• 대한화학회지
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• 제38권9호
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• pp.667-675
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• 1994

$La(OH)_3$를 공침제로 사용하여 해수중 흔적량 세 가지 원소를 동시에 부선시켜 정량하는 방법에 관하여 연구하였다. 인공해수를 사용하여 효과적인 부선을 위한 용액의 pH, 공침제의 양, 계면활성제의 종류와 양 등의 실험조건을 최적화시켰다. 부선하기 전에 Cr(VI)를 $NaBH_4$에 의하여 Cr(III)으로 환원시켜 크롬이 공침되도록 하였다. 해수시료 1.0 l에 $La^{3+}$를 가하고 용액의 pH를 9.8로 조절하여 $La(OH)_3$로 침전시키면서 흔적량 Co(III), Cu(II) 및 Cr(Ⅲ)이 공침되게 하였다. 부피 1:8의 0.5% sodium oleate와 sodium dodecylsulfate 에탄올 용액을 가하고 질소기체로 bubbling하여 침전들을 띄웠다. 뜬 침전을 분리해 내어 걸르고 씻은 다음 7.0 M $HNO_3$ 용액으로 녹여서 탈염수로 묽혀 25.0 ml가 되게 하였다. 분석원소들을 흑연료 원자흡수 분광광도법으로 정량하는데 인공해수로 표준용액을 만들어 검정곡선을 작성하였다. 이 방법을 동해와 서해의 물시료중 이들 원소분석에 응용하여 좋은 결과를 얻었다. 그리고 해수시료에 이들 원소를 일정량 첨가하여 얻은 회수율은 90.0% 이상으로 본 방법이 정량적임을 확인하였다.

• Journal of Nutrition and Health
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• 제25권2호
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• pp.123-131
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• 1992

한국인 수유부 21명의 모유에 함유된 무기질(Na, K, Ca, P, Mg)과 일부 미량원소(Mn, Mo, Ni)의 함량을 경시적으로 초유부터 12주의 성숙유에 이르기 까지 일정한 간격으로 세분하여 비교 분석하였다. 모유에 함유된 5종의 무기질과 8종의 미량원소들의 함량은 수유기간에 따라 유의적으로 감소하였다. 모유의 평균 나트륨 함량은 초유에서 293.01$\mu\textrm{g}$/$m\ell$, 이행유에서는 $251.24$\mu\textrm{g}$/m\ell$ 그리고 성숙유에서 $199.17$\mu\textrm{g}$/m\ell이었으며$ 칼륨농도는 각각 $436.18$\mu\textrm{g}$/m\ell,458.90,$ $390.10$\mu\textrm{g}$/m\ell이었다.$ 초유, 이행유 및 성숙유의 평균 칼슘 농도는 각각 $378.88$\mu\textrm{g}$/m\ell,$ $379.41$\mu\textrm{g}$/m\ell$ 그리고 $338.58$\mu\textrm{g}$/m\ell로$ 측정되었고 모유의 Ca/P의 비는 각각 3.39, 2.81과 2.45이었다. 또한 마그네슘 함량은 초유와 이행유에서 각각 $37~38$\mu\textrm{g}$/m\ell이었고$ 성숙유에서 $33.37$\mu\textrm{g}$/m\ell로$ 분석되었다. 모유의 평균 망간 함량은 초유와 이행유에서 각각 $0.024$\mu\textrm{g}$/m\ell,$ 성숙유에서 $0.014$\mu\textrm{g}$/m\ell,$ 믈리브덴의 평균 농도는 각각 $0.035$\mu\textrm{g}$/m\ell,$ $0.044$\mu\textrm{g}$/m\ell$ 그리고 $0.044$\mu\textrm{g}$/m\ell이었고$ 니켈 함량은 초유에서 $0.062$\mu\textrm{g}$/m\ell이행유에서$ $0.022$\mu\textrm{g}$/m\ell,$ 성숙유에서 $0.017$\mu\textrm{g}$/m\ell이었다.$ 수유기간에 따른 모유내 무기질과 미량원소 함량의 감소가 영아의 성장발달과 어떻해 관련 되는가에 관한 연구와 함께 유선조직에서 유즙으로의 무기질과 미량원소의 분비기전에 관한 생리학적 연구가 병행되어야 하겠으며, 본 연구결과가 앞으로 우수한 조제분유나 기타 영아식 개발에 활용되고, preterm milk의 무기질 성분을 비교하는데 이용될 수 있기를 희망한다.

• 자원환경지질
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• 제55권5호
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• pp.531-540
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• 2022

산성광산배수 내에서 침전하는 다양한 철광물들은 침전 과정뿐만 아니라 침전 후 다른 광물로 상전이를 거치면서 배수의 미량 원소의 농도 변화 및 이동성에 큰 영향을 미친다. 본 연구는 슈베르트마나이트가 주로 침전되는 것으로 알려진 달성광산의 산성광산배수 침전조에서 채취한 고체 침전물에 대하여 pH 및 시간에 따른 광물 특성 변화와 이와 연관된 배수내의 원소 농도 변화를 알아보았다. 그러나 채취된 시료의 주 구성 광물은 침철석으로 구성되어 있었으며 이는 이미 슈베르트마나이트가 어느 정도 침철석으로 상전이가 되어 있는 상태임을 지시한다. 실험 결과 배수의 pH가 높을수록 피크의 반치폭이 좁아지는 것이 관찰되었다. 이는 비정질에 가까운 슈베르트마나이트의 침철석으로의 전환 또는 침철석의 결정도 증가로 해석할 수 있으며 pH가 높을수록 이러한 변화가 큼을 보여준다. Fe의 농도도 pH에 큰 영향을 받으며 pH가 증가할수록 배수 내의 Fe의 농도는 감소하였다. 시간이 증가할수록 Fe의 농도는 증가하다가 추후 감소하였는데 이는 일부 슈베르트마나이트가 용해된 후 다시 침철석으로 침전하여 생긴 결과로 해석된다. 이런 결과로 황(S)의 경우 초기에 빠르게 증가하다 시간이 지나면서 더 이상 증가하지 않는 양상을 보여준다. S의 농도는 또한 슈베르트마나이트의 안정성과 관련이 있기 때문에 슈베르트마나이트가 안정한 낮은 pH에서는 낮은 농도를 그리고 침철석이 안정한 높은 pH에서는 높은 농도를 보여준다. 배수 내의 미량 원소들도 pH와 밀접한 연관성을 보여주며 일반적으로 pH가 낮을수록 높은 농도를 보이는데 배수 내 양이온으로 존재하는 미량원소의 경우 낮은 pH에서의 높은 용해도와 높은 pH에서의 침전과 표면 전하의 변화 등에 의한 것으로 해석된다. 이와 달리 비소(As)의 경우 배수 내 음이온으로 존재함으로 낮은 pH에서 높은 농도를 보여주지만 모든 pH 범위에서 시간이 지나면서 농도가 증가함을 보이는데 이는 광물 표면의 전하보다 슈베르트마나이트 등으로 As와 공침할 수 있는 Fe의 배수 내 농도와 관련이 있어보이며 시간에 따른 As의 증가도 슈베르트마나이트의 감소와 연관성이 있을 것으로 판단된다.

• 한국대기환경학회지
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• 제8권3호
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• pp.155-161
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• 1992

A simple, fast yet sensitive method is described for the determination of fifty elements in coal by inductively coupled plasma mass spectrometry. The method involves complete dissolution of coal with mixed acid $(HNO_3, HF, HClO_4)$ in hish pressure Teflon bomb and subsequent inductively coupled plasma mass spectrometric(ICP-MS) measurement. The accuracy of the method, being evaluated by the analysis of NIST SRMs (1632a, 1632b) is better than 20% RSD for most elements. The limits of detection defined by two times $\sigma$ (standard deviation of operational blank) are in order of sub-ppm to ppm, which are low enough to quantitate most elements. However, the determiantions for few elements such as V, As, Se are severely interfered by molecular ions such that their accurate determiantions are not possible. Analytical results for twentyon coals from eight countries including six ones world major coal producing, Korea, Japan, China, I.C.S., U.S.A., Canada, Australia, and South Africa are presented. While the results for major elements agree well with the existing ones, those for a few trace elements disagree considerably. The existing values are considerably higher. It is not possible to judge which are more accurate. However, the exisisting values are more likely to be errorous inasmuch as they are obtained without using high purity reagents and clean laboratory techniques.

• 자원환경지질
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• 제30권5호
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• pp.417-431
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• 1997

Characteristics of sedimentary rocks and enrichment of toxic elements in shale and coal from the Chungnam coal field were investigated based upon geochemistry of major, trace and rare earth elements. Shale and coal of the area are interbedded along the Traissic to the Jurassic Daedong Supergroup, which can be subdivided into grey shale, black shale and coal. The coal had been mined, however all the mines are abandonded due to the economic problems. The shale and coal are characterized by relatively low contents of $SiO_2$, and $Al_2O_3$ and high levels of loss-on-ignition (LOI), CaO and $Na_2O$ in comparison with the North American Shale Composite (NASC). Light rare earth elements (La, Ce, Yb and Lu) are highly enriched with the coal. Ratios of $Al_2O_3/Na_2O$ and $K_2O/Na_2O$ in shale and coal range from 30.0 to 351.8 and from 4.2 to 106.8, which have partly negative correlations against $SiO_2/Al_2O_3$ (1.24 to 6.06), respectively. Those are suggested that controls of mineral compositions in shale and coal can be due to substitution and migration of those elements by diagenesis and metamorphism. Shale and coal of the area may be deposited in terrestrial basin deduced from high C/S (39 to 895) and variable composition of organic carbon (0.39 to 18.40 wt.%) and low contents of reduced sulfur (0.01 to 0.05 wt.%). These shale and coal were originated from the high grade metamorphic and/or igneous rocks, and the rare earth elements of those rocks are slightly influenced with diagenesis and metamorphism on the basis of $Al_2O_3$ versus La, La against Ce, Zr versus Yb, the ratios of La/Ce (0.38 to 0.85) and Th/U (3.6 to 14.6). Characteristics of trace and rare earth elements as Co/Th (0.07 to 0.86), La/Sc (0.31 to 11.05), Se/Th (0.28 to 1.06), V/Ni (1.14 to 3.97), Cr/V (1.4 to 28.3), Ni/Co (2.12 to 8.00) and Zr/Hf (22.6~45.1) in the shale and coal argue for inefficient mixing of the simple source lithologies during sedimentation. These rocks also show much variation in $La_N/Yb_N$ (1.36 to 21.68), Th/Yb (3.5 to 20.0) and La/Th (0.31 to 7.89), and their origin is explained by derivation from a mixture of mainly acidic igneous and metamorphic rocks. Average concentrations in the shale and coal are As=7.2 and 7.5, Ba=913 and 974, Cr=500 and 145, Cu=20 and 26, Ni=38 and 35, Pb=30 and 36, and Zn=77 and 92 ppm, respectively, which are similar to those in the NASC. Average enrichment indices for major elements in the shale (0.79) and coal (0.77) are lower than those in the NASC. In addition, average enrichment index for rare earth elements in coal (2.39) is enriched rather than the shale (1.55). On the basis of the NASC, concentrations of minor and/or environmental toxic elements in the shale and coal were depleted of all the elements examined, excepting Cr, Pb, Rb and Th. Average enrichment indices of trace and/or potentially toxic elements (As, Cr, Cu, Ni, Pb, U and Zn) are 1.23 to 1.24 for shale and 1.06 to 1.22 for coal, respectively.

• 한국입자에어로졸학회지
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• 제8권2호
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• pp.47-54
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• 2012

Paved road dust emissions were investigated 14 times on 12 main roads in Seo-Cho Gu, Seoul, Korea by vehicle-based mobile sampling system(Road Dust Monitoring System) during September to December 2011. Also, fourteen heavy metals present in the dust samples were analyzed by ICP. ICP analysis showed that one of major source of the road dust would be urban construction. A large amount of silt was found, which might be originated mainly from building construction and open beds of trees. Trace element and pollution indices of heavy metals(Cd, Cu, Ni, Pb, Zn) on the roads adjacent to the commercial area had higher concentrations than those on the roads adjacent to the construction and residential areas because of traffic density and heavy traffic.

• 한국대기환경학회지
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• 제20권3호
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• pp.397-409
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• 2004

There has been few studies of either domestic or international to apply CCT-ICP-MS for the precise analysis of As and Cr components associated with airborne particulate matter. To date, the use of CCT-ICP-MS is strongly recommended for the accurate analysis of the toxic trace metals; this is because CCT-ICP-MS technique prevents polyatomic spectral interferences involved in the determination of As and/or Cr components. Taking advantage of CCT-ICP-MS technique, the measurements of about 20 metals were undertaken in this study. The standard reference material (NIST SRM 2783) was used for analytical quality control. To improve analytical accuracy and of acid efficiency, we selected nitric acid based on a test of three kinds of acid for microwave digestion method 1 ) nitric acid. 2) nitric acid and hydrogen peroxide. and 3) nitric acid and perchloric acid. When this method was employed, relative errors to SRM values of Al, As, Cr Fe, Mg, Mn, Pb, Sb, V, and Zn fell below 20%, while those or Ca, Si, and Ti were higher than 20%. The overall results of our study show that the concentrations of As and V determined by CCT-ICP-MS were satisfied with the certificated values within a relative error of 20e1c, whereas those determined by ICP-MS were 10 times higher than the certificated values.

• 환경위생공학
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• 제17권1호
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• pp.41-51
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• 2002

This research was carried out using Anderson air sampler which were set up on the roof of the Engineering College of Konkuk University at Hwayang-Dong, Kwangjin-Gu, Seoul from Aug. 1992 to foul. 1999. The results are as follows: The major component of yellow sand is soil particles based upon the observation that particles ranging from $3.3~7.0{\mu}m$ occupy 36~63%. It is certain that the increase of fine particles of respirable dust during yellow sand phenomenon in Seoul area affects the human body. The trace metals from natural sources like Al, Ca, Fe, K, Na, and Si show larger mass median diameter(MMD) values during yellow sand phenomenon than in normal situations while the values of MMD for Mn and Pb rarely changes. Noticeably, the changes in value of MMD of water soluble elements like ${NO_3}^{-}$ and ${SO_4}^{2}$ are 2.3 and 6.6 times higher during the yellow sand phenomenon compared to normal situations, respectively. This fact is regarded as decisive evidence showing that ${NO_3}^{-}$ and ${SO_4}^{2}$ in the air are attached to yellow sand and move together.

• 분석과학
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• 제8권4호
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• pp.435-442
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• 1995

A matrix modification was studied for the determination of trace bismuth in water samples by graphite furnace atomic absorption spectrophotometry. The type and quantity of modifiers as well as the use of auxiliary modifiers were investigated to realize the efficient modification. Palladium was chosen as a single modifier. By the addition of palladium($5{\mu}g/mL$) to 100 ng/mL bismuth solution, the temperatures could be raised from $500^{\circ}C$ to $1,300^{\circ}C$ for the charring and from $2,000^{\circ}C$ to $2,200^{\circ}C$ for the atomization as well as the sensitivity and reproducibility were improved. The absorbance of bismuth was maximum and not changed in the range of Pd $3-25{\mu}g/mL$. And several materials were examined as an auxiliary modifier. The mixed solution of $1{\mu}g/mL$ palladium and $200{\mu}g/mL$ nickel have raised the temperatures as with $5{\mu}g/mL$ palladium only. The maximum absorbance of bismuth was shown in the nickel concentration range of $100-300{\mu}g/mL$ in $1{\mu}g/mL$ palladium modified system. With such optimum conditions, the trace amount of bismuth in several water samples could be determined by a calibration curve method, and good recoveries were also obtained.

• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.393-397
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• 2008

Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used to determine the presence of germanium and phosphorus in a pure gold bonding wire. The samples were dissolved with hydrobromic acid and nitric acid at room temperature. The quantitation limits were 0.012 mg L-1 at 265.118 nm for Ge and 0.009 mg L-1 at 177.495 nm for P. Using the mixed acid digestion formula of DIW+HBr+HNO3, the recoveries were in the range of 98-100% and the relative standard deviation was within 1.1-2.3%. On the other hand, the amount of Ge decreased by about 16.2% using DIW+HCl+HNO3, due to the formation of a volatile compound. The Ge contents determined using the external method and the standard addition method were 9.45 mg kg-1 and 9.24 mg kg-1, respectively, and the P contents, using the same methods, were 22.49 mg kg-1 and 23.09 mg kg-1, respectively. Both methods were successfully used to determine the trace amounts of P and Ge in the pure gold bonding wire samples.