In some countries, extended storage may encompass a timeframe of the order of centuries. Initially conceived to last only a few decades (40 years in Germany), extended storage periods have now to be considered for spent nuclear fuel due to the expanding timeline for the definition and implementation of the disposal in geologic repository. The corium's nominal, composition of (U 0.5Zr 0.5) O 2 also corresponded to its observed single phase microstructure. The lattice parameter of a = 5.2984 Aa was considerably reduced compared with pure, stoichiometric UO 2 and was consistent with a lattice containing, approximately 45 mol% ZrO 2 that had undergone little oxidation. X-ray diffraction of the corium pool disclosed a deformed cubic fluorite lattice of UO 2. EPMA oxygen measurements revealed in the upper part of the bundle a super stoichiometry of x = 0.3-0.4 in UO 2+x ' indicating that fuel fragments in this position had undergone considerable oxidation. Electron microprobe analysis line scans across the cladding-fuel interface showed interdiffusion of U and Zr, with U diffusing down the grain boundaries of the oxidized cladding, while point analyses revealed noticeable amounts of Zr (1.5-4.2 wt%) in the UO 2 fuel. The fuel samples from the upper bundle and cavity edge were porous and had remnants of thick oxidized cladding adhering to them. Metallographic and microprobe analysis of the degraded fuel pieces were carried out. The degraded fuel rod bundle from the second Phebus test (FPT1) was examined at ITU, Karlsruhe. The results showed increased soil DTPA extractable heavy metal concentrations reflecting high soil pollution, statistically significant decrease of the beet dry matter (dm) yield, but increase of the metal at the beets dm, the nitrogen concentrations, and consequently, significant contribution to the increase of beet crude protein yield. The study was carried out in a greenhouse pot experiment, including 12 treatments of heavy metals mixtures composed of Zn, Mn, Cd, Co, Cu, Cr, Ni, and Pb, with each metal at 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22 mg kg-1 respectively. The purpose of the present work was to study the effect of treated wastewater and soil enrichment with heavy metals on the growth of Beta vulgaris L., on beet quality, expressed in terms of dry matter heavy metal, nitrogen and crude protein content. As heavy metals are toxic and at higher levels pose a health risk, it is necessary to study their quantitative changes of their presence. However, the quantitative effects of heavy metals on plant proteins under the presence of heavy metals and their effects on these vital compounds of plants have not been studied adequately. The heavy metal pollutants on plants formation, the accumulation and the mechanisms of establishing tolerance have been studied in detail by scientists. The concentration and sizes of defects involved and their possible relation to the rim structure formation are discussed The observed behaviour can be equally explained by a saturation of single interstitials with subsequent recombination with excess vacancies, as by the saturation and enlargement of dislocation loops. In terms of local burn-ups, the lattice contraction followed the rate of the matrix Xe depletion measured by EMPA, exceeding greatly the contraction rate due to dissolved fission products. This lattice contraction coincided with other property changes in the rim region, i.e., porosity increase, hardness decrease and Xe depletion. The results showed a significant but constant peak broadening, and a lattice parameter that increased towards the pellet edge and decreased again within the rim-zone. Radial variations of the lattice parameter and peak width of two high burn-up UO 2-fuels (67 and 80 GWd/tM) were measured by a specially developed micro-X-ray diffraction technique, allowing spectra acquisition with 30 μm spatial resolution.
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