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

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發送短信 : Rotational isomerism in 2,3-dinitro-2,3-dimethylbutane