• Title, Summary, Keyword: Eu

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Electron Magnetic Resonance of Eu2+ in SrCl2:Eu Single Crystal

  • Lee, Soo Hyung;Yeom, Tae Ho;Kim, Sung-Hwan
    • Journal of Magnetics
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    • v.17 no.4
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    • pp.251-254
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    • 2012
  • The electron paramagnetic resonance (EPR) of the $Eu^{2+}$ ion in $SrCl_2$:Eu single crystal has been investigated using an X-band spectrometer. The angular dependence of magnetic resonance positions for the $Eu^{2+}$ impurity ion in the crystallographic aa-plane is analyzed with effective spin-Hamiltonian. The EPR spectra of the isolated $Eu^{2+}$ center merged to each other. The hyperfine splitting of the isolated $Eu^{2+}$ center due to the $^{151}Eu$ nucleus is approximately 35 G. Three kinds of $Eu^{2+}$ centers except the isolated $Eu^{2+}$ center, $Eu^{2+}$ pairs, $Eu^{2+}$ triples, and other $Eu^{2+}$ clusters, are split from the fitting of the integrated experimental spectrum with the Gaussian curve. The calculated spectroscopic splitting parameters of the $Eu^{2+}$ pairs, $Eu^{2+}$ triples, and other $Eu^{2+}$ clusters in $SrCl_2$:Eu crystal are $g_1$ = 2.06, $g_2$ = 1.94, and $g_3$ = 1.93, respectively.

Investigation of Eu(Ⅲ)-Polyfunctional Organic Acid Complexes by Eu(Ⅲ) Luminescence Spectroscopy (Eu(Ⅲ) 발광 분광법을 이용한 Eu(Ⅲ)과 다가 유기산 착물 연구)

  • Lee, Byoung Ho;Shin, Hyun Sang;Moon, HiChung
    • Journal of the Korean Chemical Society
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    • v.40 no.1
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    • pp.59-64
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    • 1996
  • The 7F0→5D0excitation spectra of Eu(Ⅲ) complexed with polyfunctional monocarboxylic acid(glycolic acid, glycine and thioglycolic acid) containing a terminal O, N and S neutral donors and propionic acid were investigated using Eu(Ⅲ) luminescence spectroscopy. In the excitation spectra of Eu(Ⅲ)-propionate system, the stepwise appearance of the peaks was observed at 579.0, 579.2 and 579.5 nm with increasing in the ligand-to-metal ratio, which correspond to the formation of Eu(propionate)2+, Eu(propionate)2+ and Eu(propionate)3 species. Three maximum peaks were also obtained for Eu(Ⅲ)-glycolate, Eu(Ⅲ)-glycinate and Eu(Ⅲ)-thioglycolate systems and were found to be quite similar to those of Eu(Ⅲ)-propionate system. The q values (number of coordinated water molecules of Eu(Ⅲ) ion) obtained from the luminescence decay constants of Eu(Ⅲ)-glycolate and Eu(Ⅲ)-thioglycolate were 7.0 and 7.1, and compare well with 7.3 for Eu(Ⅲ)-propionate: Each ligand units replace around two coordinated water molecules. These results show that the polyfunctional monocarboxylates behaves like the propionate for Eu(Ⅲ) ion coordination.

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Determinants of the EU's Antidumping Measure against Korean products (EU의 한국산 제품에 대한 반덤핑 조치에 영향을 미치는 거시경제요인 분석)

  • Hu, Di;Choi, Chang-Hwan
    • International Commerce and Information Review
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    • v.15 no.3
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    • pp.245-262
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    • 2013
  • The transaction size between South Korea and the European Union (EU) had increased by more than two times among 2003 to 2008. With rapid growth of transaction, the EU was becoming important transaction object of South Korea gradually. EU has used the Antidumping policy as a trade protection tool against Korean products due to reduce the deficit of trade balance of payment, boost the economic growth and protect its weak industries. This paper investigates whether there is a connection between the EU's macroeconomic activity and pressures for protection to Korean products under antidumping measures with using the current data that come from the WTO, World Bank for 2004 to 2012. The result suggests that pressures for protection under Antidumping measure against exporting of Korean products to EU have increased during periods of macroeconomic weakness of low GDP growth, larger deficit of trade balance, however, has not significantly affected during periods of high unemployment.

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Photoemission study f valence stated in Eu chalcogenides

  • Hoon Koh;Park, Won-Go;Oh, S.J.
    • Proceedings of the Korean Vacuum Society Conference
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    • pp.166-166
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    • 2000
  • We studied electronic structure of magnetic semiconductors EuO, EuS, and EuTe. The photoemission spectra show localized Eu 4f states and broad anion p bands. As the size of anion increases from oxygen to tellurium, anion p band width increases and eventually overlaps Eu 4f states. Hence in EuO and EuS, Eu 4f states are the highest occupied stated lying above anion p band, while Te 5p band spreads widely over Eu 4f states to become valence band maximum in EuTe. It was also observed that Eu 4f states have width of 0.7eV and dispersion of 0.2eV in EuS by angle resolved photoemission spectroscopy. The width of the 4f spectra mainly originates from atomic multiplets, but the much larger dispersion than that of Eu metal is due to p-f mixing.

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Sulfurization Reaction Characteristics of Eu-doped Uranium Oxides (유로퓸 고용(固溶) 우라늄산화물(酸化物)의 황화반응(黃化反應) 특성(特性))

  • Lee, Jae Won;Park, Geun Il;Lee, Jung Won
    • Resources Recycling
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    • v.22 no.3
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    • pp.57-64
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    • 2013
  • Sulfurization reaction characteristics of $Eu_2O_3$, uranium oxides($UO_2$, $U_3O_8$), mixture of $Eu_2O_3$ and uranium oxides, Eu-doped uranium oxides($(U,Eu)O_2$, $(U,Eu)_3O_8$), and phase-separated products prepared by HOX (High temperature OXidation) of $(U,Eu)O_2$ were investigated in the temperature range from 400 to $800^{\circ}C$. Only $Eu_2O_3$ in the mixture of $Eu_2O_3$ and uranium oxides was converted into $Eu_3S_4$ by sulfurization reaction at $450^{\circ}C$ without reaction between them. Sulfurization reaction behavior of $(U,Eu)_3O_8$ and $(U,Eu)O_2$ up to $600^{\circ}C$ was similar to $U_3O_8$ and $UO_2$, respectively, while they were sulfurized into Eu-rich $(U,Eu)S_x$ and ${\alpha}-US_2$ at $800^{\circ}C$. In the sulfurization of RE-rich $(U,Eu)_4O_9$ and $U_3O_8$ prepared by high temperature oxidation, it was confirmed that RE-rich $(U,Eu)S_x$ and UOS phases were formed at $600^{\circ}C$. For Eu-rich $(U,Eu)O_2$ and $UO_2$ prepared by reduction of HOX products, it was identified that Eu-rich (U,Eu)OS was formed at $450^{\circ}C$ by sulfurization of Eu-rich $(U,Eu)O_2$, while $UO_2$ remained unreacted.

A Study on Process Models for Proposal Evaluation of R&D EU Government Support Programmes (EU정부의 R&D지원 제안서평가 프로세스모형에 관한 연구)

  • Kim, Jin Suk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.1
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    • pp.80-84
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    • 2013
  • The EU in order to surpass the United States in the world economy have tried several aspects. Economic growth is possible through the technological competitiveness of this industry, and also through the development of industrial technology and employment. Such EU Commission has taken several support policies in order to raise the R & D capabilities. Non-EU member countries, Korea, R & D pipe central incisor see support for the policy proposal evaluation for women is important. The aim of this paper is to analyze the proposal evaluation process of the EU commission for R&D projects. I argue that the EU's methode of proposal evaluation for EU R&D consists of five stages: expert briefings, proposals for individual assessment, consensus and finally a panel evaluation. The main features of the EU's R&D evaluation process for proposals are experts and panel evaluation. The Korean government could select, operate and manage experts for the EU's R&D evaluation. That would lead to a higher rate of success for Korean proposals in the EU.

A Study on EU Anti-dumping Law (EU 반덤핑법에 관한 소고)

  • Kim, Do-Hyoung
    • Management & Information Systems Review
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    • v.21
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    • pp.77-98
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    • 2007
  • This thesis is related with Anti-dumping law about Korea's export in EU. Indeed, Korea' export to EU market is how related to EU's Anti-dumping law this study was intended to reveal from a legal point of view. For this purpose from EU's Anti-dumping law's institution at present to application historical channel was examined and is showed Anti-dumping law's application procedure briefly. Throughout this study what we could get are EU's Anti-dumping law based on a statute, EU's Anti-dumping law's institution background and the law's application procedure & effects.

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A Study of the International Dispute on EU ETS Aviation Directive (EU ETS 항공 부분 지침에 따른 국제 분쟁에 관한 소고)

  • Hur, Yun-Seok;Pak, Myong-Sub;Woo, Jung-Wouk;Youn, Jae-Woong
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.54
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    • pp.261-282
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    • 2012
  • The European Union (EU) has introduced the EU Emissions Trading Scheme (EU ETS) as one of the key policies to reduce the level of greenhouse gas emissions and in July 2008, they decided to include aviation in the scheme. As soon as the decision was announced the EU ETS was met by sharp opposition from world governments and international aviation. A group of US airlines, in particular, dropped a lawsuit against the British government over aviation's inclusion in the EU ETS. On 21 December, the Court of Justice of the European Union (CJEU) ruled that aviation's inclusion in the EU ETS which covers all flights arriving into and departing from the EU is legal and does not contravene international law. The scheme eventually came into effect on 1 January 2012. However, most countries are in opposition to the EU ETS and have agreed on counter-measures to undermine the EU's plan which may bring chaos to the aviation industry if such measures were to put into practice. This study therefore will analyze the likely effects that may be brought to the Korean aviation industry as a result of the inclusion of aviation in the EU ETS. Further, it hopes to contribute to the Korean aviation industry by studying other countries' counter-measures in advance.

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Luminescent characteristics with coupling structure of Eu for ZnO:Eu Phosphor (Zno:Eu 형광체의 Eu 결합 구조에 따른 발광 특성)

  • 박용규;한정인;조황신;주성후
    • Electrical & Electronic Materials
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    • v.10 no.8
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    • pp.763-769
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    • 1997
  • In this study we have synthesized Zno:Eu phosphors under various sintering atmospheres and temperatures. The analysis of X-ray diffractometer measurement indicates that for Zno:EuCl$_3$ phosphors sintered in air and vacuum 뗘 exists in the host lattice as Eu$_2$O$_3$and EuOCl respectively. From the photoluminescence for the phosphors sintered in vacuum Eu removes the broad-band emission of the ZnO host consequently isolating the red emission due to Eu$^{3+}$ ion and improves the color purity of red emission. The photoluminescence excitation and time resolving spectrum measurements suggest that energy-transfer process occurres from the self-activated defect center in ZnO host the Eu$^{3+}$ ion which exist in the host lattice in the form of EuOCl.

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Growth and magnetic properties of Tb, Eu, EuTb-substituted garnet single crystal films (Tb, Eu, EuTb가 치환된 가네트 단결정 막의 성장과 자기적 특성)

  • Kim G. Y;Yoon S. G.;Chung I. S;Park S. B;Yoon D. H
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.14 no.5
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    • pp.193-198
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    • 2004
  • Using the $PbO-B_2O_3-Bi_2O_3$ flux system, $(TbBi)_3(FeAIGa)_5O_{12}(TbIG)$, $(EuBi)_3(FeAIGa)_5O_{12}(EuIG)$ and $(EuTbBi)_3(FeAIGa)_5O_{12}(EuTbIG)$ films were grown on $(GdCa)_3(GaMgZr)_5O_{12}(SGGG)$ substrates by the liquid phase epitaxy (LPE). The saturation magnetization of the grown TbIG, EuIG and EuTbIG films was about 150, 950 and 125 Oe, respectively. The TbIG films resulted in the single magnetic domain while the EuIG and EuTbIG films were observed to be the multi magnetic domains by magnetic force microscope (MFM).