检索结果-南通市图书馆

Two-dimensional investigation of characteristic parameters and their gradients for the self-generated electric and magnetic fields of laser-induced zirconium plasma

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2024年第5期26卷 138-155页

作者： Tayyaba SAJID Shazia BASHIR Mahreen AKRAM Maira RAZZAQ Khaliq MAHMOOD Centre for Advanced Studies in physics Institute of PhysicsGovernment College University LahoreLahore 54000Pakistan Department of physics Institute of PhysicsGovernment College University LahoreLahore 54000Pakistan

Two-dimensional diagnosis of laser-induced zirconium(Zr)plasma has been experimentally performed using the time-of-flight method by employing Faraday cups in addition to electric and magnetic *** characteristic parameters of laser-induced Zr plasma have been evaluated as a function of different laser irradiances ranging from 4.5 to 11.7 GW cm-2 at different axial positions of 1–4 cm with a fixed radial distance of 2 cm.A well-supporting correlation between the plume parameters and the laser-plasma-produced spontaneous electric and magnetic(E and B)fields was *** measurements of the characteristic parameters and spontaneously induced fields were observed to have an increasing trend with the increasing laser ***,when increasing the spatial distance in both the axial and radial directions,the plasma parameters(electron/ion number density,temperature and kinetic energy)did not show either continuously increasing or decreasing trends due to various kinetic and dynamic processes during the spatial evolution of the ***,the E and B fields were observed to be always diffusing away from the *** radial component of electron number densities remained higher than the axial number density component,whereas the axial ion number density at all laser irradiances and axial distances remained higher than the radial ion number *** higher axial self-generated electric field(SGEF)values than radial SGEF values are correlated with the effective charge-separation mechanism of electrons and *** generation of a self-generated magnetic field is observed dominantly in the radial direction at increasing laser irradiance as compared to the axial one due to the deflection of fast-moving electrons and the persistence of two-electron temperature on the radial axis.

关键词： Faraday cup axial and radial expansion space-charge effect laser-induced zirconium plasma two-electron temperature distribution self-generated electric and magnetic fields

Footprints of axion-like particle in pulsar timing array data and James Webb Space Telescope observations

在线全文

学校读者我要写书评

暂无评论

Science China(physics,Mechanics & Astronomy) 2024年第11期67卷 55-62页

作者： Shu-Yuan Guo Maxim Khlopov Xuewen Liu Lei Wu Yongcheng Wu Bin Zhu Department of physics Yantai UniversityYantai 264005 China institute of physics Southern Federal UniversityRostov on Don 344090 Russia National Research Nuclear University MEPhI(Moscow Engineering physics institute) Moscow 115409 Russia Virtual institute of Astroparticle physics Paris 75018 France Department of physics and institute of Theoretical physics Nanjing Normal UniversityNanjing 210023 China

Several pulsar timing array(PTA) collaborations have recently reported the evidence for a stochastic gravitational-wave background(SGWB), which can unveil the formation of primordial seeds of inhomogeneities in the early universe. With the SGWB parameters inferred from PTAs data, we can make a prediction of the seeds for early galaxy formation from the domain walls in the axion-like particles(ALPs) field distribution. This also naturally provides a solution to the observation of high redshifts by the James Webb Space Telescope. The predicted photon coupling of the ALP is within the reach of future experimental searches.

关键词： stochastic gravitational-wave background pulsar timing array axion-like particle JWST

Consistency between domain wall oscillation modes and spin wave modes in nanostrips

在线全文

学校读者我要写书评

暂无评论

Chinese physics B 2024年第6期33卷 511-516页

作者：董新伟吴振江 Department of physics and institute of Theoretical physics and Astrophysics Xiamen UniversityXiamen 361005China

Investigations on domain wall(DW) and spin wave(SW) modes in a series of nanostrips with different widths and thicknesses have been carried out using micromagnetic simulation. The simulation results show that the frequencies of SW modes and the corresponding DW modes are consistent with each other if they have the same node number along the width direction. This consistency is more pronounced in wide and thin nanostrips, favoring the DW motion driven by *** analysis of the moving behavior of a DW driven by SWs is also carried out. The average DW speed can reach a larger value of ~ 140 m/s under two different SW sources. We argue that this study is very meaningful for the potential application of DW motion driven by SWs.

关键词： micromagnetic simulation domain wall spin wave

Integrated analysis of plasma rotation effect on HL-3 hybrid scenario

在线全文

学校读者我要写书评

暂无评论

Chinese physics B 2024年第8期33卷 329-336页

作者：薛淼郑国尧薛雷李佳鲜王硕杜海龙朱毅仁周月 Southwestern institute of physics Chengdu 610000China

The hybrid scenario,which has good confinement and moderate MHD instabilities,is a proposed operation scenario for international thermonuclear experimental reactor(ITER).In this work,the effect of plasma rotation on the HL-3 hybrid scenario is analyzed with the integrated modeling framework *** results show that toroidal rotation has no obvious effect on confinement with a high line averaged density of n_(bar)~(7)×10^(19)m^(-3).In this case,the ion temperature only changes from 4.7 keV to 4.4 keV with the rotation decreasing from 10^(5) rad/s to 10^(3) rad/s,which means that the turbulent heat transport is not *** in the scenarios characterized by lower densities,such as n_(bar)~4×10^(19)m^(-3),turbulent transport becomes dominant in determining heat *** ion temperature rises from 3.8 keV to 6.1 keV in the core as the rotation velocity increases from 10^(3) rad/s to 10^(5) rad/*** the ion temperature rising,the rotation velocity does not obviously affect electron temperature or ***,it is noteworthy that the variation in rotation velocity does not significantly affect the global confinement of plasma in scenarios with low density or with high density.

关键词： HL-3 hybrid scenario toroidal rotation integrated modeling

Photoelectron momentum distributions of triatomic CO_(2)molecules by circularly polarized attosecond pulses

在线全文

学校读者我要写书评

暂无评论

Chinese physics B 2024年第10期33卷 220-225页

作者： Si-Qi Zhang Jun Zhang Xin-Yu Hao Jing Guo Aihua Liu Xue-Shen Liu institute of Atomic and Molecular physics Jilin UniversityChangchun 130012China School of physics Harbin Institute of TechnologyHarbin 150001China

Molecular-frame photoelectron momentum distributions(MF-PMDs)have been studied for imaging molecular *** investigate the MF-PMDs of CO_(2)molecules exposed to circularly polarized(CP)attosecond laser pulses bysolving the time-dependent Schrodinger equations based on the single-active-electron approximation *** showthat high-frequency photons lead to photoelectron diffraction patterns,indicating molecular *** diffractionpatterns can be illustrated by the ultrafast photoionization ***,for the driving pulses with 30 nm,a deviationbetween MF-PMDs and theoretically predicted results of the ultrafast photoionization models is produced because theCoulomb effect strongly influences the molecular ***,the MF-PMDs rotate in the same directionas the helicity of driving laser *** results also demonstrate that the MF-PMDs in a CP laser pulse are the superpositionof those in the parallel and perpendicular linearly polarized *** simulations efficiently visualize molecularorbital geometries and structures by ultrafast photoelectron ***,we determine the contribution of HOMOand HOMO-1 orbitals to ionization by varying the relative phase and the ratio of these two orbitals.

关键词： molecular-frame photoelectron momentum distributions single-active-electron approximation frames ultrafast photoionization models

Mechanical responses and crystal plasticity model of CoCrNi medium-entropy alloy under ramp wave compression

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第5期9卷 93-108页

作者： Jinlei Dong Xuping Zhang Guiji Wang Xianqian Wu Binqiang Luo Xuemiao Chen Fuli Tan Jianheng Zhao Chengwei Sun institute of Fluid physics China Academy of Engineering PhysicsMianyang 621999China institute of Mechanics Chinese Academy of SciencesBeijing 100190China institute of Applied Electronics China Academy of Engineering PhysicsMianyang 621999China

It is of substantial scientific significance and practical value to reveal and understand the multiscale mechanical properties and intrinsic mechanisms of medium-entropy alloys(MEAs)under high strain rates and *** this study,the mechanical responses and deformation mechanisms of an equiatomic CoCrNi MEA are investigated utilizing magnetically driven ramp wave compression(RWC)with a strain rate of 105 s^(−1).The CoCrNi MEA demonstrates excellent dynamic mechanical responses and yield strength under RWC compared with other advanced *** characterizations reveal that grain refinement and abundant micromechanisms,including dislocation slip,stacking faults,nanotwin network,and Lomer–Cottrell locks,collectively contribute to its excellent performance during ***,dense deformation twins and shear bands intersect,forming a weave-like microstructure that can disperse deformation and enhance *** the basis of these observations,we develop a modified crystal plasticity model with coupled dislocation and twinning mechanisms,providing a relatively accurate quantitative description of the multiscale behavior under *** results of simulations indicate that the activation of multilevel microstructures in CoCrNi MEA is primarily attributable to stress inhomogeneities and localized strain during *** research offers valuable insights into the dynamic mechanical responses of CoCrNi MEA,positioning it as a promising material for use under extreme dynamic conditions.

关键词： deformation alloy microstructure

Spatiotemporal Characteristics of Rainfall over Different Terrain Features in the Middle Reaches of the Yangtze River Basin during the Warm Seasons of 2016–20

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2024年第5期41卷 915-936页

作者： Qian WEI Jianhua SUN Shenming FU Yuanchun ZHANG Xiaofang WANG Key Laboratory of Cloud-Precipitation physics and Severe Storms(LACS) Institute of Atmospheric PhysicsChinese Academy of Sciences(IAP/CAS)Beijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science and TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100029China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Hubei Key Laboratory for heavy Rian Monitoring and Warning Research Institute of Heavy RainChina Meteorological Administration(CMA)Wuhan 430205China

Based on hourly rain gauge data during May–September of 2016–20,we analyze the spatiotemporal distributions of total rainfall(TR)and short-duration heavy rainfall(SDHR;hourly rainfall≥20 mm)and their diurnal variations over the middle reaches of the Yangtze River *** all three types of terrain(i.e.,mountain,foothill,and plain),the amount of TR and SDHR both maximize in June/July,and the contribution of SDHR to TR(CST)peaks in August(amount:23%;frequency:1.74%).Foothill rainfall is characterized by a high TR amount and a high CST(in amount);mountain rainfall is characterized by a high TR frequency but a small CST(in amount);and plain rainfall shows a low TR amount and frequency,but a high CST(in amount).Overall,stations with high TR(amount and frequency)are mainly located over the mountains and in the foothills,while those with high SDHR(amount and frequency)are mainly concentrated in the foothills and plains close to mountainous *** all three types of terrain,the diurnal variations of both TR and SDHR exhibit a double peak(weak early morning and strong late afternoon)and a phase shift from the early-morning peak to the late-afternoon peak from May to *** the late-afternoon peak,the amount of TR and SDHR in the foothills is larger than over the mountains and *** TR intensity in the foothills increases significantly from midnight to afternoon,suggesting that thermal instability may play an important role in this process.

关键词： short duration heavy rainfall diurnal variation foothill rainfall

Breaking the scattering limits of water waves

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第6期11卷 85-86页

作者： Adrià Canós Valero Thomas Weiss Yuri Kivshar institute of physics University of Graz 4th physics institute University of Stuttgart Research School of physics Australian National University

When water, light or sound waves impinge on objects smaller than the wavelength, a scattering process takes place[1]. The scattering of waves plays an essential role in a myriad of natural phenomena. In ocean engineering, enhancing the scattering of water waves allows capturing energy from larger areas, with clear implications for energy harvesting and coastal protection.

关键词：

Davidson base as an appropriate base for the shell model in the case of 1p- and 1h- nuclei

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical physics 2024年第10期76卷 94-100页

作者： Hadi Sobhani Yan-An Luo Amir Jalili Hassan Hassanabadi School of physics Nankai University Department of physics Zhejiang Sci-Tech University institute of Theoretical physics Faculty of Physics University of Warsaw institute of Actuarial Science and Data Analytics UCSI University

This study endeavors to develop an improved set of basis functions for nuclear shell-model calculations. The shell model, a well-established approach to understanding nuclear structure,typically employs the harmonic oscillator potential within the mean-field approximation. Given the extensive validation and consistency of harmonic oscillator results with experimental data,we propose a modification by incorporating a centrifugal term that converges toward the Davidson potential. This potential has been extensively studied, and we aim to extract relevant experimental data for the simplest cases in the shell model, namely one-particle and one-hole nuclei. A comprehensive comparison between the Davidson-based results and the harmonic oscillator calculations is presented to demonstrate the effectiveness of the new basis functions.

关键词： beta decay gamma transition nuclear structure shell-model calculations