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
Experiments with interacting high-velocity flows in a laser plasma can help answer fundamental questions in plasma physics and improve understanding of the mechanisms behind some astrophysical phenomena,such as the fo...Experiments with interacting high-velocity flows in a laser plasma can help answer fundamental questions in plasma physics and improve understanding of the mechanisms behind some astrophysical phenomena,such as the formation of collisionless shock waves,deceleration of accretion flows,and evolution of solar and stellar flares.This work presents the first direct experimental observations of stagnation and redirection of counterstreaming flows(jets)of laser plasma induced by intense laser pulses with intensity I~2×10^(18) W/cm^(2).Hybrid particlein-cell-fluid modeling,which takes into account the kinetic effects of ion motion and the evolution of the pressure tensor for electrons,demonstrates the compression of counterdirected toroidal self-generated magnetic fields embedded in counterstreaming plasma flows.The enhancement of the toroidal magnetic field in the interaction region results in plasma flow stagnation and redirection of the jets across the line of their initial propagation.展开更多
在等离子-脉冲熔化极惰性气体保护复合焊(plasma-pluse metal inter gas welding,Plasma-PMIG)中,异极性电弧间的强烈电磁排斥力严重削弱了等离子弧的挺度与深熔特性.鉴于传统恒定磁场难以适配PMIG脉冲电流剧烈波动引起的排斥力动态变化...在等离子-脉冲熔化极惰性气体保护复合焊(plasma-pluse metal inter gas welding,Plasma-PMIG)中,异极性电弧间的强烈电磁排斥力严重削弱了等离子弧的挺度与深熔特性.鉴于传统恒定磁场难以适配PMIG脉冲电流剧烈波动引起的排斥力动态变化,提出一种同步磁场调控方法,以实现双弧柔性耦合.研制了同步磁场控制装置,通过实时监测PMIG电流波形边沿,输出与脉冲峰/基值匹配的磁场电压;结合XIRIS高速摄像与FLUENT数值模拟,建立了三维磁流体动力学模型,研究了同步磁场电压对304不锈钢焊接电弧形态及温度场的动态影响.结果表明,同步磁场产生的洛伦兹力能动态抵消电磁排斥力.当磁场电压为36 V时,洛伦兹力与排斥力在峰值阶段达到最佳平衡,等离子弧保持垂直且挺度增强,实现了双弧动态柔性耦合,消除了蛇形焊缝及飞溅.最佳工艺参数下熔深提升22.1%,显著改善了传质传热稳定性,大幅提升了成形质量.展开更多
Interfacial interactions between rough mineral particles have garnered considerable attention as they directly determine particle agglomeration and floatability.This study comprehensively investigates the agglomeratio...Interfacial interactions between rough mineral particles have garnered considerable attention as they directly determine particle agglomeration and floatability.This study comprehensively investigates the agglomeration characteristics of siderite particles after argon(Ar)plasma surface modification through settling tests,flocs size measurements,and fractal dimension calculations.Ar plasma surface modification promotes the agglomeration of siderite particles,as evidenced by increased floc size and density.The agglomeration mechanism induced by Ar plasma surface modification is evaluated using a theoretical model combining the surface element integration(SEI)approach,differential geometry,and the composite Simpson's rule.Changes in surface roughness,wettability,and charge are considered in this model.Compared to the unpretreated siderite particles,the energy barrier for interaction of the 30-min Ar plasma-pretreated siderite particles decreases from 2.3×10-^(17)J to 1.6×10^(-17)J.This reduction provides strong evidence for the agglomeration behavior of siderite particles.Furthermore,flotation experiments confirm that Ar plasma surface modification is conducive to the aggregation flotation of siderite.These findings offer crucial insights into particle aggregation and dispersion behaviors,with notable application in mineral flotation.展开更多
The presence of a surface oxide film(B_(2)O_(3))on boron(B)particles significantly compromises their combustion efficiency and kinetic performance in fuel-rich solid propellants.This study proposes an innovative conti...The presence of a surface oxide film(B_(2)O_(3))on boron(B)particles significantly compromises their combustion efficiency and kinetic performance in fuel-rich solid propellants.This study proposes an innovative continuous modification strategy combining non-thermal plasma(NTP)etching with fluorocarbon passivation.Characterization and kinetic analysis revealed that reactive plasma species—including atomic hydrogen(H),electronically excited molecular hydrogen(H_(2)^(*)),vibrationally excited molecular hydrogen(H_(2)v),and hydrogen ions(H^(+))—dominate the reduction of B_(2)O_(3)through lowering the transition energy barrier and shifting the reaction spontaneity.Subsequent argon plasma fragmentation of C_(8)F_(18)generates fluorocarbon radicals that form conformal passivation coatings(thickness:7 nm)on purified boron surfaces.The modified boron particles exhibit 37.5℃lower exothermic peak temperature and 27.2%higher heat release(14.8 kJ/g vs.11.6 kJ/g)compared to untreated counterparts.Combustion diagnostics reveal 194%increase in maximum flame height(135.10 mm vs.46.03 mm)and 134%enhancement in flame propagation rate(4.44 cm/s vs.1.90 cm/s).This NTP-based surface engineering approach establishes a scalable pathway for developing highperformance boron-based energetic composites.展开更多
Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabo...Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabolites mediating the associations ofα-diversity with blood pressure(BP)and BP variability(BPV).Methods Metagenomics and plasma targeted metabolomics were conducted on 523 Chinese participants from the MetaSalt study.The 24-hour,daytime,and nighttime BP and BPV were calculated based on ambulatory BP measurements.Linear mixed models were used to characterize the relationships betweenα-diversity(Shannon and Chao1 index)and BP indices.Mediation analyses were performed to assess the contribution of metabolites to the observed associations.The influence of key metabolites on hypertension was further evaluated in a prospective cohort of 2,169 participants.Results Gut microbial richness(Chao1)was negatively associated with 24-hour systolic BP,daytime systolic BP,daytime diastolic BP,24-hour systolic BPV,and nighttime systolic BPV(P<0.05).Moreover,26 metabolites were strongly associated with richness(Bonferroni P<0.05).Among them,four key metabolites(imidazole propionate,2-hydroxy-3-methylbutyric acid,homovanillic acid,and hydrocinnamic acid)mediated the associations between richness and BP indices(proportions of mediating effects:14.1%–67.4%).These key metabolites were also associated with hypertension in the prospective cohort.For example,each 1-standard deviation unit increase in hydrocinnamic acid significantly reduced the risk of prevalent(OR[95%CI]=0.90[0.82,0.99];P=0.03)and incident hypertension(HR[95%CI]=0.83[0.71,0.96];P=0.01).Conclusion Our results suggest that gut microbial richness correlates with lower BP and BPV,and that certain metabolites mediate these associations.These findings provide novel insights into the pathogenesis and prevention of hypertension.展开更多
Traditional psychiatric diagnosis relies on subjective symptom assessment,lacking objective biomarkers that hinder early detection and personalized treatment.Plasma proteins and polygenic risk score(PRS),as potential ...Traditional psychiatric diagnosis relies on subjective symptom assessment,lacking objective biomarkers that hinder early detection and personalized treatment.Plasma proteins and polygenic risk score(PRS),as potential predictive tools,hold promise for advancing early diagnosis of mental disorders.This study aims to evaluate the predictive potential of proteomic features and PRS in multiple mental illnesses(depression,schizophrenia,and post-traumatic stress disorder(PTSD)).Using participant data from the UK Biobank-Pharma Proteomics Project,we screen protein associations with mental disorders through least absolute shrinkage and selection operator(LASSO)analysis and construct a Cox regression risk prediction model by integrating the PRS.Additionally,we evaluate predictive performance using 6 machine learning methods and Kaplan-Meier survival curves.Our findings reveal distinct predictive patterns across dis-orders.For depression,integrating plasma proteins with PRS significantly improves prediction beyond the clinical model(C-index=0.6322).For schizophrenia,adding plasma proteins enhances predictive performance,whereas PRS provides no significant improvement.For PTSD,neither plasma proteins nor PRS add substantial predictive value beyond clinical variables.Risk stratification analysis demonstrat that all three mental disorders models can clearly distinguish high-risk from low-risk groups(depression:HR=2.34,P<0.001;schizophrenia:HR=5.47,P<0.001;PTSD:HR=3.02,P<0.001).Al-though it shows good performance in short-term prediction,its long-term prediction ability has decreased,and it needs to be further optimized in the future.This study underscores the differential utility of biomarkers across mental disorders and provides a rationale for disorder-specific predictive modeling in precision psychiatry.展开更多
This study investigated enhancing the wear resistance of Ti6Al4V alloys for medical applications by incorporating Ti C nanoreinforcements using advanced spark plasma sintering(SPS). The addition of up to 2.5wt% Ti C s...This study investigated enhancing the wear resistance of Ti6Al4V alloys for medical applications by incorporating Ti C nanoreinforcements using advanced spark plasma sintering(SPS). The addition of up to 2.5wt% Ti C significantly improved the mechanical properties, including a notable 18.2% increase in hardness(HV 332). Fretting wear tests against 316L stainless steel(SS316L) balls demonstrated a 20wt%–22wt% reduction in wear volume in the Ti6Al4V/Ti C composites compared with the monolithic alloy. Microstructural analysis revealed that Ti C reinforcement controlled the grain orientation and reduced the β-phase content, which contributed to enhanced mechanical properties. The monolithic alloy exhibited a Widmanstätten lamellar microstructure, while increasing the Ti C content modified the wear mechanisms from ploughing and adhesion(0–0.5wt%) to pitting and abrasion(1wt%–2.5wt%). At higher reinforcement levels, the formation of a robust oxide layer through tribo-oxide treatment effectively reduced the wear volume by minimizing the abrasive effects and plastic deformation. This study highlights the potential of SPS-mediated Ti C reinforcement as a transformative approach for improving the performance of Ti6Al4V alloys, paving the way for advanced medical applications.展开更多
The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation...The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation supported by experimental evidence remains lacking. This work investigates the effects of fluorine incorporation and electrothermal annealing(ETA) on the current transport process at Ni/β-Ga_(2)O_(3) Schottky contacts. X-ray photoelectron spectroscopy and first-principles calculations confirm the presence of fluorine substitutions for oxygen and oxygen vacancies and their lowering effect on the Schottky barrier heights. Additionally, accurate electrothermal hybrid TCAD simulations validates the extremely short-duration high temperatures(683 K) induced by ETA, which facilitates lattice rearrangement and reduces interface trap states. The interface trap states are quantitatively resolved through frequency-dependent conductance technique, showing the trap density(DT)reduction from(0.88-2.48) × 10^(11) cm^(-2)·eV^(-1) to(0.46-2.09) × 10^(11) cm^(-2)·eV^(-1). This investigation offers critical insights into the β-Ga_(2)O_(3) contacts with the collaborative treatment and solids the promotion of high-performance β-Ga_(2)O_(3) power devices.展开更多
Organosilicone thin films were prepared through plasma polymerization(pp)in a plasma enhance chemical vapour deposition(PECVD)system,utilizing hexamethyldisilazane(HMDSN)as a monomer precursor,at varying distances(25 ...Organosilicone thin films were prepared through plasma polymerization(pp)in a plasma enhance chemical vapour deposition(PECVD)system,utilizing hexamethyldisilazane(HMDSN)as a monomer precursor,at varying distances(25 mm,35 mm,45 mm,55 mm,and 65 mm)from the plasma source to the substrate.Research has examined how the distance between the substrate and plasma source impacts the properties of thin films,including their thickness,surface morphology,and photoluminescence(PL).It was discovered that as the distance increased,both film thickness and PL intensity also increased.Additionally,the film was observed to be more uniform and smoother when deposited 45 mm below the plasma source.展开更多
The generation and reconnection of magneticflux ropes in a plasma irradiated by two Laguerre–Gaussian laser pulses with different frequen-cies and opposite topological charges are investigated numerically by particle-...The generation and reconnection of magneticflux ropes in a plasma irradiated by two Laguerre–Gaussian laser pulses with different frequen-cies and opposite topological charges are investigated numerically by particle-in-cell simulations.It is shown that twisted plasma currents and hence magneticflux ropes can be effectively generated as long as the laser frequency difference matches the electron plasma frequency.More importantly,subsequent reconnection of magneticflux ropes can occur.Typical signatures of magnetic reconnection,such as magnetic island formation and plasma heating,are identified in the reconnection of magneticflux ropes.Notably,it is found that a strong axial magneticfield can be generated on the axis,owing to the azimuthal current induced during the reconnection of the ropes.This indicates that in the reconnection of magneticflux ropes,the energy can be transferred not only from the magneticfield to the plasma but also from the plasma current back to the magneticfield.This work opens a new avenue to the study of magneticflux ropes,which helps in understanding magnetic topology changes,and resultant magnetic energy dissipation,plasma heating,and particle acceleration found in solarflares,and magnetic confinement fusion devices.展开更多
The article discusses the use of pulse-width modulation signals to generate low-temperature atmospheric plasma in an inert gas environment.The results of studies of the energy consumption of a low-temperature plasma g...The article discusses the use of pulse-width modulation signals to generate low-temperature atmospheric plasma in an inert gas environment.The results of studies of the energy consumption of a low-temperature plasma generation system depending on the duty rate,as well as the pulse repetition rate,are presented.The operating modes of the system have been established,in which a minimum of energy consumption is achieved.The issues of evaluating the interaction of plasma with objects based on the analysis of changes in signal parameters in the high-voltage circuit of the generator are also considered.展开更多
The highly efficient manufacturing of atomic-scale smooth β-Ga_(2)O_(3)surface is fairly challenging because β-Ga_(2)O_(3)is a typical difficult-to-machine material.In this study,a novel plasma dry etching method na...The highly efficient manufacturing of atomic-scale smooth β-Ga_(2)O_(3)surface is fairly challenging because β-Ga_(2)O_(3)is a typical difficult-to-machine material.In this study,a novel plasma dry etching method named plasma-based atom-selective etching(PASE)is proposed to achieve the highly efficient,atomic-scale,and damage-free polishing of β-Ga_(2)O_(3).The plasma is excited through the inductive coupling principle and carbon tetrafluoride is utilized as the main reaction gas to etch β-Ga_(2)O_(3).The core of PASE polishing of β-Ga_(2)O_(3)is the remarkable lateral etching effect,which is ensured by both the intrinsic property of the surface and the extrinsic temperature condition.As revealed by density functional theory-based calculations,the intrinsic difference in the etching energy barrier of atoms at the step edge(2.36 eV)and in the terrace plane(4.37 eV)determines their difference in the etching rate,and their etching rate difference can be greatly enlarged by increasing the extrinsic temperature.The polishing of β-Ga_(2)O_(3)based on the lateral etching effect is further verified in the etching experiments.The Sa roughness of β-Ga_(2)O_(3)(001)substrate is reduced from 14.8 nm to 0.057 nm within 120 s,and the corresponding material removal rate reaches up to 20.96μm·min^(−1).The polished β-Ga_(2)O_(3)displays significantly improved crystalline quality and photoluminescence intensity,and the polishing effect of PASE is independent of the crystal face of β-Ga_(2)O_(3).In addition,the competition between chemical etching and physical reconstruction,which is determined by temperature and greatly affects the surface state of β-Ga_(2)O_(3),is deeply studied for the first time.These findings not only demonstrate the high-efficiency and high-quality polishing of β-Ga_(2)O_(3)via atmospheric plasma etching but also hold significant implications for guiding future plasma-based surface manufacturing of β-Ga_(2)O_(3).展开更多
Inductive-pulsed plasma thruster is an in-space propulsion device that generates thrust by ionizing and accelerating plasma through pulsed electromagnetic field.In this paper,the correlation between plasma structure e...Inductive-pulsed plasma thruster is an in-space propulsion device that generates thrust by ionizing and accelerating plasma through pulsed electromagnetic field.In this paper,the correlation between plasma structure evolution and magnetic field permeability is studied using a B-dot probe array system,combing with high-speed camera and electrical parameter measurement.Further discussions explained the mechanism how the magnetic permeation characteristics affect the energy deposition between circuit and plasma.展开更多
The effects of plasma screening on the ^(1)P^(o) resonance states of H-and He below the n=3 and n=4 thresholds of the respective subsystemsare investigated using the stabilization method and correlated exponential wav...The effects of plasma screening on the ^(1)P^(o) resonance states of H-and He below the n=3 and n=4 thresholds of the respective subsystemsare investigated using the stabilization method and correlated exponential wave functions.Two plasma mediums,namely,the Debye plasma and quantum plasma environments are considered.The screened Coulomb potential(SCP)obtained from Debye-Hückel model is used to represent Debye plasma environments and the exponential cosine screened Coulomb potential(ECSCP)obtained from a modified Debye-Hückel model is used to represent quantum plasma environments.The resonance parameters(resonance positions and widths)are presented in terms of the screening parameters.展开更多
BACKGROUND The atherogenic index of plasma(AIP)has been shown to be positively correlated with cardiovascular disease in previous studies.However,it is unclear whether elderly people with long-term high AIP levels are...BACKGROUND The atherogenic index of plasma(AIP)has been shown to be positively correlated with cardiovascular disease in previous studies.However,it is unclear whether elderly people with long-term high AIP levels are more likely to develop coronary heart disease(CHD).Therefore,the aim of this study was to investigate the relationship between AIP trajectory and CHD incidence in elderly people.METHODS 19,194 participants aged≥60 years who had three AIP measurements between 2018 and 2020 were included in this study.AIP was defined as log10(triglyceride/high-density lipoprotein cholesterol).The group-based trajectory model was used to identify different trajectory patterns of AIP from 2018 to 2020.Cox proportional hazards models were used to estimate the hazard ratio(HR)with 95%CI of CHD events between different trajectory groups from 2020 to 2023.RESULTS Three different trajectory patterns were identified through group-based trajectory model:the low-level group(n=7410,mean AIP:-0.25 to-0.17),the medium-level group(n=9981,mean AIP:0.02-0.08),and the high-level group(n=1803,mean AIP:0.38-0.42).During a mean follow-up of 2.65 years,a total of 1391 participants developed CHD.After adjusting for potential confounders,compared with the participants in the low-level group,the HR with 95%CI of the medium-level group and the high-level group were estimated to be 1.24(1.10-1.40)and 1.43(1.19-1.73),respectively.These findings remained consistent in subgroup analyses and sensitivity analyses.CONCLUSIONS There was a significant correlation between persistent high AIP level and increased CHD risk in the elderly.This suggests that monitoring the long-term changes in AIP is helpful to identify individuals at high CHD risk in elderly people.展开更多
The field-reversed configuration(FRC)plasma thruster driven by rotating magnetic field(RMF),abbreviated as the RMF-FRC thruster,is a new type of electric propulsion technology that is expected to accelerate the deep s...The field-reversed configuration(FRC)plasma thruster driven by rotating magnetic field(RMF),abbreviated as the RMF-FRC thruster,is a new type of electric propulsion technology that is expected to accelerate the deep space exploration.An experimental prototype,including diagnostic devices,was designed and constructed based on the principles of the RMF-FRC thruster,with an RMF frequency of 210 kHz and a maximum peak current of 2 kA.Under the rated operating conditions,the initial plasma density was measured to be 5×10^(17)m^(-3),and increased to 2.2×10^(19)m^(-3)after the action of RMF.The coupling efficiency of RMF was about 53%,and the plasma current reached 1.9 kA.The axial magnetic field changed in reverse by 155 Gauss,successfully reversing the bias magnetic field of 60 Gauss,which verifies the formation of FRC plasma.After optimization research,it was found that when the bias magnetic field is 100 Gauss,the axial magnetic field reverse variation caused by FRC is the highest at 164 Gauss.The experimental results are discussed and strategies are proposed to improve the performance of the prototype.展开更多
Due to the continuously increasing building and construction industry,sand has become one of the most questioned raw materials worldwide.However,the available amount of sand suitable for concrete production is orders ...Due to the continuously increasing building and construction industry,sand has become one of the most questioned raw materials worldwide.However,the available amount of sand suitable for concrete production is orders of magnitude lower that the demand and consumption.Even though desert sand is sufficiently available,it is not usable for realizing stable concrete due to its surface shape.Against this background,the suitability of energy-efficient‘cold'dielectric barrier discharge plasma operated at atmospheric pressure for improving the properties of concrete produced from desert sand was investigated in this contribution.It is shown that such plasma treatment allows for a certain roughening and re-shaping of sand grains.As a result,the mass flow of treated sand is decreased due to an improved wedging of sand grains.This leads to a certain increase in compressive strength of concrete samples.Even though this increase is marginal,the suitability of the applied type of plasma for modification of the geometry and surface chemistry of sand grains was proven,showing its basic potential for the treatment and preconditioning of sand used for concrete,mortar or plastering.展开更多
Large-scale proteomics studies can refine our understanding of health and disease and enable precision medicine.Here,we provide a detailed atlas of 2,920 plasma proteins linking to diseases(406 prevalent and 660 incid...Large-scale proteomics studies can refine our understanding of health and disease and enable precision medicine.Here,we provide a detailed atlas of 2,920 plasma proteins linking to diseases(406 prevalent and 660 incident)and 986 health-related traits in 53,026 individuals(median follow-up:14.8 years)from the UK Biobank,representing the most comprehensive proteome profiles to date.This atlas revealed 168,100 protein-disease associations and 554,488 protein-trait associations.Over 650 proteins were shared among at least 50 diseases,and over 1,000 showed sex and age heterogeneity.Furthermore,proteins demonstrated promising potential in disease discrimination(area under the curve[AUC]>0.80 in 183 diseases).Finally,integrating protein quantitative trait locus data determined 474 causal proteins,providing 37 drug-repurposing opportunities and 26 promising targets with favorable safety profiles.These results provide an open-access comprehensive proteome-phenome resource(https://proteome-phenome-atlas.com/)to help elucidate the biological mechanisms of diseases and accelerate the development of disease biomarkers,prediction models,and therapeutic targets.展开更多
The first experiments on laser-driven cylindrical gold foam hohlraums have been performed at the 100 kJ SG-Ⅲ laser facility.Measurements of the expanding plasma emission show that there is less expanding plasma fill ...The first experiments on laser-driven cylindrical gold foam hohlraums have been performed at the 100 kJ SG-Ⅲ laser facility.Measurements of the expanding plasma emission show that there is less expanding plasma fill in foam hohlraums with a wall density of 0.8 g/cm^(3) than in solid gold hohlraums.The radiation temperatures at different angles confirm these results.Simulation results show that the expanding plasma density in the foam hohlraums is lower than in the solid hohlraums,resulting in less expanding plasma emission and higher radiation temperature.Thus,foam gold hohlraums have advantages in reducing wall plasma filling and improving X-ray transmission,which has potential applications in achieving a higher fusion yield.展开更多
基金funding from Grant No. HIDSS-0002 DASHH (Data Science in Hamburg-Helmholtz Graduate School for the Structure of Matter)partially supported by the Helmholtz Imaging platform through the project “Smart Phase.”
文摘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.
基金supported by Russian Science Foundation Grant No.24-62-00032.
文摘Experiments with interacting high-velocity flows in a laser plasma can help answer fundamental questions in plasma physics and improve understanding of the mechanisms behind some astrophysical phenomena,such as the formation of collisionless shock waves,deceleration of accretion flows,and evolution of solar and stellar flares.This work presents the first direct experimental observations of stagnation and redirection of counterstreaming flows(jets)of laser plasma induced by intense laser pulses with intensity I~2×10^(18) W/cm^(2).Hybrid particlein-cell-fluid modeling,which takes into account the kinetic effects of ion motion and the evolution of the pressure tensor for electrons,demonstrates the compression of counterdirected toroidal self-generated magnetic fields embedded in counterstreaming plasma flows.The enhancement of the toroidal magnetic field in the interaction region results in plasma flow stagnation and redirection of the jets across the line of their initial propagation.
文摘在等离子-脉冲熔化极惰性气体保护复合焊(plasma-pluse metal inter gas welding,Plasma-PMIG)中,异极性电弧间的强烈电磁排斥力严重削弱了等离子弧的挺度与深熔特性.鉴于传统恒定磁场难以适配PMIG脉冲电流剧烈波动引起的排斥力动态变化,提出一种同步磁场调控方法,以实现双弧柔性耦合.研制了同步磁场控制装置,通过实时监测PMIG电流波形边沿,输出与脉冲峰/基值匹配的磁场电压;结合XIRIS高速摄像与FLUENT数值模拟,建立了三维磁流体动力学模型,研究了同步磁场电压对304不锈钢焊接电弧形态及温度场的动态影响.结果表明,同步磁场产生的洛伦兹力能动态抵消电磁排斥力.当磁场电压为36 V时,洛伦兹力与排斥力在峰值阶段达到最佳平衡,等离子弧保持垂直且挺度增强,实现了双弧动态柔性耦合,消除了蛇形焊缝及飞溅.最佳工艺参数下熔深提升22.1%,显著改善了传质传热稳定性,大幅提升了成形质量.
基金financially supported by the National Natural Science Foundation of China(No.52204284)the China Postdoctoral Science Foundation(No.2025MD784125)+2 种基金the Natural Science Foundation of Shaanxi Province,China(No.2024JC-YBQN-0365)the Shaanxi Province Postdoctoral Science Foundation,China(No.2025BSHSDZZ363)Outstanding Youth Science Fund of Xi’an University of Science and Technology,China(No.202308)。
文摘Interfacial interactions between rough mineral particles have garnered considerable attention as they directly determine particle agglomeration and floatability.This study comprehensively investigates the agglomeration characteristics of siderite particles after argon(Ar)plasma surface modification through settling tests,flocs size measurements,and fractal dimension calculations.Ar plasma surface modification promotes the agglomeration of siderite particles,as evidenced by increased floc size and density.The agglomeration mechanism induced by Ar plasma surface modification is evaluated using a theoretical model combining the surface element integration(SEI)approach,differential geometry,and the composite Simpson's rule.Changes in surface roughness,wettability,and charge are considered in this model.Compared to the unpretreated siderite particles,the energy barrier for interaction of the 30-min Ar plasma-pretreated siderite particles decreases from 2.3×10-^(17)J to 1.6×10^(-17)J.This reduction provides strong evidence for the agglomeration behavior of siderite particles.Furthermore,flotation experiments confirm that Ar plasma surface modification is conducive to the aggregation flotation of siderite.These findings offer crucial insights into particle aggregation and dispersion behaviors,with notable application in mineral flotation.
基金supported by the National Natural Science Foundation of China(Nos.U2341249,12005076,22205112)the Fundamental Research Funds for the Central Universities(No.2025201012)。
文摘The presence of a surface oxide film(B_(2)O_(3))on boron(B)particles significantly compromises their combustion efficiency and kinetic performance in fuel-rich solid propellants.This study proposes an innovative continuous modification strategy combining non-thermal plasma(NTP)etching with fluorocarbon passivation.Characterization and kinetic analysis revealed that reactive plasma species—including atomic hydrogen(H),electronically excited molecular hydrogen(H_(2)^(*)),vibrationally excited molecular hydrogen(H_(2)v),and hydrogen ions(H^(+))—dominate the reduction of B_(2)O_(3)through lowering the transition energy barrier and shifting the reaction spontaneity.Subsequent argon plasma fragmentation of C_(8)F_(18)generates fluorocarbon radicals that form conformal passivation coatings(thickness:7 nm)on purified boron surfaces.The modified boron particles exhibit 37.5℃lower exothermic peak temperature and 27.2%higher heat release(14.8 kJ/g vs.11.6 kJ/g)compared to untreated counterparts.Combustion diagnostics reveal 194%increase in maximum flame height(135.10 mm vs.46.03 mm)and 134%enhancement in flame propagation rate(4.44 cm/s vs.1.90 cm/s).This NTP-based surface engineering approach establishes a scalable pathway for developing highperformance boron-based energetic composites.
基金supported by the National Science and Technology Major Program for Noncommunicable Chronic Diseases(2023ZD0503500)the National Natural Science Foundation of China(82030102,12126602,91857118)+1 种基金the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2021-I2M-1-010,2019-I2M-2-003)the National High Level Hospital Clinical Research Funding(2022-GSP-GG-1,2022-GSP-GG-2)。
文摘Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabolites mediating the associations ofα-diversity with blood pressure(BP)and BP variability(BPV).Methods Metagenomics and plasma targeted metabolomics were conducted on 523 Chinese participants from the MetaSalt study.The 24-hour,daytime,and nighttime BP and BPV were calculated based on ambulatory BP measurements.Linear mixed models were used to characterize the relationships betweenα-diversity(Shannon and Chao1 index)and BP indices.Mediation analyses were performed to assess the contribution of metabolites to the observed associations.The influence of key metabolites on hypertension was further evaluated in a prospective cohort of 2,169 participants.Results Gut microbial richness(Chao1)was negatively associated with 24-hour systolic BP,daytime systolic BP,daytime diastolic BP,24-hour systolic BPV,and nighttime systolic BPV(P<0.05).Moreover,26 metabolites were strongly associated with richness(Bonferroni P<0.05).Among them,four key metabolites(imidazole propionate,2-hydroxy-3-methylbutyric acid,homovanillic acid,and hydrocinnamic acid)mediated the associations between richness and BP indices(proportions of mediating effects:14.1%–67.4%).These key metabolites were also associated with hypertension in the prospective cohort.For example,each 1-standard deviation unit increase in hydrocinnamic acid significantly reduced the risk of prevalent(OR[95%CI]=0.90[0.82,0.99];P=0.03)and incident hypertension(HR[95%CI]=0.83[0.71,0.96];P=0.01).Conclusion Our results suggest that gut microbial richness correlates with lower BP and BPV,and that certain metabolites mediate these associations.These findings provide novel insights into the pathogenesis and prevention of hypertension.
基金The National Natural Science Foundation of China-Regional Science“Identification of novel drug targets for lung cancer via Mendelian randomization analysis based on blood proteomics”(62362062)The 2025 Xinjiang University Excellent Graduate Innovation Project“Research on identification of therapeutic targets and predictive factors for mental disorders based on proteomics”(XJDX2025YJS151)。
文摘Traditional psychiatric diagnosis relies on subjective symptom assessment,lacking objective biomarkers that hinder early detection and personalized treatment.Plasma proteins and polygenic risk score(PRS),as potential predictive tools,hold promise for advancing early diagnosis of mental disorders.This study aims to evaluate the predictive potential of proteomic features and PRS in multiple mental illnesses(depression,schizophrenia,and post-traumatic stress disorder(PTSD)).Using participant data from the UK Biobank-Pharma Proteomics Project,we screen protein associations with mental disorders through least absolute shrinkage and selection operator(LASSO)analysis and construct a Cox regression risk prediction model by integrating the PRS.Additionally,we evaluate predictive performance using 6 machine learning methods and Kaplan-Meier survival curves.Our findings reveal distinct predictive patterns across dis-orders.For depression,integrating plasma proteins with PRS significantly improves prediction beyond the clinical model(C-index=0.6322).For schizophrenia,adding plasma proteins enhances predictive performance,whereas PRS provides no significant improvement.For PTSD,neither plasma proteins nor PRS add substantial predictive value beyond clinical variables.Risk stratification analysis demonstrat that all three mental disorders models can clearly distinguish high-risk from low-risk groups(depression:HR=2.34,P<0.001;schizophrenia:HR=5.47,P<0.001;PTSD:HR=3.02,P<0.001).Al-though it shows good performance in short-term prediction,its long-term prediction ability has decreased,and it needs to be further optimized in the future.This study underscores the differential utility of biomarkers across mental disorders and provides a rationale for disorder-specific predictive modeling in precision psychiatry.
文摘This study investigated enhancing the wear resistance of Ti6Al4V alloys for medical applications by incorporating Ti C nanoreinforcements using advanced spark plasma sintering(SPS). The addition of up to 2.5wt% Ti C significantly improved the mechanical properties, including a notable 18.2% increase in hardness(HV 332). Fretting wear tests against 316L stainless steel(SS316L) balls demonstrated a 20wt%–22wt% reduction in wear volume in the Ti6Al4V/Ti C composites compared with the monolithic alloy. Microstructural analysis revealed that Ti C reinforcement controlled the grain orientation and reduced the β-phase content, which contributed to enhanced mechanical properties. The monolithic alloy exhibited a Widmanstätten lamellar microstructure, while increasing the Ti C content modified the wear mechanisms from ploughing and adhesion(0–0.5wt%) to pitting and abrasion(1wt%–2.5wt%). At higher reinforcement levels, the formation of a robust oxide layer through tribo-oxide treatment effectively reduced the wear volume by minimizing the abrasive effects and plastic deformation. This study highlights the potential of SPS-mediated Ti C reinforcement as a transformative approach for improving the performance of Ti6Al4V alloys, paving the way for advanced medical applications.
基金supported by the National Natural Science Foundation of China (Grant Nos. 62174019, 52302046, L2424216)the Guangdong Basic and Applied Basic Research Foundation (Grant No. 2024A1515012139)+2 种基金the Major Program (JD) of Hubei Province (Grant No. 2023BAA009)the Knowledge Innovation Program of Wuhan-Shuguang Project (Grant No. 2023010201020262)the Basic Research Program of Jiangsu (Grant No. BK20230268)。
文摘The interfacial properties of Schottky contacts crucially affect the performance of power devices. While a few studies have explored the impact of fluorine on Schottky contacts, a comprehensive theoretical explanation supported by experimental evidence remains lacking. This work investigates the effects of fluorine incorporation and electrothermal annealing(ETA) on the current transport process at Ni/β-Ga_(2)O_(3) Schottky contacts. X-ray photoelectron spectroscopy and first-principles calculations confirm the presence of fluorine substitutions for oxygen and oxygen vacancies and their lowering effect on the Schottky barrier heights. Additionally, accurate electrothermal hybrid TCAD simulations validates the extremely short-duration high temperatures(683 K) induced by ETA, which facilitates lattice rearrangement and reduces interface trap states. The interface trap states are quantitatively resolved through frequency-dependent conductance technique, showing the trap density(DT)reduction from(0.88-2.48) × 10^(11) cm^(-2)·eV^(-1) to(0.46-2.09) × 10^(11) cm^(-2)·eV^(-1). This investigation offers critical insights into the β-Ga_(2)O_(3) contacts with the collaborative treatment and solids the promotion of high-performance β-Ga_(2)O_(3) power devices.
基金the AECS for its financial support of this study
文摘Organosilicone thin films were prepared through plasma polymerization(pp)in a plasma enhance chemical vapour deposition(PECVD)system,utilizing hexamethyldisilazane(HMDSN)as a monomer precursor,at varying distances(25 mm,35 mm,45 mm,55 mm,and 65 mm)from the plasma source to the substrate.Research has examined how the distance between the substrate and plasma source impacts the properties of thin films,including their thickness,surface morphology,and photoluminescence(PL).It was discovered that as the distance increased,both film thickness and PL intensity also increased.Additionally,the film was observed to be more uniform and smoother when deposited 45 mm below the plasma source.
基金supported by the National Natural Science Foundation of China(Grant Nos.12375236 and 12135009)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA25050100 and XDA25010100).
文摘The generation and reconnection of magneticflux ropes in a plasma irradiated by two Laguerre–Gaussian laser pulses with different frequen-cies and opposite topological charges are investigated numerically by particle-in-cell simulations.It is shown that twisted plasma currents and hence magneticflux ropes can be effectively generated as long as the laser frequency difference matches the electron plasma frequency.More importantly,subsequent reconnection of magneticflux ropes can occur.Typical signatures of magnetic reconnection,such as magnetic island formation and plasma heating,are identified in the reconnection of magneticflux ropes.Notably,it is found that a strong axial magneticfield can be generated on the axis,owing to the azimuthal current induced during the reconnection of the ropes.This indicates that in the reconnection of magneticflux ropes,the energy can be transferred not only from the magneticfield to the plasma but also from the plasma current back to the magneticfield.This work opens a new avenue to the study of magneticflux ropes,which helps in understanding magnetic topology changes,and resultant magnetic energy dissipation,plasma heating,and particle acceleration found in solarflares,and magnetic confinement fusion devices.
文摘The article discusses the use of pulse-width modulation signals to generate low-temperature atmospheric plasma in an inert gas environment.The results of studies of the energy consumption of a low-temperature plasma generation system depending on the duty rate,as well as the pulse repetition rate,are presented.The operating modes of the system have been established,in which a minimum of energy consumption is achieved.The issues of evaluating the interaction of plasma with objects based on the analysis of changes in signal parameters in the high-voltage circuit of the generator are also considered.
基金supported by the National Natural Science Foundation of China(52375437,52035009)the Natural Science Foundation of Guangdong Province(2024B1515020027)+2 种基金the Shenzhen Science and Technology Program(Grant No.KQTD20170810110250357)for the financial supportthe assistance of SUSTech Core Research Facilitiessupported by Shenzhen Engineering Research Center for Semiconductorspecific Equipment。
文摘The highly efficient manufacturing of atomic-scale smooth β-Ga_(2)O_(3)surface is fairly challenging because β-Ga_(2)O_(3)is a typical difficult-to-machine material.In this study,a novel plasma dry etching method named plasma-based atom-selective etching(PASE)is proposed to achieve the highly efficient,atomic-scale,and damage-free polishing of β-Ga_(2)O_(3).The plasma is excited through the inductive coupling principle and carbon tetrafluoride is utilized as the main reaction gas to etch β-Ga_(2)O_(3).The core of PASE polishing of β-Ga_(2)O_(3)is the remarkable lateral etching effect,which is ensured by both the intrinsic property of the surface and the extrinsic temperature condition.As revealed by density functional theory-based calculations,the intrinsic difference in the etching energy barrier of atoms at the step edge(2.36 eV)and in the terrace plane(4.37 eV)determines their difference in the etching rate,and their etching rate difference can be greatly enlarged by increasing the extrinsic temperature.The polishing of β-Ga_(2)O_(3)based on the lateral etching effect is further verified in the etching experiments.The Sa roughness of β-Ga_(2)O_(3)(001)substrate is reduced from 14.8 nm to 0.057 nm within 120 s,and the corresponding material removal rate reaches up to 20.96μm·min^(−1).The polished β-Ga_(2)O_(3)displays significantly improved crystalline quality and photoluminescence intensity,and the polishing effect of PASE is independent of the crystal face of β-Ga_(2)O_(3).In addition,the competition between chemical etching and physical reconstruction,which is determined by temperature and greatly affects the surface state of β-Ga_(2)O_(3),is deeply studied for the first time.These findings not only demonstrate the high-efficiency and high-quality polishing of β-Ga_(2)O_(3)via atmospheric plasma etching but also hold significant implications for guiding future plasma-based surface manufacturing of β-Ga_(2)O_(3).
基金Project supported by the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(Grant No.T2221002)the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.12305286)。
文摘Inductive-pulsed plasma thruster is an in-space propulsion device that generates thrust by ionizing and accelerating plasma through pulsed electromagnetic field.In this paper,the correlation between plasma structure evolution and magnetic field permeability is studied using a B-dot probe array system,combing with high-speed camera and electrical parameter measurement.Further discussions explained the mechanism how the magnetic permeation characteristics affect the energy deposition between circuit and plasma.
基金Supported by the Natural Science Foundation of Heilongjiang Province(LH2024A025)。
文摘The effects of plasma screening on the ^(1)P^(o) resonance states of H-and He below the n=3 and n=4 thresholds of the respective subsystemsare investigated using the stabilization method and correlated exponential wave functions.Two plasma mediums,namely,the Debye plasma and quantum plasma environments are considered.The screened Coulomb potential(SCP)obtained from Debye-Hückel model is used to represent Debye plasma environments and the exponential cosine screened Coulomb potential(ECSCP)obtained from a modified Debye-Hückel model is used to represent quantum plasma environments.The resonance parameters(resonance positions and widths)are presented in terms of the screening parameters.
基金supported by the National Key Research and Development Program of China(2017YFC1307705).
文摘BACKGROUND The atherogenic index of plasma(AIP)has been shown to be positively correlated with cardiovascular disease in previous studies.However,it is unclear whether elderly people with long-term high AIP levels are more likely to develop coronary heart disease(CHD).Therefore,the aim of this study was to investigate the relationship between AIP trajectory and CHD incidence in elderly people.METHODS 19,194 participants aged≥60 years who had three AIP measurements between 2018 and 2020 were included in this study.AIP was defined as log10(triglyceride/high-density lipoprotein cholesterol).The group-based trajectory model was used to identify different trajectory patterns of AIP from 2018 to 2020.Cox proportional hazards models were used to estimate the hazard ratio(HR)with 95%CI of CHD events between different trajectory groups from 2020 to 2023.RESULTS Three different trajectory patterns were identified through group-based trajectory model:the low-level group(n=7410,mean AIP:-0.25 to-0.17),the medium-level group(n=9981,mean AIP:0.02-0.08),and the high-level group(n=1803,mean AIP:0.38-0.42).During a mean follow-up of 2.65 years,a total of 1391 participants developed CHD.After adjusting for potential confounders,compared with the participants in the low-level group,the HR with 95%CI of the medium-level group and the high-level group were estimated to be 1.24(1.10-1.40)and 1.43(1.19-1.73),respectively.These findings remained consistent in subgroup analyses and sensitivity analyses.CONCLUSIONS There was a significant correlation between persistent high AIP level and increased CHD risk in the elderly.This suggests that monitoring the long-term changes in AIP is helpful to identify individuals at high CHD risk in elderly people.
基金supported by National Natural Science Foundation of China (NSFC) (Nos.62201217 and 51821005)。
文摘The field-reversed configuration(FRC)plasma thruster driven by rotating magnetic field(RMF),abbreviated as the RMF-FRC thruster,is a new type of electric propulsion technology that is expected to accelerate the deep space exploration.An experimental prototype,including diagnostic devices,was designed and constructed based on the principles of the RMF-FRC thruster,with an RMF frequency of 210 kHz and a maximum peak current of 2 kA.Under the rated operating conditions,the initial plasma density was measured to be 5×10^(17)m^(-3),and increased to 2.2×10^(19)m^(-3)after the action of RMF.The coupling efficiency of RMF was about 53%,and the plasma current reached 1.9 kA.The axial magnetic field changed in reverse by 155 Gauss,successfully reversing the bias magnetic field of 60 Gauss,which verifies the formation of FRC plasma.After optimization research,it was found that when the bias magnetic field is 100 Gauss,the axial magnetic field reverse variation caused by FRC is the highest at 164 Gauss.The experimental results are discussed and strategies are proposed to improve the performance of the prototype.
基金funded by the Bundesministerium für Bildung und Forschung(Nos.13FH6I06IA and 13FH6I08IA)。
文摘Due to the continuously increasing building and construction industry,sand has become one of the most questioned raw materials worldwide.However,the available amount of sand suitable for concrete production is orders of magnitude lower that the demand and consumption.Even though desert sand is sufficiently available,it is not usable for realizing stable concrete due to its surface shape.Against this background,the suitability of energy-efficient‘cold'dielectric barrier discharge plasma operated at atmospheric pressure for improving the properties of concrete produced from desert sand was investigated in this contribution.It is shown that such plasma treatment allows for a certain roughening and re-shaping of sand grains.As a result,the mass flow of treated sand is decreased due to an improved wedging of sand grains.This leads to a certain increase in compressive strength of concrete samples.Even though this increase is marginal,the suitability of the applied type of plasma for modification of the geometry and surface chemistry of sand grains was proven,showing its basic potential for the treatment and preconditioning of sand used for concrete,mortar or plastering.
文摘Large-scale proteomics studies can refine our understanding of health and disease and enable precision medicine.Here,we provide a detailed atlas of 2,920 plasma proteins linking to diseases(406 prevalent and 660 incident)and 986 health-related traits in 53,026 individuals(median follow-up:14.8 years)from the UK Biobank,representing the most comprehensive proteome profiles to date.This atlas revealed 168,100 protein-disease associations and 554,488 protein-trait associations.Over 650 proteins were shared among at least 50 diseases,and over 1,000 showed sex and age heterogeneity.Furthermore,proteins demonstrated promising potential in disease discrimination(area under the curve[AUC]>0.80 in 183 diseases).Finally,integrating protein quantitative trait locus data determined 474 causal proteins,providing 37 drug-repurposing opportunities and 26 promising targets with favorable safety profiles.These results provide an open-access comprehensive proteome-phenome resource(https://proteome-phenome-atlas.com/)to help elucidate the biological mechanisms of diseases and accelerate the development of disease biomarkers,prediction models,and therapeutic targets.
基金support from the National Natural Science Foundation of China(Grant Nos.11775204 and 12105269)the Presidential Foundation of the China Academy of Engineering Physics(Grant No.YZJJLX2018011)。
文摘The first experiments on laser-driven cylindrical gold foam hohlraums have been performed at the 100 kJ SG-Ⅲ laser facility.Measurements of the expanding plasma emission show that there is less expanding plasma fill in foam hohlraums with a wall density of 0.8 g/cm^(3) than in solid gold hohlraums.The radiation temperatures at different angles confirm these results.Simulation results show that the expanding plasma density in the foam hohlraums is lower than in the solid hohlraums,resulting in less expanding plasma emission and higher radiation temperature.Thus,foam gold hohlraums have advantages in reducing wall plasma filling and improving X-ray transmission,which has potential applications in achieving a higher fusion yield.
