Complex systems based on nanomaterials and common solvents have been shown to have thermophysical properties that can revolutionize current utilization of heat transfer fluids and heat storage cycles. This has been made possible by the existence of thermal conductivity enhancements derived from the presence of additional mechanisms of heat transfer in comparison with the base solvent. Ionic liquids have been shown to have thermophysical properties that justify the replacement of several of the chemical processes now under exploitation, and some of the solvents used, because they can in certain conditions, be considered as green solvents. Dissolving (or mixing as a thermally stable suspension) nanoparticles in ionic liquids, forms “bucky gels”, or IoNanoFluids, which we have recently shown to have thermal conductivity enhancements ranging from (5 to 35) %. This paper reports data on the thermal conductivity of the ionic liquids 1-hexyl-3-methylimidazolium tetrafluoroborate (CAS Number, 244193-50-8), [C6mim][BF4], 1-butyl-3-methylimidazolium hexafluorophosphate (CAS Number, 174501-64-5), [C4mim][PF6], 1-hexyl-3-methylimidazolium hexafluorophosphate (CAS Number, 304680-35-1), [C6mim][PF6], 1-butyl-3-methylimidazolium trifluoromethanesulfonate (CAS Number, 174899-66-2), [C4mim][CF3SO3], and 1-butyl-1-methylpyrrolidinium bis{(trifluoromethyl)sulfonyl}imide (CAS Number, 223437-11-4), [C4mpyrr][(CF3SO2)2N], and IoNanofluids with multiwalled carbon nanotubes (MWCNTs) as a function of temperature and discuss the molecular theories of heat transfer and storage in these types of systems. Moderate thermal conductivity enhancements, between (2 and 9) %, were found for the systems studied, showing a week dependence on temperature. It also reports heat capacity values for [C4mim][BF4] and [C4mim][PF6]. Values of the heat capacity of an IoNanofluid, C4mim][PF6] with (1 and 1.5) % Baytubes, are reported for the first time, showing also an enhancement (8 %), a fact that deserves further investigation in a near future. The behavior of these nanofluids, along with that of ionic liquids of the type studied, suggests that nanocluster formation and preferred paths for heat transfer and storage are present and are likely to be the cause of the phenomena found. However, existing theories cannot yet explain the results obtained.

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Tagetes erecta L. has long been consumed for culinary and medicinal purposes in different countries. The aim of this study was to explore the potential benefits from two cultivars of T. erecta related to its polyphenolic profile as well as antioxidant and anti-aging properties. The phenolic composition was analyzed by LC-DAD-ESI/MSn. Folin-Ciocalteu, DPPH·, and FRAP assays were performed in order to evaluate reducing antiradical properties. The neuroprotective potential was evaluated using the enzymes acetylcholinesterase and monoamine oxidase. Caenorhabditis elegans was used as an in vivo model to assess extract toxicity, antioxidant activity, delayed aging, and reduced β-amyloid toxicity. Both extracts showed similar phenolic profiles and bioactivities. The main polyphenols found were laricitin and its glycosides. No acute toxicity was detected for extracts in the C. elegans model. T. erecta flower extracts showed promising antioxidant and neuroprotective properties in the different tested models. Hence, these results may add some information supporting the possibilities of using these plants as functional foods and/or as nutraceutical ingredients.

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Excess enthalpies, densities, and speeds of sound at temperatures of (283.15, 298.15, and 313.15) K are reported for binary mixtures of β-pinene + ethanol and β-pinene + 1-propanol. Excess molar volumes have been calculated from the densities. The deviations in the speeds of sound have also been estimated. All of the properties have been fitted to Padé approximants. Excess molar enthalpies and excess molar volumes are positive for both mixtures, whereas the speed of sound deviations show negative values. The values of these properties are discussed in terms of the molecular interactions. The enthalpic and volumetric behaviors of the mixtures are compared with those of the mixtures of ethanol or 1-propanol with cyclohexane or methylcyclohexane, which are two simple hydrocarbons whose basic ring is similar to that of β-pinene.