1.1 本试验方法涵盖了使用沸石X射线衍射图中选定的峰测定a沸石钠（NaA沸石）相对结晶度的程序。 1.2 术语“X射线粉末衍射（XRD）峰的强度”是指“积分强度”，即峰下的面积或计数，或峰高和半高处峰宽的乘积。 1.3 该测试方法提供了一个数字，即样品XRD图案部分的强度与参考沸石NaA图案相应部分的强度之比。 强度比以百分比表示，然后标记为NaA的相对结晶度。 1.4 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 沸石NaA已被用作分子筛中的活性成分，用作天然气、工艺气流、密封隔热窗户的干燥剂，以及家用洗衣洗涤剂中的助洗剂（软水剂）。 4.2 该X射线程序旨在报告NaA制造过程中NaA的相对结晶度。相对结晶度数值在技术、研究和规范中已被证明是有用的。 4.3 NaA分子筛晶胞内电子密度分布的变化可能导致NaA XRD图谱中单个峰强度的剧烈变化。电子密度分布取决于客体分子填充沸石孔的程度以及客体分子的性质。 在这种XRD方法中，客体分子H 2. O完全填充毛孔。如果NaA中的部分或全部钠阳离子被其他阳离子交换，也可能导致强度变化。 4.4 NaA样品中非晶相（如果存在）引起的X射线吸收变化可能导致总强度的剧烈变化。如果存在非沸石晶相，其衍射峰可能与本试验方法选择的一些NaA衍射峰重叠。 如果有理由怀疑存在此类成分，则应选择无干扰的NaA峰进行分析。

1.1 This test method covers a procedure for determining the relative crystallinity of zeolite sodium A (zeolite NaA) using selected peaks from the X-ray diffraction pattern of the zeolite. 1.2 The term “intensity of an X-ray powder diffraction (XRD) peak” refers to the “integral intensity,” either the area or counts under the peak or the product of the peak height and the peak width at half height. 1.3 This test method provides a number that is the ratio of intensity of portions of the XRD pattern of the sample to intensity of the corresponding portion of the pattern of a reference zeolite NaA. The intensity ratio, expressed as a percentage, is then labeled relative crystallinity of NaA. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 4.1 Zeolite NaA has been used as an active component in molecular sieves employed as desiccants for natural gas, process gas streams, sealed insulated windows, and as a builder (water softener) in household laundry detergents. 4.2 This X-ray procedure is designed to allow a reporting of the relative degree of crystallization of NaA in the manufacture of NaA. The relative crystallinity number has proven useful in technology, research, and specifications. 4.3 Drastic changes in intensity of individual peaks in the XRD pattern of NaA can result from changes in distribution of electron density within the unit cell of the NaA zeolite. The electron density distribution is dependent upon the extent of filling of pores in the zeolite with guest molecules, and on the nature of the guest molecules. In this XRD method, the guest molecule H 2 O completely fills the pores. Intensity changes may also result if some or all of the sodium cations in NaA are exchanged by other cations. 4.4 Drastic changes in overall intensity can result from changes in X-ray absorption attributed to non-crystalline phases, if present, in a NaA sample. If non-zeolite crystalline phases are present, their diffraction peaks may overlap with some of the NaA diffraction peaks selected for this test method. If there is reason to suspect the presence of such components, then NaA peaks free of interference should be chosen for analysis.