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Synthesis of framework materials possessing specific spatial structures or containing functional ligands has attracted tremendous attention. Herein, a halogen hydrogen-bonded organic framework (XHOF) is fabricated by using Cl− ions as central connection nodes to connect organic ligands, 7,7,8,8-tetraaminoquinodimethane (TAQ), by forming a Cl−···H3 hydrogen bond structure. Unlike metallic node-linked MOFs, covalent bond-linked COFs, and intermolecular hydrogen bond-linked HOFs, XHOFs represent a different kind of crystalline framework. The electron-withdrawing effect of Cl− combined with the electron-rich property of the organic ligand TAQ strengthens the hydrogen bonds and endows XHOF-TAQ with high stability. Due to the production of excited electrons by TAQ under light irradiation, XHOF-TAQ can efficiently catalyze the reduction of soluble U(VI) to insoluble U(IV) with a capacity of 1708 mg-U g−1-material. This study fabricates a material for uranium immobilization for the sustainability of the environment and opens up a new direction for synthesizing crystalline framework materials. While hydrogen bonded organic frameworks are well covered in the scientific literature, halogen hydrogen-bonded organic framework (XHOF) remain less explored. Here, the authors demonstrate a highly stable diradical-based XHOF and demonstrate photoreduction of uranyl ions and high capacity of uranyl immobilization. [ABSTRACT FROM AUTHOR]

The optimal energy management for a plug-in hybrid electric bus (PHEB) running along the fixed city bus route is an important technique to improve the vehicles' fuel economy and reduce the bus emission. Considering the inherently high regularities of the fixed bus routes, the continuous state Markov decision process (MDP) is adopted to describe a cost function as total gas and electric consumption fee. Then a learning algorithm is proposed to construct such a MDP model without knowing the all parameters of the MDP. Next, fitted value iteration algorithm is given to approximate the cost function, and linear regression is used in this fitted value iteration. Simulation results show that this approach is feasible in searching for the control strategy of PHEB. Simultaneously this method has its own advantage comparing with the CDCS mode. Furthermore, a test based on a real PHEB was carried out to verify the applicable of the proposed method. [ABSTRACT FROM AUTHOR]

Plants can change leaf forms, adjusting light conditions on their adaxial and abaxial surfaces, to adapt to light environments and enhance their light use efficiencies. The difference between photosynthesis on the two leaf sides (dorsoventral asymmetry) is an important factor that affects light use efficiency. However, photosynthetic dorsoventral asymmetry is rarely compared under direct and diffuse light conditions. To estimate the impacts of recently reported alterations in direct and diffuse light in the sky radiation on plant carbon assimilation, variations in morphology between the two leaf sides in tobacco (Nicotiana tabacum L.) were investigated, and the dorsoventral responses of photosynthesis to illuminating directions were compared in direct and diffuse light. Dorsoventral asymmetry was reflected in stomatal densities, anatomic structures, and photochemical traits, which caused markedly different photosynthetic rates as well as stomatal conductances both in direct and diffuse light. However, the degree of photosynthetic asymmetry was weakened in diffuse light. The diffuse light caused a greater stomatal conductance on the abaxial side than direct light, which resulted in reduced photosynthetic asymmetry. In addition, the photosynthetic dorsoventral asymmetry could be affected by the photosynthetic photon flux density. These results contribute to understanding the dorsoventral regulation of photosynthesis in bifacial leaves, and provide a reference for breeding to cope with the increase in the proportion of diffuse light in the future. [ABSTRACT FROM AUTHOR]