Recently, the nuclear decommissioning and environmental restoration industries has significantly attracted as a new industry field due to the decision to decommission the KORI#1 and WOLSONG #1 nuclear power plant. In order to dispose of the decommissioning radioactive wastes generated during nuclear decommissioning, proper analysis is required, and disposal decisions are determined based on the analysis results. When dismantling a nuclear power plant, a few thousand of tons decommissioning waste are produced, so these require analysis for proper disposal. Therefore, a radionuclide facility for decommissioning waste analysis is essential for the disposal of the large quantities of decommissioning waste generated during nuclear power plant decommissioning. Korea Research Institute of Decommissioning (KRID) was established radionuclide analysis facilities to address above issues and support nuclear power plant decommissioning projects. The plan is to perform classification by type and radionuclide for all waste produced during nuclear power plant decommissioning and to support the disposal of radioactive wastes. In addition, we plan to establish validation methods for samples where verification methods are not established, in order to conduct efficient analysis and management. In this presentation, we will introduce the radionuclide facility currently under construction at KRID and present the space design, equipment layout, and utilization plans.

Support for nuclear power plant (NPP) dismantling & decommissioing (D&D) industry is necessary through development of the infrastructure and the D&D technology. Because KORI#1 and Wolsong#1 is planned to decommission until around 2030. Korea research institute of decommissioing (KRID) was established through the preliminary feasibility study. KRID has plan to support nuclear companies to join D&D industry. Normal facilities (Lv.1) of KRID infracstucture are currently being constructed and radiation management facilities (Lv.2) construction is expected to begin in October. Further, KRID is planning the construction of equipment to develop the procedure for radionuclide analysis through R&D project. A total period of the R&D project is 45 months, and the total R&D funding for this period is 19.4 billion won. The ultimate goal of the R&D project is to build the infractstucture base to analyze decommissioning radioactive wastes. Furthermore, the R&D project is important to reliably perform the NPP D&D.

The effects of light intensity and external sucrose on the vase life of cut roses were estimated by monitoring the net photosynthesis and chlorophyll fluorescence. Cut flowers were held under different light intensities 10 (L10) or 50 (L50) μmol‧m-2‧s-1 with or without treatment with external sucrose. We found substantial differences in stomatal conductance, photosynthesis rate, photosystem II (PSII) quantum efficiencies, specific fluxes, and vase life of the cut flowers when exposed to different light intensities. Light intensity at 50 μmol‧m-2‧s-1 increased photosynthesis capacity, thus delaying petal senescence and extending the vase life of cut flowers. L50 flowers maintained a high photosynthetic rate by reducing heat dissipation (DI0/RC) and increasing electron transport (ET0/TR0 and ET0/ABS) in the electron transport chain of the photosynthesis apparatus. The application of external sucrose extended the vase life of cut flowers by improving water balance and sustaining turgor pressure in the petals of the cut flowers. The net rate of photosynthesis of the cut flowers was increased by higher light intensity; however, it was not affected by the application of external sucrose. Our results indicate that the application of external sucrose is necessary to improve the longevity of cut flowers when endogenous sucrose production by photosynthesis is insufficient under low light conditions during the postharvest period. In addition, our results revealed that most of the photosynthetic parameters were significantly correlated with the vase life of cut rose flowers. Moreover, the relation between the rate of photosynthesis and chlorophyll fluorescence parameters indicates that the rise from the basic dark-adapted fluorescence yield to the maximum (OJIP transient) method can be used as a tool for the evaluation and prediction of the photosynthesis rate in cut flowers.

Cardiovascular disease remains as one of the most common causes of high morbidity and mortality worldwide, despite remarkable medical advances in recent decades. Non-invasive techniques play a preeminent role in prevention of cardiovascular disease by diagnosing it at an early stage and guiding optimal patient management. Nuclear imaging is one of the most powerful means available for noninvasive diagnosis and management of poorly perfused myocardial region resulting from the cardiovascular disease. Several radionuclides are available for monitoring blood flow to cardiac tissue. The most validated radionuclides for these measurements are 13N, 15O, 99mTc, 201Tl and 82Rb. Each of 13N, 15O and 201Tl require the presence of an on-site cyclotron, whereas, 82Rb and 99mTc require only a generator. Rubidium (Rb) is an alkali metal ion that acts biologically like potassium and accumulates in cardiac muscle tissue. Rb has a rapid blood clearance profile which allows the use of 82Rb. It also has an ultra-short physical half-life of 75 sec for non-invasive evaluation of regional cardiac blood flow. There are several advantages of 82Rb over other radionuclides. Having a short half-life significantly reduces the radiation dose to the patient. In addition, 82Rb is a positron emitter, which gives the full advantages of PET such as image quantification with superior sensitivity. Several reports have shown superior diagnostic performances of 82Rb-PET over conventional 99mTc-SPECT. 82Rb can be produced from a generator system by the decay of its 25.6-day half-life parent 82Sr. However, the 82Sr parent is difficult to prepare. In routine generator production, certain purity is required to meet the specification of the product. Since there has been no the use of 82Rb radionuclide for research or medical purpose in Korea, we have plans to produce 82Sr with certain purity and develop a 82Sr/82Rb generator system. These studies can also be applied to remove radioactive Sr from radioactive waste waters. Because ion exchange resin, used for purification of 82Sr from impurities, is also utilized to trap radioactive Sr2+ ions from radioactive waste water. After Fukushima Daiichi nuclear accident, interest in the treatment of radioactive waste water has surged. As one of main fission products of nuclear reactor, 90Sr has been regarded as a hazardous radionuclide with half-life of about 29 years. Therefore, the investigation on ion exchange resin is important for removal of 90Sr from radioactive waste water. Here, we optimized 82Sr purification method using ion exchange resin to establish the most suitable procedure.

식품 중 곰팡이 이물에 대한 연구를 위하여 식품 제조 및 유통/보관현장에서의 곰팡이 오염수준 및 주요 곰팡이류를 조사하였다. 측정은 식품유형별 총 9장소 (젓갈류, 식초류, 쌀류, 밀가루류, 냉동만두류, 면류, 과자류, 육가공류, 김치류)와 유통/보관현장 총 8장소(물류 창고)에서 진행하였고, 각 생산라인에서 부유곰팡이, 표면 곰팡이 오염도를 조사하였다. 측정결과, 육가공류 생산현장에서 부유곰팡이 오염도가 가장 높게 측정되었으며, 김치류 생산현장에서의 부유곰팡이 오염도가 가장 낮게 측정되었다. 설비 및 벽면에서의 표면 곰팡이 오염도의 경우, 식품 제조 및 유통/보관 현장에 관계없이 거의 검출되지 않았다. 현장에서 검출된 주요곰팡이를 조사한 결과, Penicillium sp., Aspergillus sp., Cladosporium sp., 종이 우점종 곰팡이로 조사되었다.

In this study, magnetite (Fe3O4) nanoparticles were electrochemically synthesized in an aqueous electrolyte at a given potential of -1.3 V for 180 s. Scanning electron microscopy revealed that dendrite-like Fe3O4 nanoparticles with a mean size of < 80 nm were electrodeposited on a glassy carbon electrode (GCE). The Fe3O4/GCE was utilized for sensing chloramphenicol (CAP) by cyclic voltammetry and square wave voltammetry. A reduction peak of CAP at the Fe3O4/GCE was observed at 0.62 V, whereas the uncoated GCE exhibited a very small response compared to that of the Fe3O4/GCE. The electrocatalytic ability of Fe3O4 was mainly attributed to the formation of Fe(VI) during the anodic scan, and its reduction to Fe(III) on the cathodic scan facilitated the sensing of CAP. The effects of pH and scan rate were measured to determine the optimum conditions at which the Fe3O4/GCE exhibited the highest sensitivity with a lower detection limit. The reduction current for CAP was proportional to its concentration under optimized conditions in a range of 0.09-47 μM with a correlation coefficient of 0.9919 and a limit of detection of 0.09 μM (S/N=3). Moreover, the fabricated sensor exhibited anti-interference ability towards 4-nitrophenol, thiamphenicol, and 4-nitrobenzamide. The developed electrochemical sensor is a cost effective, reliable, and straightforward approach for the electrochemical determination of CAP in real time applications.