“second category”的概念、定义、翻译、参考文献-科学参考

单词	second category
释义	second category [`sek·ǝnd `kad·ǝ´gȯr·ē] ^MATHEMATICS A set is of second category if it cannot be expressed as a countable union of nowhere dense sets.
随便看	coincidence correction coincidence counter coincidence counting coincidence effect coincidence gate coincidence magnet coincidence rangefinder coincidental evolution coincident-current selection co-inducer coin gold coining coinjection molding coin silver cointegrate structure coion coir coisogenic strain coitophobia coitus coke coke breeze coke coal coke drum cokeite

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。