自旋浓度是最重要又是最难精确测量的EPR波谱数据之一,常用比较法测量。经典的比较技术要求未知样品和标准样品在完全相同的实验条件下记谱,这实际上很难做到,特别是当更换样品时,常因样品介电损耗的差别带来仪器灵敏度很大变化。一些作者采用固定内标作为仪器灵敏度变化的指示,以消除仪器因素带来的误差,但仅适用于固定内标与未知或标准样品信号不重叠的场合。本文详细地讨论这种定量方法,并进行若干改进,提出了一套固定内标系列和工作标准系列,并配以相应的实验程序,可以满足各种样品测量的需要。实验表明:这种定量方法有较好的再现性和准确度。文中还引进等效自旋数的概念,并建议用为比较不同类型样品信号强度的统一单位,同时列出由等效自旋浓度计算顺磁离子重量百分数的公式。最后提出相对饱和特性参数Sx的定义并用 Spin concentration is one of the most important and most difficult to accurately measure EPR spectral data and is commonly measured using comparative methods. Classical comparison techniques require that unknown and standard samples be recorded under exactly the same experimental conditions, which is practically difficult to achieve, especially when the sample is changed, often resulting in a significant change in instrument sensitivity due to the difference in dielectric loss of the sample . Some authors use fixed internal standards as an indication of changes in instrument sensitivity to eliminate the error caused by instrumental factors, but only for applications where fixed internal standards do not overlap with unknown or standard sample signals. This paper discussed in detail the quantitative method, and made some improvements, put forward a set of fixed internal standard series and working standard series, together with the corresponding experimental procedures, to meet the needs of a variety of sample measurements. Experiments show that: this quantitative method has better reproducibility and accuracy. The concept of equivalent spin number is also introduced and a uniform unit for comparing the signal intensities of different types of samples is proposed, together with a formula for calculating the weight percentage of paramagnetic ions from the equivalent spin concentration. Finally, the relative saturation characteristic parameter Sx is proposed and used