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YSZ@Ni core–shell nanoparticles were used to prepare a composite coating on an Fe-based alloy by laser cladding. Samples were sintered layer-by-layer with a laser power P in the range of 800–2000 W, scanning velocity V in the range of 240–600 mm/min, and the laser beam diameter D =5 mm. The microstructures, phase constituents, and microhardness of a monolayer coating were investigated and compared with those of a multilayer coating. The results showed that the existing forms of core-YSZ in the monolayer coating comprised of four types: flower-like YSZ aggregates, few nanoscale YSZ particles at the grain boundaries, proeutectic YSZ phases, and YSZ/FeCr 2 O 4 eutectic structure. Moreover, the multilayer coating structure was more homogeneous than the monolayer one. Interestingly, the YSZ@Ni core–shell nanoparticles were separated into core-YSZ and shell-Ni layer with a stratification feature during the laser cladding process. [ABSTRACT FROM AUTHOR]

To protect Cr–50Nb alloys from high-temperature oxidation, the silicide diffusion coating and Si–Al coating were produced by pack cementation. The results indicate that the two coatings have three-layer structure and the interfaces are smooth. Uncoated Cr–50Nb alloy occur catastrophic oxidation at the initial oxidation stage at 1200 °C. However, the scale spalling resistance of the two coatings are improved significantly, and Si–Al coating exhibits excellent resistance to oxidation. During cyclic oxidation in air at 1200 °C for 100 h, the weight loss of Si–Al coating is 1.39 mg/cm 2 and the mass gain is 6.01 mg/cm 2 . [ABSTRACT FROM AUTHOR]

Abstract: The Lorentz and Lorentz–Gauss beams are extended to the nonparaxial regime. Analytical propagation expressions of nonparaxial Lorentz and Lorentz–Gauss beams in free space are derived, and the propagation of paraxial Lorentz and Lorentz–Gauss beams is treated as a special case of our general results. The propagation properties of Lorentz and Lorentz–Gauss beams are illustrated and compared with numerical examples. [ABSTRACT FROM AUTHOR]

Abstract: A method for the simulation and optimization of the source-field distribution of a diode bar laser (DBL) beam by using the stimulated annealing and experimental data in the far field is proposed and illustrated by an example of a DBL JOLD-60-CPNN-1L, showing the applicability of the method. As compared with the previous models, this method is not restricted to the type of diode lasers (DLs), and the reconstructed results are accurate so long as the experimental data are sufficiently accurate. [Copyright &y& Elsevier]

Abstract The uniform distribution of nano-sized conductive fillers in conductive papers is still a big challenge. Herein, we report a novel cycled film-liquid interface culture (CFLIC) method to produce flexible, ultra-strong, and highly conductive papers based on bacterial cellulose (BC) and graphene (GE). During this biosynthesis process, the GE nanosheets uniformly dispersed in the culture medium are closely bundled by growing BC nanofibers, which leads to a sophisticated multilayered GE/BC nanocomposite. The as-prepared GE/BC paper shows greatly improved tensile strength (93% improvement) and electrical conductivity (10 orders of improvement) over bare BC paper while still retaining the excellent flexibility of BC paper. The strategy is versatile, facile, and scalable and the resultant paper shows promise in numerous fields such as energy storage and electromagnetic interference shielding. Graphical abstract Image 1 Highlights • Flexible conductive papers were made via a film-liquid interface culture method. • The papers consist of bacterial cellulose and highly dispersed graphene nanosheets. • The papers show greatly improved tensile strength and electrical conductivity. [ABSTRACT FROM AUTHOR]