标准摘要
[中文适用范围]： ISO 6145 的这一部分规定了一种通过注射器将校准组分连续注入补充气流中，从纯气体或其他气体混合物中连续生产包含两种或多种组分的校准气体混合物的方法。 如果使用预混合气体代替纯气体（参见附录 A），可以获得低得多的体积分数。 确定体积分数的体积流量可以根据各个流量计算，并且可以通过 ISO 6145-1 中给出的合适方法独立测量。 该方法的优点在于，可以连续制备大量的气体混合物，并且如果使用适当数量的注射器，或者如果注射器已经准备好，则几乎可以像二元混合物一样容易地制备多组分混合物。 含有已知组成的多组分混合物。 该方法还提供了一种以小步增加混合物中校准组分的体积分数的便捷方法。 因此，它是评估气体分析仪其他特性（例如最小检测限和死区以及精度）的有用方法。 二元混合物（覆盖系数为 2）可获得的体积分数的相对扩展不确定度为 5%，适用范围为 10 至 10。 [外文原描述]： ISO 6145-4:2004 specifies a method for continuous production of calibration gas mixtures, containing two or more components, from pure gases or other gas mixtures by continuous injection of the calibration component(s) into a complementary gas stream by means of a syringe. If pre-mixed gases are used instead of pure gases (see Annex A), much lower volume fractions can be obtained. The volume flow rates, from which the volume fractions are determined, can be calculated from the individual flow rates and can be independently measured by a suitable method given in ISO 6145-1. The merits of the method are that a substantial quantity of the gas mixture can be prepared on a continuous basis and that multi-component mixtures can be prepared almost as readily as binary mixtures if the appropriate number of syringes is utilized, or if the syringe already contains a multi-component mixture of known composition. This method also provides a convenient means for increasing the volume fraction of the calibration component in the mixture in small steps. It is therefore a useful method for evaluation of other characteristics of gas analysers, such as minimum detection limit and dead zone, as well as accuracy. The relative expanded uncertainty in the volume fraction obtainable for a binary mixture (at a coverage factor of 2) is 5 % and the range of applicability is 10 -5 to 10 -2 .
英文名称Gas analysis — Preparation of calibration gas mixtures using dynamic volumetric methods — Part 4: Continuous syringe injection method