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Modelling of the batch sucrose crystallization kinetics using artificial neural networks / K. Vasanth Kumar in Industrial & engineering chemistry research, Vol. 47 n°14 (Juillet 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°14 (Juillet 2008) . - p. 4917–4923 Titre : Modelling of the batch sucrose crystallization kinetics using artificial neural networks : comparison with conventional regression analysis Type de document : texte imprimé Auteurs : K. Vasanth Kumar, Auteur ; P. Martins, Auteur ; F. Rocha, Auteur Année de publication : 2008 Article en page(s) : p. 4917–4923 Langues : Anglais (eng) Mots-clés : Sucrose;  Artificial  neural  network;  Correlation Résumé : A three-layer feed-forward artificial neural network (ANN) was constructed and tested to analyze the crystal growth rate of sucrose under different operating conditions. The operating variables studied were used as inputs to predict the corresponding crystal growth rate. The operating variables studied include the supersaturation, temperature, agitation speed, and seed crystal diameter. The constructed ANN was determined to be precise in modeling the crystal growth rate for any operating conditions. The constructed network was also found to be precise in predicting the crystal growth rate for the new input data, which are kept unaware of the trained neural network, showing its applicability to determine the growth rate for any operating conditions of interest. The ANN-predicted crystal growth rates were compared to those from the conventional nonlinear regression analysis. The ANN was observed to be more accurate in predicting the crystal growth rate, irrespective of the operating conditions studied. The correlation coefficients between the experimentally determined crystal growth rate and the crystal growth rates determined by the ANN and multiple nonlinear regression (MNLR) were determined to be 0.999 and 0.748, respectively. The correlation coefficient between the experimentally determined crystal growth rates and the crystal growth rates determined by the ANN for new inputs was observed to be >0.98. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie701706v [article] Modelling of the batch sucrose crystallization kinetics using artificial neural networks : comparison with conventional regression analysis [texte imprimé] / K. Vasanth Kumar, Auteur ; P. Martins, Auteur ; F. Rocha, Auteur . - 2008 . - p. 4917–4923. Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°14 (Juillet 2008) . - p. 4917–4923 Mots-clés : Sucrose;  Artificial  neural  network;  Correlation Résumé : A three-layer feed-forward artificial neural network (ANN) was constructed and tested to analyze the crystal growth rate of sucrose under different operating conditions. The operating variables studied were used as inputs to predict the corresponding crystal growth rate. The operating variables studied include the supersaturation, temperature, agitation speed, and seed crystal diameter. The constructed ANN was determined to be precise in modeling the crystal growth rate for any operating conditions. The constructed network was also found to be precise in predicting the crystal growth rate for the new input data, which are kept unaware of the trained neural network, showing its applicability to determine the growth rate for any operating conditions of interest. The ANN-predicted crystal growth rates were compared to those from the conventional nonlinear regression analysis. The ANN was observed to be more accurate in predicting the crystal growth rate, irrespective of the operating conditions studied. The correlation coefficients between the experimentally determined crystal growth rate and the crystal growth rates determined by the ANN and multiple nonlinear regression (MNLR) were determined to be 0.999 and 0.748, respectively. The correlation coefficient between the experimentally determined crystal growth rates and the crystal growth rates determined by the ANN for new inputs was observed to be >0.98. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie701706v

Neural network prediction of interfacial tension at crystal/solution interface / K. Vasanth Kumar in Industrial & engineering chemistry research, Vol. 48 N° 8 (Avril 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 8 (Avril 2009) . - pp. 4160–4164 Titre : Neural network prediction of interfacial tension at crystal/solution interface Type de document : texte imprimé Auteurs : K. Vasanth Kumar, Auteur Année de publication : 2009 Article en page(s) : pp. 4160–4164 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Interfacial  tension  Crystal/liquid  interface  oSL  Crystal  growth  kinetics  Neural  network Résumé : Interfacial tension at the crystal/liquid interface is a crucial and important parameter in crystal growth kinetics. The objective of the present study is to develop a neural network that is simple to use for predicting this important parameter using only from the information of solubility, molecular weight, and density of the studied systems. A three-layer feed-forward neural network was constructed and tested to predict the interfacial tension at the crystal/solution interface. The concentration of solute in liquid phase, concentration of solute in solid phase, temperature, density and molecular weight of crystal were used as inputs to predict the interfacial tension at the crystal/liquid interface (σSL). The network was trained using the solubility information for 28 systems to predict the σSL value and was validated with 29 new systems. Despite the limited number of data used for training, the neural network was capable of predicting σSL successfully for the new inputs, which are kept unaware during the training process. The σSL value that is predicted by the artificial neural network during the training and testing process was compared with σSL predicted from the widely used empirical expression. For most of the systems, ANN better predicts σSL, when compared to empirical correlation. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801666u [article] Neural network prediction of interfacial tension at crystal/solution interface [texte imprimé] / K. Vasanth Kumar, Auteur . - 2009 . - pp. 4160–4164. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 8 (Avril 2009) . - pp. 4160–4164 Mots-clés : Interfacial  tension  Crystal/liquid  interface  oSL  Crystal  growth  kinetics  Neural  network Résumé : Interfacial tension at the crystal/liquid interface is a crucial and important parameter in crystal growth kinetics. The objective of the present study is to develop a neural network that is simple to use for predicting this important parameter using only from the information of solubility, molecular weight, and density of the studied systems. A three-layer feed-forward neural network was constructed and tested to predict the interfacial tension at the crystal/solution interface. The concentration of solute in liquid phase, concentration of solute in solid phase, temperature, density and molecular weight of crystal were used as inputs to predict the interfacial tension at the crystal/liquid interface (σSL). The network was trained using the solubility information for 28 systems to predict the σSL value and was validated with 29 new systems. Despite the limited number of data used for training, the neural network was capable of predicting σSL successfully for the new inputs, which are kept unaware during the training process. The σSL value that is predicted by the artificial neural network during the training and testing process was compared with σSL predicted from the widely used empirical expression. For most of the systems, ANN better predicts σSL, when compared to empirical correlation. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801666u

A Pseudo second - order kinetic expression for dissolution kinetic profiles of solids in solutions / K. Vasanth Kumar in Industrial & engineering chemistry research, Vol. 49 N° 16 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp 7257–7262 Titre : A Pseudo second - order kinetic expression for dissolution kinetic profiles of solids in solutions Type de document : texte imprimé Auteurs : K. Vasanth Kumar, Auteur ; Issam A. Khaddour, Auteur ; Vinod K. Gupta, Auteur Année de publication : 2010 Article en page(s) : pp 7257–7262 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Kinetic  Solids Résumé : A pseudo second-order kinetic expression was presented to explain the dissolution kinetics of solids in solution. The kinetic constant, initial dissolution rate, and theoretical saturation concentration according to pseudo second-order kinetic expression was defined. The proposed expression successfully represents the published dissolution kinetic profiles of alumina, digoxin, benzoic acid, lead chloride, and lecithin in solutions. A pseudo second-order kinetics based on fractional conversion successfully represents the dissolution kinetics of ulexite in ammonium acetate solutions. The pseudo second-order kinetics enabled the prediction of dissolution kinetics for higher residence time from experimental data obtained in relatively short time. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1010228 [article] A Pseudo second - order kinetic expression for dissolution kinetic profiles of solids in solutions [texte imprimé] / K. Vasanth Kumar, Auteur ; Issam A. Khaddour, Auteur ; Vinod K. Gupta, Auteur . - 2010 . - pp 7257–7262. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp 7257–7262 Mots-clés : Kinetic  Solids Résumé : A pseudo second-order kinetic expression was presented to explain the dissolution kinetics of solids in solution. The kinetic constant, initial dissolution rate, and theoretical saturation concentration according to pseudo second-order kinetic expression was defined. The proposed expression successfully represents the published dissolution kinetic profiles of alumina, digoxin, benzoic acid, lead chloride, and lecithin in solutions. A pseudo second-order kinetics based on fractional conversion successfully represents the dissolution kinetics of ulexite in ammonium acetate solutions. The pseudo second-order kinetics enabled the prediction of dissolution kinetics for higher residence time from experimental data obtained in relatively short time. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1010228

Regression analysis for the two-step growth kinetics of crystals in pure solutions / K. Vasanth Kumar in Industrial & engineering chemistry research, Vol. 48 N° 16 (Août 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 16 (Août 2009) . - pp. 7852–7859 Titre : Regression analysis for the two-step growth kinetics of crystals in pure solutions Type de document : texte imprimé Auteurs : K. Vasanth Kumar, Auteur Année de publication : 2009 Article en page(s) : pp. 7852–7859 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Growth  kinetics  Crystals  Pure  solutions  Mass  transfer  model Résumé : The overall growth kinetics of ammonium pentaborate, borax decahydrate, and boric acid crystals in pure solutions were analyzed using a two-step mass transfer model. Four different linear expressions of the two-step mass transfer model (TSM), which include the widely used expressions of Sobczak and Karpinski, were discussed. The influence of linearization for an assumed second-order reaction kinetics on the mass transfer and reaction steps was studied for various crystallization systems with overall growth kinetic order ranging from 1 to ≥2. The overall growth kinetics of ammonium pentaborate and borax decahydrate were used to study the effect of linearization as a function of temperature and seed size. The complexities in using the linearized TSM expression to predict the mechanism of the crystal growth process in pure solutions were discussed. A Type 3 expression of Karpinski that successfully represents the overall crystal growth kinetics was determined to be successful in representing two-step growth of borax decahydrate and ammonium pentaborate crystals. Type 1 and Type 4 expressions were determined to be inappropriate for the studied crystallization systems, because they either poorly fit the growth kinetics or produce kinetic parameters without physical meaning. The Sobczak expression well-represents the overall crystal growth kinetics of second order or more, and the Karpinski expression was determined to be successful in representing the overall crystal growth kinetics of order near or equal to unity. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9002975 [article] Regression analysis for the two-step growth kinetics of crystals in pure solutions [texte imprimé] / K. Vasanth Kumar, Auteur . - 2009 . - pp. 7852–7859. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 16 (Août 2009) . - pp. 7852–7859 Mots-clés : Growth  kinetics  Crystals  Pure  solutions  Mass  transfer  model Résumé : The overall growth kinetics of ammonium pentaborate, borax decahydrate, and boric acid crystals in pure solutions were analyzed using a two-step mass transfer model. Four different linear expressions of the two-step mass transfer model (TSM), which include the widely used expressions of Sobczak and Karpinski, were discussed. The influence of linearization for an assumed second-order reaction kinetics on the mass transfer and reaction steps was studied for various crystallization systems with overall growth kinetic order ranging from 1 to ≥2. The overall growth kinetics of ammonium pentaborate and borax decahydrate were used to study the effect of linearization as a function of temperature and seed size. The complexities in using the linearized TSM expression to predict the mechanism of the crystal growth process in pure solutions were discussed. A Type 3 expression of Karpinski that successfully represents the overall crystal growth kinetics was determined to be successful in representing two-step growth of borax decahydrate and ammonium pentaborate crystals. Type 1 and Type 4 expressions were determined to be inappropriate for the studied crystallization systems, because they either poorly fit the growth kinetics or produce kinetic parameters without physical meaning. The Sobczak expression well-represents the overall crystal growth kinetics of second order or more, and the Karpinski expression was determined to be successful in representing the overall crystal growth kinetics of order near or equal to unity. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9002975

A semiempirical kinetics for modeling and simulation of the crystal growth process in pure solutions / K. Vasanth Kumar in Industrial & engineering chemistry research, Vol. 48 N° 10 (Mai 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 10 (Mai 2009) . - pp. 5105–5110 Titre : A semiempirical kinetics for modeling and simulation of the crystal growth process in pure solutions Type de document : texte imprimé Auteurs : K. Vasanth Kumar, Auteur Année de publication : 2009 Article en page(s) : pp. 5105–5110 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Crystal  growth  Kinetics  Solid-phase  concentration  Crystallization  rate Résumé : A kinetic model was proposed to explain the growth of crystals in pure solutions based on the solid-phase concentration, assuming that the crystal growth process follows a pseudo-second-order kinetics. The initial crystallization rate was defined based on the pseudo-second-order kinetics. The proposed model was determined to be useful in predicting the rate constant, the solid-phase concentration at equilibrium, and the initial crystallization rate. The pseudo-second-order kinetic model was applied to the experimental data of the sucrose crystal growth process for different operating temperatures and seed crystal diameters. The proposed model was accurate in modeling the experimental kinetics of sucrose crystallization process for the range of operating conditions studied. The coefficient of determination between experimental data and predicted kinetics varied from r2 = 0.943 to r2 = 0.982 at the studied temperatures. The calculated kinetic parameters were used to generate three-dimensional empirical correlations relating the crystal growth of sucrose for the range of temperature studied. The proposed model was very simple with only two unknown parameters, which can be easily determined by a simple linear or nonlinear regression analysis. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8018565 [article] A semiempirical kinetics for modeling and simulation of the crystal growth process in pure solutions [texte imprimé] / K. Vasanth Kumar, Auteur . - 2009 . - pp. 5105–5110. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 10 (Mai 2009) . - pp. 5105–5110 Mots-clés : Crystal  growth  Kinetics  Solid-phase  concentration  Crystallization  rate Résumé : A kinetic model was proposed to explain the growth of crystals in pure solutions based on the solid-phase concentration, assuming that the crystal growth process follows a pseudo-second-order kinetics. The initial crystallization rate was defined based on the pseudo-second-order kinetics. The proposed model was determined to be useful in predicting the rate constant, the solid-phase concentration at equilibrium, and the initial crystallization rate. The pseudo-second-order kinetic model was applied to the experimental data of the sucrose crystal growth process for different operating temperatures and seed crystal diameters. The proposed model was accurate in modeling the experimental kinetics of sucrose crystallization process for the range of operating conditions studied. The coefficient of determination between experimental data and predicted kinetics varied from r2 = 0.943 to r2 = 0.982 at the studied temperatures. The calculated kinetic parameters were used to generate three-dimensional empirical correlations relating the crystal growth of sucrose for the range of temperature studied. The proposed model was very simple with only two unknown parameters, which can be easily determined by a simple linear or nonlinear regression analysis. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8018565

Simple kinetic expressions to study the transport process during the growth of crystals in solution / K. Vasanth Kumar in Industrial & engineering chemistry research, Vol. 48 N° 24 (Décembre 2009) 

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Simple kinetic expressions to study the transport process during the growth of crystals in solution / K. Vasanth Kumar in Industrial & engineering chemistry research, Vol. 48 N° 24 (Décembre 2009) 

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