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A series of Ca 0.98− x MoO 4 :Dy 3+ 0.02 ,M + x (M = Li, Na, K, 0 ≤ x ≤ 0.16) phosphors were synthesized rapidly using microwave radiation method in 30 min. The effects of doping alkali metal ions on the phase structure and luminescent properties of the phosphors were analyzed using X-ray powder diffraction, scanning electron microscopy, fourier transform infra-red spectroscopy, and fluorescence spectrophotometry. The results confirmed that all the samples were pure tetragonal CaMoO 4 structure. The samples consisted of many cubic particles and some irregular polyhedron particles, assembled by fine spherical-like grains. The main emission peak was located at 574 nm, which was attributed to the 4 F 9/2 → 6 H 13/2 transition of Dy 3+ . The addition of alkali metal ions could effectively improve the intensity of the main emission peak. K + had better improvement on emission intensity than Na + and Li + . For the series of Ca 0.98− x MoO 4 :Dy 3+ 0.02 ,K + x phosphors, the optimum doping content of K + was 0.10 with 2.6 times of the emission intensity at 574 nm of the undoped-K + sample. The color coordinates gradually shifted from yellow-green region to the yellow region with the increasing of K + content (0 ≤ x ≤ 0.10). When x = 0.10, the sample shows the strongest yellow-emitting. [ABSTRACT FROM AUTHOR]

Soft magnetic Fe 72.7 Al 0.8 Si 17.5 B 5 Cu 1 Nb 3- x Ge x ( x = 0, 0.2, 0.4, 0.6, 0.8 and 1.0) amorphous alloys were produced by the single roller melt spinning method. The effects of Ge substitution for Nb on the microstructure and magnetic properties were investigated. Magnetic properties of all the alloys annealed at different temperatures were measured by the temperature dependence of initial permeability ( μ i - T curves) from the ambient temperature up to 650 ° C. Structure and crystalline process have been analyzed by XRD patterns and DSC curves, respectively. Partial substitution of Nb by Ge enhanced the Curie temperatures of amorphous phase and crystalline phase, and therefore improved the soft magnetic properties at high temperature. The Fe 72.7 Al 0.8 Si 17.5 B 5 Cu 1 Nb 2.6 Ge 0.4 alloy annealed at 570 ° C for 0.5 h shows the optimum high-temperature μ i , together with higher room-temperature μ i . The origin of the improved magnetic softness both at room- and high-temperature was analyzed. [ABSTRACT FROM AUTHOR]