12 research outputs found
Viscosity and viscometric properties of glycine in aqueous solutions of sodium thiosulfate pentahydrate (na2s2o3 .5h2o) at different temperatures
Flowing times of Glycine in aqueous solutions Sodium Thiosulfate Pentahydrate (0.01-2.0 mol kg-1) using an AMVn Anton Paar viscometer at temperatures of (283.15; 288.15; 293.15; 298.15; 303.15; 308.15, 313.15 and 318.15) K and 101.1 Kpa.From the data obtained, the absolute viscosity, viscosity B-coefficients, slope (dB/dT),the ΔBtr,adjustable parameters of the equation of Out and Los (BE, BS, K), activation parameters of viscous flow (ΔG°≠, ΔH°≠, ΔS°≠) were calculated , the values obtained for these parameters were discussed in terms of the interactions present in solution
Densidades y propiedades volumétricas de la mezcla n,n-dimetilformamida (dmf) + 1-butanol a diferentes temperaturas
Densities of binary mixture of N, N-dimethylformamide (DMF) + 1-Butanol were determined using a vibrating-tube densimeter DMA 5000, over the entire range of molar fractions in the range temperatures from 283.15 K to 313.15 K and 1.011 bar. Excess molar volumes (), partial molar volumes (), partial molar volumes at infinite dilution (), excess partial molar volumes () of the solute and solvent were calculated. The excess molar volumes were correlated using the Redlich-Kister equation. Additionally, the virial coefficients (bv) were calculated according to the McMillan-Mayer theory. The values obtained for these parameters were discussed in terms of the interactions present in solutionSe determinaron las densidades de la mezcla binaria de N,N-Dimetilformamida (DMF) + 1-Butanol usando un densímetro de tubo vibrador DMA 5000, sobre todo el intervalo de fracciones molares en el intervalo de temperaturas de 283.15K a 313.15K y 1.011 bar. Se calcularon los volúmenes molares de exceso (V), volúmenes molares parciales (), volúmenes molares parciales a dilución infinita (), volúmenes molares parciales de exceso () del soluto y del solvente. Los volúmenes molares de exceso se correlacionaron usando la ecuación de Redlich-Kister. Adicionalmente, se calcularon los coeficientes viriales (bv) de acuerdo a la teoría de McMillan-Mayer. Los valores obtenidos para estos parámetros fueron discutidos en términos de las interacciones presentes en solució
Densidades y propiedades volumétricas de la mezcla n,n-dimetilformamida (dmf) + 1-butanol a diferentes temperaturas
Se determinaron las densidades de la mezcla binaria de N,N-Dimetilformamida (DMF) + 1-Butanol usando un densímetro de tubo vibrador DMA 5000, sobre todo el intervalo de fracciones molares en el intervalo de temperaturas de 283.15K a 313.15K y 1.011 bar. Se calcularon los volúmenes molares de exceso (VmE), volúmenes molares parciales (Vi), volúmenes molares parciales a dilución infinita (Vi∞), volúmenes molares parciales de exceso (ViE) del soluto y del solvente. Los volúmenes molares de exceso se correlacionaron usando la ecuación de Redlich-Kister. Adicionalmente, se calcularon los coeficientes viriales (bv) de acuerdo a la teoría de McMillan-Mayer. Los valores obtenidos para estos parámetros fueron discutidos en términos de las interacciones presentes en solución
Removal of Dyes by Polymer-Enhanced Ultrafiltration: An Overview
The current problem of contamination caused by colored industrial effluents has led to the development of different techniques to remove these species from water. One of them, polymer-enhanced ultrafiltration (PEUF), has been systematically studied in this mini review, in which research works from 1971 to date were found and analyzed. Dye retention rates of up to 99% were obtained in several cases. In addition, a brief discussion of different parameters, such as pH, interfering salts, type of polymer, dye concentration, and membrane type, and their influence in dye removal is presented. It was concluded from the above that these factors can be adapted depending on the pollutant to be remediated, in order to optimize the process. Finally, theoretical approaches have been used to understand the intermolecular interactions, and development of the studied technique. In this revision, it is possible to observe that molecular docking, molecular dynamics simulations, density functional theory calculations, and hybrid neural-genetic algorithms based on an evolutionary approach are the most usual approximations used for this purpose. Herein, there is a detailed discussion about what was carried out in order to contribute to the research development of this important science field
Catalytic activity of a new Ru(ii) complex for the hydrogen transfer reaction of acetophenone and: N -benzylideneaniline: Synthesis, characterization and relativistic DFT approaches
The synthesis and characterization of a new ruthenium(ii) complex containing a hemilabile P^N-ligand are reported. The catalytic activity of this complex was evaluated in the hydrogen transfer reaction of acetophenone and N-benzylideneaniline achieving conversions around 35 and 96% respectively. Condensed Fukui functions in a relativistic DFT scheme show that the regions for the electrophilic (f-) and nucleophilic (f+) attack are Cl- in the axial position, regions belonging to the P^N ligand and the metal center. The lability of the ligands is determined using different theoretical approaches like Morokuma-Ziegler energy decomposition analysis combined with the Extended Transition State with Natural Orbitals of Chemical Valence (ETS-NOCV). The major lability for the -Cl ligand (protic environment) is ideal for designing a new ruthenium hydride complex, suitable for catalytic applications. The σ-donation determines the degree of covalence of the chemical bond involving a lower trend to dissociate, as is the case of the P^N-ligand. The most important excitation energies appear in the region between 250 and 410 nm and are assigned to ligand to ligand charge transfer (LLCT) and metal to ligand charge transfer (MLCT) transitions
Screening of the antileishmanial and antiplasmodial potential of synthetic 2-arylquinoline analogs
Abstract In this study, six analogs of 2-arylquinoline were synthesized and evaluated for their in vitro and in vivo antiplasmodial and leishmanicidal activity. At a later stage, hemolytic activity and druggability were tested in vitro and in silico, respectively, observing as a result: firstly, compounds showed half-maximal effective concentration (EC50) values between 3.6 and 19.3 µM. Likewise, a treatment using the compounds 4a–f caused improvement in most of the treated hamsters and cured some of them. Regarding the antiplasmodial activity, the compounds showed moderate to high activity, although they did not show hemolytic activity. Furthermore, 4e and 4f compounds were not able to control P. berghei infection when administered to animal models. Molecular dynamic simulations, molecular docking and ligand binding affinity indicate good characteristics of the studied compounds, which are expected to be active. And lastly, the compounds are absorbable at the hematoencephalic barrier but not in the gastrointestinal tract. In summary, ADMET properties suggest that these molecules may be used as a safe treatment against Leishmania
The origin of phosphorescence in Iridium (III) complexes. The role of relativistic effects
Structural Characterization, DFT Calculation, NCI, Scan-Rate Analysis and Antifungal Activity against Botrytis cinerea of (E)-2-{[(2-Aminopyridin-2-yl)imino]-methyl}-4,6-di-tert-butylphenol (Pyridine Schiff Base)
Botrytis cinerea is a ubiquitous necrotrophic filamentous fungal phytopathogen that lacks host specificity and can affect more than 1000 different plant species. In this work, we explored L1 [(E)-2-{[(2-aminopyridin-2-yl)imino]-methyl}-4,6-di-tert-butylphenol], a pyridine Schiff base harboring an intramolecular bond (IHB), regarding their antifungal activity against Botrytis cinerea. Moreover, we present a full characterization of the L1 by NMR and powder diffraction, as well as UV–vis, in the presence of previously untested different organic solvents. Complementary time-dependent density functional theory (TD-DFT) calculations were performed, and the noncovalent interaction (NCI) index was determined. Moreover, we obtained a scan-rate study on cyclic voltammetry of L1. Finally, we tested the antifungal activity of L1 against two strains of Botrytis cinerea (B05.10, a standard laboratory strain; and A1, a wild type strains isolated from Chilean blueberries). We found that L1 acts as an efficient antifungal agent against Botrytis cinerea at 26 °C, even better than the commercial antifungal agent fenhexamid. Although the antifungal activity was also observed at 4 °C, the effect was less pronounced. These results show the high versatility of this kind of pyridine Schiff bases in biological applications