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  ____       ___     _    _    _    _    _____    
 |  _ \\    / _ \\  | || | || | || | || |  __ \\  
 | |_| ||  | / \ || | || | || | || | || | |  \ || 
 | .  //   | \_/ || | \\_/ || | \\_/ || | |__/ || 
 |_|\_\\    \___//   \____//   \____//  |_____//  
 `-` --`    `---`     `---`     `---`    -----`

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Text this: Green electroluminescence from an n-ZnO : Er/p-Si heterostructured light-emitting diode