26.08.2015   Nuclear Back-end and Transmutation Technology for Waste Disposal

10.2.1.1 Ultraviolet

Ultraviolet irradiates TiO2 by using a commercial UV lamp. Irradiation intensity is measured by an ultraviolet meter and is controlled by changing the distance between the lamp and the sample. The intensity is varied at a range from 0.01

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Fig. 10.1 Water droplets on the TiO2 surface before and after ultraviolet irradiation. (a) Before ultraviolet irradiation. (b) After ultraviolet irradiation with 1 mW/cm2 for 1 h

to 5 mW/cm2. The center wavelength of the ultraviolet from this lamp is 365 nm. Figure 10.1 shows a typical irradiation effect on surface wettability change before and after ultraviolet irradiation.

10.2.1.2 Gamma Rays (y-Rays)

The 60Co Y-ray irradiation facility in the Research Reactor Institute, Kyoto Univer­sity, is utilized for y-ray irradiation. The integrated irradiation dose is estimated by an irradiation time and a distance from the Y-ray source. The Y-ray energy of this facility is about 1 MeV (1.17 and 1.33 MeV) and the maximum dose rate is about 15 kGy/h.

10.2.1.3 Proton Beam

The FFAG (fixed-field alternating gradient) accelerator in the Research Reactor Institute, Kyoto University, is utilized for proton-beam irradiation. The energy of the proton beam is set at about 100 or 150 MeV. The maximum beam current of this facility is about 10 nA.