• ETRI Journal
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• v.10 no.3
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• pp.242-246
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• 1988

반도체 소자에서 $N^+$ 접합에 이용되는 As 이온주입된 시편을 RBS(Rutherford backscattering spectrometry)법으로 분석하였다. Random 스펙트럼으로부터 $R_p$, $\DeltaR_p$, As의 최대농도를 구하고 channeled 스펙트럼으로부터 이온 주입에 의한 결정 손상층의 두께와 열처리 후 interstitial site에서 substitutional site로 치환된 As의 비를 구하였다.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.10a
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• pp.180.1-180
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• 2003

• 전기의세계
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• v.45 no.2
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• pp.32-38
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• 1996

본 논문에서는 2차측이 평판형 구조를 갖는 선형유도전동기를 대상으로 하여 유한요소법을 이용한 수치해석방법과 기자력발생의 개념적인 기본단위가 되는 하나의 전류도체를 등가표면전류밀도로 치환하여 해석하는 공간고조파해석 방법[10]과, 영구자석 계자형 선형동기전동기의 공간고조파 해석방법에 대하여 소개하겠다.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.301-309
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• 2008

In this study, the effect of formaldehyde to phenol (F/P) molar ratios, catalyst wt%, and reaction temperature on the chemical structure was studied utilizing a two-level full factorial experimental design. The effect of three variables on the chemical structure was analyzed by using three-way ANOVA of SPSS. Concentration of methyrol-substituted phenols after 300 min addition reaction increased with higher the F/P mole ratio, lower the reaction temperature and lower the catalyst wt%. Resol catalysed by barium hydroxide showed higher addition of formaldehyde onto ortho positions of phenolic rings. A simplified elementary reaction model for resole type phenolic resin formation which do not consider the dissociation of phenolic compounds and the fraction of formaldehyde in the form of methylene glycol was proposed and compared with Zavitsas' type models. Elementary reaction model showed error of 2.79% compared to the error of 3.27% in Zavitsas' type models. It was thought that the elementary reaction model could be used to predict the behavior of addition reaction in resol formation.

• Journal of the Korean Chemical Society
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• v.20 no.5
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• pp.380-390
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• 1976

The trends of forming a charge transfer complex have been studied for electron donors such as anisole, 4-chloroanisole, 2,4-dichloroanisole, 2-fluoro-4-chloroanisole, 2-bromo-4-chloroanisole, 2-iodo-4-chloroanisole, 2-fluoro-4,6-dichloroanisole, 2,4,6-trichloroanisole, 2-bromo-4,6-dichloroanisole, 2-iodo-4,6-dichloroanisole, and 2-iodo-4,5,6-trichloroanisole, and electron acceptors such as iodine and iodine monochloride in the carbon tetrachloride or the hexane solvent system. It was found that the formation of a charge transfer complex was influenced by the Van der Waals Radii of the 2-halogen atoms on the benzene ring and further the overall steric moiety of the molecule of the electron donor. These trends were also experienced in a system of chloroform and one of the prementioned electron donor by means of a nuclear magnetic resonance spectrometry. The spectrophotometrical data on the formation of the charge transfer complex were presented and the results were discussed with views of the steric structure of the 2-halogen atom on the benzene ring.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.157-164
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• 2016

In this research, based on the condition of using desulfurization gypsum(FGD) as a stimulator for high-volume blast furnace slag cement mortar, sieving and heating process methods of removing activated carbon in FGD were compared with the non-processed FGD and recycled and natural fine aggregates were compared for suitable aggregate to be used. According to the result of experiment, sieving with 0.3mm was more efficient than $500^{\circ}C$ heating for processing the FGD, and recycled fine aggregate showed more favorable result than natural fine aggregate at the FGD content was 5 to 10%. On the other hand, the mortar mixture including recycled fine aggregate had a high drying shrinkage, and absorption ratio, and thus specific limitations on applying recycled fine aggregate should be required.

• Analytical Science and Technology
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• v.20 no.5
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• pp.406-412
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• 2007

The formation of inclusion complexes between ${\beta}$-cyclodextrin and diethylenetriamine substituted-pyridine copper(II) perchlorate; [Cu(dien)(sub-py)] $(ClO_4)_2$, were studied by spectrophotometric methods. On account of charge-transfer band(MLCT) and $^2T_2{\rightarrow}^2E$, the two high peaks were observed as an inclusion complex for the [${\beta}$-CD]$[Cu(dien)(p-Cl-py)]^{2+}$ in the ultraviolet region of the spectrum. The ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion formed a 1:1 complex, and the formation constants were decreased with the increasing temperatures, due to weak binding energy between ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion. This reaction was controlled by enthalpy. In a correlation of the Hammett substituent constants and formation constants for the reaction, formation constants were increased by strong binding energy in the inclusion complexes when electron donating groups were substituted in pyridine ring.

• Journal of the Korean Chemical Society
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• v.31 no.5
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• pp.464-470
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• 1987

7-Substituted 2-aminophenazine-5,10-dioxides were synthesized by the reaction of 4-aminophenol with 6-substituted benzofuroxan derivatives which had been obtained from aniline derivatives bearing methoxy, methyl, acetyl, and nitro group at the para position. 2-Aminophenazine-5,10-dioxide was also prepared by the reaction of 4-aminophenol with benzofuroxan. The antimicrobial activities of these phenazine dioxide derivatives were investigated in terms of minimum inhibitory concentration by the common twofold dilution technique. It was observed that the antimicrobial activity of the phenazine dioxides bearing electron releasing substituents was stronger than that of those bearing electron withdrawing substituents. From this result, it was concluded that the antimicrobial activity of phenazine dioxide derivative has a direct relationship with the electronic effect of the substituents.

• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.51-56
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• 1992

X-ray diffraction analysis and infrared spectrophotometry were used to investigate the crystal structures and the bonding characteristics in $Pb(Zr_{1-y}Ti_y)O_3$ (PNZT), which has a perovskite structure. As $Pb^{2+}$ of PZT was substituted by 8${\sim}$12 atom% $Nd^{3+}$ ion, the structures were changed to cubic from tetragonal and its transmission had maximum value. Transmission increased as the stretching force constant $(k_s)$ of unit cell increased. It is supposed that the electro-optic characteristics might occur due to electron-transition from HOMO to LUMO of titanium ion.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.517-520
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• 2008

In this study, corrosion resistance of steel in cracked-reinforced concrete was performed according to experimental method. Mixed design is OPC, 30% PFA, 60% GGBS and 10% SF, respectively. Moreover, corrosion resistance test was measured using ultra testing machine for 0.3mm crack induction. The corrosion resistance of blended concrete shows the results following OPC > 10%SF > 30% PFA > 60% GGBS after 60days curing. In case of mass loss test, embedded reinforcement in OPC concrete surveyed the minimum corrosion and appeared better corrosion resistance than blended concrete. As a result, corrosion resistance of sound concrete is higher than cracked concrete. Moreover, corrosion resistance of binary concrete is lower than OPC.