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Dimensional Measurement of Complete-connective Network under the Condition of Particle’s Fission and Growth at a Constant Rate
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作者 JinSong Wang BeiBei Hu 《Journal of Software Engineering and Applications》 2012年第12期42-45,共4页
We construct a complete-connective regular network based on Self-replication Space and the structural principles of cantor set and Koch curve. A new definition of dimension is proposed in the paper, and we also invest... We construct a complete-connective regular network based on Self-replication Space and the structural principles of cantor set and Koch curve. A new definition of dimension is proposed in the paper, and we also investigate a simplified method to calculate the dimension of two regular networks. By the study results, we can get a extension: the formation of Euclidean space may be built by the process of the Big Bang's continuously growing at a constant rate of three times. 展开更多
关键词 particle’s fission REGULAR fractals the complete-connective NETWORK NETWORK dimension
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Correlative Measurements of Fission Fragments and Light Particles(α,p)in  Reactions of ^(40)Ar+^(209)Bi,^(nat)Ag at 25MeV/u
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作者 Wu Enjiu Jing Genming +11 位作者 Yin Shuzhi Zheng Jiwen Tan Jilian Song Mintao Jin Weiyang Zhang Chun Li Zhuyu Wu Heyu Guo Zhongyan Wang Shufang He Zhiyong Jiang Dongxing and Qian Xing 《IMP & HIRFL Annual Report》 1994年第0期13-14,共2页
Correlative Measurements of Fission Fragments and Light Particles(α,p)in Reactions of ^(40)Ar+^(209)Bi,^(nat)A... Correlative Measurements of Fission Fragments and Light Particles(α,p)in Reactions of ^(40)Ar+^(209)Bi,^(nat)Ag at 25MeV/u¥WuE?.. 展开更多
关键词 AG Ar BI Correlative fission FRAGMENTs LIGHT MeV Measurements particles
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梅毒螺旋体抗体最佳S/CO截断值在梅毒筛查中的应用价值
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作者 王靖 李小全 +4 位作者 刘敏 杨志立 徐植 赵雅淳 王丽 《实用中西医结合临床》 2024年第10期1-5,共5页
目的 以梅毒螺旋体凝集试验(TPPA)作为确认试验,确立酶联免疫吸附试验(ELISA)法S/CO值与梅毒阳性最佳截断值,减少不必要的TPPA确认重复。方法 选取2022年10月至2023年10月在医院进行梅毒螺旋体(TP)抗体检测的血清标本22 500例,以ELISA... 目的 以梅毒螺旋体凝集试验(TPPA)作为确认试验,确立酶联免疫吸附试验(ELISA)法S/CO值与梅毒阳性最佳截断值,减少不必要的TPPA确认重复。方法 选取2022年10月至2023年10月在医院进行梅毒螺旋体(TP)抗体检测的血清标本22 500例,以ELISA法为梅毒初次筛查试验,采用TPPA和甲苯胺红不加热血清试验(TRUST)对所有反应结果进行复核和确认。分析376例有反应性标本中的S/CO值与TPPA的关系,使用受试者操作特征曲线(ROC)确定ELISA法S/CO值与TPPA阳性最佳截断值。根据S/CO最佳截断值,比较梅毒不同反式筛查策略需要TPPA确认的标本数量。结果 当S/CO≥6.6时,TPPA与ELISA结果一致,特异性和阳性预测值均为100.00%,S/CO=6.6时为最佳截断值;使用欧洲疾病预防与控制中心(ECDC)策略时,376例筛查反应性样本(100.00%,376/376)需TPPA确认;使用美国疾病控制与预防中心(CDC)策略时,TPPA还需确认217例(57.71%,217/376);本研究只有122例(32.45%,122/376)需进行TPPA确认。结论 采用ELISA法梅毒反式筛查策略不受TRUST结果影响,当S/CO≥6.6时不需要进行TPPA确认,与ECDC和CDC反式策略相比,本研究有67.55%的筛查反应样本不必进行TPPA确认,经济且节约时间和人力。 展开更多
关键词 梅毒 s/CO值 最佳截断值 TPPA
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经验小波变换和改进S变换结合的电能质量检测与识别方法
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作者 李宁 王茹月 朱龙辉 《电气传动》 2024年第5期26-33,72,共9页
为分析不确定干扰因素影响下的实际电力网络电能质量问题,提出一种经验小波变换(EWT)和改进S变换相结合的电能质量检测与识别方法。该方法一方面利用EWT联合归一化直接正交(NDQ)算法和奇异值分解(SVD)算法准确提取调幅-调频分量的频率... 为分析不确定干扰因素影响下的实际电力网络电能质量问题,提出一种经验小波变换(EWT)和改进S变换相结合的电能质量检测与识别方法。该方法一方面利用EWT联合归一化直接正交(NDQ)算法和奇异值分解(SVD)算法准确提取调幅-调频分量的频率、幅值和时间参数,另一方面考虑到EWT算法在高噪声环境下瞬时幅值波动的问题,引入改进S变换提取高噪声干扰下的电能质量扰动时频信息,最后,基于EWT和改进S变换提取的扰动特征向量,利用基于改进粒子群优化算法(IPSO)优化支持向量机(SVM)的电能质量扰动识别分类器实现扰动类型的精确识别。仿真和实验表明所提方法在复合扰动识别分类时平均识别准确率为93.23%,且能够准确识别4种实测扰动信号。 展开更多
关键词 电能质量 扰动检测识别 经验小波变换 快速多分辨率s变换 改进粒子群优化 支持向量机
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Numerical Investigation of Penetration in Ceramic/Aluminum Targets Using Smoothed Particle Hydrodynamics Method and Presenting a Modified Analytical Model 被引量:8
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作者 Ehsan Hedayati Mohammad Vahedi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2017年第3期295-323,共29页
Radius of ceramic cone can largely contribute into final solution of analytic models of penetration into ceramic/metal targets.In the present research,a modified model based on radius of ceramic cone was presented for... Radius of ceramic cone can largely contribute into final solution of analytic models of penetration into ceramic/metal targets.In the present research,a modified model based on radius of ceramic cone was presented for ceramic/aluminum targets.In order to investigate and evaluate accuracy of the presented analytic model,obtained results were compared against the results of the Florence’s analytic model and also against numerical modeling results.The phenomenon of impact onto ceramic/aluminum composites were modeled using smoothed particle hydrodynamics(SPH)implemented utilizing ABAQUS Software.Results indicated that,with increasing initial velocity and ceramic thickness and decreasing support layer thickness,the radius of ceramic cone decreases;this ends up increasing residual velocity of the projectile and penetration time and extending the area across which the pressure is distributed.These findings indicate enhanced levels of target energy absorption and the required energy for bending and tensioning the target.As such,it can be observed that,at the same thickness and areal density,the ceramic target has its efficiency enhanced with increasing ceramic thickness and decreasing the support layer thickness.Finally,the results revealed that the associated data with SPH confirm the modified analytic model at higher accuracy than the Florence’s analytic model. 展开更多
关键词 smoothed particle HYDRODYNAMICs Florence’s ANALYTIC MODEL MODIFIED analytical MODEL energy absorption ABAQUs PENETRATION
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Macroscopic Young’s Elastic Modulus Model of Particle Packing Rock Layers 被引量:1
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作者 Cheng-Yao Guan Jia-Fu Qi +4 位作者 Nan-Sheng Qiu Guo-Chun Zhao Qiao Yang Xiang-Dong Bai Chao Wang 《Open Journal of Geology》 2012年第3期198-202,共5页
Based on the Hertzian granular contact mechanics model, the paper built up a Macroscopic Young’s Elastic Modulus of particle/granular packing rock layers, and built up a ties to connecting Young’s Elastic Modulus of... Based on the Hertzian granular contact mechanics model, the paper built up a Macroscopic Young’s Elastic Modulus of particle/granular packing rock layers, and built up a ties to connecting Young’s Elastic Modulus of sand particle in Meso and the Macroscopic Young’s Modulus of granular packing rock layers. The Macroscopic Young’s Modulus of granular packing rock layers is far less than the Young’s Modulus of sand particle. The Macroscopic Young’s Modulus of granular packing rock layers is proportioned to the powers of 1/3 of the vertical contact force of sand particles. The Macroscopic Young’s Modulus is inversely proportional to particle diameter. The paper calculated the vertical contact force of five types aligning mode of the particles. When equal stress, the increased of the coordination number lead to the decrease of the contact force fn, this lead to the coordination number is an inverse proportion to Macroscopic Young’s Modulus. But the larger coordination number change only means very little Macroscopic Young’s Modulus change. 展开更多
关键词 particle Contact MACROsCOPIC Young’s MODULUs ARRANGEMENTs of particle
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The basic blocks of the universe matter: Boltzmann fundamental particle and energy quanta of dark matter and dark energy 被引量:1
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作者 Murad Shibli Sohail Anwar 《Natural Science》 2011年第9期743-749,共7页
Recent astronomical NASA observations indicates that visible matter contributes only to about 4% of the universe total energy density, meanwhile, dark matter and dark energy contributes to 26% and 70% of the universe ... Recent astronomical NASA observations indicates that visible matter contributes only to about 4% of the universe total energy density, meanwhile, dark matter and dark energy contributes to 26% and 70% of the universe total energy, respectively, with an average density close to 10–26 kg/m3. This paper proposes an equation of state of dark energy and dark matter as one unified entity. This equation is derived based on the ideal gas equation, Boltzmann constant, Einstein energy-mass principle and based on the assumption that dark energy and dark matter behave as a perfect fluid. This analysis presents what could be the most fundamental particle and quanta of dark matter and dark energy. Considering NASA’s Cosmic Microwave Background Explorer (CMB) which estimated that the sky has an average temperature close to 2.7251 Kelvin, then the equivalent mass and energy of the proposed fundamental particle is determined. It is found that this candidate particle has an equivalent mass of 4.2141 × 10–40 Kg which is equivalent to 3.7674 × 10–23 J. Surprisingly, this value has the same order of Boltzmann constant KB = 1.38 ×10–23 J/K. This candidate particle could be the most fundamental and lightest particle in Nature and serves as the basic block of matter (quarks and gluons). Moreover, assuming a uniform space dark energy/dark matter density, then the critical temperature at which the dark matter has a unity entity per volume is determined as 34.983 × 1012 K. Analytically, it proposes that at this trillion temperature scale, the dark matter particles unified into a new quark-hydron particle. Finally, tentative experimental verification can be con ducted using the Relativistic Heavy Ion Collider (RHIC). 展开更多
关键词 DARK ENERGY DARK MATTER Equation of state BOLTZMANN CONsTANT Boltzamnn particles Einstine’s COsMOLOGICAL CONsTANT
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Elaboration and Characterization of a Hybrid Composite Material with Two Particles of the Same Size: Coco Shells and Palm Shells 被引量:1
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作者 Pierre Marcel Anicet Noah Ebanda Fabien Betene +3 位作者 Suzie Viviane Obame Beassoum Allasra Martin Christian Bindjeme Ateba Atangana 《Open Journal of Composite Materials》 2020年第4期77-91,共15页
This work aims to develop and characterize a hybrid composite material with two particles of the same size. As reinforcing particles, the hulls of palm nuts and coconut are chosen. Hybrid composite material composites... This work aims to develop and characterize a hybrid composite material with two particles of the same size. As reinforcing particles, the hulls of palm nuts and coconut are chosen. Hybrid composite material composites in the form of specimens were produced by molding at 10%, 20% and 30% mass fractions in various sizes (0.63<span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm, 1.25</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm and 2.5</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm). The samples were physically characterized (water absorption rate, moisture content, actual, theoretical and apparent density) and mechanical in 3-point flexion. The main results are: the highest and minimum water absorption rate are respectively 3.57% and 0.67% for respectively particle sizes 1.25</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm (sample P10C30) and 0.67% in the size of 0.63</span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm (sample P10C10). The moisture content varies from 0.64 to 7.14% respectively for the P20C20 (2.5 mm) and P10C30 (2.5 mm) samples. The maximum and minimum real density are 1340,518</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">Kg/m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> and 1055.981</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">Kg/m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">, for respectively the composites of particles sizes 1.25</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm (P20C10) and 0.63</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">mm (sample P20C20). The minimum real density is Its </span><span><span style="font-family:Verdana;">maximum theoretical density is 1194.949 Kg/m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> (for samples P20C10,</span></span><span style="font-family:Verdana;"> P10C10 and P30C10);however, the minimum is 1189.966 Kg/m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> (P10C20 and P20C20). The bulk density varies from 933.28</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">Kg/m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> to 1176.1</span></span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">Kg/m</span><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">, respectively, in sizes from 2.5</span></span><span style="font-family:;" "=""> </span><span style="font-family:Verdana;">mm (P10C30) to 0.63</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">mm (for P10C30). As for the mechanical characteristics, the Modulus of Elasticity (MOE) varies from 25.664 GPa to 25.759 GPa, respectively, the samples P10C10 (1.25 mm) and P10C20 (2.5 mm). The MOE values describe a parabola whose peak is reached when the palm shell loads are 20%, that is to say P20C10, whatever the particle size distribution. In resilience, samples with small particles are more resilient with a maximum value of 22.49 J/cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> and a minimum value of 4.45 J/cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> to verify the principles of Hall-Petch’s law.</span></span> 展开更多
关键词 Composite Hybrid Young’s Modulus POLYEsTER particles Hulls of Palm Nuts Hulls of Coconut
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Regeneration of Q-State PbS Particles in Langmuir-Blodgett Films
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作者 WU Yu-qing XU Wei-qing +2 位作者 ZHAO Bing TAO Yan-chun WU Ying and LI Bo-fu(Key Laboratory for Supramolecular Structure and Spectroscopy,Jilin University,Changchun,130023) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1996年第4期374-377,共4页
The regeneration procedure of Q-state PbS particles in lead arachidate(PbAr)Langmuir-Blodgett films have been studied by means of UV-vis absorption, FT-IR spectra and quartz crystal microbalance(QCM) measurements.The ... The regeneration procedure of Q-state PbS particles in lead arachidate(PbAr)Langmuir-Blodgett films have been studied by means of UV-vis absorption, FT-IR spectra and quartz crystal microbalance(QCM) measurements.The results showed that the mole fraction of PbS particles in LB films was increased by immersing PbScontaining ArH LB films in a Pb ̄(2+) buffer solution,followed by being reexposed to H_2S gas. 展开更多
关键词 s:Q-state Pbs particle Lead arachidate LB film UV-VIs FT-IR QCM.
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Probing the effect of Young's modulus on the plugging performance of micro-nano-scale dispersed particle gels
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作者 Zhi-Xuan Zhu Lin Li +4 位作者 Jia-Wei Liu Jia Chen Zhong-Zheng Xu Yi-Ning Wu Cai-Li Dai 《Petroleum Science》 SCIE CAS CSCD 2022年第2期688-696,共9页
The effect of mechanical strength of the dispersed particle gel(DPG)on its macro plugging performance is significant,however,little study has been reported.In this paper,DPG particles with different mechanical strengt... The effect of mechanical strength of the dispersed particle gel(DPG)on its macro plugging performance is significant,however,little study has been reported.In this paper,DPG particles with different mechanical strengths were obtained by mechanical shearing of bulk gels prepared with different formula.Young’s moduli of DPG particles on the micro and nano scales were measured by atomic force microscope for the first time.The mapping relationship among the formula of bulk gel,the Young’s moduli of the DPG particles and the final plugging performance were established.The results showed that when the Young’s moduli of the DPG particles increased from 82 to 328 Pa,the plugging rate increased significantly from 91.46%to 97.10%due to the distinctly enhanced stacking density and strength at this range.While when the Young’s moduli of the DPG particles surpassed 328 Pa,the further increase of plugging rate with the Young’s moduli of the DPG particles became insignificant.These results indicated that the improvement of plugging rate was more efficient by adjusting the Young’s moduli of the DPG particles within certain ranges,providing guidance for improving the macroscopic application properties of DPG systems in reservoir heterogeneity regulation. 展开更多
关键词 Dispersed particle gel Mechanical strength Young’s modulus Atomic force microscope Plugging performance
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A Hybrid Particle Swarm Optimization to Forecast Implied Volatility Risk
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作者 Kais Tissaoui Sahbi Boubaker +2 位作者 Waleed Saud Alghassab Taha Zaghdoudi Jamel Azibi 《Computers, Materials & Continua》 SCIE EI 2022年第11期4291-4309,共19页
The application of optimization methods to prediction issues is a continually exploring field.In line with this,this paper investigates the connectedness between the infected cases of COVID-19 and US fear index from a... The application of optimization methods to prediction issues is a continually exploring field.In line with this,this paper investigates the connectedness between the infected cases of COVID-19 and US fear index from a forecasting perspective.The complex characteristics of implied volatility risk index such as non-linearity structure,time-varying and nonstationarity motivate us to apply a nonlinear polynomial Hammerstein model with known structure and unknown parameters.We use the Hybrid Particle Swarm Optimization(HPSO)tool to identify the model parameters of nonlinear polynomial Hammerstein model.Findings indicate that,following a nonlinear polynomial behaviour cascaded to an autoregressive with exogenous input(ARX)behaviour,the fear index in US financial market is significantly affected by COVID-19-infected cases in the US,COVID-19-infected cases in the world and COVID-19-infected cases in China,respectively.Statistical performance indicators provided by the developed models show that COVID-19-infected cases in the US are particularly powerful in predicting the Cboe volatility index compared to COVID-19-infected cases in the world and China(MAPE(2.1013%);R2(91.78%)and RMSE(0.6363 percentage points)).The proposed approaches have also shown good convergence characteristics and accurate fits of the data. 展开更多
关键词 Forecasting Cboe’s volatility index COVID-19 pandemic nonlinear polynomial hammerstein model hybrid particle swarm optimization
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Many-body dissipative particle dynamics with energy conservation:temperature-dependent long-term attractive interaction
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作者 Jie LI Kaixuan ZHANG +3 位作者 Chensen LIN Lanlan XIAO Yang LIU Shuo CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2022年第4期497-506,共10页
Heat and mass transfer during the process of liquid droplet dynamic behaviors has attracted much attention in decades.At mesoscopic scale,numerical simulations of liquid droplets motion,such as impacting,sliding,and c... Heat and mass transfer during the process of liquid droplet dynamic behaviors has attracted much attention in decades.At mesoscopic scale,numerical simulations of liquid droplets motion,such as impacting,sliding,and coalescence,have been widely studied by using the particle-based method named many-body dissipative particle dynamics(MDPD).However,the detailed information on heat transfer needs further description.This paper develops a modified MDPD with energy conservation(MDPDE)by introducing a temperature-dependent long-term attractive interaction.By fitting or deriving the expressions of the strength of the attractive force,the exponent of the weight function in the dissipative force,and the mesoscopic heat friction coefficient about temperature,we calculate the viscosity,self-diffusivity,thermal conductivity,and surface tension,and obtain the Schmidt number Sc,the Prandtl number P r,and the Ohnesorge number Oh for 273 K to 373 K.The simulation data of MDPDE coincide well with the experimental data of water,indicating that our model can be used to simulate the dynamic behaviors of liquid water.Furthermore,we compare the equilibrium contact angle of droplets wetting on solid surfaces with that calculated from three interfacial tensions by MDPDE simulations.The coincident results not only stand for the validation of Young’s equation at mesoscale,but manifest the reliability of our MDPDE model and applicability to the cases with free surfaces.Our model can be extended to study the multiphase flow withcomplex heat and mass transfer. 展开更多
关键词 surface tension Young’s equation equilibrium contact angle many-body dissipative particle dynamics with energy conservation(MDPDE)
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Effects of Isospin on Pre-scission Particle Multiplicity of Heavy Systems and ItsExcitation Energy Dependence
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作者 YEWei CHENNa 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5期751-756,共6页
Isospin effects on particle emission of fissioning isobaric sources 202Fr, 202po, 202Tl and isotopic sources 189,202,212Po, and its dependence on the excitation energy are studied via Smoluchowski equations. It is sho... Isospin effects on particle emission of fissioning isobaric sources 202Fr, 202po, 202Tl and isotopic sources 189,202,212Po, and its dependence on the excitation energy are studied via Smoluchowski equations. It is shown that with increasing the isospin of fissioning systems, charged-particle emission is not sensitive to the strength of nuclear dissipation. In addition, we have found that increasing the excitation energy not only increases the influence of nuclear dissipation on particle emission but also greatly enhances the sensitivity of the emission of pre-scission neutrons or charged particles to the isospin of the system. Therefore, in order to extract dissipation strength more accurately by taking light particle multiplicities it is important to choose both a highly excited compound nucleus and a proper kind of particles for systems with different isospins. 展开更多
关键词 钫原子核 同位旋作用 多离子发射 激发能 分裂扩散模型 原子核物理学
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Determination of Photon and Elementary Particles Rest Masses Using Maxwell’s Equations and Generalized Potential Dependent Special Relativity
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作者 Abeer Mohammed Khairy Ahmed Mashair Ahmed Mohammed Yousif +5 位作者 Zainab Mustapha Kurawa Zoalnoon Ahmed Abeid Allah Saad Suhair Salih Makawy Mohammed Idriss Mohammed Mubarak Dirar Abd-Alla Sami Abdalla Elbadawi Mohamed 《Natural Science》 2020年第8期588-598,共11页
The nature and origin of the photon and elementary rest masses are some of the challeng-ing problems that physics face. The approaches used to solve these problems are complex and time-consuming. Specifically, the pho... The nature and origin of the photon and elementary rest masses are some of the challeng-ing problems that physics face. The approaches used to solve these problems are complex and time-consuming. Specifically, the photon rest mass pays attention to theoretical physi-cists. Many experimental works show that the photon rest mass is non zero. This problem can be solved using generalized potential dependent special relativity, which has been de-rived using simple arguments, and Maxwell’s equations, besides the conventional Einstein energy-momentum relation. The results obtained show that the rest mass of photons and elementary particles are strongly dependent on the vacuum energy and a universal con-stant. This result conforms with the models that predict time decaying vacuum energy as-sociated with production of smaller rest mass particles followed by larger masses. The two potential dependent mass expressions conform with the cosmological models that suggest the photon is generated first by assuming the universe consisting of total constant vacuum with decaying cosmological part and mass generating part. Using Maxwell’s equations, beside plank and De Broglie hypothesis together with special relativity energy-momentum relation the photon rest mass is estimated. It was shown that the photon rest mass is ex-tremely small compared to the electron mass. 展开更多
关键词 PHOTON Elementary particles Maxwell’s Equations Potential Dependent special Relativity Vacuum Energy
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The Criteria for Reducing Centrally Restricted Three-Body Problem to Two-Body Problem
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作者 Bijay Kumar Sharma 《International Journal of Astronomy and Astrophysics》 2024年第1期1-19,共19页
Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubatio... Our Solar System contains eight planets and their respective natural satellites excepting the inner two planets Mercury and Venus. A satellite hosted by a given Planet is well protected by the gravitational pertubation of much heavier planets such as Jupiter and Saturn if the natural satellite lies deep inside the respective host Planet Hill sphere. Each planet has a Hill radius a<sub>H</sub> and planet mean radius R<sub>P </sub>and the ratio R<sub>1</sub>=R<sub>P</sub>/a<sub>H</sub>. Under very low R<sub>1 </sub>(less than 0.006) the approximation of CRTBP (centrally restricted three-body problem) to two-body problem is valid and planet has spacious Hill lobe to capture a satellite and retain it. This ensures a high probability of capture of natural satellite by the given planet and Sun’s perturbation on Planet-Satellite binary can be neglected. This is the case with Earth, Mars, Jupiter, Saturn, Neptune and Uranus. But Mercury and Venus has R<sub>1</sub>=R<sub>P</sub>/a<sub>H</sub> =0.01 and 5.9862 × 10<sup>-3</sup> respectively hence they have no satellites. There is a limit to the dimension of the captured body. It must be a much smaller body both dimensionally as well masswise. The qantitative limit is a subject of an independent study. 展开更多
关键词 Hill’s Radius Two-Body Problem Fixed-Point solution Lagrange Points Earth-Moon-Test particle CRTBP
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Mineral Particles Found on the Hairs of Holy Maria-Magdalena Studied by Scanning Electron Microscopy and Elemental Analysis
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作者 Gérard Lucotte 《Open Journal of Applied Sciences》 2020年第3期41-59,共19页
The presumed hairs of Holy Maria-Magdalena are studied here for mineral particles found on their surfaces, by the techniques of scanning electron microscopy coupled with energy dispersive X-ray. Exploration by these t... The presumed hairs of Holy Maria-Magdalena are studied here for mineral particles found on their surfaces, by the techniques of scanning electron microscopy coupled with energy dispersive X-ray. Exploration by these techniques of the hair surfaces allows us to observe and study some marble fragments that can originate from the walls of the sarcophagus in which Maria-Magdalena’s remains were kept. These new findings support the authenticity of the hair as traditionally reported in the French “tradition des Saints de Provence”. 展开更多
关键词 Maria-Magdalena’s HAIR scanning Electron Microscopy Energy Disper-sive X-Ray MARBLE FRAGMENTs MINERAL particles
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Gravitational Space-Time Curve Generation via Accelerated Charged Particles
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作者 Edward A. Walker 《Journal of Modern Physics》 2016年第9期863-874,共12页
A force with an acceleration that is equal to multiples greater than the speed of light per unit time is exerted on a cloud of charged particles. The particles are resultantly accelerated to within an infinitesimal fr... A force with an acceleration that is equal to multiples greater than the speed of light per unit time is exerted on a cloud of charged particles. The particles are resultantly accelerated to within an infinitesimal fraction of the speed of light. As the force or acceleration increases, the particles’ velocity asymptotically approaches but never achieves the speed of light obeying relativity. The asymptotic increase in the particles’ velocity toward the speed of light as acceleration increasingly surpasses the speed of light per unit time does not compensate for the momentum value produced on the particles at sub-light velocities. Hence, the particles’ inertial mass value must increase as acceleration increases. This increase in the particles’ inertial mass as the particles are accelerated produce a gravitational field which is believed to occur in the oscillation of quarks achieving velocities close to the speed of light. The increased inertial mass of the density of accelerated charged particles becomes the source mass (or Big “M”) in Newton’s equation for gravitational force. This implies that a space-time curve is generated by the accelerated particles. Thus, it is shown that the acceleration number (or multiple of the speed of light greater than 1 per unit of time) and the number of charged particles in the cloud density are surjectively mapped to points on a differential manifold or space-time curved surface. Two aspects of Einstein’s field equations are used to describe the correspondence between the gravitational field produced by the accelerated particles and the resultant space-time curve. The two aspects are the Schwarzchild metric and the stress energy tensor. Lastly, the possibility of producing a sufficient acceleration or electromagnetic force on the charged particles to produce a gravitational field is shown through the Lorentz force equation. Moreover, it is shown that a sufficient voltage can be generated to produce an acceleration/force on the particles that is multiples greater than the speed of light per unit time thereby generating gravity. 展开更多
关键词 Charged particles Accelerated particles Inertial Mass Gravitational Force Einstein’s Field Equations space-Time Manifold schwardchild Metric stress Energy Tensor surjective Mapping Lorentz Force
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The Natural Law of Transition of a Charged Particle into a Compound State under the Action of an Electroscalar Field
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作者 Oleg Antonovich Zaimidoroga 《Journal of Modern Physics》 2016年第15期2188-2204,共17页
This article is the continuation of article [1] where the experimental facts of observation of the electroscalar radiation in the spectrum of the Sun have been presented [2]. This radiation comes into the world having... This article is the continuation of article [1] where the experimental facts of observation of the electroscalar radiation in the spectrum of the Sun have been presented [2]. This radiation comes into the world having a long wavelength, being longitudinal and extraordinarily penetrating. In accordance with the principle of least action, the Lagrangian of the electroscalar field and the tensor of energy-moment are determined using the variation the potential and coordinates. The equation of motion the charged particle in electroscalar field is determined and the energy of particle has the negative sign with respect to the mechanical energy of particle and the energy of electromagnetic field. So, this is decreasing the electrical potential of particle during the propagation. The electroscalar energy of charged particle and field’s force acting on the particle during their motion change the particle’s electrical status which, in its turn, may trigger the transition of the particle into a compound state during interaction with any object. Due to the continuity this process can lead the particle to the state which enters into a compound state with a negative energy for a different particle’s velocity. This state is the physical vacuum’s state. Analysis of the solar spectrum demonstrates that scattering and absorption of electroscalar wave go on the cavities of solids. The spreading out of electroscalar field obeys to the law of plane wave and the transfer the energy and information can occur in vacuum and any medium. 展开更多
关键词 Equation of Motion of Electroscalar Field Tensor Energy-Moment of Electroscalar Field Natural Law of particle’s Transition into a Compound state Physical Vacuum
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Background Simulation of a Fission Fragment Chamber in the Experiment of ^(209)Bi(e,e’K^+)^(209)_ ΛPb
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作者 宋玉收 刘辉兰 +2 位作者 席印印 颜强 胡碧涛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第5期415-418,共4页
An experiment for measuring the hyperon-related fission rate was carried out with the reaction 209^Bi(e, e'K^+)209^hPb at the Thomas Jefferson National Laboratory (Jlab). In the experiment, the performance of th... An experiment for measuring the hyperon-related fission rate was carried out with the reaction 209^Bi(e, e'K^+)209^hPb at the Thomas Jefferson National Laboratory (Jlab). In the experiment, the performance of the fission fragment detector (FFD) was dramaticlly crashed by the background particles in comparison with that during the test without beam. The scattering of the high intensity (500 nA) primary electrons was the dominant cause. Using the GEANT4 toolkit, this report simulates the experimental situation of the target chamber in which the FFD was located. The simulation results indicate that the background particles were dominantly (~ electrons, and protons and alpha particles were the important heavy background particles. The performance of the multi-wire proportional chambers (MWPCs) depends not only on the background-particle intensity but also the current density, which was also given by the simulation code. Furthermore, the measures to suppress the background particles were also investigated with the simulation code. 展开更多
关键词 fission fragments HYPERON background particles Monte Carlo simulation
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基于PSO-GRNN和D-S证据理论的电网分区故障诊断 被引量:4
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作者 邹红波 宋璐 +2 位作者 张馨煜 段治丰 宋家乐 《智慧电力》 北大核心 2023年第3期25-30,45,共7页
针对大电网中保护和断路器误动、拒动、信息丢失等不确定的电网故障信息以及现有电网分区方法的不足,提出了基于粒子群优化广义回归神经网络(PSO-GRNN)和D-S证据理论的电网分区故障诊断方法。首先,通过改进图形分割法将大电网划分为相... 针对大电网中保护和断路器误动、拒动、信息丢失等不确定的电网故障信息以及现有电网分区方法的不足,提出了基于粒子群优化广义回归神经网络(PSO-GRNN)和D-S证据理论的电网分区故障诊断方法。首先,通过改进图形分割法将大电网划分为相互重叠的不同区域,降低故障诊断难度。然后在各个区域建立PSOGRNN诊断模块,根据故障警报信息,并行完成各自的故障诊断任务。最后,采用D-S证据理论对相邻区域的重叠区域进行分析,以实现对重叠区域的综合故障诊断。仿真结果表明,该方法能有效识别非重叠区域和重叠区域的故障,容错能力强,诊断准确率高。 展开更多
关键词 电网分区 故障诊断 改进图形分割法 粒子群算法 广义回归神经网络 D-s证据理论
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