Ca Al O :Eu , Ca Al O :Dy and Ca Al O :Tb phosphors were synthesized using a combustion synthesis method. The prepared phosphors were characterized by X-ray powder diffraction for phase purity, by scanning electron microscopy for morphology, and by photoluminescence for emission and excitation measurements. The Ca Al O :Eu phosphors could be efficiently excited at 396 nm and showed red emission at 594 nm and 616 nm due to D → F and D → F transitions. Dy -doped phosphors showed blue emission at 482 nm and yellow emission at 573 nm. Ca Al O :Tb phosphors showed emission at 545 nm when excited at 352 nm. Concentration quenching occurred in both Eu and Dy phosphors at 0.5 mol%. Photoluminescence results suggested that the aluminate-based phosphor could be a potential candidate for application in environmentally friendly based lighting technologies.

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We have studied the proton decay in almost all superheavy nuclei with atomic number Z = 104–126. We have calculated the energy released during the proton decay (QP), penetration factor (P), normalization factor (F), and the proton decay half-lives. The latter are also longer than that of other decay modes such as the alpha decay and spontaneous fission. The competition of the proton decay with different decay modes reveals that the proton decay is not the dominant decay mode in the superheavy nuclei region. This means that superheavy nuclei are stable against the proton decay.