The pseudo-rapidity distributions of the charged particles produced in the asymmetric collision systems p+Al,p+Au and ^(3)He+Au at√S_(NN)=200 GeV GeV are evaluated in the framework of a fireball model with Tsallis th...The pseudo-rapidity distributions of the charged particles produced in the asymmetric collision systems p+Al,p+Au and ^(3)He+Au at√S_(NN)=200 GeV GeV are evaluated in the framework of a fireball model with Tsallis thermodynamics.The fireball model assumes that the experimentally measured particles are produced by fireballs following the Tsallis distribution and it can effectively describe the experimental data.Our results as well as previous results for d+Au collisions at√S_(NN)=200 GeV GeV and p+Pb collisions at√S_(NN)=5.02 TeV TeV validate that the fireball model based on Tsallis thermodynamics can provide a universal framework for pseudo-rapidity distribution of the charged particles produced in asymmetric collision systems.We predict the centrality dependence of the total charged particle multiplicity in the p+Al,p+Au and 3He+Au collisions.Additionally,the dependences of the fireball model parameters(y_(0a),y_(0A),σ_(a) and σ_(A))on the centrality and system size are studied.展开更多
Exposing waxy oils to an electric field may significantly improve their cold flowability.Our previous study has shown that interfacial polarization,i.e.,charged particle accumulation on the wax particle surface,is the...Exposing waxy oils to an electric field may significantly improve their cold flowability.Our previous study has shown that interfacial polarization,i.e.,charged particle accumulation on the wax particle surface,is the primary mechanism of the electrorheological behavior of waxy oils.However,the way that charged particles interact with wax particles under an electric field remains unknown.In this study,we found no viscosity and impedance change for two waxy crude oils after their exposure to a high-voltage electric field.However,the yield stresses were reduced obviously.We thus proposed that the collision of colloidal particles such as resins and asphaltenes with the wax particles could be an essential mechanism that the wax particle structure was weakened.To verify this hypothesis,a series of ad hoc experiments were carried out,i.e.,by performing electrorheological tests on model waxy oils containing additives removable under an electric field,including electrically-neutral colloidal particles(Fe3O4),charged colloidal particles(resins),and oil-soluble electrolyte(C22H14CoO4),respectively,and demonstrated that upon application of a high-voltage electric field,charged particles in a waxy oil may move and thus collide with wax particles,and consequently adhere to the wax particle surface.The particle collision results in damage to the wax particle network,and the electrostatic repulsion arising from the adhesion of the charged particle on the wax particle diminishes attraction between wax particles.This study clarifies the process of interfacial polarization.展开更多
<strong>Background: </strong>Since the beginning of the global COVID-19 pandemic, several studies have been carried out to investigate its spread, with a wide range of factors to understand the influence o...<strong>Background: </strong>Since the beginning of the global COVID-19 pandemic, several studies have been carried out to investigate its spread, with a wide range of factors to understand the influence of the factors that contribute to its spread and to reduce the ongoing threat of COVID-19 pandemic. <strong>Methods: </strong>In this study, the relationships between the Earth’s electric field and cosmic ray charged particles of different energy ranges and the daily confirmed COVID-19 infections in Riyadh, Saudi Arabia have been investigated using non-parametric statistical tests. The data covered the period between 3 April 2020 and 1<sup>st </sup>August 2021 and were obtained from the King Abdulaziz City for Science and Technology (KACST) CARPET detector, Riyadh, Saudi Arabia. The electric fields data were obtained from electric field monitor (EFM) deployed on the rooftop of the KACST laboratory. The data of the daily COVID-19 cases were obtained from the official webpage of the Saudi Arabian Ministry of Health (MOH). <strong>Results: </strong>The results revealed that that the number of COVID-19 cases is correlated with cosmic ray charged particles and anti-correlated with the Earth’s electric field. <strong>Conclusion: </strong>While the exact mechanism explaining the influence of Earth’s electric field and cosmic rays variations on the reported number of COVID-19 cases is not yet established, the results presented in this study can add additional knowledge to our understanding of the effects of additional factors on influenza activities.展开更多
In the context of unified hydrodynamics, we discuss the pseudorapidity distributions of the charged particles produced in Au-Au and Cu-Cu collisions at the low RHIC energies of √SNN = 19.6 and 22.4 GeV, respectively....In the context of unified hydrodynamics, we discuss the pseudorapidity distributions of the charged particles produced in Au-Au and Cu-Cu collisions at the low RHIC energies of √SNN = 19.6 and 22.4 GeV, respectively. It is found that the unified hydrodynamics alone can give a good description to the experimental measurements. This is different from the collisions at the maximum RHIC energy of √SNN = 200 GeV or at LHC energy of √SNN= 2.76 TeV, in which the leading particles must be taken into account so that we can properly explain the experimental observations.展开更多
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
Governing conservation equations for energy, momentum, mass and charge were deduced. Based upon these equations and the Saha equation, the particle density, temperature and pressure of the channel initiated by underwa...Governing conservation equations for energy, momentum, mass and charge were deduced. Based upon these equations and the Saha equation, the particle density, temperature and pressure of the channel initiated by underwater pulsed discharge, are simulated. Influence of temperature and pressure on particles density is also analyzed. Some of the simulation results are in an agreement with experimental results. The results will be helpful in further understanding of the formation mechanism of underwater pulsed discharge plasma.展开更多
Many multicomponent concentrated solid solution alloys(CSAs),including high-entropy alloys(HEAs),exhibit improved radiation resistance and enhanced structural stability in harsh environments.To study and assess irradi...Many multicomponent concentrated solid solution alloys(CSAs),including high-entropy alloys(HEAs),exhibit improved radiation resistance and enhanced structural stability in harsh environments.To study and assess irradiation resistance of nuclear materials,energetic ion and electron beams are commonly used to create displacement damage.Moreover,charged particles of ions,electrons,and positrons are unique tools to create and characterize radiation effects.Ion beam analysis(e.g.,Rutherford backscattering spectrometry,nuclear reaction analysis,and time-of-flight elastic recoil detection analysis),electron microscopy techniques(e.g.,transmission or scanning electron microscopy,and electron diffraction),and positron annihilation spectroscopy have been applied to characterize irradiated CSAs or HEAs to understand defect formation and evolution together with chemical and microstructural information.Their distinctive analyzing power and some perspectives in these techniques are reviewed.In developing structural alloys desirable for applications in advanced reactors,neutron exposure is a critical test but the limitation in achievable high damage levels is,however,a bottleneck.Ion irradiation is often used as a surrogate for neutron irradiation,and the associated reduced transmutations and higher displacements per atom(dpa)rates are desirable for materials research.Nevertheless,cautions need to be taken when relying on ion irradiation results for reactor evaluations.Literature on differences between ions and neutrons is briefly reviewed.In addition,the links to bridge the current advances on fundamental understandings to reactor applications are discussed to lay the groundwork between neutrons and ions for radiation effects studies.展开更多
This paper investigated average cluster sizes (ACS) and cluster size distributions (CSD) at different shear rates by Brownian dynamics in non-, bi-, and uni-polar systems with partly charged superfine particles, T...This paper investigated average cluster sizes (ACS) and cluster size distributions (CSD) at different shear rates by Brownian dynamics in non-, bi-, and uni-polar systems with partly charged superfine particles, The investigation indicates that clusters in non- polar systems are the weakest and easiest to be damaged by increasing shear stresses; charged particles play important and different roles: in bi-polar system, it intends to strengthen clusters to some extent provided that the sign-like ions homogeneously arranged; in uni-polar system charged particles cracked the clusters into smaller ones, but the small clusters are strong to stand with larger shear stress. The relationship between ACS and shear rates follows power law with exponents in a range 0.18-0.28, these values are in a good agreement with experiment range but at the lower limit compared with other systems of non-metallic cluster particles.展开更多
In order to study the relationship between the non-spherical atmospheric charged particles and satellite-ground quantum links attenuation. The relationship among the particle concentration, equivalent radius, charge d...In order to study the relationship between the non-spherical atmospheric charged particles and satellite-ground quantum links attenuation. The relationship among the particle concentration, equivalent radius, charge density of the charged particle, the attenuation coefficient and entanglement of the satellite-ground quantum link can be established first according to the extinction cross section and spectral distribution function of the non-spherical atmospheric charged particles. The quantitative relationship between atmospheric visibility and communication fidelity of satellite-ground quantum link were analyzed then. Simulation results show that the ellipsoid, Chebyshev atmospheric charged particle influences on attenuation of the satellite-ground quantum link increase progressively. When the equivalent particle radius is 0.2 gm and the particle concentration is 50 μg/m^3, the attenuation coefficient and entanglement of the satellite-ground quantum link is 9.21 dB/km, 11.46 dB/km and 0.453, 0.421 respectively; When the atmospheric visibility reduces from 8 km to 2 kin, the communication fidelity of satellite-ground quantum link decreases from 0.52 to 0.08. It is shown that the non-spherical atmospheric charged particles and atmospheric visibility influence greatly on the performance of the satellite-ground quantum link communication system. Therefore, it is necessary to adjust the parameters of the quantum-satellite communication system according to the visibility values of the atmosphere and the shapes of the charged particles in the atmosphere to improve reliability of the satellite-ground quantum link.展开更多
We investigate the effects of jet production on the following parameters: pseudorapidity, transverse momentum and transverse mass distributions of secondary charged particles produced in pp-collisions at 1.8 Te V,usi...We investigate the effects of jet production on the following parameters: pseudorapidity, transverse momentum and transverse mass distributions of secondary charged particles produced in pp-collisions at 1.8 Te V,using the HIJING code. These distributions are analyzed for the whole range and for six selected regions of the polar angle as a function of the different number of jets. The obtained simulation results for these parameters are interpreted and discussed in connection to the increase observed in the multiplicity of secondary charged particles as a result of its multi-jet dependence, and are also discussed in comparison with the experimental results from the CDF Collaboration.展开更多
The spatiotemporal evolutions of a one-dimensional collisionless decaying plasma bounded by two electrodes with an externally applied electrostatic field are studied by theoretical analyses and particle-in-cell(PIC)si...The spatiotemporal evolutions of a one-dimensional collisionless decaying plasma bounded by two electrodes with an externally applied electrostatic field are studied by theoretical analyses and particle-in-cell(PIC)simulations with the ion extraction process in a laser-induced plasma as the major research background.Based on the theoretical analyses,the transport process of the charged particles including electrons and ions can be divided into three stages:electron oscillation and ion matrix sheath extraction stage,sheath expansion and ion rarefaction wave propagation stage and the plasma collapse stage,and the corresponding criterion for each stage is also presented.Consequently,a complete analytical model is established for describing the ion extraction flux at each stage during the decaying of the laser-induced plasmas under an electrostatic field,which is also validated by the PIC modeling results.Based on this analytical model,influences of the key physical parameters,including the initial electron temperature and number density,plasma width and the externally applied electric voltage,on the ratio of the extracted ions are predicted.The calculated results show that a higher applied electric potential,smaller initial plasma number density and plasma width lead to a higher ratio of the extracted ions during the first stage;while in this stage,the initial electron temperature shows little effect on it.Meanwhile,more ions will be extracted before the plasma collapse once a higher electric potential is applied.The theoretical model presented in this paper is helpful not only for a deep understanding to the charged particle transport mechanisms for a bounded decaying plasma under an applied electrostatic field,but also for an optimization of the ion extraction process in practical applications.展开更多
Dispersion and surface deposition of charged particles by gas-solids jets in confined chambers are constantly encountered in many industrial applications such as in electrostatic precipitation and dry powder coating p...Dispersion and surface deposition of charged particles by gas-solids jets in confined chambers are constantly encountered in many industrial applications such as in electrostatic precipitation and dry powder coating processes. Understanding and control of flow patterns and trajectories of charged particles are important to the optimal design and operation of such devices. In this study, modeling of flow fields and particle trajectories of dilute gas-solid two-phase flows with charged particles in confined chambers is performed. The dilute gas-solid two-phase flows are simulated by use of a hybrid Eulerian-Lagrangian approach with the one-way coupling between the gaseous phase and particle phase. The space charge distribution is included as a source term in equations of motion or Lagrangian equation of charged particles, which in turn depends on the particle trajectories that determine the space charge distribution. Our modeling predictions suggested that the electrostatic charge plays a significant role in particle radial dispersion. Effect of voltage has limited influence on particle trajectories however it can have a big impact on the residence time. Cone angle has a significant effect on the structure of flow field. For cone with a larger cone angle (typically over 15°), there will be a flow separation along the side wall near the flow entrance region. By comparing with the conical chamber, the cylindrical chamber has a big vortex and three smaller vortexes in the lower part of the chamber, which would complicate the particle dispersion with or without the coupling of charging.展开更多
Time evolution of ionospheric D-region plasmas including the perturbations of electrons and charged aerosol particles is investigated under the conditions of polar mesosphere summer echoes (PMSE). It is shown that t...Time evolution of ionospheric D-region plasmas including the perturbations of electrons and charged aerosol particles is investigated under the conditions of polar mesosphere summer echoes (PMSE). It is shown that the time scale of decay of the electron density is in the order of an hour under typical PMSE conditions, in the majority of cases, the electron density is anticorrelated to the ion density, except that the radius of aerosol particles is greater than 50 nm. Also, the evolutions under varied parameters, such as the amplitude and width of perturbation, the aerosol particle radius, and the altitude of the PMSE occurrence are investigated. The obtained results are useful for interpreting the experimental observations.展开更多
The revised Landau hydrodynamic model is used to discuss the pseudorapidity distributions of the produced charged particles in Au+Au and Cu+Cu collisions at energies of s √SNN=19.6 and 22.4 GeV respectively at the ...The revised Landau hydrodynamic model is used to discuss the pseudorapidity distributions of the produced charged particles in Au+Au and Cu+Cu collisions at energies of s √SNN=19.6 and 22.4 GeV respectively at the BNL Relativistic Heavy Ion Collider. It is found that the revised Landau hydrodynamic model alone can give a good description of the experimental measurements. This is different from the result with the same collisions but at the maximum energy of√SNN=200 GeV, where in addition to the revised Landau hydrodynamic model, the effects of leading particles have to be taken into account in order to explain the experimental observations. This can be attributed to the different degrees of transparency of participants at the different incident energies.展开更多
In this paper, we describe a possible method for predicting the earthquakes, which is based on simultaneous recording of the intensity of fluxes of neutrons and charged particles by detectors, commonly used in nuclear...In this paper, we describe a possible method for predicting the earthquakes, which is based on simultaneous recording of the intensity of fluxes of neutrons and charged particles by detectors, commonly used in nuclear physics. These low-energy particles originate from radioactive nuclear processes in the Earth's crust. The variations in the particle flux intensity can be the precursor of the earth- quake. A description is given of an electronic installation that records the fluxes of charged particles in the radial direction, which are a possible response to the accumulated tectonic stresses in the Earth's crust. The obtained results showed an increase in the intensity of the fluxes for 10 or more hours before the occurrence of the earthquake. The previous version of the installation was able to indicate for the possibility of an earthquake (Maksudov et al. in Instrum Exp Tech 58:130-131, 2015), but did not give information about the direction of the epicenter location. In this regard, the installation was modified by adding eight directional detectors. With the upgraded setup, we have received both the predictive signals, and signals determining the directions of the location of the forthcoming earthquake, starting 2-3 days before its origin.展开更多
Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of l...Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the targets.The reaction channels,including sequential and simultaneous emission processes,are analyzed in detail.Taking the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted particles.The optical potential parameters of the proton are obtained by fitting the elastic scattering differential cross-sections.The calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing angles.Simultaneously,the mixed double differential cross-sections of^(3) He andαare in good agreement with the measurements.The agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction processes.Based on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles.展开更多
The transition radiation of a charged particle crossing the interface of two media having a monatomic impurity layer is investigated. It is shown that at sliding angles of incidence of a particle on the boundary of th...The transition radiation of a charged particle crossing the interface of two media having a monatomic impurity layer is investigated. It is shown that at sliding angles of incidence of a particle on the boundary of the media, the transition radiation is mainly determined by the properties of the surface layer. The possibility of using transition radiation to study the surface of substances is discussed. In addition, due to the hard radiation present in space, this research may be important for the use of light monoatomic layers as a material for satellite antennas, “solar sails” and cover layers in a future space (interstellar) mission.展开更多
In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarl...In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarly charged and coagulated in the same alternating electric field simultaneously. The silica flour with 2 fun mass median diameter and the smoke from burning wood powder were used as test aerosol. The comparison experimental results have shown that when the mean electric field is 4 kV/cm the collection efficiency of the new electrostatic agglomerator was 98.2% for silica flour and 67.4% for wood powder smoke, Under the same experimental condition. the collection efficiency of the electrostatic agglomerator with three zones was 97.4% for collecting silica flour and the collection efficiency of the electrostatic precipitator was 56.3% for wood powder smoke.展开更多
Objective The changes in serum adipokines and cytokines related to oxidative stress were examined during 3 months ‘Off to On’ and ‘On to Off’ periods using negatively charged particle-dominant indoor air condition...Objective The changes in serum adipokines and cytokines related to oxidative stress were examined during 3 months ‘Off to On’ and ‘On to Off’ periods using negatively charged particle-dominant indoor air conditions(NCPDIAC).Methods Seven volunteers participated in the study,which included ‘OFF to 3 months ON’ periods(ON trials) for a total of 16 times,and ‘ON to 3 months OFF’(OFF trials) periods for a total of 13 times.Results With the exception of one case,serum amyloid A(SAA) levels decreased significantly during the ON trials.Conclusion Considering that SAA is an acute phase reactive protein such as C reactive protein(CRP),this observed decrease might indicate the prevention of cardiovascular and atherosclerotic changes,since an increase in high-sensitive CRP is associated with the subsequent detection of these events.展开更多
Extending Parikh's semi-classical quantum tunnelling model, this paper has studied the Hawking radiation of the charged particle via tunnelling from the horizon of the axisymmetric Sen black hole. Different from the ...Extending Parikh's semi-classical quantum tunnelling model, this paper has studied the Hawking radiation of the charged particle via tunnelling from the horizon of the axisymmetric Sen black hole. Different from the uncharged massless particle, the geodesics of the charged massive particle tunnelling from the horizon is not light-like. The derived result supports Parikh's opinion and provides a correct modification to Hawking strictly thermal spectrum developed by the fixed background space-time and not considering the energy conservation and the self-gravitation interaction.展开更多
基金This work was supported in part by the National Natural Science Foundation of China(Nos.11905120,11947416)the Natural Science Foundation of Sichuan Province(No.2023NSFSC1322)+2 种基金the Natural Science Basic Research Plan in Shaanxi Province of China(No.2023-JC-YB-012)the United States Department of Energy(#DE-FG02-93ER40773)the NNSA(No.DENA0003841(CENTAUR)).
文摘The pseudo-rapidity distributions of the charged particles produced in the asymmetric collision systems p+Al,p+Au and ^(3)He+Au at√S_(NN)=200 GeV GeV are evaluated in the framework of a fireball model with Tsallis thermodynamics.The fireball model assumes that the experimentally measured particles are produced by fireballs following the Tsallis distribution and it can effectively describe the experimental data.Our results as well as previous results for d+Au collisions at√S_(NN)=200 GeV GeV and p+Pb collisions at√S_(NN)=5.02 TeV TeV validate that the fireball model based on Tsallis thermodynamics can provide a universal framework for pseudo-rapidity distribution of the charged particles produced in asymmetric collision systems.We predict the centrality dependence of the total charged particle multiplicity in the p+Al,p+Au and 3He+Au collisions.Additionally,the dependences of the fireball model parameters(y_(0a),y_(0A),σ_(a) and σ_(A))on the centrality and system size are studied.
基金financial support from the National Natural Science Foundation of China(No.52174066,No.51534007).
文摘Exposing waxy oils to an electric field may significantly improve their cold flowability.Our previous study has shown that interfacial polarization,i.e.,charged particle accumulation on the wax particle surface,is the primary mechanism of the electrorheological behavior of waxy oils.However,the way that charged particles interact with wax particles under an electric field remains unknown.In this study,we found no viscosity and impedance change for two waxy crude oils after their exposure to a high-voltage electric field.However,the yield stresses were reduced obviously.We thus proposed that the collision of colloidal particles such as resins and asphaltenes with the wax particles could be an essential mechanism that the wax particle structure was weakened.To verify this hypothesis,a series of ad hoc experiments were carried out,i.e.,by performing electrorheological tests on model waxy oils containing additives removable under an electric field,including electrically-neutral colloidal particles(Fe3O4),charged colloidal particles(resins),and oil-soluble electrolyte(C22H14CoO4),respectively,and demonstrated that upon application of a high-voltage electric field,charged particles in a waxy oil may move and thus collide with wax particles,and consequently adhere to the wax particle surface.The particle collision results in damage to the wax particle network,and the electrostatic repulsion arising from the adhesion of the charged particle on the wax particle diminishes attraction between wax particles.This study clarifies the process of interfacial polarization.
文摘<strong>Background: </strong>Since the beginning of the global COVID-19 pandemic, several studies have been carried out to investigate its spread, with a wide range of factors to understand the influence of the factors that contribute to its spread and to reduce the ongoing threat of COVID-19 pandemic. <strong>Methods: </strong>In this study, the relationships between the Earth’s electric field and cosmic ray charged particles of different energy ranges and the daily confirmed COVID-19 infections in Riyadh, Saudi Arabia have been investigated using non-parametric statistical tests. The data covered the period between 3 April 2020 and 1<sup>st </sup>August 2021 and were obtained from the King Abdulaziz City for Science and Technology (KACST) CARPET detector, Riyadh, Saudi Arabia. The electric fields data were obtained from electric field monitor (EFM) deployed on the rooftop of the KACST laboratory. The data of the daily COVID-19 cases were obtained from the official webpage of the Saudi Arabian Ministry of Health (MOH). <strong>Results: </strong>The results revealed that that the number of COVID-19 cases is correlated with cosmic ray charged particles and anti-correlated with the Earth’s electric field. <strong>Conclusion: </strong>While the exact mechanism explaining the influence of Earth’s electric field and cosmic rays variations on the reported number of COVID-19 cases is not yet established, the results presented in this study can add additional knowledge to our understanding of the effects of additional factors on influenza activities.
基金Supported by the Shanghai Key Lab of Modern Optical System
文摘In the context of unified hydrodynamics, we discuss the pseudorapidity distributions of the charged particles produced in Au-Au and Cu-Cu collisions at the low RHIC energies of √SNN = 19.6 and 22.4 GeV, respectively. It is found that the unified hydrodynamics alone can give a good description to the experimental measurements. This is different from the collisions at the maximum RHIC energy of √SNN = 200 GeV or at LHC energy of √SNN= 2.76 TeV, in which the leading particles must be taken into account so that we can properly explain the experimental observations.
文摘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.
基金supported by National Natural Science Foundation of Chinathe Research Fund for the Doctoral Program of Higher Education of China (No.20040214003)the Science Fund of Provincial Department of Education of China (No.11521243)
文摘Governing conservation equations for energy, momentum, mass and charge were deduced. Based upon these equations and the Saha equation, the particle density, temperature and pressure of the channel initiated by underwater pulsed discharge, are simulated. Influence of temperature and pressure on particles density is also analyzed. Some of the simulation results are in an agreement with experimental results. The results will be helpful in further understanding of the formation mechanism of underwater pulsed discharge plasma.
基金supported as part of Energy Dissipation to Defect Evolution(EDDE)an Energy Frontier Research Center funded by the U.S.Department of Energy,Office of Science,Basic Energy Sciences,under contract number DE-AC05-00OR22725.
文摘Many multicomponent concentrated solid solution alloys(CSAs),including high-entropy alloys(HEAs),exhibit improved radiation resistance and enhanced structural stability in harsh environments.To study and assess irradiation resistance of nuclear materials,energetic ion and electron beams are commonly used to create displacement damage.Moreover,charged particles of ions,electrons,and positrons are unique tools to create and characterize radiation effects.Ion beam analysis(e.g.,Rutherford backscattering spectrometry,nuclear reaction analysis,and time-of-flight elastic recoil detection analysis),electron microscopy techniques(e.g.,transmission or scanning electron microscopy,and electron diffraction),and positron annihilation spectroscopy have been applied to characterize irradiated CSAs or HEAs to understand defect formation and evolution together with chemical and microstructural information.Their distinctive analyzing power and some perspectives in these techniques are reviewed.In developing structural alloys desirable for applications in advanced reactors,neutron exposure is a critical test but the limitation in achievable high damage levels is,however,a bottleneck.Ion irradiation is often used as a surrogate for neutron irradiation,and the associated reduced transmutations and higher displacements per atom(dpa)rates are desirable for materials research.Nevertheless,cautions need to be taken when relying on ion irradiation results for reactor evaluations.Literature on differences between ions and neutrons is briefly reviewed.In addition,the links to bridge the current advances on fundamental understandings to reactor applications are discussed to lay the groundwork between neutrons and ions for radiation effects studies.
基金supported by the National Natural Science Foundation of China(No.50474037)The Natural Science Funds(No.KB2006078)in Jiangsu Province of China.
文摘This paper investigated average cluster sizes (ACS) and cluster size distributions (CSD) at different shear rates by Brownian dynamics in non-, bi-, and uni-polar systems with partly charged superfine particles, The investigation indicates that clusters in non- polar systems are the weakest and easiest to be damaged by increasing shear stresses; charged particles play important and different roles: in bi-polar system, it intends to strengthen clusters to some extent provided that the sign-like ions homogeneously arranged; in uni-polar system charged particles cracked the clusters into smaller ones, but the small clusters are strong to stand with larger shear stress. The relationship between ACS and shear rates follows power law with exponents in a range 0.18-0.28, these values are in a good agreement with experiment range but at the lower limit compared with other systems of non-metallic cluster particles.
基金supported by the National Natural Science Foundation of China(61172071,61201194)the International Scientific and Technological Cooperation and Exchange Program in Shaanxi Province,China(2015KW-013)the Scientific Research Program Funded by Shaanxi Provincial Education Department,China(16JK1711)
文摘In order to study the relationship between the non-spherical atmospheric charged particles and satellite-ground quantum links attenuation. The relationship among the particle concentration, equivalent radius, charge density of the charged particle, the attenuation coefficient and entanglement of the satellite-ground quantum link can be established first according to the extinction cross section and spectral distribution function of the non-spherical atmospheric charged particles. The quantitative relationship between atmospheric visibility and communication fidelity of satellite-ground quantum link were analyzed then. Simulation results show that the ellipsoid, Chebyshev atmospheric charged particle influences on attenuation of the satellite-ground quantum link increase progressively. When the equivalent particle radius is 0.2 gm and the particle concentration is 50 μg/m^3, the attenuation coefficient and entanglement of the satellite-ground quantum link is 9.21 dB/km, 11.46 dB/km and 0.453, 0.421 respectively; When the atmospheric visibility reduces from 8 km to 2 kin, the communication fidelity of satellite-ground quantum link decreases from 0.52 to 0.08. It is shown that the non-spherical atmospheric charged particles and atmospheric visibility influence greatly on the performance of the satellite-ground quantum link communication system. Therefore, it is necessary to adjust the parameters of the quantum-satellite communication system according to the visibility values of the atmosphere and the shapes of the charged particles in the atmosphere to improve reliability of the satellite-ground quantum link.
基金Supported by Higher Education Commission(HEC)Government of Pakistan under Indigenous5000 PhD Scholarship Program Batch-IV
文摘We investigate the effects of jet production on the following parameters: pseudorapidity, transverse momentum and transverse mass distributions of secondary charged particles produced in pp-collisions at 1.8 Te V,using the HIJING code. These distributions are analyzed for the whole range and for six selected regions of the polar angle as a function of the different number of jets. The obtained simulation results for these parameters are interpreted and discussed in connection to the increase observed in the multiplicity of secondary charged particles as a result of its multi-jet dependence, and are also discussed in comparison with the experimental results from the CDF Collaboration.
基金the National Natural Science Foundation of China(Grant No.11775128)。
文摘The spatiotemporal evolutions of a one-dimensional collisionless decaying plasma bounded by two electrodes with an externally applied electrostatic field are studied by theoretical analyses and particle-in-cell(PIC)simulations with the ion extraction process in a laser-induced plasma as the major research background.Based on the theoretical analyses,the transport process of the charged particles including electrons and ions can be divided into three stages:electron oscillation and ion matrix sheath extraction stage,sheath expansion and ion rarefaction wave propagation stage and the plasma collapse stage,and the corresponding criterion for each stage is also presented.Consequently,a complete analytical model is established for describing the ion extraction flux at each stage during the decaying of the laser-induced plasmas under an electrostatic field,which is also validated by the PIC modeling results.Based on this analytical model,influences of the key physical parameters,including the initial electron temperature and number density,plasma width and the externally applied electric voltage,on the ratio of the extracted ions are predicted.The calculated results show that a higher applied electric potential,smaller initial plasma number density and plasma width lead to a higher ratio of the extracted ions during the first stage;while in this stage,the initial electron temperature shows little effect on it.Meanwhile,more ions will be extracted before the plasma collapse once a higher electric potential is applied.The theoretical model presented in this paper is helpful not only for a deep understanding to the charged particle transport mechanisms for a bounded decaying plasma under an applied electrostatic field,but also for an optimization of the ion extraction process in practical applications.
文摘Dispersion and surface deposition of charged particles by gas-solids jets in confined chambers are constantly encountered in many industrial applications such as in electrostatic precipitation and dry powder coating processes. Understanding and control of flow patterns and trajectories of charged particles are important to the optimal design and operation of such devices. In this study, modeling of flow fields and particle trajectories of dilute gas-solid two-phase flows with charged particles in confined chambers is performed. The dilute gas-solid two-phase flows are simulated by use of a hybrid Eulerian-Lagrangian approach with the one-way coupling between the gaseous phase and particle phase. The space charge distribution is included as a source term in equations of motion or Lagrangian equation of charged particles, which in turn depends on the particle trajectories that determine the space charge distribution. Our modeling predictions suggested that the electrostatic charge plays a significant role in particle radial dispersion. Effect of voltage has limited influence on particle trajectories however it can have a big impact on the residence time. Cone angle has a significant effect on the structure of flow field. For cone with a larger cone angle (typically over 15°), there will be a flow separation along the side wall near the flow entrance region. By comparing with the conical chamber, the cylindrical chamber has a big vortex and three smaller vortexes in the lower part of the chamber, which would complicate the particle dispersion with or without the coupling of charging.
基金supported by National Natural Science Foundation of China (Nos. 40831062, 10775134)partially supported by CAS Knowledge Innovation Program (No. kjcx2-yw-n28)National Basic Research Program of China (Nos. 2008CB717800, 2009GB105001)
文摘Time evolution of ionospheric D-region plasmas including the perturbations of electrons and charged aerosol particles is investigated under the conditions of polar mesosphere summer echoes (PMSE). It is shown that the time scale of decay of the electron density is in the order of an hour under typical PMSE conditions, in the majority of cases, the electron density is anticorrelated to the ion density, except that the radius of aerosol particles is greater than 50 nm. Also, the evolutions under varied parameters, such as the amplitude and width of perturbation, the aerosol particle radius, and the altitude of the PMSE occurrence are investigated. The obtained results are useful for interpreting the experimental observations.
基金Supported by Transformation Project of Science and Technology of Shanghai Baoshan District(CXY-2012-25)Shanghai Leading Academic Discipline Project(XTKX 2012)
文摘The revised Landau hydrodynamic model is used to discuss the pseudorapidity distributions of the produced charged particles in Au+Au and Cu+Cu collisions at energies of s √SNN=19.6 and 22.4 GeV respectively at the BNL Relativistic Heavy Ion Collider. It is found that the revised Landau hydrodynamic model alone can give a good description of the experimental measurements. This is different from the result with the same collisions but at the maximum energy of√SNN=200 GeV, where in addition to the revised Landau hydrodynamic model, the effects of leading particles have to be taken into account in order to explain the experimental observations. This can be attributed to the different degrees of transparency of participants at the different incident energies.
文摘In this paper, we describe a possible method for predicting the earthquakes, which is based on simultaneous recording of the intensity of fluxes of neutrons and charged particles by detectors, commonly used in nuclear physics. These low-energy particles originate from radioactive nuclear processes in the Earth's crust. The variations in the particle flux intensity can be the precursor of the earth- quake. A description is given of an electronic installation that records the fluxes of charged particles in the radial direction, which are a possible response to the accumulated tectonic stresses in the Earth's crust. The obtained results showed an increase in the intensity of the fluxes for 10 or more hours before the occurrence of the earthquake. The previous version of the installation was able to indicate for the possibility of an earthquake (Maksudov et al. in Instrum Exp Tech 58:130-131, 2015), but did not give information about the direction of the epicenter location. In this regard, the installation was modified by adding eight directional detectors. With the upgraded setup, we have received both the predictive signals, and signals determining the directions of the location of the forthcoming earthquake, starting 2-3 days before its origin.
基金supported by the National Natural Science Foundation of China(No.12065003)the Guangxi Key R&D Project(2023AB07029)+1 种基金the Scientific Research and Technology Development Project of Guilin(20210104-2)the Central Government Guides Local Scientific and Technological Development Funds of China(Guike ZY22096024)。
文摘Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the targets.The reaction channels,including sequential and simultaneous emission processes,are analyzed in detail.Taking the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted particles.The optical potential parameters of the proton are obtained by fitting the elastic scattering differential cross-sections.The calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing angles.Simultaneously,the mixed double differential cross-sections of^(3) He andαare in good agreement with the measurements.The agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction processes.Based on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles.
文摘The transition radiation of a charged particle crossing the interface of two media having a monatomic impurity layer is investigated. It is shown that at sliding angles of incidence of a particle on the boundary of the media, the transition radiation is mainly determined by the properties of the surface layer. The possibility of using transition radiation to study the surface of substances is discussed. In addition, due to the hard radiation present in space, this research may be important for the use of light monoatomic layers as a material for satellite antennas, “solar sails” and cover layers in a future space (interstellar) mission.
文摘In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarly charged and coagulated in the same alternating electric field simultaneously. The silica flour with 2 fun mass median diameter and the smoke from burning wood powder were used as test aerosol. The comparison experimental results have shown that when the mean electric field is 4 kV/cm the collection efficiency of the new electrostatic agglomerator was 98.2% for silica flour and 67.4% for wood powder smoke, Under the same experimental condition. the collection efficiency of the electrostatic agglomerator with three zones was 97.4% for collecting silica flour and the collection efficiency of the electrostatic precipitator was 56.3% for wood powder smoke.
基金supported by a Kawasaki Medical School Research Grant(28B051)
文摘Objective The changes in serum adipokines and cytokines related to oxidative stress were examined during 3 months ‘Off to On’ and ‘On to Off’ periods using negatively charged particle-dominant indoor air conditions(NCPDIAC).Methods Seven volunteers participated in the study,which included ‘OFF to 3 months ON’ periods(ON trials) for a total of 16 times,and ‘ON to 3 months OFF’(OFF trials) periods for a total of 13 times.Results With the exception of one case,serum amyloid A(SAA) levels decreased significantly during the ON trials.Conclusion Considering that SAA is an acute phase reactive protein such as C reactive protein(CRP),this observed decrease might indicate the prevention of cardiovascular and atherosclerotic changes,since an increase in high-sensitive CRP is associated with the subsequent detection of these events.
文摘Extending Parikh's semi-classical quantum tunnelling model, this paper has studied the Hawking radiation of the charged particle via tunnelling from the horizon of the axisymmetric Sen black hole. Different from the uncharged massless particle, the geodesics of the charged massive particle tunnelling from the horizon is not light-like. The derived result supports Parikh's opinion and provides a correct modification to Hawking strictly thermal spectrum developed by the fixed background space-time and not considering the energy conservation and the self-gravitation interaction.