• 제목/요약/키워드: RoZ

검색결과 93건 처리시간 0.028초

Characterization of Individual Atmospheric Aerosols Using Quantitative Energy Dispersive-Electron Probe X-ray Microanalysis: A Review

  • Kim, Hye-Kyeong;Ro, Chul-Un
    • Asian Journal of Atmospheric Environment
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    • 제4권3호
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    • pp.115-140
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    • 2010
  • Great concerns about atmospheric aerosols are attributed to their multiple roles to atmospheric processes. For example, atmospheric aerosols influence global climate, directly by scattering or absorbing solar radiations and indirectly by serving as cloud condensation nuclei. They also have a significant impact on human health and visibility. Many of these effects depend on the size and composition of atmospheric aerosols, and thus detailed information on the physicochemical properties and the distribution of airborne particles is critical to accurately predict their impact on the Earth's climate as well as human health. A single particle analysis technique, named low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA) that can determine the concentration of low-Z elements such as carbon, nitrogen and oxygen in a microscopic volume has been developed. The capability of quantitative analysis of low-Z elements in individual particle allows the characterization of especially important atmospheric particles such as sulfates, nitrates, ammonium, and carbonaceous particles. Furthermore, the diversity and the complicated heterogeneity of atmospheric particles in chemical compositions can be investigated in detail. In this review, the development and methodology of low-Z particle EPMA for the analysis of atmospheric aerosols are introduced. Also, its typical applications for the characterization of various atmospheric particles, i.e., on the chemical compositions, morphologies, the size segregated distributions, and the origins of Asian dust, urban aerosols, indoor aerosols in underground subway station, and Arctic aerosols, are illustrated.

단풍취의 식물화학적 성분 (Phytochemical Constituents of Ainsliaea acerifolia)

  • 정칠만;권학철;최상진;이재훈;이동진;류수노;이강노
    • 생약학회지
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    • 제31권2호
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    • pp.125-129
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    • 2000
  • Three sesquiterpene lactones (1, 2 and 5) and two lipid glycerols (3 and 4) were isolated from MeOH extract of Ainsliaea acerifolia (Compositae). Based on spectral data, their chemical structures were determined as estafiatone (1), zaluzanin C (2), 3-O-(9Z, 12Z, 15Z-octadecatrienoyl) glycerol (3), 3-O-(9Z, 12Z-octadecadienoyl) glycerol (4) and glucozaluzanin C (5). Compounds 1, 3 and 4 were previously not reported from Ainsliaea species.

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단일입자분석(Low-Z Particle Electron Probe X-ray Microanalysis)을 이용한 도시 소각재 입자의 특성분석 (Single-Particle Characterization of Municipal Solid Waste (MSW) Ash Particles Using Low- Z Particle Electron Probe X-ray Microanalysis)

  • 황희진;김혜경;노철언
    • 한국대기환경학회지
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    • 제21권3호
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    • pp.367-375
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    • 2005
  • Low-Z particle Electron Probe X-ray Microanalysis was applied to characterize MSW fly- and bottom -ash particle samples originated from two municipal incinerators (denoted as A and B) in Korea. According to their chemical composition, many distinctive particle types were identified. In A fly ash, the major chemical species are carbon-rich, aluminosilicates and many particles are composed of as a mixture of $ CaCO_3$ and other chemical species such as $CaSO_4$ or $CaCl_2$. For B fly ash, Fe, iron oxide, NaCl and NaCl-containing particles are the most abundant. In bottom ash, A and B were composed of similar chemical species such as carbon-rich, Fe, iron oxide, $CaCO_3$, and aluminosilicates. It was demonstrated that the single-particle characterization using this low-Z particle EPMA technique provided detailed information on various types of chemical species in the MSW ash samples. In addition, the technique has advantage over conventional analytical techniques in the point that both crystalline and glass-like ash particles can be analyzed at the same time.

보안 정형 검증 도구를 이용한 보안 S/W 검증 방안 (Verification Methodology of Security S/W using Security Formal Verification Tool)

  • 김기환;장승주;박일환
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2005년도 춘계학술발표대회
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    • pp.1091-1094
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    • 2005
  • 보안 소프트웨어 개발을 위한 정형 기법은 소프트웨어의 안정성과 신뢰성을 보장할 수 있는 기반을 마련해 준다. 정형화 기법에는 정형 명세와 정형 검증으로 분류할 수 있으며, 이를 위해 여러 도구가 제공되고 있다. 본 논문에서는 보안 소프트웨어 개발을 위한 RoZ 정형 명세 도구를 이용하여 ACS(Access Control System)의 UML 모델을 통한 Z 명세 자동 생성 과정을 살펴본다. 그리고, 정형 검증 도구인 Z/EVES를 이용하여 ACS 의 특정 기능의 명세에 대한 검증 과정을 수행함으로써, 소프트웨어 설계에 따른 보안 소프트웨어의 안정성을 보장할 수 있는 개발 방안을 제시하였다.

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종로 청진 12~16지구 출토 나막신의 수종분석 (Species Identification for Excavated Wooden Shoes in the 12~16 Chungjin District of Jongno)

  • 오정애;박정민;김병로
    • 한국가구학회지
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    • 제26권2호
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    • pp.163-170
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    • 2015
  • This study was conducted to identify wood species for 51 excavated wooden shoes in the 12~16 Chungjin district of Jongno. Wood species of 31 Pinus sp., 12 Torreya nucifera S. et Z., 4 Ginkgo biloba L., 2 Salix sp., 1 Kalopanax pictus (Thunb.) Nakai. and 1 Morus sp. were identified. Wood used for wooden shoes was a species that can be mainly obtained easily around. Among them, Torreya nucifera S. et Z. grows in warm temperate zone of Korea, which shows that interregional cooperation has occurred.