A theoretical model on the solvus line prediction of a film was proposed and applied to a nanogranular A1-Cu system. The calculation results show that the solvus line of solute Cu will markedly lower with the decrease...A theoretical model on the solvus line prediction of a film was proposed and applied to a nanogranular A1-Cu system. The calculation results show that the solvus line of solute Cu will markedly lower with the decrease of grain size, namely, the starting temperature of θ (Al2Cu) precipitation in a nanogranular A1-Cu film will markedly lower than that of conventional coarse grain alloy with the same Cu concentration, and the precipitation temperatures calculated are comparable with the experimental ones. The theoretical model can be simply used to calculate the starting temperature of precipitation in A1-Cu films under three states: ① films with substrate; ②films without substrate; ③ultrafine grain bulk alloy. As a result, the model is universal, moreover, can be, in principle, used to predict precipitation temperature in other systems.展开更多
A molecular thermodynamic model of polyelectrolyte developed previously was extended to polyelectrolyte solutions with added salts.Thermodynamic properties,such as activity coefficients of polyelectrolytes or added sa...A molecular thermodynamic model of polyelectrolyte developed previously was extended to polyelectrolyte solutions with added salts.Thermodynamic properties,such as activity coefficients of polyelectrolytes or added salts and osmotic coefficients of solvent, of a number of aqueous mixtures of polyelectrolytes and salts are analyzed with the proposed model.Successful correlation is obtained in the range of moderate or higher polyion concentration.For the same sample,thermodynamic properties of polyelectrolytes with and without simple electrolytes can be predicted mutually using parameters from regression data.展开更多
Nitroguanidine(NQ) isa high energy and low sensitivity explosive and solid-liquid equilibrium data are significant for study on crystallization of NQ. The solubilities of NQ in water, dimethyl sulfoxide, N, N dimeth...Nitroguanidine(NQ) isa high energy and low sensitivity explosive and solid-liquid equilibrium data are significant for study on crystallization of NQ. The solubilities of NQ in water, dimethyl sulfoxide, N, N dimethylformamide, 1,4 butyrolaetone and dimethyl sulfoxide @ water, N, N dimethylformamide + water were measured by dynamic laser monitoring within a temperature range from 298. 15 K to 338. 15 K. The experimental data were correlated by modified Apelblat equation, 2h equation, CNIBS/R K model, andJouyban-Acree model. The results show that the four thermodynamic models can all be used to predict solubility with high accuracy. Accrding to the Akaike's information criterion (AIC), the better models for correlating the solubility of NQ are judged. Additionally, the dissolution enthalpy, entropy and Gibbs free energy were calculated by the van't Hoff equation.展开更多
This study systematically examined the dissolution behavior of furazolidone in 12 different pure solvents and in aqueous solutions containing ethylenediaminetetraacetic acid disodium salt(EDTA-2Na).The solubility data...This study systematically examined the dissolution behavior of furazolidone in 12 different pure solvents and in aqueous solutions containing ethylenediaminetetraacetic acid disodium salt(EDTA-2Na).The solubility data indicated that polar aprotic solvents demonstrated a marginally higher solubility of furazolidone compared to alcohols and water.Interestingly,a co-solvency effect was observed in the aqueous solutions of EDTA-2Na,where the solubility of furazolidone initially increased and then decreased with the gradual addition of EDTA-2Na,peaking at a mass fraction of 0.03(1.949×10^(–5)at 323.15 K).The analysis using the Kamlet-Abboud-Taft Linear Solvation Energy Relationship(KAT-LSER)model suggested that the dissolution of furazolidone in these systems was predominantly influenced by non-specific solute-solvent and solvent-solvent interactions.Furthermore,Hansen solubility parameter calculations revealed that N,N-dimethylformamide(DMF)and N,N-dimethylacetamide(DMAC)exhibited superior dissolution capabilities compared to other solvents.It was also found that the partial solubility parameters played a crucial role in determining the overall solubility behavior.展开更多
基金The National Natural Science Foundation of China (No 50471014)The Science and Technology Foundation of Shanghai (No0210nm017)
文摘A theoretical model on the solvus line prediction of a film was proposed and applied to a nanogranular A1-Cu system. The calculation results show that the solvus line of solute Cu will markedly lower with the decrease of grain size, namely, the starting temperature of θ (Al2Cu) precipitation in a nanogranular A1-Cu film will markedly lower than that of conventional coarse grain alloy with the same Cu concentration, and the precipitation temperatures calculated are comparable with the experimental ones. The theoretical model can be simply used to calculate the starting temperature of precipitation in A1-Cu films under three states: ① films with substrate; ②films without substrate; ③ultrafine grain bulk alloy. As a result, the model is universal, moreover, can be, in principle, used to predict precipitation temperature in other systems.
基金Supported by the National Natural Science Foundation of China (No. 29736170, 29876006).
文摘A molecular thermodynamic model of polyelectrolyte developed previously was extended to polyelectrolyte solutions with added salts.Thermodynamic properties,such as activity coefficients of polyelectrolytes or added salts and osmotic coefficients of solvent, of a number of aqueous mixtures of polyelectrolytes and salts are analyzed with the proposed model.Successful correlation is obtained in the range of moderate or higher polyion concentration.For the same sample,thermodynamic properties of polyelectrolytes with and without simple electrolytes can be predicted mutually using parameters from regression data.
文摘Nitroguanidine(NQ) isa high energy and low sensitivity explosive and solid-liquid equilibrium data are significant for study on crystallization of NQ. The solubilities of NQ in water, dimethyl sulfoxide, N, N dimethylformamide, 1,4 butyrolaetone and dimethyl sulfoxide @ water, N, N dimethylformamide + water were measured by dynamic laser monitoring within a temperature range from 298. 15 K to 338. 15 K. The experimental data were correlated by modified Apelblat equation, 2h equation, CNIBS/R K model, andJouyban-Acree model. The results show that the four thermodynamic models can all be used to predict solubility with high accuracy. Accrding to the Akaike's information criterion (AIC), the better models for correlating the solubility of NQ are judged. Additionally, the dissolution enthalpy, entropy and Gibbs free energy were calculated by the van't Hoff equation.
基金Innovation and Entrepreneurship Training Program for College Students in Shanxi Province (Grant No. 2021100)。
文摘This study systematically examined the dissolution behavior of furazolidone in 12 different pure solvents and in aqueous solutions containing ethylenediaminetetraacetic acid disodium salt(EDTA-2Na).The solubility data indicated that polar aprotic solvents demonstrated a marginally higher solubility of furazolidone compared to alcohols and water.Interestingly,a co-solvency effect was observed in the aqueous solutions of EDTA-2Na,where the solubility of furazolidone initially increased and then decreased with the gradual addition of EDTA-2Na,peaking at a mass fraction of 0.03(1.949×10^(–5)at 323.15 K).The analysis using the Kamlet-Abboud-Taft Linear Solvation Energy Relationship(KAT-LSER)model suggested that the dissolution of furazolidone in these systems was predominantly influenced by non-specific solute-solvent and solvent-solvent interactions.Furthermore,Hansen solubility parameter calculations revealed that N,N-dimethylformamide(DMF)and N,N-dimethylacetamide(DMAC)exhibited superior dissolution capabilities compared to other solvents.It was also found that the partial solubility parameters played a crucial role in determining the overall solubility behavior.