The thermodynamic limit and its thermodynamic stability

On the basis of the results obtained in a previous paper it is shown that in the thermodynamic limit the analogues of the Massieu-Plandc functions are linked with each other by means of the Legendre transformation. The existence of the limiting function φk(∞) implies the existence of the limiting function φl(∞) (l<k) under the same assumptions. Passage to the limit and derivation with respect to all independent variables commute. A statistical derivation of the thermodynamic stability condition in its most general form is given which leads naturally to a statistical interpretation of the concept of thermodynamic stability.

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Ability of the generalized van der Waals and Berthelot equations of state to determine the thermodynamic stability of liquid lead

Science Vision ◽

10.33493/scivis.20.04.01 ◽

2020 ◽

Vol 20 (4) ◽

pp. 132-138

Author(s):

Arumugam Ramesh ◽

Ramasamy Balasubramanian

Keyword(s):

Equation Of State ◽

Thermodynamic Limit ◽

Thermodynamic Stability ◽

Equations Of State ◽

Rapid Heating ◽

Van Der Waals ◽

Stability Boundary ◽

Reduced Form ◽

Liquid Lead ◽

Heating Up

The known van der Waals and Berthelot equations of state do-not precisely describe the thermodynamic properties of fluids. To improve its accuracy, the attractive term of the van der Waals equation of state has been modified in six different ways. These generalized equations of state have been employed to determine the spinodal (thermodynamic stability boundary) and the thermodynamic limit of superheat of liquid lead. The equations of state are rewritten in reduced form, from which follows the law of corresponding states. The appropriate modification of the attractive term of the equation of state yielding the value of thermodynamic limit of superheat agreeing with the experimental value for lead has been established. It has been established that liquid lead can be superheated, under rapid heating, up to a temperature 4565 K. That is, liquid lead can be superheated to 2544 K above the normal boiling temperature. At the thermodynamic limit of superheat, the volume of the liquid lead is 4.0095 × 10-5 m3 mol-1. This fact is to be taken into account when liquid lead is subjected to rapid heating.

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Using a Software Application to Evaluation Thermodynamic Stability on the Example of Iron

Proceedings of Universities ELECTRONICS ◽

10.24151/1561-5405-2019-24-3-309-312 ◽

2019 ◽

Vol 24 (3) ◽

pp. 309-312

Author(s):

Aleksandr S. Gulyaev ◽

◽

Vladimir B. Koltsov ◽

Elena A. Sevryukova ◽

◽

...

Keyword(s):

Thermodynamic Stability ◽

Software Application

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Theoretical and Experimental Evaluation of the Effect of Fluorinated Substituent on the Topological Landscape and Thermodynamic Stability of Zeolitic Imidazolate Framework Polymorphs

10.26434/chemrxiv.7072577.v1 ◽

2018 ◽

Author(s):

Mihails Arhangelskis ◽

Athanassis Katsenis ◽

Novendra Novendra ◽

Zamirbek Akimbekov ◽

Dayaker Gandrath ◽

...

Keyword(s):

Density Functional Theory ◽

Mechanochemical Synthesis ◽

Thermodynamic Stability ◽

Experimental Evaluation ◽

Density Functional ◽

Theoretical Calculations ◽

Zeolitic Imidazolate Framework ◽

Functional Theory ◽

Calorimetric Measurements ◽

And Calorimetry

By combining mechanochemical synthesis and calorimetry with theoretical calculations, we demonstrate that dispersion-corrected periodic density functional theory (DFT) can accurately survey the topological landscape and predict relative energies of polymorphs for a previously inaccessible fluorine-substituted zeolitic imidazolate framework (ZIF). Experimental screening confirmed two out of three theoretically anticipated polymorphs, and the calorimetric measurements provided an excellent match to theoretically calculated energetic difference between them.

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Thermodynamic Stability of Hexagonal and Rhombohedral Bn at Cvd Conditions from Van der Waals Corrected First Principles Calculations

10.26434/chemrxiv.8052218.v3 ◽

2019 ◽

Author(s):

Henrik Pedersen ◽

Björn Alling ◽

Hans Högberg ◽

Annop Ektarawong

Keyword(s):

Thin Films ◽

Thermodynamic Stability ◽

First Principles ◽

Thermal Equilibrium ◽

Density Functional ◽

Van Der Waals ◽

Chemical Vapor ◽

First Principles Calculations ◽

Functional Theory ◽

The Stability

Thin films of boron nitride (BN), particularly the sp2-hybridized polytypes hexagonal BN (h-BN) and rhombohedral BN (r-BN) are interesting for several electronic applications given band gaps in the UV. They are typically deposited close to thermal equilibrium by chemical vapor deposition (CVD) at temperatures and pressures in the regions 1400-1800 K and 1000-10000 Pa, respectively. In this letter, we use van der Waals corrected density functional theory and thermodynamic stability calculations to determine the stability of r-BN and compare it to that of h-BN as well as to cubic BN and wurtzitic BN. We find that r-BN is the stable sp2-hybridized phase at CVD conditions, while h-BN is metastable. Thus, our calculations suggest that thin films of h-BN must be deposited far from thermal equilibrium.

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Faculty Opinions recommendation of Correlation of RNA secondary structure statistics with thermodynamic stability and applications to folding.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1163637.625403 ◽

2009 ◽

Author(s):

Nathan Baker

Keyword(s):

Secondary Structure ◽

Thermodynamic Stability ◽

Rna Secondary Structure

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Nε-Acetyl L-α Lysine Improves Activity and Stability of α-Amylase at Acidic Conditions: A Comparative Study with other Osmolytes

Protein and Peptide Letters ◽

10.2174/0929866526666191105130041 ◽

2020 ◽

Vol 27 (6) ◽

pp. 551-556

Author(s):

Nidhya N. Joghee ◽

Gurunathan Jayaraman ◽

Masilamani Selladurai

Keyword(s):

Enzyme Activity ◽

Amino Acid ◽

Thermodynamic Stability ◽

Protective Effects ◽

Residual Enzyme Activity ◽

Functional Stability ◽

Biotechnological Applications ◽

Optimal Temperature ◽

Acidic Conditions ◽

Cellular Components

Background: Nε-acetyl L-α lysine is an unusual acetylated di-amino acid synthesized and accumulated by certain halophiles under osmotic stress. Osmolytes are generally known to protect proteins and other cellular components under various stress conditions. Objective: The structural and functional stability imparted by Nε-acetyl L-lysine on proteins were unknown and hence was studied and compared to other commonly known bacterial osmolytes - ectoine, proline, glycine betaine, trehalose and sucrose. Methods: Effects of osmolytes on the temperature and pH profiles, pH stability and thermodynamic stability of the model enzyme, α-amylase were analyzed. Results: At physiological pH, all the osmolytes under study increased the optimal temperature for enzyme activity and improved the thermodynamic stability of the enzyme. At acidic conditions (pH 3.0), Nε-acetyl L-α lysine and ectoine improved both the catalytic and thermodynamic stability of the enzyme; it was reflected in the increase in residual enzyme activity after incubation of the enzyme at pH 3.0 for 15 min by 60% and 63.5% and the midpoint temperature of unfolding transition by 11°C and 10°C respectively. Conclusion: Such significant protective effects on both activity and stability of α-amylase imparted by addition of Nε-acetyl L-α lysine and ectoine at acidic conditions make these osmolytes interesting candidates for biotechnological applications.

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