The theoretical simulation and verified experiments on metal separation in a Sb^3+-OH^--Cl^-complexation-precipitation system involving hydrolysis-precipitation reactions of SbOCl, Sb4O5Cl2and Sb2O3were carried out. ...The theoretical simulation and verified experiments on metal separation in a Sb^3+-OH^--Cl^-complexation-precipitation system involving hydrolysis-precipitation reactions of SbOCl, Sb4O5Cl2and Sb2O3were carried out. The equilibrium concentration of [Sb^3+]Twas obtained by calculation and verified by experiments. The precipitates SbOCl,Sb4O5Cl2and Sb2O3were analyzed through the equilibrium concentration of Sb^3+in the solution and the ΔrGΘmof transformation reactions of these materials. It is found that the concentration of [Sb^3+]Tin verified experiments was larger than the theoretical value, where the theoretical minimum concentration of [Sb^3+]Twas 10^-10.92mol/L at pH value of 4.6 and the minimum concentration obtained from the verified experiment was about 10^-3.8mol/L at pH value of 5.1. Different precipitates can be obtained atcertain pH. The SbOCl cannot be obtained both in theoretic calculations and in verified experiments, while the Sb8O11Cl2-H2O was generated in the experiment.展开更多
Microstructure and phase transformation of disodium guanosine 5′-monophosphate(5′-GMPNa_2) are extremely important for controlling the process and understanding the mechanism of crystallization. In this work, the th...Microstructure and phase transformation of disodium guanosine 5′-monophosphate(5′-GMPNa_2) are extremely important for controlling the process and understanding the mechanism of crystallization. In this work, the thermodynamic properties of polymorphous 5′-GMPNa_2 especially the solubility were studied, the solubility results show that 5′-GMPNa_2 is more soluble in ethanol–water(E–W) than in isopropanol–water(I–W). The amorphous form of 5′-GMPNa_2 is more soluble than the crystalline form at the same mole fraction and temperature. Meanwhile, the crystalline forms and morphologies of the residual solids were characterized by PXRD and SEM. The results indicate that solid forms of 5′-GMPNa_2 transformed spontaneously from amorphous to crystalline when the ethanol proportion is ≥20%. In addition, increasing the pH facilitates the dissolution of 5′-GMPNa_2 and helps to maintain the crystalline form. The associated Gibbs free energy values were calculated to verify the trend of transformation from amorphous to crystalline 5′-GMPNa_2. These results should help to guide the industrial crystallization process and to obtain the crystalline form of 5′-GMPNa_2.展开更多
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
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 Foun⁃dation of China(No.22005206,22075318)Science and Technolo⁃gy Department of Sichuan Province(No.2022NSFSC1209,2022NS⁃FSC0219)Undergraduate Training Programs for Innovation and Entrepreneurship(No.cx2022046)。
基金Project(51474257)supported by the National Natural Science Foundation of China
文摘The theoretical simulation and verified experiments on metal separation in a Sb^3+-OH^--Cl^-complexation-precipitation system involving hydrolysis-precipitation reactions of SbOCl, Sb4O5Cl2and Sb2O3were carried out. The equilibrium concentration of [Sb^3+]Twas obtained by calculation and verified by experiments. The precipitates SbOCl,Sb4O5Cl2and Sb2O3were analyzed through the equilibrium concentration of Sb^3+in the solution and the ΔrGΘmof transformation reactions of these materials. It is found that the concentration of [Sb^3+]Tin verified experiments was larger than the theoretical value, where the theoretical minimum concentration of [Sb^3+]Twas 10^-10.92mol/L at pH value of 4.6 and the minimum concentration obtained from the verified experiment was about 10^-3.8mol/L at pH value of 5.1. Different precipitates can be obtained atcertain pH. The SbOCl cannot be obtained both in theoretic calculations and in verified experiments, while the Sb8O11Cl2-H2O was generated in the experiment.
基金Supported by the Program for Changjiang Scholars and Innovative Research Team in University(IRT_14R28)the National Basic Research Program of China(2013CB733602)+4 种基金the Major Research Plan of the National Natural Science Foundation of China(21390204)the National Natural Science Foundation of China(21636003,21506090)Open Fund by Jiangsu Key Lab of Biomass-based Green Fuels and Chemicals(JSBGFC14005)Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Microstructure and phase transformation of disodium guanosine 5′-monophosphate(5′-GMPNa_2) are extremely important for controlling the process and understanding the mechanism of crystallization. In this work, the thermodynamic properties of polymorphous 5′-GMPNa_2 especially the solubility were studied, the solubility results show that 5′-GMPNa_2 is more soluble in ethanol–water(E–W) than in isopropanol–water(I–W). The amorphous form of 5′-GMPNa_2 is more soluble than the crystalline form at the same mole fraction and temperature. Meanwhile, the crystalline forms and morphologies of the residual solids were characterized by PXRD and SEM. The results indicate that solid forms of 5′-GMPNa_2 transformed spontaneously from amorphous to crystalline when the ethanol proportion is ≥20%. In addition, increasing the pH facilitates the dissolution of 5′-GMPNa_2 and helps to maintain the crystalline form. The associated Gibbs free energy values were calculated to verify the trend of transformation from amorphous to crystalline 5′-GMPNa_2. These results should help to guide the industrial crystallization process and to obtain the crystalline form of 5′-GMPNa_2.
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.
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.