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Bound State Description of Particles from a Quantum Field Theory of Fermions and Bosons, Compatible with Relativity
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作者 Hans-Peter Morsch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期562-573,共12页
Both, the dilemma to find a quantum field theory consistent with Einstein’s law of relativity and the problem to describe existing particles as bound states of matter has been solved by calculating bound state matrix... Both, the dilemma to find a quantum field theory consistent with Einstein’s law of relativity and the problem to describe existing particles as bound states of matter has been solved by calculating bound state matrix elements from a dual fermion-boson Lagrangian. In this formalism, the fermion binding energies are compensated by boson energies, indicating that particles can be generated out of the vacuum. This yields quantitative solutions for various mesons ω (0.78 GeV) - Υ (9.46 GeV) and all leptons e, μ and τ, with uncertainties in the extracted properties of less than 1‰. For transparency, a Web-page with the address htpps://h2909473.stratoserver.net has been constructed, where all calculations can be run on line and also the underlying fortran source code can be inspected. 展开更多
关键词 Quantum Field theory of Fermion and Boson Fields Hadrons and Leptons Described as Bound states of Relativistic Fermions and Bosons Leading to a Total Energy Equal to Zero
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Infinitely Many Solutions and a Ground-State Solution for Klein-Gordon Equation Coupled with Born-Infeld Theory
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作者 Fangfang Huang Qiongfen Zhang 《Journal of Applied Mathematics and Physics》 2024年第4期1441-1458,共18页
In this paper, we intend to consider a kind of nonlinear Klein-Gordon equation coupled with Born-Infeld theory. By using critical point theory and the method of Nehari manifold, we obtain two existing results of infin... In this paper, we intend to consider a kind of nonlinear Klein-Gordon equation coupled with Born-Infeld theory. By using critical point theory and the method of Nehari manifold, we obtain two existing results of infinitely many high-energy radial solutions and a ground-state solution for this kind of system, which improve and generalize some related results in the literature. 展开更多
关键词 Klein-Gordon Equation Born-Infeld theory Infinitely Many Solutions Ground-state Solution Critical Point theory
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Derivation of Martin-Hou Equation of State from Hard-particle Perturbation Theory 被引量:2
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作者 ZHANG Bing-jian (Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China) HOU Yu-chun (Department of Chemical Engineering, Zhejiang University, Hangzhou 310027, P. R. China) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第1期49-56,共8页
In this paper, the Martin-Hou equation of state is derived by using a power series representation of radial distribution function and an analytic representation of multi-section potential based on the Barker-Henderso... In this paper, the Martin-Hou equation of state is derived by using a power series representation of radial distribution function and an analytic representation of multi-section potential based on the Barker-Henderson hard-particle perturbation theory including high-order terms. In the derivation, a theoretical form of Martin-Hou equation was obtained. It had a similar form and the same capability to predict P-V-T properties as the Martin-Hou equation and no additional data were required for evaluating the constants. The characteristic constants of the theoretical expression have certain relationships with the molecular parameters. 展开更多
关键词 Perturbation theory Martin-Hou equation of state Theoretical expression P-V-T properties Molecular parameter
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Present state,basic theories,methods and progresses of investigation and assessment on marine hazardous geology in China 被引量:1
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作者 Li Peiying1, Li Ping1, Liu Lejun1, Du Jun1, Zhang Xiaolong1, Wang Shengji2 1. First Institute of Oceanography,State Oceanic Administration,Qingdao 266061,China 2. Institute of Marine Geology,Ministry of Land and Natural Resources,Qingdao 266071,China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第4期577-595,共19页
The achievement progresses of investigation and studies on marine hazardous geology are summarized and presentsd in the late 20 century in China. The importance, research value and present-day studies of marine hazard... The achievement progresses of investigation and studies on marine hazardous geology are summarized and presentsd in the late 20 century in China. The importance, research value and present-day studies of marine hazardous geology, a newly developing branch of geoscience, are well expatiated. Several often confused concepts and theories are explained and redefined here. The comment on the means of investigations, assessment of marine hazardous geology, as well as its evolution, innovation, existing questions and future tasks are also introduced and presented. The concepts of 'hazard geology', geohazard', 'map of marine hazard geology', 'integrated evaluaton on seafloor stablity' are respectively discussed, including their definition, research objects, methods and contents. The types and classification of marine hazardous geology, principles and methods of marine hazardous geology map compilation, the assessment methods and models of marine hazardous geology environment and seafloor stability and so on are also discussed. 展开更多
关键词 OCEAN hazardous geology geohazard present state of investigation and research basic theories assessment methods progresses
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Predicting of Power Quality Steady State Index Based on Chaotic Theory Using Least Squares Support Vector Machine 被引量:2
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作者 Aiqiang Pan Jian Zhou +2 位作者 Peng Zhang Shunfu Lin Jikai Tang 《Energy and Power Engineering》 2017年第4期713-724,共12页
An effective power quality prediction for regional power grid can provide valuable references and contribute to the discovering and solving of power quality problems. So a predicting model for power quality steady sta... An effective power quality prediction for regional power grid can provide valuable references and contribute to the discovering and solving of power quality problems. So a predicting model for power quality steady state index based on chaotic theory and least squares support vector machine (LSSVM) is proposed in this paper. At first, the phase space reconstruction of original power quality data is performed to form a new data space containing the attractor. The new data space is used as training samples for the LSSVM. Then in order to predict power quality steady state index accurately, the particle swarm algorithm is adopted to optimize parameters of the LSSVM model. According to the simulation results based on power quality data measured in a certain distribution network, the model applies to several indexes with higher forecasting accuracy and strong practicability. 展开更多
关键词 CHAOTIC theory Least SQUARES Support Vector Machine (LSSVM) Power Quality STEADY state Index Phase Space Reconstruction Particle SWARM Optimization
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Calculation of Viscosities of Liquid Mixtures Using Eyring's Theory in Combination with Cubic Equations of State 被引量:1
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作者 计伟荣 D.A.Lempe 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第6期770-779,共10页
Cubic equations of state (EOS) have been combined with the absolute rate theory of Eyring to calculate viscosities of liquid mixtures. A modified Huron-Vidal gE-mixing rule is employed in the calculation and in compar... Cubic equations of state (EOS) have been combined with the absolute rate theory of Eyring to calculate viscosities of liquid mixtures. A modified Huron-Vidal gE-mixing rule is employed in the calculation and in comparison with the van Laar and the Redlich-Kister-type mixing rule. The EOS method gives an accurate correlation of liquid viscosities with an overall average deviation less than 1% for 67 binary systems including aqueous solutions. It is also successful in extrapolating viscosity data over a certain temperature range using parameters obtained from the isotherm at a given temperature and in predicting viscosities of ternary solutions from binary parameters for either polar or associated systems. 展开更多
关键词 viscosity equation of state MIXING rule ABSOLUTE rate theory
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Variational Calculation of the Doubly-Excited States Nsnp of He-Like Ions via the Modified Atomic Orbitals Theory 被引量:1
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作者 Abdourahmane Diallo Ibrahima Sakho +2 位作者 Jean Kouhissoré Badiane Mamadou Diouldé Ba Modou Tine 《Journal of Modern Physics》 2021年第2期105-121,共17页
In this paper, we have declined the formalism of the method of the Modified Atomic Orbital Theory (MAOT) applied to the calculations of energies of doubly excited states 2<em>snp</em>, 3<em>snp</e... In this paper, we have declined the formalism of the method of the Modified Atomic Orbital Theory (MAOT) applied to the calculations of energies of doubly excited states 2<em>snp</em>, 3<em>snp</em>, and 4<em>snp</em> Helium-like systems. Then we also applied the variational procedure of the Modified Atomic Orbital Theory to the computations of total energies, excitation energies of doubly-excited states 2<em>snp</em>, 3<em>snp</em>, 4<em>snp</em> types of Helium-like systems. The results obtained in this work are in good agreement with the experimental and theoretical values available. 展开更多
关键词 Modified Atomic Orbital theory Doubly Excited states Excitation Energy Helium-Like Systems
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Calculation of Viscosities of Liquid Mixtures Using Eyring’s Theory in Combination with Cubic Equations of State
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作者 计伟荣 D. A. Lempe 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第6X期770-779,共10页
Cubic equations of state EOS have been combined with the absolute rate theory of Eyring to calculate viscosities of liquid mixtures. A modified Huron-Vidal gE-mixing rule is employed in the calculation and in com- par... Cubic equations of state EOS have been combined with the absolute rate theory of Eyring to calculate viscosities of liquid mixtures. A modified Huron-Vidal gE-mixing rule is employed in the calculation and in com- parison with the van Laar and the Redlich-Kister-type mixing rule. The EOS method gives an accurate correlation of liquid viscosities with an overall average deviation less than 1% for 67 binary systems including aqueous solu- tions. It is also successful in extrapolating viscosity data over a certain temperature range using parameters obtained from the isotherm at a given temperature and in predicting viscosities of ternary solutions from binary parameters for either polar or associated systems. 展开更多
关键词 VISCOSITY equation of state MIXING RULE ABSOLUTE rate theory
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Energy level analyses of even-parity J=1 and 2 Rydberg states of Sn I by multichannel quantum defect theory
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作者 由帅 凤艳艳 戴振文 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第6期2229-2237,共9页
This paper analyzes the energy levels along the even-parity J = 1 and 2 Rydberg series of Sn I by multichannel quantum defect theory. A good agreement between theoretical and experimental energy levels was achieved. B... This paper analyzes the energy levels along the even-parity J = 1 and 2 Rydberg series of Sn I by multichannel quantum defect theory. A good agreement between theoretical and experimental energy levels was achieved. Below 59198 cm^-1, a total of 85 and 23 new energy levels, respectively, in the J = 1 and J = 2 series, which cannot be measured previously by experiments, are predicted in this work. Based on the calculated admixture coefficients of each channel, interchannel interactions were discussed in detail. The results are helpful to understand the characteristics of configuration interaction among even-parity levels in Sn I. 展开更多
关键词 atom Sn Rydberg state multichannel quantum defect theory
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Valence band structure and density of states effective mass model of biaxial tensile strained silicon based on k·p theory
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作者 匡潜玮 刘红侠 +2 位作者 王树龙 秦珊珊 王志林 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期335-340,共6页
After constructing a stress and strain model, the valence bands of in-plane biaxial tensile strained Si is calculated by k·p method. In the paper we calculate the accurate anisotropy valance bands and the splitti... After constructing a stress and strain model, the valence bands of in-plane biaxial tensile strained Si is calculated by k·p method. In the paper we calculate the accurate anisotropy valance bands and the splitting energy between light and heavy hole bands. The results show that the valance bands are highly distorted, and the anisotropy is more obvious. To obtain the density of states (DOS) effective mass, which is a very important parameter for device modeling, a DOS effective mass model of biaxial tensile strained Si is constructed based on the valance band calculation. This model can be directly used in the device model of metal-oxide semiconductor field effect transistor (MOSFET). It also a provides valuable reference for biaxial tensile strained silicon MOSFET design. 展开更多
关键词 biaxial tensile strained Si k · p theory valance band density of state effective mass
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Correspondence Between GHZ States and Oriented Links in Knot Theory
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作者 QIAN Shang-Wu GU Zhi-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第10期421-423,共3页
This article generalizes our previous results for a quantum system of two nodes to a quantum system ofm(m ≥ 2) nodes. It shows that there is a one to one correspondence between 2m GHZ states for a quantum system ofm... This article generalizes our previous results for a quantum system of two nodes to a quantum system ofm(m ≥ 2) nodes. It shows that there is a one to one correspondence between 2m GHZ states for a quantum system ofm(m ≥ 2) nodes and 2m oriented links of the linkage N1 in knot theory, where N = 4 C2m = 2m(m - 1) is the numberof crossings of the link with m components, the subscript 1 denotes the order of the unoriented m components link withN crossings, i.e. the first type, actually the simplest type. 展开更多
关键词 GHZ states ORIENTED LINKS in KNOT theory inversion relations under the action of PAULI matrices
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Theory,Method and Application of a State Recognition Based on Theory of Evidence
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作者 Deling Zheng Xinbei Tang Wei Fang (Information Engineering School, University of Science and Technology Beijing, Beijing 100083, China)(Peat Marwick Huazhen CPA Firm, 100020, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第1期69-72,共4页
A new method of state recognition based on the theory of evidence was proposed. By this method, the plausible function which the sample awaiting recognition belongs to each category can be obtained through distance fu... A new method of state recognition based on the theory of evidence was proposed. By this method, the plausible function which the sample awaiting recognition belongs to each category can be obtained through distance function. For the marginal samples,two or a batch of evidences can be combined and a new plausible function can be obtained by new evidence. Then the categories of samples can be determined according to plausibility function. This method provides a beder reasoning framework. The result proves the rate of recoghition correctness. 展开更多
关键词 theory of evidence state recognition heating furnace
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Theoretical investigation on the excited state intramolecular proton transfer in Me_(2)N substituted flavonoid by the time-dependent density functional theory method
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作者 Hang Yin Ying Shi 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第5期534-538,共5页
Time-dependent density functional theory(TDDFT)method is used to investigate the details of the excited state intramolecular proton transfer(ESIPT)process and the mechanism for temperature effect on the Enol^(*)/Keto^... Time-dependent density functional theory(TDDFT)method is used to investigate the details of the excited state intramolecular proton transfer(ESIPT)process and the mechanism for temperature effect on the Enol^(*)/Keto^(*)emission ratio for the Me_(2)N-substited flavonoid(MNF)compound.The geometric structures of the S_(0) and S_(1) states are denoted as the Enol,Enol^(*),and Keto*.In addition,the absorption and fluorescence peaks are also calculated.It is noted that the calculated large Stokes shift is in good agreement with the experimental result.Furthermore,our results confirm that the ESIPT process happens upon photoexcitation,which is distinctly monitored by the formation and disappearance of the characteristic peaks of infrared(IR)spectra involved in the proton transfer and in the potential energy curves.Besides,the calculations of highest occupied molecular orbital(HOMO)and lowest unoccupied molecular orbital(LUMO)reveal that the electronegativity change of proton acceptor due to the intramolecular charge redistribution in the S_(1) state induces the ESIPT.Moreover,the thermodynamic calculation for the MNF shows that the Enol^(*)/Keto^(*)emission ratio decreasing with temperature increasing arises from the barrier lowering of ESIPT. 展开更多
关键词 time-dependent density functional theory excited state intramolecular proton transfer intramolecular charge transfer transition state
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Molecular Application of a State Specific Multi-Reference Brillouin-Wigner Perturbation Theory
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作者 H.Aksu 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第2期22-25,共4页
The single reference second order Brillouin-Wigner perturbation theory recently developed, which eliminates its size-extensivity error, has been generalized to state-specific, multi-reference (SS-MR), BWPT2 providin... The single reference second order Brillouin-Wigner perturbation theory recently developed, which eliminates its size-extensivity error, has been generalized to state-specific, multi-reference (SS-MR), BWPT2 providing a size-extensive correction to the electron correlation problem for systems that demand the use of a multi-reference function. Illustrative numerical tests of the size-extensivity corrections are made for widely used molecules in their ground states, which are pronounced multi-reference characteristics. We have implemented two-reference and three-reference cases for CH2, BH and bond breaking process in the ground states of HF molecules. The results are compared with the rigorously size-extensive methods such as the M^ller-Plesset perturbation theory, i.e., MP2, full configuration interaction (Full-CI) and allied methods using the same basis sets. 展开更多
关键词 of in Molecular Application of a state Specific Multi-Reference Brillouin-Wigner Perturbation theory FCI CCSD CISD RHF MRCI CASSCF for been MP is
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Reconstructing Equation of State for Dark Energy in Double Complex Symmetric Gravitational Theory
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作者 SHAO Ying GUI Yuan-Xing WANG Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1148-1152,共5页
We propose to study the accelerating expansion of the universe in the double complex symmetric gravitational theory (DCSGT). The universe we live in is taken as the real part of the whole spacetime MC^4(J), which ... We propose to study the accelerating expansion of the universe in the double complex symmetric gravitational theory (DCSGT). The universe we live in is taken as the real part of the whole spacetime MC^4(J), which is double complex. By introducing the spatially flat FRW metric, not only the double Friedmann equations but also the two constraint conditions py = 0 and J^2 = 1 are obtained. Farthermore, using parametric DL(z) ansatz, we reconstruct the ω/(z) and V(Ф) for dark energy from real observational data. We find that in the two cases of J = i, pJ = 0, and J = ε, pJ≠0, the corresponding equations of state ω'(z) remain close to -1 at present (z = 0) and change from below -1 to above -1. The results illustrate that the whole spacetime, i.e. the double complex spacetime MC^4(J), may be either ordinary complex (J = i, pJ = 0) or hyperbolic complex (J = ε, pJ≠ 0). And the fate of the universe would be Big Rip in the future. 展开更多
关键词 double complex symmetric gravitational theory equation of state dark energy
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Bianchi Type-V Cosmological Model with Linear Equation of State in Brans-Dicke Theory of Gravitation
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作者 Sharad Kandalkar Seema Samdurkar 《International Journal of Astronomy and Astrophysics》 2014年第3期429-436,共8页
A Bianchi type-V space time is considered with linear equation of state in the scalar tensor theory of gravitation proposed by Brans and Dicke. We use the assumption of constant deceleration parameter and power law re... A Bianchi type-V space time is considered with linear equation of state in the scalar tensor theory of gravitation proposed by Brans and Dicke. We use the assumption of constant deceleration parameter and power law relation between scalar field &oslash;and scale factor R to find the solutions. Some physical and kinematical properties of the model are also discussed. 展开更多
关键词 Bianchi Type-V Model BRANS-DICKE theory LINEAR Equation of state
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Circular Scale of Time and Energy of a Quantum State Calculated from the Schrodinger Perturbation Theory
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作者 Stanislaw Olszewski 《Journal of Modern Physics》 2014年第15期1502-1523,共22页
The main facts about the scale of time considered as a plot of a sequence of events are submitted both to a review and a more detailed calculation. Classical progressive character of the time variable, present in the ... The main facts about the scale of time considered as a plot of a sequence of events are submitted both to a review and a more detailed calculation. Classical progressive character of the time variable, present in the everyday life and in the modern science, too, is compared with a circular-like kind of advancement of time. This second kind of the time behaviour can be found suitable when a perturbation process of a quantum-mechanical system is examined. In fact the paper demonstrates that the complicated high-order Schrodinger perturbation energy of a non-degenerate quantum state becomes easy to approach of the basis of a circular scale. For example for the perturbation order N = 20 instead of 19! ≈ 1.216 × 1017 Feynman diagrams, the contribution of which should be derived and calculated, only less than 218 ≈ 2.621 × 105 terms belonging to N = 20 should be taken into account to the same purpose. 展开更多
关键词 Circular Scale of Time Schrodinger Perturbation theory Non-Degenerate Quantum state
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基于Stateflow的焊接机器人协同规划策略
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作者 李志刚 杨翔 +1 位作者 祝林 魏成法 《现代制造工程》 CSCD 北大核心 2024年第11期60-65,79,共7页
为了减少多焊接机器人协同规划过程的时间以及算力需求,提出了基于有限状态机理论的多焊接机器人协同规划方法。以汽车侧围总成为焊接对象,使用混合遗传-引力搜索算法(Genetic Algorithm-Gravitational Search Algorithm,GA-GSA)求解工... 为了减少多焊接机器人协同规划过程的时间以及算力需求,提出了基于有限状态机理论的多焊接机器人协同规划方法。以汽车侧围总成为焊接对象,使用混合遗传-引力搜索算法(Genetic Algorithm-Gravitational Search Algorithm,GA-GSA)求解工作单元中各焊接机器人焊点分配问题,完成焊接路径规划。确认焊接过程中各焊接机器人间碰撞区域,以精确建立互斥区域,使用Stateflow工具对多焊接机器人系统进行建模与仿真。根据实际工况设置系统中各焊接机器人优先级输入以及每个焊点完成焊接任务所需时间,可得该工况下系统中焊接机器人动作最优调整方案。通过2个仿真案例验证了该方法的可行性与有效性,结果表明该方法可以快速有效地完成多焊接机器人协同规划。 展开更多
关键词 多焊接机器人 有限状态机理论 侧围总成 协同规划 stateflow工具
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Rigidity Symmetry Line for Thermodynamic Fluid Equations-of-State
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作者 Leslie V. Woodcock 《Journal of Modern Physics》 2024年第5期613-633,共21页
We report progress towards a modern scientific description of thermodynamic properties of fluids following the discovery (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by perco... We report progress towards a modern scientific description of thermodynamic properties of fluids following the discovery (in 2012) of a coexisting critical density hiatus and a supercritical mesophase defined by percolation transitions. The state functions density ρ(p,T), and Gibbs energy G(p,T), of fluids, e.g. CO<sub>2</sub>, H<sub>2</sub>O and argon exhibit a symmetry characterised by the rigidity, ω = (dp/dρ)<sub>T</sub>, between gaseous and liquid states along any isotherm from critical (T<sub>c</sub>) to Boyle (T<sub>B</sub>) temperatures, on either side of the supercritical mesophase. Here, using experimental data for fluid argon, we investigate the low-density cluster physics description of an ideal dilute gas that obeys Dalton’s partial pressure law. Cluster expansions in powers of density relate to a supercritical liquid-phase rigidity symmetry (RS) line (ω = ρ<sub>rs</sub>(T) = RT) to gas phase virial coefficients. We show that it is continuous in all derivatives, linear within stable fluid phase, and relates analytically to the Boyle-work line (BW) (w = (p/ρ)<sub>T</sub> = RT), and to percolation lines of gas (PB) and liquid (PA) phases by: ρ<sub>BW</sub>(T) = 2ρ<sub>PA</sub>(T) = 3ρ<sub>PB</sub>(T) = 3ρ<sub>RS</sub>(T)/2 for T T<sub>B</sub>. These simple relationships arise, because the higher virial coefficients (b<sub>n</sub>, n ≥ 4) cancel due to clustering equilibria, or become negligible at all temperatures (0 T T<sub>B</sub>)<sub> </sub>within the gas phase. The Boyle-work line (p/ρ<sub>BW</sub>)<sub>T</sub> is related exactly at lower densities as T → T<sub>B</sub>, and accurately for liquid densities, by ρ<sub>BW</sub>(T) = −(b<sub>2</sub>/b<sub>3</sub>)<sub>T</sub>. The RS line, ω(T) = RT, defines a new liquid-density ground-state physical constant (ρ<sub>RS</sub>(0) = (2/3)ρ<sub>BW</sub>(0) for argon). Given the gas-liquid rigidity symmetry, the entire thermodynamic state functions below T<sub>B</sub> are obtainable from b<sub>2</sub>(T). A BW-line ground-state crystal density ρ<sub>BW</sub>(0) can be defined by the pair potential minimum. The Ar<sub>2</sub> pair potential, ∅ij</sub>(r<sub>ij</sub>) determines b<sub>2</sub>(T) analytically for all T. This report, therefore, advances the salient objective of liquid-state theory: an argon p(ρ,T) Equation-of-state is obtained from ∅<sub>ij</sub>(r<sub>ij</sub>) for all fluid states, without any adjustable parameters. 展开更多
关键词 Liquid-state theory Cluster Physics Percolation Lines Fluid Thermodynamics Boyle Line Rigidity-Symmetry Line
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甲烷在ZnO表面反应制合成气的微观机理研究
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作者 黄琼谊 楼波 +1 位作者 丁佳欣 王水安 《原子与分子物理学报》 CAS 北大核心 2025年第6期1-9,共9页
利用密度泛函(DFT)和过渡态理论对甲烷分子在ZnO表面的微观反应过程进行第一性原理研究,通过建立ZnO表面的吸附模型,计算了吸附能、过渡态参数和态密度,探讨了甲烷分子在氧化锌晶体表面H解离以及H_(2)和CO的生成过程,结果表明:CH_(4)在Z... 利用密度泛函(DFT)和过渡态理论对甲烷分子在ZnO表面的微观反应过程进行第一性原理研究,通过建立ZnO表面的吸附模型,计算了吸附能、过渡态参数和态密度,探讨了甲烷分子在氧化锌晶体表面H解离以及H_(2)和CO的生成过程,结果表明:CH_(4)在ZnO(010)表面的最佳吸附位点为Zn位,吸附能为-4.65 kcal/mol,甲烷在氧化锌ZnO(010)面四次解离H(反应动力学上最有利路径)所需克服的能垒分别为38.6 kcal/mol、90.8 kcal/mol、53.2 kcal/mol和35.8 kcal/mol,其中甲烷第二次解离H_(2)过程能垒最高,是反应过程的决速步,降低该基元反应的活化能是关键,而-OH的形成抑制了-CH_(3)的解离.氧空位的形成增加活性位点的数量与提高位点的活性.甲烷与氧化锌表面的反应有两次H_(2)生成反应,第一次生成H_(2)的反应难度较大. 展开更多
关键词 化学链重整 甲烷 反应机理 密度泛函理论 过渡态
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