• Journal of Soil and Groundwater Environment
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• v.12 no.5
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• pp.73-85
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• 2007

In this study, the experiment of solid-phase microextraction (SPME) technique using GC/FID was conducted as a possible alternative to liquid-liquid extraction for the analysis of EGBE, DGBE, DBM and TGME in water, and also, an optimization condition of trace analysis for disel oxygenates including EGBE by the design of experiment (DOE) was described. Experiments used a fractional factorial design method followed by central composite design allowing optimization of a number of factors as well as statistical analysis of the results. The response surface analysis showed that the extraction efficiency could be represented by a second-order polynomial equation in which the salts concentration, extraction temperature, extraction time and sonication time are the major influences. Using DOE method, a new datadependent method was developed to improve the quantity of confidently analyzed disel oxygenates in water samples.

• Proceedings of the KSCN Conference
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• 2004.05a
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• pp.439.3-440
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• 2004

미량 무기질은 인체의 대사와 생리기능 조절에 중요한 역할을 수행하는 것으로 보이나 체내에 미량 존재하므로 연구수행에 어려움이 많은 편이다. 한국인을 위한 영양 권장량(RDA)이 설정된 미량 무기질은 현재 철분과 아연뿐이며, 셀레늄, 구리, 망간, 크롬 및 몰리브덴에 대해서는 안전적정섭취범위(ESADDI)로 정해져 있다. 이는 이들 미량 원소의 섭취실태, 영양상태 또는 대사에 관한 연구결과가 거의 없기 때문이다. 이에 본 연구에서는 성인 여자 19명을 대상으로 위의 7가지 미량 금속무기질에 대해 일상 식사를 통한 섭취량, 혈중 농도 및 소변을 통한 배설량을 분석하였다.(중략)

• Proceedings of the Optical Society of Korea Conference
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• 2002.07a
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• pp.236-237
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• 2002

원자력 발전소에서 사용되는 연료의 효율을 증가시키기 위해서는 반응로에서 연소된 연료에 잔존하는 미량의 란탄족 (lanthanide)과 악티늄족 (actinide) 원소를 측정하고, 동위원소 성분비를 분석하는 작업이 필요하다. 이러한 미량원소 측정에는 흡수분광학 (absorption spectroscopy) 방법이 주로 사용되고 있다. 최근 들어 단일 종 모드 (single-longitudinal mode) 반도체 레이저가 개발되면서 미량원소 분석을 위한 분광 기술이 급속히 발전하고 있다. 반도체 레이저는 동작시킬 때 전력소모가 적고, 설치 공간이 작다는 점 때문에 현장 적용이 용이하므로 미량원소 측정 연구의 광원으로 많이 활용되고 있다. (중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.527-531
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• 2003

석탄가스화 생성물에서 발생하는 미량의 유황가스를 정제하기 위해서는 먼저 석탄가스화에서 발생하는 미량의 유황가스의 분석이 필요하다. 이러한 초미량 분석을 위한 기기들은 현재 시중에서 너무나 고가로 판매되고 있기에 본 연구에서는 비교적 저렴하고 절차가 간단한 분석방법을 개발키로 한 동기가 부여되었다.(중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.15 no.2
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• pp.157-164
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• 2009

The metals such as Al, Ag, Au, Cu, Cd, Co, Fe, Ni, Pb, Zn, etc are present at very low concentration in seawater and are classified as so-called trace metals. Whiles some of them are used in metabolism of living organism as a micronutrient, they may show toxic effects on organisms in case of a limited threshold concentration of them Plenty of studies on trace metals have been performed bemuse trace metals have a persistent influence and an adverse effect on marine environment and ecosystem. For long years, when the concentration of trace metals in natural waters such as seawater and fresh water are measured with high precision and accuracy, some systematic errors have been recognized to be present in measurements. Since 1975 in US and European countries, the measured concentration of trace metals in seawater have been found to be lower by factors of 10-1,000 than the previous data of trace metals measurements and the vertical profiles of the measurements have been shown to reflect well-known biological, physical and geochemical processes. These results are attributed to great advances in analytical instrumentation and methodology for trace metals measurements. Precautions against the contamination of samples are required to be taken in the process of sampling, storage, and analysis of samples. However, in Korea, erroneous data of trace metals with regard to ocean and marine environment related survey and investigations are reported The lock of exact understanding and information regarding precautions in sampling, storage and analysis of samples lead to the deterioration of data quality, especially in the analysis of trace metals. The major procedures to obtain the accurate data of trace metals in natural waters are introduced for applying to the study and assessment of marine environments.

• Analytical Science and Technology
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• v.20 no.5
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• pp.370-382
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• 2007

In this study, solid-phase microextraction (SPME) technique using GC/FID was studied as a possible alternative to liquid-liquid extraction for the analysis of EGBE, DGBE, DBM and TGME in water, and an optimization condition of trace analysis of EGBE, DGBE, DBM and TGME using the factorial design was described. Experiments used a fractional factorial design method followed by central composite design allowing optimization of a number of factors as well as statical analysis of results. The response surface analysis showed that the extraction efficiency can be described by a second-order polynomial equation in which the salts concentration, extraction temperature, extraction time and sonication time are the major influences. Using DOE, a new data-dependent method was developed that improved the quantity of confidently analyzed EGBE, DGBE, DBM and TGME in water samples.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.266-267
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• 2003

최근, 기계의 분석 정밀도가 높아짐에 따라 어류 이석 내 미량원소를 이용한 연구가 활발히 진행되고 있다. 이석은 균형감각기관으로서 칼슘과 단백질의 복합구조로 이루어져 있으며, 어류의 전 생활사에 걸쳐서 성장한다. 이렇게 형성된 어류의 이석내 화학조성은 형성 후엔 변화하지 않는다는 특징을 가지고 있다(Campana,1999). 위와 같은 특징을 바탕으로 이석 내 미량원소 또는 동위원소의 함량비율을 분석하여 어류에 대한 계군분리, 어류의 서식환경 추적, 오염 정도, 그리고 어류의 회유 유무와 경로, 연령사정 등의 연구를 하고 있다(Campana, 1999). (중략)

• Analytical Science and Technology
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• v.21 no.5
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• pp.397-402
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• 2008

Uranium dioxide was dissolved with nitric acid and a trace amount of HF. The analytical conditions of a spectrophotometer were investigated to determine a trace amount of silicon in the uranium matrices without a separation process. The effects of a trace amount of HF on the determination of silicon were examined. Boric acid was used to eliminate HF the interference in the colorimetric process. The recovery of silicon in the presence of a trace amount of HF in uranium solutions with or without saturated boric acid was $103.3{\pm}0.8$ and $76.6{\pm}6.8%$, respectively. The amount of saturated boric acid did not affect the recovery of the silicon. Therefore it was possible for this procedure to measure a trace amount of silicon in a uranium matrix without a separation by a UV-VIS spectrophotometry.

• Nuclear Engineering and Technology
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• v.13 no.4
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• pp.237-244
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• 1981

The preliminary concentration of trace elements in uranium dioxide using an anion exchange resin is presented for neutron activation analysis. The uranyl solution in sulfuric acid is adjusted to the acidity of about pH 2.7 and loaded on a column of the anion exchange resin. An appropriate volume of eluates obtained from the column shows good recoveries of trace elements. By combining this preconcentration with a radiochemical separation scheme, which was developed for the determinations of impurities in aluminum, it is possible to determine 21 trace elements in reactor grade uranium dioxide.

• Journal of the Korean Chemical Society
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• v.52 no.6
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• pp.637-648
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• 2008