發送短信

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

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發送短信 : A visual study of vortex rings fired transversely into a cross-flow