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The characteristics of a laser-induced shock wave plasma which was induced by focusing a laser pulse on the surface of glass samples were examined by using radiation from a XeCl excimer laser and a TEA CO2 laser under reduced pressure of around 1 Torr. It was observed that shock wave plasma could not be generated by the TEA CO2 laser on low-melting-point glass because of the lack of expulsion from the sample surface. On the other hand, with the use of an excimer laser, shock wave plasma can be generated, even in low-melting-point glasses, thus making it amenable for spectrochemical analysis. Initial quantitative analysis was performed on a number of glass samples, and a linear calibration curve with a slope of near unity was obtained at a certain pressure. Furthermore, light elements such as Li and B, which are usually difficult to observe by the X-ray fluorescence method, were also successfully detected with a very low detection limit of less than 10 ppm. Other detection limits and background equivalent concentrations of almost all elements usually contained in glass, such as Na, Mg, Al, K, Ca, Ti, Zn, Zr, and Ba, were also presented. These results showed that the detection limit is much lower than those usually required for glass analysis.

We present in this report the results of experimental study on the spectrochemical analysis of powder samples using subtarget supported micro mesh (SSMM) sample holder in low pressure ambient gases. The study is substantiated by establishing the analyte excitation mechanism with the evidence of shock wave plasma generation and the high temperature induced subsequently required for the thermal excitation and emission of the ablated atoms. The application of SSMM sample holder using Cu subtarget and stainless steel micro mesh to a number of powder samples in low pressure ambient gases are shown to produce generally sharp emission lines with low background, without suffering from intensity reduction and matrix effect commonly found in the use of pelletized powder samples. The same excellent spectral quality is demonstrated by its application to the analysis of rice samples which is the major staple diets in a large number of countries. In particular the analysis of Zn in rice is shown to exhibit a linear calibration line with extrapolated zero intercept and a detection limit of < 0.87 μg/g which is promising for quantitative analysis.

In this work, the microwave absorption performance of barium hexaferrite multi-nanolayers synthesized by aceramic method was investigated. The microwave absorption performances of BaFe12O19 and BaCoZnFe10O19 multi-nanolayers with thicknesses of 25, 50, 75, 100, 200, 300, 500, and 1000 nm were evaluated using a vector network analyser (VNA) at room temperature to characterize the reflected signal (S11) and transmitted signal (S21) in the frequency range of 7–13 GHz. The microwave absorption performance of the multilayer structure was enhanced due to the combination of nanolayers. The optimal absorption performance was achieved with a reflection loss of less than –30 dB (99.9% absorption) for a layer thicknesses of less than 500 nm.