• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.82-89
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• 1989

The fluorescence of $Eu^{3+},\;Tb^{3+}$ substituted for $La^{3+}$ in Lanthanum Oxychloride (LaOCl) has been studied. The fluorescence intensity of the $Eu^{3+},\;Tb^{3+}$ in LaOCl excited by Ultra-violet light were investigated on its activator concentration and discussed as the energy transfer process. The energy transfer from $Tb^{3+}\;to\;Eu^{3+}$ take place in the $Eu^{3+}\;and\;Tb^{3+}$ codoped LaOCl crystal. This process was confirmed to the change of concentration and the measurement of fluorescence decay time.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.3
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• pp.353-366
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• 2021

The solubilities of different multicomponent lanthanide oxide (Ln₂O₃) solid solutions including binary (Ln₁ and Ln₂ = La, Nd, Eu, or Tm), ternary (Ln₁, Ln₂, and Ln₃ = La, Nd, Eu, or Tm), and higher systems (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) were studied after aging for four weeks at 60℃. Our recent study revealed that the phase transformations in binary ((La, Nd) and (La, Eu)) and ternary (La, Nd, Eu) systems are responsible for the formation of (La, Nd)(OH)₃, (La, Eu)(OH)₃, and (La, Nd, Eu)(OH)₃ solid solutions, respectively. The variations in the mole fractions of La³⁺, Nd³⁺, and Eu³⁺ in the sample solutions of these hydroxide solid solutions indicated that a thermodynamic equilibrium might account for the apparent La, Nd, and Eu solubilities. Conversely, the binary and ternary systems containing Tm₂O₃ as the heavy lanthanide oxide retained the oxide-based solid solutions, and their solubility behaviors were dominated by their congruent dissolutions. In the higher multicomponent system, the X-ray diffraction patterns of the solid phases, before and after contact with the aqueous phase indicated the formation of a stable oxide solid solution and their solubility behavior was explained by its congruent dissolution.

• Journal of Contemporary Eastern Asia
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• v.19 no.2
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• pp.234-263
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• 2020

This study aims to assess the quality of the EU's public diplomacy efforts through social media. Specifically, this research explores the headquarters of European public diplomacy (European External Action Service, EEAS) and its subordinate agent (EU Delegation to South Korea, EUDK). The main research question is "how coherently and effectively does the EU execute public diplomacy strategies in the third countries?'' This study employs both quantitative and qualitative approaches―the former for the results presentation and the latter for the results interpretation. The results are summarized in two points. First, both the EEAS and the EUDK maintained an objective position by posting only neutral perspectives on their social media. Second, the narratives of the main actors were the same, but the main themes were different according to their contexts. The analysis discusses the effectiveness of the EU's strategic narratives by focusing on measuring message reception. Its limited findings were that social media postings could not induce the audiences' active discussion of the EU's diplomatic performances. The conclusion suggests that the EU should identify the expectations from its global counterparts and use these to forge the Union's strategic narratives.

• Analyses & Alternatives
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• v.8 no.1
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• pp.5-31
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• 2024

The US-led and European partners supporting liberal international order has dwindled. A number of research has been conducted to explore reasons, starting point, the possibility of resurrection, and even the future scenarios of the international order. This is particularly important for the EU, in that the EU was built for a world that is peaceful, multilateral and driven by compromise inseparable from the liberal international order. The current situation of the crisis in the international order is also important to emerging powers notably China and Russia which seek for a new order best suitable for their own interests. In this sense, this paper explains the significance of the liberal international order to the EU, the necessity of salvaging an order or creating a new order, and important variables - elections held in 2024 across the EU, in the European Parliament, and the US, Russia's invasion of Ukraine, trans-atlantic partnership and EU-China relations - which possibly affect the EU to establish a new European order. In fact, the EU is unlikely to take the lead in forming a new international order. Nonetheless, the first task the EU should do is to acknowledge the crisis situation at present and to make a decision of the EU's position and role regarding saved, reformed or newly shaped order.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.1
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• pp.46-54
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• 2014

This study was conducted to investigate the effects of eucalyptus (E. Camaldulensis) crude oils (EuO) supplementation on voluntary feed intake and rumen fermentation characteristics in swamp buffaloes. Four rumen fistulated swamp buffaloes, body weight (BW) of $420{\pm}15.0$ kg, were randomly assigned according to a $2{\times}2$ factorial arrangement in a $4{\times}4$ Latin square design. The dietary treatments were untreated rice straw (RS) without EuO (T1) and with EuO (T2) supplementation, and 3% urea-treated rice straw (UTRS) without EuO (T3) and with EuO (T4) supplementation. The EuO was supplemented at 2 mL/h/d in respective treatment. Experimental animals were kept in individual pens and concentrate mixture was offered at 3 g/kg BW while roughage was fed ad libitum. Total dry matter and roughage intake, and apparent digestibilites of organic matter and neutral detergent fiber were improved (p<0.01) by UTRS. There was no effect of EuO supplementation on feed intake and nutrient digestibility. Ruminal pH and temperature were not (p>0.05) affected by either roughage sources or EuO supplementation. However, buffaloes fed UTRS had higher ruminal ammonia nitrogen and blood urea nitrogen as compared with RS. Total volatile fatty acid and butyrate proportion were similar among treatments, whereas acetate was decreased and propionate molar proportion was increased by EuO supplementation. Feeding UTRS resulted in lower acetate and higher propionate concentration compared to RS. Moreover, supplementation of EuO reduced methane production especially in UTRS treatment. Protozoa populations were reduced by EuO supplementation while fungi zoospores remained the same. Total, amylolytic and cellulolytic bacterial populations were increased (p<0.01) by UTRS; However, EuO supplementation did not affect viable bacteria. Nitrogen intake and in feces were found higher in buffaloes fed UTRS. A positive nitrogen balance (absorption and retention) was in buffaloes fed UTRS. Supplementation of EuO did not affect nitrogen utilization. Both allantoin excretion and absorption and microbial nitrogen supply were increased by UTRS whereas efficiency of microbial protein synthesis was similar in all treatments. Findings of present study suggested that EuO could be used as a feed additive to modify the rumen fermentation in reducing methane production both in RS and UTRS. Feeding UTRS could improve feed intake and efficiency of rumen fermentation in swamp buffaloes. However, more research is warranted to determine the effect of EuO supplementation in production animals.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.347-357
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• 2018

The applicability of room temperature ionic liquids (RTILs), 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([$C_nmim$] [$Tf_2N$]), was investigated for the extraction of Am(III) and Eu(III) from nitric acid using n-octyl(phenyl)-N,N-diisobutyl carbamoylmethyl phosphine oxide (CMPO) and tri-n-butylphosphate (TBP) as extractants. The distribution ratios of Am(III) and Eu(III) in CMPO-TBP/[$C_nmim$][$Tf_2N$] were measured as a function of various parameters such as the concentrations of nitric acid, CMPO, and TBP. The results were compared with those obtained in CMPO-TBP/n-dodecane (n-DD). With comparable concentrations of the extractants, the distribution ratios obtained with RTILs were much higher than those obtained with n-DD. It was observed that the extraction efficiency was less for Eu(III) than for Am(III). The extraction of Am(III) and Eu(III) decreased with increases in the feed acidity for all three RTILs. The results suggest that the extraction of Am(III) and Eu(III) by CMPO in RTILs from nitric acid proceeds through the cation-exchange mechanism. The distribution ratios of Am(III) and Eu(III) increased with increases in the concentration of CMPO for all three RTILs. A linear regression analysis of the extraction data resulted in a straight line with a slope of about 3, suggesting the involvement of 3 molecules of CMPO during the extraction process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6599-6603
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• 2014

Strengthening the competitiveness of Korean Industrial Technology with cooperation from EU enterprises is very important. With regard to the technological cooperation Framework Program (FP) from the EU during the period, 2007 to 2013, the most active participants involved were Germany, England and France. Additional participants were Russia, China, India, and Brazil. Korean participation as a non-EU Member State in this program was low. The aim of this study was to determine effective activation strategies for FP participation by Korean enterprises and institutions. Chapter 2 reports the theoretical background. Chapter 3 presents the methodology of the study. Chapter 4 describes the $8^{th}$ FP of the EU in detail. Chapter 5 attempts to find a solution for the optimal participation of Korean firms and institutions in the 8th FP of the EU. Through this paper, a solution for $8^{th}$ FP can be found: many Korean enterprises are unaware of the FP. Therefore, it is of the utmost importance to provide information about the characteristics and processes regarding the EU $8^{th}$ FP.

• Journal of the Korean Magnetics Society
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• v.15 no.4
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• pp.246-249
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• 2005

The blue-color emitting phosphor powder, $CaMgSi_{2}O_6:Eu^{2+}(CMS:Eu^{2+})$ was synthesized by the solid-state reaction method. The synthesized powder was annealed from room temperature to $1,100^{\circ}C$ in air. Its PL property and valence state of Eu atoms was measured by the photoluminescence (PL) and the electron paramagnetic resonance (EPR) spectrometers, respectively. The PL intensity was stable to $700^{\circ}C$, but drastically decreased to $1,100^{\circ}C$. The behavior of EPR intensity was very similar to the PL intensity. The EPR measurement showed that decreased intensity of the PL was caused to the oxidation from the ion $Eu^{2+}$ to $Eu^{3+}$ ions. The EPR spectrometer was powerful as a tool that could distinguish between the valence states of Eu atom as a dopant in various phosphors.

• Applied Chemistry for Engineering
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• v.8 no.6
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• pp.1006-1013
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• 1997

This study was carried out to elucidate the chemical characteristics of mutual separation for Am and Eu, which were selected as a stand-in from minor actinide and rare earth elements, by solvent extraction with di-(2-ethylhexyl)phosphoric acid containing zirconium at batch system. As results, 92.3% of Am and 99.1% of Eu were coextracted with 1M DEHPA/n-dodecane containing zirconium (Zr $concentration=8.7g/{\ell}$) at 0.5M $HNO_3$ in the extraction step. The extraction yields of Am and Eu were proportionally increased with the concentration of Zr in Zr salt of 1M DEHPA/n-dodecane having the synergistic effect. In the lst stripping step for the selective separation of Am, 38.1% of Am and 3% of Eu were stripped with the mixed solution of 0.05M DTPA and 1M lactic acid adjusted pH of 3.0. At that time, the separation factor calculated from the distribution coefficients of Am and Eu was 14.2. In the 2nd Stipping step to remove the Eu remained the organic phase after the lst stripping step, 94.4% 0f Eu was stripped into aqueous phase with 6M $HNO_3$.

• International Commerce and Information Review
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• v.15 no.4
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• pp.125-145
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• 2013

The Korea-EU FTA will provide korea with a significant advantage in the region both international trade and consumer welfare. Under the Korea-EU FTA, increasing of bilateral trade in consumer and industrial products would become duty and most remaining tariffs would be eliminated. This article studies on EU product price level of Korean consumer for before and after Korea-EU FTA effectuation. The questionnaires are sended 1,000 samples and 780 returns, 283 of them are analyzed for a this study. This paper has there main a parts, A Paired Samples Test result shows that the EU goods price level are positively affected by Flesh-meat, Electronic device & Electric home appliances, Kitchen utensils, Fruit juice(beverage), alcoholic liquors(wine, whisky), Clothes & Fashion. However, The Clothes & Fashion does not affect in EU goods price level, the Clothes & Fashion positively affected price differential more FTA effectuation before than FTA effectuation after.