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Korean citrus fruits (Jinjihyang and Chunggyun) were treated with electron beam (e-beam) at phytosanitary irradiation doses of 0, 0.4, and 1 kGy, and their irradiation status was screened after storage for 0, 10, and 20 days. Because of the inherent limitations of photo-stimulated luminescence (PSL), the first PSL measurement (PSL1) was not sufficient to distinguish the irradiated samples from the non-irradiated controls. The calibrated PSL approach clearly distinguished the e-beam-irradiated samples from the control based on PSL ratio (PSL2/PSL1): > 10, non-irradiated; < 10, irradiated. In addition to PSL, electronic-sensing techniques (E-tongue and E-nose) clearly discriminated the irradiated Jinjihyang and Chunggyun fruits samples from their non-irradiated counterparts based on principal component analysis of taste attributes and volatile patterns. The quantitative analysis of volatile in irradiated citrus fruits showed that limonene was present at the highest concentration among all the volatiles from peels, and significant dose-dependent decreases were observed in both citrus varieties (p < 0.05). Limonene from the irradiated pulps showed a dose-dependent increase on day 0. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen trapping and its interaction with defects in Li2TiO3 and Li2ZrO3 that were irradiated with hydrogen isotopes and exposed to air were investigated using ion beam techniques and photo-stimulated luminescence (PSL) measurements. During irradiation with 10keV H2 +, the incident hydrogen was trapped in Li2TiO3 at the end of its trajectory until the local concentration reached 12.5at.%, whereas an increase in the hydrogen retained in Li2ZrO3 was observed at a considerably greater depth as compared to the projected range. A broad PSL emission with two peaks at around 2.8 and 3.1eV was observed under irradiation of Li2ZrO3 with 5.17eV light. The PSL intensity of the band at 2.8eV showed a remarkable decrease as compared to the peak at 3.1eV upon irradiation with 10keV D2 +. The results of isochronal annealing subsequent to irradiation showed that the recovery of the luminescence intensity in the 2.8eV luminescent centers and release of hydrogen occurred in the same temperature range of 350–450K. In addition, the formation of a Li2CO3 layer at the surface of Li2TiO3 and Li2ZrO3 following exposure to air was subject to the humidity conditions and was considered to play an important role in the dissociation of water vapor and hydrogen trapping beneath the reaction layer in Li2TiO3 and Li2ZrO3. [Copyright &y& Elsevier]

Abstract: A heavy-ion microbeam system for cell irradiation has been developed using an accelerator at Kyoto University. We have successfully developed proton-, carbon-, fluorine- and silicon-beams in order to irradiate a micro-meter sized area with ion counting, especially single ion irradiation. In the heavy-ion microbeam system, an imaging plate (IP) was utilized for beam diagnostics on the irradiation. The IP is widely used for radiography studies in biology. However, there are a few studies on the low linear energy transfer (LET) by single ions, i.e., low-intensity exposure. Thus we have investigated the energy response for the IP, which can be utilized for microbeam diagnostics. [Copyright &y& Elsevier]

Abstract: Photo-stimulated luminescence (PSL) and thermoluminescence (TL) analyses were done to screen or identify irradiation treatment of ostrich, duck, hen and quail eggs. These eggs were gamma-irradiated at 0, 1, 2 and 3 kGy and the eggshells were used for PSL and TL analyses in a powdered form. The PSL results showed that all the non-irradiated control samples had photon counts (PCs) less than the lower threshold value (700counts/60s). Some of the irradiated samples like ostrich and duck, however, showed PCs higher than the upper threshold value (5000counts/60s), and the other irradiated samples were between the lower and upper values (700–5000counts/60s). Photon (PCs) less than the lower threshold value (700 counts/60s). Although the TL glow curves which originated from the calcite mineral present in eggshells, which were confirmed by X-ray diffraction spectroscopy. The intensities of the first glow curves (TL1) obtained from the egg shells were less intense as compared to that of quartz or feldspar that are usually present on the surface of the food as contaminants. The intensity and shape of the first glow curve (TL1) as well as the glow curve ratios (TL1/TL2) based on a normalization step, enabled discrimination between the control and irradiated eggshells by using natural bio-inorganic minerals. [Copyright &y& Elsevier]

Abstract: We report the results from photo-luminescence (PL) measurements on single crystal RbCdF3 doped with up to 1% Mn2+, before and after X-ray and deep UV irradiation. The intensity of the Mn2+ PL emission at 560nm increases with increasing X-ray or UV (<270nm) dose. A broad PL excitation peak centered near 300nm and extending from 280nm to 420nm occurs after irradiation. The PL intensity excited by this broad band is observed to increase with increasing radiation dose, and no significant decrease in the PL intensity is observed after 2weeks. High intensity bleaching in the wavelength range from 280nm to 420nm reduces the PL emission to the original low pre-irradiated level. These observations suggest that RbCdF3:Mn2+ has potential as a dosimeter for X-rays and deep UV wavelengths less than 270nm. We find that the PL intensity systematically increases with increasing Mn2+ concentration and there is no evidence of saturation for up to 1% Mn2+. This indicates that higher sensitivity could occur with even higher concentrations of Mn2+. [Copyright &y& Elsevier]