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A new Keggin-type polyoxometalate-based supramolecular complex 1, namely H3 [ (3-PA)4 ( PW12O40) ] (3-PA = 3-Pyridineacrylic acid), was successfully synthesized under hydrothermal conditions and structurally characterized by single crystal X-ray diffraction, elemental analysis ( EA), IR spectra, PXRD, TG and UV-Vis diffuse-reflectance. Complex 1 crystallizes in the triclinic system, P-1 space group with α = 1. 200 33(3) nm, b = 1.216 42(3) nm, c = 1. 424 66(4) nm, α =75.030(1)°, β =73.452(1)°, γ =69.372(1)°, V = 1.837 00(8) nm³, Z = 1, Mr =3 476.78, F(000) = 1 538, µ = 18. 815 mm-1, Dc = 3. 143 mg⋅m-3, S = 1. 062, R1 = 0. 046 2, wR2 = 0. 138 7. The structural unit of complex 1 consists of a [PW12O40]3- ployanion and four 3-PA ligands. In addition, [PW12O40]3- polyanion and 3-PA ligands are linked by H-bonds to form 2-D supramolecular layer. When using as photocatalyst, complex 1 displayed excellent photocatalytic activity towards the reduction of Cr( W) with good structural stability and recyclability. [ABSTRACT FROM AUTHOR]

In order to study the influence of laminated structures of carbon fiber reinforced polymer (CFRP) on the temperature under continuous wave (CW) laser irradiation, the ablation processes of five typical laminated CFRPs irradiated by CW laser were simulated by using finite element software COMSOL. The temperature distribution and evolution of five typical laminated composites were obtained by the temperature deviation of the material surface. Meanwhile, based on analyzing the overall temperature distribution of the materials statistically, the variations of the temperature uniformity of the materials with the laser irradiation time were obtained. The results show that the surface temperature near the edge of the spot is most sensitive to the laminated structure in unidirectional ply CFRPs and the temperature curve is nonmonotonic. Moreover, the temperature uniformity of CFRP with 45° angle laminated structure is the best in the five types. The results of this work can be referenced for the study of thermomechanics damage of CFRP induced by laser. [ABSTRACT FROM AUTHOR]