GB 20052-2024 Chinese PDF GB/T 45471-2025 2-2025_Chinese: Petroleum and natural gas

2-2025_Chinese: Petroleum and natural gas industries - Materials for use in H2S-containing environments in oil and gas production - Part 2: Cracking-resistant carbon and low alloy steels

1-2025_Chinese: Mobile laboratory - Part 1: General rule (Chinese: 移动实验室 第1部分：通则)

2-2025_Chinese: Optics and photonics - Test methods for telescopic systems - Part 2: Binoculars (Chinese: 光学和光子学 望远镜系统试验方法 第2部分：双筒望远镜)

GB/T 33796-2025_Chinese: General technical requirement of thermoplastic starch (Chinese: 热塑性淀粉通用技术要求)

English versions: GB/T 44981-2024

GB 20052-2024 Chinese PDF GB/T 45471-2025 2-2025_Chinese: Petroleum and natural gasGB 20052 2024_Chinese: Minimum allowable values of energy efficiency and the energy efficiency grades for power transformers (Chinese: ) Note Careful: Text of PDF is in Chinese (not English). Delivery (PDF in Chinese): 2 working hours typically, ASAP English versions: GB 20052 2024