The National Institute of Standards and Technology (NIST) certifies a suite of Standard Reference Materials (SRMs) to address specific aspects of the performance of X-ray powder diffraction instruments. This report describes SRM 1879b, the third generation of this powder diffraction SRM. SRM 1879b is intended for use in the preparation of calibration standards for the quantitative analyses of cristobalite by X-ray powder diffraction in accordance with National Institute for Occupational Safety and Health (NIOSH) Analytical Method 7500, or equivalent. A unit of SRM 1879b consists of approximately 5 g of cristobalite powder bottled in an argon atmosphere. It is certified with respect to crystalline phase purity, or amorphous phase content, and lattice parameter. Neutron powder diffraction, both time-of-flight and constant wavelength, was used to certify the phase purity using SRM 676a as an internal standard. A NIST-built diffractometer, incorporating many advanced design features was used for certification measurements for lattice parameters.

中文翻译：

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标准参考物质 1879b 可吸入方石英的认证

美国国家标准与技术研究院 (NIST) 认证了一套标准参考材料 (SRM)，以解决 X 射线粉末衍射仪器性能的特定方面。本报告描述了 SRM 1879b，这是该粉末衍射 SRM 的第三代。SRM 1879b 旨在用于根据美国国家职业安全与健康研究所 (NIOSH) 分析方法 7500 或等效方法制备通过 X 射线粉末衍射对方石英进行定量分析的校准标准品。一个 SRM 1879b 单元由大约 5 克装在氩气气氛中的方石英粉末组成。它通过了结晶相纯度或非晶相含量和晶格参数的认证。中子粉末衍射，飞行时间和恒定波长，用于使用 SRM 676a 作为内标物来证明相纯度。NIST 制造的衍射仪结合了许多先进的设计功能，用于晶格参数的认证测量。