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Titan, the largest satellite of Saturn, has an atmosphere chiefly made up of N(2) and CH(4) and includes traces of many simple organic compounds. This atmosphere also partly consists of haze and aerosol particles which during the last 4.5 gigayears have been processed by electric discharges, ions, and ionizing photons, being slowly deposited over the Titan surface. In this work, we investigate the possible effects produced by soft X-rays (and secondary electrons) on Titan aerosol analogs in an attempt to simulate some prebiotic photochemistry. The experiments have been performed inside a high vacuum chamber coupled to the soft X-ray spectroscopy beamline at the Brazilian Synchrotron Light Source, Campinas, Brazil. In-situ sample analyses were performed by a Fourier transform infrared spectrometer. The infrared spectra have presented several organic molecules, including nitriles and aromatic CN compounds. After the irradiation, the brownish-orange organic residue (tholin) was analyzed ex-situ by gas chromatographic (GC/MS) and nuclear magnetic resonance ((1)H NMR) techniques, revealing the presence of adenine (C(5)H(5)N(5)), one of the constituents of the DNA molecule. This confirms previous results which showed that the organic chemistry on the Titan surface can be very complex and extremely rich in prebiotic compounds. Molecules like these on the early Earth have found a place to allow life (as we know) to flourish.

The essential oil (EO) composition of ripe fruit of S. terebinthifolius Raddi was analyzed by GC-MS. The oil extraction yielded 6.54 ± 1.06% (w/w). Seventeen compounds were identified, accounting for 91.15% of the total oil, where monoterpenes constituted the main chemical class (85.81%), followed by sesquiterpenes (5.34%). The major monoterpene identified was δ-3-carene (30.37%), followed by limonene (17.44%), α-phellandrene (12.60%) and α-pinene (12.59%). Trans-caryophyllene (1.77%) was the major sesquiterpene identified. The antibacterial activity of the essential oil was evaluated against wild strains of hospital origin (Escherichia coli, Pseudomonas sp., Klebsiella oxytoca, Corynebacterium sp., Staphylococcus aureus, Enterobacter sp., Enterobacter agglomerans, Bacillus sp., Nocardia sp. and Streptococcus group D). The essential oil of the ripe fruit of S. terebinthifolius Raddi has shown to be active against all tested wild strains, with minimum inhibitory concentration ranging from 3.55 μg/mL to 56.86 μg/mL. However, it has revealed some differences in susceptibility: the general, Gram-positive species showed greater sensitivity to the action of EO, which is probably due to the lower structural complexity of their cell walls.

The application of ambient ionization mass spectrometry such as paper spray ionisation (PSI) is a fast, powerful, and simple method to analyze designer drugs directly on the surface of blotters. PSI-MS does not require nebulizing gas and heating temperature as well as complex protocols for sample preparation.Herein, it was possible to identify and elucidate the chemical structure of designer drugs using tandem mass spectrometry experiments from a triangular blotter. Substances such as lysergic acid diethylamide (LSD), and five new designer drugs (2,5-dimethoxy-4-chloroamphetamine (DOC), 2,5-dimethoxy-4bromoamphetamine (DOB), 25C-NBOMe, 25B-NBOMe, and 25I-NBOMe) were characterized by PSI-MS. The PSI(+)-MS and PSI(+)-MS/MS data confirmed the assignments of the designer drugs and fragmentation mechanisms have been proposed. From losses of 17 Da (NH 3 ), which is typical of primary amines, the CID results suggest the presence of isomers in the chemical composition of the NBOMe class. Additionally, the data were compared to those of ultra-high-resolution mass spectroscopy (positive-ion electrospray ionization coupled with Fourier transform ion cyclotron mass spectrometry, ESI(+)FT-ICR MS).

Naphthenic acids (NAs), present in a typical Brazilian acid crude oil and its thermal degradation products, were investigated using two separation methodologies: solid-phase extraction (SPE) and liquid–liquid extraction (LLE). Fractions produced were characterized by proton nuclear magnetic resonance spectroscopy (1H NMR) and negative-ion-mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI(−)-FT-ICR MS). Of the NAs extraction methods studied, SPE was more efficient than LLE. Further, ESI(−)-FT-ICR MS results showed that the SPE method with eluent phase variation allowed for the detection of a larger amplitude of NAs compounds (m/z 200–1200), reducing the occurrence of ion suppression on the NAs of higher average molecular weight (M w) distribution. It was noted that the aromaticity or double bond equivalent (DBE) of these produced collective fractions as well as their M w values increased as a function of the polarity of the extraction system (DCM → DCM:MeOH:FA). Also, 1H NMR analysis revealed the alkyl predominance evidenced by the presence of high Hβ content in fractions, suggesting that the NAs compounds have long and unbranched chains. The behavior of NAs species during the thermal degradation process was also evaluated, and the results showed their presence in only five SPE extracts out of six, containing different M w values (M w = 366, 417, 531, 662, and 836 Da). This suggests that, in the last SPE fraction (named SF6: m/z 700–1150, carbon number of C52–C72, and DBE = 0–15; detected only in virgin crude oil), the NAs were selectively cracked during the thermal degradation process.

The contents of saturates, aromatics, and polars in crude oil were determined using carbon-13 nuclear magnetic resonance spectroscopy ( 13 C NMR) associated with support vector regression (SVR) and a genetic algorithm (GA) for the simultaneous selection of spectral variables and SVR model parameters. The developed models presented prediction sample errors of 4.4% (w/w) for saturates, 4.3% (w/w) for aromatics (w/w), and 3.7% (w/w) for polars. These results are acceptable for the petroleum industry, considering that the error obtained by the standard methodology is 5% (w/w), which is the maximum value of variation allowed in SARA analysis. The proposed methodology made these determinations using small amounts of samples (approximately 2 mL) in a relatively short time (approximately 2 h).

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