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Generalized Van der Waals Equation for Liquid-Vapor Equilibria in a Stationary gravitational field

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World Journal of Condensed Matter Physics 2021年第1期11卷 1-11页

作者： Makokiyu Godlove Akumbom Georges Collince Fouokeng Martin Tchoffo Lukong Cornelius Fai Unité de Recherche de Matiere Condensée d’Electronique et de Traitement de Signal (URMACETS) Department of Physics Faculty of Science University of Dschang Dschang Cameroon Centre d’Etudes et de Recherche en Agronomie et en Biodiversité Faculté d’Agronomie et des Sciences Agricoles (FASA) Université de Dschang Dschang Cameroon

The behavior of liquids undergoing phase transition in the gravitational field is studied by considering the generalized Van der Waals equation. Considering the two simple models for liquid-vapor boundary of a pure classical fluid, the generalized Van der Waals equation shows how the three critical parameters (critical temperature, critical volume and critical pressure), suffice to describe the reduced state parameters (reduced temperature, reduced volume and reduced pressure), the concentration profile and the liquid-vapor boundary position, which can be used to observe transition phenomenon. This model shows how the form of the equation can influence the vertical phase separation induced by the stationary gravitational field, and on the gas condensation effects.

关键词： Liquid-Vapor Phase Transition gravitational field Classical Fluid Concentration Profile

Impact of gravitation on gaseous pollutant source identification

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Chinese Journal of Aeronautics 2013年第2期26卷 261-268页

作者： Pang Liping Zhang Yu Qu Hongquan Hu Tao Zhao Jingquan School of Aviation Science and Engineering Beihang University College of Information Engineering North China University of Technology

It is necessary to identify a gaseous pollutant source rapidly so that prompt actions can be taken, but this is one of the difficulties in the inverse problem areas. In this paper, an approach to identifying a sudden continuous emission pollutant source based on single sensor information is developed to locate a source in an enclosed space with a steady velocity field. Because the gravity has a very important influence on the gaseous pollutant transport and the source identification, its influence is analyzed theoretically and a conclusion is drawn that the velocity of fluid is a key factor to effectively help weaken the gravitational influence. Further studies for a given 2-D case by using the computational fluid dynamics （CFD） method show that when the velocity of inlet is less than one certain value, the influence of gravity on the pollutant transport is very significant, which will change the velocity field obviously. In order to quantitatively judge the practical applicability of identification approach, a synergy degree of the velocity fields before and after a source appearing is proposed as a condition for considering the influence of gravity. An experimental device simulating pollutant transmission was set up and some experiments were conducted to verify the practical application of the above studies in the actual gravitational environment. The results show that the proposed approach can successfully locate the sudden constant source when the experimental situations meet the identified conditions.

关键词： Experiment Gaseous pollutant source identification gravitational field Location probability Synergy degree of velocity fields Ventilated enclosed space

Quantum entropies of electromagnetic and gravitational fields on Taub-NUT black hole background

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Journal of Chongqing University 2005年第4期4卷 243-246页

作者：刘晓莹 Department of Physics Zhanjiang Normal collegeZhanjiang 524048 P.R. China

The main characteristics and Petrov type of Taub-NUT spacetime are studied, and the quantum entropy of Taub-NUT black hole due to electromagnetic and gravitational fields is calculated via brick-wall model. It is shown that the quantum entropy has both the linearly and the logarithmically divergent terms. For electromagnetic field, these terms depend on the characteristic of the black hole; while for gravitational field, they depend not only on the characteristic of the black hole but also on the spin of the fields.

关键词： Taub-NUT black hole electromagnetic field gravitational field quantum entropy

Experimental Ferrogravitational field around Untwisting Closed Superconductor

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Journal of Modern Physics 2020年第11期11卷 1807-1826页

作者： Robert A. Sizov Individual Researcher Moscow Russia

The study by the author of magnetic scattering neutrons in the structures of ferrimagnets, as well as his experiments with the separation of magnetic charges in dipole pairs ±g in magnetic field, showed that fundamental magnetic particles (magnetic charges) are real structural components of atoms and substance. It is the magnetic poles, and not the moving electric charges are the direct sources of all magnetic fields and magnetic manifestations in Nature. Basic reasons of ignoring the magnetic fundamental particles by world physical theory, for almost 150 years, are the ultra-harsh confinement of these particles in substance which radically is different from the confinement electrons, as well as the vicious concept of the electric magnetism Maxwell. Rotating magnetic dipoles in conductors which are untwisted by electric current, are direct sources of the vortex magnetic field rotH. One should also expect the formation of a vortex electric field rotE forming by rotating electric dipoles which are untwisted by the current of magnetic charges. This article provides an experimental answer to the question: what field is formed around a conductor if joint direct currents of electric Je and magnetic Jg charges are passed through it? The author’s experiments have shown that in this case the vortex electromagnetic current is realized which manifests itself as the vortex electromagnetic (gravitational) field. It is possible to implement such a process, according to the results of the author’s research, exclusively in superconductors. The vector character of the gravitational field is in many respects similar to the vortex magnetic field which makes it possible to introduce such it states as paragravitation and ferrogravitation into representations. To create joint currents of electric and magnetic charges, the autho

关键词： Magnetic Charges Magnetons Antimagnetons Magnetic Dipoles True Antielectrons S-Gravitons gravitational field Ferro- and Paragravitation gravitational “Dark Energy” gravitational Levitation

Gravitation induced shrinkage of Mercury's orbit

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Chinese Physics B 2020年第10期29卷 598-600页

作者： Moxian Qian Xibin Li Yongjun Cao College of physics and electronic infoimation Inner Mongolia Normal UniversityHohhot 010022China

In general relativity, Mercury's orbit becomes approximately elliptical and the its perihelion has thus an additional advance. We demonstrate, meanwhile, that in comparison of those given by Newton's theory of gravitation for the orbit of the Mercury, the circumference and the area are reduced by 40.39 km and 2.35 × 10^9 km^2, respectively, besides the major-axis contraction pointed out recently, and all are produced by the curved space within Einstein's theory of gravitation. Since the resolution power of present astronomical distance measurement technology reaches one kilometer, the shrinkage of Mercury's orbit can then be observable.

关键词： Mercury's orbit gravitational field general relativity

Neutrino oscillation interference phase in Kerr space time

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Chinese Physics B 2009年第12期18卷 5575-5582页

作者：任军贾孟文袁常青 School of Science Hebei University of Technology

The mass neutrino interference phases along the null trajectory and the geodesic line in Kerr space-time are studied on the plane θ = π/2. Because of the rotation object in Kerr space-time, a particle travelling along the radial geodesic must have a dragging effect produced by the angular momentum of the central object. We give the correction of the phase due to the rotation of the space-time. We find that the type-I interference phase along the geodesic remains the double of that along the null on the condition that the rotating quantity parameter a^2 is preserved and the higher order terms are negligible （e.g. a^4）. In addition, we calculate the proper oscillation length in Kerr space-time. All of our results can return to those in Schwarzschild space-time as the rotating parameter a approaches zero.

关键词： gravitational field general relativity neutrino interference phase Kerr space-time geodesic line

Behaviour of granular matter under gravity-induced stress gradient:A two-dimensional numerical investigation

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International Journal of Mining Science and Technology 2021年第3期31卷 439-450页

作者： Ruilin Li Guoqing Zhou Pin-Qiang Mo Matthew R.Hall Jun Chen Daqing Chen Shangyue Cai State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China GeoEnergy Research Centre Faculty of EngineeringUniversity of NottinghamNottingham NG72RDUK School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China

Gravity is the most important load source in mining and geotechnical engineering,which causes both the stress level and stress gradient inside *** from the stress level,the influence of gravity-induced stress gradient on the behaviour of the material is still *** in-deep study on it will help to promote the understanding of material behaviour,especially for those cases related to unconventional gravity such as terrestrial ng physical modelling and extraterrestrial resource exploitation(g is the terrestrial gravitational acceleration).In this study,a high-order homogenization for granular materials is proposed at first,in which the stress gradient is drawn into the constitutive representation by adopting a representative volume element(RVE).The consolidation and shear strength behaviour of RVE are then investigated by performing numerical biaxial *** results show that all the compressibility,shear strength,shear stiffness,volumetric deformation,and critical state behaviour show a stress gradient dependence.A coupling between stress gradient,stress level,and material properties is also *** observations suggest that,besides the stress level,extra attention needs to be paid to material responses related to stress gradient during engineering practices.

关键词： Stress gradient Representative volume element Granular matter gravitational field Discrete element method

Photonic zitterbewegung and its interpretation

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Chinese Physics B 2012年第2期21卷 76-80页

作者： Wang Zhi-Yong Xiong Cai-Dong Qiu Qi Liao-Yun School of Optoelectronic Information University of Electronic Science and Technology of ChinaChengdu 610054China

In terms of the volume-integrated Poynting vector, we present a quantum field-theory investigation of the zitterbewegung （ZB） of photons, and show that this ZB occurs only in the presence of virtual longitudinal and scalar photons. To present a heuristic explanation for such a ZB, by assuming that the space time is sufficiently close to the flat Minkowski space, we show that the gravitational interaction can result in the ZB of photons.

关键词： zitterbewegung photons gravitational field

Schwarzschild-de-Sitter Solution in Quantum Gauge Theory of Gravity

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Communications in Theoretical Physics 2007年第5期47卷 843-846页

作者： Gheorghe Zet Camelia Popa Doina Partenie Department of Physics ＂Gh. Asachi＂ Technical University Iasi 700050 Romania Faculty of Physics ＂A1. I. Cuza＂ University Iasi 700506 Romania

We use the theory based on the gravitational gauge group G to obtain a spherical symmetric solution of the field equations for the gravitational potentials on a Minkowski space-time. The gauge group G is defined and then we introduce the gauge-covariant derivative Dμ. The strength tensor of the gravitational gauge field is also obtained and a gauge-invariant Lagrangian including the cosmological constant is constructed. A model whose gravitational gauge potentials A^α μ （x） have spherical symmetry, depending only on the radial coordinate τ is considered and an analytical solution of these equations, which induces the Schwarzschild-de-Sitter metric on the gauge group space, is then determined. All the calculations have been performed by GR Tensor II computer algebra package, running on the Maple V platform, along with several routines that we have written for our model.

关键词： gauge theory gravitational field spherical symmetry