Structural parameters of 36 fluorobenzene, chlorobenzene and bromobenzene compounds were computed at the B3LYP/6-31G^＊ level with DFT method. Based on the experimental data of aqueous solubility （–lgSw） and n-octa...Structural parameters of 36 fluorobenzene, chlorobenzene and bromobenzene compounds were computed at the B3LYP/6-31G^＊ level with DFT method. Based on the experimental data of aqueous solubility （–lgSw） and n-octanol/water partition coefficient （lgKow）, using the modified theoretical linear solvation energy relation （MTLSER） model, correlation equations that can predict –lgSw and lgKow were developed using structural parameters as theoretical descriptors. The correlation coefficients （r） of these equations are 0.9728 and 0.9967, respectively. These equations were further validated by variance inflation factors （VIF） and t-test methods and then used to predict –lgSw and lgKow values. By comparison, the correlation and predictive ability of our work are more advantageous than those calculated from valence molecular connectivity indices method and molecular topology index method.展开更多
Structural parameters of 24 substituted naphthalin compounds were computed at four levels using Hartree-Fock and DFT methods. Based on the experimental data of octanol/water partition coefficient （lgKow）, three-para...Structural parameters of 24 substituted naphthalin compounds were computed at four levels using Hartree-Fock and DFT methods. Based on the experimental data of octanol/water partition coefficient （lgKow）, three-parameter （energy of the highest occupied molecular orbital （EHOMO）, the most positive, atomic net charges of molecule （q^＋） and molecular average polarizability （α）） dependent equations were developed using structural parameters as theoretical descriptors. Especially, lgKow dependent equation calculated at the HF/6-311G^＊＊ level is more advantageous than others in view of their correlation and predictive abilities. This dependent equation was validated by variance inflation factors （VIF） and t-test methods and used to predict lgKow of eight designed compounds. Upon comparison, the predictive abilities of our work are all more advantageous than those calculated from molecular property calculator program.展开更多
FeO and V2O5 are two main components of the obtained vanadium steel slag, and the reaction of FeO-V2 05 s3~stem determines the physical property of the slag. Through thermodynamic calculation and experimental study, i...FeO and V2O5 are two main components of the obtained vanadium steel slag, and the reaction of FeO-V2 05 s3~stem determines the physical property of the slag. Through thermodynamic calculation and experimental study, it can be found that within the ranges of steel-making temperature, V2O5 is reduced to VO2. As FeO exists in FeO- V2O5 system, VO2 will be reduced to V2 03 further while FeO is oxidized to Fe2O3. In this multi-system, as the content of FeO and temperature increase, the system will have products in turn such as V2O5, V2O4, FeVO4, Fe2 VO4 and Fe304. The products are mainly V3O5 and Fe203 when the content of FeO is 0.58 tool and the temperature is 1 100 K, and as the temperature increases, V2O5 starts to react with V3O5 and then generates FeVO4 ; FeVO4 disappears while the content of FeO and the temperature increase at the same time, and then Fe2 VO4 is generated by the reaction of FeO, Fe2O3 and V2O5. Iron oxides are also generated such as Fe3O4 and so on.展开更多
基金Project supported by the 973 National Basic Research Program of China (2003CB415002)the Chinese Postdoctoral Science Foundation (No. 2003033486)
文摘Structural parameters of 36 fluorobenzene, chlorobenzene and bromobenzene compounds were computed at the B3LYP/6-31G^＊ level with DFT method. Based on the experimental data of aqueous solubility （–lgSw） and n-octanol/water partition coefficient （lgKow）, using the modified theoretical linear solvation energy relation （MTLSER） model, correlation equations that can predict –lgSw and lgKow were developed using structural parameters as theoretical descriptors. The correlation coefficients （r） of these equations are 0.9728 and 0.9967, respectively. These equations were further validated by variance inflation factors （VIF） and t-test methods and then used to predict –lgSw and lgKow values. By comparison, the correlation and predictive ability of our work are more advantageous than those calculated from valence molecular connectivity indices method and molecular topology index method.
基金the China Post Doctoral Research Fund (No. 2003033486)
文摘Structural parameters of 24 substituted naphthalin compounds were computed at four levels using Hartree-Fock and DFT methods. Based on the experimental data of octanol/water partition coefficient （lgKow）, three-parameter （energy of the highest occupied molecular orbital （EHOMO）, the most positive, atomic net charges of molecule （q^＋） and molecular average polarizability （α）） dependent equations were developed using structural parameters as theoretical descriptors. Especially, lgKow dependent equation calculated at the HF/6-311G^＊＊ level is more advantageous than others in view of their correlation and predictive abilities. This dependent equation was validated by variance inflation factors （VIF） and t-test methods and used to predict lgKow of eight designed compounds. Upon comparison, the predictive abilities of our work are all more advantageous than those calculated from molecular property calculator program.
基金Item Sponsored by National Basic Research Program of China(2007CB613503)Natural Science Foundation of Chongqing City of China(CSTC)(2010BB4291)
文摘FeO and V2O5 are two main components of the obtained vanadium steel slag, and the reaction of FeO-V2 05 s3~stem determines the physical property of the slag. Through thermodynamic calculation and experimental study, it can be found that within the ranges of steel-making temperature, V2O5 is reduced to VO2. As FeO exists in FeO- V2O5 system, VO2 will be reduced to V2 03 further while FeO is oxidized to Fe2O3. In this multi-system, as the content of FeO and temperature increase, the system will have products in turn such as V2O5, V2O4, FeVO4, Fe2 VO4 and Fe304. The products are mainly V3O5 and Fe203 when the content of FeO is 0.58 tool and the temperature is 1 100 K, and as the temperature increases, V2O5 starts to react with V3O5 and then generates FeVO4 ; FeVO4 disappears while the content of FeO and the temperature increase at the same time, and then Fe2 VO4 is generated by the reaction of FeO, Fe2O3 and V2O5. Iron oxides are also generated such as Fe3O4 and so on.
