發送短信

數:

提供者:

CAPTCHA:

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

Please enter what you see:

發送短信 : Optimal energy transfer pipe arrangement for acoustic drill string telemetry