LED용 BaGa₂S₄:Eu²⁺ 녹색 형광체의 합성 및 발광특성

김재명,박정규,김경남,이승재,김창해,Kim, Jae-Myung,Park, Joung-Kyu,Kim, Kyung-Nam,Lee, Seung-Jae,Kim, Chang-Hae 한국재료학회 2006 한국재료학회지 Vol.16 No.12

[ $II-III_2-(S,Se)_4$ ] structured of phosphor has been used at various field because those have high luminescent efficiency and broad emission band. Among these phosphors, the europium doped $BaGa_2S_4$ was prepared by solid-state method and had high potential application due to an emissive property of UV region. Also, the common sulfide phosphors were synthesized by using injurious $H_2S\;or\;CS_2$ gas. However, in this study $BaGa_2S_4:Eu^{2+}$ phosphor in addition to excess sulfur was prepared under at 5% $H_2/95%\;N_2$ reduction atmosphere. Thus, this process could be considered as large scale synthesis because of non-harmfulness and simplification. The photoluminescence efficiency of the prepared $BaGa_2S_4:Eu^{2+}$ phosphor increased 20% than that of commercial $SrGa_2S_4:Eu^{2+}$ phosphor. The prepared $BaGa_2S_4:Eu^{2+}$ could be applied to green phosphor for white LED of three wavelengths.

축산식품 중에 잔류하는 Gentamicin 검사를 위한 ELISA 개발에 관한 연구

김재명,이문한,이항,류판동,조명행,박종명,Kim, Jae-Myung,Lee, Mun-Han,Lee, Hang,Ryu, Pan-Dong,Cho, Myung-Haing,Park, Jong-Myung 한국식품위생안전성학회 1994 한국식품위생안전성학회지 Vol.9 No.3

An enzyme-linked immunosorbent assay(ELISA) was developed for the detection of residual gentamicin(GM) in edible animal products. The immunogen(GM-KLH conjugate) and coating antigen(GM-BSA conjugate) were prepared by coupling GM sulfate to keyhole limpet hemocyanin(KLH) and bovine serum albumin(BSA) in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, respectively. Polyclonal antibody to GM was produced in rabbits(New Zealand White, female) by using the immunogen and the antibody titer was measured by indirect ELISA. A competitive ELISA was developed using GM-bovine serum albumin conjugate as a coating antigen, GM(as standards or sample), polyclonal antibody to GM, secondary antibody conjugated with horseradish peroxidase as an enzyme, and H2O2 and o-phenylenediamine dihydrochloride as a substrate and a chromophore, respectively. The detection limit of GM was 10 ng/ml and the standard curve of GM(n=26) was linear up to 10 $\mu\textrm{g}$/ml in this competitive ELISA system. There were no cross-reactivities of the partially purified antibody between GM and the various antibiotice such as amikacin, benzyl-penicillin, chloramphenicol, erythromycin, furazlidone, kanamycin, neomycin, oleandomycin, streptomycin, sulfathiazole and thiamphenicol(CR50<0.05%)

산 에칭에 의한 BaO-B₂O₃-ZnO계 유리조성물의 용출 현상

김재명,홍경준,김남석,김형순,Kim, Jae-Myung,Hong, Kyung-Jun,Kim, Nam-Suk,Kim, Hyung-Sun 한국세라믹학회 2006 한국세라믹학회지 Vol.43 No.1

For producing the fine ribs structure of plasma display panel, the metal ions of barrier materials during the etching process should be understood on the etching mechanism with etching conditions. Etching was done on bulk glasses of the $BaO_B_2O_3-ZnO$ system with $HNO_3$ solution at $40^{\circ}C$. The surface structure of glasses and ion dissolution were analyzed by ICP (Inductive Coupled Plasma measurement). The structure and surface of the etched bulk glass were investigated by using scanning electron microscopy and nanoindenter. As a result, Ba (3-35 ppm/min) and Zn (2-27 ppm/min) ions as major components were leached in the solution and the leached layers were found to be phosphor-rich surface layers. A decrease of the bridge oxygen and relative increase of non bridge oxygen in the etched glass were found by X-ray photoelectron spectroscopy.

고상법을 이용한 LED용 SrGa₂S₄:Eu 녹색 형광체의 합성 및 발광특성

김재명,김경남,박정규,김창해,장호겸,Kim, Jae-Myung,Kim, Kyung-Nam,Park, Joung-Kyu,Kim, Chang-Hae,Jang, Ho-Gyeom 대한화학회 2004 대한화학회지 Vol.48 No.4

The $SrGa_2S_4:Eu^{2+}$ green emitting phosphor has been studied as a luminous device for CRT (Cathode Ray Tube) or FED (Field Emission Display) and EL (Electroluminescence). This phosphor, also, is under noticed for LED (Lighting Emitting Diode) phosphor, which makes use of excitation characteristics of long wavelength region. The $SrGa_2S_4:Eu^{2+}$ phosphor was prepared generally conventional synthesis method using flux. However, this method needs high heat-treated temperature, long reaction time, complex process and harmful $H_2S$or $CS_2$ gas. In this works, therefore, we have synthesized $SrGa_2S_4:Eu^{2+}$ using SrS, $Ga_2S_3$, and EuS as starting materials, and the mixture gas of 5% H2/95% N2 was used to avoid the $H_2S$or $CS_2$. We investigated the luminescence characteristic of $SrGa_2S_4:Eu^{2+}$ phosphor prepared in various synthesis conditions, performed post-treatment and sieving process for application to LED. 기존의 $SrGa_2S_4:Eu^{2+}$ 녹색 발광 형광체는 주로 CRT (Cathode Ray Tube)용이나 FED (Field Emission Display), 그리고 EL (Electroluminescence)용 발광소자로 많이 연구되어졌다. 현재는 장파장 영역의 여기 특성을 이용한 LED (Light Emitting Diode)용 형광체로 주목 되어지고 있다. $SrGa_2S_4:Eu^{2+}$ 형광체의 일반적 합성 방법은 Flux를 이용하여 인체에 유해한 $H_2S$나 $CS_2$ 기체를 사용할 뿐만 아니라 높은 합성온도, 긴 반응시간 및 공정이 복잡한 단점을 지니고 있다. 따라서 본 실험은 황화물계 원료인 SrS, $Ga_2S_3$ 그리고 EuS를 출발 물질로 하여 $H_2S$ 기체를 사용하지 않고 혼합 기체$(5% H_2/95% N_2)$를 사용해 환원 분위기 하에서 $SrGa_2S_4:Eu^{2+}$을 합성하였다. 그리고 다양한 합성 조건과 LED용으로 사용되기 위해 수세처리와 Sieving 과정을 거친 형광체의 발광특성을 검토하였다.

죽음 준비를 위한 세 의사들의 대담

김재명,Kim, Jae-Myung 연세대학교 의과대학 2015 의학교육논단 Vol.17 No.2

유기물로 수식된 몬트모릴로나이트 제조 및 특성조사

김재명,유중환,최의석,이성민,김형태,Kim, Jae-Myung,Yoo, Jung-Whan,Choi, Eui-Seok,Lee, Sung-Min,Kim, Hyung-Tae 한국세라믹학회 2004 한국세라믹학회지 Vol.41 No.1

층상구조를 갖는 점토광물은 층상의 이온교환자리에 친소수성 유기물을 화학적으로 치환할 수 있어 도자기 소지의 친소수성 정도를 조절할 수 있다. 본 연구에서는 Montmorillonite를 이온교환법으로 dodecylamine, hexadecylamine과 반응시켜 유기물이 점토광물에 복합화된 유기-점토 복합체를 조조하였다. 유기물이 점토광물 구조에 치환된 위치 및 층상구조의 간격변화는 FT-IR과 WAXD로, 수식된 유기물의 양은 TG-DSC, C/S 기기를 사용하여 조사하였다. 분석을 통하여 유기물은 층상에 선택적으로 치환하여 층간격을 증가 (12${\AA}{\leftrightarro}16{\AA}$) 시키는 역할을 하였고, 비교적 친수성을 보이는 MMT가 첨가된 가소제로 인하여 소수성으로 변하고 있음을 발견하였다. Hydrophilicity and hydrophobicity of pottery bodies can be controlled via chemical substitution of layered clay with hydrophilic and hydrophobic organics. In this study, organo-clay nanocomposites were prepared by ion-exchange of montmorillonite with dodecylamine and hexadecylamine, respectively. Substitution sites of organics and the interval changes of layered materials are characterized by FT-IR and WAXD and organics amounts loaded and water comtents contained by C/S analysis and TG-DSC. The organics were selectively intercalated so that increase layer interval from 12${\AA}\; to\;16{\AA}$. Organo-modified clay is changed to more hydrophobic comparing to clay itself.

철광석의 역학적 특성 평가에 관한 연구

김재명,김찬욱,석한길,Kim, Jae Myung,Kim, Chan Wook,Suk, Han Gil 한국자원리싸이클링학회 2014 資源 리싸이클링 Vol.23 No.4

본 연구에서는 자원고갈에 따른 철광석의 자원화 가능성에 대한 연구를 수행하였다. 이를 위하여 Fe함량이 각각 64%(A광석)와 57%(B광석)인 Fe품위를 갖는 2종의 철광석 시료를 대상으로, 광석의 파쇄거동 특성 및 조직학적 측면에서 비교분석을 통하여 광종별 품위향상 가능성을 알아보고자 하였다. SEM 분석결과, 철광석 A의 경우 철산화물과 맥석이 분리된 형태로 분포되어 있으며, B광석의 경우는 철산화물과 맥석이 혼재되어 분포되어 있었다. 이는 B광석에 비해 A광석이 분쇄에 의한 단체분리가 보다 용이함을 의미한다. 따라서 A광석은 적절한 입도로 분쇄 후 자력선별 등에 의한 품위 향상이 가능할 것으로 판단된다. 반면 B광석은 단체분리를 위하여 A광석보다 미립으로 분쇄하여야 할 것으로 판단되나, 열처리 전 62 ~ 68% Fe조성이 열처리 후 약 81%로 증가하는 경향을 보여, 열처리를 적용한 품위 향상이 가능할 것으로 사료된다. The objective of this study is to investigate the possibility of beneficiation of low grade iron ore. Iron ore A might be upgraded by the mineral liberation effect, while iron ore B was expected to be difficult to upgrade. However, the Fe contents of iron ore B were increased from 68% to 81% by the heat treatment process. Iron ore A was found to possibly enrich the Fe components through the physical separation process, such as magnetic separation, floatation and gravity concentration. In the case of iron ore B, it was possible to concentrate the Fe components through the heat treatment process.

다량 Cl성분이 함유된 플라이 애쉬로부터 유리화 및 결정화 현상

김재명,김형순,Kim, Jae-Myung,Kim, Hyung-Sun 한국재료학회 2002 한국재료학회지 Vol.12 No.12

To recycle waste materials, this work was focused on development of glass-ceramic from incinerator fly ash with a large content of Cl and its physical property was evaluated. In the process, water washing as a pre-treatment before melting the fly ash was used to remove large amount of Cl component in the ash and to reduce melting temperature. As a result, glass was obtained at below $100^{\circ}C$ compared to the melting temperature before washing the ash. Also, internal crystallization occurred under single stage heat treatment (at $850-950^{\circ}C$ for 20-340min) without adding other materials into the ash. It was shown that the glass-ceramic was composed of four crystals, diopside, anorthite, akermanite, and unknown phase. Hardness of 8.3GPa was found in the glass-ceramic, which is a high value compared to reported others. Thus, the present process suggests that a good glass-ceramic produced from an incinerator ash could be applicable for structural materials in terms of economic and environmental points.

의과대학생 죽음교육을 위한 국내 저역서 현황 및 유형과 활용방안

김재명,Kim, Jae-Myung 연세대학교 의과대학 2020 의학교육논단 Vol.22 No.3

ANALYSIS OF RATE STABILITY IN THE KOREAN LINER SHIPPING INDUSTRY

김재명 ( Jae Myung Kim ) 충북대학교 산업경영연구소 1991 産業과 經營 Vol.4 No.2