New emissin spectrometers for multielement analysis with pulse operated plasma source and time-gated detector

设计并制造了一种新的MIP源，该源由几百瓦的短时微波驱动，选择性地发射时间强度的原子线，用于痕量元素分析。使用非冷却腔和不需要重型同轴电力电缆是其显着特点的一部分。为了实现固体材料的直接蒸发和原子蒸气的精确控制，在源上附加了一个时空稳定的火花源。调制MIP和火花原子化器的结合能有效地产生简单而尖锐的原子线光谱，背景信号可忽略不计，有利于高精度的定量元素分析。对脉冲等离子体源时间分辨强度比测量中的线性和动态范围进行了详细的测量和理论分析，并研制了一台以射频脉冲HCL为激发源的时间选通原子荧光光谱仪，用于痕量元素的分析。发现光子计数操作的峰面积检测模式有效地扩展了元素分析的动态范围。

A new MIP source driven with several hundred-watt microwave of short duration, which selectively emitts temporally-intense atomic lines, was designed and constructed for allowing the trace element analysis. The use of non-cooled cavity and no requirement of heavy duty coaxial power cable are part of its notable features. For the direct vaporization of solid materials and precise control of the atom vapor introduction to the source, a tenporally and spacially stable spark source was attached. The combination of the modulated MIP and the spark atomizer was extreamely effective to yield simple and sharp atomic line spectra with a negligibly low back ground signal, facilitating quantitave element analysis with high precision.A miltichannel detection system using a gated silicon intensified target(SIT) vidicon was constructed for dynamic spectrophotometry. The linearity and dynamic range were carefully measured and theoretically analyzed for applications such as time-resolved intensity ratio measurements of pulse operated plasma sources.A new time-gated atomic fluorescence spectrometer with RF pulsed HCL as an excitation source was developed and evaluated for trace element analysis. A peak area detection mode of photon counting operation was found effective to extend the dynamic range of the element analysis.