“primary center”的概念、定义、翻译、参考文献-科学参考

单词	primary center
释义	primary center [`prī´mer·ē `sen·tǝr] ^{COMMUNICATIONS} A telephone office having lower rank than a sectional center and higher rank than a toll center; connects toll centers and may also serve as a toll center for nearby end offices.
随便看	control surface control switching point control symbol control synchro control system control-system feedback control systems equipment control tape control total control tower control-tower visibility control track control transformer control unit control unit terminal emulation control valve control vane control variable control winding control word control zone contusion Conularida Conulata Conulidae

科学参考收录了103327条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。