Two triarylamine centers bridged through an aliphatic bridge feature unexpected charge transfer properties, bearing an important electronic coupling between them in the absence of a π linker; EPR, electrochemistry, electronic spectroscopy and first principles molecular calculations are combined to study the electronic structure of this compound.

A retrospective analysis of a comprehensive series of high-volume air samples (n = 70) collected during 2010−2011 in Toronto (Canada) was performed. Seven UV compounds were analyzed by gas chromatography−tandem mass spectrometry (GC−MS/MS) with sum of concentrations (gas + particle phase) ranging from 80 to 2030 pg/m 3 . Homosalate (HMS) was the most prevalent organic UV-filter in air (47% of the total concentration), followed by 2-ethylhexyl salicylate (EHS, ∼29%), E-and Z-2-ethylhexyl 4-methoxycinnamate (EHMC, ∼17%). Ambient air (gas + particle phase) concentrations of organic UVfilters showed a strong seasonality, with peak levels during the summer. An analysis of Clausius−Clapeyron slopes indicated that much of the ambient burden of organic UV-filters are explained by volatilization from terrestrial and aquatic surfaces and supplemented with human activities and use of lotions and sunscreens, containing organic UV-filters, in addition to its use in plastics, textiles, paints, and pesticides. The results showed that organic UVfilters exist mainly in the gas phase with some exceptions, for instance, octocrylene (OCR), which was associated with both gas and particle phases, and avobenzone (AVB), which was predominantly in the particle phase. Lastly, this study revealed the need for basic physical chemical property data for organic UV-filters, including information on transformation rates and products, for better evaluating their environmental fate and effects.

The present study shows the variability in chemical profiles of three different varieties of Cannabis sativa extracts used in medicinal cannabis oil when using two different extraction and evaporation methods. Procedures were compared by analyzing rate of total terpenoids to the principal cannabinoids, tetrahydrocannabinol (THC) and cannabidiol (CBD), using gas chromatography coupled to mass spectrometry (GC-MS). The extraction of inflorescences using soxhlet method showed the highest mass of final extract. Also, the use of heating and the presence of oxygen when evaporating the solvents, greatly modified the final profiles due to evaporation or chemical reactions. These variations in chemical profiles must be carefully taken into account and standardized in the elaboration of medicinal oils.