In this article VLE data for a ternary system (propylene-methanol-water) under 30～60 C,0. 3～0. 9 MPa with a mass ratio of methanol to water of 9:1, 8: 2, 7: 3 were determined with a static equilibrium still, and wer...In this article VLE data for a ternary system (propylene-methanol-water) under 30～60 C,0. 3～0. 9 MPa with a mass ratio of methanol to water of 9:1, 8: 2, 7: 3 were determined with a static equilibrium still, and were correlated by using Peng-Robinson model. The average relative error ofpropylene concentration in liquid phase is 1. 46 %. The results indicate that the models are very suitablefor the ternary system and the data are reliable.展开更多
Adsorption equilibrium isotherms of benzene in the concentrationrange of 500-4000 mg·m^-3 on two commercial activated carbons wereobtained using long-column method under 30 deg. C and differenthumidity condi- tio...Adsorption equilibrium isotherms of benzene in the concentrationrange of 500-4000 mg·m^-3 on two commercial activated carbons wereobtained using long-column method under 30 deg. C and differenthumidity condi- tions. Results show that the benzene and water vaporshave depression effects upon the adsorption of each other and thatthe unfavorable effect of water vapor resembles its single-componentisotherm on activated carbon. A com- petitive adsorption model wasproposed to explore the depression mechanisms of the non-ideal,non-similar binary adsorption systems.展开更多
The influence of solvent (in its gaseous state) on the stability of crystallized organic compounds was investigated. Through two examples of studies on the solid/vapour equilibria made in our lab, several behaviors we...The influence of solvent (in its gaseous state) on the stability of crystallized organic compounds was investigated. Through two examples of studies on the solid/vapour equilibria made in our lab, several behaviors were highlighted: (i) a new hydrated phase (thermodynamically stable) of an active pharmaceutical ingredient (API) was detected after the recrystallization starting from a deliquescent state, (ii) a spontaneous resolution of a hydrated racemic compound towards an anhydrous conglomerate can occur during the desolvation under the precise conditions of temperature and humidity. This study illustrates that knowledge about solid/vapour equilibrium is a crucial step during the complete characterization of solid organic compounds.展开更多
In this study,three semipredictive activity coefficient models:Wilson,non-random-two liquid model(NRTL),and universal quasi-chemical model(UNIQUAC),have been used for modeling vapor-liquid equilibrium properties of te...In this study,three semipredictive activity coefficient models:Wilson,non-random-two liquid model(NRTL),and universal quasi-chemical model(UNIQUAC),have been used for modeling vapor-liquid equilibrium properties of ternary mixtures that include substances found in alcoholic distillation processes of wine and musts.In particular,vapor-liquid equilibrium in ternary mixtures containing water + ethanol + congener has been modeled using parameters obtained from binary and ternary mixture data.The congeners are substances that although present in very low concentrations,of the order of part per million,are important enological parameters.The results given by these different models have been compared with literature data and conclusions about the accuracy of the models studied are drawn,recommending the best models for correlating and predicting phase equilibrium properties of this type of mixtures.展开更多
To satisfy the requirement of surface energy budget research on the meso- and micro-scale, a parameterization is developed to calculate high spatial resolution, clear-sky downward longwave radiation （DLR） from HJ-IB...To satisfy the requirement of surface energy budget research on the meso- and micro-scale, a parameterization is developed to calculate high spatial resolution, clear-sky downward longwave radiation （DLR） from HJ-IB thermal data. The DLR algorithm is established based on extensive radiative transfer simulation and statistical analysis. To address the problem that HJ-1B has a single thermal channel and lacks atmospheric information, the brightness temperature of HJ-1B and water vapor content are used in the algorithm. An accuracy evaluation and error analysis for the algorithm is conducted using a simulated radiation da- taset. The result shows that the algorithm performs well in most circumstances, but there is obvious underestimation when wa- ter vapor content is greater than 4 g/cm2. Error analysis indicates the accuracy of estimated DLRs is affected by uncertainties in input parameters, including water vapor content and top-of-atmosphere radiance. It is also affected by the difference between ground and near-surface air temperature. The algorithm is applied to actual HJ-1B data, and validated by ground data from six stations in the Heihe River and Haihe River basins. The estimated DLRs have good consistency with measured data except at Huazhaizi, and root mean square errors at most sites are around 20 W/m2, which is slightly better than the result of MODIS. There is significant overestimation of DLR at Huazhaizi during summer, which is mainly produced by the large ground-air temperature difference. A correction process based on temperature difference is proposed and applied at Huazhaizi. The result shows that the positive bias is largely diminished after correction.展开更多
Control of supersonic flow fields with shock wave is important for some industrial fields. There are many studies for control of the supersonic flow fields using active or passive control. When non-equilibrium condens...Control of supersonic flow fields with shock wave is important for some industrial fields. There are many studies for control of the supersonic flow fields using active or passive control. When non-equilibrium condensation occurs in a supersonic flow field, the flow is affected by latent heat released. Many studies for the condensation have been conducted and the characteristics have been almost clarified. Further, it was found that non-equilibrium condensation can control the flow field. In these studies, the condensation occurs across the passage of the flow field and it causes the total pressure loss in the flow field. However, local occurrence of non-equilibrium condensation in the flow field may change the characteristics of total pressure loss compared with that by the condensation across the passage of the nozzle and there are few for researches of locally occurred non-equilibrium condensation in supersonic flow field. The purpose in the present study is to clarify the effect of local occurrence of non-equilibrium condensation on the transonic flow field in a nozzle with a circular bump. As a result, local occurrence of non-equilibrium condensation reduced the shock strength and total pressure loss in the transonic flow field by flowing the moist air from trailing edge of the circular bump to the mainstream.展开更多
文摘In this article VLE data for a ternary system (propylene-methanol-water) under 30～60 C,0. 3～0. 9 MPa with a mass ratio of methanol to water of 9:1, 8: 2, 7: 3 were determined with a static equilibrium still, and were correlated by using Peng-Robinson model. The average relative error ofpropylene concentration in liquid phase is 1. 46 %. The results indicate that the models are very suitablefor the ternary system and the data are reliable.
文摘Adsorption equilibrium isotherms of benzene in the concentrationrange of 500-4000 mg·m^-3 on two commercial activated carbons wereobtained using long-column method under 30 deg. C and differenthumidity condi- tions. Results show that the benzene and water vaporshave depression effects upon the adsorption of each other and thatthe unfavorable effect of water vapor resembles its single-componentisotherm on activated carbon. A com- petitive adsorption model wasproposed to explore the depression mechanisms of the non-ideal,non-similar binary adsorption systems.
文摘The influence of solvent (in its gaseous state) on the stability of crystallized organic compounds was investigated. Through two examples of studies on the solid/vapour equilibria made in our lab, several behaviors were highlighted: (i) a new hydrated phase (thermodynamically stable) of an active pharmaceutical ingredient (API) was detected after the recrystallization starting from a deliquescent state, (ii) a spontaneous resolution of a hydrated racemic compound towards an anhydrous conglomerate can occur during the desolvation under the precise conditions of temperature and humidity. This study illustrates that knowledge about solid/vapour equilibrium is a crucial step during the complete characterization of solid organic compounds.
基金Supported by the Direction of Research of the University of La Serena-Chile (220-2-05 and 220-2-21)the National Council for Scientific and Technological Research,CONICYT (FONDECYT 3020020)
文摘In this study,three semipredictive activity coefficient models:Wilson,non-random-two liquid model(NRTL),and universal quasi-chemical model(UNIQUAC),have been used for modeling vapor-liquid equilibrium properties of ternary mixtures that include substances found in alcoholic distillation processes of wine and musts.In particular,vapor-liquid equilibrium in ternary mixtures containing water + ethanol + congener has been modeled using parameters obtained from binary and ternary mixture data.The congeners are substances that although present in very low concentrations,of the order of part per million,are important enological parameters.The results given by these different models have been compared with literature data and conclusions about the accuracy of the models studied are drawn,recommending the best models for correlating and predicting phase equilibrium properties of this type of mixtures.
基金supported by Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.KZCX2-YW-Q10-2-2)National Natural Science Foundation of China(Grant No.40971204)+1 种基金National High-tech R&D Program of China(Grant No.2012AA12A304)R&D Special Fund for Public Welfare Industry(Meteorology)(Grant No.GYHY200706046-1)
文摘To satisfy the requirement of surface energy budget research on the meso- and micro-scale, a parameterization is developed to calculate high spatial resolution, clear-sky downward longwave radiation （DLR） from HJ-IB thermal data. The DLR algorithm is established based on extensive radiative transfer simulation and statistical analysis. To address the problem that HJ-1B has a single thermal channel and lacks atmospheric information, the brightness temperature of HJ-1B and water vapor content are used in the algorithm. An accuracy evaluation and error analysis for the algorithm is conducted using a simulated radiation da- taset. The result shows that the algorithm performs well in most circumstances, but there is obvious underestimation when wa- ter vapor content is greater than 4 g/cm2. Error analysis indicates the accuracy of estimated DLRs is affected by uncertainties in input parameters, including water vapor content and top-of-atmosphere radiance. It is also affected by the difference between ground and near-surface air temperature. The algorithm is applied to actual HJ-1B data, and validated by ground data from six stations in the Heihe River and Haihe River basins. The estimated DLRs have good consistency with measured data except at Huazhaizi, and root mean square errors at most sites are around 20 W/m2, which is slightly better than the result of MODIS. There is significant overestimation of DLR at Huazhaizi during summer, which is mainly produced by the large ground-air temperature difference. A correction process based on temperature difference is proposed and applied at Huazhaizi. The result shows that the positive bias is largely diminished after correction.
文摘Control of supersonic flow fields with shock wave is important for some industrial fields. There are many studies for control of the supersonic flow fields using active or passive control. When non-equilibrium condensation occurs in a supersonic flow field, the flow is affected by latent heat released. Many studies for the condensation have been conducted and the characteristics have been almost clarified. Further, it was found that non-equilibrium condensation can control the flow field. In these studies, the condensation occurs across the passage of the flow field and it causes the total pressure loss in the flow field. However, local occurrence of non-equilibrium condensation in the flow field may change the characteristics of total pressure loss compared with that by the condensation across the passage of the nozzle and there are few for researches of locally occurred non-equilibrium condensation in supersonic flow field. The purpose in the present study is to clarify the effect of local occurrence of non-equilibrium condensation on the transonic flow field in a nozzle with a circular bump. As a result, local occurrence of non-equilibrium condensation reduced the shock strength and total pressure loss in the transonic flow field by flowing the moist air from trailing edge of the circular bump to the mainstream.
