Yazar "Martínez, Fleming" seçeneğine göre listele

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    Dissolution thermodynamics and preferential solvation of 2,4-dinitrotoluene in (ethanol + water) mixtures
    (Elsevier B.V., 2021) Akay, Sema; Kayan, Berkant; Martínez, Fleming
    Abstract Author keywords Indexed keywords SciVal Topics Abstract In this research, the equilibrium mole fraction solubility of 2,4-dinitrotoluene (2,4-DNT) in some aqueous-ethanolic mixtures was determined at seven temperatures from (293.15 to 323.15) K. The respective apparent thermodynamic functions (Gibbs energy, enthalpy, and entropy of the dissolution processes) were computed using the van't Hoff and Gibbs equations. The enthalpy-entropy relationship for 2,4-DNT was non-linear in the plot of enthalpy vs. Gibbs energy of solution with negative slope in the composition region 0.00 ? w1 ? 0.40 but positive slope in the region 0.40 ? w1 ? 1.00. Therefore, the driving mechanism for 2,4-DNT transfer processes is the entropy in water-rich mixtures and the enthalpy in ethanol-rich mixtures. In addition, by means of the inverse Kirkwood-Buff integrals is observed that 2,4-DNT is preferentially solvated by water molecules in water-rich mixtures but preferentially solvated by ethanol molecules in the mixtures of 0.23 ? x1 ? 1.00.
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    Solubility and dissolution thermodynamics of 5-fluorouracil in (ethanol + water) mixtures
    (Elsevier B.V., 2021) Akay, Sema; Kayan, Berkant; Jouyban, Abolghasem; Martínez, Fleming
    Equilibrium mole fraction solubility of 5-fluorouracil (5-FU) in 19 aqueous-ethanolic mixtures, as well as in neat water and neat ethanol, was determined at seven temperatures from (293.15 to 323.15) K. 5-FU solubility in these mixtures was adequately correlated with several well-known correlation models. The respective apparent thermodynamic functions (Gibbs energy, enthalpy, and entropy) for the dissolution, mixing and solvation processes were computed using the van't Hoff and Gibbs equations. The enthalpy–entropy relationship for 5-FU was non-linear in the plot of enthalpy vs. Gibbs energy of solution with variant but positive slope in almost all the composition regions. Thus, the driving mechanism for 5-FU transfer processes was the enthalpy. In addition, by means of the inverse Kirkwood-Buff integrals is observed that apparently 5-FU is preferentially solvated by water molecules in water-rich mixtures but preferentially solvated by ethanol molecules in ethanol-rich mixtures.
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    Solubility of fluconazole in (ethanol + water) mixtures: Determination, correlation, dissolution thermodynamics and preferential solvation
    (Elsevier B.V., 2021) Akay, Sema; Kayan, Berkant; Martínez, Fleming
    In this research, the equilibrium mole fraction solubility of fluconazole (FLC) in some aqueous-ethanolic mixtures was determined at seven temperatures from (293.15 to 323.15) K. The respective apparent thermodynamic functions (Gibbs energy, enthalpy, and entropy) for the dissolution, mixing and solvation processes were computed using the van't Hoff and Gibbs equations. The enthalpy–entropy relationship for FLC was non-linear in the plot of enthalpy vs. Gibbs energy of solution with negative slope in the composition regions of 0.00 ? w1 ? 0.40 and 0.70 ? w1 ? 1.00. Thus, the driving mechanism for FLC transfer processes in water-rich mixtures is the entropy. In addition, by means of the inverse Kirkwood-Buff integrals is observed that FLC is preferentially solvated by water molecules in water-rich mixtures but preferentially solvated by ethanol molecules in the mixtures of 0.23 < x1 < 1.00.
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    Solubility of Salicylic Acid in Some (Ethanol + Water) Mixtures at Different Temperatures: Determination, Correlation, Thermodynamics and Preferential Solvation
    (Springer, 2023) Akay, Sema; Kayan, Berkant; Peña, María Ángeles; Jouyban, Abolghasem; Martínez, Fleming
    Equilibrium mole fraction solubility of salicylic acid in nine aqueous-ethanolic mixtures, as well as in neat water and neat ethanol, was determined at seven temperatures from T = (293.15 to 323.15) K. Salicylic acid solubility in these mixtures was adequately correlated with well-known correlation/prediction methods based on Jouyban-Acree model. Apparent thermodynamic quantities, i.e. Gibbs energy, enthalpy, and entropy, for the dissolution and mixing processes, were computed by means of the van’t Hoff and Gibbs equations. The enthalpy–entropy compensation plot of enthalpy vs. Gibbs energy of dissolution was not linear exhibiting positive slopes from neat water to the mixture of w 1 = 0.30 and from the mixture of w 1 = 0.50 to neat ethanol indicating enthalpy-driven drug transfer processes but negative in the interval of 0.30 < w 1 < 0.50 indicating entropy-driven drug transfer processes from more polar to less polar solvent systems. Moreover, by using the inverse Kirkwood–Buff integrals it is observed that salicylic acid is preferentially solvated by water molecules in water-rich mixtures but preferentially solvated by ethanol molecules in those mixtures of 0.24 < x 1 < 1.00.