A series of magnetic properties of Tm_2Fe_(14)B are explained quantitatively by the calculations based on the single ion model. The magnetic properties include the temperature dependence of the spontaneous magnetizati...A series of magnetic properties of Tm_2Fe_(14)B are explained quantitatively by the calculations based on the single ion model. The magnetic properties include the temperature dependence of the spontaneous magnetization, the spin reorientation temperature and the magnetization curves along the principal crystal axes at 4.2, 100, 150 and 200 K. The values of the exchange field and the crystalline electric field parameters used in the calculations are μ_BH_(ex)(T=0 K)=135, B_2~0=1.77, B_2~2=±2.97, B_4~0=-3.06×10^(-3), B_4^(-2)=0, B_4~4=-6.82×10^(-3), B_6~0=1.05× 10^(-5), B_6^(-2)=±7.40×10^(-5), B_6~4=1.96×10^(-4), and B_6^(-6)=0 all in K unit. The magnetization processes of the Fe-and Tm-sublattices at different temperatures are analysed. The processes are characterized by the non-collinearity between the magnetic moments of the Fe-and Tm-sublattices.展开更多
The potential of bulk-like WTe2 particles for the realization of a passive Q-switch operating at the 1 μm wavelength was investigated. The WTe2 particles were prepared using a simple mechanical exfoliation method tog...The potential of bulk-like WTe2 particles for the realization of a passive Q-switch operating at the 1 μm wavelength was investigated. The WTe2 particles were prepared using a simple mechanical exfoliation method together with Scotch tape. By attaching bulk-like WTe2 particles, which remained on the top of the sticky surface of a small segment of the Scotch tape, to the flat side of a side-polished fiber, a saturable absorber（SA） was readily implemented. A strong saturable absorption was then readily obtained through an evanescent field interaction with the WTe2 particles. The modulation depth of the prepared SA was measured as ~2.18% at 1.03 μm. By incorporating the proposed SA into an all-fiberized ytterbium-doped fiber ring cavity, stable Qswitched pulses were readily achieved.展开更多
Three-dimensional holographic vector of atomic interaction field（3D-HoVAIF） is used to describe the chemical structures of polychlorinated naphthalenes（PCNs）.After variable screening by stepwise multiple regressio...Three-dimensional holographic vector of atomic interaction field（3D-HoVAIF） is used to describe the chemical structures of polychlorinated naphthalenes（PCNs）.After variable screening by stepwise multiple regression（SMR） technique,the liner relationships between gas-chromatographic relative retention time（RRT）,298 K supercooled liquid pressures（logPL）,n-octanol/air partition coefficient（logKOA）,n-octanol/water partition coefficient（logKOW）,aqueous solubilities（logSW）,relative in vitro potency values（-logEROD） of PCNs and 3D-HoVAIF descriptors have been established by partial least-square（PLS） regression.The result shows that the 3D-HoVAIF descriptors can be well used to express the quantitative structure-property（activity） relationships of PCNs.Predictive capability of the models has also been demonstrated by leave-one-out cross-validation.Moreover,the predicted values have been presented for those PCNs which are lack of experimentally physico-chemical properties and biological activity by the optimum models.展开更多
Study on the quantitative structure-activity relationship （QSAR） of 26 compounds, N-[5-（2-furanyl）-2-methyl-4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide and 3-substituted- 5-（2-furanyl）-2-methyl-3H-thieno[2...Study on the quantitative structure-activity relationship （QSAR） of 26 compounds, N-[5-（2-furanyl）-2-methyl-4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide and 3-substituted- 5-（2-furanyl）-2-methyl-3H-thieno[2,3-d]pyrimidin-4-ones, with three-dimensional holographic vector of atomic interaction field （3D-HoVAIF） was carried out. SMR-PLS QSAR models have been created and good correlation coefficients and cross-validated correlation coefficients were obtained. The result shows that the models have good prediction capability and favorable stability and the 3D-HoVAIF is applicable to the molecular structural characterization and biological activity prediction.展开更多
The resonance interaction of two-state atoms with single mode field is described theoretically by using the semi-classical theory and Jaynes-Cummings model. The nonlinear characteristics of this system are calculated ...The resonance interaction of two-state atoms with single mode field is described theoretically by using the semi-classical theory and Jaynes-Cummings model. The nonlinear characteristics of this system are calculated by using FFT and Runge-Kutta methods. The chaotic strange attractors in this system are obtained from the numerical results.展开更多
We investigate the effects of pure Dzyaloshinskii Moriya （DM） interaction with magnetic field on entanglement in intrinsic decoherence, assuming that the system is initially in four Bell states ｜φ±〉 = （｜00...We investigate the effects of pure Dzyaloshinskii Moriya （DM） interaction with magnetic field on entanglement in intrinsic decoherence, assuming that the system is initially in four Bell states ｜φ±〉 = （｜00） ± ｜11〉）/√2 and ｜ψ±〉 = （｜01） ±｜10〉）/√2, respectively. It is found that if the system is initially in the state p1（0） = ｜φ＋〉〈φ＋1, the entanglement can obtain its maximum when the DM interaction vector D is in the plane of XOZ and magnetic field B = By with the infinite time t, moreover the entanglement is independent of By and t when By is perpendicular to D. In addition, we obtain similar results when the system is initially in the states p2（0） = ｜φ-〉〈φ-｜ or p3 （0） = ｜ψ＋〉〈ψ＋1. However, we find that if the system is initially in the state P4 （0） = ｜ψ-〉〈ψ-l, the entanglement can obtain its maximum for infinite t, when the DM vector is in the plane ofYOZ, XOZ, or XOY, with the magnetic field parallel to X, Y, or Z axis, respectively. Moreover, when the axial B is perpendicular to D for the initial state p4（O）, the negativity oscillates with time t and reaches a stable value, the larger the value of B is, the greater the stable value is, and the shorter the oscillation time of the negativity is. Thus we can adjust the direction and value of the external magnetic field to obtain the maximal entanglement, and avoid the adverse effects of external environment in some initial state. This is feasible within the cun＇ent experimental technology.展开更多
We investigate spin squeezing effects of trapped ions in an off-resonance optical potential system using the arbitrary range spin spin interaction and transverse field model. The collective spin noises at any time are...We investigate spin squeezing effects of trapped ions in an off-resonance optical potential system using the arbitrary range spin spin interaction and transverse field model. The collective spin noises at any time are analyzed exactly. The general expression of spin squeezing factor is presented for arbitrary-range spin interaction. For the nearest-neighbor and next-nearest neighbor spin interaction model, the analytic solutions are reduced from the general expressions. It is shown that the maximum spin squeezing is enhanced for the general arbitrary-range spin interaction compared with the nearest-neighbor interaction model as the long-range interaction with arbitrary sites enforces stronger correlation.展开更多
In this paper, the nonlinear interaction of ultra-high power laser beam with fusion plasma at relativistic regime in the presence of obliquely external magnetic field has been studied. Imposing an external magnetic fi...In this paper, the nonlinear interaction of ultra-high power laser beam with fusion plasma at relativistic regime in the presence of obliquely external magnetic field has been studied. Imposing an external magnetic field on plasma can modify the density profile of the plasma so that the thermal conductivity of electrons reduces which is considered to be the decrease of the threshold energy for ignition. To achieve the fusion of Hydrogen–Boron(HB) fuel,the block acceleration model of plasma is employed. Energy production by HB isotopes can be of interest, since its reaction does not generate radioactive tritium. By using the inhibit factor in the block model acceleration of plasma and Maxwell's as well as the momentum transfer equations, the electron density distribution and dielectric permittivity of the plasma medium are obtained. Numerical results indicate that with increasing the intensity of the external magnetic field, the oscillation of the laser magnetic field decreases, while the dielectric permittivity increases. Moreover, the amplitude of the electron density becomes highly peaked and the plasma electrons are strongly bunched with increasing the intensity of external magnetic field. Therefore, the magnetized plasma can act as a positive focusing lens to enhance the fusion process. Besides, we find that with increasing θ-angle(from oblique external magnetic field) between 0 and 90°, the dielectric permittivity increases, while for θ between 90° and 180°, the dielectric permittivity decreases with increasing θ.展开更多
Studying the two famous old problems that why the moon can move around the Sun and why the orbit of the Moon around the Earth cannot be broken off by the Sun under the condition calculating with <em>F</em>...Studying the two famous old problems that why the moon can move around the Sun and why the orbit of the Moon around the Earth cannot be broken off by the Sun under the condition calculating with <em>F</em>=<em>GMm</em>/<em>R</em><sup>2</sup>, the attractive force of the Sun on the Moon is almost 2.2 times that of the Earth, we found that the planet and moon are unified as one single gravitational unit which results in that the Sun cannot have the force of <em style="white-space:normal;">F</em><span style="white-space:normal;">=</span><em style="white-space:normal;">GMm</em><span style="white-space:normal;">/</span><em style="white-space:normal;">R</em><sup style="white-space:normal;">2</sup> on the moon. The moon is moved by the gravitational unit orbiting around the Sun. It could indicate that the gravitational field of the moon is limited inside the unit and the gravitational fields of both the planet and moon are unified as one single field interacting with the Sun. The findings are further clarified by reestablishing Newton’s repulsive gravity.展开更多
QED(quantum electrodynamics)is the QFT(quantum field theory)describing the interaction between light and matter.While conventional QED is based on TEM(transverse electromagnetic)waves,there has been increasing interes...QED(quantum electrodynamics)is the QFT(quantum field theory)describing the interaction between light and matter.While conventional QED is based on TEM(transverse electromagnetic)waves,there has been increasing interest in the theoretical and experimental exploration of LSW(longitudinal scalar waves)solutions that are often omitted in CED(classical electrodynamics)but may have physical significance in nontrivial vacuum conditions.This paper delves into the theoretical foundation of LSW,their role in QED,and the associated mathematical equations governing their dynamics.展开更多
A fluid–structure interaction method combining a nonlinear finite element algorithm with a preconditioning finite volume method is proposed in this paper to simulate parachute transient dynamics. This method uses a t...A fluid–structure interaction method combining a nonlinear finite element algorithm with a preconditioning finite volume method is proposed in this paper to simulate parachute transient dynamics. This method uses a three-dimensional membrane–cable fabric model to represent a parachute system at a highly folded configuration. The large shape change during parachute inflation is computed by the nonlinear Newton–Raphson iteration and the linear system equation is solved by the generalized minimal residual（GMRES） method. A membrane wrinkling algorithm is also utilized to evaluate the special uniaxial tension state of membrane elements on the parachute canopy. In order to avoid large time expenses during structural nonlinear iteration, the implicit Hilber–Hughes–Taylor（HHT） time integration method is employed. For the fluid dynamic simulations, the Roe and HLLC（Harten–Lax–van Leer contact） scheme has been modified and extended to compute flow problems at all speeds. The lower–upper symmetric Gauss–Seidel（LUSGS） approximate factorization is applied to accelerate the numerical convergence speed. Finally,the test model of a highly folded C-9 parachute is simulated at a prescribed speed and the results show similar characteristics compared with experimental results and previous literature.展开更多
This article lays out a unified theory for dynamics of vehicle-pavement interaction under moving and stochastic loads. It covers three major aspects of the subject： pavement surface, tire-pavement contact forces, and...This article lays out a unified theory for dynamics of vehicle-pavement interaction under moving and stochastic loads. It covers three major aspects of the subject： pavement surface, tire-pavement contact forces, and response of continuum media under moving and stochastic vehicular loads. Under the subject of pavement surface, the spectrum of thermal joints is analyzed using Fourier analysis of periodic function. One-dimensional and two-dimensional random field models of pavement surface are discussed given three different assumptions. Under the subject of tire-pavement contact forces, a vehicle is modeled as a linear system. At a constant speed of travel, random field of pavement surface serves as a stationary stochastic process exciting vehicle vibration, which, in turn, generates contact force at the interface of tire and pavement. The contact forces are analyzed in the time domain and the frequency domains using random vibration theory. It is shown that the contact force can be treated as a nonzero mean stationary process with a normal distribution. Power spectral density of the contact force of a vehicle with walking-beam suspension is simulated as an illustration. Under the subject of response of continuum media under moving and stochastic vehicular loads, both time-domain and frequency-domain analyses are presented for analytic treatment of moving load problem. It is shown that stochastic response of linear continuum media subject to a moving stationary load is a nonstationary process. Such a nonstationary stochastic process can be converted to a stationary stochastic process in a follow-up moving coordinate.展开更多
This research work is related to soliton solutions considered as models that can describe the complex configuration of elementary particles from the study of the interactions of their fields. It is interested in the i...This research work is related to soliton solutions considered as models that can describe the complex configuration of elementary particles from the study of the interactions of their fields. It is interested in the interaction of fields between two different elementary particles by expressing their physical properties. For that, we have obtained, exact static plane symmetric soliton-like solutions to the nonlinear equations of interacting electromagnetic and scalar fields taking into account the own gravitational field of elementary particles using the calibrated invariance function <i>P</i>(<i>I</i>). It has been proved that all solutions of the Einstein, nonlinear electromagnetic and scalar field equations are regular with the localized energy density. Moreover, the total charge of particles is finite and the total energy of the interaction fields is bounded. It have been emphasized the importance to the own gravitational field of elementary particles and the role of the nonlinearity of fields in the determination of these solutions. In flat space-time, soliton-like solutions exist but the total energy of the interaction fields is equal to zero. We have also shown that in the linear case, soliton-like solutions are absent.展开更多
In neurons and myocytes,selective ion channels in the plasma membrane play a pivotal role in transducing chemical or sensory stimuli into electrical signals,underpinning neural and cardiac functionality.Recent advance...In neurons and myocytes,selective ion channels in the plasma membrane play a pivotal role in transducing chemical or sensory stimuli into electrical signals,underpinning neural and cardiac functionality.Recent advancements in biomedical research have increasingly spotlighted the interaction between ion channels and electromagnetic fields,especially terahertz(THz)radiation.This review synthesizes current findings on the impact of THz radiation,known for its deep penetration and non-ionizing properties,on ion channel kinetics and membrane fluid dynamics.It is organized into three parts:the biophysical effects of THz exposure on cells,the specific modulation of ion channels by THz radiation,and the potential pathophysiological consequences of THz exposure.Understanding the biophysical mechanisms underlying these effects could lead to new therapeutic strategies for diseases.展开更多
Based on the atom-cavity-field interaction, this paper proposes a scheme for the teleportation of a bipartite entangled coherent state （ECS） with high fidelity as long as │α│ is not too small. In this proposal, o...Based on the atom-cavity-field interaction, this paper proposes a scheme for the teleportation of a bipartite entangled coherent state （ECS） with high fidelity as long as │α│ is not too small. In this proposal, only four cavities and a three-level cascade atom are needed. The fidelity of the ECS is calculated and analysed in detail.展开更多
Proposal for the teleportation of two-atom state is presented. It is based on the simultaneous interaction of two two-level atoms with a single-mode cavity with a filed of n photons. In the proposed scheme, two pairs ...Proposal for the teleportation of two-atom state is presented. It is based on the simultaneous interaction of two two-level atoms with a single-mode cavity with a filed of n photons. In the proposed scheme, two pairs of EPR state are used as quantum channel to teleport an unknown two-atom state. The completed time is greatly reduced and cavity field is not required to be detected are shown to be the distinct features of the presented scheme.展开更多
The quantitative structure-activity relationship （QSAR） of 30 acylthiourea analogues was studied by using a three-dimensional holographic vector of atomic interaction field （3D-HoVAIF） to describe their chemical s...The quantitative structure-activity relationship （QSAR） of 30 acylthiourea analogues was studied by using a three-dimensional holographic vector of atomic interaction field （3D-HoVAIF） to describe their chemical structures. The descriptors obtained were screened by stepwise multiple regression （SMR） and a partial least-squares （PLS） regression model was built. The correlation coefficient r^2 of the established model and Leave-One-Out （LOO） Cross-Validation （CV） correlation coefficient q^2 are 0.624 and 0.409, respectively. The model has favorable stability and good prediction capability, and further QSAR analysis showed that hydrophobic interaction has the most important effect on the activity of acylthiourea analogue and 3D-HoVAIF was applicable to the molecular structural characterization and biologicalactivity prediction.展开更多
A novel three-dimensional holographic vector of atomic interaction field（3D-HoVAIF） was used to describe the chemical structures of 23 benzoxazinone derivatives as antithrombotic drugs.Here a quantitative structure ...A novel three-dimensional holographic vector of atomic interaction field（3D-HoVAIF） was used to describe the chemical structures of 23 benzoxazinone derivatives as antithrombotic drugs.Here a quantitative structure activity relationship（QSAR） model was built by partial least-squares（PLS） regression.The estimation stability and prediction ability of the model were strictly analyzed by both internal and external validations.The correlation coefficients of established PLS model,leave-one-out（LOO） cross-validation,and predicted values versus experimental ones of external samples were R2=0.899,RCV2=0.854 and Qext2=0.868,respectively.These values indicated that the built PLS model had both favorable estimation stability and good prediction capabilities.Furthermore,the satisfactory results showed that 3D-HoVAIF could preferably express the information related to the biological activity of benzoxazinone derivatives.展开更多
文摘A series of magnetic properties of Tm_2Fe_(14)B are explained quantitatively by the calculations based on the single ion model. The magnetic properties include the temperature dependence of the spontaneous magnetization, the spin reorientation temperature and the magnetization curves along the principal crystal axes at 4.2, 100, 150 and 200 K. The values of the exchange field and the crystalline electric field parameters used in the calculations are μ_BH_(ex)(T=0 K)=135, B_2~0=1.77, B_2~2=±2.97, B_4~0=-3.06×10^(-3), B_4^(-2)=0, B_4~4=-6.82×10^(-3), B_6~0=1.05× 10^(-5), B_6^(-2)=±7.40×10^(-5), B_6~4=1.96×10^(-4), and B_6^(-6)=0 all in K unit. The magnetization processes of the Fe-and Tm-sublattices at different temperatures are analysed. The processes are characterized by the non-collinearity between the magnetic moments of the Fe-and Tm-sublattices.
基金supported by the National Research Foundation of Korea funded by the Korean Government(MSIT),South Korea(Grant Nos.NRF-2015R1A2A2A11000907 and NRF-2015R1A2A2A04006979)Ministry of Science and ICT(MSIT),Korea,under the Information Technology Research Center(ITRC)support program(IITP-2017-2015-0-00385),supervised by the Institute for Information and Communications Technology Promotion(IITP)
文摘The potential of bulk-like WTe2 particles for the realization of a passive Q-switch operating at the 1 μm wavelength was investigated. The WTe2 particles were prepared using a simple mechanical exfoliation method together with Scotch tape. By attaching bulk-like WTe2 particles, which remained on the top of the sticky surface of a small segment of the Scotch tape, to the flat side of a side-polished fiber, a saturable absorber（SA） was readily implemented. A strong saturable absorption was then readily obtained through an evanescent field interaction with the WTe2 particles. The modulation depth of the prepared SA was measured as ~2.18% at 1.03 μm. By incorporating the proposed SA into an all-fiberized ytterbium-doped fiber ring cavity, stable Qswitched pulses were readily achieved.
基金supported by the Ministry of Science and Technology of China (2010DFA32680)the National Natural Science Foundation of China (21005062)the Fundamental Research Funds for the Central Universities (CDJRC10220010)
文摘Three-dimensional holographic vector of atomic interaction field（3D-HoVAIF） is used to describe the chemical structures of polychlorinated naphthalenes（PCNs）.After variable screening by stepwise multiple regression（SMR） technique,the liner relationships between gas-chromatographic relative retention time（RRT）,298 K supercooled liquid pressures（logPL）,n-octanol/air partition coefficient（logKOA）,n-octanol/water partition coefficient（logKOW）,aqueous solubilities（logSW）,relative in vitro potency values（-logEROD） of PCNs and 3D-HoVAIF descriptors have been established by partial least-square（PLS） regression.The result shows that the 3D-HoVAIF descriptors can be well used to express the quantitative structure-property（activity） relationships of PCNs.Predictive capability of the models has also been demonstrated by leave-one-out cross-validation.Moreover,the predicted values have been presented for those PCNs which are lack of experimentally physico-chemical properties and biological activity by the optimum models.
基金Supported by the Fund of National High Technology Research and Development Program (863 Program, No. 2006AA02Z312)
文摘Study on the quantitative structure-activity relationship （QSAR） of 26 compounds, N-[5-（2-furanyl）-2-methyl-4-oxo-4H-thieno[2,3-d]pyrimidin-3-yl]-carboxamide and 3-substituted- 5-（2-furanyl）-2-methyl-3H-thieno[2,3-d]pyrimidin-4-ones, with three-dimensional holographic vector of atomic interaction field （3D-HoVAIF） was carried out. SMR-PLS QSAR models have been created and good correlation coefficients and cross-validated correlation coefficients were obtained. The result shows that the models have good prediction capability and favorable stability and the 3D-HoVAIF is applicable to the molecular structural characterization and biological activity prediction.
文摘The resonance interaction of two-state atoms with single mode field is described theoretically by using the semi-classical theory and Jaynes-Cummings model. The nonlinear characteristics of this system are calculated by using FFT and Runge-Kutta methods. The chaotic strange attractors in this system are obtained from the numerical results.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11204061,11374085,11104057,11274010 and 11204002the Anhui Provincial Natural Science Foundation under Grant No 1408085MA16+4 种基金the Anhui Provincial Candidates for Academic and Technical Leaders Foundation under Grant No 2015H052the Discipline Top-Notch Talents Foundationthe Excellent Young Talents Support Plan of Anhui Provincial Universitiesthe Specialized Research Fund for the Doctoral Program of Higher Education under Grant No 20113401110002the 211 Project of Anhui University,and the Personnel Department of Anhui Province
文摘We investigate the effects of pure Dzyaloshinskii Moriya （DM） interaction with magnetic field on entanglement in intrinsic decoherence, assuming that the system is initially in four Bell states ｜φ±〉 = （｜00） ± ｜11〉）/√2 and ｜ψ±〉 = （｜01） ±｜10〉）/√2, respectively. It is found that if the system is initially in the state p1（0） = ｜φ＋〉〈φ＋1, the entanglement can obtain its maximum when the DM interaction vector D is in the plane of XOZ and magnetic field B = By with the infinite time t, moreover the entanglement is independent of By and t when By is perpendicular to D. In addition, we obtain similar results when the system is initially in the states p2（0） = ｜φ-〉〈φ-｜ or p3 （0） = ｜ψ＋〉〈ψ＋1. However, we find that if the system is initially in the state P4 （0） = ｜ψ-〉〈ψ-l, the entanglement can obtain its maximum for infinite t, when the DM vector is in the plane ofYOZ, XOZ, or XOY, with the magnetic field parallel to X, Y, or Z axis, respectively. Moreover, when the axial B is perpendicular to D for the initial state p4（O）, the negativity oscillates with time t and reaches a stable value, the larger the value of B is, the greater the stable value is, and the shorter the oscillation time of the negativity is. Thus we can adjust the direction and value of the external magnetic field to obtain the maximal entanglement, and avoid the adverse effects of external environment in some initial state. This is feasible within the cun＇ent experimental technology.
基金Supported by the National Natural Science Foundation of China under Grant No 51427801
文摘We investigate spin squeezing effects of trapped ions in an off-resonance optical potential system using the arbitrary range spin spin interaction and transverse field model. The collective spin noises at any time are analyzed exactly. The general expression of spin squeezing factor is presented for arbitrary-range spin interaction. For the nearest-neighbor and next-nearest neighbor spin interaction model, the analytic solutions are reduced from the general expressions. It is shown that the maximum spin squeezing is enhanced for the general arbitrary-range spin interaction compared with the nearest-neighbor interaction model as the long-range interaction with arbitrary sites enforces stronger correlation.
文摘In this paper, the nonlinear interaction of ultra-high power laser beam with fusion plasma at relativistic regime in the presence of obliquely external magnetic field has been studied. Imposing an external magnetic field on plasma can modify the density profile of the plasma so that the thermal conductivity of electrons reduces which is considered to be the decrease of the threshold energy for ignition. To achieve the fusion of Hydrogen–Boron(HB) fuel,the block acceleration model of plasma is employed. Energy production by HB isotopes can be of interest, since its reaction does not generate radioactive tritium. By using the inhibit factor in the block model acceleration of plasma and Maxwell's as well as the momentum transfer equations, the electron density distribution and dielectric permittivity of the plasma medium are obtained. Numerical results indicate that with increasing the intensity of the external magnetic field, the oscillation of the laser magnetic field decreases, while the dielectric permittivity increases. Moreover, the amplitude of the electron density becomes highly peaked and the plasma electrons are strongly bunched with increasing the intensity of external magnetic field. Therefore, the magnetized plasma can act as a positive focusing lens to enhance the fusion process. Besides, we find that with increasing θ-angle(from oblique external magnetic field) between 0 and 90°, the dielectric permittivity increases, while for θ between 90° and 180°, the dielectric permittivity decreases with increasing θ.
文摘Studying the two famous old problems that why the moon can move around the Sun and why the orbit of the Moon around the Earth cannot be broken off by the Sun under the condition calculating with <em>F</em>=<em>GMm</em>/<em>R</em><sup>2</sup>, the attractive force of the Sun on the Moon is almost 2.2 times that of the Earth, we found that the planet and moon are unified as one single gravitational unit which results in that the Sun cannot have the force of <em style="white-space:normal;">F</em><span style="white-space:normal;">=</span><em style="white-space:normal;">GMm</em><span style="white-space:normal;">/</span><em style="white-space:normal;">R</em><sup style="white-space:normal;">2</sup> on the moon. The moon is moved by the gravitational unit orbiting around the Sun. It could indicate that the gravitational field of the moon is limited inside the unit and the gravitational fields of both the planet and moon are unified as one single field interacting with the Sun. The findings are further clarified by reestablishing Newton’s repulsive gravity.
文摘QED(quantum electrodynamics)is the QFT(quantum field theory)describing the interaction between light and matter.While conventional QED is based on TEM(transverse electromagnetic)waves,there has been increasing interest in the theoretical and experimental exploration of LSW(longitudinal scalar waves)solutions that are often omitted in CED(classical electrodynamics)but may have physical significance in nontrivial vacuum conditions.This paper delves into the theoretical foundation of LSW,their role in QED,and the associated mathematical equations governing their dynamics.
文摘A fluid–structure interaction method combining a nonlinear finite element algorithm with a preconditioning finite volume method is proposed in this paper to simulate parachute transient dynamics. This method uses a three-dimensional membrane–cable fabric model to represent a parachute system at a highly folded configuration. The large shape change during parachute inflation is computed by the nonlinear Newton–Raphson iteration and the linear system equation is solved by the generalized minimal residual（GMRES） method. A membrane wrinkling algorithm is also utilized to evaluate the special uniaxial tension state of membrane elements on the parachute canopy. In order to avoid large time expenses during structural nonlinear iteration, the implicit Hilber–Hughes–Taylor（HHT） time integration method is employed. For the fluid dynamic simulations, the Roe and HLLC（Harten–Lax–van Leer contact） scheme has been modified and extended to compute flow problems at all speeds. The lower–upper symmetric Gauss–Seidel（LUSGS） approximate factorization is applied to accelerate the numerical convergence speed. Finally,the test model of a highly folded C-9 parachute is simulated at a prescribed speed and the results show similar characteristics compared with experimental results and previous literature.
基金sponsored in part by the National Science Foundationby National Natural Science Foundation of China+1 种基金by Ministry of Communication of Chinaby Jiangsu Natural Science Foundation
文摘This article lays out a unified theory for dynamics of vehicle-pavement interaction under moving and stochastic loads. It covers three major aspects of the subject： pavement surface, tire-pavement contact forces, and response of continuum media under moving and stochastic vehicular loads. Under the subject of pavement surface, the spectrum of thermal joints is analyzed using Fourier analysis of periodic function. One-dimensional and two-dimensional random field models of pavement surface are discussed given three different assumptions. Under the subject of tire-pavement contact forces, a vehicle is modeled as a linear system. At a constant speed of travel, random field of pavement surface serves as a stationary stochastic process exciting vehicle vibration, which, in turn, generates contact force at the interface of tire and pavement. The contact forces are analyzed in the time domain and the frequency domains using random vibration theory. It is shown that the contact force can be treated as a nonzero mean stationary process with a normal distribution. Power spectral density of the contact force of a vehicle with walking-beam suspension is simulated as an illustration. Under the subject of response of continuum media under moving and stochastic vehicular loads, both time-domain and frequency-domain analyses are presented for analytic treatment of moving load problem. It is shown that stochastic response of linear continuum media subject to a moving stationary load is a nonstationary process. Such a nonstationary stochastic process can be converted to a stationary stochastic process in a follow-up moving coordinate.
文摘This research work is related to soliton solutions considered as models that can describe the complex configuration of elementary particles from the study of the interactions of their fields. It is interested in the interaction of fields between two different elementary particles by expressing their physical properties. For that, we have obtained, exact static plane symmetric soliton-like solutions to the nonlinear equations of interacting electromagnetic and scalar fields taking into account the own gravitational field of elementary particles using the calibrated invariance function <i>P</i>(<i>I</i>). It has been proved that all solutions of the Einstein, nonlinear electromagnetic and scalar field equations are regular with the localized energy density. Moreover, the total charge of particles is finite and the total energy of the interaction fields is bounded. It have been emphasized the importance to the own gravitational field of elementary particles and the role of the nonlinearity of fields in the determination of these solutions. In flat space-time, soliton-like solutions exist but the total energy of the interaction fields is equal to zero. We have also shown that in the linear case, soliton-like solutions are absent.
基金support from the Science and Technology Innovation 2030-Brain Science and Brain-Inspired Intelligence Project(2021ZD0201301 and 2021ZD0200204)and STI2030-Major Projects(2021ZD0202500)the National Natural Science Foundation of China(U20A20221,32130044,T2241002,32200807)+1 种基金the Shanghai Municipal Science and Technology Major Project(2018SHZDZX01 and 2021SHZDZX0103)ZJLab,Shanghai Municipal Science and Technology Committee of Shanghai outstanding academic leaders plan(21XD1400400,21XD1400100).
文摘In neurons and myocytes,selective ion channels in the plasma membrane play a pivotal role in transducing chemical or sensory stimuli into electrical signals,underpinning neural and cardiac functionality.Recent advancements in biomedical research have increasingly spotlighted the interaction between ion channels and electromagnetic fields,especially terahertz(THz)radiation.This review synthesizes current findings on the impact of THz radiation,known for its deep penetration and non-ionizing properties,on ion channel kinetics and membrane fluid dynamics.It is organized into three parts:the biophysical effects of THz exposure on cells,the specific modulation of ion channels by THz radiation,and the potential pathophysiological consequences of THz exposure.Understanding the biophysical mechanisms underlying these effects could lead to new therapeutic strategies for diseases.
文摘Based on the atom-cavity-field interaction, this paper proposes a scheme for the teleportation of a bipartite entangled coherent state （ECS） with high fidelity as long as │α│ is not too small. In this proposal, only four cavities and a three-level cascade atom are needed. The fidelity of the ECS is calculated and analysed in detail.
文摘Proposal for the teleportation of two-atom state is presented. It is based on the simultaneous interaction of two two-level atoms with a single-mode cavity with a filed of n photons. In the proposed scheme, two pairs of EPR state are used as quantum channel to teleport an unknown two-atom state. The completed time is greatly reduced and cavity field is not required to be detected are shown to be the distinct features of the presented scheme.
基金supported by the National High-tech Research Program (the "863" Program, No. 2006AA02Z312)Innovative Group Program for Graduates of Chongqing University, Science and Innovation Fund (No. 200711C1A0010260)
文摘The quantitative structure-activity relationship （QSAR） of 30 acylthiourea analogues was studied by using a three-dimensional holographic vector of atomic interaction field （3D-HoVAIF） to describe their chemical structures. The descriptors obtained were screened by stepwise multiple regression （SMR） and a partial least-squares （PLS） regression model was built. The correlation coefficient r^2 of the established model and Leave-One-Out （LOO） Cross-Validation （CV） correlation coefficient q^2 are 0.624 and 0.409, respectively. The model has favorable stability and good prediction capability, and further QSAR analysis showed that hydrophobic interaction has the most important effect on the activity of acylthiourea analogue and 3D-HoVAIF was applicable to the molecular structural characterization and biologicalactivity prediction.
基金supported by the Natural Science Foundation of Shaanxi Province (2009JQ2005)Foundation of Educational Commission of Shaanxi Province (09JK358) Graduate Innovation Fund of Shaanxi University of Science and Technology
文摘A novel three-dimensional holographic vector of atomic interaction field（3D-HoVAIF） was used to describe the chemical structures of 23 benzoxazinone derivatives as antithrombotic drugs.Here a quantitative structure activity relationship（QSAR） model was built by partial least-squares（PLS） regression.The estimation stability and prediction ability of the model were strictly analyzed by both internal and external validations.The correlation coefficients of established PLS model,leave-one-out（LOO） cross-validation,and predicted values versus experimental ones of external samples were R2=0.899,RCV2=0.854 and Qext2=0.868,respectively.These values indicated that the built PLS model had both favorable estimation stability and good prediction capabilities.Furthermore,the satisfactory results showed that 3D-HoVAIF could preferably express the information related to the biological activity of benzoxazinone derivatives.
