Fe-Cr-B-Si-Mn-Nb-Y and Fe-B-Si-Nb-Cr amorphous/nanocrystalline coatings were fabricated by wire arc spray process. The microstructure and phase compositions of the coatings were characterised by means of SEM, EDAX and XRD. The formation mechanism of amorphous phase and nanocrystalline phase was discussed. The elevated temperature erosion behaviour of the coatings was also investigated using an air solid particle erosion rig. The microstructures of the coatings consist of amorphous phase and a-(Fe,Cr) nanocrystalline phase. Both coatings are fully dense with low porosity. The coatings exhibit better erosion resistance at lower impact angles. With increasing erosion temperature, the erosion rates of the coatings decrease. The Fe-B-SiNb-Cr coating has better elevated temperature erosion resistance than that of the Fe-Cr-B-SiMn-Nb-Y coating.

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Abstract:A new β-diketone, 2,2,2-trifluoro-1-(4-hydroxy-2H-chromen-3-yl)ethanone (4-TFC), which contains a trifluorinated alkyl group and a rigid chromanone, has been designed and synthesised successfully, and utilized for the synthesis of a new stable Eu 3+ ion-based 4-TFC lanthanide complex (1). The central Eu 3+ ion is eight-coordinated by two O/N atoms from ancillary ligands and six oxygen atoms provided by three 4-TFC ligands. In particular, the complex (1) can detect Al 3+ ions with high selectivity and sensitivity in a moment and can be seen by the naked eye clearly under 365 nm. The experimental data can be explained with the calculated transitions quite well.

C13H10BF5O3, triclinic, P1̄ (no. 2), a = 7.737(2) Å, b = 7.8600(19) Å, c = 11.803(3) Å, α = 82.03(2)°, β = 76.91(2)°, γ = 69.69(2)°, V = 654.2(3) Å3, Z = 2, Rgt(F) = 0.0471, wRref(F2) = 0.1203, T = 293 K.