When disposing of spent nuclear fuel, there is a risk of exposure that could exceed the annual allowable dose due to human intrusion after the institutional control period. Therefore, it can be treated with the pyroprocess, but the decontamination factor is not sufficient, and an additional actinide recovery is required because molten waste salt-containing actinide is generated. In the case of reducing the element in the spent molten salt through an electrochemical method using a liquid Bi electrode, it is difficult to separate only the actinide element because the two-element groups are reduced together due to the large concentration difference between the actinide and the rare earth element. Therefore, a process of forming a Bi intermetallic compound using a liquid Bi electrode, which has higher element separation efficiency than a liquid Cd electrode, and physically separating the Bi intermetallic compound using the difference in density of the produced compound has been proposed. For this, it is necessary to understand the properties and density separation of the intermetallic compound to be produced, and experiments were planned and conducted for this purpose. Various metals were added to the molten Bi to form an intermetallic compound, and an analysis device such as SEM was used to determine the intermetallics distribution, composition, and internal structure. As the added metal, Ce is a representative element for lanthanide, and Hf with the most similar intermetallic density, decomposition temperature, and standard reduction potential to U, and U as a substitute element for actinide was adopted. As a result of SEM and EDS analysis, it was confirmed that the separation was made in Bi due to the density difference between the produced intermetallic compounds. A Ce-Bi intermetallic compound was observed in the upper part, Hf at a concentration smaller than the error range was detected, and a Hf-Bi intermetallic compound which containing high concentration of Ce was observed in the lower part. Separation of high-purity Ce seems to be possible in the upper part, and it seems difficult to separate high-purity Hf in the lower part. Therefore, to separate highpurity Hf, an additional process suitable for it seems to be necessary.

We are crystallized to the linear low density polyethylene(LLDPE) particles by a thermally induced phase separation(TIPS). TIPS process based on the phase separation mechanism was performed for the LLDPE system which undergoes liquid-solid phase separation. The linear low density polyethylene particle formation occurred by the nucleation and growth mechanism in the metastable region. Although the growth rates depended on the experimental conditions such as the polymer concentration and temperature, the particles were larger when the polymer concentration was higher or temperature was higher. The particles were observed by SEM. The LLDPE particle size distribution became broader when the polymer concentration was higher.

당근종자의 발아율의 낮음과 발아지정의 문제점을 해결하기 위해서 Danver 126품종을 공시하여 여러가지 prime처리와 density separation 방법을 이용한 결과 다음과 같은 효과를 얻었다. 1. 여러가지 prime처리중 SMP처리(수분함량 90%, 6일간처리)에서 배의 생장이 아주 양호하였고 발아속도 및 발아율이 가장 좋았으며 종자에 피해도 없었다. 2. 무기염처리(0.2M KNO3 ＋0.1M K2 HPO4 )에 서는 배의 생장은 좋았으나 염에 의해 종자가 피해를 입었다. 3. SMP처리(수분함량 90%, 6일간)된 종자를 density separation한 결과 종자의 비중이 낮을수록 배의 생장이 컸으며 발아율 및 발아속도가 빨랐다.