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Derek G. Leaist - One of the best experts on this subject based on the ideXlab platform.
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ternary Mutual Diffusion in aqueous ethambutol dihydrochloride hydrochloric acid solutions
The Journal of Chemical Thermodynamics, 2015Co-Authors: Luis M.p. Verissimo, Licínia L. G. Justino, Hugh D. Burrows, Ana M. T. D. P. V. Cabral, Derek G. Leaist, Luisa M Ramos, Ana C.f. RibeiroAbstract:Abstract Ternary Mutual Diffusion coefficients measured by the Taylor dispersion method are reported for aqueous solutions of {ethambutol dihydrochloride (1) + HCl (2)} at 25 °C and various carrier solution compositions. Mutual Diffusion coefficients estimated from limiting ionic conductivities using Nernst equations are used to discuss the composition dependence of the measured Diffusion coefficients. 1 H NMR studies, combined with DFT calculations, confirm a fully extended conformation for the diprotonated form of the drug present under these conditions, and are consistent with an electrostatic mechanism for the strongly coupled Diffusion of diprotonated ethambutol and HCl.
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Ternary Mutual Diffusion in aqueous (ethambutol dihydrochloride + hydrochloric acid) solutions
The Journal of Chemical Thermodynamics, 2015Co-Authors: Luis M.p. Verissimo, M. Luísa Ramos, Licínia L. G. Justino, Hugh D. Burrows, Ana M. T. D. P. V. Cabral, Derek G. Leaist, Ana C.f. RibeiroAbstract:Abstract Ternary Mutual Diffusion coefficients measured by the Taylor dispersion method are reported for aqueous solutions of {ethambutol dihydrochloride (1) + HCl (2)} at 25 °C and various carrier solution compositions. Mutual Diffusion coefficients estimated from limiting ionic conductivities using Nernst equations are used to discuss the composition dependence of the measured Diffusion coefficients. 1 H NMR studies, combined with DFT calculations, confirm a fully extended conformation for the diprotonated form of the drug present under these conditions, and are consistent with an electrostatic mechanism for the strongly coupled Diffusion of diprotonated ethambutol and HCl.
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Mutual Diffusion coefficients in systems containing the nickel ion
Comptes Rendus Mécanique, 2013Co-Authors: Ana C.f. Ribeiro, Luis V.m.m. Veríssimo, Joselaine C.s. Gomes, Cecilia I.a.v. Santos, Marisa C.f. Barros, Victor M.m. Lobo, Abilio J.f.n. Sobral, Miguel A. Esteso, Derek G. LeaistAbstract:Abstract Mutual Diffusion coefficients of nickel chloride in water have been measured at 293.15 K and 303.15 K and at concentrations between 0.020 mol dm −3 and 0.100 mol dm −3 , using a conductimetric cell. The experimental Mutual Diffusion coefficients are discussed on the basis of the Onsager–Fuoss model. The equivalent conductances at infinitesimal concentration of the nickel ion in these solutions at those temperatures have been estimated using these results. In addition, from these data, we have estimated some transport and structural parameters, such as limiting Diffusion coefficient, ionic conductance at infinitesimal concentration, hydrodynamic radii and activation energy, contributing this way to a better understanding of the structure of these systems and of their thermodynamic behavior in aqueous solution at different concentrations.
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Ternary Mutual Diffusion Coefficients of Aqueous NiCl2 + NaCl and NiCl2 + HCl Solutions at 298.15 K
Journal of Chemical & Engineering Data, 2011Co-Authors: Ana C.f. Ribeiro, Joselaine C.s. Gomes, Cecilia I.a.v. Santos, Victor M.m. Lobo, Miguel A. Esteso, Derek G. LeaistAbstract:The influence of sodium chloride and hydrochloric acid on the Diffusion of aqueous nickel chloride has been investigated by using Taylor dispersion to measure ternary Mutual Diffusion coefficients for aqueous solutions of NiCl2 + NaCl and NiCl2 + HCl at 298.15 K and carrier concentrations from (0.000 to 0.050) mol·dm–3 for each solute. Mutual Diffusion coefficients estimated from limiting ionic conductivities using Nernst equations are used to discuss the composition dependence of the Diffusion coefficients and the electrostatic mechanism for the strongly coupled Diffusion of the solutes.
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ternary Mutual Diffusion coefficients of aqueous nicl2 nacl and nicl2 hcl solutions at 298 15 k
Journal of Chemical & Engineering Data, 2011Co-Authors: Ana C.f. Ribeiro, Joselaine C.s. Gomes, Cecilia I.a.v. Santos, Victor M.m. Lobo, Miguel A. Esteso, Derek G. LeaistAbstract:The influence of sodium chloride and hydrochloric acid on the Diffusion of aqueous nickel chloride has been investigated by using Taylor dispersion to measure ternary Mutual Diffusion coefficients for aqueous solutions of NiCl2 + NaCl and NiCl2 + HCl at 298.15 K and carrier concentrations from (0.000 to 0.050) mol·dm–3 for each solute. Mutual Diffusion coefficients estimated from limiting ionic conductivities using Nernst equations are used to discuss the composition dependence of the Diffusion coefficients and the electrostatic mechanism for the strongly coupled Diffusion of the solutes.
Ana C.f. Ribeiro - One of the best experts on this subject based on the ideXlab platform.
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ternary Mutual Diffusion in aqueous ethambutol dihydrochloride hydrochloric acid solutions
The Journal of Chemical Thermodynamics, 2015Co-Authors: Luis M.p. Verissimo, Licínia L. G. Justino, Hugh D. Burrows, Ana M. T. D. P. V. Cabral, Derek G. Leaist, Luisa M Ramos, Ana C.f. RibeiroAbstract:Abstract Ternary Mutual Diffusion coefficients measured by the Taylor dispersion method are reported for aqueous solutions of {ethambutol dihydrochloride (1) + HCl (2)} at 25 °C and various carrier solution compositions. Mutual Diffusion coefficients estimated from limiting ionic conductivities using Nernst equations are used to discuss the composition dependence of the measured Diffusion coefficients. 1 H NMR studies, combined with DFT calculations, confirm a fully extended conformation for the diprotonated form of the drug present under these conditions, and are consistent with an electrostatic mechanism for the strongly coupled Diffusion of diprotonated ethambutol and HCl.
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Ternary Mutual Diffusion in aqueous (ethambutol dihydrochloride + hydrochloric acid) solutions
The Journal of Chemical Thermodynamics, 2015Co-Authors: Luis M.p. Verissimo, M. Luísa Ramos, Licínia L. G. Justino, Hugh D. Burrows, Ana M. T. D. P. V. Cabral, Derek G. Leaist, Ana C.f. RibeiroAbstract:Abstract Ternary Mutual Diffusion coefficients measured by the Taylor dispersion method are reported for aqueous solutions of {ethambutol dihydrochloride (1) + HCl (2)} at 25 °C and various carrier solution compositions. Mutual Diffusion coefficients estimated from limiting ionic conductivities using Nernst equations are used to discuss the composition dependence of the measured Diffusion coefficients. 1 H NMR studies, combined with DFT calculations, confirm a fully extended conformation for the diprotonated form of the drug present under these conditions, and are consistent with an electrostatic mechanism for the strongly coupled Diffusion of diprotonated ethambutol and HCl.
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Mutual Diffusion coefficients of l lysine in aqueous solutions
The Journal of Chemical Thermodynamics, 2014Co-Authors: Melia M Rodrigo, Luis M.p. Verissimo, Marisa C.f. Barros, Miguel A. Esteso, Artur J M Valente, Carmen M Romero, Ana C.f. RibeiroAbstract:Abstract Mutual Diffusion coefficients, D, were determined for aqueous solutions of l -lysine at T = 298.15 K at concentrations from (0.001 to 0.100) mol · dm−3. From these experimental results, the hydrodynamic radius Rh, Diffusion coefficients at infinite dilution D0, the thermodynamic factors and activity coefficients γ, by using the Hartley equation, have been estimated, permitting us to have a better understanding of the thermodynamic of these systems of l -lysine in aqueous solutions.
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Mutual Diffusion of sodium hyaluranate in aqueous solutions
The Journal of Chemical Thermodynamics, 2014Co-Authors: Luis M.p. Verissimo, Abilio J.f.n. Sobral, Teresa I.c. Valada, Eduarda F. G. Azevedo, Maria L.g. Azevedo, Ana C.f. RibeiroAbstract:Abstract The Taylor dispersion technique has been used for measuring Mutual Diffusion coefficients of sodium hyaluronate in aqueous solutions at T = 298.15 K, and concentrations ranging from (0.00 to 0.50) g · dm −3 . The results are interpreted on the basis of Nernst, and Onsager and Fuoss theoretical equations. From the Diffusion coefficient at infinitesimal concentration, the limiting ionic conductivity and the tracer Diffusion coefficient of hyaluronate ion were estimated. These studies have been complemented by molecular mechanics calculations.
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Mutual Diffusion coefficients in systems containing the nickel ion
Comptes Rendus Mécanique, 2013Co-Authors: Ana C.f. Ribeiro, Luis V.m.m. Veríssimo, Joselaine C.s. Gomes, Cecilia I.a.v. Santos, Marisa C.f. Barros, Victor M.m. Lobo, Abilio J.f.n. Sobral, Miguel A. Esteso, Derek G. LeaistAbstract:Abstract Mutual Diffusion coefficients of nickel chloride in water have been measured at 293.15 K and 303.15 K and at concentrations between 0.020 mol dm −3 and 0.100 mol dm −3 , using a conductimetric cell. The experimental Mutual Diffusion coefficients are discussed on the basis of the Onsager–Fuoss model. The equivalent conductances at infinitesimal concentration of the nickel ion in these solutions at those temperatures have been estimated using these results. In addition, from these data, we have estimated some transport and structural parameters, such as limiting Diffusion coefficient, ionic conductance at infinitesimal concentration, hydrodynamic radii and activation energy, contributing this way to a better understanding of the structure of these systems and of their thermodynamic behavior in aqueous solution at different concentrations.
Rolando Castillo - One of the best experts on this subject based on the ideXlab platform.
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Mutual Diffusion coefficients of alkaline-earth and third-family metal chlorides in aqueous solutions
International Journal of Thermophysics, 1996Co-Authors: Rolando Castillo, Cristina GarzaAbstract:Measurements of Mutual Diffusion coefficients of several metal chlorides in aqueous solutions close to infinite dilution have been made with the Taylor dispersion technique. Data were obtained for alkaline earth metal chlorides. BeCl2/H2O, MgCl2/H2O, CaCl2/H2O, SrCl2/H2O, and BaCl2/H2O, and for third-family metal chlorides, AlCl2/H2O, and GaCl3/H2O. All the measurements were obtained at five temperatures between 298.15 and 318.15 K. A linear dependence between the Mutual Diffusion coefficient and temperature was found. In the range of temperatures studied here, the values of the Mutual Diffusion coefficients follow a sequence: BaCl2 > SrCl2 > CaCl2 > MgCl2 > BeCl2 for alkaline-earth metal chlorides and GaCl3 > AlCl3, for third-family metal chlorides. That is, the higher the atomic weight of the cation. the higher the Mutual Diffusion coefficient. A comparison of Mutual Diffusion coefficients of alkaline, alkaline earth, and third-family metal chlorides is presented.
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The Mutual Diffusion coefficient for the van der Waals binary mixtures of types II, III, IV, and V
The Journal of Chemical Physics, 1994Co-Authors: Rolando Castillo, Cristina Garza, H. DominguezAbstract:In the framework of the mean‐field kinetic variational theory, a numerical study is presented to understand the concentration dependence of the Mutual Diffusion coefficient in terms of molecular sizes and interaction parameters for the van der Waals binary mixtures of types II, III, IV, and V, in the scheme of Scott and van Konynenburg. This work is an extension to the study for systems of type I presented by us quite recently. In addition, the behavior of the Mutual Diffusion coefficient of the van der Waals mixture is compared with that of the hard‐sphere mixture and for the case of systems of type II, with experimental data of actual systems: water/n‐propanol, n‐hexane/acetone, and n‐heptane/acetone. The Mutual Diffusion coefficients for the last two systems were determined by us with the Taylor dispersion technique. The Mutual Diffusion coefficients for the systems n‐hexane/acetone and n‐heptane/acetone are reported here at 298.15 and 303.15 K, respectively, along all the concentration range. The expl...
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The Mutual Diffusion coefficient for the van der Waals binary mixture of type I
The Journal of Chemical Physics, 1993Co-Authors: Rolando Castillo, Cristina Garza, H. DominguezAbstract:In the framework of the mean‐field kinetic variational theory, the explicit dependence of the Mutual Diffusion coefficient of the van der Waals binary mixture with composition and interaction parameters is obtained. The different kinds of behavior shown by this coefficient can be classified according to the scheme of van Konynenburg and Scott devised to describe the global phase diagram of this model mixture. A numerical study to understand the concentration dependence of the Mutual Diffusion coefficients for mixtures of type I is presented here, in terms of molecular masses, sizes, and interaction parameters. Moreover, the behavior of the Mutual Diffusion coefficient of the van der Waals mixture is compared with that of a hard‐sphere mixture. In addition, a comparison is made between our calculations and experimental data of binary systems classified as belonging to type I: H2O/D2O, hexane/heptane, toluene/hexane, and benzene/hexane. From the explicit model presented here, one can obtain semiquantitative...
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Determination of Mutual Diffusion coefficients in water-rich 2-butoxyethanol/water mixtures using the Taylor dispersion technique
The Journal of Physical Chemistry, 1990Co-Authors: Rolando Castillo, Hector C. Dominguez, Miguel CostasAbstract:Mutual Diffusion coefficients D 12 of 2-butoxyethanol (2BE)/water mixtures in the water-rich region were determined at 298 K by using the Taylor dispersion technique. In addition, the Mutual Diffusion coefficients at infinite dilution were measured at several temperatures between 293 and 323 K
H. Dominguez - One of the best experts on this subject based on the ideXlab platform.
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The Mutual Diffusion coefficient for the van der Waals binary mixtures of types II, III, IV, and V
The Journal of Chemical Physics, 1994Co-Authors: Rolando Castillo, Cristina Garza, H. DominguezAbstract:In the framework of the mean‐field kinetic variational theory, a numerical study is presented to understand the concentration dependence of the Mutual Diffusion coefficient in terms of molecular sizes and interaction parameters for the van der Waals binary mixtures of types II, III, IV, and V, in the scheme of Scott and van Konynenburg. This work is an extension to the study for systems of type I presented by us quite recently. In addition, the behavior of the Mutual Diffusion coefficient of the van der Waals mixture is compared with that of the hard‐sphere mixture and for the case of systems of type II, with experimental data of actual systems: water/n‐propanol, n‐hexane/acetone, and n‐heptane/acetone. The Mutual Diffusion coefficients for the last two systems were determined by us with the Taylor dispersion technique. The Mutual Diffusion coefficients for the systems n‐hexane/acetone and n‐heptane/acetone are reported here at 298.15 and 303.15 K, respectively, along all the concentration range. The expl...
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The Mutual Diffusion coefficient for the van der Waals binary mixture of type I
The Journal of Chemical Physics, 1993Co-Authors: Rolando Castillo, Cristina Garza, H. DominguezAbstract:In the framework of the mean‐field kinetic variational theory, the explicit dependence of the Mutual Diffusion coefficient of the van der Waals binary mixture with composition and interaction parameters is obtained. The different kinds of behavior shown by this coefficient can be classified according to the scheme of van Konynenburg and Scott devised to describe the global phase diagram of this model mixture. A numerical study to understand the concentration dependence of the Mutual Diffusion coefficients for mixtures of type I is presented here, in terms of molecular masses, sizes, and interaction parameters. Moreover, the behavior of the Mutual Diffusion coefficient of the van der Waals mixture is compared with that of a hard‐sphere mixture. In addition, a comparison is made between our calculations and experimental data of binary systems classified as belonging to type I: H2O/D2O, hexane/heptane, toluene/hexane, and benzene/hexane. From the explicit model presented here, one can obtain semiquantitative...
Luis M.p. Verissimo - One of the best experts on this subject based on the ideXlab platform.
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ternary Mutual Diffusion in aqueous ethambutol dihydrochloride hydrochloric acid solutions
The Journal of Chemical Thermodynamics, 2015Co-Authors: Luis M.p. Verissimo, Licínia L. G. Justino, Hugh D. Burrows, Ana M. T. D. P. V. Cabral, Derek G. Leaist, Luisa M Ramos, Ana C.f. RibeiroAbstract:Abstract Ternary Mutual Diffusion coefficients measured by the Taylor dispersion method are reported for aqueous solutions of {ethambutol dihydrochloride (1) + HCl (2)} at 25 °C and various carrier solution compositions. Mutual Diffusion coefficients estimated from limiting ionic conductivities using Nernst equations are used to discuss the composition dependence of the measured Diffusion coefficients. 1 H NMR studies, combined with DFT calculations, confirm a fully extended conformation for the diprotonated form of the drug present under these conditions, and are consistent with an electrostatic mechanism for the strongly coupled Diffusion of diprotonated ethambutol and HCl.
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Ternary Mutual Diffusion in aqueous (ethambutol dihydrochloride + hydrochloric acid) solutions
The Journal of Chemical Thermodynamics, 2015Co-Authors: Luis M.p. Verissimo, M. Luísa Ramos, Licínia L. G. Justino, Hugh D. Burrows, Ana M. T. D. P. V. Cabral, Derek G. Leaist, Ana C.f. RibeiroAbstract:Abstract Ternary Mutual Diffusion coefficients measured by the Taylor dispersion method are reported for aqueous solutions of {ethambutol dihydrochloride (1) + HCl (2)} at 25 °C and various carrier solution compositions. Mutual Diffusion coefficients estimated from limiting ionic conductivities using Nernst equations are used to discuss the composition dependence of the measured Diffusion coefficients. 1 H NMR studies, combined with DFT calculations, confirm a fully extended conformation for the diprotonated form of the drug present under these conditions, and are consistent with an electrostatic mechanism for the strongly coupled Diffusion of diprotonated ethambutol and HCl.
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Mutual Diffusion coefficients of l lysine in aqueous solutions
The Journal of Chemical Thermodynamics, 2014Co-Authors: Melia M Rodrigo, Luis M.p. Verissimo, Marisa C.f. Barros, Miguel A. Esteso, Artur J M Valente, Carmen M Romero, Ana C.f. RibeiroAbstract:Abstract Mutual Diffusion coefficients, D, were determined for aqueous solutions of l -lysine at T = 298.15 K at concentrations from (0.001 to 0.100) mol · dm−3. From these experimental results, the hydrodynamic radius Rh, Diffusion coefficients at infinite dilution D0, the thermodynamic factors and activity coefficients γ, by using the Hartley equation, have been estimated, permitting us to have a better understanding of the thermodynamic of these systems of l -lysine in aqueous solutions.
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Mutual Diffusion of sodium hyaluranate in aqueous solutions
The Journal of Chemical Thermodynamics, 2014Co-Authors: Luis M.p. Verissimo, Abilio J.f.n. Sobral, Teresa I.c. Valada, Eduarda F. G. Azevedo, Maria L.g. Azevedo, Ana C.f. RibeiroAbstract:Abstract The Taylor dispersion technique has been used for measuring Mutual Diffusion coefficients of sodium hyaluronate in aqueous solutions at T = 298.15 K, and concentrations ranging from (0.00 to 0.50) g · dm −3 . The results are interpreted on the basis of Nernst, and Onsager and Fuoss theoretical equations. From the Diffusion coefficient at infinitesimal concentration, the limiting ionic conductivity and the tracer Diffusion coefficient of hyaluronate ion were estimated. These studies have been complemented by molecular mechanics calculations.
