This study aimed to identify and analyze the effects of both isothermal heat treatment temperature and residence time on the formation of mesophase in coal tar pitch, especially with respect to its microstructural and crystalline evolution. The formation and growth of mesophase resulted in a decrease in d002 and an increase in Lc, and the degree of such variation was larger when the isothermal heat treatment temperature was higher. In isothermally heat-treated pitch, two distinct domains were observed: less developed crystalline carbon (LDCC) and more developed crystalline carbon (MDCC). When pitch was isothermally heat-treated at 375 °C for 20 h, d002 was 4.015 Å in the LDCC and 3.515 Å in the MDCC. Higher isothermal heat-treatment temperatures accelerated the formation, growth, and coalescence of mesophase. Indeed, in the pitch specimen isothermally heat-treated at 425 °C for 20 h, d002 was 3.809 Å in the LDCC and 3.471 Å in the MDCC. The evolution of mesophase was characterized by pronounced inflection points in d002 curves. It was found that the emergence of these inflection points coincided with pronounced changes in the microstructure of mesophase. This finding confirmed the relationship between inflection points in d002 and the microstructure of mesophase.

The effects of different plasma agent species ( CF4, N2) over the conductivity of CFX cathode material were identified. Both plasma treatments have surface etching effect, while the CF4 plasma treatment has C–F bond modification effect and the N2 plasma treatment has defluorination effect. The changes of surface chemical species and porosity along the plasma agent were elucidated. Moreover, the electrochemical properties of plasma-treated CFX confirmed the effects of plasma treatments. The charge-transfer resistance of plasma-treated CFX was maximum 60.3% reduced than the pristine CFX. The effects of surface chemical modification coupled with etching along the plasma gas agents were compared and identified with their reaction mechanisms.

네오니코티노이드계 농약은 전세계적으로 사용되는 강력한 살충제이지만 환경, 생물에 잔류하 여 악영향을 미치고 있다. 이에 본 연구는 네오니코티노이드계 농약인 imidacloprid와 clothianidin이 공시 작물인 알팔파와 적용작물로 고추와 오이를 선정하여 토양처리 및 경엽처리에 따른 꿀벌 독성과 엽상 잔류 량을 비교하여 기존 엽상잔류독성시험법의 문제점을 확인하고자 하였다. Imidacloprid와 clothianidin을 작 물 또는 토양에 권장량 및 배수로 처리하고 시간에 따른 꿀벌의 치사율에 대한 RT25를 확인하고 잎의 잔류 농약을 HPLC로 측정하였다. 그 결과 경엽처리하였을 때 imidacloprid은 공시작물 RT25가 1일 이하, 잔류 량은 1.07 ~ 19.27 mg/kg이나 적용작물은 RT25가 9일 이하, 잔류량은 1.00 ~ 45.10 mg/kg 수준이었다. clothianidin은 공시작물 RT25가 10일 이하, 잔류량은 0.61 ~ 2.57 mg/kg이나 적용작물은 RT25가 28일 이 하, 잔류량은 0.13 ~ 2.85 mg/kg 수준이었다. 토양처리했을 때 imidacloprid와 clothianidin은 공시작물에 서는 꿀벌에 영향을 미치지 않았으며 잔류량은 0.05 ~ 0.37 mg/kg 수준이었으나, 적용작물에서는 imidacloprid은 RT25가 28일 이하였고 잔류량은 4.47 ~ 130.43 mg/kg 수준이었고, clothianidin은 RT25가 35일 이하였고, 잔류량은 5.96 ~ 42.32 mg/kg 수준이었다. 결론적으로 꿀벌 독성과 엽상 잔류량을 작물간 비교하였을 때 공시작물 보다 적용작물이 꿀벌의 치사율에 많은 영향을 미치고 잔류량도 높게 나타났고, 처리방법에 따라 비교하였을 때 적용작물에 대한 토양처리가 경엽처리에 비해 높은 RT25와 잔류량이 나타 났다. 따라서 농약안전성 확보를 위해 제시된 시험법이 실제 적용작물과 농약 처리방법에 따라 차이가 있 을 수 있어 imidacloprid와 clothianidin의 안전성 평가를 위하여 다양한 경로의 연구가 필요하다.

In the context of the Ministry of Environment’s 2022 Climate Change Adaptation Plan for Public Institutions, public sewage treatment plants are one of the important targets for climate change response aimed at sustainable water management. In this study, it is applied a modified methodology to four water regeneration centers (public sewage treatment facilities) in charge of sewage treatment in Seoul to analyze the impacts and risks of climate change and discuss priorities for adaptation measures. The results of the study showed that heavy rains, heat waves, and droughts will be the key impacts of climate change, and highlighted the need for measures to mitigate these risks, especially for facility managers.