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3WQ-400型双气流辅助静电果园喷雾机设计与试验 被引量:41
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作者 周良富 张玲 +4 位作者 薛新宇 丁为民 孙竹 周晴晴 崔龙飞 《农业工程学报》 EI CAS CSCD 北大核心 2016年第16期45-53,共9页
为解决农药雾滴难以沉积到果树叶片背面,克服荷电雾滴荷电量在环境空间中快速衰退的难题。该文提出双气流辅助系统与静电喷雾系统相结合的方法,以拖拉机动力输出轴为液压传动系统动力源,研制了牵引式双气流辅助静电果园喷雾机。试验结... 为解决农药雾滴难以沉积到果树叶片背面,克服荷电雾滴荷电量在环境空间中快速衰退的难题。该文提出双气流辅助系统与静电喷雾系统相结合的方法,以拖拉机动力输出轴为液压传动系统动力源,研制了牵引式双气流辅助静电果园喷雾机。试验结果表明,19 k W的拖拉机动力配置可以满足系统动力要求,轴流风机和离心风机的转速分别为1 400、1 800 r/min可以满足所选试验对象对气流速度的要求;单个喷头喷出的雾滴在0.2 m处的荷质比为1.0 m C/kg,且在喷雾距离为1.8 m处依然带电;风送喷雾系统的垂直雾量分布规律、气流速度分布规律与纺锤型果树生物量分布规律相一致,其最大雾量与气流速度均出现在0.5~1.5 m范围内;在施药量为3.5 L/min,作业速度为0.84 m/s条件下,单侧喷雾时果树叶片正反面雾滴覆盖密度分别为115和47个/cm^2,可以满足防治害虫的要求;冠层前部静电喷雾雾滴覆盖密度比非静电喷雾提高了20%,而冠层后部雾滴覆盖密度仅提高了7.2%。该研究为风送静电喷雾机设计与使用提供了参考。 展开更多
关键词 农业机械 果园 喷雾 风送喷雾 静电喷雾 荷质比 覆盖密度
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不同耦合介质爆破爆炸能量传递效率研究 被引量:16
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作者 李桐 陈明 +2 位作者 叶志伟 卢文波 魏东 《爆炸与冲击》 EI CAS CSCD 北大核心 2021年第6期1-11,共11页
不耦合装药爆破可有效降低孔壁峰值压力,改善爆破效果。针对不同耦合介质爆破时爆炸能量的传递问题,考虑岩体应变率效应,理论分析了爆炸作用下岩体变形及破坏特征,得到不同耦合介质爆破时理论爆炸能量的传递效率,并结合数值模拟研究了... 不耦合装药爆破可有效降低孔壁峰值压力,改善爆破效果。针对不同耦合介质爆破时爆炸能量的传递问题,考虑岩体应变率效应,理论分析了爆炸作用下岩体变形及破坏特征,得到不同耦合介质爆破时理论爆炸能量的传递效率,并结合数值模拟研究了岩体性质、炸药类别及不耦合装药系数对不同耦合介质爆破时爆炸能量传递效率差异的影响。研究结果表明,爆炸能量传递效率与耦合介质相关,装药结构相同时,水耦合爆破比空气耦合爆破爆炸能量传递效率高;不同耦合介质爆破爆炸能量传递效率的差异受爆破岩体、炸药性质及不耦合装药系数等因素影响;装药系数相同耦合介质不同的爆破,岩体强度越高,不同耦合介质爆炸能量传递效率差别越大;岩体性质相同时,不同耦合介质爆破间能量传递效率差异随不耦合装药系数的增大而增大,对于乳化炸药在粉砂岩中的爆破,不耦合装药系数由1.28增至3.44时,水耦合爆破传递入周围岩体的能量由空气耦合爆破的1.45倍增至6.52倍。研究结果可对优化爆破设计、改善爆炸能量分布提供参考。 展开更多
关键词 不耦合装药 耦合介质 爆炸能量 传递效率 岩体
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Numerical investigation of effect of eccentric decoupled charge structure on blasting-induced rock damage 被引量:9
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作者 PAN Cheng XIE Li-xiang +3 位作者 LI Xing LIU Kai GAO Peng-fei TIAN Long-gang 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第2期663-679,共17页
Eccentric decoupling blasting is commonly used in underground excavation.Determination of perimeter hole parameters(such as the blasthole diameter,spacing,and burden)based on an eccentric charge structure is vital for... Eccentric decoupling blasting is commonly used in underground excavation.Determination of perimeter hole parameters(such as the blasthole diameter,spacing,and burden)based on an eccentric charge structure is vital for achieving an excellent smooth blasting effect.In this paper,the Riedel-Hiermaier-Thoma(RHT)model was employed to study rock mass damage under smooth blasting.Firstly,the parameters of the RHT model were calibrated by using the existing SHPB experiment,which were then verified by the existing blasting experiment results.Secondly,the influence of different charge structures on the blasting effect was investigated using the RHT model.The simulation results indicated that eccentric charge blasting has an obvious pressure eccentricity effect.Finally,to improve the blasting effect,the smooth blasting parameters were optimized based on an eccentric charge structure.The overbreak and underbreak phenomena were effectively controlled,and a good blasting effect was achieved with the optimized blasting parameters. 展开更多
关键词 eccentric charge structure smooth blasting rock mass damage RHT model parameter optimization
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Electrode Erosion of a High Energy Impulse Spark Gap Switch 被引量:8
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作者 姚学玲 曾正中 陈景亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第6期3157-3160,共4页
Based on the principle of thermal conduction, three metal alloys (stainless steel, copper-tungsten and graphite) were chosen as the material of the high impulse current discharging switch. Experimental results indic... Based on the principle of thermal conduction, three metal alloys (stainless steel, copper-tungsten and graphite) were chosen as the material of the high impulse current discharging switch. Experimental results indicate that the mass loss and surface erosion morphology of the electrode are related with the electrode material (conductivity σ, melting point Tin, density p and thermal capacity c) and the impulse transferred charge (or energy) per impulse for the same total impulse transferred charge. The experimental results indicate that the mass loss of stainless steel, copper-tungsten and graphite are 380.10 μg/C, 118.10 μg/C and 81.90 μg/C respectively under the condition of a total impulse transferred charge of 525 C and a transferred charge per impulse of 10.5 C. Under the same impulse transferred charge, the mass loss of copper-tungsten(118.10 μg/C) with the transferred charge per impulse at 10.5 C is far larger than the mass loss (38.61μg/C) at a 1.48 C transferred charge per impulse. The electrode erosion mechanism under high energy impulse arcs is analyzed briefly and it is suggested that by selecting high conductive metal or metal alloy as the electrode material of a high energy impulse spark gap switch and setting high erosion resistance material at the top of the electrode, the mass loss of the electrode can be reduced and the life of the switch prolonged. 展开更多
关键词 high energy spark gap switch mass loss erosion morphology impulse transferred charge or transferred energy
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低浓度石灰浆雾滴荷电特性的试验研究 被引量:6
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作者 陈汇龙 李庆利 +2 位作者 袁寿其 刘新爱 崔亚兵 《高电压技术》 EI CAS CSCD 北大核心 2007年第10期83-87,共5页
为深入探索石灰浆液荷电雾化脱硫的机理,对石灰浆雾滴荷电特性进行了研究。通过石灰浆雾滴荷质比、喷雾场的测试和机理分析表明:石灰浆雾滴的荷电效果与浆液流量、雾化角、充电装置结构参数、充电电压等诸多因素有关;荷质比随浆液流量... 为深入探索石灰浆液荷电雾化脱硫的机理,对石灰浆雾滴荷电特性进行了研究。通过石灰浆雾滴荷质比、喷雾场的测试和机理分析表明:石灰浆雾滴的荷电效果与浆液流量、雾化角、充电装置结构参数、充电电压等诸多因素有关;荷质比随浆液流量、雾化角的增大而增大,但雾化角进入稳定值后继续增大流量对提高荷质比的作用不明显;电极放电电压随喷嘴与电极距离、名义雾化角和流量的增大而减小;在本试验条件下,流量<45 L/h时存在最佳电压值,约为11 kV,流量>45 L/h时荷电电压值宜控制在约12 kV;石灰浆雾滴荷电能有效地使雾滴细化而且分布趋向均匀。 展开更多
关键词 高电压 石灰浆 感应充电 雾化角 荷质比 喷雾场 脱硫
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Determination of Atomic Fractions of Isotopes Carbon-13 and Nitrogen-15 Directly in Glicine, L-Leucine, Isoleucine and Alanine
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作者 Levani Eliashvili Lamzira Parulava Vakhtang Betlemidze 《American Journal of Analytical Chemistry》 CAS 2023年第5期229-237,共9页
Using compounds modified by the isotopes carbon-13 and nitrogen-15 helps conduct research in various fields of science, such as medicine, pharmacology, pharmacokinetics, metabolism, agriculture, and others. In the cas... Using compounds modified by the isotopes carbon-13 and nitrogen-15 helps conduct research in various fields of science, such as medicine, pharmacology, pharmacokinetics, metabolism, agriculture, and others. In the case of the availability of reliable, express, and cheap methods, the area of their use will gradually expand. A determination of the atomic fraction of the isotopes carbon-13 and nitrogen-15 directly in glycine, leucine, isoleucine, and alanine is proposed;the modification concerns all centers or one or more identical carbon and nitrogen centers separately, as well as both isotopes at the same time. There are defined mass lines of the mass spectrum of each amino acid, through which the isotopic content of carbon and nitrogen is calculated. The processes that must be taken into account for the determination of the isotopic content are also established. Isotopic analysis of these compounds until now was carried out by transforming them into carbon oxide, dioxide, and molecular nitrogen, and determination of their content in individual centers was impossible. 展开更多
关键词 mass Spectrometer mass Spectrum Fragmentary Ion Ionization mass-to-charge Ratio Intensity of Ionic Current Carbon-13 Nitrogen-15 Atomic Fraction Isotope-Modified
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin mass charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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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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An Electron Model Based on the Fine Structure Constant
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作者 Arlen Young 《Journal of Modern Physics》 CAS 2023年第5期553-561,共9页
In previous publications, the author has proposed a model of the electron’s internal structure, wherein a positively-charged negative mass outer shell and a negatively-charged positive mass central core are proposed ... In previous publications, the author has proposed a model of the electron’s internal structure, wherein a positively-charged negative mass outer shell and a negatively-charged positive mass central core are proposed to resolve the electron’s charge and mass inconsistencies. That model is modified in this document by assuming the electron’s radius is exactly equal to the classical electron radius. The attributes of the internal components of the electron’s structure have been recalculated accordingly. The shape of the electron is also predicted, and found to be slightly aspherical on the order of an oblate ellipsoid. This shape is attributed to centrifugal force and compliant outer shell material. It is interesting to note that all of the electron’s attributes, both external and internal, with the exception of mass and angular moment, are functions of the fine structure constant a, and can be calculated from just three additional constants: electron mass, Planck’s constant, and speed of light. In particular, the ratios of the outer shell charge and mass to the electron charge and mass, respectively, are 3/2a. The ratios of the central core charge and mass to the electron charge and mass, respectively, are 1-(3/2a). Attributes of the electron are compared with those of the muon. Charge and spin angular momentum are the same, while mass, magnetic moment, and radius appear to be related by the fine structure constant. The mass of the electron outer shell is nearly equal to the mass of the muon. The muon internal structure can be modeled exactly the same as for the electron, with exactly the same attribute relationships. 展开更多
关键词 Fine Structure Constant Negative mass Electron Shape Electron Structure Electron mass Inconsistency Electron charge Inconsistency MUON
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Working Fluid Distribution and Charge Regulation Control in Organic Rankine Cycle
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作者 叶振鸿 李新华 +1 位作者 王炜 陈江平 《Journal of Shanghai Jiaotong university(Science)》 EI 2024年第2期188-201,共14页
Charge-based studies,in particular investigations of mass distribution,are still almost absent,although the efficiency of the organic Rankine cycle(ORC)has attracted a great deal of scholarly attention.This paper aims... Charge-based studies,in particular investigations of mass distribution,are still almost absent,although the efficiency of the organic Rankine cycle(ORC)has attracted a great deal of scholarly attention.This paper aims to provide a new perspective on the intrinsic relationship among the mass distribution,phase-zone distribution in the heat exchanger(HEX),charge of working fuid(WF),rotation speed of the pump(RSP),and system performance.A comprehensive ORC simulation model is presented by linking each component's sub-models,including the independent models for HEX,pump,and expander in an object-oriented fashion.The visualization study of mass distribution of the WF in the system is investigated under different working conditions.Furthermore,the volume and mass of the gas phase,two-phase and liquid phase of WF in the HEX and their variation rules are analyzed in-depth.Finally,the strategies of charge reduction considering HEX areas and pipe sizes are investigated.The results show that the model based on the interior-point method provides high levels of accuracy and robustness.The mass ratio of the WF is concentrated in the liquid receiver,especially in the regenerator,which is 32.9%and 21.9%of the total mass,respectively.Furthermore,2.4 kg(6.9%)WF in the system gradually migrates to the high-temperature side as the RSP increases while 6.1 kg(17.4%)WF migrates to the low-temperature side,especially to the condenser,as the charge in the system increases.Output power and efficiency both decrease gradually after the peak due to changes in RSP and charge.Last,reducing heat transfer areas of the condenser and regenerator is the most effective way to reduce WF charge. 展开更多
关键词 SIMULATION organic Rankine cycle(ORC) working fuid charge mass distribution
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Review of electrostatic system parameters,charged droplets characteristics and substrate impact behavior from pesticides spraying 被引量:6
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作者 Samuel Appah Pei Wang +2 位作者 Mingxiong Ou Chen Gong Weidong Jia 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2019年第2期1-9,共9页
Electrostatic spraying application is adopted in crop protection to prevent pest infestation,to improve product quality and to maximize yield.It involves a superposition of charges to pesticide spray droplets to attra... Electrostatic spraying application is adopted in crop protection to prevent pest infestation,to improve product quality and to maximize yield.It involves a superposition of charges to pesticide spray droplets to attract substrate ions at obscured surfaces.The droplets wraparound effect reduces off-target deposition,enhances on-target spray and invariably improves spray efficiency.Electrostatic spraying system works effectively at optimum parameters in combination with charging voltages,application pressures,spraying height regimes,flow rate,travel speed,electrode material,and nozzle orientation.Many combinations of the system parameter settings have been systematically used by researchers for the electrostatic application,but there are unknown specific optimum parameters combinations for pesticide spraying.Since droplets chargeability influences the effectiveness of electrostatic spraying system,the parameters that produce ideal charge to mass ratio determine the functionality of the spraying deposition,retention and surface coverage.This article,therefore,analyses electrostatic system parameters that produce suitably charged droplets characteristics for effective impacting behavior of pesticides on substrates.Increasing applied voltages consequently maximizes charge-mass ratio to optimum and starts declining upon further increase in voltages beyond a critical point.This review further proposes the selection of an optimum electrostatic parameters combination that yields optimum droplets chargeability in pesticide application.Also,it is necessary to investigate the charge property of substrates prior to pesticide application in order to superpose the right opposite charge on spray droplets at rupture time during electrostatic spraying system. 展开更多
关键词 electrostatic spraying charged droplets SUBSTRATES DEPOSITION WRAPAROUND charge-mass ratio
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钻爆法隧道上台阶爆破炮孔装药量精细计算方法
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作者 李传贵 于礼杰 +4 位作者 王冠 杜念伟 王松涛 王术剑 苏威天 《工程爆破》 CSCD 北大核心 2024年第4期73-78,85,共7页
目前隧道钻爆法施工技术日趋成熟,但炮孔装药量的精细计算仍缺乏可靠的经验或理论公式。基于利文斯顿爆破漏斗理论,考虑隧道上台阶爆破方案设计中的炮孔孔距、排距和倾角等因素,提出了倾斜与垂直炮孔负担爆破岩石体积的计算方法。考虑... 目前隧道钻爆法施工技术日趋成熟,但炮孔装药量的精细计算仍缺乏可靠的经验或理论公式。基于利文斯顿爆破漏斗理论,考虑隧道上台阶爆破方案设计中的炮孔孔距、排距和倾角等因素,提出了倾斜与垂直炮孔负担爆破岩石体积的计算方法。考虑岩石坚固性系数、爆生临空面方向等因素的影响,建立了炸药单耗优化计算方法。最后,基于炮孔装药量经验体积计算公式,提出了隧道上台阶爆破炮孔装药量精细计算的方法。依托临沂至滕州高速公路寨山隧道开挖试验段,验证了炮孔装药量计算方法的可靠性,研究成果对指导隧道精细爆破具有重要意义。 展开更多
关键词 隧道工程 钻爆法 装药量 爆破岩石体积 炸药单耗
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The Integer-Fraction Principle of the Digital Electric Charge for Quarks and Quasiparticles 被引量:1
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作者 Ding-Yu Chung 《Journal of Modern Physics》 2016年第10期1150-1159,共10页
In the integer-fraction principle of the digital electric charge, individual integral charge and individual fractional charge are the digital representations of the allowance and the disallowance of irreversible kinet... In the integer-fraction principle of the digital electric charge, individual integral charge and individual fractional charge are the digital representations of the allowance and the disallowance of irreversible kinetic energy, respectively. The disallowance of irreversible kinetic energy for individual fractional charge brings about the confinement of individual fractional charges to restrict irreversible movement resulted from irreversible kinetic energy. Collective fractional charges are confined by the short-distance confinement force field where the sum of the collective fractional charges is integer. As a result, fractional charges are confined and collective. The confinement force field includes gluons in QCD (quantum chromodynamics) for collective fractional charge quarks in hadrons and the magnetic flux quanta for collective fractional charge quasiparticles in the fractional quantum Hall effect (FQHE). The collectivity of fractional charges requires the attachment of energy as flux quanta to bind collective fractional charges. The integer-fraction transformation from integral charges to fractional charges consists of the three steps: 1) the attachment of an even number of flux quanta to individual integral charge fermions to form individual integral charge composite fermions, 2) the attachment of an odd number of flux quanta to individual integral charge composite fermions to form transitional collective integral charge composite bosons, and 3) the conversion of flux quanta into the confinement force field to confine collective fractional charge composite fermions converted from composite bosons. The charges of quarks are fractional, because QCD (the strong force) emerges in the universe that has no irreversible kinetic energy. Kinetic energy emerged in the universe after the emergence of the strong force. The charges of the quasiparticles in the FQHE are fractional because of the confinement by a two-dimensional system, the Landau levels, and an extremely low temperature and the collectivity by high ene 展开更多
关键词 Electric charge Integral charge Fractional charge QUARKS Kinetic Energy Confinement The Fractional Quantum Hall Effect The Theory of Everything The masses of Quarks The mass of Muon The mass of Pion Cosmology
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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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Weight Gain from Static Charging
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作者 Keith W. Koenig 《Open Journal of Applied Sciences》 CAS 2023年第1期89-93,共5页
This paper announces the discovery that a statically charged object gains weight, equal to approximately 7 × 10<sup>-11</sup> grams per excess electron when the object is negatively charged and 5 ... This paper announces the discovery that a statically charged object gains weight, equal to approximately 7 × 10<sup>-11</sup> grams per excess electron when the object is negatively charged and 5 × 10<sup>-11</sup> grams per excess proton when positively charged. The weight gain is not instantaneous but increases to a maximum and then decays with the excess charge. 展开更多
关键词 Weak Electric Fields GRAVITY mass charge Unification DISCOVERY
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蛋白质非酶糖基化导致理化性状改变 被引量:2
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作者 孙子林 刘乃丰 +2 位作者 弓玉祥 童嘉毅 王伯荣 《铁道医学》 2000年第5期290-293,共4页
目的 观察蛋白质糖基化后理化特性的改变。方法 牛血清白蛋白 (BSA)与葡萄糖在体外共同孵育后 ,经聚丙烯酰胺凝胶电泳 (PAGE)及荧光分光光度计测定荧光值和扫描荧光光谱。结果 糖基化BSA荧光光谱改变 ,糖基化终产物 (AGEs)荧光值增... 目的 观察蛋白质糖基化后理化特性的改变。方法 牛血清白蛋白 (BSA)与葡萄糖在体外共同孵育后 ,经聚丙烯酰胺凝胶电泳 (PAGE)及荧光分光光度计测定荧光值和扫描荧光光谱。结果 糖基化BSA荧光光谱改变 ,糖基化终产物 (AGEs)荧光值增加 ;单体BSA在PAGE上向正极泳动加速 ,SDS PAGE近负极段出现新的弥散带。结论 蛋白质非酶糖基化可导致棕色变、阴电荷增加、分子量增大、荧光光谱改变。 展开更多
关键词 蛋白质非酶糖基化 电荷 分子量 荧光光谱
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聚能水压光面爆破技术在米林隧道中的应用 被引量:5
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作者 陈严生 《山西建筑》 2017年第8期176-177,共2页
以拉林铁路米林隧道工程为例,从施工准备、钻孔、清孔、装药、爆破、出碴、初期支护等方面,阐述了聚能水压光面爆破技术的主要施工工艺,经实践证明,该技术简化了装药步骤,缩短了钻爆时间,降低了施工成本。
关键词 隧道 水压光面爆破 聚能管 装药量
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High-performance pulse-width modulation AC/DC controller using novel under voltage lockout circuit according to Energy StarⅥstandard 被引量:3
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作者 Min Qi Quan Sun Donghai Qiao 《Journal of Semiconductors》 EI CAS CSCD 2018年第10期68-74,共7页
This paper proposes a high-performance pulse-width modulation(PWM) AC/DC controller, which can drive a high-voltage(HV) 650-V power metal-oxide-semiconductor field-effect Transistor(MOSFET) in typical applicatio... This paper proposes a high-performance pulse-width modulation(PWM) AC/DC controller, which can drive a high-voltage(HV) 650-V power metal-oxide-semiconductor field-effect Transistor(MOSFET) in typical applications of adapters in portable electronic devices. In order to reduce the standby power consumption and improve the response speed in the start-up state, an improved under voltage lockout(UVLO) circuit without a voltage reference source or comparator is adopted. The AC/DC controller is fabricated using a 40-V 0.8-μm onepoly two-metal(1P2M) CMOS process, and it only occupies 1410 × 730 μm^2. A 12 V/2 A flyback topology for quick-charge application is illustrated as the test circuit, which is currently one of the most advanced power adapters in use. Test values show that the turn-on and the turn-off threshold voltages are 19.318 and 8.01 V, respectively. A high hysteresis voltage of 11.308 V causes the value of the power-charging capacitor to decrease to as low as 1 μF to reduce production cost. In addition, the start-up current of 2.3 μA is extremely small, and is attributed to a reduction in the system's standby power consumption. The final test results of the overall system are proven to meet the Energy Star Ⅵ standard. The controller has already been mass produced for industrial applications. 展开更多
关键词 CONTROLLER UVLO Energy Star VI quick-charge Zener diode mass production
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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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金属-氧化物界面中的金属-载体强相互作用及其对贵金属-氧化铈负载型催化材料性质调控的研究进展 被引量:4
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作者 张涛 张亚文 《中国稀土学报》 CAS CSCD 北大核心 2014年第2期129-142,共14页
从金属-氧化物界面出发,分析了金属-氧化物相互作用的两个决定因素——界面电荷迁移过程和界面物质输运过程。简要介绍了金属-载体强相互作用的发现过程和研究成果,对于金属间成键、特殊形貌结构、界面电荷迁移和界面物质输运这四种常... 从金属-氧化物界面出发,分析了金属-氧化物相互作用的两个决定因素——界面电荷迁移过程和界面物质输运过程。简要介绍了金属-载体强相互作用的发现过程和研究成果,对于金属间成键、特殊形貌结构、界面电荷迁移和界面物质输运这四种常见的金属-载体强相互作用的机制进行了讨论。最后介绍了典型的金属-载体强相互作用体系——贵金属-氧化铈负载型催化剂体系,以及最近在该体系中所取得与金属-载体相互作用相关的研究进展。 展开更多
关键词 金属-载体强相互作用 电荷迁移 物质输运 催化机制 氧化铈 纳米催化
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