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The paper presents the verification of home made Position Sensitive Spectrometer (PSS) while using synchrotron radiation light (SRL) as an excitation source. When Cr in the substance of light base was analyzed by the PSS, the lowest detection limit of a few ppm was achieved. Also linear proportionality between the count rate of the PSS and Cr concentration was obtained. This verities the feasibility of trace element analysis with high-energy resolution when using the PSS. At measurement of Cr Kβ₅ band in metallic Cr and its compounds, it was discerned that the intensity of Cr Kβ₅ becomes more intense with increasing oxidation number of Cr compounds. Such a change shows that high-energy resolution analysis using the PSS can make a useful method for the study of chemical states.

The influence of Compton tail background on the PIXE detection limit is discussed in the case of human serum as an example of biological samples containing sodium element. The PIXE spectrum of the human serum for 3 MeV proton bombardment was measured with a Si(Li) x-ray detector and the Compton tail edge of 440keV γ-rays from ²³Na in the serum was observed at the x-ray energy of 278.4 keV. The spectrum of the Compton tail was measured for the 511 keV γ-rays from a ²²Na source and compared with a theoretical one. It is found that the intensity of the experimental Compton tail below 35 keV is two~three times larger than the theoretical one. Minimum detection limits for the elements of Z=35~55 in the human serum were estimated by using experimental Compton tail background.

The paper presents some preliminary results of PSS performances measured by using various exciting sources. The energy resolution of 25eV for MnKα and of ~ 15eV for TiKα is obtained, respectively, for various exciting sources. The satellite structure of SiKα has been clearly observed. The peak of CrKβ and of MnKα in a stainless steel sample has also been resolved and the detectable amount of Ti has been less than 10^-9 g. The comparisons of these results attempt to find more suitable exciting source for a different application of PSS and to discuss the possibility of application carried out by PSS combined with a new μ-X-ray exciting source.

A simple and sensitive method has been developed to measure nicotinic acid using CuGeO₃ nanowire modified glassy carbon electrode (GCE). The CuGeO₃ nanowires can be attached firmly to the surface of the GCE. The modified GCE exhibits good detection performance for nicotinic acid with the correlation coefficient of 0.993 and 0.985 for cvp1 and cvp2, respectively. The detection limit is 9.2 μM and 0.83 μM, respectively at a signal-to-noise ratio of 3 with the linear range of 0.001–2 mM. The CuGeO₃ nanowire modified GCE exhibits good stability and reproducibility.