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Ankle Phenomenon in the Cosmic Ray Energy Spectrum 被引量:2
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作者 Yukio Tomozawa 《Journal of Modern Physics》 2013年第3期385-389,共5页
The author has suggested that the knee phenomenon in the cosmic ray energy spectrum at 3 PeV can be explained as a split between a radiation-dominated expansion and a matter-dominated expansion of an expanding heat ba... The author has suggested that the knee phenomenon in the cosmic ray energy spectrum at 3 PeV can be explained as a split between a radiation-dominated expansion and a matter-dominated expansion of an expanding heat bath. The model proposed in 1985, in fact, predicted that high energy cosmic rays are emitted from AGN, massive black holes, in agreement with recent data from the Pierre Auger Observatory. Similarly, the ankle phenomenon at 3 EeV is shown to be explained by a split between inflational expansion and ordinary material expansion of the expanding heat bath, not unlike that in the expansion of the universe. All the spectral indicies in the respective regions of the energy spectra agree with the theoretical calculation from the respective expansion rates. It is shown that the ankle energy is approximately equal to the threshold energy of cosmic ray production of an electron positron pair on the cmb photon. 展开更多
关键词 COSMIC rayS COSMOLOGY Knee energy INFLATION
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Fast forward modeling of muon transmission tomography based on model voxelization ray energy loss projection
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作者 Zhang Rong-Qing Xi Zhen-Zhu +2 位作者 Liu Wei Wang He Yang Zi-Yan 《Applied Geophysics》 SCIE CSCD 2022年第3期395-408,471,共15页
To solve the problems associated with low resolution and high computational effort infinite time,this paper proposes a fast forward modeling method for muon energy loss transmission tomography based on a model voxeliza... To solve the problems associated with low resolution and high computational effort infinite time,this paper proposes a fast forward modeling method for muon energy loss transmission tomography based on a model voxelization energy loss projection algorithm.First,the energy loss equation for muon transmission tomography is derived from the Bethe–Bloch formula,and the imaging region is then dissected into several units using the model voxelization method.Thereafter,the three-dimensional(3-D)imaging model is discretized into parallel and equally spaced two-dimensional(2-D)slices using the model layering method to realize a dimensional reduction of the 3-D volume data and accelerate the forward calculation speed.Subsequently,the muon energy loss transmission tomography equation is discretized using the ray energy loss projection method to establish a set of energy loss equations for the muon penetration voxel model.Finally,the muon energy loss values at the outgoing point are obtained by solving the projection coefficient matrix of the ray length-weighted model,achieving a significant reduction in the number of muons and improving the computational efficiency.A comparison of our results with the simulation results based on the Monte Carlo method verifies the accuracy and effectiveness of the algorithm proposed in this paper.The metallic mineral identification tests show that the proposed algorithm can quickly identify high-density metallic minerals.The muon energy loss response can accurately identify the boundary of the anomalies and their spatial distribution characteristics. 展开更多
关键词 Muon transmission tomography model voxelization ray energy loss projection fast forward modeling Monte Carlo simulation
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Study of Cosmic-Ray Energy Spectrum during Solar Weather Disturbance
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作者 Turlan Sadykov Olga Novolodskaya Emar Tautaev Natalya Zastrozhnova Mark Zhunusbekov 《Journal of Physical Science and Application》 2014年第7期450-453,共4页
The purpose of this experiment is to investigate the dynamics of the intensity of cosmic ray flows and to obtain the energy spectrum of solar cosmic rays according to the data of measurements of neutron monitors at th... The purpose of this experiment is to investigate the dynamics of the intensity of cosmic ray flows and to obtain the energy spectrum of solar cosmic rays according to the data of measurements of neutron monitors at the height of 3,340, 1,700, 800 meters above the sea level. Also the estimation of energy spectrum of cosmic rays flows during the disturbances of solar activity (GLE) was made. 展开更多
关键词 Cosmic rays energy spectrum neutron monitors
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Ultra High Energy Cosmic Rays: Spectral Signatures and Observations
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作者 Svetlana Grigorieva 《Journal of Physical Science and Application》 2014年第6期393-397,共5页
The observations of Ultra High Energy Cosmic Rays (UHECR) are renewed, focusing on the energy spectra as measured by HiRes, Telescope Array (TA) and Auger detectors (PAO). It is found that highest energy Auger s... The observations of Ultra High Energy Cosmic Rays (UHECR) are renewed, focusing on the energy spectra as measured by HiRes, Telescope Array (TA) and Auger detectors (PAO). It is found that highest energy Auger steepening does not agree with GZK cutoff, which is most probably explained by the nuclei mass composition detected by Auger. At present the difference in mass composition in Auger and HiRes/TA data remains the main unsolved problem of UHECR origin. 展开更多
关键词 Ultrahigh energy cosmic ray origin CMB radiation GZK cutoff.
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The Effect of Spatial Structure Character of Heat Source on the Ray Path and the Evolution of Wave Energy of Meridional Wave Train
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作者 徐祥德 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第1期87-98,共12页
This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional l... This paper studies correlations between the spatial structure character of thermal forcing and deformation and the amplitude of rays of meridional wave train. It is shown that if thermal forcing appears a meridional linear variation the rays of quasi-stationary planetary wave may propagate along oblique lines and if the meridional variability of heat source has second order term the rays show distinct deformation as a great circular route. Additionally, the inhomogeneous distribution may cause lower frequency oscillations in mid- and low-latitudes. The combination of zonal and meridional wave numbers and distributive character of heat source may form an inverse mechanism of variational trend of generized wave energy, reflecting in some degree the physical process of transition between meridional and zonal flow patterns. 展开更多
关键词 The Effect of Spatial Structure Character of Heat Source on the ray Path and the Evolution of Wave energy of Meridional Wave Train PATH Wave
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Absence of the Impact of the Flux of Cosmic Rays and the Cloud Cover on the Energy Balance of the Earth
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作者 H.I.Abdussamatov 《Journal of Atmospheric Science Research》 2020年第3期1-7,共7页
The energy of solar radiation absorbed by the Earth,as well as the thermal radiation of the Earth’s surface,which is released to the space through the atmospheric transparency window,depends on variations of the area... The energy of solar radiation absorbed by the Earth,as well as the thermal radiation of the Earth’s surface,which is released to the space through the atmospheric transparency window,depends on variations of the area of the cloud cover.Svensmark et al.suggest that the increase in the area of the cloud cover in the lower atmosphere,presumably caused by an increase in the flux of galactic cosmic rays during the quasi-bicentennial minimum of solar activity,results only in an increase in the fraction of the solar radiation reflected back to the space and weakens the flux of the solar radiation that reached the Earth surface.It is suggested,without any corresponding calculations of the variations of the average annual energy balance of the EarthЕ,that the consequences will include only a deficit of the solar energy absorbed by the Earth and a cooling of the climate up to the onset of the Little Ice Age.These suggestions ignore simultaneous impact of the opposite aspects of the increase in the area of the cloud cover on the climate warming.The latter will result from a decrease in the power of thermal radiation of the Earth’s surface released to the space,and also in the power of the solar radiation reflected from the Earth’s surface,due to the increase in their absorption and reflection back to the surface.A substantial strengthening in the greenhouse effect and the narrowing of the atmospheric transparency window will also occur.Here,we estimate the impact of all aspects of possible long-term 2%growth of the cloud cover area in the lower atmosphere byЕ.We found that an increase in the cloud cover area in the lower atmosphere will result simultaneously both in the decrease and in the increase in the temperature,which will virtually compensate each other,while the energy balance of the Earth E before and after the increase in the cloud cover area by 2%will stay essentially the same:E1-E0≈0. 展开更多
关键词 CLIMATE Cosmic rays Cloud Cover energy Balance Little Ice Age Solar Irradiance Greenhouse Effect Atmospheric Transparency Window
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The temperature-dependent fracture strength model for ultra-high temperature ceramics 被引量:15
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作者 Weiguo Li Fan Yang Daining Fang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第2期235-239,共5页
Breaking down the entire structure of a material implies severing all the bonds between its atoms either by applying work or by heat transfer. Because bond-breaking is indifferent to either means, there is a kind of e... Breaking down the entire structure of a material implies severing all the bonds between its atoms either by applying work or by heat transfer. Because bond-breaking is indifferent to either means, there is a kind of equivalence between heat energy and strain energy. Based on this equivalence, we assume the existence of a constant maximum storage of energy that includes both the strain energy and the corresponding equivalent heat energy. A temperaturedependent fracture strength model is then developed for ultrahigh temperature ceramics (UHTCs). Model predictions for UHTCs, HfB2, TiC and ZrB2, are presented and compared with the experimental results. These predictions are found to be largely consistent with experimental results. 展开更多
关键词 ultra-high temperature ceramics · Equivalent energy · Critical failure energy · Strength model
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Variations in Wave Energy and Amplitudes along the Energy Dispersion Paths of Nonstationary Barotropic Rossby Waves 被引量:2
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作者 Yaokun LI Jiping CHAO Yanyan KANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2021年第1期49-64,共16页
The variations in the wave energy and the amplitude along the energy dispersion paths of the barotropic Rossby waves in zonally symmetric basic flow are studied by solving the wave energy equation,which expresses that... The variations in the wave energy and the amplitude along the energy dispersion paths of the barotropic Rossby waves in zonally symmetric basic flow are studied by solving the wave energy equation,which expresses that the wave energy variability is determined by the divergence of the group velocity and the energy budget from the basic flow.The results suggest that both the wave energy and the amplitude of a leading wave increase significantly in the propagating region that is located south of the jet axis and enclosed by a southern critical line and a northern turning latitude.The leading wave gains the barotropic energy from the basic flow by eddy activities.The amplitude continuously climbs up a peak at the turning latitude due to increasing wave energy and enlarging horizontal scale(shrinking total wavenumber).Both the wave energy and the amplitude eventually decrease when the trailing wave continuously approaches southward to the critical line.The trailing wave decays and its energy is continuously absorbed by the basic flow.Furthermore,both the wave energy and the amplitude oscillate with a limited range in the propagating region that is located near the jet axis and enclosed by two turning latitudes.Both the leading and trailing waves neither develop nor decay significantly.The jet works as a waveguide to allow the waves to propagate a long distance. 展开更多
关键词 barotropic Rossby waves energy dispersion wave ray theory wave energy AMPLITUDE
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Fractional-Order Control of a Wind Turbine Using Manta Ray Foraging Optimization 被引量:2
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作者 Hegazy Rezk Mohammed Mazen Alhato +1 位作者 Mohemmed Alhaider Soufiene Bouallègue 《Computers, Materials & Continua》 SCIE EI 2021年第7期185-199,共15页
In this research paper,an improved strategy to enhance the performance of the DC-link voltage loop regulation in a Doubly Fed Induction Generator(DFIG)based wind energy system has been proposed.The proposed strategy u... In this research paper,an improved strategy to enhance the performance of the DC-link voltage loop regulation in a Doubly Fed Induction Generator(DFIG)based wind energy system has been proposed.The proposed strategy used the robust Fractional-Order(FO)Proportional-Integral(PI)control technique.The FOPI control contains a non-integer order which is preferred over the integer-order control owing to its benefits.It offers extra flexibility in design and demonstrates superior outcomes such as high robustness and effectiveness.The optimal gains of the FOPI controller have been determined using a recent Manta Ray Foraging Optimization(MRFO)algorithm.During the optimization process,the FOPI controller’s parameters are assigned to be the decision variables whereas the objective function is the error racking that to be minimized.To prove the superiority of the MRFO algorithm,an empirical comparison study with the homologous particle swarm optimization and genetic algorithm is achieved.The obtained results proved the superiority of the introduced strategy in tracking and control performances against various conditions such as voltage dips and wind speed variation. 展开更多
关键词 Renewable energy MODELING wind turbine doubly fed induction generator fractional order control manta ray foraging optimization
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Understanding the Function of Rays and Wood Density on Transverse Fracture Behaviour of Green Wood in Three Species 被引量:2
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作者 Seray Ozden Anthony Roland Ennos 《Journal of Agricultural Science and Technology(B)》 2014年第9期731-743,共13页
In recent years, there has been an increasing interest in wood properties, because wood is a commonly used and advanced building material. In this paper, the effect of anatomical characters on the transverse fracture ... In recent years, there has been an increasing interest in wood properties, because wood is a commonly used and advanced building material. In this paper, the effect of anatomical characters on the transverse fracture properties of green wood was investigated. The specific fracture energy (Gf J/m2) of ash (Fraxinus excelsior), cherry (Prunus avium) and birch (Betula pendula) was evaluated using double edge notched tensile tests. The tests were performed on both earlywood (EW) and latewood (LW) zones in both the radial-tangential (RT) and the tangential-radial (TR) crack propagation systems. Wood anatomy and the failure patterns of each species were also investigated using environmental scanning electron microscopy (ESEM) and light microscopy (LMC). The results showed that the Gfof RT fracture systems was around 1.5 times greater than in the TR one, whereas there were no significant differences between EW and LW zones. ESEM micrographs showed that the RT fracture system had a rougher fracture surface, while the TR had a nearly smooth and fiat fracture surface. In particular, the wood ofF. excelsior was the toughest, because of its greater percentage of rays and homogenous distribution of ray cells, while P. avium and B. pendula showed a lower Gf due to their smaller percentage of rays with a distinctive arrangement of ray cells. 展开更多
关键词 Green wood fracture energy rayS transverse failure.
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About the Energy Interval beyond the Ankle Where the Cosmic Radiation Consists Only of Ultraheavy Nuclei from Zinc to the Actinides 被引量:1
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作者 Antonio Codino 《Journal of Applied Mathematics and Physics》 2017年第1期225-237,共13页
According to recent measurements the tendency of the chemical composition above the ankle is characterized by increasing fractions of intermediate and heavy nuclei and a dominance of light nuclei around the ankle. Cal... According to recent measurements the tendency of the chemical composition above the ankle is characterized by increasing fractions of intermediate and heavy nuclei and a dominance of light nuclei around the ankle. Calculation of the chemical composition in the range 3.5 × 1018 - 5 × 1019 eV according to new principles explains both the rising tendency of the heavy component. The calculation is prolonged to the adjacent interval 5 × 1019- 2.4 × 1021 eV using the same theoretical background and some features of the observed cosmic-ray spectrum. It results that above the energy of 6.7 × 1020 eV, where the flux is estimated to be 1.8 × 10?30 particles/m2 s sr GeV, the cosmic radiation consists only of nuclei heavier than Zinc. Measurements of the spectrum of present and past experiments are compared with the calculations. 展开更多
关键词 Ultrahigh energy COSMIC ray Chemical Composition GZK Effect
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Research on Irradiation Electric Field for Charged Particles Beam with High Energy 被引量:1
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作者 Jianping Shi Yijia Tang +2 位作者 Lingli Zhan Hongjian Liu Xunan Chen 《Engineering(科研)》 2011年第1期17-21,共5页
Irradiation protection of the nonlinear optical devices used in the spacecraft and next generation active laser system must be solved. The first problem was to find the irradiation damage mechanism of the nonlinear ma... Irradiation protection of the nonlinear optical devices used in the spacecraft and next generation active laser system must be solved. The first problem was to find the irradiation damage mechanism of the nonlinear materials. In this paper the irradiation electronic field originating from high speed charged particle beams was discussed. The calculating model of the electronic field, based on the relativistic mechanics and electro-magnetic theory, was founded. The common characters of the irradiation electronic field were predicted and the fields of α ray and β ray were calculated by means of our model. The simulating results showed that the intensity of the electric field increased with the energy or the intensity of the beam. The results also showed that the field change trend of α ray and β ray was similar, but the field value was quite different. When the beam intensity I = 100 μA and the beam energy εm = 500 Mev, the electronic field values were about 3.5 × 107 v/m for α ray and 2.4 × 1011 v/m for β ray. 展开更多
关键词 CHARGED-PARTICLES BEAM with High energy Irradiating Damage IRRADIATION Electronic Field α ray β ray
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A Model of Dark Matter and Dark Energy Based on Relativizing Newton’s Physics 被引量:2
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作者 Ramzi Suleiman 《World Journal of Condensed Matter Physics》 2018年第3期130-155,共26页
The nature and properties of dark matter and dark energy in the universe are among the outstanding open issues of modern cosmology. Despite extensive theoretical and empirical efforts, the question “what is dark matt... The nature and properties of dark matter and dark energy in the universe are among the outstanding open issues of modern cosmology. Despite extensive theoretical and empirical efforts, the question “what is dark matter made of?” has not been answered satisfactorily. Candidates proposed to identify particle dark matter span over ninety orders of magnitude in mass, from ultra-light bosons, to massive black holes. Dark energy is a greater enigma. It is believed to be some kind of negative vacuum energy, responsible for driving galaxies apart in accelerated motion. In this article we take a relativistic approach in theorizing about dark matter and dark energy. Our approach is based on our recently proposed Information Relativity theory. Rather than theorizing about the identities of particle dark matter candidates, we investigate the relativistic effects on large scale celestial structures at their recession from an observer on Earth. We analyze a simplified model of the universe, in which large scale celestial bodies, like galaxies and galaxy clusters, are non-charged compact bodies that recede rectilinearly along the line-of-sight of an observer on Earth. We neglect contributions to dark matter caused by the rotation of celestial structures (e.g., the rotation of galaxies) and of their constituents (e.g., rotations of stars inside galaxies). We define the mass of dark matter as the complimentary portion of the derived relativistic mass, such that at any given recession velocity the sum of the two is equal to the Newtonian mass. The emerging picture from our analysis could be summarized as follows: 1) At any given redshift, the dark matter of a receding body exists in duality to its observable matter. 2) The dynamical interaction between the dark and the observed matter is determined by the body’s recession velocity (or redshift). 3) The observable matter mass density decreases with its recession velocity, with matter transforming to dark matter. 4) For redshifts z 0.5 the universe is dominated by dark matter. 5) Consistent with observational data, at redshift z = 0.5, the densities of matter and dark matter in the universe are predicted to be equal. 6) At redshift equaling the Golden Ratio (z ≈ 1.618), baryonic matter undergoes a quantum phase transition. The universe at higher redshifts is comprised of a dominant dark matter alongside with quantum matter. 7) Contrary to the current conjecture that dark energy is a negative vacuum energy that might interact with dark matter, comparisons of our theoretical results with observational results of ΛCDM cosmologies, and with observations of the relative densities of matter and dark energy at redshift z ≈ 0.55, allow us to conclude that dark energy is the energy carried by dark matter. 8) Application of the model to the case of rotating bodies, which will be discussed in detail in a subsequent paper, raises the intriguing possibility that the gravitational force between two bodies of mass is mediated by the entanglement of their dark matter components. 展开更多
关键词 DARK Matter DARK energy GZK COSMIC rayS CUTOFF ΛCDM Cosmology COINCIDENCE Problem Quantum Phase Transition Gravity Golden Ratio
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Development of Magnetic Compound Fluid Rubber Sensor for Practical Usage on &gamma;-Irradiation and Energy Harvesting for Broad-Band Electromagnetic Waves 被引量:1
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作者 Kunio Shimada Ryo Ikeda +1 位作者 Hiroshige Kikura Hideharu Takahashi 《World Journal of Mechanics》 2019年第9期205-231,共27页
We have performed sequential studies on new types of soft rubber for their application as artificial skin in robots and haptic sensors. Based on a proposed electrolytic polymerization method and novel adhesion techniq... We have performed sequential studies on new types of soft rubber for their application as artificial skin in robots and haptic sensors. Based on a proposed electrolytic polymerization method and novel adhesion technique for rubber and a metal that utilizes a metal complex hydrate, we have developed an MCF rubber sensor. This sensor uses a magnetic compound fluid (MCF), natural rubber (NR-latex) or chloroprene rubber latex (CR-latex), and requires the application of a magnetic field. The potential application of the developed sensor in various engineering scenarios and our daily lives is significant. In this regard, we investigated the effects of &gamma;-irradiation, infrared radiation, microwaves, and a thermal source on the MCF rubber sensor. We established that the MCF rubber is effective enough to be used for power generation of broadband electro-magnetic waves from &gamma;-rays to microwaves, including the range of the solar spectrum, which is the typical characteristic obtained in the present investigation. The remarkable attribute is that the MCF rubber sensor dose is not degraded by &gamma;-irradiation. We also demonstrated the effectiveness of the MCF rubber sensor in energy harvesting. 展开更多
关键词 Γ-IRRADIATION Photovoltaics energy Harvesting Mechanical Property Thermal Source Infrared rays Electromagnetic Waves Induced Voltage Natural RUBBER CHLOROPRENE RUBBER Adhesion Electrolytic Polymerization MAGNETIC Cluster MAGNETIC Field MAGNETIC COMPOUND FLUID (MCF) Sensing Robot
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Alleviating freshwater shortages with combined desert-based large-scale renewable energy and coastal desalination plants supported by Global Energy Interconnection
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作者 Hengxu Zhang Yuzheng Xie 《Global Energy Interconnection》 2019年第3期205-213,共9页
Under the background of sustainable energy transition and environmental protection,Global Energy Interconnection(GEI),which features an innovative combination of clean energy(e.g.,solar power) and ultra-high voltage(U... Under the background of sustainable energy transition and environmental protection,Global Energy Interconnection(GEI),which features an innovative combination of clean energy(e.g.,solar power) and ultra-high voltage(UHV) transmission technologies,provides a means to realize global climate governance.China is a large country with unevenly distributed water resources,energy production,and energy consumption,and the large areas of desert in northern and western China have the potential for installing large-scale solar power plants.This study analyzed the potential of using large-scale solar power from deserts to coastal seawater desalination plants,which could alleviate the freshwater crisis and control desertification in China.First,the measurement data from NASA were used to estimate the potential exploitable amount of solar energy in desert areas.A macro idea was proposed for the transmission of electrical power from inland integrated energy bases to coastal seawater desalination and pumping of freshwater to western China to combat desertification and alleviate the freshwater crisis.Based on this,the electricity demands for desalination and water redistribution were estimated.As a huge interruptible load,desalination and pumping systems could be used to suppress power fluctuations of the integrated energy bases.Finally,the fundamental support roles of UHV grids in large-scale renewable energy allocation and utilization were discussed.This analysis offers a theoretical framework to help realize efficient renewable energy generation and consumption and alleviate freshwater shortage. 展开更多
关键词 DESERT Desalination energy crisis FRESHWATER GLOBAL energy INTERCONNECTION (GEI) Solar energy ultra-high voltage (UHV).
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The Energy Spectrum of Ultraheavy Nuclei above 10<sup>20</sup>eV
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作者 Antonio Codino 《Journal of Applied Mathematics and Physics》 2017年第8期1540-1550,共11页
A major feature of the energy spectrum of the cosmic radiation above 1019 eV is the increasing fraction of heavy nuclei with respect to light nuclei. This fact, along with other simple assumptions, is adopted to calcu... A major feature of the energy spectrum of the cosmic radiation above 1019 eV is the increasing fraction of heavy nuclei with respect to light nuclei. This fact, along with other simple assumptions, is adopted to calculate the energy spectrum of the cosmic radiation up to 2.4 × 1021 eV. The predicted spectrum maintains the index of 2.67 observed at lower energies which is the basic, known, empirical well-assessed feature of the physical mechanism accelerating cosmic rays in the Galaxy. Indeed above 1019 eV the injection of nuclei is inhibited by some filter and this inhibition causes a staircase profile of the energy spectrum. It is argued that particle injection failure versus energy commences with protons, followed by Helium and then by other heavier nuclei up to Uranium. Around 7.5 × 1020 the cosmic radiation consists solely of nuclei heavier than Copper and the estimated intensity is 1.8 × 10-30 particles/GeV s sr m2. 展开更多
关键词 ANKLE energy ultra-high energy GZK Effect Ultraheavy NUCLEI
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On-Site Calibration Method of Dosimeter Based on X-Ray Source
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作者 Wenhui Lv Huiping Guo +4 位作者 Ning Lv Chenyang Tian Kuo Zhao Xiaotian Wang Yijie Hou 《World Journal of Nuclear Science and Technology》 2017年第2期93-102,共10页
The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nu... The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nuclear facilities there are so many environmental dosimeters installed dispers-edly, because of its huge quantity, widely distributed, and in real-time monitoring state;it will cost lots of manpower and finance if it were tak-en to calibrate on standard laboratory;what’s more it will make the en-vironment out of control. To solve the problem of the measurement ac-curacy of the stationary gamma radiation dosimeter, an on-site calibra-tion method is proposed. The radioactive source is X-ray spectrum, and the dose reference instrument which has been calibrated by the national standard laboratory is a high pressure ionization. On-site calibration is divided into two parts;firstly the energy response experiment of dosim-eter for high and low energy is done in the laboratory, and the energy response curve is obtained combining with Monte Carlo simulation;sec-ondly experiment is carried out in the field of the measuring dosimeter, and the substitution method to calibrate the dosimeter is used;finally the calibration coefficient is gotten through energy curve correction. In order to verify the accuracy of on-site calibration method, the calibrated dosimeter is test in the standard laboratory and the error is 3.4%. The re-sult shows that the on-site calibration method using X-ray is feasible, and it can improves the accuracy of the measurement results of the stationary &gamma;-ray instrument;what’s more important is that it has great reference value for the radiation safety management and radiation environment evaluation. 展开更多
关键词 X ray SOURCE ON-SITE Calibration energy Response GAMMA RADIATION DOSIMETER
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Cosmic Applications of Relative Energy between Quarks in Nucleons
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作者 F. C. Hoh 《Journal of Modern Physics》 2019年第14期1645-1658,共14页
By taking into account the relative energy between the diquark and the quark in nucleons, the gravitational singularity in a black hole created from a collapsing neutron star can be removed;compatibility with quantum ... By taking into account the relative energy between the diquark and the quark in nucleons, the gravitational singularity in a black hole created from a collapsing neutron star can be removed;compatibility with quantum mechanics is restored. This black hole becomes a “black” neutron star. The negative relative energy identified as dark matter in the previous paper can account for the galaxy rotation curve. The positive relative energy identified as dark energy in the previous paper can explain the accelerating expansion of the universe. A possible scenario for cosmic ray generation is given. 展开更多
关键词 Gravitational Singularity Relative energy BETWEEN QUARKS Scalar Strong Interaction HADRON Theory “Weightless” NEUTRON Black NEUTRON Star Galaxy Rotation Curve Accelerating Expansion of Universe COSMIC ray
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A Study on Two-dimensional Spectrum Analysis System of Energy and Time
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作者 ZHANG Liuqiang LI Yinglin +1 位作者 ZHANG Jian YUAN Yuan 《Instrumentation》 2022年第3期1-9,共9页
Proposed is a two-dimensional(2D)spectrum analysis system for acquiring the statistical information of radioactive particles on two dimensions,i.e.energy and time.Based on pulse width modulation readout circuit,such a... Proposed is a two-dimensional(2D)spectrum analysis system for acquiring the statistical information of radioactive particles on two dimensions,i.e.energy and time.Based on pulse width modulation readout circuit,such a system with 4-channels is designed,which converts the radiation signal into a rectangular pulse signal with pulse width modulated.The pulse width,occurrence time,and pulse count of the rectangular pulses are measured simultaneously with digital counters,so that the 2D spectra on energy and time of the radioactive particles can be obtained efficiently based on bi-parameter statistical analysis.A prototype of this 2D system is tested with gamma rays from 241Am isotopes,from which both the correlated 2D spectra and the independent spectra on energy and time are obtained.The energy spectra of four channels shows all characteristic peaks of 241Am gamma rays,among which the full-energy peak at 59.5keV exhibits energy resolution of about 5-6%,suggesting a good energy resolution and channel uniformity of the system.The regression of the time spectra of the characteristic peaks can give the time constants of each characteristic peak,revealing the time characteristics of the nuclear reactions in the radiative source. 展开更多
关键词 energy Spectrum Time Spectrum Two-dimensional Spectrum Pulse Width Modulation Gamma ray
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Ballistic Penetration Damage of Hybrid Thermoplastic Composites Reinforced with Kevlar and UHMWPE Fabrics
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作者 LI Zhiyong XUE Yousong +1 位作者 SUN Baozhong GU Bohong 《Journal of Donghua University(English Edition)》 CAS 2024年第4期398-404,共7页
Polymer matrix types of fiber hybrid composites are key factors to improve ballistic impact damage tolerances.Here we report ballistic penetration damages of Kevlar/ultra-high molecular weight polyethylene(UHMWPE)hybr... Polymer matrix types of fiber hybrid composites are key factors to improve ballistic impact damage tolerances.Here we report ballistic penetration damages of Kevlar/ultra-high molecular weight polyethylene(UHMWPE)hybrid composites with thermoplastic polyurethane(PU)matrix.The hybrid composites were penetrated by fragment-simulating projectiles(FSPs)using an air gun impact system.The effects of stacking sequences on the ballistic performance of hybrid composites were analyzed.Two types of specific energy absorption(the energy absorption per unit area density and the energy absorption per unit thickness)were investigated.It was found that the main damage modes of PU hybrid composites were fiber breakage,matrix damage,fiber pullout and interlayer delamination.The instantaneous deformation could not be used as a reference index for evaluating the ballistic performance of the target plate.The energy absorption process of the PU hybrid composites showed a nonlinear pattern.The hybrid structure affected the specific energy absorption of the materials. 展开更多
关键词 polyurethane(PU) KEVLAR ultra-high molecular weight polyethylene(UHMWPE) hybrid composite ballistic impact specific energy absorption
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