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Fouling is one of the barriers to developing more efficient and near-zero emission internal combustion engines. The micron-sized particulate matter is one of the roots of this fouling phenomenon in exhaust gas recirculation (EGR) coolers. This fouling is inadequately evaluated quantitatively, and its deposition mechanism is unknown. To investigate the effect of gravity on the deposition of micron-sized particles, an original nondestructive sampling fouling method and experiment apparatus have been developed to effectively obtain the upper and lower bottom fouling in the cooler in the direction of airflow, and the area proportion, count, and diameter of large particles in the fouling using image processing software. It was found that (i) the area proportion of large particles in the lower bottom fouling was almost 2.5 times higher than the upper bottom fouling; (ii) the count of large particles in the lower bottom fouling was higher, and the maximum diameter was larger, up to 639mm; (iii) the mass of the lower bottom fouling was 1.5 times higher than the upper bottom fouling; (iv) gravity can significantly promote the deposition of micron-sized particles and should be considered in the design and arrangement of the EGR cooler to prevent fouling. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are one of the main contributors to air pollution. To reduce anthropogenic emissions, it is necessary to improve existing techniques such as catalytic oxidation through the development of new cost‐effective catalysts. Although many studies deal with the development and testing of new materials, most are performed at laboratory scale, of which only a few study mixtures of VOCs. To assess their viability for industrial applications, further tests are required, namely, mixture tests at intermediate scale in relevant environment and extrapolated on an industrial scale. In this work, the catalytic performance of a new mixed oxide Co‐Al‐Ce was investigated towards the oxidation of the n‐butanol and toluene on a semi‐pilot scale (TRL 4). Single component and mixture experiments were performed for several concentrations at a fixed flow rate. A commercial catalyst Pd/γ‐Al2O3 was used as the benchmark to evaluate the performance of the mixed oxide. The Co‐Al‐Ce catalyst enables complete oxidation of n‐butanol at the same temperature as the reference catalyst. Moreover, it provides a better selectivity for n‐butanol, while providing an equivalent one for the oxidation of toluene. In mixtures, the presence of n‐butanol promotes the oxidation of toluene for both catalysts but more significantly for the Co‐Al‐Ce catalyst. The presence of toluene inhibits the oxidation of n‐butanol for the Co‐Al‐Ce and promotes it for high conversions of n‐butanol for the Pd/γ‐Al2O3 catalyst. [ABSTRACT FROM AUTHOR]

A very promising and facile one-pot synthesis pathway is presented for the microencapsulation of live cells in a very porous core–shell system based upon a robust matrix. (Alginate–SiO2–polycation) shell@(alginate–SiO2) core hybrid beads, on the millimeter scale, containing live cells are obtained through cross-linking chemistry and the polycondensation of silicic acid in conjunction with the use of a polycation to negate the surface charge on silica. Very interestingly it is revealed that the polycation used (PDADMAC) plays a very important role in the formation of highly robust core–shell beads. PDADMAC acts as a catalyst in the polycondensation of silicic acid, leading to the formation of a resistant double layer shell comprising of an interior layer of alginate–SiO2 with a very homogeneous distribution of porous SiO2 and an external layer of porous PDADMAC that confines SiO2 within the bead. The photosynthetic chlorophyta Dunaliella tertiolecta, which produces high value metabolites (such as anti-oxidants, pharmacologically active compounds, neutraceuticals etc.) via photosynthesis, has been encapsulated within this core–shell system. Oximetry and fluorescence measurements highlight how this algal culture can remain photosynthetically active over an extraordinarily long period of 13 months for high value compound production, whilst entrapped within a highly porous, mechanically and chemically stable, optically transparent matrix, with no observable leaching of the cells from the core of the beads. HPLC has been employed to highlight the presence of excreted metabolites, based on neutral sugar building blocks such as arabinose, galactose and xylose, in the surrounding media. These results reveal how this kind of high performance, low-cost, and easily scaleable core–shell living material could be employed in large scale photobioreactors (PBRs), to potentially facilitate metabolite harvesting whilst protecting the culture from external contamination and for green energy production and environmental (CO2) remediation. [ABSTRACT FROM AUTHOR]