In our previous paper we extended the Tao and Mason equation of state (TM EOS) to refrigerant fluids, using the speed of sound data. This is a continuation for evaluating TM EOS in predicting PVT properties of heavy n...In our previous paper we extended the Tao and Mason equation of state (TM EOS) to refrigerant fluids, using the speed of sound data. This is a continuation for evaluating TM EOS in predicting PVT properties of heavy n-alkanes. Liquid density of long-chain n-alkane systems from C 9 to C 20 have been calculated using an analytical equation of state based on the statistical-mechanical perturbation theory. The second virial coefficients of these n-alkanes are scarce and there is no accurate potential energy function for their theoretical calculation. In this work the second virial coefficients are calculated using a corresponding state correlation based on surface tension and liquid density at the freezing point. The deviation of calculated densities of these alkanes is within 0.5% from experimental data. The densities of n-alkanes obtained from the TM EOS are compared with those calculated from Ihm-Song-Mason equation of state and the corresponding-states liquid densities (COSTALD). Our results are in favor of the preference of the TM EOS over other two equations of state.展开更多
Structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints are investigated. Appell equations and differential equations of motion for holonomi...Structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints are investigated. Appell equations and differential equations of motion for holonomie mechanic systems with unilateral constraints axe established. The definition and the criterion of Mei symmetry for Appell equations in holonomic systems with unilateral constraints under the infinitesimal transformations of groups axe also given. The expressions of the structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints expressed by Appell functions are obtained. An example is given to illustrate the application of the results.展开更多
Different studies show that the altitude regions of the State of Santa Catarina have great potential for the production of grapevine varieties. The aim of this study was to characterize the phenological development, d...Different studies show that the altitude regions of the State of Santa Catarina have great potential for the production of grapevine varieties. The aim of this study was to characterize the phenological development, determine the thermal requirements in degree-days （DD）, the index heliothermic （IH） and climatic variables during the vegetative and productive development of varieties Merlot and Cabernet Sauvignon grown in Campo Belo do Sul （27°40′04″ S, 50°44′48″ W, altitude 950 m a.s.l.） and Sao Joaquim （28°15′13″ S, 49°57′02″ W, altitude 1,400 m a.s.l.） during 2012/2013 cycle. Phenological stages evaluated were bud break, full bloom, veraison and maturity. Higher temperatures, global radiation, PAR and lower volumes of rainfall were the main climatic parameters that differentiated Campo Belo do Sul from Sao Joaquim. Due to occurrence of higher temperatures, Campo Belo do Sul presented thermal summation around 40% higher than Sao Joaquim. The low temperatures of Sao Joaquim extended the period of grape ripening and were responsible for the highest levels of titratable acidity and the higher concentrations of anthocyanins and total polyphenols in both varieties. The results show that in the altitude ranges studied （900 and 1400 m）, climatic behavior and viticultural performance of Cabernet Sauvignon and Merlot were suitable for producing quality wines.展开更多
基金H. Karimi and F. Yousefi would like to thank Yasouj University for supporting this project
文摘In our previous paper we extended the Tao and Mason equation of state (TM EOS) to refrigerant fluids, using the speed of sound data. This is a continuation for evaluating TM EOS in predicting PVT properties of heavy n-alkanes. Liquid density of long-chain n-alkane systems from C 9 to C 20 have been calculated using an analytical equation of state based on the statistical-mechanical perturbation theory. The second virial coefficients of these n-alkanes are scarce and there is no accurate potential energy function for their theoretical calculation. In this work the second virial coefficients are calculated using a corresponding state correlation based on surface tension and liquid density at the freezing point. The deviation of calculated densities of these alkanes is within 0.5% from experimental data. The densities of n-alkanes obtained from the TM EOS are compared with those calculated from Ihm-Song-Mason equation of state and the corresponding-states liquid densities (COSTALD). Our results are in favor of the preference of the TM EOS over other two equations of state.
基金Supported by the National Natural Science Foundation of China under Grant No.10572021the Preparatory Research Foundation of Jiangnan University under Grant No.2008LYY011
文摘Structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints are investigated. Appell equations and differential equations of motion for holonomie mechanic systems with unilateral constraints axe established. The definition and the criterion of Mei symmetry for Appell equations in holonomic systems with unilateral constraints under the infinitesimal transformations of groups axe also given. The expressions of the structural equation and Mei conserved quantity of Mei symmetry for Appell equations in holonomic systems with unilateral constraints expressed by Appell functions are obtained. An example is given to illustrate the application of the results.
文摘Different studies show that the altitude regions of the State of Santa Catarina have great potential for the production of grapevine varieties. The aim of this study was to characterize the phenological development, determine the thermal requirements in degree-days （DD）, the index heliothermic （IH） and climatic variables during the vegetative and productive development of varieties Merlot and Cabernet Sauvignon grown in Campo Belo do Sul （27°40′04″ S, 50°44′48″ W, altitude 950 m a.s.l.） and Sao Joaquim （28°15′13″ S, 49°57′02″ W, altitude 1,400 m a.s.l.） during 2012/2013 cycle. Phenological stages evaluated were bud break, full bloom, veraison and maturity. Higher temperatures, global radiation, PAR and lower volumes of rainfall were the main climatic parameters that differentiated Campo Belo do Sul from Sao Joaquim. Due to occurrence of higher temperatures, Campo Belo do Sul presented thermal summation around 40% higher than Sao Joaquim. The low temperatures of Sao Joaquim extended the period of grape ripening and were responsible for the highest levels of titratable acidity and the higher concentrations of anthocyanins and total polyphenols in both varieties. The results show that in the altitude ranges studied （900 and 1400 m）, climatic behavior and viticultural performance of Cabernet Sauvignon and Merlot were suitable for producing quality wines.
