Solvation of 1-butyl-3-methylimidazolium hexafluorophosphate in aqueous ethanol - a green solution for dissolving 'hydrophobic' ionic liquids

The relatively hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate has been found to be totally miscible with aqueous ethanol between 0.5 and 0.9 mol fraction ethanol, whereas the ionic liquid is only partially miscible with either pure water or absolute ethanol; the ability to dissolve 1-butyl-3-methylimidazolium hexafluorophosphate in a 'green' aqueous solvent system has important implications for cleaning, purification, and separations using ionic liquids.

On the solubilization of water with ethanol in hydrophobic hexafluorophosphate ionic liquids

The solubility of water in the hydrophobic 1-alkyl-3-methylimidazolium hexafluorophosphate (alkyl = butyl, hexyl, and octyl) ionic liquids, can be significantly increased in the presence of ethanol as a co-solute. 1-Hexyl-3-methylimidazolium hexafluorophosphate and 1-octyl-3-methylimidazolium hexafluorophosphate are completely miscible with ethanol, and immiscible with water, whereas 1-butyl-3-methylimidazolium hexafluorophosphate is totally miscible with aqueous ethanol only between 0.5-0.9 mole fraction ethanol at 25degreesC. At higher and lower mole fraction of ethanol, the aqueous and IL components are only partially miscible and a biphasic system is obtained upon mixing equal volumes of the IL and aqueous ethanol. The observation of a large range of total miscibility between water and the IL in the three-component system has important implications for purifications and separations from IL.

Origin of Low CO2 Selectivity on Platinum in the Direct Ethanol Fuel Cell

Calculated answer: First-principles calculations have been applied to calculate the energy barrier for the key step in CO formation on a Pt surface (see picture; Pt blue, Pt atoms on step edge yellow) to understand the low CO2 selectivity in the direct ethanol fuel cell. The presence of surface oxidant species such as O (brown bar) and OH (red bar) led to an increase of the energy barrier and thus an inhibition of the key step. © 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

School-related predictors of smoking, drinking and drug use: Evidence from the Belfast Youth Development Study

Objective

To examine whether students’ school engagement, relationships with teachers, educational aspirations and involvement in fights at school are associated with various measures of subsequent substance use.
Methods

Data were drawn from the Belfast Youth Development Study (n = 2968). Multivariate logistic models examined associations between school-related factors (age 13/14) and substance use (age 15/16).
Results

The two factors which were consistently and independently associated with regular substance use among both males and females were student–teacher relationships and fighting at school: positive teacher-relationships reduced the risk of daily smoking by 48%, weekly drunkenness by 25%, and weekly cannabis use by 52%; being in a fight increased the risk of daily smoking by 54%, weekly drunkenness by 31%, and weekly cannabis use by 43%. School disengagement increased the likelihood of smoking and cannabis use among females only.
Conclusion

Further research should focus on public health interventions promoting positive relationships and safety at school.