ASTM D6341-2021 实施日期：2021-01-15      英文名：Standard Test Method for Determination of the Linear Coefficient of Thermal Expansion of Plastic Lumber and Plastic Lumber Shapes Bet

 ASTM D6341-2021 实施日期：2021-01-15      英文名：Standard Test Method for Determination of the Linear Coefficient of Thermal Expansion of Plastic Lumber and Plastic Lumber Shapes Bet

 ISO 17420-4-2021 实施日期：2021-01-11        Respiratory protective devices — Performance requirements — Part 4: Requirements for supplied breathable gas RPD 

 CNAS TRL014-2021 实施日期：2021-01-01      科研数据特征划分及其分类体系表    

GY/T 344-2021 实施日期：2021-01-20      互联网电视内容服务平台技术要求    

  ETSI TS 129 333/2-2021 实施日期：2021-01-06      Digital Cellular Telecommunications System (Phase 2+) (Gsm); Universal Mobile Telecommunications System (Umts); Multimedia R