“Penny Black Stamp”的概念、定义、翻译、参考文献-科学参考

单词	Penny Black Stamp
释义	Penny Black Stamp Encyclopedia 工学邮资凭证释 Penny Black Stamp黑便士 1840年英国发行的世界上第一枚邮票。5月1日发售，5月6日正式使用。面值为1便士，用黑色油墨印制。
随便看	equivalent electron equivalent element equivalent enumerations equivalent equation equivalent equations equivalent events equivalent exchange equivalent extensions equivalent extensions of a field equivalent extensions of a group equivalent fiber bundle equivalent flow equivalent focal distance equivalent focal length equivalent focus equivalent force equivalent force system equivalent forms equivalent formula equivalent functions equivalent graphs equivalent grinding thickness equivalent group equivalent infinitesimals equivalent isotropic radiated power

科学参考收录了854744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。