纵向交流磁场塞曼原子吸收光谱仪的研制

A Zeeman Atomic Absorption Spectrometer With Longitudinal A. C. Modulated magnetic field.

研制了一种采用50Hz半波调制的纵向交流磁场塞曼原子吸收光谱仪,自行设计的一个16mm长的横向加热石墨炉,置于22mm宽的磁铁气隙中,电磁铁的磁感应强度可在0～1.0T范围连续可调,在0.8T时消耗功率为2.7kVA。当在一中间和最大磁场下测量时分析曲线的动态范围可扩展10倍。本仪器采用了一台PC/AT微机作实时数据处理和部分自动控制。实验结果表明本仪器可校正吸光度高达2.0的背景吸收。测试了13个元素的特征量、相对灵敏度比和最大吸光度值,其峰值特征量与一般石墨炉相近,16mm的横向加热炉的峰面积特征量与28mm的massman石墨炉相比约高2.25倍。

A Zeeman atomic absorption spectrometer has been constructed with a 50Hz semi-wave modulated longitudinal magnetic field. A 16mm transversely heated graphite furnace is operated in the magnetic gap 22mm in breadth. The magnetic field strength is adjustable from zero to 1.0 T. The power consumption is 2. 7kVA at 0.8T. The dynamic range of the analytical curve can be extended 10 times when the intensity measurements are performed at two different field strengths. i. e. intermediate and max-imum field strength, rather that at zero and maximum strength. This spectrometer is provided with a PC/AT computer for real time data processing and some autocontrols. Experimental results show that the Zeeman instument is capable of correcting background absorption up to absorbance 2.0. The peak characteristic mass data obtained by the transversely heated graphite furnace are similar to those by a conventional furnace, but the area characteristic mass data obtained by transversely heated graphite furnace in a 16mm of tube is about 2.25 times higher than those by the Massman graphite furnace with a 28mm of tube.