The construction of an appropriate support for a single atom catalyst plays an important role in delivering a high catalytic performance. However, most reported host materials suffer the drawbacks of low photostability and limited visible light absorption. Herein, we report a porous organic cage as a high-quality support for single metal atoms by a facile stepwise nucleophilic substitution approach. Thanks to its intrinsic advantages of extended visible light absorption, suppressed charge recombination, and improved electron transfer, the obtained single Co atoms anchored organic cage (CoP@POC) demonstrates a prominent photocatalytic efficiency for oxidation of amines into imines in visible light. An excellent reaction conversion and selectivity up to 99%, associated with a turnover frequency (TOF) of 1389 h–1 and 22 989 mmol g–1 h–1 are achieved based on organic cage and single Co atoms, respectively, which outperforms most reported photocatalysts. Moreover, a negligible conversion decrease in 5 repeating cycles and no photobleaching after the reaction was detected, implying a remarkable photostability of CoP@POC.

The relationship between growth rates of algae and structure parameters of closed flat-panel photobioreactors was investigated. Ad/Ar (cross-section area of the downcomer/cross-section area of the riser), h 0 (clearance from the upper edge of the baffles to the water level), and h 1 (clearance from the lower edge of the baffles to the bottom of the reactor) were selected as the inner structure parameters. CFD (Computational Fluid Dynamics) was used to simulate the hydrodynamic parameter (TKE) d (turbulence kinetic energy of the downcomers) and the secondary parameters ε (ratio between td and tc), tc (cycle time), and DZ (dead zones), which were deduced from the hydrodynamic parameters mentioned above. The effects of (TKE) d, ε, tc, DZ, and the inner structure parameters on cell growth of Isochrysis galbana 3011 were analyzed using data collected in 15-L airlift flat-panel photobioreactors. A model was developed to predict algae cell growth based on these inner structure parameters, thereby providing a new method for photobioreactor optimization. Validity of the model was confirmed by experimental data of I. galbana 3011 cultured in 15-L and 300-L photobioreactors, respectively. Finally, the prospect of applying CFD to photobioreactor optimization was discussed.

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The difference of the aerodynamic influence of two engine models -the Flow Through Nacelle (FTN) and With Powered Nacelle (WPN) -on BWB300 airframe is analyzed by using the 3-D unsteady compressible Reynolds-Averaged Navier-Stokes (RANS) computation. The results indicate that at cruise condition, the engine shape is a primary factor affecting the BWB airframe upper fuselage surface flow, the two engine models exhibit a similar aerodynamic influence on the BWB airframe. However, at takeoff condition, the two engine models' aerodynamic influence on the airframe is different, because of the air suction caused by the WPN engine model affecting the airframe upper fuselage surface flow obviously. Moreover, at both cruise and takeoff conditions, the tube formed by the engine and airframe shape changes the surface flow under the engine and the air suction caused by the engine power accelerates the surface flow near the engine. ARTICLE HISTORY