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

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Text this: Hollow carbon spheres with a controllable shell structure