Molten salt reactor (MSR) uses fluoride or chloride based molten salt as a coolant of the system, and fuel materials are dissolved in the molten salt, therefore it can be act as both coolant and nuclear fuel. A few issues have arisen from early-stage research and development program of MSR from Oak Ridge National Laboratory, including corrosion of structural materials and fission product management. For investigating the effect of additives on corrosion of structural materials, Mg(OH)2 and MgCl2*6H2O are added into the NaCl-MgCl2 eutectic salt. Prepared chloride salt is injected into the autoclave in the glove box, as well as corrosion coupons for candidate structural materials for molten chloride salt reactor, SS316, Alloy 600, and C-276 are also prepared. The temperature is set as 700°C. After 500 h corrosion experiment, the samples are taken out from the autoclave, and they are analyzed with scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). SS316 samples show weight loss with all salt conditions, while Alloy 600 and C-276 show weight gain after the corrosion experiment.

The effect of Li2O addition on precipitation behavior of uranium in LiCl-KCl-UCl3 has been investigated in this study. 99.99% LiCl-KCl eutectic salt is mixed with 10wt% UCl3 chips at 550°C in the Pyrex tube in argon atmosphere glove box, with 10 ppm O2 and 1 ppm H2O. Then, Li2O chunks are added in mixed LiCl-KCl-UCl3 and the system has been cooled down to room temperature for 10 hours to form enough UO2 particles in the salt. The solid salt has been taken out from the glove box, and cut into three sections (top, middle and bottom) by low-speed saw for further microscopic analysis. Three pieces of solid salt are dissolved in deionized water at room temperature and the solution is filtered by a filter paper to collect non-dissolved particles. The filter paper with particles is baked in vacuum oven at 120°C for 6 hours to evaporate remaining moisture from the filter paper. Further analysis was performed for the powder remaining on the filter paper, and periphery of the powder (cake) on the filter paper. Scanning electron microscopy (SEM), electron diffraction spectroscopy (EDS), and X-ray powder diffraction (XRD) are adopted to analysis the characteristic of the particles. From SEM analysis, the powders are consisted of small particles which have 5 to 10 m diameter, and EDS analysis shows they are likely UO2 with 23 at. % of uranium and 77 at. % oxygen. Cake is also analyzed by SEM and EDS, and needle like structures are widely observed on the particle. The length of needle is distributed from 5 to 20 m, and it has 6 to 10 at. % of chlorine, which are not fully dissolved into deionized water at room temperature. From XRD analysis, the particles show the peak position of UO2, and the result is well matched with the SEM-EDS results. We are planning to add more Li2O in the system for fully reacting uranium in UCl3, and compare the results to find the effect of Li2O concentration on UO2 precipitation.

The effect of oxidation time on the characteristics and mechanical properties of spent nuclear fuel cladding was investigated using Raman spectroscopy, tube rupture test, and tensile test. As oxidation time increased, the Raman peak associated with the tetragonal zirconium oxide phase diminished and merged with the Raman peak associated with the monoclinic zirconium oxide phase near 333 cm−1. Additionally, the other tetragonal zirconium oxide phase peak at 380 cm−1 decreased after 100 d of oxidation, whereas the zirconium monoclinic oxide peak became the dominant peak. The oxidation time had no effect on the tube rupture pressure of the oxidized zirconium alloy tube. However, the yield and tensile stresses of the oxidized nuclear fuel cladding tube decreased after 100 d of oxidation. The results of the scanning electron microscopy and transmission electron microscopy were represented with the in-situ Raman analysis result for the oxide characteristics generated on the cladding of spent nuclear fuel.

본 논문은 시학, 즉 시쓰기에 대한 인지학적 가능성에 대한 초기단계의 명상적 글쓰기를 탐구한다. 구체적인 방법으로서, 본인은 전체론적 방법으로 예이츠의 시학과 그의 자동기술에 대한 명상적 글로 시작하는데, 그의 집단 시학에 대해 선적 명상기법을 적용해보려고 한다.

예이츠 시, 특히 “아마도 음악에 부치는 시”에 나타나는 시적 광기와 시 적 무기력증을 대비해본다. 생리적 죽음과 같은 휴지부와 자아발견의 희열감을 torpor 와 fornit 개념으로 정리한다

예이츠의 환상록 속의 신비적-환상적 작품은 두 가지 인식 흐름, 즉 하 향적이거나 상향적 움직임, 다시 말해서 신적 존재의 하향적 목소리와 인간의 상향적 목소리의 흐름을 보인다. 이원적 의식의 흐름은 곧 시인의 인식론적 마음을 표현하는 과정이며, 불교의 중도론적 인식 과정을 대변한다. 예이츠의 신비학도 이 불가지 세계 에 대한 인식론적 반응이며, 대체적으로그의 문학적 의도성은 시인의 원소론적 마음을 드러내는 고정, 심학(心學)이라고 할 수 있다. 다만 만성제야 시에 드러나듯이, 4 원소 인의 인식 형상이 인식론적 도식화 과정의 어려움을 대변해준다.

Acrolepiopsis nagaimo (Yasuda, 2000) belonging to the family Acrolepiidae (Lepidoptera) is newly discovered in Korea. The species was first collected wild at Wol-ak-san [Mt.] a few years ago and they were recently found to infest Chinese yam, Dioscoreabatatas at a Chinese yam experimental field of the Institute for Bioresources Research located at Andong. Diagnostic characteristics of the adult are described and photographs of adult and male and female genitalia are provided.