Experimental carried out on specimens of zinc-oxide powder were described below Ferthermore, the distribution of strain within the crystallite (<ε
L2>
1/2, ε
1=Δ
L/
L) and the crystallite particle sizes were determined by the Stokes-Corrected Fourier Analysis of the X-ray peaks. The specimens were prepared by grinding with a ball mill and a vibration mill equipped with either a stainless steel special steel vessel.
There were 5 peaks in the ESR spectrum : A peak corresponding to the dangling bonds, B″ peak corresponding to the oxigens combined with the dangling bonds, C peak corresponding to unknown chemical species, C′ peak corresponding to the broken bonds formed on the cleavage surface of the crystallite, B′ peak corresponding to the exygens combined with the broken bonds. The C peak existed in the original material, and decrecreased with grinding. As the grinding proceeded the A, B' and B″ peaks increased. These oxygens colud be desorbed by heating to 300°C. The optical absorption increased by grinding and diminished by heating to 500°C would correspond to these oxygens, and that increased by heating to 900°C correspond to F-center. The case of the special steel vessel, when charge were low, the peak B' as well as the peak A was marked, and during the initial stage of grinding remarkable maximum values, foldings, and the steep rise were observed in the strain distribution curves in the vicinity of the surface. In the case of the stainless steel vessel, especially when the charge was low, B′/B″ and the strength of the B peak was less than that of the special steel vessel. The granules of the specimens were more solid with the special steel vessel, while, those with the stainless steel vessel were finer. It was concidered that those differences due to the difference of the catalytic effects of the material consisting of mill in contact with the crystallite surface on combining the oxygens with the broken bonds.
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