우수한 알카리성 식품이자 발효식품인 오이김치를 직접 제조하여 저장기간별로 글로로필, 비타민 C의 함량의 변화를 측정하고 관능검사를 실시하여 오이김치의 저장기간별 선호도를 조사하였다. 클로로필은 클로로필 a의 경우 저장 0일 52.21%, 저장 11일 20.67%, 저장 14일은 분포를 보이지 않았고 클로로필 b의 경우는 저장 0일 14.44%, 저장 11일 16.99%. 저장 14일까지는 클로로필 a와 마찬가지로 분포를 나타내지 않았다. 반면에 Phephorbide a의 경우는 저장 0일 28.44%. 저장 5일 31.20%. 저장 11일 42.63%로 증가하였으나, 저장 12일에서 14일까지는 분포하지 않았다. Phephorbide b의 경우는 저장 0일 1.25%,저장 1일 10.55%, 저장 11일 15.79%로 증가하였으며 저장 12일에서 14일까지는 분포하지 않았다. Pheophytin a의 경우는 서장 0일 2.85%, 저장 11일 3.92%, 저장 12일에서 14일까지는 소실되었고, Pheophytin b는 저장 0일 0.62%, 저장 5일 1.71%로 증가하다가 저장 11일에서 14일은 분포하지 않았다. 비타민 C는 저장 0일 2.57(mg/100g), 저장 4일 5.49(mg/100g)으로 증가, 저장 11일 2.95(mg/100g)으로 감소, 저장 14일에는 소실되었다. 관능평가는 외관, 냄새, 맛, 질감, 종합적인 맛에서 유의미한 차이를 보였는데, 저장 8일에서 가장 높은 선호도를 나타내었고, 저장 10일부터는 낮은 선호도를 보였다.
Recent discovery of an Io-related feature in Jupiter's auroral regions prompted us to search for an or multiplet at 1304Å in IUE aurora spectra. In three independent IUE spectra taken on January 18, 1981, we found an emission structure at 1304Å , with a signal-to-noise of about three. If the structure is due to the OI emission, then it is a direct evidence of oxygen ion precipitation, which may originate from Io and Io torus. The emission rates of the H2 H2 band systems and the or multiplet are about 50 kR and 150 R, respectively. We have constructed high resolution model spectra with the estimated emission rates of H2 H2 , OI and SI for the Goddard High Resolution Spectrograph (GHRS) onboard the Hubble Space Telescope. The model spectra clearly show the or and SI mulitplets separated from crowded H2 H2 Lyman and Werner band lines, and therefore it is promising to detect the OI and SI multiplets with the GHRS. Given the possibility that the lo-related feature may be caused by ion precipitations from the Io flux tube, it is likely that the OI emission may be detected in the footprint area of the IO flux tube.
Practical disposal of transformer insulation oil laden with PCBs (polychlorinated biphenyls) by a chemical treatment has been studied in field work. The transformer insulation oil containing PCBs was treated by the required amounts of PEG (polyethylene glycol) and KOH, along with different reaction conditions such as temperatures and times. The reaction of PEG with PCBs under basic condition produces arylpolyglycols, the products of nucleophilic aromatic substitution. Removal efficiencies of PCBs in insulation oil before and after chemical treatment were examined.
The removal efficiency of PCBs was very low at lower temperatures of 25 and 50℃. Under the reaction condition of PEG 600/KOH/100℃/2hr, removal efficiency of PCBs was approximately 70%, showing completely removal of PCBs containing 7~9 chlorines on biphenyl frame which appear later than PCB IUPAC Number 183 (2,2',3,4,4',5',6-heptaCB) in retention time of GC/ECD. However, when increasing the reaction temperature and time to 150℃ and 4 hours, removal efficiency of PCBs reached 99.99% without any formation of PCDDS/PCDFs during the process. Such reaction conditions were verified by several official analytical institutions. In studying the reaction of PEG with PCBs, it confirmed that the process of chemical treatment led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.