• Title/Summary/Keyword: Fe-Cr

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Mineral Contents of Hot Water Extracts and Shell of Shellfishes from Western Coast of Korea (서해안 조개류의 껍질과 열수 추출물의 무기질 함량)

  • 김미정;이예경;김순동
    • Journal of the East Asian Society of Dietary Life
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    • v.11 no.4
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    • pp.289-294
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    • 2001
  • Yields of shells, appearance of the shellfishes, mineral contents of the shells and their hot water extracts were determined in six shellfishes such as corb shell(CS). short neck clam(SNC). taste clam(TC), ark shell(AS). top shell(TS) and oyster(OY) from the western coast of Korea. Yields of shells in shellfishes were 70.I~80.5% but yields of TC was the lowest as 40.7%. The highest among weight of the shell the shellfishes was the TS(26.2g) and the lowest weight was TC(5.6g) Colors of CS, SNC, TC. AS. TS and OY were yellowish brown, brown, black. greenish brown and gray. respectively. Ca content of the shell of shellfishes was 36.23~38.78% and the content of K and Na were 0.23~4.54% and 1.48~l.59%, respectively. Contents of Na, Mg, Fe. Mn, Zn, Cu. P and S were in the range of 0.01~0.21%. It also contained heavy metals, such as Pb(1.90~7.75 ppm), Cd(0.5~4.50 ppm), As (1.40~4.30 ppm), Se (0.2~l.50 ppm). Cr(1.00~8.30 ppm) and Hg(0.002~8.2 ppm), Ca content in hot water extracts of shell of shellfish was the highest in TC(2,448 mg/100 g), and the lowest in SNC(115 mg/100 g). K content in TC extracts was the highest with the levels of 952 mg/100 g. P content of TC and SNC were 201 and 0.36 mg/100 g, respectively. The contents of Pb, As, Se and Cr were the highest in the extracts of TC and were 110. 40. 90, 20 $\mu$g/100 g, respectively. But Cd was not detected in the extracts of SNC.

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Comparison of flux and natural sapphire after heat-treatment (열처리 후 플럭스 사파이어와 천연 사파이어의 비교 분석)

  • Kim, Ki-In;Ahn, Yong-Kil;Seo, Jin-Gyo;Park, Jong-Wan
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.19 no.3
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    • pp.152-158
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    • 2009
  • Various fabrication methods have been used to synthesize sapphire which has qualities of jewelry well beyond the industrial class. Among them, the flux sapphire of Chatham Company which has as high value as jewelry was selected in order to compare natural and synthetic sapphire. First, the WD-XRF (Wavelength dispersive x-ray fluorescence spectrometer) was used to analyze the chemical composition of natural and synthetic sapphire. Although natural sapphire had very diverse chemical compositions, flux sapphire had small quantities of Mo, Pt and Pb elements in addition to the similar chemical ingredients to natural one. Pt is decisive proof of flux sapphire. Next, by investigating spectroscopic characteristics using UV-VIS Spectrophotometer after heat treatment at high temperatures of $1300^{\circ}C$ and $1500^{\circ}C$, the variation of 690 nm absorbance related to $Cr^{3+}$ was detected in the natural sapphire while those of the 690 nm absorbance (related to $Cr^{3+}$) as well as absorbance of 376 nm and 388 nm ($Fe^{3+}$) were seen in the flux sapphire. It was found that the difference in the absorbance variation of flux sapphire is greater than that of natural sapphire after heat treatment. The chemical composition and spectrum analysis were utilized to compare the natural sapphire and the flux synthetic sapphire.

Potential Element Retention by Weathered Pulverised Fuel Ash : I. Batch Leaching Experiments (풍화 석탄연소 고형폐기물(Pulverised Fuel Ash)의 중금속 제거가능성 : I. 뱃치 용출실험)

  • Lee, Sanghoon
    • Economic and Environmental Geology
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    • v.28 no.3
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    • pp.251-257
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    • 1995
  • Three PEA (Pulverised Fuel Ash) samples, which were fresh, 17 and some 40 years weathered, were collected from two major British power plants. Batch leaching tests with these samples using distilled water and simulated industrial leachate showed higher amounts of element liberation from fresh ash, including Ca, Na, K, S (as $SO^{2-}_4$, $Cr_{total}$, Cu, Li Ni, Mo and CI and this seems to indicate their surface association and easier dissolution when contact with water. On the contrary Mg, Al, Ba, Si, V, As and Se do not show such readily leachable concentrations and these elements might be more associated with glass fraction in PFA particle rather than surface. Although element concentrations in the weathered ash are much lower than those in the initial leachate from the fresh ash, elements are still detected as resonable concentrations, with rather constant levels and this seems to demonstrate the element release from unstable glass phase of PFA particle. Fe, Ca, $Cr_{total}$, Cu, Ni, Zn and Hg were removed from the synthetic leachate by PFA and this is also confirmed by gain in solid PFA. The order of element retention is Meaford weathered ash > Drax weathered ash > Drax fresh ash in decreasing order and this conforms with the degree of weathering. Namely, the more wethered, the more wethered, the more effective in metal retention from the synthetic leachate.

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A Study on the Concentration Distribution of Airborne Heavy Metals in Major Industrial Complexes in Korea (국내 주요 산업단지 대기 중 중금속농도 분포에 관한 연구)

  • Kang, Byung-Wook;Kim, Min-Ji;Baek, Kyung-Min;Seo, Young-Kyo;Lee, Hak Sung;Kim, Jong-Ho;Han, Jin-Seok;Baek, Sung-Ok
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.2
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    • pp.269-280
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    • 2018
  • This paper reports the results of field evaluation to determine the levels of heavy metals in major industrial complexes in Korea over a seven year period (2007~2013). The measurement of heavy metal was conducted using quartz fiber filter sampling and ICP-AES analysis. In order to validate the analytical performance of these methods, studies were also carried out to investigate data quality control(QC) parameters, such as the method detection limit (MDL), repeatability, and recovery efficiencies. The average concentrations of total suspended particulates (TSP) for the nine industrial complexes in Korea were $104{\sim}169{\mu}g/m^3$, which was higher than other industrial complexes and urban areas. The Sihwa and Banwol industrial complexes were shown to be the biggest contributing sources to high TSP emission ($159{\mu}g/m^3$ and $169{\mu}g/m^3$, respectively). The concentrations of heavy metals in TSP were higher in the order of Fe>Cu>Zn, Pb, Mn>Cr, Ni, As and Cd. It was observed that Fe was the highest in the Gwangyang and Pohang steel industrial complexes. The concentrations of Zn and Pb were high in Onsan, Sihwa and Banwol industrial complexes, and this was attributed to the emission from the nonferrous industry. Additionally, Cr and Ni concentrations were high in the Sihwa and Banwol industrial complexes due to plating industry. On the other hand, Ulsan and Onsan industrial complexes showed high Cr and Ni concentrations as a response to the emission of metal industry related to automobile. The correlation analysis revealed the high correlation between Cr and Ni in plating industry from Sihwa and Banwol industrial complexes. Adding to this, components related to coal combustion and road dust showed high correlation in Pohang and Gwangyang industrial complexes. Then Onsan and Ulsan industrial complexes showed high correlation among components related to the nonferrous metals.

Pollution Status of Surface Sediment in Jinju Bay, a Spraying Shellfish Farming Area, Korea (살포식 패류양식해역인 진주만 표층 퇴적물의 오염도)

  • Lee, Garam;Hwang, Hyunjin;Kim, Jeong Bae;Hwang, Dong-Woon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.4
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    • pp.392-402
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    • 2020
  • We investigated the concentrations of acid volatile sulfide (AVS), ignition loss (IL), total organic carbon (TOC), total nitrogen (TN), and metallic elements (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, and Zn), in August 2015, to determine the spatial distribution and pollution status of organic matter and metals in the surface sediment of Jinju Bay, a spraying shellfish farming area, Korea. The concentrations of organic matter and metallic elements were significantly higher in the southern part of the bay than in the mouth and center of the bay. The C/N ratio (5.7~8.0) in the sediment represents the dominance of organic matter of oceanic origin in the surface sediment of the study area. The concentrations of AVS, TOC, and metals (As, Cd, Cr, Cu, Hg, Pb, and Zn) were much lower than the values of the sediment quality guidelines applied in Korea. Based on the results of the pollution load index (PLI) and ecological risk index (ERI), the metal concentrations in the surface sediment of Jinju Bay have a weakly negative ecological effect on benthic organisms although the sediments with high metal pollution status are distributed in the southern parts of the bay, with high dense shellfish farming areas. Thus, the surface sediments in Jinju Bay are not polluted with organic matter and are slightly polluted with metallic elements.

Characteristics of Heavy Metal Pollution in Contaminated Roadside Sediments in Jeonju City, Korea (전주시 도로변 퇴적물의 중금속 오염 특성)

  • Cho, Ktu-Seong
    • Journal of the Korean earth science society
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    • v.24 no.8
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    • pp.711-720
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    • 2003
  • To study characteristics of the heavy metal pollution, sediment samples were collected at 67 sites on the roadside of Jeonju city during summer and winter, 2002. The total concentration of metals including Cd, Co, Cr, Cu, Ni, Pb, Zn, and Mn in the sediment samples were determined. The results indicate that the roadside sediments in Jeonju city have lower (1/2 to 1/7 times) concentrations of Zn, Cu, Pb and Cd than the metal concentrations previously reported for roadside soil, dust and sewage sludges in Seoul. However, the metal concentrations are higher than environmental quality criteria in soil suggested from several countries, and Zn, Cu, Pb and Cd contents are usually 2-7 times higher than the world average contents of the metals in natural soil. Although pollution index and concentrations of Cr, Ni, Pb and Zn in the roadside sediments at industrial area were usually higher than those of downtown and residential area, the metal having small vehicle- and steel-related industries had high concentrations of metals. The results of chemical partitioning analysis showed that Pb, Zn and Mn are mainly associated with carbonate/adsorbed and Fe-Mn oxide phases but that Cu is largely associated with the organic and sulfide fractions. It thus indicates that both large and small (vehicle- and steel-related) industries are main sources of heavy metal contamination. Due to high solubility of the carbonate phases by natural leaching episodes, the carbonate/adsorbed Cd, Co, Ni, Pb, Zn and Mn in the roadside sediments may serve as a potential source of contamination.

Trace metals in Chun-su Bay sediments (천수만 퇴적물에서 미량금속의 지화학적 특성)

  • Song, Yun-Ho;Choi, Man-Sik;Ahn, Yun-Woo
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.4
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    • pp.169-179
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    • 2011
  • To investigate the controlling factor and accumulation of trace metal concentrations in Chun-su Bay sediments, grain-size, specific surface area, organic carbon content, calcium carbonate content, and concentration of Al, Fe, Na, K, Mg, Ca, Ti, Mn, P, S, Ba, Sr, Li, Co, Cr, Ni, Cu, Zn, As, Cd, Cs, Sc, V, Sn were analyzed. Controlling factors of metals were quartz-dilution, calcium carbonate and coarse sand or K-feldspar. Although the distribution of V, Co, Cr, Ni, Cu, Zn, Sn, and Cd concentration was explained by grain-size effiect, Mn and As showed the similar importance of grain-size effect and coarse sand or K-feldspar factors. By virtue of enrichment factor and 1 M HCl experiment, there were little enrichment in all the trace metals in bay sediments, which were explained well by geochemical properties of sediments. Since the concentration levels of As in coarse sand were high as much as those in fine-grained sediments and it was combined with Mn oxide (1 M HCl leached) and K-feldspar (residual), it was suggested that when the enrichment of As in sediments would be assessed, it is necessary to separate the coarse sand from bulk sediments or to use only sediments with higher than 10% in < $16{\mu}m$ fraction.

Geochemical Composition of Volcanic Ash from Historical Eruptions of Mt. Baekdu, Korea (역사시대에 분화한 백두산 화산재의 화학 성분)

  • Yun, Sung-Hyo;Koh, Jeon Seon;Chang, Cheolwoo
    • The Journal of the Petrological Society of Korea
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    • v.27 no.1
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    • pp.37-47
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    • 2018
  • Volcanic ash samples of historical eruptions from Mt. Baekdu were analyzed for major oxides, trace and rare earth elements by a variety of analytical techniques. The results indicate that the ashes consist of approximately 58.8~71.1 wt.% $SiO_2$, 9.6~16.8 wt.% $Al_2O_3$, 4.5~6.9 wt.% $Fe_2O_{3t}$, 0.1~1.7 wt.% MgO, 0.3~1.6 wt.% CaO, 5.2~6.3 wt.% $Na_2O$, 4.3~5.9 wt.% $K_2O$ and less than 1.2 wt.% $TiO_2$. Thirty two trace metals including Ba, Cu, Cr. Co, Ni, Sr, V, Zn, and Zr were analyzed. The ashes can be divided two groups: group A(1 ka Millennium pumice, 1668 and $190{\underline{3}}$ pumice) and group B(1702 pumice) according to the relative enrichment of HREEs. The abundances of heavy metals such as Cu, Co, Mn, and Zn were relatively low. As compared to the Sakurajima volcanic ash, Baekdusan volcanic ash has low concentrations of Y, Nb, Pb, U, Sc, V, Ni and Cu and high concentrations of Zr, Ba, Hf, Cr, Co, Zn and rare-earth (except Eu).