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Rock Mass Quality Rating Based on the Multi-Criteria Grey Metric Space
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作者 Miloš Gligoric Zoran Gligoric +3 位作者 Saša Jovanovic Suzana Lutovac Dragan Pamucar Ivan Jankovic 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2635-2664,共30页
Assessment of rock mass quality significantly impacts the design and construction of underground and open-pit mines from the point of stability and economy.This study develops the novel Gromov-Hausdorff distance for r... Assessment of rock mass quality significantly impacts the design and construction of underground and open-pit mines from the point of stability and economy.This study develops the novel Gromov-Hausdorff distance for rock quality(GHDQR)methodology for rock mass quality rating based on multi-criteria grey metric space.It usually presents the quality of surrounding rock by classes(metric spaces)with specified properties and adequate interval-grey numbers.Measuring the distance between surrounding rock sample characteristics and existing classes represents the core of this study.The Gromov-Hausdorff distance is an especially useful discriminant function,i.e.,a classifier to calculate these distances,and assess the quality of the surrounding rock.The efficiency of the developed methodology is analyzed using the Mean Absolute Percentage Error(MAPE)technique.Seven existing methods,such as the Gaussian cloud method,Discriminant method,Mutation series method,Artificial neural network(ANN),Support vector machine(SVM),Grey wolf optimizer and Support vector classification method(GWO-SVC)and Rock mass rating method(RMR)are used for comparison with the proposed GHDQR method.The share of the highly accurate category of 85.71%clearly indicates compliance with actual values obtained by the compared methods.The results of comparisons showed that the model enables objective,efficient,and reliable assessment of rock mass quality. 展开更多
关键词 Rock mass rating MULTI-CRITERIA class metric space interval-grey numbers
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Selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s
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作者 Vladimir I.Kolpakov Sergey V.Fedorov +1 位作者 Ekaterina P.Vinogradova Irina A.Bolotina 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期126-135,共10页
Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters ... Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness. 展开更多
关键词 space debris Meteoric impact Explosion Shaped charge High-velocity aluminum element Segmental liner Combined liner Numerical simulation
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Electron G-Factor Anomaly and the Charge Thickness
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作者 Arlen Young 《Journal of Modern Physics》 2024年第4期435-447,共13页
The electron g-factor relates the magnetic moment to the spin angular momentum. It was originally theoretically calculated to have a value of exactly 2. Experiments yielded a value of 2 plus a very small fraction, ref... The electron g-factor relates the magnetic moment to the spin angular momentum. It was originally theoretically calculated to have a value of exactly 2. Experiments yielded a value of 2 plus a very small fraction, referred to as the g-factor anomaly. This anomaly has been calculated theoretically as a power series of the fine structure constant. This document shows that the anomaly is the result of the electron charge thickness. If the thickness were to be zero, g = 2 exactly, and there would be no anomaly. As the thickness increases, the anomaly increases. An equation relating the g-factor and the surface charge thickness is presented. The thickness is calculated to be 0.23% of the electron radius. The cause of the anomaly is very clear, but why is the charge thickness greater than zero? Using the model of the interior structure of the electron previously proposed by the author, it is shown that the non-zero thickness, and thus the g-factor anomaly, are due to the proposed positive charge at the electron center and compressibility of the electron material. The author’s previous publication proposes a theory for splitting the electron into three equal charges when subjected to a strong external magnetic field. That theory is revised in this document, and the result is an error reduced to 0.4% in the polar angle where the splits occur and a reduced magnetic field required to cause the splits. 展开更多
关键词 Electron G-Factor Anomaly Electron charge Thickness Electron Positive charge Electron mass Thickness Electron Fractionalization Splitting the Electron Electron Compressibility Factor
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High-Resolution Mass Spectroscopy for Revealing the Charge Storage Mechanism in Batteries: Oxamide Materials as an Example
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作者 Chenyang Zhang Yuan Chen +7 位作者 Kun Fan Guoqun Zhang Jincheng Zou Huichao Dai Yanbo Gao Xiaobo Wang Minglei Mao Chengliang Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期195-202,共8页
The pursuit of high-performance electrode materials is highly desired to meet the demand of batteries with high energy and power density.However,a deep understanding of the charge storage mechanism is always challengi... The pursuit of high-performance electrode materials is highly desired to meet the demand of batteries with high energy and power density.However,a deep understanding of the charge storage mechanism is always challenging,which limits the development of advanced electrode materials.Herein,high-resolution mass spectroscopy(HR-MS)is employed to detect the evolution of organic electrode materials during the redox process and reveal the charge storage mechanism,by using small molecular oxamides as an example,which have ortho-carbonyls and are therefore potential electrochemical active materials for batteries.The HR-MS results adequately proved that the oxamides could reversibly store lithium ions in the voltage window of 1.5–3.8 V.Upon deeper reduction,the oxamides would decompose due to the cleavage of the C–N bonds in oxamide structures,which could be proved by the fragments detected by HR-MS,^(1)H NMR,and the generation of NH_(3)after the reduction of oxamide by Li.This work provides a strategy to deeply understand the charge storage mechanism of organic electrode materials and will stimulate the further development of characterization techniques to reveal the charge storage mechanism for developing high-performance electrode materials. 展开更多
关键词 charge storage mechanism high-resolution mass spectroscopy organic batteries organic electrodes oxamides
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Electron Shape Calculated for the Dual-Charge Dual-Mass Model
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作者 Arlen Young 《Journal of Modern Physics》 CAS 2023年第3期198-207,共10页
A model for the internal structure of the electron using classical physics equations has been previously published by the author. The model employs both positive and negative charges and positive and negative masses. ... A model for the internal structure of the electron using classical physics equations has been previously published by the author. The model employs both positive and negative charges and positive and negative masses. The internal attributes of the electron structure were calculated for both ring and spherical shapes. Further examination of the model reveals an instability for the ring shape. The spherical shape appears to be stable, but relies on tensile or compressive forces of the electron material for stability. The model is modified in this document to eliminate the dependency on material forces. Uniform stability is provided solely by balancing electrical and centrifugal forces. This stability is achieved by slightly elongating the sphere along the spin axis to create a prolate ellipsoid. The semi-major axis of the ellipsoid is the spin axis of the electron, and is calculated to be 1.20% longer than the semi-minor axis, which is the radius of the equator. Although the shape deviates slightly from a perfect sphere, the electric dipole moment is zero. In the author’s previously published document, the attributes of the internal components of the electron, such as charge and mass, were calculated and expressed as ratios to the classically measured values for the composite electron. It is interesting to note that all of these ratios are nearly the same as the inverse of the Fine Structure Constant, with differences of less than 15%. The electron model assumed that the outer surface charge was fixed and uniform. By allowing the charge to be mobile and the shape to have a particular ellipticity, it is shown that the calculated charge and mass ratios for the model can be exactly equal to the Fine Structure Constant and the Constant plus one. The electron radius predicted by the model is 15% greater than the Classical Electron Radius. 展开更多
关键词 Electron Shape Classical Electron Model Dual-charge Dual-mass Model Electron Radius Negative mass Electron mass Inconsistency Electron charge Inconsistency Fine Structure Constant
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Coulomb Force, Charge, and Electric Properties under Collision Space-Time
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作者 Espen Gaarder Haug 《Journal of Applied Mathematics and Physics》 2023年第3期686-704,共19页
We have recently published a series of papers on a theory we call collision space-time, that seems to unify gravity and quantum mechanics. In this theory, mass and energy are redefined. We have not so far demonstrated... We have recently published a series of papers on a theory we call collision space-time, that seems to unify gravity and quantum mechanics. In this theory, mass and energy are redefined. We have not so far demonstrated how to make it compatible with electric properties such as charge and the Coulomb force. The aim of this paper is to show how electric properties can be reformulated to make it consistent with collision space-time. It is shown that we need to incorporate the Planck scale into the electric constants to do so. This is also fully possible from a practical point of view, as it has recently been shown how to measure the Planck length independent of other constants and without the need for dimensional analysis. 展开更多
关键词 Coulomb’s Law Elementary charge Planck charge Electric Units Collision space-Time
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Determining the Charge-to-Mass Ratio of the Electron
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作者 Joaquim Bocresion 《Journal of Applied Mathematics and Physics》 2023年第8期2309-2317,共9页
The aim of this lab was to determine an experimental value for the charge-to-mass ratio e/m<sub>e</sub> of the electron. In order to do this, an assembly consisting of Helmholtz coils and a helium-filled f... The aim of this lab was to determine an experimental value for the charge-to-mass ratio e/m<sub>e</sub> of the electron. In order to do this, an assembly consisting of Helmholtz coils and a helium-filled fine beam tube containing an electron gun was used. Electrons were accelerated from rest by the electron gun at a voltage of 201.3 V kept constant across trials. When the accelerated electrons collided with the helium atoms in the fine beam tube, the helium atoms entered an excited state and released energy as light. Since the Helmholtz coils put the electrons into centripetal motion, this resulted in a circular beam of light, the radius of which was measured by taking a picture and using photo analysis. This procedure was used to test currents through the Helmholtz coils ranging from 1.3 A to 1.7 A in increments of 0.1 A. Using a linearization of these data, the experimental value for the charge-to-mass ratio of the electron was found to be 1.850 × 10<sup>11</sup> C/kg, bounded between 1.440 × 10<sup>11</sup> C/kg and 2.465 × 10<sup>11</sup> C/kg. This range of values includes the accepted value of 1.759 × 10<sup>11</sup> C/kg, and yields a percent error of 5.17%. The rather low percent error is a testament to the accuracy of this procedure. During this experiment, the orientation of the ambient magnetic field due to the Earth at the center of the apparatus was not considered. In the future, it would be worthwhile to repeat this procedure, taking care to position the Helmholtz coils in such a way to negate the effects of the Earth’s magnetic field on the centripetal motion of electrons. 展开更多
关键词 Helmholtz Coils charge-to-mass Ratio ELECTRON Magnetic Field
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Space Charges Effect of Static Induction Transistor 被引量:1
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作者 陈金伙 刘肃 +2 位作者 王永顺 李思渊 张福甲 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第3期423-428,共6页
The space charge effect (SCE) of static induction transistor (SIT) that occurs in high current region is systematically studied.The I V equations are deduced and well agree with experimental results.Two kinds of ... The space charge effect (SCE) of static induction transistor (SIT) that occurs in high current region is systematically studied.The I V equations are deduced and well agree with experimental results.Two kinds of barriers are presented in SIT,corresponding to channel voltage barrier control (CVBC) mechanism and space charge limited control (SCLC) mechanism respectively.With the increase of drain voltage,the gradual transferring of operational mechanism from CVBC to SCLC is demonstrated.It points out that CVBC mechanism and its contest relationship with space charge barrier makes the SIT distinctly differentiated from JFET and triode devices,etc.The contest relationship of the two potential barriers also results in three different working regions,which are distinctly marked and analyzed.Furthermore,the extreme importance of grid voltage on SCE is illustrated. 展开更多
关键词 static induction transistor space charge effect space charge potential barrier channel barrier space charge limited control channel voltage barrier control
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Transport characteristics of space charge-dominated multi-species deuterium beam in electrostatic low-energy beam line 被引量:1
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作者 Xiao-Long Lu Yu Zhang +4 位作者 Jun-Run Wang Zhi-Wu Huang Zhan-Wen Ma Yao Yang Ze-En Yao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第4期57-65,共9页
The transport characteristics of a space chargedominated multi-species deuterium beam consisting of D_1^+,D_2^+, and D_3^+ particles in an electrostatic low-energy beam line are studied. First, the envelope equations ... The transport characteristics of a space chargedominated multi-species deuterium beam consisting of D_1^+,D_2^+, and D_3^+ particles in an electrostatic low-energy beam line are studied. First, the envelope equations of the primary D_1^+ beam are derived considering the space charge effects caused by all particles. Second, the evolution of the envelope of the multi-species deuterium beam is simulated using the PIC code TRACK, with the results showing a significant effect of the unwanted beam on the transport of the primary beam. Finally, different injected beam parameters are used to study beam matching, and a new beam extraction system for the existing duoplasmatron source is designed to obtain the ideal injected beam parameters that allow a D_1^+ beam of up to 50 m A to pass unobstructed through the electrostatic low-energy beam transport line in the presence of an unwanted(D_2^+, D_3^+)beam of 20 m A; at the same time, distortions of the beam emittance and particle distributions are observed. 展开更多
关键词 ENVELOPE equation space charge effects MULTI-SPECIES BEAM ELECTROSTATIC LEBT
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Simulation analysis on microscopic discharge characteristics of the bipolar corona of a floating conductor
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作者 杨冬阳 陈坚 +2 位作者 段泽民 肖登明 金之俭 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第8期54-73,共20页
A floating conductor exhibits a bipolar corona phenomenon with microscopic discharge characteristics that are still unclear.In this study,a plasma simulation model of the bipolar corona with 108 chemical reaction equa... A floating conductor exhibits a bipolar corona phenomenon with microscopic discharge characteristics that are still unclear.In this study,a plasma simulation model of the bipolar corona with 108 chemical reaction equations is established by combining hydrodynamics and plasma chemical reactions.The evolution characteristics of electrons,positive ions,negative ions and neutral particles,as well as the distribution characteristics of space charges are analyzed,and the evolutionary flow of microscopic particles is summarized.The results indicate that the positive end of the bipolar corona initiates discharge before the negative end,but the plasma chemistry at the negative end is more vigorous.The electron generation rate can reach 1240 mol(m^(3) s)^(-1),and the dissipation rate can reach 34 mol(m^(3) s)^(-1).The positive ion swarm is dominated by O_(4)^(+),and the maximum generation rate can reach 440 mol((m^(3) s)^(-1).The negative ion swarm is mainly O_(2) and O_(4).The O_(2) content is approximately 1.5-3 times that of O_(4),and the maximum reaction rate can reach 51 mol(m^(3) s)^(-1).The final destination of neutral particles is an accumulation in the form of O_(3) and NO,and the amount of O3 produced is approximately 4-6 times that of NO.The positive end of the bipolar corona is dominated by positive space charges,which continue to develop and spread outwards in the form of a pulse wave.The negative end exhibits a space charge distribution structure of concentrated positive charges and diffused negative charges.The validity of the microscopic simulation analysis is verified by the macroscopic discharge phenomenon. 展开更多
关键词 bipolar corona evolution process floating conductor microscopic discharge characteristics space charge distribution
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Charge resolution in the isochronous mass spectrometry and the mass of ^(51)Co 被引量:2
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作者 Xu Zhou Meng Wang +25 位作者 Yu-Hu Zhang Hu-Shan Xu You-Jin Yuan Jian-Cheng Yang Yu.A.Litvinov S.A.Litvinov Bo Mei Xin-Liang Yan Xing Xu Peng Shuai Yuan-Ming Xing Rui-Jiu Chen Xiang-Cheng Chen Chao-Yi Fu Qi Zeng Ming-Ze Sun Hong-Fu Li Qian Wang Tong Bao Min Zhang Min Si Han-Yu Deng Ming-Zheng Liu Ting Liao Jin-Yang Shi Yu-Nan Song 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第4期30-37,共8页
Isochronous mass spectrometry(IMS)of heavyion storage rings is a powerful tool for the mass measurements of short-lived nuclei.In IMS experiments,masses are determined through precision measurements of the revolution ... Isochronous mass spectrometry(IMS)of heavyion storage rings is a powerful tool for the mass measurements of short-lived nuclei.In IMS experiments,masses are determined through precision measurements of the revolution times of the ions stored in the ring.However,the revolution times cannot be resolved for particles with nearly the same mass-to-charge(m/q)ratios.To overcome this limitation and to extract the accurate revolution times for such pairs of ion species with very close m/q ratios,in our early work on particle identification,we analyzed the amplitudes of the timing signals from the detector based on the emission of secondary electrons.Here,the previous data analysis method is further improved by considering the signal amplitudes,detection efficiencies,and number of stored ions in the ring.A sensitive Z-dependent parameter is introduced in the data analysis,leading to a better resolution of ^(34)Ar^(18+) and ^(51)Co^(27+) with A/Z=17/9.The mean revolution times of ^(34)Ar^(18+) and ^(51)Co^(27+) are deduced,although their time difference is merely 1.8 ps.The uncorrected,overlapped peak of these ions has a full width at half maximum of 7.7 ps.The mass excess of ^(51)Co was determined to be-27;332e41T keV,which is in agreement with the previous value of-27;342e48T keV. 展开更多
关键词 Isochronous mass spectrometry charge resolution Signal amplitude Micro-channel plate ^(51)Co
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Measurement of Electric Field of Space Charge Under Positive Lightning Impulse Voltage 被引量:5
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作者 GENG Yinan ZENG Rong +1 位作者 ZHUANG Chijie WANG Feng 《中国电机工程学报》 EI CSCD 北大核心 2012年第22期I0022-I0022,4,共1页
很多绝缘问题本质上都与电场相关,电场测量是高电压领域的重要研究手段。空间电荷导致电场畸变是流注理论的基础,因此定量测量空间电荷的泊松电场对于研究空气间隙的放电机制有重要意义。利用光电集成电场传感器测量了1m棒–板间隙未发... 很多绝缘问题本质上都与电场相关,电场测量是高电压领域的重要研究手段。空间电荷导致电场畸变是流注理论的基础,因此定量测量空间电荷的泊松电场对于研究空气间隙的放电机制有重要意义。利用光电集成电场传感器测量了1m棒–板间隙未发生放电条件下各点的轴向电场,并与数值仿真结果进行对比,验证了电场传感器进行定量测量的可靠性;对3种电极条件下1m棒–板间隙空间电荷区域外部轴线上各点的电场时域波形进行测量,将空间电荷形成的泊松电场与外加电压形成的拉普拉斯电场分开,定量测量了不同电压幅值下、不同空间位置的泊松电场幅值与变化规律。研究结果为建立并验证空间电荷模型奠定了基础。 展开更多
关键词 电场测量 空间电荷 雷电冲击电压 电场畸变 间隙放电 定量测量 高电压
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Vacuum Black Hole Mass Formula Is a Vanishing Noether Charge 被引量:1
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作者 WU Xiao-Ning GUO Han-Ying HUANG Chao-Guang WU Ke 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第9期309-312,共4页
The Noether current and its variation relation with respect to diffeomorphism invariance of gravitationaltheories have been derived from the horizontal variation and vertical-horizontal bi-variation of the Lagrangian,... The Noether current and its variation relation with respect to diffeomorphism invariance of gravitationaltheories have been derived from the horizontal variation and vertical-horizontal bi-variation of the Lagrangian, respec-tively. For Einstein's GR in the stationary, axisymmetric black holes, the mass formula in vacuum can be derived fromthis Noether current although it definitely vanishes. This indicates that the mass formula of black holes is a vanishingNoether charge in this case. The first law of black hole thermodynamics can also be derived from the variation relationof this vanishing Noether current. 展开更多
关键词 black hole mass formula NOETHER charge DIFFEOMORPHISM INVARIANCE
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Quark Mass Dependence of Nucleon Magnetic Moment and Charge Radii 被引量:1
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作者 MA Wei-Xing ZHOU Li-Juan +1 位作者 GU Yun-Ting PING Rong-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2X期333-336,共4页
Understanding hadron structure within the framework of QCD is an extremely challenging problem. Our purpose here is to explain the model-independent consequences of the approximated chiral symmetry of QCD for two famo... Understanding hadron structure within the framework of QCD is an extremely challenging problem. Our purpose here is to explain the model-independent consequences of the approximated chiral symmetry of QCD for two famous results concerning the quark structure of the nucleon. We show that both the apparent success of the constituent quark model in reproducing the ratio of proton to neutron magnetic moments and the apparent success of the Foldy term in reproducing the observed charge radius of the neutron are coincidental. That is, a relatively small change of the current quark mass would spoil both results. 展开更多
关键词 quark mass nucleon magnetic moment nucleon charge radius
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Electron beam modeling and analyses of the electric field distribution and space charge effect 被引量:1
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作者 Yueling Jiang Quanlin Dong 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期288-293,共6页
In electron beam technology, one of the critical focuses of research and development efforts is on improving the measurement of electron beam parameters. The parameters are closely related to the generation, emission,... In electron beam technology, one of the critical focuses of research and development efforts is on improving the measurement of electron beam parameters. The parameters are closely related to the generation, emission, operation environment, and role of the electron beam and the corresponding medium. In this study, a field calculation method is proposed, and the electric field intensity distribution on the electron beam’s cross-section is analyzed. The characteristics of beam diffusion caused by the space charge effect are investigated in simulation, and the obtained data are compared with the experiment. The simulation demonstrated that the cross-sectional electric field distribution is primarily affected by the electron beam current, current density distribution, and electron beam propagation speed. 展开更多
关键词 electron beam electric field distribution space charge effect
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Numerical Analysis of Space Charge Characteristics in Low-density Polyethylene Nanocomposite Under External DC Electric Field 被引量:6
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作者 ZHOU Yuanxiang ZHANG Ling +1 位作者 SHA Yanchao TIAN Jihuan 《高电压技术》 EI CAS CSCD 北大核心 2013年第8期1813-1820,共8页
The dynamic characteristics of space charge in nanocomposite of low-density polyethylene (LDPE) mixed with inorganic nano- fillers. Different from previous qualitatively theoretical works, we investigated the influenc... The dynamic characteristics of space charge in nanocomposite of low-density polyethylene (LDPE) mixed with inorganic nano- fillers. Different from previous qualitatively theoretical works, we investigated the influence of trap depth, trap volume charge density and injection barrier height on the space charge and the electric field distribution in the nanocomposite under a DC external electric field (100 MV/m) systematically and quantificationally, through numerical simulations based on a bipolar charge transport model. The simulation re- sults showed that, the increase of trap depth would severely distort the balanced electric field distribution with the highest and the lowest electric field of 119 MV/m and 47 MV/m, respectively. It is concluded that the introduction of nanofillers creates more deep traps, which would block space charges by capturing most of them in the vicinity of electrode and hence reduce the local electric field largely. Further theoretical analysis of the simulation indicates that both the high permittivity and the low local electric field of the nanocomposite contri- buted to the increase of injection barrier height, and almost no charge could overcome an injection barrier higher than 1.25 eV. At last, a mechanism of space charge suppression in the LDPE nanocomposite was presented. 展开更多
关键词 纳米复合材料 低密度聚乙烯 直流电场 空间电荷 电荷特性 数值分析 无机纳米填料 陷阱深度
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Forming of Space Charge Wave with Broad Frequency Spectrum in Helical Relativistic Two-Stream Electron Beams 被引量:1
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作者 A.Lysenko I.Volk +1 位作者 A.Serozhko O.Rybalko 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期150-154,共5页
We elaborate a quadratic nonlinear theory of plural interactions of growing space charge wave (SCW) harmonics during the development of the two-stream instability in helical relativistic electron beams. It is found ... We elaborate a quadratic nonlinear theory of plural interactions of growing space charge wave (SCW) harmonics during the development of the two-stream instability in helical relativistic electron beams. It is found that in helical two-stream electron beams the growth rate of the two-stream instability increases with the beam entrance angle. An SCW with the broad frequency spectrum, in which higher harmonics have higher amplitudes, forms when the frequency of the first SCW harmonic is much less than the critical frequency of the two-stream instability. For helical electron beams the spectrum expands with the increase of the beam entrance angle. Moreover, we obtain that utilizing helical electron beams in multiharmonic two-stream superheterodyne free-electron lasers leads to the improvement of their amplification characteristics, the frequency spectrum broadening in multiharmonic signal generation mode, and the reduction of the overall system dimensions. 展开更多
关键词 SCW Forming of space charge Wave with Broad Frequency Spectrum in Helical Relativistic Two-Stream Electron Beams
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Direct Derivation of the Neutrino Mass
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作者 Volodymyr Krasnoholovets 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期621-646,共26页
In this paper, the submicroscopic deterministic concept developed by the author is applied to the problem of the neutrino mass. A particle appears from space considered as a mathematical lattice of primary topological... In this paper, the submicroscopic deterministic concept developed by the author is applied to the problem of the neutrino mass. A particle appears from space considered as a mathematical lattice of primary topological balls, and induces a deformation coat in its surrounding. The principles of the interaction of particles with space and through space between themselves are considered in detail. The approach states that real quarks possess only an integer charge (±e) and when moving they periodically change to the monopole state (&rlarr;g) and hence, canonical particles are dynamic dyons. A neutrino emerges as a squeezed quark when it is in a monopole state, or in other words, the quark monopole state (a bubble in the tessellattice) is transferred to the appropriate lepton monopole state (a speck in the tessellattice). The self-mass (a “rest” mass) for each neutrino flavour is calculated. The calculated value of the self-mass for the electron anti-neutrino is 1.22873978 × 10<sup>-36</sup> kg = 0.68927247 eV/c<sup>2</sup>. The concept of neutrino oscillations is revised, and another postulation is proposed, namely, that the transition from lighter to heavier flavors is due to the inelastic scattering of neutrinos on oncoming scatterers. As a result, the neutrino captures the mass defect, becomes heavier, and therefore the transitions V<sub>e</sub>&xrarr;V<sub>μ</sub> and V<sub>μ</sub>&xrarr;V<sub>τ</sub> occur;thus, the number of light neutrinos decreases in the neutrino flux studied. 展开更多
关键词 charge Inerton mass Defect MONOPOLE NEUTRINO space Tessellattice
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Comparison Between Thermally Stimulated Discharge Method and Photo-stimulated Discharge Method for Measuring Space Charge Traps Energy 被引量:1
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作者 ZHU Zhi'en ZHANG Yewen +2 位作者 AN Zhenlian ZHENG Feihu LEI Qingquan 《高电压技术》 EI CAS CSCD 北大核心 2013年第8期1845-1851,共7页
The space charge behavior of a dielectric under HVDC is influenced by the charge trap energy distribution in it. Hence, we in- vestigated the charge trap distributions in several kinds of typical polymer materials usi... The space charge behavior of a dielectric under HVDC is influenced by the charge trap energy distribution in it. Hence, we in- vestigated the charge trap distributions in several kinds of typical polymer materials using thermally stimulated discharge (TSD) and photo-stimulated discharge (PSD) methods, respectively. The experimental results show that,there is a significant difference between the trap energy distributions obtained by the two methods, but the difference decreases with the increase of the melting point of polymers. This is attributed to the change of the trap center environment during TSD caused by the increasing movements of both main chains and branched chains in polymers. PSD method is more accurate for investigating charge trap distribution in dielectrics, especially for polymers with low melting points. 展开更多
关键词 陷阱分布 空间电荷 热刺激放电 放电方法 光刺激 电法测量 电介质材料 能源
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Relation between space-charge-limiting current and electric field enhancement factor at curved surface cathode 被引量:1
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作者 刘国治 杨占峰 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期394-398,共5页
A two-dimensional solution of space-charge-limiting current for a high current vacuum diode with a spherical cathode is presented. The relation between space-charge-limiting current and electric field enhancement fact... A two-dimensional solution of space-charge-limiting current for a high current vacuum diode with a spherical cathode is presented. The relation between space-charge-limiting current and electric field enhancement factor at the cathode surface for the diode with a curved surface cathode is also discussed. It is shown that compared with the current given by the conventional Child-Langmuir law, which describes the one-dimensional space-charege-limiting current, the two-dimensional space-charge-limiting current in such a diode is enhanced due to the electric-field enhancement along the cathode surface. Among practical parameter ranges, enhancement factor ηb approximately satisfies ηb Aβn, where β is the electric field enhancement factor at the cathode surface, and n is a constant between 1 and 2, which is confirmed to be universal for the diodes with curved surface cathodes. 展开更多
关键词 DIODE space-charge-limiting current intense electron beam
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