• 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

• 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.

• Agrochemical news magazine
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• v.20 no.3 s.150
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• pp.27-29
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• 1999

• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.113-128
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• 2012

The chemical composition of the continental crust play an important role in understanding of crustal formation and evolution and quantifying other processes taking place within continental crust. We summarized geochemical data reported in the previous literature for the crustal rocks in the Korean Peninsula and divided their chemical composition into geologic time scale. In the variation diagram normalized by average composition of the upper crustal rocks, the geochemical characteristics of the upper crust during Triassic period is different from those of the upper crustal rocks after Jurassic period or before Precambrian. However, the geochemical characteristics of the Jurassic and Precambrian period are similar each other. Our summarized data indicate that the source material of Triassic upper crust may be different from that of Jurassic or Precambrian upper crust.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.25 no.3
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• pp.67-80
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• 2020

Zinc (Zn) is known as an essential micronutrient for phytoplankton in the ocean. In surface waters, most of total dissolved Zn presents as organic complexes, and organic complexation dominates the speciation of Zn in seawater. Organic complexation reduces the bioavailable fraction of Zn, the free metal ion (Zn²⁺), which present less than 5% in surface waters. In this paper, a brief introduction on chemical speciation of dissolved Zn in seawater and analytical method for chemical speciation measurement is provided. Some representative studies were also introduced to describe the importance of chemical speciation of Zn (or other trace metals) on bioavailability and biogeochemistry in the ocean.

• Proceedings of the Mineralogical Society of Korea Conference
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• 2002.05a
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• pp.70-73
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• 2002

국내 대부분의 회처리장은 연안에 위치하고 또한 해수를 석탄회 이송수로 사용하고 있다. 따라서 석탄회-염수의 상호작용에 하여 석탄회가 풍화가 진행되고 석탄회내의 독성 미량원소 용출특성도 육상처리장과는 다르게 나타날 것으로 예상된다. 염수와 석탄회의 반응에 의한 독성미량원소의 용출 및 거동, 그리고 석탄회의 풍화 진행양상에 대한 연구는 국내·외적으로 전무한 실정이다. 따라서, 본 역 구에서는 연안 석탄회 매립장에서의 염수-석탄회 반응에 의한 독성미량원소의 검출 및 거동, 그리고 석탄회의 풍화 진행양상에 대한 연구를 수행하였다.

• 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)

• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.439-443
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• 1973

2-Mercaptothiazoline is very sensitive reagent for silver, which have been used for highly selective amperometric determination of silver. A method is described for the determination of micro-quantity of silver by amperometric titration with 2-mercaptothiazoline in ammonical solution. Direct titration of milligram amount of silver (0.05∼1.00mg) is possible in the presence of a number of foreign ions in ammonical solution containing ethylenediaminetetraacetic acid as masking agent under atmosphere. The interfering elements are gold and platinum. The milligram amounts of silver can be determined by the proposed method within an error ${\pm}$5%.

• Life and Agrochemicals
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• s.251
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• pp.12-15
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• 2009

우리나라는 병해충 발생이 많고 토양도 너무나 척박하다. 친환경농자재의 효과는 논란의 중심에 서 있다. 특히 화학제품을 이용한 미량원소가 함유될 수 없기 때문에 미량원소 결핍현상도 자주 나타난다. 효과가 중요하지만 친환경농자재에서 효과를 얘기하는 것도 어려움이 많다. 양자를 조화시킨 한국형 과학영농이 논의되어야 할 시점이다.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.351-357
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• 2006

Recently there is increasing the flow of hazardous chemical substances caused by industrial waste waters into a main river. It is needed to make the high treatment in drinking water treatment plants for reducing a health risk. Therefore, the monitoring of trace hazardous chemical substances by the industrial waste water inflow is available increasing economical efficiency of river management as well as reduction of risk. In this study, the most important substance among numerical and quantitative trace hazardous chemicals is Hexachlorobutadiene in an effluent of industrial wastes. However all items of GroupII which was included with semiconductor, electricity/electron and metal assemble was not detected. It means that we must consider the characteristics and behavior of load pollutants to water resources to select monitoring items. That was called 'preparatory monitoring'. We can reduce an economical consumption as well as risks from these pollutants using the preparatory monitoring.