期刊文献+
共找到1,405篇文章
< 1 2 71 >
每页显示 20 50 100
Thermodynamics in a quantum corrected Reissner-Nordstr?m-AdS black hole and its GUP-corrections
1
作者 宋建君 刘成周 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期345-353,共9页
We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and ... We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and the remnant state,respectively,and discuss their consistency.Then,we investigate the quantum tunneling from the event horizon of massless scalar particle by using the null geodesic method,and charged massive boson W^(±)and fermions by using the Hamilton-Jacob method.It is shown that the same Hawking temperature can be obtained from these tunneling processes of different particles and methods.Next,by using the generalized uncertainty principle(GUP),we study the quantum corrections to the tunneling and the temperature.Then the logarithmic correction to the black hole entropy is obtained. 展开更多
关键词 black hole thermodynamics quantum corrections quantum tunneling generalized uncertainty principle
原文传递
Dialectical Thermodynamics’Solution to the Conceptual Imbroglio That Is the Reversible Path
2
作者 José C. Íñiguez 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期775-799,共25页
According to the second law of thermodynamics, as currently understood, any given transit of a system along the reversible path proceeds with a total entropy change equal to zero. The fact that this condition is also ... According to the second law of thermodynamics, as currently understood, any given transit of a system along the reversible path proceeds with a total entropy change equal to zero. The fact that this condition is also the identifier of thermodynamic equilibrium, makes each and every point along the reversible path a state of equilibrium, and the reversible path, as expressed by a noted thermodynamic author, “a dense succession of equilibrium states”. The difficulties with these notions are plural. The fact, for example, that systems need to be forced out of equilibrium via the expenditure of work, would make any spontaneous reversible process a consumer of work, this in opposition to common thermodynamic wisdom that makes spontaneous reversible processes the most efficient transformers of work-producing-potential into actual work. The solution to this and other related impasses is provided by Dialectical Thermodynamics via its previously proved notion assigning a negative entropy change to the energy upgrading process represented by the transformation of heat into work. The said solution is here exemplified with the ideal-gas phase isomerization of butane into isobutane. 展开更多
关键词 Thermodynamic Reversibility Solution to Inconsistencies Dialectical thermodynamics
下载PDF
Confirmation of the First Law of Thermodynamics in Theory and Extended Bernoulli Equation
3
作者 Chengshu Jin 《Journal of Applied Mathematics and Physics》 2023年第2期409-420,共12页
The internal energy change of ideal gas does not depend on the volume and pressure. The internal energy change of real gas has not any relation with the volume and pressure, which had been proved. If the internal ener... The internal energy change of ideal gas does not depend on the volume and pressure. The internal energy change of real gas has not any relation with the volume and pressure, which had been proved. If the internal energy change had not any relation with the volume and pressure, we could confirm the first law of thermodynamics in theory. Simultaneously, the internal energy change is the state function that shall be able to be proved in theory. If the internal energy change depended on the volume and pressure, we could not prove that the internal energy change is the state function and the chemical thermodynamics theory is right. The extended or modified Bernoulli equation can be derived from the energy conservation law, and the internal energy change, heat, and friction are all considered in the derivation procedure. The extended Bernoulli equation could be applied to the flying aircraft and mechanical motion on the gravitational field, for instance, the rocket and airplane and so on. This paper also revises some wrong ideas, viewpoints, or concepts about the thermodynamics theory and Bernoulli equation. 展开更多
关键词 First Law of thermodynamics Chemical thermodynamics Bernoulli Equation Static Pressure Head FRICTION
下载PDF
Removal of Organochlorine from Model Oil Using Mg-Modified ZSM-5 Zeolite:Dechlorination Performance,Regeneration,and Thermodynamics 被引量:1
4
作者 Cheng Xingyuan Gu Jie +4 位作者 Huang Bingtian Bing Liancheng Han Dezhi Wang Guangjian Wang Fang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第2期24-32,共9页
Various metal-modified ZSM-5 zeolite adsorbents prepared by the impregnation method were applied to the removal of organic chlorides from model naphtha.The adsorption performance and regeneration stability were invest... Various metal-modified ZSM-5 zeolite adsorbents prepared by the impregnation method were applied to the removal of organic chlorides from model naphtha.The adsorption performance and regeneration stability were investigated by static adsorption experiments.The morphologies,structural features,and physicochemical properties of the adsorbents were characterized by X-ray diffraction,Brunauer-Emmett-Teller analysis,NH3 temperature-programmed desorption,scanning electron microscopy,transmission electron microscopy,and pyridine adsorption infrared spectroscopy.The Mg/ZSM-5 zeolite adsorbent possessed a relatively high specific surface area and good metal dispersion and exhibited the best dechlorination and regeneration performance.The characterization results revealed that introduction of the metal exerted a significant influence on the acidic properties of the catalyst surface.A decrease in the ratio of Brønsted acidic sites to Lewis acidic sites and an increase in the amount of moderately acidic sites were confirmed to be responsible for the excellent adsorption performance of the Mg-modified ZSM-5 zeolite.Furthermore,the Langmuir adsorption isotherm model was applied to study the adsorption equilibrium and thermodynamics of the Mg/ZSM-5 adsorbent under mild conditions.The results revealed that the removal of 1,2-dichloroethane by the Mg/ZSM-5 adsorbent was endothermic,spontaneous,disordered,and primarily involved physical adsorption. 展开更多
关键词 adsorption dechlorination ZSM-5 zeolite metal modification thermodynamics
下载PDF
Pseudo-rapidity distributions of charged particles in asymmetric collisions using Tsallis thermodynamics
5
作者 Jun‑Qi Tao Hong‑Bin He +4 位作者 Hua Zheng Wen‑Chao Zhang Xing‑Quan Liu Li‑Lin Zhu Aldo Bonasera 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期120-127,共8页
The pseudo-rapidity distributions of the charged particles produced in the asymmetric collision systems p+Al,p+Au and ^(3)He+Au at√S_(NN)=200 GeV GeV are evaluated in the framework of a fireball model with Tsallis th... The pseudo-rapidity distributions of the charged particles produced in the asymmetric collision systems p+Al,p+Au and ^(3)He+Au at√S_(NN)=200 GeV GeV are evaluated in the framework of a fireball model with Tsallis thermodynamics.The fireball model assumes that the experimentally measured particles are produced by fireballs following the Tsallis distribution and it can effectively describe the experimental data.Our results as well as previous results for d+Au collisions at√S_(NN)=200 GeV GeV and p+Pb collisions at√S_(NN)=5.02 TeV TeV validate that the fireball model based on Tsallis thermodynamics can provide a universal framework for pseudo-rapidity distribution of the charged particles produced in asymmetric collision systems.We predict the centrality dependence of the total charged particle multiplicity in the p+Al,p+Au and 3He+Au collisions.Additionally,the dependences of the fireball model parameters(y_(0a),y_(0A),σ_(a) and σ_(A))on the centrality and system size are studied. 展开更多
关键词 Tsallis thermodynamics Fireball model Pseudo-rapidity distribution Heavy-ion collisions Charged particles
下载PDF
Li^(+)-ion bound crown ether functionalization enables dual promotion of dynamics and thermodynamics for ambient ammonia synthesis
6
作者 Qiyang Cheng Sisi Liu +8 位作者 Mengfan Wang Lifang Zhang Yanzheng He Jiajie Ni Jingru Zhang Chengwei Deng Yi Sun Tao Qian Chenglin Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期191-197,I0007,共8页
Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous ... Electrosynthesis of ammonia from the reduction of nitrogen is still confronted with the limited supply of gas reactant in dynamics as well as high activation barrier in thermodynamics.Unfortunately,despite tremendous efforts devoted to electrocatalysts themselves,they still fail to tackle the above two challenges simultaneously.Herein,we employ a heterogeneous catalyst adlayer-composed of crown ethers associated with Li^(+)ions-to achieve the dual promotion of dynamics and thermodynamics for ambient ammonia synthesis.Dynamically,the bound Li^(+)ions interact with the strong quadrupole moment of nitrogen,and trigger considerable reactant flux toward the catalyst.Thermodynamically,Li^(+)associated with the oxygen of crown ether achieves a higher density of states at the Fermi level for the catalyst,enabling effortless electron transfer from the catalysts to nitrogen and thus greatly reducing the activation barrier.As expected,the proof-of-concept system achieves an ammonia yield rate of 168.5μg h^(-1)mg^(-1)and a Faradaic efficiency of 75.3%at-0.3 V vs.RHE.This system-level approach opens up pathways for tackling the two key challenges that have limited the field of ammonia synthesis. 展开更多
关键词 Li^(+)-ion bound crown ether DYNAMICS thermodynamics Nitrogen reduction Ammonia synthesis
下载PDF
Shadow thermodynamics of AdS black hole with the nonlinear electrodynamics term
7
作者 郑何斌 牟平辉 +1 位作者 陈芸仙 李国平 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第8期201-208,共8页
We creatively employ the shadow radius to study the thermodynamics of a charged Ad S black hole with a nonlinear electrodynamics(NLED)term.First,the connection between the shadow radius and event horizon is constructe... We creatively employ the shadow radius to study the thermodynamics of a charged Ad S black hole with a nonlinear electrodynamics(NLED)term.First,the connection between the shadow radius and event horizon is constructed with the aid of the geodesic analysis.It turns out that the black hole shadow radius shows a positive correlation as a function of the event horizon radius.Then in the shadow context,we find that the black hole temperature and heat capacity can be presented by the shadow radius.Further analysis shows that the shadow radius can work similarly to the event horizon in revealing black hole phase transition process.In this sense,we construct the thermal profile of the charged Ad S black hole with inclusion of the NLED effect.In the P<Pc case,it is found that the N-type trend of the temperature given by the shadow radius is always consistent with that obtained by using the event horizon.Thus,we can conclude for the charged Ad S black hole that the phase transition process can be intuitively presented as the thermal profile in the shadow context.Finally,the effects of NLED are carefully analyzed. 展开更多
关键词 AdS black hole the nonlinear electrodynamics shadow thermodynamics
原文传递
Thermodynamics and Microphysical Characteristics of an Extreme Rainfall Event Under the Influence of a Low-level Jet over the South China Coast
8
作者 徐碧裕 黎慧琦 +7 位作者 叶朗明 刘显通 饶晓娜 肖辉 徐加民 林青 蒲义良 黄青兰 《Journal of Tropical Meteorology》 SCIE 2023年第2期216-235,共20页
In this paper,the data of Automatic Weather Stations(AWSs),ERA5 reanalysis,sounding,wind profile radar,and dual-polarization radar are used to study an extreme rainfall event in the south China Coast on 11 to 12 May 2... In this paper,the data of Automatic Weather Stations(AWSs),ERA5 reanalysis,sounding,wind profile radar,and dual-polarization radar are used to study an extreme rainfall event in the south China Coast on 11 to 12 May 2022 from the aspects of thermodynamics and microphysical characteristics under the influence of low-level jets(LLJs).Results show that:(1)The extreme rainfall event can be divided into two stages:the first stage(S1)from 0000 to 0600 LST on May 12 and the second stage(S2)from 0700 to 1700 LST on the same day.During S1,the rainfall is mainly caused by the upper-level shortwave trough and the boundary layer jet(BLJ),characterized by strong upward motion on the windward side of mountains.In S2,the combined influence of the BLJ and synoptic-system-related low-level jet(SLLJ)increases the vertical wind shear and vertical vorticity,strengthening the rainstorm.In combination with the effect of topography,a warm and humid southwest flow continuously transports water vapor to farther north,resulting in a significant increase in rainfall over the study area(on the terrain’s windward slope).From S1 to S2,the altitude of a divergence center in the upper air decreases obviously.(2)The rainfalls in the two stages are both associated with the mesoscale convergence line(MCL)on the surface,and the wind field from the mesoscale outflow boundary(MOB)in S1 is in the same direction as the environmental winds.Due to a small area of convergence that is left behind the MOB,convection moves eastward quickly and causes a short duration of heavy rainfall.In S2,the convergence along the MOB is enhanced,which strengthens the rainfall and leads to strong outflows,further enhancing the surface convergence near the MOB and forming a positive feedback mechanism.It results in a slow motion of convection and a long duration of heavy rainfall.(3)In terms of microphysics,the center of a strong echo in S1 is higher than in S2.The warm-rain process of the oceanic type characterizes both stages,but the convective intensity in S2 is significantly stronger than that in S1,featuring bigger drop sizes and lower concentrations.It is mainly due to the strengthening of LLJs,which makes small cloud droplets lift to melting levels,enhancing the ice phase process(riming process),producing large amounts of graupel particles and enhancing the melting and collision processes as they fall,resulting in the increase of liquid water content(LWC)and the formation of large raindrops near the surface. 展开更多
关键词 low-level jet thermodynamics MICROPHYSICS heavy rain south China coast
下载PDF
Thermodynamics of warm axionic Abelian gauge inflation
9
作者 李喜彬 武燕玲 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期671-680,共10页
Inflationary spectral index from the Langevin equation is calculated under the frame of warm inflationary scenario with inflaton interacting with U(1) gauge fields through the Chern–Simons coupling ∝ФF_(μv)F^(μv)... Inflationary spectral index from the Langevin equation is calculated under the frame of warm inflationary scenario with inflaton interacting with U(1) gauge fields through the Chern–Simons coupling ∝ФF_(μv)F^(μv). Under the strong dissipative condition, the spectral index is calculated in terms of the ratio of Hubble parameter to temperature H/T. Then relation between H/T and other cosmic parameters is analytically expressed, based on which a spectral index related to the Chern–Simons coupling strength is further obtained. Numerical results show that cosmic temperature T closes to a constant during inflation and decreases after inflation without a reheating process. Meanwhile, the ratio H/T tends to a constant if the gauged coupling constant is less than a threshold. This phenomenon shows that cosmic temperature may be an important physical parameter with a special value and adiabatic approximation still holds. We obtain the estimate H/T ≤ 0.3377 during inflation from Planck data and other constraint conditions. 展开更多
关键词 axion inflation thermodynamics
原文传递
A Computational Study of Microhydrated N-Acetyl-Phenylalaninylamide (NAPA): Kinetics and Thermodynamics
10
作者 Mohammad Alauddin Mohammad Masud Parvez Mohammad Abdul Matin 《Computational Molecular Bioscience》 2023年第4期63-74,共12页
The formations of [NAPA-A(H<sub>2</sub>O)<sub>n</sub> (n = 1, 2, 3, 4)] complexes have been studied employing DFT/wB97XD/cc-pVTZ computational level to understand the kinetics and thermodynamic... The formations of [NAPA-A(H<sub>2</sub>O)<sub>n</sub> (n = 1, 2, 3, 4)] complexes have been studied employing DFT/wB97XD/cc-pVTZ computational level to understand the kinetics and thermodynamics for the hydration reactions of N-acetyl-phenylalaninylamide (NAPA). Thermodynamic parameters such as reaction energy (E), enthalpy (H), Gibb’s free energy (G), specific heat capacity (C<sub>v</sub>), entropy (S), and change of these parameters (ΔE<sub>r</sub>, ΔH<sub>r</sub>, ΔGr, ΔC<sub>r</sub>, and ΔS<sub>r</sub>) were studied using the explicit solvent model. The predicted values of H, G, C, and S increase with the sequential addition of water in NAPA-A due to the increase in the total number of vibrational modes. On the other hand, the value of ΔE<sub>r</sub>, ΔH<sub>r</sub>, and ΔG<sub>r</sub> increases (more negative to less negative) gradually for n = 1, 2, 3, and 4 that indicates an increase of hydration in NAPA-A makes exothermic to endothermic reactions. The barrier heights for the transition states (TS) of [NAPA-A(H<sub>2</sub>O)<sub>n</sub> (n = 1, 2, 3, 4)] complexes are predicted to lie at 4.41, 4.05, 3.72 and 2.26 kcal/mol respectively below the reactants. According to the calculations, the formations of [NAPA-A(H<sub>2</sub>O)<sub>1</sub>] and [NAPA-A(H<sub>2</sub>O)<sub>2</sub>] complexes are barrierless reactions because both water molecules are strongly bonded via two hydrogen bonds in the backbone of NAPA-A. On the contrary, the reactions of [NAPA-A(H<sub>2</sub>O)<sub>3</sub>] and [NAPA-A(H<sub>2</sub>O)<sub>4</sub>] complexation are endothermic and the barrier heights are predicted to stay at 6.30 and 10.54 kcal/mol respectively above the reactants. The free energy of activation (Δ<sup>‡</sup>G<sup>0</sup>) for the reaction of [NAPA-A(H<sub>2</sub>O)<sub>1</sub>], [NAPA-A(H<sub>2</sub>O)<sub>2</sub>], [NAPA-A(H<sub>2</sub>O)<sub>3</sub>], and [NAPA-A(H<sub>2</sub>O)<sub>4</sub>] complexation are 4.43, 4.28, 3.83 and 5.11 kcal/mol respectively which are very low. As well as the rates of reactions are 3.490 × 10<sup>9</sup> s<sup>-1</sup>, 4.514 × 10<sup>9</sup> s<sup>-1</sup>, 9.688 × 10<sup>9</sup> s<sup>-1</sup>, and 1.108 × 10<sup>9</sup> s<sup>-1</sup> respectively which are very fast and spontaneous. 展开更多
关键词 Microhydration DFT Transition States KINETICS thermodynamics
下载PDF
A Review of Recent Trends in Quantum Thermodynamics and a System’s Behavioural Analysis of the Universe Originating as a Quantum Energy System
11
作者 Stephen J. Palmer 《Journal of Modern Physics》 CAS 2023年第1期60-71,共12页
This paper combines a review of recent advances in quantum thermodynamics, including work on objective collapse (Zurek’s quantum Darwinism) and quantum gravity (Verlinde’s quantum gravity explanation), with a redefi... This paper combines a review of recent advances in quantum thermodynamics, including work on objective collapse (Zurek’s quantum Darwinism) and quantum gravity (Verlinde’s quantum gravity explanation), with a redefinition of entropy generation as systems’ change process. These concepts are used as systems’ behaviour analysis tools to allow us to revisit Hartle and Hawking’s 1983 quantum universe and develop a hypothesis for how physically a universe starting in a quantum state could evolve into our current universe, based on systems analysis. The outcome of this analysis raises a question: do we already have the elements of a “theory of everything” hiding in plain sight within recent advances in quantum thermodynamics? 展开更多
关键词 Exergy Entropy Quantum thermodynamics Systems Behavioural Analysis Quantum Universe
下载PDF
Quantum Gravity Based on Generalized Thermodynamics
12
作者 Sergei Yurievich Eremenko 《Journal of Applied Mathematics and Physics》 2023年第4期988-1028,共41页
This paper proposes a novel approach and simplified model of Quantum Gravity based on the unification framework of Generalized Thermodynamics which suggests cross-related terms and modified equations of General Relati... This paper proposes a novel approach and simplified model of Quantum Gravity based on the unification framework of Generalized Thermodynamics which suggests cross-related terms and modified equations of General Relativity and Quantum Mechanics. To address the “background problem”, a metric tensor is introduced into stationary Schrödinger equations via curved coordinates yielding quantum spacetime variation term. Then quantum Lagrangian is added to Einstein-Hilbert functional yielding quantum stress-energy tensor. Obtained from one variational principle, two theories are linked by a common quantum spacetime field. The theory offers some interpretations of the quantum vacuum spacetime fluctuations, zero-point-fields, quantum fields shifting towards high spacetime densities, the quantum nature of spacetime, and black hole singularity. 展开更多
关键词 Quantum Gravity General Relativity Quantum Spacetime Generalized thermodynamics Unified Theory
下载PDF
Black Holes and the Third Law of Thermodynamics Revisited
13
作者 Miguel Socolovsky 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第2期499-505,共7页
Black holes contradict the Nernst-Planck (N/P) version of the 3rd law of thermodynamics, but agree with its unattainability (U) version. This happens without contradiction, because the N/P and U versions are not equiv... Black holes contradict the Nernst-Planck (N/P) version of the 3rd law of thermodynamics, but agree with its unattainability (U) version. This happens without contradiction, because the N/P and U versions are not equivalent, namely, N/P implies U but U does not imply N/P. So, black holes obey the weaker version of the 3rd law, but not the stronger one. 展开更多
关键词 thermodynamics Third Law Black Holes
下载PDF
Crystallization thermodynamics of 2,4(5)-dinitroimidazole in binary solvents 被引量:1
14
作者 Pengbao Lian Lizhen Chen +3 位作者 Dan He Guangyuan Zhang Zishuai Xu Jianlong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期173-182,共10页
2,4(5)-Dinitroimidazole(2,4(5)-DNI)is an important organic intermediate,and itself can also be used for energetic material.In this work,the solubility of 2,4(5)-DNI in(methanol+water,acetonitrile+water,acetone+water)b... 2,4(5)-Dinitroimidazole(2,4(5)-DNI)is an important organic intermediate,and itself can also be used for energetic material.In this work,the solubility of 2,4(5)-DNI in(methanol+water,acetonitrile+water,acetone+water)binary solvents were measured by using a dynamic test method from 278.15 K to 323.15 K under 101.1 k Pa.The Jouyban–Acree model,van't Hoff–Jouyban–Acree model,Apelblat–Jouyb an–Acree model,Ma model,and Sun model were used to correlate the experimental data.The values of relative average deviation(RAD)and root-mean-square deviation(RMSD)were very small,indicating that the error between the experimental value and the correlated value was very small.The thermodynamic parameters such as dissolution enthalpy,dissolution entropy and Gibbs energy were calculated based on solubility data.High-purity of 2,4(5)-DNI was efficiently obtained by using cooling and dilution crystallization method. 展开更多
关键词 2 4(5)-Dinitroimidazole Solid-liquid equilibrium Solubility model Three thermodynamic parameters Cooling and dilution crystallization
下载PDF
Motoyosi Sugita—A “Widely Unknown” Japanese Thermodynamicist Who Explored the 4th Law of Thermodynamics for Creation of the Theory of Life
15
作者 Kazumoto Iguchi 《Open Journal of Biophysics》 2016年第4期125-232,共109页
The purpose of this paper is to introduce to you, the Western people, nowadays a “widely unknown” Japanese thermodynamicist by the name of Motoyosi Sugita and his study on the thermodynamics of transient phenomena a... The purpose of this paper is to introduce to you, the Western people, nowadays a “widely unknown” Japanese thermodynamicist by the name of Motoyosi Sugita and his study on the thermodynamics of transient phenomena and his theory of life. This is because although he was one of the top theoretical physicists in Japan before, during and after WWII and after WWII he promoted the establishment of the biophysical society of Japan as one of the founding members, he himself and his studies themselves have seemed to be totally forgotten nowadays in spite that his study was absolutely important for the study of life. Therefore, in this paper I would like to present what kind of person he was and what he studied in physics as a review on the physics work of Motoyosi Sugita for the first time. I will follow his past studies to introduce his ideas in theoretical physics as well as in biophysics as follows: He proposed the bright ideas such as the quasi-static change in the broad sense, the virtual heat, and the field of chemical potential etc. in order to establish his own theory of thermodynamics of transient phenomena, as the generalization of the Onsager-Prigogine’s theory of the irreversible processes. By the concept of the field of chemical potential that acquired the nonlinear transport, he was seemingly successful to exceed and go beyond the scope of Onsager and Prigogine. Once he established his thermodynamics, he explored the existence of the 4th law of thermodynamics for the foundation of theory of life. He applied it to broad categories of transient phenomena including life and life being such as the theory of metabolism. He regarded the 4th law of thermodynamics as the maximum principle in transient phenomena. He tried to prove it all life long. Since I have recently found that his maximum principle can be included in more general maximum principle, which was known as the Pontryagin’s maximum principle in the theory of optimal control, I would like to explain such theories produced by Motoyosi Sugita as detailed as possible. And also I have put short history of Motoyosi Sugita’s personal life in order for you to know him well. I hope that this article helps you to know this wonderful man and understand what he did in the past, which was totally forgotten in the world and even in Japan. 展开更多
关键词 Unknown Japanese Thermodynamicist Motoyosi Sugita thermodynamics of Transient Phenomena Virtual Heat Broad Quasi-Static Change Chemical Potential Field of Chemical Potential Diffusion Phenomena Number of Partition Dissipation Function Onsager’s Theory of Irreversible Processes Prigogine’s Least Production of Entropy 4th Law of thermodynamics Maximum Principle Pontryagin’s Maximum Principle Bellman’s Optimality Principle Theory of Metabolism Theory of Life CYBERNETICS
下载PDF
Some Ideas of James Watt in Contemporary Energy Conversion Thermodynamics
16
作者 Jovan Mitrovic 《Journal of Modern Physics》 2022年第4期385-409,共25页
James Watt contributed significantly to the development of the thermodynamics of energy conversion as a science. Several of his ideas are now integral part of thermodynamics, but Watt as their creator is not mentioned... James Watt contributed significantly to the development of the thermodynamics of energy conversion as a science. Several of his ideas are now integral part of thermodynamics, but Watt as their creator is not mentioned. This paper presents some of Watt’s concepts of energy conversion, including his thermodynamic analysis of the Newcomen steam engine that marks the beginning of thermal engineering. The analysis illuminated the causes of the enormously high heat losses in the installation and showed the ways for their reduction. This led him to a new conception of the steam engine with a separate condenser. Not less important was Watt’s determination of some physical properties of water and steam used as the working substance. In the experiments he observed the decrease of the latent heat of steam with increasing temperature and its disappearance at very high temperature led him to postulate the existence of a thermodynamic critical state of water. He introduced the work associated with volume change into thermodynamics and illustrated it graphically. Several of Watt’s numerous ideas deserve to be included into the history of the thermodynamics of energy conversion but they are rarely mentioned in the scientific literature. Arguably the most important is the First Law of Thermodynamics, which he introduced in his 1769 patent and related works in 1774 and 1778. 展开更多
关键词 thermodynamics Energy Conservation and Conversation Mechanical Equivalent of Heat James Watt Volume Work First Principle of thermodynamics Latent Heat Steam Expansion and Condensation
下载PDF
On Clausius’, Post-Clausius’, and Negentropic Thermodynamics
17
作者 José C. Íñiguez 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第4期1425-1458,共34页
The evidence here provided shows that the thermodynamics of the second law, as currently understood, originated in a correction of the flaws affecting Clausius original work on this matter. The body of knowledge emerg... The evidence here provided shows that the thermodynamics of the second law, as currently understood, originated in a correction of the flaws affecting Clausius original work on this matter. The body of knowledge emerging from this correction has been here called post-Clausius’ thermodynamics. The said corrections, carried on with the intended goal of preserving the validity of Clausius’ main result, namely the law of increasing entropy, made use of a number of counterintuitive or logically at fault notions. A joint revision of Clausius’ and post-Clausius’ work on the second law, carried on retaining some of Clausius original notions, and disregarding others introduced by post-Clausius thermodynamics, led this author to results in direct contradiction to the law of increasing entropy. Among the key results coming out of this work we find the one stating that the total-entropy change for spontaneous thermodynamic processes is the result of the summation of the opposite-sign contributions coming from the entropic (energy degrading) and negentropic (energy upgrading) changes subsumed by any such process. These results also show, via the total-entropy change for a non-reversible heat engine, that negentropic thermodynamics subsumes post-Clausius thermodynamics as a special case. 展开更多
关键词 Clausius’ Entropy Law in Contradiction with Its Premises Post-Clausius’ thermodynamics Emerges from the Biased Correction of the Flaws in Clausius Entropy Law Negentropic thermodynamics and the Transformation of Heat into Work as a Negentropic Process
下载PDF
Formation and thermodynamics of CaS-bearing inclusions during Ca treatment in oil casting steels 被引量:7
18
作者 Xue-feng Bai Yan-hui Sun +2 位作者 Rui-mei Chen Yi-min Zhang Yi-fan Cai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第5期573-587,共15页
Industrial experiments were carried out to investigate the formation of CaS-bearing inclusion during Ca double modification in oil casting steels using polished cross sections and electrolytic extraction. Immediately ... Industrial experiments were carried out to investigate the formation of CaS-bearing inclusion during Ca double modification in oil casting steels using polished cross sections and electrolytic extraction. Immediately after Ca addition, the role of newly generated CaS as an intermediate reaction product, which modified the Al_2O_3 inclusion into a liquid calcium aluminate, was confirmed. The formation of transient CaS was attributed to the high surface segregation of S at the liquid steel-calcium vapor interface, where a simple site coverage model based upon the Langmuir adsorption equation was established. Moreover, a CaS outer layer surrounding the liquid calcium aluminate was attained mainly in the tundish, which was distributed unevenly on the surface of liquid particles according to the three-dimensional mapping results. The surface of a well-modified calcium aluminate with higher CaO activity and Al_2O_3 activity under bulk composition conditions in the tundish acted as a favorable site for the generation of CaS. Additionally, CaS could be precipitated directly onto existing inclusions during solidification of the steel, which led to various morphologies of CaS-bearing inclusions in slabs. Furthermore, the phase transformation of inclusions during solidification was strongly influenced both by the S content and the Ca/S ratio in the tundish via thermodynamics. 展开更多
关键词 CAS INCLUSIONS CA TREATMENT electrolytic extraction thermodynamics three-dimensional investigations
下载PDF
Thermodynamics and kinetics of hydriding and dehydriding reactions in Mg-based hydrogen storage materials 被引量:11
19
作者 Qian Li Yangfan Lu +10 位作者 Qun Luo Xiaohua Yang Yan Yang Jun Tan Zhihua Dong Jie Dang Jianbo Li Yuan Chen Bin Jiang Shuhui Sun Fusheng Pan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2021年第6期1922-1941,共20页
Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity,environmental benignity,and high Clarke number characteristics.However,the limited thermodynamic... Mg-based materials are one of the most promising hydrogen storage candidates due to their high hydrogen storage capacity,environmental benignity,and high Clarke number characteristics.However,the limited thermodynamics and kinetic properties pose major challenges for their engineering applications.Herein,we review the recent progress in improving their thermodynamics and kinetics,with an emphasis on the models and the influence of various parameters in the calculated models.Subsequently,the impact of alloying,composite,and nanocrystallization on both thermodynamics and dynamics are discussed in detail.In particular,the correlation between various modification strategies and the hydrogen capacity,dehydrogenation enthalpy and temperature,hydriding/dehydriding rates are summarized.In addition,the mechanism of hydrogen storage processes of Mg-based materials is discussed from the aspect of classical kinetic theories and microscope hydrogen transferring behavior.This review concludes with an outlook on the remaining challenge issues and prospects. 展开更多
关键词 Magnesium-based hydrogen storage materials Hydriding/dehydriding reactions thermodynamics Kinetic models Analysis methods
下载PDF
Thermodynamics at microscales: 3D→2D, 1D and 0D 被引量:8
20
作者 Kun Dong Feng Huo Suojiang Zhang 《Green Energy & Environment》 SCIE CSCD 2020年第3期251-258,共8页
Today, the laws of traditional thermodynamics are facing challenges when science is growing rapidly toward the microscale-world, even quantum hypothesis. In this work, the thermodynamics of nano-confinement and quantu... Today, the laws of traditional thermodynamics are facing challenges when science is growing rapidly toward the microscale-world, even quantum hypothesis. In this work, the thermodynamics of nano-confinement and quantum thermodynamics are summarized to illustrate their developments at the microscales. 展开更多
关键词 thermodynamics CONFINEMENT Quantum scale ENTROPY Reduced dimension
下载PDF
上一页 1 2 71 下一页 到第
使用帮助 返回顶部