1.1 本规程涵盖了制备固体、糊状或粉末植物鞣质提取物分析所需分析溶液的标准程序。 1.2 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 固体、糊状和粉末提取物中的单宁浓度需要降低到单宁分析的分析强度。 4.2 植物鞣质提取物是具有不同溶解度的成分的非均质混合物。 4.3 此类提取物的溶解度受温度和浓度的影响，而温度和浓度会影响组分颗粒的分散程度和大小。 4.4 由于提取物在热水中的溶解度大于在冷水中的溶解度，因此需要在热水中溶解和分散提取物，然后让溶液缓慢冷却至标准室温。 4.5 通常很难将固体特别是糊状提取物的样品缩小到样品尺寸，同时确保具有代表性的采样。因此，在得出关于此类提取物结果的精度和偏差的结论时应谨慎； 当样品制备遇到困难时，对结果几乎没有信心。

1.1 This practice covers a standard procedure for use in preparing the analytical solution required for the analysis of solid, pasty, or powdered vegetable tannin extracts. 1.2 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 The concentration of tannins in solid, pasty, and powdered extracts needs to be reduced to analytical strength for tannin analyses. 4.2 Vegetable tannin extracts are heterogeneous mixtures of components with varying solubility. 4.3 The solubility of such extracts is influenced by temperature and concentration, which affect the degree of dispersion and size of the component particles. 4.4 Since extracts have greater solubility in hot water than cold, it is desirable to dissolve and disperse an extract in hot water and then let the solution cool slowly to standard room temperature. 4.5 It is often difficult to reduce samples of solid and particularly pasty extracts to specimen size and at the same time ensure representative sampling. Therefore, caution is advised in drawing conclusions on the precision and bias of the results obtained on such extracts; where difficulties in sample preparation are experienced, little confidence can be placed in the results.