A thermogravimetric analyzer (TGA) was used to oxidize real diesel soot produced in a modern four-cylinder, turbo-charged, diesel engine equipped with a common rail injection system. In the first part of the study, a large amount of soot produced with a variety of diesel fuels of current and future interest and in typical engine modes was collected. A thorough test matrix was designed and executed in the TGA to develop an optimized oxidation method, which allows for the determination of oxidation profiles, characteristic temperatures, and Arrhenius kinetic parameters. Such parameters are critical for modeling diesel filter regeneration and designing more efficient regeneration techniques. A comparison of this method to others proposed in previous literature is made, and the advantages are pointed out. In the second part, diesel and biodiesel soot produced in three engine operating modes (low, medium, and high load) was evaluated with the proposed method. The results showed that the effect of the fuel on the oxidation process was more significant than that of the engine mode. Biodiesel soot oxidation occurred at lower temperatures, proving the possibilities that this fuel offers for achieving more efficient filter regeneration. Although differences in the activation energy of diesel and biodiesel soot were not large, the oxidation rates of biodiesel soot were, on average, 1 order of magnitude above those of diesel soot.

Hydroxyapatite HAp, Ca10(PO4)6(OH)2, was successfully synthesized using a hydrothermal method using β-tricalcium phosphate (β-TCP) and CaO from the starfish Mellita eduardobarrosoi sp. nov.

A series of 3, 5 and 7 quinoline terminated arylenevinylene oligomers was selectively synthesized by applying two repetitive reactions at each cycle of oligomerization: a Wittig and Pd Heck cross-coupling. Oligomers were characterized by 1 H and homo-J-resolved, DEPT-135, APT, 13 C NMR and MALDI-TOF spectrometry.A detailed characterization of the oligomers was performed by UV-Vis, static-dynamic fluorescence and Z-scan spectroscopy. The HOMO and LUMO levels were determined by cyclic voltammetry and compared with the theoretical ones. Effective conjugation is attained for the pentamer, whilst the molecular structure of the heptamer shows a pronounced torsion of the phenylenevinylene segment disrupting the degree of conjugation as revealed by theoretical simulation of the oligomer geometry. Furthermore, the theoretical simulation shows that the HOMO-LUMO frontier orbitals are mainly localized in the phenylenevinylene structure, while in the quinolines the spatial distribution is only located at the CQN-group without any appreciable contribution of the adjacent phenyl group. The pentamer is the most fluorescent oligomer with a quantum yield in solution of f = 0.62-0.68 depending on the solvent and a fluorescence lifetime of 1.07-1.28 ns, making this oligomer suitable for optoelectronic devices.

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