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Modification of the stokes – einstein equation with a semiempirical microfriction factor for correlation of tracer diffusivities in organic solvents / Shaw H. Chen in Industrial & engineering chemistry research, Vol. 50 N° 21 (Novembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 21 (Novembre 2011) . - pp. 12304-12310 Titre : Modification of the stokes – einstein equation with a semiempirical microfriction factor for correlation of tracer diffusivities in organic solvents Type de document : texte imprimé Auteurs : Shaw H. Chen, Auteur ; Simon K.-H. Wei, Auteur Année de publication : 2011 Article en page(s) : pp. 12304-12310 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Organic  solvent  Diffusion  coefficient  Tracers  Correlation  analysis  Correlation  Semiempirical  method Résumé : Characterized by conceptual simplicity, a semiempirical formula based on the Stokes-Einstein equation and microfriction theory was constructed for correlating tracer diffusivities and, alternatively, for evaluating solute aggregation in organic solvents. For nonassociated systems, van der Waals radii determined by Bondi's method were adopted to establish a base equation for treating associated solvents and solute-solvent systems. Values of molecular association numbers for hydrogen-bonded solvents are in good agreement with those characterized by X-ray diffraction and near-infrared spectroscopy. The generalized equation incorporating independently evaluated solutes' solvation numbers and solvents' association numbers as needed is capable of predicting tracer diffusivities to within ±8% for nonassociated and associated solute-solvent systems without resorting to adjustable parameters. Overall, this new approach perfohttp://acatalogue_2.biblio.intranet.enp.edu.dz/catalog.php?categ=serials&sub=analysis&action=analysis_form&bul_id=15683&analysis_id=0rms better than the widely used Wilke-Chang equation with a comparable level of simplicity, including delineating temperature dependencies from 298 to 473 K of tracer diffusivities of solute-solvent systems consisting of relatively compact molecules. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24697553 [article] Modification of the stokes – einstein equation with a semiempirical microfriction factor for correlation of tracer diffusivities in organic solvents [texte imprimé] / Shaw H. Chen, Auteur ; Simon K.-H. Wei, Auteur . - 2011 . - pp. 12304-12310. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 21 (Novembre 2011) . - pp. 12304-12310 Mots-clés : Organic  solvent  Diffusion  coefficient  Tracers  Correlation  analysis  Correlation  Semiempirical  method Résumé : Characterized by conceptual simplicity, a semiempirical formula based on the Stokes-Einstein equation and microfriction theory was constructed for correlating tracer diffusivities and, alternatively, for evaluating solute aggregation in organic solvents. For nonassociated systems, van der Waals radii determined by Bondi's method were adopted to establish a base equation for treating associated solvents and solute-solvent systems. Values of molecular association numbers for hydrogen-bonded solvents are in good agreement with those characterized by X-ray diffraction and near-infrared spectroscopy. The generalized equation incorporating independently evaluated solutes' solvation numbers and solvents' association numbers as needed is capable of predicting tracer diffusivities to within ±8% for nonassociated and associated solute-solvent systems without resorting to adjustable parameters. Overall, this new approach perfohttp://acatalogue_2.biblio.intranet.enp.edu.dz/catalog.php?categ=serials&sub=analysis&action=analysis_form&bul_id=15683&analysis_id=0rms better than the widely used Wilke-Chang equation with a comparable level of simplicity, including delineating temperature dependencies from 298 to 473 K of tracer diffusivities of solute-solvent systems consisting of relatively compact molecules. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24697553