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Signe Kjelstrup - One of the best experts on this subject based on the ideXlab platform.
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Expanded Focus on Non-Equilibrium Thermodynamics
International Journal of Thermophysics, 2013Co-Authors: Signe Kjelstrup, William M. HaynesAbstract:The field of non-Equilibrium Thermodynamics is currently a subject of increasing interest. Several books on new developments and applications have appeared, providing a general thermodynamic basis for a multitude of rate processes. The classical theory has been recently extended to deal with transport through phase boundaries and to non-Equilibrium quantum systems. Optimization of entropy production is important in chemical and mechanical engineering. Several lines of research are addressing the non-linear regime. These generalizations give hope for more consistent thermodynamic modeling in the future, for yet a wider range of applications. The International Journal of Thermophysics, with a tradition for reports on high quality experimental, computational, and theoretical results in thermophysics, has therefore found it timely to accept responsibility for assisting in the development of this branch of thermophysics. By naming a new Associate Editor with special responsibility for non-Equilibrium Thermodynamics, we hope to give the field more attention. Our hope is that a synergy can be realized between our traditional target group of authors and a new group of authors who are experienced in developing and using non-Equilibrium Thermodynamics to explain, understand, and describe processes with several driving forces. As a first move to foster such a development, this issue is publishing a collection of six articles, based on invited talks presented at the 6th International Workshop of
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Mesoscopic non-Equilibrium Thermodynamics.
2013Co-Authors: Dick Bedeaux, Signe KjelstrupAbstract:Classical Thermodynamics is a theory for a collection of molecules in Equilibrium. What happens if the number of molecules in the system becomes smaller and smaller, and the system boundaries reflect conditions further and further away from Equilibrium? Can we still use Thermodynamics? In our work we have found that the answer is yes. The field of non-Equilibrium Thermodynamics can be extended to mesoscopic systems and describe in a systematic manner even molecular behavior far from Equilibrium conditions. Using the concept of internal variables along the reaction coordinate we derive the law of mass action. This shows that the mesoscopic analysis gives a natural explanation of the fact that the reaction rate is a nonlinear function of the Gibbs energy of the reaction. The theory can be applied to RNA stretching experiments. This application shows why stretching RNA leads to different results when one uses a constant force to stretch or when one stretches to a constant length. This relates to the fact that for small systems the results differ for different ensembles. Important work was done on this issue by Hill who wrote a book in the sixties of the last century on Equilibrium Thermodynamics of small systems. Furthermore the mesoscopic analysis can be applied to active transport by the Ca-ATPase. We were able to explain how temperature differences feature in this phenomenon. This understanding is relevant for instance to understand thermogenesis. In conclusion we find that mesoscopic non-Equilibrium thermodynamic theory can be used, also on a molecular level.
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Mesoscopic non-Equilibrium Thermodynamics of non-isothermal reaction-diffusion
Physical chemistry chemical physics : PCCP, 2010Co-Authors: Dick Bedeaux, Ignacio Pagonabarraga, J. M. Ortiz De Zárate, Jan V. Sengers, Signe KjelstrupAbstract:We show how the law of mass action can be derived from a thermodynamic basis, in the presence of temperature gradients, chemical potential gradients and hydrodynamic flow. The solution gives the law of mass action for the forward and the reverse contributions to the net chemical reaction. In addition we derive the fluctuation–dissipation theorem for the fluctuating contributions to the reaction rate, heat flux and mass fluxes. All these results arise without any other assumptions than those which are common in mesoscopic non-Equilibrium Thermodynamics; namely quasi-stationary transport across a high activation energy barrier, and local Equilibrium along the reaction coordinate. Arrhenius-type behaviour of the kinetic coefficients is recovered. The thermal conductivity, Soret coefficient and diffusivity are significantly influenced by the presence of a chemical reaction. We thus demonstrate how chemical reactions can be fully reconciled with non-Equilibrium Thermodynamics.
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Chapter 14:Applied Non-Equilibrium Thermodynamics
Applied Thermodynamics of Fluids, 2010Co-Authors: Signe Kjelstrup, Dick BedeauxAbstract:Non-Equilibrium Thermodynamics describes all kinds of transport processes. This chapter must focus on a few, namely transport of heat and mass in homogeneous and heterogeneous systems, in the absence or presence of chemical reactions. This introduction gives a brief history of the field, a list of g...
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Mesoscopic Non‐Equilibrium Thermodynamics and Biological Systems
AIP Conference Proceedings, 2008Co-Authors: Signe KjelstrupAbstract:de Groot and Mazur [1] explained how classical non‐Equilibrium Thermodynamics can be extended to deal with internal variables; i.e. variables that are not controlled externally. The extension, called mesocopic non‐Equilibrium Thermodynamics, can capture the non‐linear nature of activated transport processes, and can also describe the coupling among mass and heat flows and chemical reactions. I show what it means for active ion transport by the Ca2+‐ATPase in sarcoplasmic reticulum, and discuss the premises of the method.
Dick Bedeaux - One of the best experts on this subject based on the ideXlab platform.
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Mesoscopic non-Equilibrium Thermodynamics.
2013Co-Authors: Dick Bedeaux, Signe KjelstrupAbstract:Classical Thermodynamics is a theory for a collection of molecules in Equilibrium. What happens if the number of molecules in the system becomes smaller and smaller, and the system boundaries reflect conditions further and further away from Equilibrium? Can we still use Thermodynamics? In our work we have found that the answer is yes. The field of non-Equilibrium Thermodynamics can be extended to mesoscopic systems and describe in a systematic manner even molecular behavior far from Equilibrium conditions. Using the concept of internal variables along the reaction coordinate we derive the law of mass action. This shows that the mesoscopic analysis gives a natural explanation of the fact that the reaction rate is a nonlinear function of the Gibbs energy of the reaction. The theory can be applied to RNA stretching experiments. This application shows why stretching RNA leads to different results when one uses a constant force to stretch or when one stretches to a constant length. This relates to the fact that for small systems the results differ for different ensembles. Important work was done on this issue by Hill who wrote a book in the sixties of the last century on Equilibrium Thermodynamics of small systems. Furthermore the mesoscopic analysis can be applied to active transport by the Ca-ATPase. We were able to explain how temperature differences feature in this phenomenon. This understanding is relevant for instance to understand thermogenesis. In conclusion we find that mesoscopic non-Equilibrium thermodynamic theory can be used, also on a molecular level.
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Mesoscopic non-Equilibrium Thermodynamics of non-isothermal reaction-diffusion
Physical chemistry chemical physics : PCCP, 2010Co-Authors: Dick Bedeaux, Ignacio Pagonabarraga, J. M. Ortiz De Zárate, Jan V. Sengers, Signe KjelstrupAbstract:We show how the law of mass action can be derived from a thermodynamic basis, in the presence of temperature gradients, chemical potential gradients and hydrodynamic flow. The solution gives the law of mass action for the forward and the reverse contributions to the net chemical reaction. In addition we derive the fluctuation–dissipation theorem for the fluctuating contributions to the reaction rate, heat flux and mass fluxes. All these results arise without any other assumptions than those which are common in mesoscopic non-Equilibrium Thermodynamics; namely quasi-stationary transport across a high activation energy barrier, and local Equilibrium along the reaction coordinate. Arrhenius-type behaviour of the kinetic coefficients is recovered. The thermal conductivity, Soret coefficient and diffusivity are significantly influenced by the presence of a chemical reaction. We thus demonstrate how chemical reactions can be fully reconciled with non-Equilibrium Thermodynamics.
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Chapter 14:Applied Non-Equilibrium Thermodynamics
Applied Thermodynamics of Fluids, 2010Co-Authors: Signe Kjelstrup, Dick BedeauxAbstract:Non-Equilibrium Thermodynamics describes all kinds of transport processes. This chapter must focus on a few, namely transport of heat and mass in homogeneous and heterogeneous systems, in the absence or presence of chemical reactions. This introduction gives a brief history of the field, a list of g...
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Mesoscopic non-Equilibrium Thermodynamics for quantum systems
Physica A-statistical Mechanics and Its Applications, 2001Co-Authors: Dick Bedeaux, P. MazurAbstract:Abstract An extension of the scheme of non-Equilibrium Thermodynamics developed previously is given for quantum mechanical systems. A master equation for the density matrix of the system follows from this scheme. Onsager relations are given and derived. Application to a spin system gives the Bloch equations. The application to a one-dimensional damped harmonic oscillator results in equations, which enable us to calculate the usual Green functions. For the last case we derive, as a new alternative, quantum mechanical Langevin equations. A new element, compared to the classical Langevin equations, is a random velocity. The correlation of the random velocity with the random force then results from the zero point motion of the oscillator. The application of mesoscopic non-Equilibrium Thermodynamics to these wellknown problems illustrates the usefullness of this method.
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Chapter 4:Local Equilibrium in Non-Equilibrium Thermodynamics
Experimental Thermodynamics Volume X, 1Co-Authors: Signe Kjelstrup, Dick BedeauxAbstract:The hypothesis of local Equilibrium is central in non-Equilibrium Thermodynamics. We define and review support for this hypothesis for three-, two- and one-dimensional, macroscopic thermodynamic systems. The hypothesis can also be supported in mesoscopic systems. It does not apply to density-gradient theories as these introduce nonlocal variables, but is found to apply if we define surface excess variables according to Gibbs. The hypothesis can therefore be actively used to predict surface properties.
Subenoy Chakraborty - One of the best experts on this subject based on the ideXlab platform.
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Emergent Scenario in first and second order non-Equilibrium Thermodynamics and stability analysis
Annals of Physics, 2017Co-Authors: Sourav Haldar, Pritikana Bhandari, Subenoy ChakrabortyAbstract:Abstract First and second order non-Equilibrium Thermodynamics are studied in the context of particle creation mechanism for homogeneous and isotropic FLRW model and a general formulation of the emergent scenario is investigated. Finally, the stability of the non-Equilibrium Thermodynamics is examined.
Tim Holland - One of the best experts on this subject based on the ideXlab platform.
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Using Equilibrium Thermodynamics to Understand Metamorphism and Metamorphic Rocks
Elements, 2010Co-Authors: Roger Powell, Tim HollandAbstract:Metamorphic rocks, formed at elevated temperature and pressure from pre-existing rocks inside mountain belts, provide a seemingly unpromising target for the application of Equilibrium Thermodynamics. This is because metamorphic rocks develop their mineral assemblages along a pressure-temperature (P-T) path, with pressure and temperature continuously changing along the path. However, in a successful model for the formation of such rocks, involving the essential role of fluid or melt, the mineral assemblages observed at the Earth's surface can be considered to reflect a state of frozen-in Equilibrium as the rocks are exhumed towards the Earth's surface. Equilibrium Thermodynamics applied to such mineral assemblages allow P-T information to be extracted. Currently the best way to do this is via calculated phase diagrams, the most powerful being P-T pseudosections. These diagrams portray the variation of mineral assemblages with P-T for a specified rock composition. Pseudosections allow the P-T conditions of the frozen-in Equilibrium to be estimated, and can also give information on the P-T path followed. Such paths are an essential input in constraining the processes involved in mountain-building and the evolution of continental crust.
J. Miguel Rubi - One of the best experts on this subject based on the ideXlab platform.
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Mesoscopic non-Equilibrium Thermodynamics
Contributions to science, 2016Co-Authors: J. Miguel RubiAbstract:Autonomous microsystems, such as biomolecules, molecular motors, nanomotors, and active particles, are functionally dependent on nanoscale energy conversion mechanisms. The non-Equilibrium processes taking place in those systems are strongly influenced by the presence of fluctuations. Contributions to the free energy that vanish in the infinite particle number limit cannot be neglected and may exert an important influence in the dynamics of the system. We show that, in spite of these features, non-Equilibrium Thermodynamics applies. A rigorous theoretical foundation that accounts for the statistical nature of mesoscale systems over short time scales, “mesoscopic non-Equilibrium Thermodynamics”, is currently being developed and offers a promising framework for interpreting future experiments in chemistry and biochemistry. [Contrib Sci 11(2): 147-151 (2015)]
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Mesoscopic Non-Equilibrium Thermodynamics: Application to Radiative Heat Exchange in Nanostructures
Thermodynamics, 2011Co-Authors: Agustín Pérez-madrid, J. Miguel Rubi, Luciano C. LapasAbstract:Systems in conditions of Equilibrium strictly follow the rules of Thermodynamics (Callen, 1985). In such cases, despite the intricate behaviour of large numbers of molecules, the system can be completely characterized by a few variables that describe global average properties. The extension of Thermodynamics to non-Equilibrium situations entails the revision of basic concepts such as entropy and its related thermodynamic potentials as well as temperature that are strictly defined in Equilibrium. Non-Equilibrium Thermodynamics proposes such an extension (de Groot & Mazur, 1984) for systems that are in local Equilibrium. Despite its generality, this theory is applicable only to situations in which the system manifests a deterministic behaviour where fluctuations play no role. Moreover, nonEquilibrium Thermodynamics is formulated in the linear response domain in which the fluxes of the conserved local quantities (mass, energy, momentum, etc.) are proportional to the thermodynamic forces (gradients of density, temperature, velocity, etc.). While the linear approximation is valid for many transport processes, such as heat conduction and mass diffusion, even in the presence of large gradients, it is not appropriate for activated processes such as chemical and biochemical reactions in which the system immediately enters the non-linear domain or for small systems in which fluctuations may be relevant. To circumvent these limitations, one has to perform a probabilistic description of the system, which in turn has to be compatible with thermodynamic principles. We have recently proposed such a description aimed at obtaining a simple and comprehensive explanation of the dynamics of non-Equilibrium systems at the mesoscopic scale. The theory, mesoscopic non-Equilibrium Thermodynamics, has provided a deeper understanding of the concept of local Equilibrium and a framework, reminiscent of non-Equilibrium Thermodynamics, through which fluctuations in non-linear systems can be studied. The probabilistic interpretation of the density together with conservation laws in phase-space and positiveness of global entropy changes set the basis of a theory similar to non-Equilibrium Thermodynamics but of a much broader range of applicability. In particular, the fact of its being based on probabilities instead of densities allows for the consideration of mesoscopic systems and their fluctuations. The situations that can be studied with this formalism
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Non-Equilibrium Thermodynamics of small-scale systems
Energy, 2007Co-Authors: J. Miguel RubiAbstract:Small thermodynamic systems exhibit peculiar behavior different from that observed in long-scale systems. Non-Equilibrium processes taking place in those systems are strongly influenced by the presence of fluctuations which can be large. Contributions to the free energy which vanish at the infinite number of particles limit cannot be neglected and may exert an important influence on the dynamics. We show that in spite of these important differences, the method of non-Equilibrium Thermodynamics still applies when reducing the size of the system. By using this method, assumption of local Equilibrium at the mesoscale thereby leads to the formulation of a mesoscopic non-Equilibrium Thermodynamics from which expressions for the non-Equilibrium currents and kinetic equations for the probability density can be obtained.
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The non-Equilibrium Thermodynamics approach to the dynamics of mesoscopic systems
Journal of Non-Equilibrium Thermodynamics, 2004Co-Authors: J. Miguel RubiAbstract:We show that the method of non-Equilibrium Thermodynamics can be applied to describe the behaviour of systems defined at the meso-scale whose dynamics is mediated by the presence of fluctuations. The mesoscopic non-Equilibrium Thermodynamics approach we propose yields the kinetic equations for the evolution of the probability density governing the dynamics. We present applications to different mesoscopic systems undergoing linear and nonlinear transport and activated processes.
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Inertial effects in non-Equilibrium Thermodynamics
Physica A: Statistical Mechanics and its Applications, 1999Co-Authors: J. Miguel Rubi, Agustín Pérez-madridAbstract:Abstract We discuss inertial effects in systems outside Equilibrium within the framework of non-Equilibrium Thermodynamics. By introducing a Gibbs equation in which the entropy depends on the probability density, we are able to describe a system of Brownian particles immersed in a heat bath in both inertial and diffusion regimes. In the former, a relaxation equation for the diffusion current is obtained whereas in the latter we recover Fick's law. Our approach, which uses the elements of the theory of internal degrees of freedom, constitutes the mesoscopic version of a previous analysis which takes into account the kinetic energy of diffusion.