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Employing a stochastic model, both Planck and Fokker proposed almost a century ago that stoichiometric chemical reactions proceed by a chain mechanism involving discrete reaction steps. To determine whether such a chain mechanism was in fact a valid mechanism for chemical reactions was the subject of a recent study (Garfinkle, M. 2002. J. Phys. Chem. 106A: 490). Using a thermodynamic-probabilistic algorithm the stochastic reaction paths were found to be in excellent agreement with the observed reaction paths plotted from experimental data. This study was then extended to test the conclusions of Ehrenfest and Prigogine that a chain mechanism dictates that the number of discrete reaction steps required for a chemical reaction to attain equilibrium must be finite. The stochastic and empirical reaction paths were compared using experimental data for first-, second-, and third-order reactions as well as fractional order reactions. The empirical verification was excellent. Key words: chemical thermodynamics, irreversible thermodynamics, reaction kinetics, mass action, natural path. En se basant sur un modele stochastique, Plank et Fokker ont tous les deux propose independamment, il y a pratiquement un siecle, que les reactions chimiques stoechiometriques se produisent par un mecanisme en chaine impliquant des etapes reactionnelles distinctes. Un travail recent (Garfinkle, M. 2002. J. Phys. Chem. 106A: 490) a ete realise pour determiner si un tel mecanisme en chaine est un mecanisme valide pour les reactions chimiques. Sur la base d'un algorithme thermodynamique-probabilistique, on a trouve que les voies reactionnelles stochastiques sont en excellent accord avec les voies reactionnelles observees sur la base de graphiques obtenus a partir de donnees experimentales. Cette etude a alors ete etendue pour verifier la veracite des conclusions de Ehrenfest et Prigogine a l'effet qu'un mecanisme en chaine impose un nombre determine d'etapes reactionnelles distinctes necessaires pour qu'une reaction chimique atteigne un equilibre. On a compare les voies reactionnelles stochastiques et empiriques a l' aide de donnees experimentales pour des reactions d'ordre un, deux et trois ainsi que pour des reactions d'ordres fractionnaires. La verification empirique est excellente. Mots-cles : thermodynamique chimique, thermodynamique irreversible, cinetique reactionnelle, action de masse, voie naturelle. [Traduit par la Redaction], Introduction Classically, the progress of chemical reactions have been described by the empirical rate equations, first elucidated by Guldberg and Waage (see ref. 1) a century and a half ago. [...]

Carl Thompson, ed., Shipwreck in Art and Literature: Images and Interpretations from Antiquity to the Present Day (New York: Routledge, 2014), xii + 269 pp., ISBN 978-0-41564-362-7, $125.00 (hardcover). As […]

Gianni Venturi and Francesco Ceccarelli, eds. Delizie in Villa: Il Giardino Rinascimentale e i Suoi Committenti. Ferrara Paesaggio Estiense 1. Florence: Leo S. Olschki, 2008. xii + 404 pp. + [...]

Luigi Zangheri, Brunella Lorenzi, and Nausikaa M. Rahmati. Il giardino islamico. Giardini e Paesaggio 15. Florence: Leo S. Olschki, 2006. vi + 482 pp. index, append. illus. this. map. gloss. [...]