1.1 本试验方法包括测定溶解在均匀溶液中的发射伽马射线的特殊核材料的浓度。本试验方法通过测量来自外部源的伽马射线束的透射来校正溶液及其容器的伽马射线衰减（参考文献1）。 ( 1. ) , ( 2. ) 和 ( 3. ) ). 2. 1.2 考虑了两种求解几何形状:平板和圆柱。确定几何体的解决方案容器可以是可移动的或固定的几何体容器。本试验方法仅限于具有墙壁或顶部和底部等透射率的溶液容器，外部透射校正源的伽马射线必须通过这些容器。 1.3 该试验方法通常适用于放射性核素浓度范围从几毫克/升到几百克/升。分析范围取决于相关核素的比活度、溶液容器的物理特性、计数设备注意事项、分析γ射线能量、溶液基质、γ射线分支比和干扰。 1.4 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。 有关具体危险，请参阅第节 9 . 1.5 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====== 5.1 本试验方法是一种非破坏性方法，用于确定特殊核材料核算、核安全和过程控制溶液的核素浓度。 5.2 假设待分析的核素处于均匀溶液中（实践 C1168 ). 5.3 透射校正使测试方法独立于基质（溶液元素组成和密度），并在几个数量级的核素浓度上有用。 然而，由于探测器的动态范围，典型配置通常只跨越两到三个数量级。 5.4 试验方法假设溶液检测器几何形状对于所有测量项目都相同。这可以通过要求侧视几何形状中的液体高度超过准直器定义的探测器视野来实现。对于向上看的几何形状，必须保持固定的溶液填充高度，并且必须使用相同半径的小瓶，除非小瓶半径超过准直器定义的视野。 5.5 由于伽马射线系统可以自动化，因此测试方法可以快速、可靠且不需要劳动密集型。 5.6 本试验方法可适用于- 在线或离线情况。

1.1 This test method covers the determination of the concentration of gamma-ray emitting special nuclear materials dissolved in homogeneous solutions. The test method corrects for gamma-ray attenuation by the solution and its container by measurement of the transmission of a beam of gamma rays from an external source (Refs. ( 1 ) , ( 2 ) , and ( 3 ) ). 2 1.2 Two solution geometries, slab and cylinder, are considered. The solution container that determines the geometry may be either a removable or a fixed geometry container. This test method is limited to solution containers having walls or a top and bottom of equal transmission through which the gamma rays from the external transmission correction source must pass. 1.3 This test method is typically applied to radionuclide concentrations ranging from a few milligrams per litre to several hundred grams per litre. The assay range will be a function of the specific activity of the nuclide of interest, the physical characteristics of the solution container, counting equipment considerations, assay gamma-ray energies, solution matrix, gamma-ray branching ratios, and interferences. 1.4 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. For specific hazards, see Section 9 . 1.5 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 ====== 5.1 This test method is a nondestructive means of determining the nuclide concentration of a solution for special nuclear material accountancy, nuclear safety, and process control. 5.2 It is assumed that the nuclide to be analyzed is in a homogeneous solution (Practice C1168 ). 5.3 The transmission correction makes the test method independent of matrix (solution elemental composition and density) and useful over several orders of magnitude of nuclide concentrations. However, a typical configuration will normally span only two to three orders of magnitude because of detector dynamic range. 5.4 The test method assumes that the solution-detector geometry is the same for all measured items. This can be accomplished by requiring that the liquid height in the sidelooking geometry exceeds the detector field of view defined by the collimator. For the upward-looking geometry, a fixed solution fill height must be maintained and vials of identical radii must be used unless the vial radius exceeds the field of view defined by the collimator. 5.5 Since gamma-ray systems can be automated, the test method can be rapid, reliable, and not labor intensive. 5.6 This test method may be applicable to in-line or off-line situations.