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Discovery of C2 Swan Band and CN emission in Spark Discharge Experiment

  • Song, In-Ok;Mo, Younghoon;Ryu, Jein;Chang, Hoyon;Hwang, Ki-Wook;Chun, Man-Seog;Oh, Jinho;Hahn, Sangjoon
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.74.1-74.1
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    • 2021
  • 밀러-유리 실험으로 알려진 전기방전 실험은 지구초기대기를 모사하여 아미노산을 합성하여, 지구에서 생명의 기원을 연구하는 실험중의 하나이다. 메탄(CH4), 암모니아(NH3), 질소(N2) 가스를 주입하고 전기방전으로 에너지를 가했다. 그 결과 용액에서는 아미노산인 글라이신(C2H5NO2), 알라닌(C3H7NO2), 히스티딘(C6H9N3O2), 프롤린(C5H9NO2), 발린(C5H11NO2)이 검출되었고, 기존 Miller 1953과 Parker et al. 2014의 결과와 비교하였다. 전기방전에서는 C2 Swan Band 와 CN emission을 발견하였다. 이 두 방출선들은 혜성에서도 일반적으로 보여지는 방출선들이다.

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Experimental and simulation study on the backstreaming positive ions on the quarter-size negative ion source for CRAFT NNBI test facility

  • Yongjian Xu;Yuwen Yang;Jianglong Wei;Ling Yu;Wen Deng;Rixin Wang;Yuming Gu;Chundong Hu;Yahong Xie
    • Nuclear Engineering and Technology
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    • v.56 no.2
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    • pp.546-551
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    • 2024
  • As an effective methods of plasma heating, neutral beam injection (NBI) systems based on negative hydrogen ion sources will be utilized in future magnetic-confinement nuclear fusion experiments. Because of the collisions between the fast negative ions and the neutral background gas, the positive ions are inevitable created in the acceleration region in the negative NBI system. These positive ions are accelerated back into the ion source and become high energy backstreaming ions. In order to explore the characters of backstreaming ions, the track and power deposition of backstreaming H+ beam is estimated using the experimental and simulation methods at NNBI test facility. Results show that the flux of backstreaming positive ions is 1.93 % of that of negative ion extraction from ion source, and the magnet filed in the beam source has an effect on the backstreaming positive ions propagation.

North Korean Research Institutes for Plant Resources and the Actual Conditions of Their Agricultural Usage

  • Lim, Sang-Cheol;Kim, Wan-Seok
    • Korean Journal of Plant Resources
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    • v.23 no.6
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    • pp.550-553
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    • 2010
  • The representative research institutes in North Korea are the Academy of Science and the laboratories of major universities. The National Academy of Science consists of headquarters, Academy of Medicinal Science, Academy of Forestry Science, and Academy of Agricultural Science. Under the authority of the National Academy of Science, Central Information Agency for Science and Technology (CIAST) has built up a database system integrating all the science technology data to provide scientific and technological information. The major universities of North Korea include Kim Il-sung University, Kim Chaek University of Technology, Pyongyang Agricultural College, and Wonsan Agricultural College, and an agricultural college is situated in each province. Out of 3,860 plant species in North Korea, 158 species which amounts to approximately 4% of the total are rare and endangered, and deforestation is under a critical situation. The Oriental Medicine (Koryo Medicine) has been well developed using medicinal plants, and practical researches on biotic pesticide are largely conducted as an alternative to tackle the shortage of farming materials. Hereafter, a South-North joint research on the amount of plant resources and the methods of its conservation is needed and the North Korean research areas of biotic pesticide are worth adopting to the South Korean eco-friendly organic agriculture.

Analysis of Nutritional Components of Euonymus sieboldiana Leaves (참빗살나무 어린 순의 영양 성분 분석)

  • Kang, Min-Seung;Kim, So-Young;Lee, Yeon-Hee;Choi, Je-Wol;Baek, O-Hyun;Han, Hye-Kyung;Kim, Se-Na;Kim, Jung-Bong;Park, Hong-Ju;Cho, Young-Suk
    • Journal of the East Asian Society of Dietary Life
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    • v.21 no.6
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    • pp.918-923
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    • 2011
  • This study was aimed to investigate the nutritional components such as proximate content, minerals, vitamins, and dietary fiber of Euonymus sieboldiana leaves. The leaf sample used was fresh material produced in April in the Republic of Korea. As a result, the fresh leaf sample contained 10.30% crude carbohydrates, 7.42% crude proteins, 0.69% crude fat, and 1.46% crude ash, including a high amount of potassium (0.73%). The total dietary fiber, insoluble dietary fiber, and soluble dietary fiber content was 8.77%, 7.60%, and 1.17%, respectively. Vitamin C was found to be 44.53 mg% using colorimetric analysis. We regarded E. sieboldiana as a potential health food material because of its abundant nutritional components like potassium, dietary fiber, and vitamin C.

Overproduction of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) confers resistance to the herbicide glyphosate in transgenic rice

  • Lee, Soo-In;Kim, Hyun-Uk;Shin, Dong-Jin;Kim, Jin-A;Hong, Joon-Ki;Kim, Young-Mi;Lee, Yeon-Hee;Koo, Bon-Sung;Kwon, Sun-Jong;Suh, Seok-Chul
    • Journal of Plant Biotechnology
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    • v.38 no.4
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    • pp.272-277
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    • 2011
  • Plants expressing Agrobacterium sp. strain CP4 5-enolpyruvylshikimate-3-phosphate synthase (CP4 EPSPS) are known to be resistant to glyphosate, a potent herbicide that inhibits the activity of the endogenous plant EPSPS. In order to develop herbicide-resistant rice, we prepared transgenic rice plants with CP4 EPSPS gene under the control of CaMV 35S promoter for over-expression. A recombinant plasmid was transformed into rice via Agrobacterium-mediated transformation. A large number of transgenic rice plants were obtained with glyphosate and most of the transformants showed fertile. The integration and expression of CP4 EPSPS gene from regenerated plants was analyzed by Southern and northern blot analysis. The transgenic rice plants had CP4 EPSPS enzyme activity levels more than 15-fold higher than the wild-type plants. EPSPS enzyme activity of transgenic rice plants was also identified by strip-test method. Field trial of transgenic rice plants further confirmed that they can be selectively survived at 100% by spay of glyphosate (Roundup$^{(R)}$) at a regular dose used for conventional rice weed control.