• Title/Summary/Keyword: IrMn

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Elemental Correlations of Chemical Compositions in Co-rich Mn-crusts of the Republic of Marshall Islands (마샬공화국 고코발트망간각 화학조성의 원소 상관관계)

  • 황의덕;장세원;김두영
    • Journal of the Mineralogical Society of Korea
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    • v.12 no.2
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    • pp.77-90
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    • 1999

  • Characteristics and variations of chemical compositions in Co-rich crusts occurred in the EEZ of the Republic of Marshall Islands were reviewed. Correlation coefficient analysis, hierarchical cluster analysis, and Q-mode factor analysis for 62 samples were done in this study. All data were selected and gathered from the open file report of the cooperative cruise done by United States Geological Survey with Scripps Institute of Oceanography, University of Hawaii or Korea Ocean Research Development Institute. The average of crust thickness. Co content, and Ni content of 62 samples from the 21 seamounts were 30mm, 0.58 wt% and 0.40%, respectively. The mineral phases and associated elements assigned by correlation coefficients, cluster analysis and Q-mode factor analysis are following four. 1) CFA: P, Ca, CO2, Y, Sr: 2) Mn-oxide mineral: As, Mn, Co, Na: 3) Al-silicate mineral: Pd,Si, Al, Cu, Fe: 4) PGE-bearing mineral: Rh, Pt, Ir.

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Syntheses of Biologically Non-Toxic ZnS:Mn Nanocrystals by Surface Capping with O-(2-aminoethyl)polyethylene Glycol and O-(2-carboxyethyl)polyethylene Glycol Molecules

  • Kong, Hoon-Young;Song, Byung-Kwan;Byun, Jonghoe;Hwang, Cheong-Soo
    • Bulletin of the Korean Chemical Society
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    • v.34 no.4
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    • pp.1181-1187
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    • 2013

  • Water-dispersible ZnS:Mn nanocrystals were synthesized by capping the surface of the nanocrystal with O-(2-Aminoethyl)polyethylene glycol (PEG-$NH_2$, Mw = 10,000 g/mol) and O-(2-Carboxyethyl)polyethylene glycol (PEG-COOH, Mw = 10,000 g/mol) molecules. The modified PEG capped ZnS:Mn nanocrystal powders were thoroughly characterized by XRD, HR-TEM, EDXS, ICP-AES and FT-IR spectroscopy. The optical properties were also measured by UV/Vis and photoluminescence (PL) spectroscopies. The PL spectra showed broad emission peaks at 600 nm with similar PL efficiencies of 7.68% (ZnS:Mn-PEG-NH2) and 9.18% (ZnS:Mn-PEG-COOH) respectively. The measured average particle sizes for the modified PEG capped ZnS:Mn nanocrystals by HR-TEM images were 5.6 nm (ZnS:Mn-PEG-NH2) and 6.4 nm (ZnS:Mn-PEG-COOH), which were also supported by Debye-Scherrer calculations. In addition, biological toxicity effects of the nanocrystals over the growth of wild type E. coli were investigated. They showed no biological toxicity to E. coli until very high concentration dosage of 1 mg/mL of the both nanocrystal samples.

  • https://doi.org/10.5012/bkcs.2013.34.4.1181 인용 PDF KSCI