Coal bio-oil slurries (CBS) with different coal concentrations were prepared by mixing different type of coal and bio-oil. The apparent viscosity, rheological properties, maximum solid concentration and static stabili...
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Coal bio-oil slurries (CBS) with different coal concentrations were prepared by mixing different type of coal and bio-oil. The apparent viscosity, rheological properties, maximum solid concentration and static stability of the prepared CBS were examined. The result shows that CBS are non-Newtonian fluid with a certain yield stress, and the rheological behavior of CBS can be described by the Bingham plastic fluid model. Both the apparent viscosity and the yield stress of CBS increase with increasing of solid concentrations. The apparent viscosity decreases with increasing of shear rates. The solid concentration of stable CBS prepared by Yangquan anthracite can reach as high as 42% without any additives, followed by bituminous coal and lignite. The flocculation network structure formed by coal particles in the bio-oil can keep good static stability of CBS for 4.0~5.0 days without formation of soft sediment, and for months without hard sediment.
Imines play a pivotal role as multifunctional intermediates in pharmaceutical and biological applications, and their selective synthesis under mild conditions has attracted increasing interest. In this study, a covale...
Imines play a pivotal role as multifunctional intermediates in pharmaceutical and biological applications, and their selective synthesis under mild conditions has attracted increasing interest. In this study, a covalent-organic frameworks (COFs) modified with CeO 2 quantum dots (QDs) were prepared through a simple chemical reaction using LZU1 COFs and Ce(NO 3 ) 3 ·6H 2 O serving as precursors. The optimized 5CeO 2 QDs@LZU1 decorated with about 3.9 wt% CeO 2 QDs demonstrates excellent performance in the photocatalytic selective oxidative of amines in visible light conditions, achieving nearly 100% benzylamine conversion and over 99% imine selectivity within 6 h, which is significantly superior to that of pure LZU1 and CeO 2 . The remarkable enhancement in activity is mainly attributed to the fact that the interaction between CeO 2 QDs and LZU1 COF in 5CeO 2 QDs@LZU1 improves the visible light response and concurrently promotes the separation efficiency of photogenerated e ‒ and h + pairs. Broad substrate scope also provides a prospect for the industrial synthesis of various imines. Our findings not only expand the application range of COFs by incorporating QDs but also lay the groundwork for their further rational design and optimization.
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