Non-equilibrium reaction rates in chemical kinetic equations

2018 ◽  
Author(s):  
Yuriy Gorbachev
Keyword(s):  
Kinetic Equations ◽  
Reaction Rates ◽  
Chemical Kinetic ◽  
Equilibrium Reaction ◽  
Non Equilibrium

DSMC Predictions of Non-equilibrium Reaction Rates

2011 ◽  
Author(s):  
R. B. Bond ◽  
M. A. Gallis ◽  
J. R. Torczynski
Keyword(s):  
Reaction Rates ◽  
Equilibrium Reaction ◽  
Non Equilibrium

Thermodynamics and foundations of mass-action kinetics

2005 ◽  
Vol 30 (1-2) ◽  
pp. 3-113 ◽  
Author(s):  
Miloslav Pekař
Keyword(s):  
Chemical Kinetics ◽  
Reaction Rate ◽  
Chemical Potential ◽  
Kinetic Equations ◽  
Reaction Rates ◽  
Equilibrium States ◽  
Mass Action ◽  
Rate Equations ◽  
Mass Action Kinetics ◽  
Non Equilibrium

A critical overview is given of phenomenological thermodynamic approaches to reaction rate equations of the type based on the law of mass-action. The review covers treatments based on classical equilibrium and irreversible (linear) thermodynamics, extended irreversible, rational and continuum thermodynamics. Special attention is devoted to affinity, the applications of activities in chemical kinetics and the importance of chemical potential. The review shows that chemical kinetics survives as the touchstone of these various thermody-namic theories. The traditional mass-action law is neither demonstrated nor proved and very often is only introduced post hoc into the framework of a particular thermodynamic theory, except for the case of rational thermodynamics. Most published “thermodynamic'’ kinetic equations are too complicated to find application in practical kinetics and have merely theoretical value. Solely rational thermodynamics can provide, in the specific case of a fluid reacting mixture, tractable rate equations which directly propose a possible reaction mechanism consistent with mass conservation and thermodynamics. It further shows that affinity alone cannot determine the reaction rate and should be supplemented by a quantity provisionally called constitutive affinity. Future research should focus on reaction rates in non-isotropic or non-homogeneous mixtures, the applicability of traditional (equilibrium) expressions relating chemical potential to activity in non-equilibrium states, and on using activities and activity coefficients determined under equilibrium in non-equilibrium states.

scholarly journals The Dissipative Photochemical Origin of Life: UVC Abiogenesis of Adenine

2021 ◽  
Author(s):  
Karo Michaelian
Keyword(s):  
Origin Of Life ◽  
Kinetic Equations ◽  
Reaction Rates ◽  
Photon Flux ◽  
Common Precursor ◽  
Wavelength Absorption ◽  
The Common ◽  
The Origin Of Life ◽  
Precursor Molecules ◽  
Non Equilibrium

I describe the non-equilibrium thermodynamics and the photochemical mechanisms which may have been involved in the dissipative synthesis, proliferation, and evolution of the fundamental molecules at the origin of life from simpler and more common precursor molecules such as HCN, H2O and CO2 under the impressed UVC photon flux of the Archean. The fundamental molecules absorb strongly in this UVC region and exhibit strong coupling between their electronic excited and ground states which endows them with efficient photon disipative capacity (broad wavelength absorption and rapid radiationless dexcitation) suggestive of dissipative structuring. The autocatalytic nature of the synthesized molecules in dissipating the same photochemical potential that directed their synthesis leads to their proliferation. The non-linearity in the photochemical and chemical reaction rates provides numerous stationary states which can be reached by amplification of a molecular concentration fluctuation near a bifurcation, promoting the system into states of generally higher photon disspative efficacy. An example is given of the UV photochemical dissipative structuring, proliferation, and evolution of molecules on route to the nucleobase adenine from the common precursor molecules HCN and H2O occurring within a fatty acid vesicle. The kinetic equations are resolved under different environmental conditions, providing a non-equilibrium thermodynamic analysis of the appearance of an early important molecule for the origin of life.

A nonnegativity preserved efficient algorithm for atmospheric chemical kinetic equations

2015 ◽  
Vol 271 ◽  
pp. 519-531 ◽  
Author(s):  
Fan Feng ◽  
Zifa Wang ◽  
Jie Li ◽  
Gregory R. Carmichael
Keyword(s):  
Efficient Algorithm ◽  
Kinetic Equations ◽  
Chemical Kinetic
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