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Ion beam induced luminescence (IBIL) analysis was performed on organic targets are typical organic contaminants in aerosols. An external proton microbeam with an energy of 3 MeV was selected as the probe for the continuous IBIL measurement. Commercially available organic standards, including common amino acids (nicotinamide adenine dinucleotide, riboflavin and tryptophan) and a polycyclic aromatic hydrocarbon (benzo[a]pyrene), were used to test the analysis. Differences in chemical composition were distinguished by the shape of the IBIL spectrum in the UV/visible/near-IR region (200–900 nm). The IBIL spectrum changed as the proton irradiation damage increased. These results suggest that qualitative characterization of organic materials might be possible through the continuous measurement of IBIL spectra.

The polycyclic aromatic hydrocarbons (PAHs) are chemical compounds of obvious technical and medical interest. In the present work, we analyze the optical and reactive properties of several small (6–50 Carbon atoms) and large (100–5000 Carbon atoms) irregular PAHs. These properties have been calculated by using the (Frozen) spin molecular orbital (SMO) Hartree-Fock (HF) approach, referred to as FHF, because of its high computational efficiency. There is a reasonable agreement of our results with those previously obtained by other authors. The FHF approach is (about 1000 times) faster than the conventional semi-empirical methods, and only requires the chemical formula of the PAH as input.

Layer-by-layer (LbL) self-assembly is one of the unique methods for fabrication of ultra-thin film. This technique has immense application aross many fields in today’s life. In this paper, we have presented the fabrication of the thin film comprising of antifungal and antibacterial cationic dye methylene blue with negatively charged E. coli K30 bacterial polysaccharide sharing with PAH. The multilayers were characterized by UV–Vis absorption spectra and AFM. Various photophysical behaviors were investigated. Such studies provide a new light in the research of layer by layer self-assembly technique.

Arthrobacter sp. STTX12 was found to utilize a wide range of polyaromatic hydrocarbon (PAH) and other hydrocarbons used in the study viz. anthracene, naphthalene, chrysene, benzene, toluene and xylene on MSB as sole carbon and energy source.It also had the plant growth promoting (PGP) attributes like phytohormone (IAA) production, phosphate solubilization, HCN and siderophore production and antagonism against Macrophomina phaseolina and Rhizoctinia solanii with percent inhibition of 46.6% and 52.4% respectively. Also, it was found to have positive chemotactic response for anthracene and naphthalene. Decrease in mean growth rate constant (K) was recorded when PAH was provided as sole source of carbon to Arthrobacter sp. STTX12, with respect to control supplemented with glucose.

The discovery of cross-linked hetero-aromatic polymers in interstellar dust by instruments aboard the Stardust spacecraft would confirm the validity of the biological grain model that was suggested from spectroscopic studies over 20 years ago. Such structures could represent fragments of cell walls that survive 30 km/s impacts onto detector surfaces.

We show that heterocyclic aromatic compounds could explain the interstellar absorption feature at 2200Å, requiring 10% of the available interstellar C and N to be tied up in this form.