In the paper, an estimating method for critical properties in group-contribution method is presented.For eliminating the influence of adjacent group and distinguishing isomers, the new method including first-level gro...In the paper, an estimating method for critical properties in group-contribution method is presented.For eliminating the influence of adjacent group and distinguishing isomers, the new method including first-level group-contribution method and second-level group-contribution method is proposed. The new method demonstrates significant improvement in accuracy.展开更多
The vaporization ratios of the slurry at various temperature and partial pressure were calculated with the group-contribution method,and then the phase state of the slurry in the residue fluid catalytic cracking(RFCC)...The vaporization ratios of the slurry at various temperature and partial pressure were calculated with the group-contribution method,and then the phase state of the slurry in the residue fluid catalytic cracking(RFCC) disengager was determined.This research could provide some advices on how to select the technological conditions to decrease the coking in the RFCC disengager.The oil gas temperature and the slurry partial pressure had signifi- cant effects on the vaporization ratio of the slurry.Increasing the oil gas temperature and reducing the slurry partial pressure could effectively slow down the coking speed in the RFCC disengager.According to the calculation results, a correlation was established to predict the vaporization ratio of the slurry under different operating conditions.展开更多
The enthalpies of formation of solid organic compounds containing carbon,nitrogen,oxygen,and hydrogen were estimated using two suggested descriptor sets,separately,by machine learning methods.The two descriptor sets a...The enthalpies of formation of solid organic compounds containing carbon,nitrogen,oxygen,and hydrogen were estimated using two suggested descriptor sets,separately,by machine learning methods.The two descriptor sets are both composed of descriptors of Benson’s groups and corrected groups.The main differences between them are that one is generated based on atoms and the other is based on bonds.An in-house program was specially written in Java to extract all the descriptors with a function to ensure that each atom(or bond)of a molecule is represented by Benson’s groups once for an atom-based(or bond-based)descriptor set.Multiple linear regression and partial least squares were used,separately,to build models to predict the enthalpy of formation for two descriptor sets.The combination of the models constructed by two descriptor sets based on the atoms and the bonds achieved the best-predicted results in this paper,and the corresponding results of the test set are better than that in the literature,from which the original data were retrieved.Further,a small data set of fluorinated molecules was collected,and satisfactory results were also obtained for these molecules containing fluorine with the assistance of the former data set.展开更多
基金Supported by Tianjin Natural Scientific Foundation(No.973602911).
文摘In the paper, an estimating method for critical properties in group-contribution method is presented.For eliminating the influence of adjacent group and distinguishing isomers, the new method including first-level group-contribution method and second-level group-contribution method is proposed. The new method demonstrates significant improvement in accuracy.
基金Supported by the National-Natural Science Foundation of China （No.20406013） and Program for New Century Excellent Talents in University （No.NCET-04-0107）.
文摘The vaporization ratios of the slurry at various temperature and partial pressure were calculated with the group-contribution method,and then the phase state of the slurry in the residue fluid catalytic cracking(RFCC) disengager was determined.This research could provide some advices on how to select the technological conditions to decrease the coking in the RFCC disengager.The oil gas temperature and the slurry partial pressure had signifi- cant effects on the vaporization ratio of the slurry.Increasing the oil gas temperature and reducing the slurry partial pressure could effectively slow down the coking speed in the RFCC disengager.According to the calculation results, a correlation was established to predict the vaporization ratio of the slurry under different operating conditions.
基金Open Research Fund Program of Science and Technology on Aerospace Chemical Power Laboratory,China(No.120201B01)National Natural Science Foundation of China(Nos.21875061,21975066).
文摘The enthalpies of formation of solid organic compounds containing carbon,nitrogen,oxygen,and hydrogen were estimated using two suggested descriptor sets,separately,by machine learning methods.The two descriptor sets are both composed of descriptors of Benson’s groups and corrected groups.The main differences between them are that one is generated based on atoms and the other is based on bonds.An in-house program was specially written in Java to extract all the descriptors with a function to ensure that each atom(or bond)of a molecule is represented by Benson’s groups once for an atom-based(or bond-based)descriptor set.Multiple linear regression and partial least squares were used,separately,to build models to predict the enthalpy of formation for two descriptor sets.The combination of the models constructed by two descriptor sets based on the atoms and the bonds achieved the best-predicted results in this paper,and the corresponding results of the test set are better than that in the literature,from which the original data were retrieved.Further,a small data set of fluorinated molecules was collected,and satisfactory results were also obtained for these molecules containing fluorine with the assistance of the former data set.
