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Abstract: Pepper processing waste has the potential to be used as a substrate in the process of anaerobic digestion, but because of its high polyphenol content, certain limitations are expected. During the determination of the biodegradability of pepper samples, a biogas potential of 687 L/kg DM was observed, as well as a biomethane potential of 401 L/kg DM. While both the testing of biodegradability and the process in the pilot scale progressed, it was observed that total polyphenol content in both cases decreased. Also, as far as individual polyphenols during the process in the pilot scale are concerned, it can be observed that at the end of the process no procyanidin A2, epicatechin, myricetin, and quercetin were detected. The observed concentration of the ferulic acid on the last day of the process was 0.09 μg/g. Finally, it can be concluded that the presence of polyphenols did not significantly affect the biogas potential of pepper waste. Due to its relatively stable biogas production, as far as biogas production on the pilot scale is concerned, it can be concluded that pepper processing waste has the potential to be used as a substrate for biogas production.
Keywords: anaerobic digestion, polyphenols, ferulic acid, procyanidins, epicatechin, myricetin, quercetin
Published in RUNG: 06.05.2024; Views: 258; Downloads: 2
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Abstract: The present work delineates the tailoring of the thermal effusivity and diffusivity of the novel class of heat transfer fluids—ionanofluids—by the incorporation of nanocarbons like diesel soot (DS), camphor soot (CS), carbon nanotubes (CN), and graphene (GR). When the thermal diffusivity delivers information on the thermal energy propagation, the thermal effusivity concerns the energy exchange at the interface, enabling energy-efficient thermal system design. The nanocarbons are subjected to morphological characterisation by field emission scanning electron microscopy. Fourier-transform infrared and Raman spectroscopic analyses confirm functional groups and vibrational bands. The microcrystalline size and graphiticity are also understood from the Raman spectrum. Ionanofluids prepared by dispersing nanocarbons into an ionic liquid base 1-Butyl-3-methylimidazolium methyl sulfate (BMMS) are analysed by nondestructive photopyroelectric calorimetry (PPE). The PPE analysis of ionanofluids demonstrates that nanocarbons influence thermal parameters in the base fluid, with soot ionanofluids exhibiting increased thermal effusivity and diffusivity due to their various carbon allotropic composition. This study underscores the importance of selecting the appropriate carbon allotrope for tailoring ionanofluids’ thermal properties, providing insights into manipulating these properties for enhanced performance across various industrial applications.
Keywords: photopyroelectric, ionanofluid, soot, graphene, thermal diffusivity
Published in RUNG: 06.05.2024; Views: 264; Downloads: 3
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Abstract: Hydrodechlorination reaction of 3-(benzo-1,3-dioxol-5-yl)-3-chloro-2-methylacrylaldehyde in the presence of different low metal content heterogeneous mono- or bimetallic catalysts was tested for the synthesis of the fragrance Helional® (3-[3,4-methylendioxyphenyl]-2-methyl-propionaldehyde). In particular, mono Pd/Al2O3, Rh/Al2O3 or bimetallic Pd-Cu/Al2O3, Rh-Cu/Al2O3 catalysts were tested in different reaction conditions from which it emerged that mono-Rh/Al2O3 was the best performing catalyst, allowing achievement of 100% substrate conversion and 99% selectivity towards Helional® in 24 h at 80 °C, p(H2) 1.0 MPa in the presence of a base. To establish correlations between atomic structure and catalytic activity, catalysts were characterized by Cu, Rh and Pd K-edge XANES, EXAFS analysis. These characterizations allowed verification that the formation of Pd-Cu alloys and the presence of Cu oxide/hydroxide species on the surface of the Al2O3 support are responsible for the very low catalytic efficiency of bimetallic species tested.
Keywords: selective hydrodechlorination, heterogeneous catalysis, XANES analysis, EXAFS analysis
Published in RUNG: 25.04.2024; Views: 527; Downloads: 4
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Abstract: The present invention belongs to the field of devices and methods for measurement of particle concentration, more precisely to the field of devices and methods for quantification of particles based on their physical characteristics, especially with the use of optical means. The invention relates to a method for determination of ambient mineral dust concentration based on optical absorption of particles concentrated by a virtual impactor as well as a device performing the said method. The method comprises the following steps:- Sampling air samples with particle size smaller than 1 µm (PM1) and sampling air samples with particle size up to 10 µm;- Concentrating the samples with particle sizes up to 10 µm with a virtual impactor;- Measuring optical absorption of collected samples at least one wavelength from UV to IR spectre, preferably from 370 to 950 nm, most preferably at 370 nm;- Subtracting the absorption of the samples with particle size smaller than 1 µm from the absorption of the sample concentrated by the virtual impactor.
Keywords: dust, black carbon, aerosols
Published in RUNG: 24.04.2024; Views: 917; Downloads: 2
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Keywords: turbo-folk, queer kultura
Published in RUNG: 22.04.2024; Views: 610; Downloads: 2
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