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Sc (0, 1, 2, 3 mol%): Tm: LiNbO₃ crystals were prepared by the Czochralski method. The inductively coupled plasma-atomic emission spectrometry (ICP-AES) analysis test shows that, as the concentration of Sc${}^{3+}$ increases, the effective segregation coefficient of Sc${}^{3+}$ and Tm${}^{3+}$ decreases. The X-ray diffraction (XRD) analysis test shows that the lattice size increases first and then decreases. The optical homogeneity analysis test shows that the birefringence gradient of the Sc-3 sample is $4.7\times 10^{-}5$$\mathrm{\Delta }$R/cm${}^{-1}$, which is 1/3 of pure LiNbO₃. Research demonstrates that when the Sc${}^{3+}$ content reaches or exceeds the threshold value, ${\mathrm{\text{Nb}}}_{\mathrm{\text{Li}}}^{4+}$ is replaced completely, thus introducing non-intrinsic defects ${\mathrm{\text{Sc}}}_{\mathrm{\text{Li}}}^{2+}$ and ${\mathrm{\text{Sc}}}_{\mathrm{\text{Nb}}}^{2-}$. These defects are able to form ${\mathrm{\text{Sc}}}_{\mathrm{\text{Li}}}^{2+}-{\mathrm{\text{Sc}}}_{\mathrm{\text{Nb}}}^{2-}$ charge self-compensating defect groups, it will greatly increase optical homogeneity.

Trace elements in thick samples of aluminum metal reference standards were analyzed by means of PIXE and ICP-AES. The samples were SRM1258 and SRM1259 from National Institute of Standards and Technology (U.S.A.) and 1-A, 3, 4-A and 83 from Japan light metal association. The observed PIXE spectrum was converted “into that of a hypothetical thin target and it was analyzed using a relative intensity database for thin target. A good agreement was obtained between the certified and the found amount of the trace elements. The analytical results for SRM1258 and SRM1259 obtained by ICP-AES method also agreed well with the present results confirming the analytical accuracy.

PIXE technique was applied to measurement of trace elements in total diet samples collected in Japan for estimation of their daily dietary intake. Results of PIXE analysis were compared with INAA Concentration of Cl, K, Mn and Zn by PIXE analysis well agreed with the results from NAA, while Ca, Fe and Cu showed different results between these two techniques. Preliminary data of elemental concentrations in Mate-cha, a kind of tea popular in South America, determined by ICP-AES indicated a little higher concentration of Cu than that by PIXE and much lower value than that by INAA For Zn. concentrations by PIXE and ICP well agreed to each other, while INAA gave much lower value. Japanese internal radiation doses by ¹³⁷Cs and ⁹⁰Sr were estimated to be 2.30µSv/year and 1.27µSv/year respectively as the effective dose equivalents using the daily intake data obtained for K and Ca.

PIXE technique was applied to the measurement of elements in the placenta, maternal blood and cord blood of human. The elements determined in these samples include Cl, K, Ca, Fe, Cu and Zn. The values obtained by PIXE were compared with those by ICP-AES to test the accuracy of the method. In placental samples, the mean values of K, Fe, Cu and Zn concentrations obtained by the two methods agree, while Ca concentration is lower in PIXE analysis. The values from PIXE, however, show larger variations resulting from inhomogeneity of the placental samples composed of various tissues different in histological functions. In the analysis of blood samples, the results of the two methods agree for Cl, K, Ca, Fe, Cu and Zn, although the standard deviations tend to be larger in PIXE. These results indicate that PIXE is a useful method for the determination of elements in placental and blood samples, although the preparation to homogenize sample is necessary to obtain accurate results.

In order to find the relationships between leaf elements contents and phenomenon of growing weakness of plant, the variation of thirteen mineral elements in pine needles were determined at the period from well growth to weak growth for six consecutive years. Twelve elements consisting toxic metals (Pb, Cr, and Cd) and essential mineral elements (P, K, Fe, Mn, Cu, Zn, Ca, Mg and Na) were analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES), and the N content was analyzed using automatic azotometer (KDY-9820 type). The results showed that there were no significantly variatation in elements N, K, Ca, Mg and Fe between normal and abnormal growing trees. However, the sharply increase of Na and toxic heavy metal Cr, and the gradually decrease of trace elements such as Mn, Cu, Zn, and further the rising of P year by year in pine needles might had much more relationships with the weak growth of Pinus tabulaeformis. The correlations of each element could be used to improve the ratios of different element in order to make plant grow well.

The reasons behind the fracture of the 220kV pipe busbar horizontal line clamp were analyzed. The fracture morphology, composition of chemical elements, metallographic examination and SEM of the fractured clamp were investigated by ICP-AES, SEM and metallurgical microscope. The test results show that many casting defects are found and that this batch of horizontal line clamp is substandard product. The horizontal line clamp structure design is unreasonable, which leads to the stress concentration in the location of the fracture. The corresponding suggestions are proposed.