According to Article 4 and 5 of the Nuclear Safety and Security Commission (NSSC) Notice No. 2020-6, radioactive waste packages should be classified by radioactive levels, and finally permanently shipped to underground or surface disposal facilities. The level of the radioactive waste package is determined based on the concentrations of the radionuclides suggested in Article 8 of NSSC Notice No. 2021-26. Since most of the radionuclides in radioactive wastes are beta nuclides, chemical separation and quantification of the target nuclides are essential. Conventional methods to classify chemically non-volatile radionuclides such as Tc-99, Sr-90, Nb- 94, Fe-55 take a lot of time (about 5 days) and have low efficiency. An automated non-volatile nuclide analysis system based on the continuous chemical separation method of radionuclides has been developed to compensate for this disadvantages of the conventional method in this study. The features of the automated non-volatile nuclide separation system are as follows. First, the amount of secondary waste generated during the chemical separation process is very small. That is, by adopting an open-bed resin column method instead of a closed-bed resin column method, additional fittings and connector are unnecessary during the chemical separation. In addition, because the peristaltic pump is supplied for the sample and solution respectively, it is great effective to prevent cross-contamination between radioactive samples and the acid stock solution for analysis. Second, the factors that may affect results, such as solution amount, operating time and flow rate, are almost constant. By mechanically controlling the flow rate precisely, the operating time and additional factors required during the separation process can be adjusted and predicted in advance, and the uncertainty of the chemical separation process can be significantly reduced. Finally, it is highly usable not only in the continuous separation process but also in the individual separation process. It can be applied to the individual separation process because the user can set the individual sequence using the program. As a result of the performance evaluation of the automation system, recovery rates of about 80–90% and reproducibility within 5% were secured for all of the radionuclides. Furthermore, it was confirmed that the actual work time was reduced by more than 50% compared to the previous manual method. (It was confirmed that the operation time required during the separation process was reduced from 6 days to 3 days.) Based on these results, the automation system is expected to improve the safety of workers in radiation exposure, reduce human error, and improve data reliability.

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.

Squid ink was added to the low salt fermented squid by 4% of concentration and ripened at 10˚C for 6 weeks and at 20˚C for 28 days. The effect of the squid ink on the non-volatile organic acids of low salt fermented squid were investigated. The results are as follows; The non-volatile organic acid in the salt fermented squid without addition of the squid ink was examined and the result showed that lactic and acetic acids were the major organic acids even if very small amount of citric and oxalic acids were detected. In the squid ink added to the low salt fermented squid, total quantity of non-volatile organic acid in the latter part of the ripening was lower than no treatment groups.

세라믹 타겟인 Ta2O(sub)5을 장착한 rf-마그네트론 스퍼터를 이용하여 Ta2O(sub)5 완충층을 증착하고, Sr(sub)0.8Bi(sub)2.4Ta2O(sbu)9 용액을 사용하여 MOD 법에 의해 SBT 막을 성장시킨 metal/ferroelectric/insulator/semiconductor (MFIS) 구조인 Pt/SBT/Ta2O(sub)5/Si 구조의 Ta2O(sub)5 완충층 증착시의 O2유량비, Ta2O(sub)5 완충층 두께에 따른 전기적 특성을 조사하였다. 그리고 Ta2O(sub)5 박막의 완충층으로써의 효과를 확인하기 위해 Pt/SBT/Ta2O(sub)5/Si 구조와 Pt/SBT/Si 구조의 전기적 특성을 비교하였다. Ta2O(sub)5 완충층 증착시의 O2유량비가 0%일 때는 전형적인 MFIS 구조의 C-V 특성을 얻지 못하였으며, 20%의 O2유량비일 때 가장 큰 메모리 윈도우 값을 얻었다. 그리고 O2유량비가 40%, 60%로 증가할수록 메모리 윈도우는 감소하였다. Ta2O(sub)5 완충층의 두께의 변화에 대한 C-V 특성에서는 36nm의 Ta2O(sub)5 두께에서 가장 큰 메모리 값을 얻었다. Pt/SBT/Si 구조의 메모리 윈도우 값과 누설전류 특성은 Pt/SBT/Ta2O(sub)5/Si 구조의 값에 비해 크게 떨어졌으며, 따라서 Ta2O(sub)5 막이 우수한 완충층으로써의 역할을 함을 알았다.

Indirect CO2 effect due to non-methane volatile organic compound (NMVOC) emissions from solvent and product use and fugitive NMVOC emissions from fuels in the Republic of Korea and 13 Annex I countries under United Nations Framework on Climate Change were estimated and the proportions of them to total greenhouse gas (GHG) emissions ranged from 0.092% to 0.45% in 2006. Indirect greenhouse effect (CO2, CH4, and O3) were estimated at 13 photochemical assessment monitoring sites in the Republic of Korea using concentrations of 8 NMVOCs of which indirect global warming potential (GWP) were available. The contribution of toluene to mixing ratio was highest at 11 sites and however, the contribution of toluene to indirect greenhouse effect was highest at nine sites. In contrast to toluene, the contributions of ethane, butane, and ethylene were enhanced. The indirect greenhouse effects of ethane and propane, of which ozone formation potentials are the lowest and the third lowest respectively among targeted 10 NMVOCs, ranked first and fourth highest respectively. Acetaldehyde has relatively higher maximum incremental reactivity and is classified as probable human carcinogen however, its indirect GWP ranked second lowest.