A novel method named two-level group contribution (GC-K) method for the estimation of octanol-water partition coefficient (Kow) of chloride hydrocarbon is presented. The equation includes only normal boiling point...A novel method named two-level group contribution (GC-K) method for the estimation of octanol-water partition coefficient (Kow) of chloride hydrocarbon is presented. The equation includes only normal boiling points and molecular weight of compounds. Group contribution parameters of 12 first-level groups and 7 second-level groups for Kow are obtained by correlating experimental data of three types including 57 compounds. By comparing the estimation results of the first-level with that of the two-level groups, it was observed that the latter is better with the addition of the modification of proximity effects. When compared with Marrero's three-level group contribution approach and atom-fragment contribution method (AFC), the accuracy of the average relative error of GC-K by first-level groups is 7.20% and is preferred to other methods.展开更多
Based on the analysis of the principles of heat and mass transfer from the liquid bulk to bubble surface during nucleation, a new estimation method to predict the heat transfer of the nucleate pool boiling in binary m...Based on the analysis of the principles of heat and mass transfer from the liquid bulk to bubble surface during nucleation, a new estimation method to predict the heat transfer of the nucleate pool boiling in binary mixtures is proposed in this paper by using the heat and mass transfer analogy (Colburn analogy) at the bubble surface transfer layers. With the use of Thome's concept of boiling range, an approximate method is derived to realize the calculation. The predicted results by this method are in good agreement with the experimental data from different sources.展开更多
Boiling of water/triethyleneglycol(TEG)binary solution has a wide-ranging application in the gas processing engineering.Design,operation and optimization of the involved boilers require accurate prediction of boiling ...Boiling of water/triethyleneglycol(TEG)binary solution has a wide-ranging application in the gas processing engineering.Design,operation and optimization of the involved boilers require accurate prediction of boiling heat transfer coefficient between surface and solution.In this investigation,nucleate pool boiling heat transfer coefficient has been experimentally measured on a horizontal rod heater in water/TEG binary solutions in a wide range of concentrations and heat fluxes under ambient condition.The present experimental data are correlated using major existing correlations.In addition a correlation is presented for prediction of pool boiling heat transfer for the system in which the vapour pressure of one component is negligible.This model is based on the mass transfer rate equation for prediction of the concentration at the bubble vapor/liquid interface.Based on this prediction,the temperature of the interface and accordingly,the boiling heat transfer coefficient could be straightforwardly calculated from the known concentration at the interface.It is shown that this simple model has sufficient accuracy and is acceptable below the medium concentrations of TEG when the vapor equilibrium concentration of TEG is almost zero.The presented model excludes any tuning parameter and requires very few physical properties to apply.展开更多
A novel triolein-embedded adsorbent for re-moval of persistent organic pollutants (POPs) from water was developed. In this paper, taking dieldrin and endrin as the target pollutants, different factors (temperature, io...A novel triolein-embedded adsorbent for re-moval of persistent organic pollutants (POPs) from water was developed. In this paper, taking dieldrin and endrin as the target pollutants, different factors (temperature, ion strength, pH, and concentration of humic acid) that affect the adsorption rate were investigated. Adsorption isotherms of these two pollutants fitted to Freundlich model well identi-fied the partition mechanism between the adsorbent and water. However, the equilibrium constant of dieldrin was larger than that of endrin due to larger octanol-water coeffi-cient of dieldrin. Adsorption rate of dieldrin increased with the increase of temperature, the decrease of ion strength, pH and concentration of humic acid, whereas adsorption rate of endrin decreased with the increase of temperature and pH. Humic acid firstly increased, and then decreased the adsorp-tion rate of endrin. Ion strength hardly affected the adsorp-tion rate of endrin.展开更多
文摘A novel method named two-level group contribution (GC-K) method for the estimation of octanol-water partition coefficient (Kow) of chloride hydrocarbon is presented. The equation includes only normal boiling points and molecular weight of compounds. Group contribution parameters of 12 first-level groups and 7 second-level groups for Kow are obtained by correlating experimental data of three types including 57 compounds. By comparing the estimation results of the first-level with that of the two-level groups, it was observed that the latter is better with the addition of the modification of proximity effects. When compared with Marrero's three-level group contribution approach and atom-fragment contribution method (AFC), the accuracy of the average relative error of GC-K by first-level groups is 7.20% and is preferred to other methods.
文摘Based on the analysis of the principles of heat and mass transfer from the liquid bulk to bubble surface during nucleation, a new estimation method to predict the heat transfer of the nucleate pool boiling in binary mixtures is proposed in this paper by using the heat and mass transfer analogy (Colburn analogy) at the bubble surface transfer layers. With the use of Thome's concept of boiling range, an approximate method is derived to realize the calculation. The predicted results by this method are in good agreement with the experimental data from different sources.
文摘Boiling of water/triethyleneglycol(TEG)binary solution has a wide-ranging application in the gas processing engineering.Design,operation and optimization of the involved boilers require accurate prediction of boiling heat transfer coefficient between surface and solution.In this investigation,nucleate pool boiling heat transfer coefficient has been experimentally measured on a horizontal rod heater in water/TEG binary solutions in a wide range of concentrations and heat fluxes under ambient condition.The present experimental data are correlated using major existing correlations.In addition a correlation is presented for prediction of pool boiling heat transfer for the system in which the vapour pressure of one component is negligible.This model is based on the mass transfer rate equation for prediction of the concentration at the bubble vapor/liquid interface.Based on this prediction,the temperature of the interface and accordingly,the boiling heat transfer coefficient could be straightforwardly calculated from the known concentration at the interface.It is shown that this simple model has sufficient accuracy and is acceptable below the medium concentrations of TEG when the vapor equilibrium concentration of TEG is almost zero.The presented model excludes any tuning parameter and requires very few physical properties to apply.
基金This work was supported by the National Natural Science Foundation of China(Grant No.20337020)the National High-Tech Research and Development Plan(Grant No.2005AA642020)the China Postdoctoral Science Foundation.
文摘A novel triolein-embedded adsorbent for re-moval of persistent organic pollutants (POPs) from water was developed. In this paper, taking dieldrin and endrin as the target pollutants, different factors (temperature, ion strength, pH, and concentration of humic acid) that affect the adsorption rate were investigated. Adsorption isotherms of these two pollutants fitted to Freundlich model well identi-fied the partition mechanism between the adsorbent and water. However, the equilibrium constant of dieldrin was larger than that of endrin due to larger octanol-water coeffi-cient of dieldrin. Adsorption rate of dieldrin increased with the increase of temperature, the decrease of ion strength, pH and concentration of humic acid, whereas adsorption rate of endrin decreased with the increase of temperature and pH. Humic acid firstly increased, and then decreased the adsorp-tion rate of endrin. Ion strength hardly affected the adsorp-tion rate of endrin.