1.1 本试验方法包括通过X射线粉末衍射法测定含二氧化硅和氧化铝的催化剂和催化剂载体中的γ-氧化铝和相关过渡铝，使用铜Kα辐射时在约67°2θ处出现的峰值衍射强度。 1.2 单位- 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。 1.3 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。 1.4 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 本试验方法用于估计煅烧催化剂或催化剂载体样品中γ-氧化铝的相对含量，假设在约67°2θ处出现的X射线粉末衍射峰可归因于γ-氧化铝。γ-氧化铝是指在500至550范围内加热后形成的过渡氧化铝 °C，可能包括文献中描述的形式，如eta、chi和γ-铝。δ氧化铝在同一区域有衍射峰，但在850以上形成 °C，大多数此类催化剂未加热到的温度。 还有其他可能引起干扰的成分，如α石英和Y沸石，以及在高温下形成的含铝尖晶石。如果怀疑存在干扰物质，则应更详细地检查衍射图案。更显著的干扰可能是由于存在大量重金属或稀土，这些重金属或稀土表现出强烈的X射线吸收和散射。因此，类似材料之间的比较可能比广泛变化的材料之间的比较更合适。

1.1 This test method covers the determination of gamma alumina and related transition aluminas in catalysts and catalyst carriers containing silica and alumina by X-ray powder diffraction, using the diffracted intensity of the peak occurring at about 67 °2θ when copper Kα radiation is employed. 1.2 Units— The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 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. 1.4 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 This test method is for estimating the relative amount of gamma alumina in calcined catalyst or catalyst carrier samples, assuming that the X-ray powder diffraction peak occurring at about 67 °2θ is attributable to gamma alumina. Gamma alumina is defined as a transition alumina formed after heating in the range from 500 to 550 °C, and may include forms described in the literature as eta, chi, and gamma aluminas. Delta alumina has a diffraction peak in the same region, but is formed above 850 °C, a temperature to which most catalysts of this type are not heated. There are other possible components which may cause some interference, such as alpha-quartz and zeolite Y, as well as aluminum-containing spinels formed at elevated temperatures. If the presence of interfering material is suspected, the diffraction pattern should be examined in greater detail. More significant interference may be caused by the presence of large amounts of heavy metals or rare earths, which exhibit strong X-ray absorption and scattering. Comparisons between similar materials, therefore, may be more appropriate than those between widely varying materials.