• Journal of the Mineralogical Society of Korea
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• v.14 no.1
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• pp.31-38
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• 2001

방해석 결정 성장시 나타나는 미량금속 양이온의 분배현상을 표면침전 및 연속 결정 성장과정을 통하여 관찰하였다. A, B, C 유형의 순수한 방해석이 각각 3가지 다른 초기 농도 즉 0.02, 0.2, 0.4M의 $CaCl_2$.$2H_2$O로부터 형성되었으며 이들의 표면 형태는 합성용액의 조성과 성장 속도에 의해 조절됨을 알 수 있었다. B 유형이 표면형태가 좀더 복잡하지만 A, B 유형은 대체로 단순한{1014}면을 가진 방해석과 유사한 표면형태를 보여준다. 이에 반해 C 유형에서는 {0112}면이 주로관찰되었다. 순수한 방해석 위에 $(Ca, Me)CO_3$층의 대해 {1014}면 3 방향에 대한 전자현미분석 결과 금속이온의 특징적인 분배현상을 알수 있었다. $Mn^{2+}$ /과 $Co^{2+}$ 는 {0112} 에 수직으로 반면 $Sr^{2+ }$ /는 {1014}에 수직 또는 평행한 방향으로 선택적으로 분배되는 현상이 관찰되었다. 합성 방해석 표면 형태에 따른 금속 이온들의 분배 친화도를 Mn$^{2+}$ 이 C 유형>B 유형 >A 유형 그리고 $Co^{2+}$ 은 B 유형 >A 유형 >C 유형이다. 이들중 $Sr^{2+}$는 특히 {1014}면이 잘발달된 A유형에 더 많은 친화도를 갖는 것으로 나타났다.

• The Korean Journal of Quaternary Research
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• v.10 no.1
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• pp.27-52
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• 1996

금강 퇴적물의 지화학적 특성을 파악하기 위하여 상류에서 하류까지 21개의 표층 퇴적물을 채취하고 총금속(Al, Fe, Mn, Cr, Co, Ni, Cu, Zn, Pb) 입도별 금속 및 존재형태별 금속을 분석하였다. 또한 하천에서 연안역까지 미량금속의 공간적 변화를 보기 위해 부유물 을 일정 간격으로 채취하여 미량금속을 분석하였다. 퇴적물 중 미량 금속 함량을 평균 입도 와 밀접히 관계하여 변화하며 세립질실트 이하 부분에서 가장높은 함량을 보였고 이 높은 함량은 하천 부유물 중 금속 함량과 Mn을 제외하고 거의 유사한 수준이었다. Pb은 조립질 모래에서도 높은 함량을 보이는데 이는 조립질 모래에 많이 포함된 정장석에 의한 영향이 되고 세립질 실트에서의 높은 금속 함량은 세립한 중광물에 의한 영향이다. Mn과 Pb을 제 안한 금속들은 퇴적물 중 주로(70% 이상) 결정 격자와 관계하여 존재하는데 이는 퇴적물의 주구성 입도가 조립하여 금속이 풍부하고 세립한 중광 물에 의한 영향이 크기 때문이다. 하 천에서 염하구로 금속 함량이 급격히 감소하는데 이는 용존 $Mn^{+2}$이온이 $MnO_2$로 변화하는 산화반응과 하천구역에서의 퇴적 그리고 염하구에서 금속이 적어 진 입자(염하구 내에서 유기물 분해/용해로 만들어지거나 재부유 작요에 의한 조립질 물질) 와 하천 부유물과의 혼합작용에 의해 이루어진다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1996.10a
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• pp.50-50
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• 1996

• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.20-34
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• 2006

This study was undertaken to assess the anthropogenic impact on trace metal concentrations (Zn, Cu, Pb, Cr, Ni, and Cd) of roadside sediments (N = 70) from No.7 national road within the watershed of Hoidong Reservoir in Pusan City and to estimate the potential mobility of selected metals using sequential extraction. We generally found high concentrations of metals, especially Zn, Cu and Pb, affected by anthropogenic inputs. Compared to the trace metal concentrations of uncontaminated stream sediments, arithmetic mean concentrations of roadside sediments were about 7 times higher for Cu, 4 times higher for Zn, 3 times higher for Pb and Cr and, 2 times higher for Ni and As. Speciation data on the basis of sequential extraction indicate that most of the trace metals considered do not occur in significant quantities in the exchangeable fraction, except for Cd and Ni whose exchangeable fractions are appreciable (average 29.3 and 25.8%, respectively). Other metals such as Zn (51.4%) and Pb (45.2%) are preferentially bound to the reducible fraction, and therefore they can be potentially released by a pH decrease and/or redox change. Copper is mainly found in the organic fraction, while Cd is highest in the exchangeable fraction, and Cr and Ni in the residual fraction. Considering the proportion of metals bound to the exchangeable and carbonate fractions, the comparative mobility of metals probably decreases in the order of Cd>Ni>Pb>Zn>Cr>Cu. Although the total concentration data showed that Zn was typically present in potentially harmful concentration levels, the data on metal partitioning indicated that Cd, Ni and Pb pose the highest potential hazard for runoff water. As potential changes of redox state and pH may remobilize the metals bound to carbonates, amorphous oxides, and/or organic matter, and may release and flush them through drain networks into the watershed of Hoidong Reservoir, careful monitoring of environmental conditions appears to be very important.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.712-720
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• 2008

Sediment and interstitial water samples from ten lagoons in the Northeastern coastal part of South Korea were analyzed to obtain the concentrations of metals and inorganic ligand. These data, coupled with pH and ionic strength, were used to compute the aqueous speciation of the metals in the interstitial water using the MINTEQA2 equilibrium program. The K and Na were almost entirely present as the free aqua ions, but Co, Cd, Ni, Pb and Zn were existed as various metal-ligand complexes. Metals such as Al, As, and Cr formed 3$\sim$4 metal-ligand complexes. In the interstitial water with high chloride concentrations, almost all of the metals were dominated by free aqua ions. Metals of Cd, Co, Ni, Pb and Zn were bound as chloride-metal complexes of the type M$^{x+}$ + xCl$^-$, and Fe, Mn and Mg were dominated by sulfate equilibria(M$^{2+}$ + SO$_4{^{2-}}$). Hg(II) was speciated as HgCl$_2$(aq), HgCl$_3{^-}$ and HgCl$_4{^-}$. However, in the interstitial water with low chloride concentrations, Hg(II) and Cd(II) were existed as chloride-metal complexes, metals of Cu, Mg, Mn, Ni, Pb and Zn were dominated by sulfate equilibria, and the speciation of Fe(II) was bound as Fe(OH)$_2{^+}$, Fe(OH)$_3$(aq). However, Al, As and Cr were dominated by hydroxy-metal and oxide-metal species in nearly all of the lagoons.

• Analytical Science and Technology
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• v.13 no.1
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• pp.27-33
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• 2000

Simultaneous separation and analysis of Ni(II), Pd(II), Co(II), Cu(II) and Hg(II) in peperidinedithiocarbamate (PDTC) chelates were investigated by reversed phase liquid chromatography. The optimum conditions for the separation of PDTC metal chelates were examined with respect to the pH, extraction solvent, and mobile phase strength on Novapak $C_{18}$ column using methanol/water mixture as mobile phase. All metal PDTC chelates were eluted in an acceptable range of capacity factor value ($0{\leq}log\;k^{\prime}{\leq}1$). The linear calibration curves were obtained in the concentration range of $0{\sim}1.2{\mu}g/mL$ for five metal ions, and also good precision in the range of 1.96~3.41% RSD was obseved. Under the optimum conditions, trace metat ions in the composite water sample were successfully separated and determined with relative error of ${\pm}2.0%$.

• The Korean Journal of Malacology
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• v.31 no.2
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• pp.137-142
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• 2015

This study investigated concentration of trace metals, intersexuality and histopathology of digestive gland in Ruditapes philippinarum. Samples were collected from three areas of Gamak Bay in May, 2010. The concentration of trace metals showed that Al was highest, Zn was second high concentration and the lowest concentration was Cd. The intersexuality was 18.5% and female was higher than the male. Intersex type was observed one type. Destruction of digestive tubule epithelium was highest among other biomarkers in digestive gland. Distribution of basophilic cell was 5.8% and lipofuscin was 1.8%.

• 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.

• Analytical Science and Technology
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• v.5 no.2
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• pp.169-176
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• 1992

Analytical detection limits and Relative Ion Yield (RIY) by a jet type ion source glow discharge mass spectrometer(GD/MS) have been measured. With a jet type ion source, the sample loss rate for a Cu sample is 0.23 mg/min with 0.1 L/min gas flow rate and 0.11 mg/min with no gas flow rate. However, the ion intensity of Cu does not change significantly with thee variation of the gas flow rate. The RIY values obtained from the calibration curves of the six copper based standards were between 0.57 of Fe and 3.5 of Cr. The detection limits of most elements were in the range of 0.9 and 2.0 ppm when the glow discharge was operated at 4 mA, 1000V.

• Journal of the Korean Chemical Society
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• v.39 no.1
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• pp.40-46
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• 1995

A new analytical luminescence method for the Tb+3 and Eu+3 ions was studied using the fluorescence enhancement of the ions on the TLC plate. Compared to the specific emission intensities of the ions in aqueous or ethanol solution, if spotted on the TLC plate, the line intensities were extremely enhanced. There was additional enhancement effect of the lines from the ions on the TLC plate, if treated with ο-phenanthroline. Based on the luminescence enhancement, the detection limit of the ions was lowered more than 6 order of magnitude compared to the luminescence method using solution samples. The energy-transfer mechanism was also explained for the theoretical back ground of the luminescence enhancement.