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L X-ray spectra of iodine and antimony compounds were measured using a doublecrystal spectrometer, LΥ4 X-rays emitted from the valence 5p electrons were found to be sensitive to the chemical environment. The LΥ4/Lβ3, LΥ1/LΥ1 and Lβ2,15/Lα1 intensity ratios were remarkably changed in various compounds of these elements. LΥ4 energies of iodine compounds were shifted with the increase of the formal oxidation number.

Si K x-ray spectra in SiO 2- Na 2 O were measured with a double-crystal spectrometer. Remarkable change of peak energy, FWHM and intensity were found, depending on sodium contents. Theoretical spectra of Si K β x-ray were calculated to explain the change of x-ray intensity.

It was revealed that by high resolution x-ray measurements that the L γ1 spectra of metallic Nb and Nb-Ni amorphous alloys showed only one broad peak, while those of NbC and NbN had two components. The reason why the amorphous alloys had FWHM’s broader than that in Nb metal was explained by the formation of a mixed band from Nb-4d and Ni-3d electrons. Proton excitation of Nb metal and alloys resulted a smaller L γ1/ L β1 intensity ratio compared to electron or x-ray excitation. Possible interpretation of this difference has been proposed.

The Bi-based oxide superconducting wire is one of the most promising materials for practical uses such as electric power transmission, electromagnets and so on. For the higher performances required in these applications, it is necessary to increase the critical current (Ic). We have carried out synchrotron radiation X-ray diffraction analysis to improve our manufacturing processes and thus to achieve higher Ic. We have performed in situ X-ray diffraction measurements during the sintering and cooling processes, and observed the decrease of Bi-2223(=(Bi,Pb)2Sr2Ca2Cu3Ox) phase during the cooling process. We have also evaluated the distribution of the crystal orientation in whole wire thickness, by measuring the rocking curves. We have observed that the distribution of the crystal orientation is improved by a refinement of the process conditions.

Various aspects of chemical effects on X-ray spectra such as energy shift, emission probability change, satellite formation and peak profile change are reviewed in recent studies. Applicability of the chemical effect to analysis of practical samples is also discussed. Though the emphasis is laid on PIXE, other X-ray production techniques are also taken into consideration because new trends of X-ray production and measurement are growing.

The high performances of Dynamically Innovative BSCCO (DI‐BSCCO) wire have been reviewed. Critical current (Ic) has reached 210 A (77 K and self‐field), which is equivalent 500 A per 10 mm width, by total optimization of whole manufacturing process including Controlled Over Pressure (CT‐OP) sintering. The further higher Ic value will be available on preferable oxide filaments with the improved c‐axis orientation of Bi2223 grains, the minimized non‐superconducting phases, and so on. The Ic of long length wires has been reached 203 A of 42 m 180 A of 1,400 m. Ic in the magnetic field at low temperature has showed great improvements in comparison with the past 150 A class wire. The mechanical performances has been improved due to the densification of the Bi2223 filaments up to 100% by CT‐OP process, moreover have been dynamically improved by reinforcement with stainless steel tapes or brass tapes. These results can enable DI‐BSCCO wire to be applied for the cryogenic applications such as motors, magnets, cables and so on.The high performances of Dynamically Innovative BSCCO (DI‐BSCCO) wire have been reviewed. Critical current (Ic) has reached 210 A (77 K and self‐field), which is equivalent 500 A per 10 mm width, by total optimization of whole manufacturing process including Controlled Over Pressure (CT‐OP) sintering. The further higher Ic value will be available on preferable oxide filaments with the improved c‐axis orientation of Bi2223 grains, the minimized non‐superconducting phases, and so on. The Ic of long length wires has been reached 203 A of 42 m 180 A of 1,400 m. Ic in the magnetic field at low temperature has showed great improvements in comparison with the past 150 A class wire. The mechanical performances has been improved due to the densification of the Bi2223 filaments up to 100% by CT‐OP process, moreover have been dynamically improved by reinforcement with stainless steel tapes or brass tapes. These results can enable DI‐BSCCO wire to be applied for the cryogenic applications such as motors, magnets, cab...

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds were studied by electron and proton bombardments. L γ1 X-rays which involve transition of 4d electrons of the valence shell were found to be sensitive to the chemical environment. The L γ1 /L β1 X-ray intensity ratio increased with an increase of the 4d electron occupation of niobium or molybdenum in niobium or molybdenum compounds, showing that the chemical effects can be ascribed to the 4d electron behavior of the metallic atom in its compounds.

Local structure of Er/sup 3+/ in the Er-doped optical fiber (EDF) was explored by the X-ray absorption fine structure (XAFS) measurement. We have successfully observed variations of Er-O coordination number and Er-O distance by changing the Al concentration.