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The post-compression technique based on self-phase modulation of high-energy pulses leads to an increase in achievable peak power and intensity. Typically, the pulses considered in experiments have been less than 100 fs in duration. Here, the method is applied to the ELFIE laser system at the LULI facility, for a pulse of 7 J energy and an initial measured duration of 350 fs. A 5-mm-thick fused silica window and a 2 mm cyclic-olefin polymer were used as optical nonlinear materials. The 9 cm diameter beam was spectrally broadened to a bandwidth corresponding to 124 fs Fourier-limited pulse duration, and then it was partly post-compressed to 200 fs. After measuring the spatial spectra of the beam fluence, a uniform gain factor of 4 increase in the fluctuations over the studied range of frequencies is observed, due to small-scale self-focusing. [ABSTRACT FROM AUTHOR]

Increasing environmental problems related to synthetic plastics for food packaging encourage the creation of more environmentally friendly plastics from Indonesia’s local natural resources, such as durian seed, yellow konjac, and Syzygium myrtifolium leaves, which are abundant in nature. The purpose of the study was to evaluate the effect of the durian seed flour (DSF) mass, yellow konjac flour (YKF) mass, and the concentration of ethanolic extract of S. myrtifolium leaves (5-25%) on the tensile strength, elongation, and inhibition zone area of composite bioplastics. The two-level full factorial design was conducted for this experiment with 3 independent factors: DSF mass (0.5-1 g), YKF mass (0.5-1 g), and the concentration of ethanolic extract of S. myrtifolium leaves (5-25% b/v), and 3 responses were observed: tensile strength, elongation, and inhibition zone area. The physicomechanical characteristics were then used to further describe the best combination. The results showed that the DSF mass had only affected tensile strength, whereas the YKF mass had affected tensile strength and elongation of composite bioplastics. Meanwhile, the concentration of ethanolic extract of S. myrtifolium leaves only affects the inhibition zone area. The best combination was found in the DSF mass of 0.5 g, YKF mass of 1 g, and the concentration of ethanolic extract of S. myrtifolium leaves of 25%, with the tensile strength of 3.30 MPa, elongation of 50.00%, and inhibition zone area of 15.33 mm. Moreover, these combinations also had a thickness of 0.115 mm, modulus young of 0.066 MPa, density of 1.37 g.cm-3, moisture content of 17.14%, and water solubility of 76.91%. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) is applied in fuel processing technology to convert bio-oils to green diesel with metalbased catalysts. The major challenges to this process are feedstock, catalyst preparation, and the production of oxygen-free diesel fuel. In this study, we aimed to synthesize Ni catalysts supported on silica-zirconia and aluminazirconia binary oxides and evaluated their catalytic activity for waste cooking oil (WCO) hydrodeoxygenation to green diesel. Ni/Al2O3-ZrO2 and Ni/SiO2-ZrO2 were synthesized by wet-impregnation and hydrodeoxygenation of WCO was done using a modified batch reactor. The catalysts were characterized using X-ray diffraction (XRD), Xray fluorescence (XRF), and scanning electron microscopy - energy dispersive X-ray spectroscopy (SEM-EDS), and N2 isotherm adsorption-desorption analysis. Gas chromatography - mass spectrometry (GC-MS) analysis showed the formation of hydrocarbon framework n-C15 generated from the use of Ni/Al2O3-ZrO2 with the selectivity of 68.97% after a 2 h reaction. Prolonged reaction into 4 h, decreased the selectivity to 58.69%. Ni/SiO2-ZrO2 catalyst at 2 h showed selectivity of 55.39% to n-C15. Conversely, it was observed that the reaction for 4 h increased selectivity to 65.13%. Overall, Ni/Al2O3-ZrO2 and Ni/SiO2-ZrO2 catalysts produced oxygen-free green diesel range (n-C14-C18) enriched with n-C15 hydrocarbon. Reaction time influenced the selectivity to n-C15 hydrocarbon. Both catalysts showed promising hydrodeoxygenation activity via the hydrodecarboxylation pathway. [ABSTRACT FROM AUTHOR]