重水浓度与吸光度关系曲线类型研究

重水作为反应堆的慢化材料，其浓度直接影响反应堆的安全和性能。为研究其重水浓度与吸光度间的关系曲线类型，基于朗伯-比尔定律，从理论上推导出液态重水中某种水分子的红外吸收峰分别与0~2种其他水分子的红外吸收峰发生重叠时重水浓度与吸光度间的关系式，分情况对二者之间的关系曲线类型进行讨论。采用傅里叶变换红外光谱仪，测得浓度为0.015%~99.98%（摩尔比）的重水标准样品吸收光谱，对重水浓度和吸光度间的关系曲线类型进行验证，理论推导与实际吻合。研究表明，一般情况下，宽浓度范围内，重水浓度与吸光度间的关系曲线类型为二次曲线；窄浓度范围内，关系曲线类型为线性。特殊情况下，吸光度为定值或关系曲线类型为线性。

Research on Type of Relationship Curve between Heavy Water Concentration and Absorbance

Heavy water can be used as moderator material of a nuclear reactor. The concentration of heavy water affects the safety and property of the reactor directly. This work was carried out in order to research the type of relationship curve between heavy water concentration and absorbance. Based on Lambert Beer’s law, the formulas between heavy water concentration and absorbance were theoretically derived respectively when the absorption peak of a certain kind of water molecules in liquid heavy water overlaps with the absorption peak of zero to two other kinds of water molecules. The types of relationship curve between heavy water concentration and absorbance were discussed in different cases. The absorption spectra of heavy water in the concentration range from 0.015% to 99.98% (mol vs mol) were recorded by fourier transform infrared spectrometer and the types of relationship curve were analyzed. It showed that the theory tallied with the practice. The type of relationship curve between heavy water concentration and absorbance was quadratic curved in a wide concentration range and linear when the concentration range was narrow. In special cases, the absorbance was fixed or the type of relationship curve was linear.