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NeoMinkowskian Cosmological Black Hole, Poincaré’s Gravific Electron and Density of CBR
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作者 Yves Pierseaux 《Journal of Modern Physics》 2020年第2期237-280,共44页
In the previous paper (JMP 2014) we showed that there exists a NeoMinkowskian Gravitational Expanding Solution of GR (General Relativity) with CC (Cosmological Constant). We prove now that NeoMinkowskian Vacuum (non-b... In the previous paper (JMP 2014) we showed that there exists a NeoMinkowskian Gravitational Expanding Solution of GR (General Relativity) with CC (Cosmological Constant). We prove now that NeoMinkowskian Vacuum (non-baryonic Fluid), with gravitational (first) density (dark energy) and gravitational waves (at light speed), corresponds to the Gravitation Field of a Cosmological Black Hole (CBH). The latter predicts furthermore a basic emission of Radiation (CBR) from Hubble spherical singular Horizon to the inside of CBH (unlike Hawking’s emission) at an initial singular time. Our solution is then compatible with a well-tempered Big Bang and Expanding Universe (Escher’s Figure, see Penrose, 3) but incompatible with inflation. The latter is based on Hypothesis of a so-called Planck’s particle (Lemaitre’s primitive atom) characterized by a so-called Planck length. We prove that we can short-circuit this unstable particle with a stable cosmological Poincaré’s electron with gravific pressure. It is well known that electron is a stranger in usual Minkowskian vacuum (dixit Einstein). The stranger electron can be perfectly integrated in NeoMinkowskian Radiation fluid and then also (with its mass, charge and wavelength) in (second density of) CBR. Everything happens as if the leptonic mass of the electron were induced by our cosmological field. The unexpected cosmological model proposed here is the only one that predicts numerical values of (second) density and temperature of CBR very close to the observed (COBE) values. 展开更多
关键词 COSMOLOGICAL Constant General Relativity Minkowskian Metric Cosmolog-ical Black Hole Tachyons Hyperbolic Horizon density of Vacuum density of CBR Poincarés Gravitational Waves Poincarés ELECTRON DE Broglies Wave Electrodynamics DE Broglies Subquantum Substratum
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First-principles prediction of shock Hugoniot curves of boron,aluminum,and silicon from stochastic density functional theory
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作者 Tao Chen Qianrui Liu +1 位作者 Chang Gao Mohan Chen 《Matter and Radiation at Extremes》 2025年第5期73-83,共11页
By adopting stochastic density functional theory(SDFT)and mixed stochastic-deterministic density functional theory(MDFT)methods,we perform first-principles calculations to predict the shock Hugoniot curves of boron(pr... By adopting stochastic density functional theory(SDFT)and mixed stochastic-deterministic density functional theory(MDFT)methods,we perform first-principles calculations to predict the shock Hugoniot curves of boron(pressure P=7.9×10^(3)-1.6×10^(6) GPa and temperature T=25-2800 eV),silicon(P=2.6×10^(3)-7.9×10^(5) GPa and T=21.5-1393 eV),and aluminum(P=5.2×10^(3)-9.0×10^(5) GPa and T=25-1393 eV)over wide ranges of pressure and temperature.In particular,we systematically investigate the impact of different cutoff radii in norm-conserving pseudopotentials on the calculated properties at elevated temperatures,such as pressure,ionization energy,and equation of state.By comparing the SDFT and MDFT results with those of other first-principles methods,such as extended first-principles molecular dynamics and path integral Monte Carlo methods,we find that the SDFT and MDFT methods show satisfactory precision,which advances our understanding of first-principles methods when applied to studies of matter at extremely high pressures and temperatures. 展开更多
关键词 mixed stochastic deterministic density functional theory BORON shock hugoniot curves stochastic density functional theory stochastic density functional theory sdft ALUMINUM SILICON first principles calculations
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Ultrafast Laser Energy Density and Retinal Absorption Cross-Section Determination by Saturable Absorption Measurements
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作者 Alfons Penzkofer Meike Luck +1 位作者 Tilo Mathes Peter Hegemann 《Journal of Analytical Sciences, Methods and Instrumentation》 2014年第1期19-26,共8页
Laser pulse nonlinear transmission measurements through saturable absorbers of known absorption parameters allow the measurement of their energy density. On the other hand, nonlinear transmission measurements of laser... Laser pulse nonlinear transmission measurements through saturable absorbers of known absorption parameters allow the measurement of their energy density. On the other hand, nonlinear transmission measurements of laser pulses of known energy density through absorbing media allow their absorption parameter determination. The peak energy density w0P of second harmonic pulses of a mode-locked titanium sapphire laser at wavelength λP = 400 nm is determined by nonlinear energy transmission measurement TE through the dye ADS084BE (1,4-bis(9-ethyl-3-car-bazovinylene)-2-methoxy-5-(2’-ethyl-hexyloxy)-benzene) in tetrahydrofuran. TE(w0P) calibration curves are calculated for laser pulse peak energy density reading w0P from measured pulse energy transmissions TE. The ground-state absorption cross-section σP and the excited-state absorption cross-section σex at λP, and the number density N0 of the retinal Schiff base isoform RetA in pH 7.4 buffer of the blue-light adapted recombinant rhodopsin fragment of the histidine kinase rhodopsin HKR1 from Chlamydomonas reinhardtii were determined by picosecond titanium sapphire second harmonic laser pulse energy transmission measurement TE through RetA as a function of laser input peak energy density w0P. The complete absorption cross-section spectrum 展开更多
关键词 Laser Pulse Peak Energy density DETERMINATION Ground-State ABSORPTION CROSS-SECTION DETERMINATION Excited-State ABSORPTION CROSS-SECTION DETERMINATION Saturable ABSORPTION ADS084BE Dye Histidine Kinase RHODOPSIN HKR1 RETINAL Schiff Base RetA Cofactor Number density DETERMINATION
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Infrared small target detection based on density peaks searching and weighted multi-feature local difference
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作者 JI Bin FAN Pengxiang +2 位作者 WANG Mengli LIU Yang XU Jiafeng 《Optoelectronics Letters》 2025年第4期218-225,共8页
To address the issues of unknown target size,blurred edges,background interference and low contrast in infrared small target detection,this paper proposes a method based on density peaks searching and weighted multi-f... To address the issues of unknown target size,blurred edges,background interference and low contrast in infrared small target detection,this paper proposes a method based on density peaks searching and weighted multi-feature local difference.Firstly,an improved high-boost filter is used for preprocessing to eliminate background clutter and high-brightness interference,thereby increasing the probability of capturing real targets in the density peak search.Secondly,a triple-layer window is used to extract features from the area surrounding candidate targets,addressing the uncertainty of small target sizes.By calculating multi-feature local differences between the triple-layer windows,the problems of blurred target edges and low contrast are resolved.To balance the contribution of different features,intra-class distance is used to calculate weights,achieving weighted fusion of multi-feature local differences to obtain the weighted multi-feature local differences of candidate targets.The real targets are then extracted using the interquartile range.Experiments on datasets such as SIRST and IRSTD-IK show that the proposed method is suitable for various complex types and demonstrates good robustness and detection performance. 展开更多
关键词 extract featur background clutter density peaks searching infrared small target detection weighted multi feature local difference capturing real targets density peak infrared small target detectionthis
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Applying the Liouville–Lanczos method of time-dependent density-functional theory to warm dense matter
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作者 Zhandos A.Moldabekov Sebastian Schwalbe +3 位作者 Thomas Gawne Thomas R.Preston Jan Vorberger Tobias Dornheim 《Matter and Radiation at Extremes》 2025年第4期44-57,共14页
Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instr... Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instrument function,is measured in X-ray Thom-son scattering(XRTS)experiments,which allow the study of electronic structure properties at the microscopic level.Among the various ab initio methods,linear-response time-dependent density-functional theory(LR-TDDFT)is a key framework for simulating the DSF.The standard approach in LR-TDDFT for computing the DSF relies on the orbital representation.A significant drawback of this method is the unfavorable scaling of the number of required empty bands as the wavenumber increases,making LR-TDDFT impractical for modeling XRTS measurements over large energy scales,such as in backward scattering geometry.In this work,we consider and test an alternative approach to LR-TDDFT that employs the Liouville–Lanczos(LL)method for simulating the DSF of WDM.This approach does not require empty states and allows the DSF at large momentum transfer values and over a broad frequency range to be accessed.We compare the results obtained from the LL method with those from the solution of Dyson’s equation using the standard LR-TDDFT within the projector augmented-wave formalism for isochorically heated aluminum and warm dense hydrogen.Additionally,we utilize exact path integral Monte Carlo results for the imaginary-time density-density correlation function(ITCF)of warm dense hydrogen to rigorously benchmark the LL approach.We discuss the application of the LL method for calculating DSFs and ITCFs at different wavenumbers,the effects of pseudopotentials,and the role of Lorentzian smearing.The successful validation of the LL method under WDM conditions makes it a valuable addition to the ab initio simulation landscape,supporting experimental efforts and advancing WDM theory. 展开更多
关键词 ab initio dynamic structure factors dsf Liouville Lanczos method simulating ds ab initio methodslinear response warm dense matter time dependent density functional theory density response properties
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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A Combined Heterotic String and Kähler Manifold Elucidation of Ordinary Energy,Dark Matter,Olbers’s Paradox and Pure Dark Energy Density of the Cosmos
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作者 Mohamed S.El Naschie 《Journal of Modern Physics》 2017年第7期1101-1118,共18页
We utilize the topological-geometrical structure imposed by the Heterotic superstring theory on spacetime in conjunction with the K3 K&auml;hler manifold to explain the mysterious nature of dark matter and its cou... We utilize the topological-geometrical structure imposed by the Heterotic superstring theory on spacetime in conjunction with the K3 K&auml;hler manifold to explain the mysterious nature of dark matter and its coupling to the pure dark energy density of the cosmos. The analogous situations in the case of a Kerr black hole as well as the redundant components of the Riemannian tensor are pointed out and the final result was found to be in complete agreement with all previous theoretical ones as well as all recent accurate measurements and cosmic observations. We conclude by commenting briefly on the Cantorian model of Zitterbewegung and the connection between Olbers’s paradox and dark energy. 展开更多
关键词 Heterotic Strings K3 Kahler Manifold Dark Matter Pure Heterotic Dark Energy Einsteins Relativity Accelerated Cosmic Expansion Negative Gravity Fractal Spacetime E-Infinity Theory Kerr Black Holes Geometry Kaluza-Klein Theory Dvoretzkys Theorem Empty Set Zero Set Connes Noncommutative Geometry tHooft Renormalon STATE Vector Reduction density Matrix tHooft Fractal Spacetime Transfinite Cellular Automata Interpretation of Quantum Mechanics ZITTERBEWEGUNG Olberss Dark Sky Paradox
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Large-angle stimulated Raman scattering induced by transverse density modulation
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作者 Z.M.Huang Qing Wang +12 位作者 R.J.Cheng X.X.Li S.Y.Lv D.J.Liu Z.Y.Xu S.T.Zhang Z.J.Chen Qiang Wang C.Z.Xiao Z.J.Liu L.H.Cao C.Y.Zheng X.T.He 《Matter and Radiation at Extremes》 2025年第5期64-72,共9页
Large-angle stimulated Raman scattering(LA-SRS)in a longitudinally inhomogeneous plasma with a transverse density modulation is studied using a three-wave coupled model and numerical simulations.The simulations show t... Large-angle stimulated Raman scattering(LA-SRS)in a longitudinally inhomogeneous plasma with a transverse density modulation is studied using a three-wave coupled model and numerical simulations.The simulations show that the scattering angle of SRS in a longitudinally inhomogeneous plasma can be significantly affected by transverse density modulation.Under transverse density modulation conditions,the laser focuses into underdense regions,owing to the transversely modulated refractive index.The angle of LA-SRS,neither a purely 90° angle side scattering nor purely backscattering,is almost consistent with the specific angle at which the density inhomogeneity vanishes.In modulated plasmas,the nonuniform distribution of laser intensity shifts the regions of scattering and gain compared with those in uniform plasmas,ultimately affecting the laser transmission.SRS is suppressed in weakly modulated regimes,whereas it is enhanced under strong modulation conditions,and a theoretical criterion distinguishing between strong and weak modulation is established. 展开更多
关键词 longitudinally inhomogeneous plasma transverse density modulation numerical simulationsthe transversely modulated refractive indexthe large angle stimulated Raman scattering three wave coupled model transverse density modulationunder
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Research Progress in the Polymeric Nitrogen with High Energy Density
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作者 Jie Zhang Guo Chen +2 位作者 Chengfeng Zhang Yuxuan Xu Xianlong Wang 《Chinese Physics Letters》 2025年第5期69-79,共11页
Polymeric nitrogen is a potential high-energy-density material with the advantages of high energy density, easy availability of raw materials, and non-pollution. The design and synthesis of polymeric nitrogen are impo... Polymeric nitrogen is a potential high-energy-density material with the advantages of high energy density, easy availability of raw materials, and non-pollution. The design and synthesis of polymeric nitrogen are important in the research field of energetic materials. The cubic gauche nitrogen was successfully synthesized at high pressure in the diamond anvil cell, which stimulated the theoretical and experimental investigations. To date, several hundred kinds of polymeric nitrogen have been reported. This review introduces the progressive development of polymeric nitrogen with high energy density, the challenges faced by the synthesized polymeric nitrogen under high-pressure,and the importance to improve the stability of polymeric nitrogen at ambient pressure. Furthermore, alternative methods for synthesizing polymeric nitrogen under moderate conditions are also presented. In this field, more efforts are needed to develop strategies for stabilizing more polymeric nitrogen to ambient conditions, especially the stability of free surfaces. 展开更多
关键词 polymeric nitrogen cubic gauche nitrogen theoretical experimental investigations energetic materials raw materials design synthesis high energy density diamond anvil cell
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Corrigendum to“Evolution of multi-cluster fracturing in high-density layered shale considering the effect of injection scheme”[Pet.Sci.22(2025)2109-2122]
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作者 Xiao Yan Haitao Yu Peng Zhang 《Petroleum Science》 2025年第7期3068-3068,共1页
The authors regret Acknowledgements Firstly,the authors wish to acknowledge the academic support from Ruhr University Bochum during the first author's(Xiao Yan)research stay from 2018.11 to 2020.10,including the s... The authors regret Acknowledgements Firstly,the authors wish to acknowledge the academic support from Ruhr University Bochum during the first author's(Xiao Yan)research stay from 2018.11 to 2020.10,including the soft code implement and debug support from Vladislav Gudzulic and academic advising from Günther Meschke. 展开更多
关键词 research stay academic advising soft code implement debug support high density layered shale evolution injection scheme academic support multi cluster fracturing
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Interplay of Charge Density Wave and Magnetism on the Kagomé Lattice
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作者 Yu-Han Lin Jin-Wei Dong +3 位作者 Ruiqing Fu Xianxin Wu Ziqiang Wang Sen Zhou 《Chinese Physics Letters》 2025年第8期230-241,共12页
Motivated by the recent discovery of charge density wave(CDW)order in the magnetic kagomémetal Fe Ge,we study the single-orbital t-N-V_(1)-V_(2)model on the kagomélattice,where N,V_(1),and V_(2)are the onsit... Motivated by the recent discovery of charge density wave(CDW)order in the magnetic kagomémetal Fe Ge,we study the single-orbital t-N-V_(1)-V_(2)model on the kagomélattice,where N,V_(1),and V_(2)are the onsite,nearest neighbor,and next-nearest-neighbor Coulomb interactions,respectively.When the Fermi level lies in the flat band,the instability toward ferromagnetic(FM)order gives rise to a FM half-metal at sufficiently large onsite N.Intriguingly,at band filling n=17/24,the Fermi level crosses the van Hove singularity of the spin-minority bands of the half-metal.We show that,due to the unique geometry and sublattice interference on the kagomélattice at van Hove singularity,the inter-site Coulomb interactions V_(1) and V_(2)drive a real and an imaginary bond-ordered 2a_(0)×2a_(0) CDW instability,respectively.The FM loop current CDW with complex bond orders is a spin-polarized Chern insulator exhibiting the quantum anomalous Hall effect.The bond fluctuations are found to be substantially enhanced compared to the corresponding nonmagnetic kagomémetals at van Hove filling,providing a concrete model realization of the bond-ordered CDWs,including the FM loop current CDW,over the onsite charge density ordered states.When the spins are partially polarized at an intermediate N,we find that the interplay of CDW and magnetism enables the formation of real and complex bond-ordered CDWs,and the CDW transition is accompanied by a substantial enhancement in the ordered magnetic moments.These findings provide physical insights for the emergence of 2a_(0)×2a_(0) CDWs and their interplay with magnetism on the kagomélattice,and capture the essential physics observed experimentally in Fe Ge. 展开更多
关键词 half metal Van Hove singularity kagom metal fe gewe MAGNETISM ferromagnetic order charge density wave kagom lattice fermi level crosses van hove sing
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Anode-Free Design with Pelletized Aluminium Current Collector Enables High-Energy-Density Sodium All-Solid-State Batteries
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作者 Xingshu Liao Dan Liu Jinping Liu 《Energy & Environmental Materials》 2025年第3期1-3,共3页
A commentary on an anode-free cell design with electrochemically stable sodium borohydride solid electrolyte and pelletized aluminium current collector for sodium all-solid-state batteries is presented.First,the viabl... A commentary on an anode-free cell design with electrochemically stable sodium borohydride solid electrolyte and pelletized aluminium current collector for sodium all-solid-state batteries is presented.First,the viable strategies for implementing anode-free configuration utilizing solid-state electrolytes are briefly reviewed.Then,the remarkable work of Meng et al.on designing an anode-free sodium all-solid-state battery is elucidated.Finally,the significance of Meng’s work is discussed. 展开更多
关键词 pelletized aluminum current collector high energy density sodium all solid state batteries sodium borohydride solid electrolyte electrochemical stability pelletized aluminium current collector electrochemically stable sodium borohydride solid electrolyte anode free design sodium all solid state batteries
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Crustal density structure of the southern segment of the Liaocheng-Lankao fault, China 被引量:1
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作者 Lei Jiang Lanbo Liu +4 位作者 Zhiping Xu Xiaoguo Deng Lipu Yang Wei Xiong Shunqiang Xu 《Geodesy and Geodynamics》 2019年第5期347-355,共9页
The 1:200,000 middle-large scale Bouguer gravity anomaly data covering the southern segment of the Liaocheng-Lankao fault(SLLF)and its vicinity are analyzed with two methods.First,the Bouguer gravity anomaly data are ... The 1:200,000 middle-large scale Bouguer gravity anomaly data covering the southern segment of the Liaocheng-Lankao fault(SLLF)and its vicinity are analyzed with two methods.First,the Bouguer gravity anomaly data are decomposed by two-dimensional(2 D)wavelet to make the family of multi-scale modes correspond with density structure at different depths.Second,a two and half dimension(2.5 D)human-computer interaction inversion of the Bouguer gravity anomaly data are conducted with the constraints provided by two deep seismic sounding profiles(DSS1 and DSS2)crossing the study area to get the crustal density profiles.Based on the integrated study,we can draw the following conclusions:1)SLLF appears to be a deep fault with almost vertical dipping and rooted into the uppermost mantle;2)In the middle to upper crust SLLF shows an clear turning patterns and segmentation features;3)In the study area the epicentral distributions of the precisely re-located small earthquakes and the historical large earthquakes have a good correspondence with the turning patterns and segmentation features of SLLF;and 4)The results of the horizontal slices from 2 D wavelet decomposition show that there are significant differences in the density structure on the two sides of the fault.A well-defined concave structure with low density exists in the upper crust of the Dongming Depression on the west side of the fault,with the concave center being estimated at a depth of about 8 km.In contrast,the upper crust on the east side presents a relative thinner pattern in depth with a bit higher density.Meanwhile,the low-density structure in the middle crust underneath the fault is presumably caused by the uplift of the upper mantle materials and their intrusion along the deep rupture system.This paper clarified the inconsistency of fault system and epicenters of small earthquakes from upper to lower crust.The results indicated that the fault system plays an important governing role to the seismicity in this area. 展开更多
关键词 Southern SEGMENT of the Liaocheng-Lankao fault(SLLF) Bouguer gravity ANOMALIES density structure Dongming depression MULTI-SCALE wavelet decomposition Epicenters of small EARTHQUAKES
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The Pursuit of Fallacy in Density Functional Theory: The Quest for Exchange and Correlation, the Rigorous Treatment of Exchange in the Kohn-Sham Formalism and the Continuing Search for Correlation
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作者 A. Gonis 《World Journal of Condensed Matter Physics》 2014年第3期200-225,共26页
As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arb... As pointed out in the paper preceding this one, in the case of functionals whose independent variable must obey conditions of integral normalization, conventional functional differentiation, defined in terms of an arbitrary test function, is generally inapplicable and functional derivatives with respect to the density must be evaluated through the alternative and widely used limiting procedure based on the Dirac delta function. This leads to the determination of the rate of change of the dependent variable with respect to its independent variable at each isolated pair, , that may not be part of a functional (a set of ordered pairs). This extends the concept of functional derivative to expectation values of operators with respect to wave functions leading to a density even if the wave functions (and expectation values) do not form functionals. This new formulation of functional differentiation forms the basis for the study of the mathematical integrity of a number of concepts in density functional theory (DFT) such as the existence of a universal functional of the density, of orbital-free density functional theory, the derivative discontinuity of the exchange and correlation functional and the extension of DFT to open systems characterized by densities with fractional normalization. It is shown that no universal functional exists but, rather, a universal process based only on the density and independent of the possible existence of a potential, leads to unique functionals of the density determined through the minimization procedure of the constrained search. The mathematical integrity of two methodologies proposed for the treatment of the Coulomb interaction, the self-interaction free method and the optimized effective potential method is examined and the methodologies are compared in terms of numerical calculations. As emerges from this analysis, the optimized effective potential method is found to be numerically approximate but formally invalid, contrary to the rigorously exact results of the self-interaction-free method. 展开更多
关键词 density FUNCTIONAL THEORY Variational Properties of density FUNCTIONAL THEORY Self-Interaction Error Optimized Effective Potential FUNCTIONAL DERIVATIVE Parametric DERIVATIVE FUNCTIONAL Rate of Change DERIVATIVE Discontinuity Orbital-Free density FUNCTIONAL THEORY EXCHANGE and CORRELATION FUNCTIONAL
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Optical signal characteristics analysis of atmospheric disturbance density fields generated by high-speed aircraft 被引量:1
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作者 Yuyao WANG Xiaobing SUN +6 位作者 Yanli Qiao Wenyu CUI Yuan HU Changping YU Xiao LIU Honglian HUANG Rufang TI 《Chinese Journal of Aeronautics》 2025年第5期377-393,共17页
Aircraft disturbs the adjacent atmospheric environment in flight,forming spatial distribution features of atmospheric density that differ from the natural background,which may potentially be utilized as tracer charact... Aircraft disturbs the adjacent atmospheric environment in flight,forming spatial distribution features of atmospheric density that differ from the natural background,which may potentially be utilized as tracer characteristics to introduce new technologies for indirectly sensing the presence of aircraft.In this paper,the concept of a long-range aircraft detection based on the atmospheric disturbance density field is proposed,and the detection mode of tomographic imaging of the scattering light of an atmospheric disturbance flow field is designed.By modeling the spatial distribution of the disturbance density field,the scattered echo signal images of active light towards the disturbance field at long distance are simulated.On this basis,the characteristics of the disturbance optical signal at the optimal detection resolution are analyzed.The results show that the atmospheric disturbance flow field of the supersonic aircraft presents circular in the light-scattering echo images.The disturbance signal can be further highlighted by differential processing of the adjacent scattering images.As the distance behind the aircraft increases,the diffusion range of the disturbance signal increases,and the signal intensity and contrast with the background decrease.Under the ground-based observation conditions of the aircraft at a height of 10000 m,a Mach number of1.6,and a detection distance of 100 km,the contrast between the disturbance signal and the back-ground was 30 d B at a distance of one time from the rear of the fuselage,and the diffusion diameter of the disturbance signal was 50 m.At a distance eight times the length of the aircraft,the contrast decreased to 10 dB,and the diameter increased to 290 m.The contrast was reduced to 3 dB at a distance nine times the length of the aircraft,and the diameter was diffused to 310 m.These results indicate the possibility of long-range aircraft detection based on the characteristics of the atmospheric density field. 展开更多
关键词 AIRCRAFT Atmospheric disturbances density fields Long-range detection Signal characteristic LIDAR Active detection
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Managing cotton canopy architecture for machine picking cotton via high plant density and plant growth retardants 被引量:1
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作者 LAKSHMANAN Sankar SOMASUNDARAM Selvaraj +4 位作者 SHRI RANGASAMI Silambiah ANANTHARAJU Pokkharu VIJAYALAKSHMI Dhashnamurthi RAGAVAN Thiruvengadam DHAMODHARAN Paramasivam 《Journal of Cotton Research》 2025年第1期102-114,共13页
Machine picking in cotton is an emerging practice in India,to solve the problems of labour shortages and production costs increasing.Cotton production has been declining in recent years;however,the high density planti... Machine picking in cotton is an emerging practice in India,to solve the problems of labour shortages and production costs increasing.Cotton production has been declining in recent years;however,the high density planting system(HDPS)offers a viable method to enhance productivity by increasing plant populations per unit area,optimizing resource utilization,and facilitating machine picking.Cotton is an indeterminate plant that produce excessive vegeta-tive growth in favorable soil fertility and moisture conditions,which posing challenges for efficient machine picking.To address this issue,the application of plant growth retardants(PGRs)is essential for controlling canopy architecture.PGRs reduce internode elongation,promote regulated branching,and increase plant compactness,making cotton plants better suited for machine picking.PGRs application also optimizes photosynthates distribution between veg-etative and reproductive growth,resulting in higher yields and improved fibre quality.The integration of HDPS and PGRs applications results in an optimal plant architecture for improving machine picking efficiency.However,the success of this integration is determined by some factors,including cotton variety,environmental conditions,and geographical variations.These approaches not only address yield stagnation and labour shortages but also help to establish more effective and sustainable cotton farming practices,resulting in higher cotton productivity. 展开更多
关键词 COTTON High density planting system Plant growth retardant Canopy management Defoliators Machine picking Yield improvement
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Analyzing Population Density Disparity in China with GIS-automated Regionalization: The Hu Line Revisited 被引量:5
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作者 WANG Fahui LIU Cuiling XU Yaping 《Chinese Geographical Science》 SCIE CSCD 2019年第4期541-552,共12页
The famous ’Hu Line’, proposed by Hu Huanyong in 1935, divided China into two regions(southeast and northwest) of comparable area size but drastically different in population. However, the classic Hu Line was derive... The famous ’Hu Line’, proposed by Hu Huanyong in 1935, divided China into two regions(southeast and northwest) of comparable area size but drastically different in population. However, the classic Hu Line was derived manually in absence of reliable census data and computational technologies of modern days. It has been subject to criticism of lack of scientific rigor and accuracy. This research uses a GIS-automated regionalization method, termed REDCAP(Regionalization with Dynamically Constrained Agglomerative Clustering and Partitioning), to reconstruct the demarcation line based on the 2010 county-level census data in China. The results show that the logarithmic transformation of population density is a better measure of attributive homogeneity in derived regions than density itself, and produces two regions of nearly identical area size and greater contrast in population. Specifically, the revised Hu Line by Hu Huanyong in 1990 had the southeast region with 94.4% of total population and 42.9% of total land, and our delineation line yields a southeast region with 97.4% population and 50.8% land. Therefore, the population density ratio of the two regions is 27.1 by our line, much higher than the ratio of 22.4 by the Hu Line, and thus outperforms the Hu Line in deriving regions of maximum density contrast with comparable area size. Furthermore, more regions are delineated to further advance our understanding of population distribution disparity in China. 展开更多
关键词 HU LINE regional population density DISPARITY GIS-automated REGIONALIZATION REDCAP (Regionalization with Dynamically Constrained Agglomerative Clustering and Partitioning) China
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Microscopic Evidence of Charge-and Spin-Density Waves in La_(3)Ni_(2)O_(7-δ)Revealed by^(139)La-NQR
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作者 Jun Luo Jie Feng +7 位作者 Gang Wang Ningning Wang Jie Dou Aifang Fang Jie Yang Jinguang Cheng Guoqing Zheng Rui Zhou 《Chinese Physics Letters》 2025年第6期216-228,共13页
The recent discovery of superconductivity in La_(3)Ni_(2)O_(7-δ)with a transition temperature Tc close to 80 K at high pressures has attracted significant attention,due particularly to a possible density wave(DW)tran... The recent discovery of superconductivity in La_(3)Ni_(2)O_(7-δ)with a transition temperature Tc close to 80 K at high pressures has attracted significant attention,due particularly to a possible density wave(DW)transition occurring near the superconducting dome.Identifying the type of DW order is crucial for understanding the origin of superconductivity in this system.However,owing to the presence of La4Ni3O10 and other intergrowth phases in La_(3)Ni_(2)O_(7-δ)samples,extracting the intrinsic information from the La_(3)Ni_(2)O_(7) phase is challenging.In this study,we employed ^(139)La nuclear quadrupole resonance(NQR)measurements to eliminate the influence of other structural phases in the sample and obtain microscopic insights into the DW transition in La_(3)Ni_(2)O_(7-δ).Below the DW transition temperature T_(DW)∼153 K,we observe a distinct splitting in the±5/2↔±7/2 transition of the NQR resonance peak at the La(2)site,while only a line broadening is seen in the±3/2↔±5/2 transition peak.Through further analysis of the spectra,we show that the line splitting is due to a unidirectional charge modulation.A magnetic line broadening is also observed below T_(DW),accompanied by a large enhancement of the spin-lattice relaxation rate,indicating the formation of magnetically ordered moments in the DW state.Our results suggest a simultaneous formation of charge-and spin-density wave orders in La_(3)Ni_(2)O_(7-δ),thereby offering critical insights into the electronic correlations in Ni-based superconductors. 展开更多
关键词 spin density wave electronic correlations SUPERCONDUCTIVITY La Ni O charge density wave NQR
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Genetic Worth Effect Models for Boreal Conifers and Their Utility When Integrated into Density Management Decision-Support Systems 被引量:1
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作者 Peter F. Newton 《Open Journal of Forestry》 2015年第1期105-115,共11页
Based on approaches deduced from previous research findings and empirical observations from density control experiments, genetic worth effect response models were developed for black spruce (Picea mariana (Mill) BSP.)... Based on approaches deduced from previous research findings and empirical observations from density control experiments, genetic worth effect response models were developed for black spruce (Picea mariana (Mill) BSP.) and jack pine (Pinus banksiana Lamb.) plantations. The models accounted for the increased rate of stand development arising from the planting of genetically-improved stock through temporal adjustments to the species-specific site-based mean dominant height-age functions. The models utilized a relative height growth modifier based on known estimates of genetic gain. The models also incorporated a phenotypic juvenile age-mature age correlation function in order to account for the intrinsic temporal decline in the magnitude of genetic worth effects throughout the rotation. Integrating the functions into algorithmic variants of structural stand density management models produced stand development patterns that were consistent with axioms of even-aged stand dynamics. 展开更多
关键词 PICEA MARIANA Pinus banksiana Structural Stand density Management MODELS Phenotypic Juvenile Age-Mature Age Correlation Canadian BOREAL Forest Region
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Time Dimension and Ordinary Cosmic Energy Density Are Fractal Effects
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作者 Mohamed S. El Naschie 《Journal of Quantum Information Science》 2018年第2期47-51,共5页
In a short, neat and credible analysis, it is established that time is a fractal effect of the Cantor set-like topology of micro spacetime. This effect as well as the ordinary cosmic energy density of the universe is ... In a short, neat and credible analysis, it is established that time is a fractal effect of the Cantor set-like topology of micro spacetime. This effect as well as the ordinary cosmic energy density of the universe is shown to be a direct consequence of Hardy’s probability of quantum entanglement. Finally and as a general conclusion, we point out the importance of understanding the fractal origin of time as well as spacetime for resolving certain types of paradoxes arising in quantum information science. 展开更多
关键词 Random CANTOR Sets E-INFINITY EINSTEIN SPACETIME Cantorian SPACETIME Penrose Universe 'thooft Renormalon Dark ENERGY Ordinary ENERGY density Correlation Hardys Quantum Entanglement
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