The radiological characterization of SSCs (Structure, Systems and Components) plays one of the most important role for the decommissioning of KORI Unit-1 during the preparation periods. Generally, a regulatory body and laws relating to the decommissioning focus on the separation and appropriate disposal or storage of radiological waste including ILW (intermediate level waste), LLW (low level waste), VLLW (very low level waste) and CW (clearance waste), aligned with their contamination characteristics. The result of the preliminary radiological characterization of KORI Unit-1 indicated that, apart from neutron activated the RV (reactor vessel), RVI (reactor vessel internals), and BS (biological shielding concrete), the majorities of contamination were sorted to be less than LLW. Radiological contamination can be evaluated into two methods. Due to the difficulties of directly measuring contamination on the interior surfaces of the pipe, called CRUD, the assessment was implemented by modeling method, that is measuring contamination on the exterior surfaces of the pipes and calculating relative factors such as thickness and size. This indirect method may be affected by the surrounding radiation distribution, and only a few gamma nuclides can be measured. Therefore, it has limitation in terms of providing detailed nuclide information. Especially, α and β nuclides can only be estimated roughly by scaling factors, comparing their relative ratios with the existing gamma results. To overcome the limitation of indirect measurement, a destructive sampling method has been employed to assess the contamination of the systems and component. Samples are physically taken some parts of the systems or components and subsequently analyzed in the laboratory to evaluate detailed nuclides and total contamination. For the characterization of KORI Unit-1, we conducted the radiation measurement on the exterior surfaces of components using portable instruments (Eberline E-600 SPA3, Thermo G20-10, Thermo G10, Thermo FH40TG) at BR (boron recycle system) and SP (containment spray system) in primary system. Based on these results, the ProUCL program was employed to determine the destructive sample collection quantities based on statistical approach. The total of 5 and 8 destructive sample quantities were decided by program and successfully collected from the BR and SP systems, respectively. Samples were moved to laboratory and analyzed for the detail nuclide characteristics. The outcomes of this study are expected to serve as valuable information for estimating the types and quantities of radiological waste generated by decommissioning of KORI Unit-1.

The electrochemical reduction of carbon dioxide (CO2) to value-added products is a remarkable approach for mitigating CO2 emissions caused by the excessive consumption of fossil fuels. However, achieving the electrocatalytic reduction of CO2 still faces some bottlenecks, including the large overpotential, undesirable selectivity, and slow electron transfer kinetics. Various electrocatalysts including metals, metals oxides, alloys, and single-atom catalysts have been widely researched to suppress HER performance, reduce overpotential and enhance the selectivity of CO2RR over the last few decades. Among them, single-atom catalysts (SACs) have attracted a great deal of interest because of their advantages over traditional electrocatalysts such as maximized atomic utilization, tunable coordination environments and unique electronic structures. Herein, we discuss the mechanisms involved in the electroreduction of CO2 to carbon monoxide (CO) and the fundamental concepts related to electrocatalysis. Then, we present an overview of recent advances in the design of high-performance noble and non-noble singleatom catalysts for the CO2 reduction reaction.

Plasma Arc Melter (MSO) system has been developed for the treatment and the stabilization of various kinds of hazardous and radioactive waste into the readily disposable solidification products. Molten salt oxidation system has been developed for the for the treatment of halogen- and sulfurbearing hazardous and radioactive waste without emissions of PCDD/Fs and acid gases. However, PAM system has showed some difficulty in the off-gas treatment system due to the volatilization of radionuclides and toxic metals at extremely high-temperature plasma arc melter and the emissions of acid gases. MSO system has also showed the difficulty in the treatment of spent molten salt into the disposable waste form. Present study discussed the results of organics destruction performance tests for the PAM-MSO combination system, which is proposed and developed to compensate the drawbacks of each system. The worst-case condition tests for the organics destruction were conducted at lowest temperatures and the worst-case condition tests for the retention of metals and radionuclides were conducted at highested temperatures under the range of normal operating condition. For the worst-case organic destruction test, C6H5Cl was selected as a POHCs (Principal Organic Hazardous Constituents) because of its high incinerability ranking and the property of generation of chlorine gases and PCDD/Fs when incompletely destroyed. Simulated concrete waste spiked with 1 L of C6H5Cl was treated and the emissions of 17 kinds of PCDD/Fs and other hazardous gases such as CO, THCs, NOx, SO2 and HCl/Cl2 were measured. For the worst-case condition tests for the retention of metals and radionuclides, Pb and Cs were selected because of its high volatility characteristics. The emissions of PCDD/Fs was extremely lowered than the emission limit and those of other hazardous constituents were below their emission limit. The results of performance tests on the organics destruction suggested that tested PAM-MSO combination system could readily treat PCBs-bearing spent insulation liquid, spent ion-exchange resins used for the treatment of spent decontamination liquid in the decommission process and the concreted debris bearing hazardous organic coating materials. The decontamination factor of Cs and Co were 1.4×105, 1.4×105, respectively. The emisison of Pb was 0.562 ppm. These results suggested that tested PAM-MSO system treated low-level radioactive and pb-bearing mixed waste.

목적: 본 연구의 목적은 여러 산업의 선행연구들을 통하여 고객에게 제공되는 관계효익의 개념을 경제적 효익, 고객화효익, 사회적효익, 심리적효익으로 구분하여 전환장벽과 재구매의도에 미치는 영향에 대하여 확인하고자 하였다. 방법: 본 연구는 안경원에서 안경테, 안경렌즈, 콘택트렌즈를 구입하였던 347명의 고객을 대상으로 설문 조사하고 그 데이터를 분석하였다. 데이터 분석은 SPSS 18.0 통계프로그램을 이용하여 빈도분석, 요인분석, 회귀분석을 실시하여 안경원의 관계효익과 전환장벽, 재구매의도에 관한 연구 가설을 검증하였다. 결과: 첫째, 관계효익 중 심리적효익과 고객화효익이 전환장벽 형성에 긍정적인 영향을 미쳤다. 둘째, 관 계효익 중 세 요인, 즉 심리적효익, 경제적효익, 고객화효익이 재구매의도에 긍정적인 영향을 미치는 것으로 나타났다. 셋째, 전환장벽이 재구매의도에 긍정적인 영향을 미치는 것으로 나타났다. 결론: 본 연구에서는 안경원의 관계효익 중에서 심리적효익이 전환장벽과 재구매의도에 중요한 역할을 하 는 것과 관계효익의 네 요인 중 고객화효익이 전환장벽 형성과 재구매의도에 영향을 주는 것을 발견하였다. 경제적효익은 재구매의도 형성에만 영향을 미치므로 안경원 경영자는 안경사의 장기 근무를 위한 노력과 재 교육을 제공하여 고객관계관리를 통한 전환장벽 형성과 재구매의도를 높이려는 노력을 기울여야 할 것이다.

Beauveria bassiana is one of universal insect pathogenic fungi that have been used for biocontrol agent against insect pests. This fungus has also been studied for medicinal use. To meet for commercial use, the artificial production of the fruit body of this fungus has been established by the Mushtech Co in Korea. This study was carried out to define the morphological features of the fruit body of B. bassiana developed through artificial cultivation. For the observation of mycelia growth, B. bassiana was cultured on the Sabouraud Dextrose agar plus Yeast Extract(SDAY), nut-supplemented medium, and Fe ion-supplemented SDAY at 25℃ for 15 days. The variation of colony color was observed between the different media. Strong pigmentation was observed on Fe ion-supplemented SDAY. To investigate morphological characteristics of fruit body, geminating ascospores and vegetative hyphae were observed though light microscopy and scanning microscope. During seven weeks of cultivation period, the development process of apical fertile part of stromata can be separated by the development stage of perithecia. To understand the developing process of fruit body at the transcript level, investigating process of distinct gene expression according to cultural condition and developmental stage was discussed.

To understand the oviposition biology of arrowhead scale, Unaspis yanonensis (Kuwana) (Homoptera: Diaspididae), the longevity and fecundity of the overwintered females were examined at various temperatures (16, 20, 24, 28, and 32℃). The total fecundity increased with rising temperature, showed a maximum of 260.9 crawlers per female at 24℃, and then declined thereafter. Females showed a periodical oviposition activity. The 1st cycle fecundity was identified at all temperatures examined, and was not significantly different between 16 and 28℃. However, the 2nd cycle fecundity and later cycle fecundity were much lower at 16, 20, and 32℃ than those at 24 and 28℃. The pre-oviposition period ranged from 49.0 d at 16℃ to 19.7 d at 32℃, and was the shortest 19.4d at 28℃. The linear lines of mean development rates (1/mean pre-oviposition period) against temperatures provided the estimate of low-threshold temperature 8.7℃ for pre-oviposition stage and the thermal constant of 358.1 DD. The lower threshold temperature and thermal constant for the completion of U. yanonensis pre-oviposition period well predicted the first crawler occurrences in the fields.

Background : This study was conducted to determine the optimal conditions of growth medium, temperature, and light quality for efficient propagation of Pyrrosia petiolosa spores. Methods and Results : P. petiolosa spores were collected from Andong-si area in February 2015, and the spores were subjected to a careful selection process. The selected spores were stored at the Korea National Wild Plant Seed Bank (4℃, RH 40%) and used as our experimental materials (GR0000182302). The spore germination rate and prothalium development were high in Knop media (24.5%), which had low mineral content. The germination rate increased with the increase in temperature and reached its maximum, 24.5%, at 25°C. The germination rate was also measured under different light conditions, and the highest rate of 28.7% was observed under LED blue light compared to fluorescent lights (24.5%). The germinated spores developed into heart-shaped prothallia under LED blue light; however, 3 weeks after sowing, prothallium development decreased compared to fluorescent lights. Conclusion : In conclusion, the optimal P. petiolosa In vitro propagation method include spore germination on Knop medium at 25°C under LED blue light, and the change in light source to fluorescent light 3 weeks after sowing for prothallium formation and proliferation.