle-to-Plane Gap 被引量:1
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作者 顾建伟 章程 +2 位作者 王瑞雪 严萍 邵涛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第3期230-235,共6页
Large-scale non-thermal plasmas generated by nanosecond-pulse discharges have been used in various applications, including surface treatment, biomedical treatment, flow con- trol etc. In this paper, atmospheric-pressu... Large-scale non-thermal plasmas generated by nanosecond-pulse discharges have been used in various applications, including surface treatment, biomedical treatment, flow con- trol etc. In this paper, atmospheric-pressure diffuse discharge was produced by a homemade nanosecond-pulse generator with a full width at half maximum of 100 ns and a rise time of 70 ns. In order to increase the discharge area, multi-needle electrodes with a 3~3 array were designed. The electrical characteristics of the diffuse discharge array and optical images were investigated by the voltage-current waveforms and discharge images. The experimental results showed that the intensity of diffuse discharges in the center was significantly weaker than those at the margins, resulting in an inhomogeneous spatial uniformity in the diffuse discharge array. Simulation of the electric field showed that the inhomogeneous spatial uniformity was caused by the non-uniform distribution of the electric field in the diffuse discharge array. Moreover, the spatial uniformity of the diffuse discharge array could be improved by increasing the length of the needle in the centre of the array. Finally, the experimental results confirmed the simulation results, and the spatial uniformity of the nanosecond-pulse diffuse discharge array was significantly improved. 展开更多
关键词 diffuse discharge array nanosecond pulse spatial uniformity electric field
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Numerical Study of Pulsed Dielectric Barrier Discharge at Atmospheric Pressure Under the Needle-Plate Electrode Configuration
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作者 王艳辉 叶换换 +3 位作者 张佼 王奇 张杰 王德真 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第5期478-484,共7页
In this paper, we study the characteristics of atmospheric-pressure pulsed dielectric barrier discharge (DBD) under the needle-plate electrode configuration using a one-dimensional self-consistent fluid model. The r... In this paper, we study the characteristics of atmospheric-pressure pulsed dielectric barrier discharge (DBD) under the needle-plate electrode configuration using a one-dimensional self-consistent fluid model. The results show that, the DBDs driven by positive pulse, negative pulse and bipolar pulse possess different behaviors. Moreover, the two discharges appearing at the rising and the falling phases of per voltage pulse also have different discharge regimes. For the case of the positive pulse, the breakdown field is much lower than that of the negative pulse, and its propagation characteristic is different from the negative pulse DBD. When the DBD is driven by a bipolar pulse voltage, there exists the interaction between the positive and negative pulses, resulting in the decrease of the breakdown field of the negative pulse DBD and causing the change of the discharge behaviors. In addition, the effects of the discharge parameters on the behaviors of pulsed DBD in the needle-plate electrode configuration are also studied. 展开更多
关键词 dielectric barrier discharge unipolar pulsed voltage bipolar pulsed voltage needle-plate electrode numerical modeling GLOW-DISCHARGE
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Pulsed dynamic electrolysis enhanced PEMWE hydrogen production:Revealing the effects of pulsed electric fields on protons mass transport and hydrogen bubble escape 被引量:2
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作者 Xuewei Zhang Wei Zhou +13 位作者 Yuming Huang Liang Xie Tonghui Li Huimin Kang Lijie Wang Yang Yu Yani Ding Junfeng Li Jiaxiang Chen Miaoting Sun Shuo Cheng Xiaoxiao Meng Jihui Gao Guangbo Zhao 《Journal of Energy Chemistry》 2025年第1期201-214,共14页
The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for... The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis(PEMWE)emerging as the preeminent pathway for hydrogen production.Despite remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable obstacle.This impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles detachment.To address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis system.Compared to constant voltage electrolysis(hydrogen production rate:51.6 m L h^(-1),energy consumption:5.37 kWh Nm-^(3)H_(2)),this strategy(hydrogen production rate:66 m L h^(-1),energy consumption:3.83 kWh Nm-^(3)H_(2))increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic(PV)system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 V.The combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis(PDE)dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode surface.As such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport processes.This promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors. 展开更多
关键词 Water electrolysis Hydrogen production pulsed dynamic electrolysis Proton exchange membrane water electrolysis Mass transport
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Generation and regulation of electromagnetic pulses induced by multi-petawatt laser coupling with gas jets 被引量:1
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作者 Qiang-You He Zi-Tao Wang +19 位作者 Zhi-Gang Deng Jie Feng Ya-Dong Xia Xi-Chen Hu Ming-Yang Zhu Jia-Jie Xie Zong-Qiang Yuan Zhi-Meng Zhang Feng Lu Lei Yang Hao Cheng Yu-Ze Li Yang Yan Yan-Lv Fang Chen-Tong Li Wei-Min Zhou Ting-Shuai Li Li-Ming Chen Chen Lin Xue-Qing Yan 《Nuclear Science and Techniques》 2025年第6期136-149,共14页
High-power laser pulses interacting with targets can generate intense electromagnetic pulses(EMPs),which can disrupt physical experimental diagnostics and even damage diagnostic equipment,posing a threat to the reliab... High-power laser pulses interacting with targets can generate intense electromagnetic pulses(EMPs),which can disrupt physical experimental diagnostics and even damage diagnostic equipment,posing a threat to the reliable operation of experiments.In this study,EMPs resulting from multi-petawatt laser irradiating nitrogen gas jets were systematically analyzed and investigated.The experimental results revealed that the EMP amplitude is positively correlated with the quantity and energy of the electrons captured and accelerated by the plasma channel.These factors are reflected by parameters such as laser energy and nitrogen gas jet pressure.Additionally,we propose several potential sources of EMPs produced by laser-irradiated gas jets and separately analyzed their spatiotemporal distributions.The findings provide insight into the mechanisms of EMP generation and introduce a new approach to achieve controllable EMPs by regulating the laser energy and gas jet pressure. 展开更多
关键词 Electromagnetic pulses Multi-petawatt laser Gas jets ELECTRONS
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Pulsed electric current treatment: from regulating non-metallic inclusions to inhibiting submerged entry nozzle clogging 被引量:1
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作者 Wen-wen Yu Jin-gang Qi Heng Cui 《Journal of Iron and Steel Research International》 2025年第4期833-848,共16页
Non-metallic inclusions in steel are a significant challenge,affecting material properties and leading to issues such as stress concentration,cracking,and accelerated corrosion.Current methods for removing inclusions,... Non-metallic inclusions in steel are a significant challenge,affecting material properties and leading to issues such as stress concentration,cracking,and accelerated corrosion.Current methods for removing inclusions,including bubble,electromagnetic stirring,filtration separation,fluid flow,and sedimentation,often struggle with the removal of fine inclusions.Apart from these known methods,pulsed electric current(PEC),as an emerging technology,has demonstrated immense potential and environmental advantages.PEC offers adjustable current parameters and simple equipment,making it an attractive alternative to traditional methods.Its green energy-saving features and excellent results in regulating inclusion morphology and migration,as well as inhibiting submerged entry nozzle(SEN)clogging,make it a promising technology.In comparison to continuous current technology,PEC has shown significant advantages in regulating inclusions,not only improving purification efficiency but also demonstrating outstanding performance in flow stability and energy consumption.The ability of PEC to efficiently reduce inclusion numbers enhances the purity and quality of molten steel,improving its mechanical properties.Currently,the theoretical basis for controlling the movement of inclusions by current is mainly composed of three major theories:the double electric layer theory,electromagnetic force reverse separation theory,and electric free energy drive theory.These theories together form an important framework for researchers to understand and optimize the behavior of impurity movement controlled by electric current.Looking ahead,PEC is expected to pave the way for new solutions in directional regulation of inclusion migration,efficient inclusion removal,SEN clogging prevention,and the purification of molten steel. 展开更多
关键词 pulsed electric current Non-metallic inclusion REGULATION Submerged entry nozzle CLOGGING
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