“首日封”的概念、定义、翻译、参考文献-科学参考

单词	首日封
释义	首日封 Encyclopedia 工学集邮品释 first day cover首日封在新邮票发行首日，将该套邮票的全套或单枚贴在特制信封、普通信封或纪念信封的右上角，加盖当日邮政日戳或特制的首日纪念邮戳的信封。
随便看	precipitation amount in China precipitation bias scores precipitation change experiment precipitation chemistry precipitation days in China precipitation/dissolution precipitation dissolution equilibrium precipitation form precipitation fractionation precipitation from homogeneous solution precipitation gravimetry precipitation hardening precipitation hardening iron-based cast and wrought superalloy precipitation hardening nickel based cast and wrought superalloy precipitation in China precipitation intensity in China precipitation masking method precipitation measuring instrument precipitation measuring instrument based on light intensity attenuation precipitation measuring instrument based on linear-array-imaging technique precipitation-measuring radar precipitation method precipitation number precipitation observation precipitation of insoluble compounds

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。