A disposal system for spent nuclear fuel mainly divides into two parts; Engineered barriers include spent nuclear fuel, canister, buffer and backfill and natural barriers mean a host rock surrounding engineered barriers. If radionuclides released from a repository, they can migrate to the ecosystem. Sorption plays an important role in retarding the migration of released radionuclides. Hence, the safety assessment for the disposal of a spent nuclear fuel should consider the migration and retardation of radionuclides in geosphere. Distribution coefficient is one of input parameters for the safety assessment. In this work, distribution coefficients for crystalline rock as a natural barrier were collected and evaluated for the purpose of safety assessment for the deep geological disposal of a spent nuclear fuel. The radionuclides considered in this work are as follows; alkali and alkaline earth metals (Cs, Sr, Ba), lanthanides (Sm), actinides (Ac, Am, Cm, Np, Pa, Pu, Th U), transition elements (Nb, Ni, Pd, Tc, Zr), and others (C, Cl, I, Rn, Se, Sn). The sorption of radionuclides is influenced by various geochemical conditions such as pH/carbonates, redox potential, ionic strength, radionuclide concentration, kinds and amounts of minerals, and microbes. For the evaluation of distribution coefficients, the data from Sweden (SKB), Finland (Posiva), Switzerland (Nagra), and Japan (JAEA) were collected, analyzed, and the recommended distribution coefficients have been suggested.

A disposal system for spent nuclear fuel divides into two parts; (1) engineered barriers including spent nuclear fuel, canister, buffer and backfill, (2) natural barriers surrounding engineered barriers. Sorption and diffusion are main retardation mechanisms for the migration of released radionuclides. We analyzed the sorption properties of radionuclides for bentonite as a buffer material and collected/ evaluated the distribution coefficients for the purpose of safety assessment for the deep geological disposal of a spent nuclear fuel. Through this, we presented recommended distribution coefficients for radionuclides required for the safety assessment. This work included the radionuclides as follows; alkali and alkaline earth metals (Cs, Sr, Ba), lanthanides (Sm), actinides (Ac, Am, Cm, Np, Pa, Pu, Th U), transition elements (Nb, Ni, Pd, Tc, Zr), and others (C, Cl, I, Rn, Se, Sn). The sorption of radionuclides affected various geochemical conditions such as pH/carbonates, redox potential, ionic strength, radionuclide concentration, kinds and amounts of minerals, and microbes. Among the evaluated radionuclides, Cs, Ni, Pd, and Ra is sensitive to the ionic strength, while Np, Pu, U, Se, and, Tc is sensitive to the redox condition. For the evaluation of distribution coefficients, the data from Sweden (SKB), Finland (Posiva), Switzerland (Nagra), and Japan (JAEA) were collected, analyzed, and the recommended distribution coefficients were suggested.

Meat affects color and quality by metabolite concentrations. Meat produces metabolites, and metabolites are caused by a variety of causes. Meat also produces metabolites by oxidation, which is an inevitable chemical process that meat undergoes which is resulting information of various chemical compounds. Thus, the aim of this study was to profiling the change of metabolites of M. longissimus lumborum during the storage at 4°C. Instrumental color measurements were showed decreasing chroma value, redness and yellowness (P<0.05) during storage, while non-significance (P>0.05) changes found in lightness value. Above all, hue angle was highest at 21 d of storage (P<0.05). The lipid and protein oxidation of muscles was measured by TBARS value significantly increased (P<0.05), thiol and carbonyl groups were also increased significantly (P<0.05) during the display. Total 19 of 60 identified compounds appeared to have a significant difference by storage time (P<0.05). Hue angle had a significant correlation with specific metabolites such as carbon disulfide, 3-methyl-1-butanol, 2-ethyl-1-hexanol, lactic acid and palmitic acid (P<0.05). Results of the current study provide the conversion of volatile and non-volatile metabolites and their correlation with oxidative indicators for changes in meat quality during aerobic storage.

The purpose of this study was to investigate the effects of the concentration of seminal plasma in aerobic and anaerobic conditions on the total motility(TM) and the progressive motility(PM) of spermatozoa in long term preservation of cooled equine semen. We also examine the pregnancy rates after artificial insemination using fresh, cooled or frozen semen, and different durations of cooled-preserved equine semen. In the aerobic state of cooledpreserved semen, As the increase of preserved duration to 24h, 48h, 72h, and 96h, TM tended to decrease in each of different concentrations of formalin-containing experimental group, TM tended to decrease regardless of the concentrations of SP. In different concentrations of SP, TM of without seminal plasma(SP W/O) group tended to be higher than that of SP 20%, SP 33% and SP 50%, especially TM of SP W/O group was significantly higher than other groups at 96 h (p<0.05). PM was higher in the groups of SP W/O and SP 20% than in the groups of SP 33% and SP 50% from 24 h to 72 h in cooled-preservation, especially PM of SP W/O group was significantly higher than other groups at 96 h (p<0.05). In the anaerobic condition of cooled-preserved semen, the results of TM and PM at different concentrations of SP were similar to the results in the aerobic condition although there was a difference in the ratio. The pregnancy rates of fresh-cooled, cooled-preserved and frozen semen were 66.3%, 60.7% and 34.5%, respectively, and the pregnancy rate of frozen semen was the lowest. We also found that it is possible to pregnancy after artificial insemination using 72 h cooled-preserved equine semen. There was similar of the pregnancy rates in the different month from April to August.

MTBE and other gasoline additives contained in gasoline are known to be a refractory substance resistant to biodegradation. As a method of removing these substances, a research of method using native microbes of polluted soil was progressed and among these, bio-degradation possibility under aerobic condition was evaluated. All of the experiments were progressed based on batch experiment of lab scale and analyzed by GC-FID using HS-SPME technique. The result of bio-degradation experiment based on MTBE and other additives(ETBE, TAME) was observed below 1 mg/L, which initial concentration were 100 mg/L for each method. And through production of by-product and CO2, partial mineralization was confirmed. Degradation velocity of each additive was promptly represented in the order of TBA>ETBE>MTBE>TAME. Through this study, bio-degradation possibility of native microbes of oil polluted soil, MTBE and other gasoline additives was confirmed and it was considered that the result could be used for basic experiment data in removing oil pollutants of soil.