• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.582-588
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• 1995

The preconcentration and determination of trace Cd(Ⅱ), Cu(Ⅱ), Pb(Ⅱ), Mn(Ⅱ) and Zn(Ⅱ) in water samples were studied by the precipitate flotation using La(OH)3 as a coprecipitant. The analytes were quantitatively coprecipitated by adding 3.0 mL of 0.1 M La(Ⅲ) solution in a 1,000 mL water sample and adjusting the pH to 9.5 with NaOH solution. After the addition of the 1:8 mixed surfactant solution of each 0.1% sodium oleate and sodium lauryl sulfate, the solution was stirred with a magnetic stirrer for 10 minutes. The precipitates were floated to the surface by bubbling with nitrogen gas and collected in a small sampling bottle. The precipitates were dissolved in nitric acid and then the solutions were diluted to 25.00 mL with a deionized water. The analytes were determined by flame atomic absorption spectrometry. This procedure was applied to the waste water analysis. This technique was simple, convenient and especially rapid for the analysis of a large volume of sample. And also, from the recoveries of better than 92% which were obtained from real samples, this method could be judged to be applicable to the preconcentration and quantitative determination of trace elements in water samples.

• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.562-568
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• 2017

Background: The chemical characterization of metallic alloys and oxides is conventionally carried out by wet chemical analytical methods and/or instrumental methods. Instrumental neutron activation analysis (INAA) is capable of analyzing samples nondestructively. As a part of a chemical quality control exercise, Zircaloys 2 and 4, nimonic alloy, and zirconium oxide samples were analyzed by two INAA methods. The samples of alloys and oxides were also analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES) and direct current Arc OES methods, respectively, for quality assurance purposes. The samples are important in various fields including nuclear technology. Methods: Samples were neutron irradiated using nuclear reactors, and the radioactive assay was carried out using high-resolution gamma-ray spectrometry. Major to trace mass fractions were determined using both relative and internal monostandard (IM) NAA methods as well as OES methods. Results: In the case of alloys, compositional analyses as well as concentrations of some trace elements were determined, whereas in the case of zirconium oxides, six trace elements were determined. For method validation, British Chemical Standard (BCS)-certified reference material 310/1 (a nimonic alloy) was analyzed using both relative INAA and IM-NAA methods. Conclusion: The results showed that IM-NAA and relative INAA methods can be used for nondestructive chemical quality control of alloys and oxide samples.

• Economic and Environmental Geology
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• v.29 no.2
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• pp.171-182
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• 1996

Quaternary Jungok basalts are distributed along the old Hantan river in Mid-Korean Peninsula. They were flowed out from Mt. Ori and Upland (680 m), and they formed narrow and long basalt plateau showing the layers of 10 to 20 meters in thickness and about 95 km in length. Fifty seven samples were collected from the study area, and sixteen rock samples were selected and analysed for major and trace elements. The analyzed samples have alkalic composition and show a relatively restricted variation in major element chemistry (except MgO), as comparing to the that of trace element. Based on major element chemistry, a quantitative modelling of fractional crystallization by multiple linear regression method suggests that the chemical evolution of the evolved rocks can be generated by fractionation of olivine, plagioc1ase, clinopyroxene, and magnetite in proportion of 56 : 25 : 17 : 2, respectively. The calculated trace element abundances by mineral proportions estimated from major element modelling, however, underestimate the incompatible element concentrations in the evolved rocks. According to the incompatible element abundances, simple fractional crystallization process has difficulty to explain the chemical variation of the evolved rocks. It seems that the other processes, which enrichment of incompatible elements can occure without concomitant changes in major element compositions, are needed in order to explain the chemical variation of the Jungok basalts. Thus, the major elements and compatible trace elements variations of the Jungok basalts are due to fractional crystallization, but the incompatible elements variation is due to fractional crystallization superimposed on already varying concentrations caused by slightly different degrees of melting of the same source, and/or due to periodic replenishment, tapping and fractionation(RTF) processes.

• Journal of Nutrition and Health
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• v.12 no.3
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• pp.25-32
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• 1979

In order to investigate harmful trace elements in ford additives used in food processing the contents of Copper, Lead, Cadmium, Chromium, Manganese, Nickel and Iron are determined by Atomic Absorption Spectrophotometer. These Elements are Extracted with APDC-MIBK extract method. Samples are collected from the food Industrial companies in Korea. Samples studied as shown in Table 1 are food colors(3-samples, Flavoring Agents(7-samples), Acidifiers(4-samples) Baking Powders(4-samples), Emulsifiers(2-samples), Thickeners(2-samples), Antioxidants(2-samples), Intensifiers(2-samples), Seasonings(3-samples), modifiers (10-samples) Most of the food additives contained comparatively a little small amount of harmful trace elements. However, the contents of harmful trace elements of Sodium Carbonate, Food Yellow No.5, Food Blue No.1, Food Red No.2 and Alkalies added in noodles are significantly higher than the other food additives. The obtained results are as follows ; 1) Sodium Carbonate contained Cadmium; 16.73 ug/g and Lead ; 61.55 ug/g. 2) Food Yellow No. 5 contained Cadmium: 1.67ug/g and Lead; 23.46 ug/g. 3) Food Blue No. 1 contained Cadmium; 1. 16 ug/g and Lead; 23.46 ug/g. 4) Food Red Ho. 1 contained Cadmium; 1.91 ug/g and Lead 23.08 ug./g. 5) Alkalies added in noodles contained Cadmium; 6. 11 ug/g and Lead; 53.85 ug/g.

• Economic and Environmental Geology
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• v.40 no.1 s.182
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• pp.15-28
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• 2007

The study is for contaminations of major, rare earth and trace elements of the farmland soils from the Boeunjeil mine area. The results are compared with the soils of Chungjoo, Deokpyeong, Boeun and Chubu areas. Fe and S contents of the contaminated area are high relative to those from the uncontaminated areas, Chungjoo and Boeun areas. Trace elements of the contaminated area are high relative to those from uncontaminated area, Chunajoo, Deokpyeong, Boeun and Chubu areas. The trace elements ares divided into Cd, Ni, Sr, U, V, Zn and As, Co, Cu, Mo, Pb, Sb, based on these dispersion and correlation. Two groups show the positive correlation. Enrichment factor of potentially toxic elements from contaminated area is >5 value, but <4 value in the uncontaminated area. In the geoaccumulation index of the minor elements, the contaminated area has >1 value and the uncontaminated area has <1 value except Mn. Enrichment index of potentially toxic elements(As, Cd, Co, Cu, Ni, U, Zn) ranges from 0.3 to 87.0 in the contaminated area and from 0.4 to 3.9 in the uncontaminated area. Overall results show that the high contents of farmland soils for the elements(Fe, S, As, Cd, Co, Cu, Ni, U, Zn) indicate the contamination by coal-related activities.

• Bulletin of the Korean Chemical Society
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• v.16 no.5
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• pp.422-427
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• 1995

In a stream of water sample, trace metal ions are quantitatively coprecipitated with Indium hydroxide and filtered. The filtered precipitate is continuously dissolved in 3 M nitric acid and introduced to ICP directly. The lead, cadmium, and copper are concentrated more than 10-fold and determined with ICP-AES at a sampling frequency of 10/hour. The detection limits are 2.89, 1.43,0.52 ppb for lead, cadmium, and copper respectively. Recoveries of lead, cadmium, and copper are 98.7, 94.3, and 104.5% respectively. The RSD values for three elements are about 3-5% currently.

• Analytical Science and Technology
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• v.11 no.4
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• pp.311-315
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• 1998

Ultra trace metal impurities of high-purity sulfuric acid for semiconductor process have been determined in the concentration of lower than ppb (ng/g) level using high resolution inductively coupled plasma mass spectrometer (HR-ICP-MS).The acid samples were evaporated and concentrated by the factor of 20. No clement in the acids exceeded 1ppb level and most of the clements were determined below 10ppt (pg/g). Elements without spectral interference in mass spectrum, such as In, V, Mn, etc, were determined in the concentration of below 1 ppt level The recoveries in the range of 72% to 127.2% for 0.5 ppb spiked sample were obtained.

• Journal of Environmental Science International
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• v.23 no.6
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• pp.995-1001
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• 2014

When relations improve between North and South Korea, there will be demand for North Korean edible plants because of the low labor cost and similar environmental conditions. However, there is no reliable information about trace elements, metals, and metalloids in edible plants from North Korea. Selenium (Se) and germanium (Ge) have positive effects on basic human health and are therapeutical in diverse illnesses. Metal and metalloid (Cd, Pb) poisoning, on the other hand, can cause many health problems. Plants collected from North Korea had higher selenium content than those from South Korea. Although none of the collected species exceeded the permissible levels of cadmium and lead, their content in plants was significantly higher in North Korea than in South Korea. The high metal contents in plants collected from North Korea may be associated with the soil physicochemical properties as well as the accumulated amounts of elements in the soil.

• CELLMED
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• v.7 no.1
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• pp.1.1-1.10
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• 2017

Minerals are individual of the components of foods and are not produced in the body but essential for best possible health. Several essential metals are vital for the appropriate performance of various enzymes, transcriptional factors and proteins that are essential in various biochemical paths. Metals like zinc (Zn), magnesium (Mg), and manganese (Mn) are cofactors of hundreds of enzymes. Zn is involved in the synthesis and secretion of insulin from the pancreatic ${\beta}-cells$. Chromium (Cr) increases the insulin receptors activity on target tissues, mainly in muscle cells. Insulin hormone is required to maintain the blood glucose amount in normal range. Continual increase of blood serum glucose level leads to marked chronic hyperglycemia or diabetes mellitus. Deficiency of insulin or its resistance, blood glucose level exceeds the upper limit of the common range of 126 mg/dl. Poor glucose control and diabetes changes the levels of essential trace elements such as Zn, Mg, Mn, Cr, iron etc. by rising urinary excretion and their related decrease in the blood. The aim of this article to discusses the important roles of essential trace elements in particular perspective of type 2 diabetes.

• Analytical Science and Technology
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• v.10 no.6
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• pp.459-467
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• 1997

Due to the growing demand for bottled mineral waters, a study was undertaken to determine the quality of the twenty six brands of domestic and imported drinking waters. The quality of water was evaluated by analyzing the twenty four elements including minerals, essential and/or toxic trace elements, and the analytical items to affect the taste of water. The contribution of drinking water to the mineral nutrition of human was calculated in order to investigate the health effect of drinking water. The taste of water was evaluated in terms of minerals, anions, TDS, alkalinity, hardness and pH.