The decommissioning of a nuclear power plant generates large amounts of radioactive waste, which is of several types. Radioactive concrete powder is classified as low-level waste, which can be disposed of in a landfill. However, its safe disposal in a landfill requires that it be immobilized by solidification using cement. Herein, a safety assessment on the disposal of solidified radioactive concrete powder waste in a conceptual landfill site is performed using RESRAD. Furthermore, sensitivity analyses of certain selected input parameters are conducted to investigate their impact on exposure doses. The exposure doses are estimated, and the relative impact of each pathway on them during the disposal of this waste is assessed. The results of this study can be used to obtain information for designing a landfill site for the safe disposal of low-level radioactive waste generated from the decommissioning of a nuclear power plant.

시설 토마토 과실의 상품성을 향상시키기 위하여 칼륨 엽면처리 농도 및 시기를 분석한 결과, 0.5% 칼륨 엽면처리구에서 과중이 200~400g인 상품과 비율이 75.5%로 대조구에 비해 29.5%증가하였다. 처리시기는 착과기가 가장 좋았는데, 착과기에 0.5% 칼륨를 엽면처리하면 상품과 비율이 대조구에 비해 5.9% 증가하였고 상품수량은 10% 증가하였다.

Background : Ginseng (Panax ginseng C. A. Meyer) is a perennial crop grown for more than 4 years in the same place. Therefore, it is highly affected by soil environment, especially nutrients on soil. This study was carried out to investigate the effects of application levels of nitrogen, phosphate, potassium on growth and soil chemical properties of ginseng. Methods and Results : 0, 1, 4, 8, 16, 32 ㎏/10 a of Urea, fused superphosphate, potassium chloride were each treated at 3.3 ㎡ of the field and ginseng cultivar 'Geumpoong' was transplanted. Growth characteristics were investigated by growth period and soil chemical properties were investigated every 3 months. As the levels of treated nitrogen increased, root weight increased from 0 ㎏/10 a to 4 ㎏/10 a and then decreased. Electrical conductivity (EC) and the NO3 content tended to increase as time goes by. As the levels of treated phosphate increased, the SPAD content increased. Soil analysis of October showed that the NO3 content of phosphate 32 ㎏/10 a treatment increased to 80.25 ㎎/㎏. In the case of potassium 32 ㎏/10 a treatment, the emergence rate was 74% and root weight was 2.06 g, which were the worst in all treatments. When the levels of treated potassium increased, the EC tended to increase gradually and the pH was decreased. Conclusion : These results indicate that the application levels of Nitrogen, phosphate, potassium influence growth of ginseng and soil chemical properties. Further research will be needed to establish appropriate standards of soil chemical properties for ginseng cultivation.

본 논문은 바탕면의 함수조건에 따른 보수재료로서 MKPC의 인발 부착강도, 전단 부착강도, 계면 부착강도를 폴리머 시멘트 모르 타르, 에폭시 모르타르와 비교 분석하였다. 그 결과 MKPC는 PC 및 MKPC와 비교하여 바탕면 함수조건에 따른 부착성능의 변화가 상대적으 로 작은 것으로 나타났다. 또한 MKPC의 경우 절건 바탕면에서의 부착성능은 무기계 보수재료인 폴리머 시멘트 모르타르와 비교하여 우수한 특성을 지니고 있으며, 습윤 바탕면에서의 부착성능은 폴리머 시멘트 모르타르와 유사한 수준을 보이고 있으나 에폭시 모르타르와 비교하여 우수한 특성을 지니는 것으로 나타났다.

To investigate effects on the growth and ginsenosides accumulation in ginseng hairy root, potassium phosphate was supplemented with 1.25, 2.5, and 5.0 mM concentration in 1/2 MS medium, respectively. Potassium phosphate supplement was increased the biomass and ginsenosides accumulation when it was dose at the concentration of 1.25 mM. And the growth rate of hairy root in the light condition was higher than in dark condition. The highest contents and productivity of ginsenosides were observed at the supplement of 1.25 mM potassium phosphate at the 7th day after the culture onset. Ginseng hairy root cultured in 20 L bioreactor supplemented with 1.25 mM KH2PO4 was increased the growth with 1,609 g (F·W) and ginsenosides content with 11.09 mg than those in control.