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| || | || | || | || | \  / ||  /_   _//  / ____|| 
| || | || | || | || |  \/  ||   -| ||-  / //---`' 
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  `---`     `---`   `-`  `-`   `-----`    `----`

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Text this: Optical and luminescence properties of Pr<sup>3+</sup> in Gd<inf>2</inf>O<inf>3</inf>-CaO-SiO<inf>2</inf>-B<inf>2</inf>O<inf>3</inf> glasses