A novel analysis approach using atomic fluorescence excited by synchrotron radiation is presented. A system for synchrotron radiation-atomic fluorescence spectrometry is developed, and experimental conditions such as flow rate, analyte acidity, concentration of pre-reducing and hydrogenation system are optimized. The proposed method is successfully applied to get an excitation spectrum of arsenic. Seven of ten primary spectral lines, four of which have never been reported by means of atomic fluorescence spectrometry, agree well with the existing reports. The other three are proposed for the first time. Excitation potentials and possible transitions are investigated. Especially for the prominent line at 234.99 nm, the mechanism of generation is discussed and a model of energy transition processes is proposed.
Compared with the traditional thin film techniques, the matrix-assisted pulsed laser evaporation (MAPLE) technique has many advantages in the deposition of polymer and organic thin films. It has a wide range of applications in many fields, such as non-linear optics, luminescent devices, electronics, various sensors. We have successfully deposited polyimide thin films by using the MAPLE technique. These films were characterized with XPS. The XPS spectra showed that the single-photon effect is ob-vious at low laser fluence and the chemical bonds will be broken, resulting in decomposition of the films. Contrarily, the single-photon effect will decrease and the multi-photon effect and the photothermal effect will increase at high laser fluence, resulting in the protection of the structure of the polyimide thin films and the obvious decrease in decomposition. High laser fluence is more suitable for the deposition of polymer and organic thin films than low laser fluence.
