Ethyl lactate is a green, and economically viable, alternative to traditional solvents whose extensive use and scale-up to industrial level requires a deep and accurate knowledge of its properties in wide pressure-temperature ranges. In this work, the pressure-volume-temperature and pressure-viscosity-temperature behaviors are reported together with several derived properties of remarkable importance for process design purposes. The structure of the liquid is analyzed at the microscopic level using the Density Functional Theory and from classical molecular dynamics simulations. It is shown the competing effect of intra and intermolecular hydrogen bonding mainly through preferred positions. The predictive ability of the forcefield used for molecular dynamics simulations is studied, showing good results for most of the considered properties. Monte Carlo/Gibbs ensemble simulations were carried out to predict the phase equilibria of the fluid, considering the absence of experimental data.

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A study on the viscosity of eight pyridinium based ionic liquids is reported for wide pressure and temperature ranges. Measurements were performed using an electromagnetic moving piston viscometer. Experimental data were fitted to a Tait-like equation demonstrating good correlations, which was used to calculate pressure/viscosity and temperature/viscosity coefficients. The effect of the involved anions and cation on the ionic liquid viscosity was analyzed from a molecular viewpoint using hole theory, quantum chemistry calculations using density functional theory, and classical molecular dynamics simulations. The analysis of the experimental and computational results shows the complex effects controlling viscosity of studied fluids, including strength of ionic pairs, molecular sizes, and mobility and effects rising from the availability and cavity sizes distributions in pyridinium-based ionic liquids.

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Metallothionein (MT), a low molecular weight metal-binding protein, has been related to zinc and copper metabolism, the acute-phase response, and cellular proliferation. In this study, we investigated changes in zinc metabolism and MT gene expression occurring in tissue damage and repair during wound healing in mouse skin. Northern blot analysis revealed that a significant increase of MT mRNA was observed in the liver for 18 h after wounding, and serum zinc downfall and hepatic zinc uptake were observed. In situ hybridization analysis showed that no significant expression of MT mRNA was detected within the first 9 h after wounding. However, it was expressed restrictively in the proliferating epidermis of the wound margin after 12 h. Zinc began to accumulate in wounded skin after MT gene expressed. Northern blotting and immunocytochemical staining revealed that MT has been synthesized actively during the growth phase compared with the stationary phase in normal human epidermal keratinocytes in vitro. Intracellular zinc accumulation was observed in the proliferating cells. We concluded that hepatic MT plays an important role as an acute phase protein against host damage, and epidermal MT contributes in the supply of zinc to wounded tissue and activates proliferation for the regeneration of epidermis.

Two selected ammonium-based ionic liquids, 2-hydroxyethyltrimethylammonium L-(+)-lactate and tris(2-hydroxyethyl)methylammonium methylsulfate, were fully characterized. The most relevant thermophysical properties of pure fluids were measured and analyzed as a function of temperature. Structural features were inferred from solvatochromic and Fourier transform infrared (FTIR) studies. Moisture absorption ability was also studied by gravimetric, spectroscopic, and Karl Fischer methods. Likewise, the water effect on fluids properties was analyzed. Polarity was studied by approaches based on solvatochromic measurements and on the water effect on FTIR spectra. Moreover, as computational work, quantum chemistry and molecular dynamics simulation methods were used to analyze the main molecular-level structural features in these fluids. The work is divided into two parts; in this first paper, the main objective is fully characterizing these ionic liquids in the pure state, and in the second paper CO(2) absorption will be analyzed, therefore leading to a deep knowledge of factors controlling structuring, properties, and CO(2) absorption for this family of ionic liquids in comparison with available information for other relevant types of ionic liquids.