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In defense of thermodynamics

Comment on “Concepts against mathematics: self-inconsistency in thermodynamic evaluations”

Journal of Thermal Analysis and Calorimetry
Author: Robert H. Swendsen

Introduction In a recent publication, Drebushchak [ 1 ] has made the startling claim that “Thermodynamics is not a rigorous mathematical science.” He also stated that for a specific thermodynamic expression, “two different

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AlPO 4 · 2H 2 O [ 9 ] AlPO 4 · H 2 O-H1-4 [ 8 ] and AlPO 4 -21 [ 2 ] and Al 1− x Fe x PO 4 ( x = 0) [ 4 ] precursors. By reason, the mechanism, thermodynamics and kinetics of solid-state reactions are needed in order to take advantage of this

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-state reaction at room temperature and to study the kinetics and thermodynamics of the decomposition of NH 4 NiPO 4 ·6H 2 O using TG-DTA technique. Non-isothermal kinetics of the decomposition process of NH 4 NiPO 4 ·6H 2 O was interpreted by Flynm

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Abstract  

A new high-nitrogen complex [Cu(Hbta)2]·4H2O (H2bta = N,N-bis-(1(2)H-tetrazol-5-yl) amine) was synthesized and characterized by elemental analysis, single crystal X-ray diffraction and thermogravimetric analyses. X-ray structural analyses revealed that the crystal was monoclinic, space group P2(1)/c with lattice parameters a = 14.695(3) Å, b = 6.975(2) Å, c = 18.807(3) Å, β = 126.603(1)°, Z = 4, D c = 1.888 g cm−3, and F(000) = 892. The complex exhibits a 3D supermolecular structure which is built up from 1D zigzag chains. The enthalpy change of the reaction of formation for the complex was determined by an RD496–III microcalorimeter at 25 °C with the value of −47.905 ± 0.021 kJ mol−1. In addition, the thermodynamics of the reaction of formation of the complex was investigated and the fundamental parameters k, E, n,
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Updelta S_{ \ne }^{{{\uptheta}}}$$ \end{document}
,
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Updelta H_{ \ne }^{{{\uptheta}}}$$ \end{document}
, and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Updelta G_{ \ne }^{{{\uptheta}}}$$ \end{document}
were obtained. The effects of the complex on the thermal decomposition behaviors of the main component of solid propellant (HMX and RDX) indicated that the complex possessed good performance for HMX and RDX.
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Abstract  

An investigation on the thermodynamics of complex formation between Ag(I) ion and two tripodal ligands tris[(2-pyridyl)methyl]amine (TPA) and 6,6′-bis-[bis-(2-pyridylmethyl)aminomethyl]-2,2′-bipyridine (BTPA) has been carried out in the aprotic solvents dimethylsulfoxide (DMSO) and dimethylformamide (DMF) by means of potentiometry and titration calorimetry. The results for TPA are compared with those already obtained for other aliphatic tripodal polyamines. In general, the TPA ligand forms complexes less stable than 2,2′,2″-triaminotriethylamine (TREN) and tris(2-(methylamino)ethyl)amine (Me3TREN) as a result of the combination of higher structural rigidity of TPA and lower σ-donor ability of pyridinic moieties with respect to primary and secondary amines. The same trend is found if the stability of Ag(I) complex with TPA is compared with that of tris(2-(dimethylamino)ethyl)amine (ME6TREN), despite the pyridinic nitrogen is formally a tertiary one. Theoretical calculations run to explain the reasons of this weaker interaction indicate that this difference is due to solvation, rather than to steric or σ-donor effects. The ligand BTPA is able to form bimetallic species whose relative stability is largely influenced by the different solvation of Ag(I) ion in DMSO and DMF rather than by the difference in the dielectric constants of these two media.

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of the system research, the aim of this study was to prepare single phase α-LiZnPO 4 ·H 2 O via the above method with LiH 2 PO 4 ·H 2 O, ZnSO 4 ·7H 2 O, and Na 2 CO 3 and to study the kinetics and thermodynamics of the decomposition of α-LiZnPO 4 ·H

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Abstract  

The influence of H2O–EtOH and H2O–Acetone mixed solvents at various compositions on the thermodynamics of complex formation reaction between crown ether 18-crown-6 (18C6) and glycine (Gly) was studied. The standard thermodynamic parameters of the complex [Gly18C6] (log K°, Δr H°, Δr S°) were calculated from thermochemical data at 298.15 K obtained by titration calorimetry. The complex stability and its formation enthalpy increase with increasing the non aqueous component concentration in both mixed solvents. The thermodynamic data were discussed on the basis of the solvation thermodynamic approach and the solvation contributions of the reagents and of the complex to the complex stability were analyzed.

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Abstract  

Calorimetry, densimetry, 1H NMR and UV–vis spectroscopy were used to characterize inclusion complex formation of hydroxypropylated α- and β-cyclodextrins with meta- and para-aminobenzoic acids in aqueous solutions at 298.15 K. Formation of more stable inclusion complexes between para-aminobenzoic acid and cyclodextrins was observed. The binding of aminobenzoic acids with hydroxypropyl-α-cyclodextrin was found to be enthalpy-governed owing to the prevalence of van der Waals interactions and possible H-binding. Complex formation of hydroxypropyl-β-cyclodextrin with both acids is mainly entropy driven. The increased entropy contribution observed in this case is determined by dehydration of solutes occurring during the revealed deeper insertion of aminobenzoic acids into the cavity of hydroxypropyl-β-cyclodextrin. By comparing complex formation of aminobenzoic acids with native and substituted cyclodextrins it was found that the availability of hydroxypropyl groups slightly influenced the thermodynamic parameters and did not change the binding mode or driving forces of interaction.

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Thermodynamics of azurin folding

The role of copper ion

Journal of Thermal Analysis and Calorimetry
Authors: M. Pappalardo, M. Sciacca, D. Milardi, D. Grasso, and C. La Rosa

Abstract  

The role played by the metal ion in thermodynamics of azurin folding was addressed by studying the thermal denaturation of the apo-form by differential scanning calorimetry (DSC), and by comparing the results with data concerning the holo protein. The thermal unfolding experiments showed that at 25°C the presence of metal ion increases the thermodynamic stability of azurin by 24 kJ mol−1. A comparison between the unfolding and the copper binding free energies allow us to assert that the unfolded polypeptide chain binds copper and subsequently folds into native holo azurin, being this the thermodynamically most favourable process in driving azurin folding.

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in dilute aqueous solution [ 1 ]. My remit here in this brief contribution is to give an overview of the picture now emerging of the thermodynamics of such interactions, with an attempt to understand the fundamental molecular basis for the phenomena

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