글리신-질산염 연소법으로 합성된 SrAl₂O₄:Eu²⁺,Dy³⁺ 형광체의 발광 및 장잔광 특성

이영기,김정열,이유기,Lee, Young-Ki,Kim, Jung-Yeul,Lee, You-Kee 한국재료학회 2010 한국재료학회지 Vol.20 No.7

A $SrAl_2O_4:Eu^{2+},Dy^{3+}$ phosphor powder with stuffed tridymite structure was synthesized by glycine-nitrate combustion method. The luminescence, formation process and microstructure of the phosphor powder were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectroscopy (PL). The XRD patterns show that the as-synthesized $SrAl_2O_4:Eu^{2+},Dy^{3+}$ phosphor was an amorphous phase. However, a crystalline $SrAl_2O_4 $ phase was formed by calcining at $1200^{\circ}C$ for 4h. From the SEM analysis, also, it was found that the as-synthesized $SrAl_2O_4:Eu^{2+},Dy^{3+}$ phosphor was in irregular porous particles of about 50 ${\mu}m$, while the calcined phosphor was aggregated in spherical particles with radius of about 0.5 ${\mu}m$. The emission spectrum of as-synthesized $SrAl_2O_4:Eu^{2+},Dy^{3+}$ phosphor did not appear, due to the amorphous phase. However, the emission spectrum of the calcined phosphor was observed at 520 nm (2.384eV); it showed green emission peaking, in the range of 450~650 nm. The excitation spectrum of the $SrAl_2O_4:Eu^{2+},Dy^{3+}$ phosphor exhibits a maximum peak intensity at 360 nm (3.44eV) in the range of 250~480 nm. After the removal of the pulse Xe-lamp excitation (360 nm), also, the decay time for the emission spectrum was very slow, which shows the excellent longphosphorescent property of the phosphor, although the decay time decreased exponentially.

경제 교육 모형 설정을 위한 일연구

이영기,조영달 ( Young Kee Lee,Young Dal Cho ) 한국사회과교육학회 1984 시민교육연구 Vol.8 No.1

SrAl₂O₄:Eu⁺², Dy⁺³ 장잔광 형광체 합성에 있어서 알루미늄 화합물에 따른 열적거동 및 발광특성 변화

이영기,이유기,Lee, Young-Ki,Lee, You-Kee 한국재료학회 2007 한국재료학회지 Vol.17 No.11

Both photoluminescence and thermal characteristics for $SrAl_2O_4:Eu^{+2},\;Dy^{+3}$ phosphors synthesized with various aluminum compounds (${\alpha}-Al_2O_3$, ${\gamma}-Al_2O_3$, amorphous-$Al_2O_3$ and $Al(OH)_3)$ were investigated in this study. The formation temperature of the host $SrAl_2O_4$ crystal is changed by these various aluminum compounds, as a result of the different thermal decomposition temperature of $SrCO_3$ phase. Among these compounds, the amorphous-$Al_2O_3$ phase shows the lowest formation temperature of the host $SrAl_2O_4$ crystal. The PL emission and excitation spectra of $SrAl_2O_4:Eu^{+2},\;Dy^{+3}$ phosphor are not affected by these aluminum compounds. After the removal of the Xenon lamp excitation (360 nm), however, the excellent longphosphorescent property of the phosphor is obtained by the amorphous-$Al_2O_3$ phase, although the decay time for all phosphors decrease exponentially.

약수에서 분리한 Yersinia pseudotuberculosis의 병원성과 16S rDNA 분석에 의한 분자학적 분류

이영기,최성민,오수경,이강문,염곤,Lee, Young-Kee,Choi, Sung-Min,Oh, Soo-Kyung,Lee, Kang-Moon,Ryeom, Kon 한국미생물학회 2001 미생물학회지 Vol.37 No.1

In order to investigate the pathogenicity and development of differential identification technique in the Yersinia species and other entericbacteria, we isolated 5 strains of Y.pseudotuberculosis from spring water sites in Seoul. The biochemical characteristics of isolated strains revealed that indole, VP($25^{\circ}C$, $37^{\circ}C$), $H_2S$, phenylalanine, lysine, arginine, ornithine, gas from glucose, lactose, sucrose, sorbitol, oxidase and motility($37^{\circ}C$) were all negative and urease, glucose, mannitol, salicin, catalase and motility($25^{\circ}C$) were all positive. To detect the causative agent of pseudotuberculosis(Y.pseudotuberculosis), we carried out a study using a PCR with inv primers complementary to the pathogenic region and found that all strains were positive, this revealed that strains from spring waters were pathogenic. Also 16S rDNA for total 5 strains of Y. pseudotuberculosis were amplified and a stretch of approximately 1,450 nucleotides were sequenced and analyzed. The 16S rDNA nucleotide sequence homologies among Yersinia species ranged 97.5% to 100% and between Y.pseudotuberculosis and other entericbacteria they ranged 93.0% to 95.1%. The Phylogenetic tree generated from the sequence analysis of the 16S rDNA gene showed 3 coherent clusters that could be separated into Y.pseudotuberculsis strains, some Yersinia species strains and other entericbacteria strains. 서울시내 25개 자치구에 산재한 약수터에서 5주의 Yersinia pseudotuberculosis를 분리하여 생화학적 특성, 병원성의 유무 및 16S rDNA 분석을 실시하였다. 분리된 Y. pseudotuberculosis는 모두 병원성 유전자인 inv를 소유하고 있었으며, 16S rDNA를 증폭한 후 염기서열을 분석하여 NCBI Genbank에 등록된 다른 Yersinia 속 및 장내세균 등과 비교해 본 결과 Yersinia 속 등과는 97.5%에서 100%의 높은 상동성(Similarity)을 나타내었고, 다른 장내세균 등과는 93.0%에서 95.1%의 낮은 상동성을 나타내었다. 165 rDNA 염기서열을 기초로 계통수를 작성한 결과 크게 3개의 cluster를 형성하였는데 특히 Y.enterocolitica (Z49830)은 Y.pseudotuberculasis (Z21939)와의 상동성(97.7%)보다 Y.intermedia (X75279)와의 상동성(97.9%)이 더 높게 나타났으며, E. coli (Z83205)는 Proteus vulgaris (AJ233425) 와의 상동성(93.2%)보다 Salmonella enteritidis (U90318)와의 상동성(97.7%)이 더 밀접한 연관성을 나타내었다.

Al-Ti 혼합 분말 슬러리를 이용한 강의 알루미나이징처리 방법

이영기,김정열,이유기,Lee, Young-Ki,Kim, Jung-Yeul,Lee, You-Kee 한국재료학회 2009 한국재료학회지 Vol.19 No.4

In this study, we attempted to develop a convenient aluminizing process, using Al-Ti mixed slurry as an aluminum source, to control the Al content of the aluminized layer as a result of a one-step process and can be widely adopted for coating complex-shaped components. The aluminizing process was carried out by the heat treatment on disc and rod shaped S45C steel substrates with Al-Ti mixed slurries that were composed of various mixed ratios (wt%) of Al and Ti powders. The surface of the resultant aluminized layer was relatively smooth with no obvious cracks. The aluminized layers mainly contain an Fe-Al compound as the bulk phase. However, the Al concentration and the thickness of the aluminized layer gradually decrease as the Ti proportion among Al-Ti mixed slurries increases. It has also been shown that the Al-Ti compound layer, which formed on the substrate during heat treatment, easily separates from the substrate. In addition, the incorporation of Ti into the substrate surface during heat treatment was not observed.

직업유형에 의한 여가태도의 성향 분석

이영기(Young Kee Lee) 한국여가레크리에이션학회 1992 한국여가레크리에이션학회지 Vol.9 No.-

The purpose of this study is to estimate the leisure attitude based on to occupation type groups. Measuring the leisure attitude was structured on the three components ; cognitive components measuring the individuals a general knowledge and beliefs about leisure, affective components evaluating the individual`s feelings and the degree of liking or disliking of leisure, behavioral components measuring the individual`s past, present, and intended actions with regard to leisure activities, and experiences. In analyzing these three components respectively, I described the explanation of the relationship between these components. The total subjects participated in the study were 1239 : 607 male, 632 female all over the country. On the basis of the analyzed data, the following conclusions were drawn 1) The preference of the leisure attitude according to the occupation type ranked White collar, self management, no occupation ; student, housewife, blue collar orderly. 2) The subjects perceived the cognitive components the most positively and the behavioral components the lowest and as a result they perceived it negatively. 3) Cognitive and affective components were shown significant differences but behavioral component was nothing. 4) In influence of the leisure attitude, the three components were comparatively much influenced by occupation type.

노인 치료레크리에이션의 지도방향 설정

이영기(Young Kee Lee) 한국사회체육학회 2000 한국사회체육학회지 Vol.13 No.-

The purpose of this study is to establish the leadership direction of therapeutic recreation of the elderly for recreation leaders. According to above mentioned, the results of study can be described as the following. First, for the setting up of the leadership direction about therapeutic recreation of the elderly, recreation leaders have to understand the psychological, physical, social conditions for the elderly as an individual or a group. The recreation items have to be selected to consider the desire of the elderly, the promotion of a health, a social adaptability and an intrinsic motivation. Second, for the setting up of therapeutic recreation program for the old, recreation leaders have to select the program that the old people can develop an emotional, cognitive, affective, and social abilities. Recreation programs have to provide a field for meeting to old people, and let them hold the diverse human relationship. After program selection, the rules and methods about item selected recreation activity have to be transformed and modulated to suitable to the old age and station in life. Finally, recreation leaders have to use a facilities of old people for therapeutic recreation. The facilities of old people are a public house of the old, old people walfare center, a school of the old, the old college, and a park and hill located surrounding. As the result of therapeutic recreation, the old people can improve their human relationship ability, social adaptability, physial health, and psychological stability.

항암성 생약제로 부터 항암성분의 추출 및 항암활성 측정

이영기(Young Kee Lee),신석우(Suck Woo Shin),염곤(Gon Ryeom) 단국대학교 신소재기술연구소 1993 신소재 연구논집 Vol.3 No.-

지체장애자를 위한 체육프로그램의 운영 방안 연구

이영기(Young Kee Lee) 한국사회체육학회 1995 한국사회체육학회지 Vol.3 No.-

This study aimed to investigate the setting up, deployment, and evaluation about Physical education for the physical handicapped. The canclusive remarks have been made from the result as follows First, for the setting up about physical eduction program, We have to understand Psychological comdition as an individual and a group The selection of an exercise item is to consider growth, development, obstacle Situation, exercise equipment, and support appliances. After selection, the rule and method about the exercise item selected physical activity have to be transformed and modulated to besuitable for the physical handicapped. Second, the deployment of physical education program for the physical handicapped has to be se looted an educational method to he suitable for the physical handicapped. The most important point s to establish The steady guiding philosophy about education of the physical handicapped. Finally, the evaluation process of physical education for the physical handicapped is an effectiveness to program based on validity, reliance, utility and objectivity through comparison on the Pre-post test, observation, ability measurement and physical fitness.

정신지체자를 위한 치료레크리에이션의 지도방안

이영기(Young Kee Lee) 한국여가레크리에이션학회 1999 한국여가레크리에이션학회지 Vol.12 No.-

The primary purpose of this study was to present the teaching plan of recreation for the mentally retarded in order to improve an effect of therapeutic recreation. The conclusive remarks have been made from the result as follows : In order that one may do the setting up about the right purpose and the direction of therapeutic recreation activity, we have to comprehend the mentally retarded in many ways. On the basis of this considerate comprehension, the purpose and the direction have to be planned. The setting up about the plan and contents of therapeutic recreation have to be considered the property, grade, state, desire, and individual difference of the mentally retarded. Therapeutic recreation leaders should make plans to play the role of an efferent duct to give out instinctive emotion through recreation activities to cultivate an adaptable ability in daily life. By doing so, we can accomplish an affirmative transfer effect of recreation activities by the prevention against social deviation phenomena.