On the transition from local equilibrium to paraequilibrium during the growth of ferrite in Fe-Mn-C austenite

1989 ◽  
Vol 37 (12) ◽  
pp. 3157-3163 ◽  
Author(s):  
Liu Zi-Kui ◽  
J. Ågren
Keyword(s):  
Local Equilibrium

scholarly journals Can Quantum Correlations Lead to Violation of the Second Law of Thermodynamics?

Entropy ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. 573
Author(s):  
Alexey V. Melkikh
Keyword(s):  
Quantum Entanglement ◽  
Local Equilibrium ◽  
Heat Engine ◽  
Thermodynamic Quantity ◽  
Second Law Of Thermodynamics ◽  
Quantum Correlations ◽  
Von Neumann Entropy ◽  
Second Law ◽  
Carnot Cycle ◽  
Technical Discussion

Quantum entanglement can cause the efficiency of a heat engine to be greater than the efficiency of the Carnot cycle. However, this does not mean a violation of the second law of thermodynamics, since there is no local equilibrium for pure quantum states, and, in the absence of local equilibrium, thermodynamics cannot be formulated correctly. Von Neumann entropy is not a thermodynamic quantity, although it can characterize the ordering of a system. In the case of the entanglement of the particles of the system with the environment, the concept of an isolated system should be refined. In any case, quantum correlations cannot lead to a violation of the second law of thermodynamics in any of its formulations. This article is devoted to a technical discussion of the expected results on the role of quantum entanglement in thermodynamics.

Geochemistry of diagenetic non-silicate minerals: kinetic considerations

1985 ◽  
Vol 315 (1531) ◽  
pp. 39-56 ◽  
Keyword(s):  
Organic Matter ◽  
Ferric Iron ◽  
Local Equilibrium ◽  
Reducing Agent ◽  
Chemical Environment ◽  
Iron Sulphide ◽  
Burial Diagenesis ◽  
Vertical Zonation ◽  
Silicate Minerals ◽  
Dissolution And Precipitation

The early stages of burial diagenesis involve the reactions of various oxidizing agents with organic matter, which is the only reducing agent buried with the sediment. In a system in which a local equilibrium is established, thermodynamic principles indicate that, inter alia , manganese, iron and sulphate should each be consumed successively to give rise to a clearly characterized vertical zonation. However, ferric iron may not react fast enough and the relative rates of reduction of Fe III and sulphate not only control the formation of iron sulphide and associated carbonate but also may lead to extreme chemical and isotopic dis-equilibrium. This produces kinetically controlled ‘micro -environments’. On a larger scale, sulphide will diffuse upward to a zone in which its oxidation leads to a reduction of pH. The various dramatic changes in chemical environment across such an interface cause both dissolution and precipitation reactions. These explain common geological observations: the occurrence of flint nodules (and their restriction to chalk hosts) and the association of phosphate with glauconite.

Wind Stress Over Waves: Effects of Sea Roughness and Atmospheric Stability

2002 ◽  
Vol 124 (3) ◽  
pp. 169-172 ◽  
Author(s):  
Dag Myrhaug ◽  
Olav H. Slaattelid
Keyword(s):  
Boundary Layer ◽  
Wind Stress ◽  
Local Equilibrium ◽  
Surface Wind ◽  
Atmospheric Stability ◽  
Sea Surface ◽  
Stability Function ◽  
Sea Surface Wind ◽  
Surface Wind Stress ◽  
Sea Surface Roughness

The paper considers the effects of sea roughness and atmospheric stability on the sea surface wind stress over waves, which are in local equilibrium with the wind, by using the logarithmic boundary layer profile including a stability function, as well as adopting some commonly used sea surface roughness formulations. The engineering relevance of the results is also discussed.

scholarly journals Evolution of Coal Permeability during Gas Injection—From Initial to Ultimate Equilibrium

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2800 ◽  
Author(s):  
Xingxing Liu ◽  
Jinchang Sheng ◽  
Jishan Liu ◽  
Yunjin Hu
Keyword(s):  
Effective Stress ◽  
Local Equilibrium ◽  
Fracture Aperture ◽  
Permeability Evolution ◽  
Full Spectrum ◽  
Coal Permeability ◽  
Fracture Pressure ◽  
Permeability Changes ◽  
Apparent Equilibrium ◽  
Non Equilibrium

The evolution of coal permeability is vitally important for the effective extraction of coal seam gas. A broad variety of permeability models have been developed under the assumption of local equilibrium, i.e., that the fracture pressure is in equilibrium with the matrix pressure. These models have so far failed to explain observations of coal permeability evolution that are available. This study explores the evolution of coal permeability as a non-equilibrium process. A displacement-based model is developed to define the evolution of permeability as a function of fracture aperture. Permeability evolution is tracked for the full spectrum of response from an initial apparent-equilibrium to an ultimate and final equilibrium. This approach is applied to explain why coal permeability changes even under a constant global effective stress, as reported in the literature. Model results clearly demonstrate that coal permeability changes even if conditions of constant effective stress are maintained for the fracture system during the non-equilibrium period, and that the duration of the transient period, from initial apparent-equilibrium to final equilibrium is primarily determined by both the fracture pressure and gas transport in the coal matrix. Based on these findings, it is concluded that the current assumption of local equilibrium in measurements of coal permeability may not be valid.

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