흑연 함침법에 의한 흑색 지르코니아의 제조 및 특성분석

이광호,안종필,박주석,이용석,이병하,Lee, Kwang-Ho,Ahn, Jong-Pil,Park, Joo-Seok,Lee, Yong-Seok,Lee, Byung-Ha 한국세라믹학회 2009 한국세라믹학회지 Vol.46 No.4

Zirconia is widely used for structural materials in machinery due to its superior properties, such as high strength, high hardness, and high toughness. Zirconia generally has ivory or white color. Therefore many studies are performed for diversification of zirconia color, in order to be widely uitilized for decoration and machine parts which need distincfive color. In this study, graphite is used to prevent structural defect, to maintain superior properties, and to develop black color of zirconia by impregnation method. As specimen was impregnated at $1600^{\circ}C$ for 2 h, bending strength is 1221 MPa, density is $6.01\;g/cm^3$, hardness is 10.1 GPa, absorption coefficient is 0%, transmittance is Fail, chromaticity is 54. The results indicate that black zirconia has enough properties to be adopted as mechanical parts. Optimum impregnation time is 2 h for various observations.

황동제 주방기구에서 유해중금속의 용출기작에 관한연구

이광호,권기성,전대훈,최병희,김성욱,이선희,이철원,Lee, Kwang-Ho,Kwon, Ki-Sung,Jeon, Dae-Hoon,Choi, Byung-Hee,Kim, Sung-Wook,Lee, Sun-Hee,Lee, Chul-Won 한국포장학회 1999 한국포장학회지 Vol.5 No.2

구이용 불판인 주방용 기구에 사용되는 황동제에서 Pb, Cd, Cu, Zn, Sn등 유해 중금속의 용출과 메카니즘에 대하여 연구하였다. 황동을 대표금속으로 선정하여 용출 온도 (30, 60, 80, $95^{\circ}C$), pH (2.5, 4.3, 6.0, 7.0) 및 시간 (30, 90, 180, 360분)에 따른 금속 용출량 조사에서 온도 및 pH 변화에 따른 시험결과, $95^{\circ}C$, pH 2.5인 조건에서 용출이 가장 많았던 반면, 용출 시간별 시험에서는 180분 이후까지 Pb가 용출된 후 평형 상태를 유지하였다. 납이 용출되는 가시적 현상은 SEM을 통하여 확인할 수 있었다. 황동의 경우, 재질중의 Pb 함량과 용출량과의 관계를 규명하기 위해 Pb 함량별 10종 (0, 0.02, 0.09, 0.1, 0.2, 0.5, 0.9, 1.7, 5.4, 9.2%(w/w))의 시편를 제작하여 4% 초산, $95^{\circ}C$, 30분에서 시험한 결과, 용출규격인 중금속이 1.0 ppm (납으로서) 이하가 되기 위해서는 재질중 허용 Pb 함량은 0.2% 이하가 되어야 했다. The migration mechanism of trace elements, Pb, Cd, Cu, Zn and Sn from brass food-contact utensiles was investigated. The migration of metals from brass was affected by the migration temperature (30, 60, 80 and $95^{\circ}C$), the simulant pH (2.5, 4.3, 6.0 and 7.0) and the migration time (30, 90, 180 and 360 min.). The amount of Pb migration was maximum at $95^{\circ}C$ with pH 2.5. This study indicated that the equilibrium of Pb migration was reached at 180 minutes. The mechanism of Pb migration was investigated with Scanning Electron Microscope (SEM) and Electron Probe Micro Analyzer (EPMA). To correlate the relations between the migration and the content of Pb in brass samples, ten brass samples having known content of Pb (the quantities of Pb in brass ; 0, 0.02, 0.09, 0.1, 0.2, 0.5, 0.9, 1.4, 5.4 and 9.2% (w/w)) were tested in the following conditions, 4% acetic acid, $95^{\circ}C$ and 30 minutes. The result represented that content of Pb in brass samples must be below 0.2% (w/w) to satisfy the 1.0 ppm (as Pb) of Korea Food Code.

일회용 위생장갑에서 Phthalate류 및 Di-(2-ethylhexyl) adipate 분석

이광호,권기성,곽인신,최재천,전대훈,정동윤,최병희,김성욱,이선희,이철원,Lee, Kwang-Ho,Kwon, Ki-Sung,Kwak, In-Shin,Choi, Jae-Chon,Jeon, Dae-Hoon,Jeong, Dong-Youn,Choi, Byung-Hee,Kim, Sung-Wook,Lee, Sun-Hee,Lee, Chul-Won 한국포장학회 2000 한국포장학회지 Vol.6 No.1

일회용 위생장갑에서 diethyl phthalate (DEP), di-n-propyl phthalate (DprP), di-n-butyl phthalate (DBP), di-n-pentyl phthalate (DPP), butylbenzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP) 및 dicyclohexyl phthalate (DCHP) 등과 같은 phthalate ester 와 di-(2-ethylhexyl) adipate (DEHA) 을 분석하였다. 일회용 위생장갑은 소매점에서 구입하였으며, 사염화탄소를 추출용매로 6시간 동안 Soxhlet 장치에서 추출하였다. 8종의 제품 모두 poly-ethylene (PE) 재질이었으며, 식품위생법에 따라 box 포장에 표기 사항이 있었다. 8 종의 모든 제품에서 Phthalate ester 류 와 DEHA는 검출한계를 넘지 않았다. Phthalate esters 인 DEP, DprP, DBP, DPP, BBP, DEHP, DCHP와 DEHA의 검출한계는 각각 1.8, 1.9, 1.3, 1.1, 0.9, 0.7, 2.1 와 0.8 mg/L 이었다. The level of plasticizer such as diethyl phthalate (DEP), di-n-propyl phthalate (DprP), di-n-butyl phthalate (DBP), di-n-pentyl phthalate (DPP), butylbenzyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP), dicyclohexyl phthalate (DCHP) and di-(2-ethylhexyl) adipate (DEHA) was determined in disposable sanitary gloves. Samples of disposable sanitary gloves were taken at retail shops, and their overall extractions in carbon tetrachloride were measured, after establishment of soxhlet appratus in 6 hours. All of 8 samples of disposable sanitary gloves at retail shops were polyethylene (PE). All of the manufactures was voluntarily labelled their boxes of gloves in line Korea Food Code. The level of phthalate esters and DEHA in all of 8 samples were not exceed the detection limit. The detection limits of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 1.8, 1.9, 1.3, 1.1, 0.9, 0.7, 2.1 and 0.8 mg/L, respectively.

스피넬계 흑색 안료를 이용한 흑색 지르코니아 세라믹스의 제조 및 특성분석

이광호,이용석,박주석,이병하,Lee, Kwang-Ho,Lee, Yong-Seok,Park, Joo-Seok,Lee, Byung-Ha 한국세라믹학회 2008 한국세라믹학회지 Vol.45 No.4

The zirconia ceramics are widely used because of their excellent mechanical properties. Recently, many researches to make a colored zirconia was achieved to satisfy the individual aesthetic requirements. In this study, the synthesis of black-color spinel-based inorganic pigments which are stable above $1400^{\circ}C$ and the fabrication of black-colored zirconia using the synthesized pigments are investigated. Inorganic pigments which have spinel structure and near black color were synthesized by a solid state reaction method using a $Fe_2O_3,\;Cr_2O_3$, CoO and NiO powder as a starting materials at $1600^{\circ}C$. Most of synthesized pigments were black colored spinel phases and single spinel phase was successfully synthesized at the composition range of $Cr_2O_3:25{\sim}35%,\;Fe_2O_3:45{\sim}55%$, CoO:20% and NiO:$6{\sim}10%$. The black-colored zirconia was fabricated at $1410^{\circ}C$ with the 5 wt% synthesized pigments and their properties were evaluated. The results showed that the strength value was more than 848 MPa, absorption rate was 0.1%, the brightness of color was $L^*:40{\sim}42$, the tone of color is $a^*:0.2{\sim}0.8$ and $b^*:-1.1{\sim}2.4$. As a result, the black-colored zirconia was suitable for a artificial jewelry or decoration zirconia goods.

대기오염을 고려한 도시의 환경적 수용력 산정 연구

이광호,정연우,Lee, Kwang-Ho,Jeong, Yeun-Woo 한국토지주택공사 토지주택연구원 2011 LHI journal of land, housing, and urban affairs Vol.2 No.4

도시의 무분별한 개발로 인해 수도권의 주요도시는 환경문제를 겪고 있다. 이 중 대기오염은 도시민들이 신체적 경제적 피해를 받고 살아가게 되는 원인으로 작용하고 있다. 이에 인간활동으로 인해 배출되는 대기오염물질을 도시환경이 어느 정도 수용가능한지 예측하고, 이를 통해 적정 도시개발 수준을 검토할 필요성이 제기되고 있다. 본 연구는 대기오염물질 배출량에 따라 대기오염의 양상이 다르게 나타날 것이란 전제 하에, 경기도 과천시를 대상으로 대기환경기준 하에서 허용가능한 대기오염물질 배출량을 산정하고, 이를 기반으로 적정 인구규모를 도출하였다. 분석 결과는 다음과 같다. 첫째, IDW 보간법을 통해 일산화탄소(CO), 이산화질소($NO_2$), 아황산가스($SO_2$) 농도를 추정한 결과 과천시 전체적으로는 대기환경기준을 초과하지 않는 것으로 나타났다. 둘째, 대기오염물질 배출량과 농도와의 상관분석 결과 일산화탄소(CO)와 이산화질소($NO_2$) 농도는 이동오염원과 총오염원, 아황산가스($SO_2$) 농도는 이동오염원과 상관관계가 높은 것으로 나타났다. 셋째, 회귀분석을 통해 대기환경기준 하에서 대기오염물질 배출량을 산정하고 이를 기반으로 지탱가능한 인구수를 산정한 결과, 일산화탄소(CO)의 경우 지탱가능인구수가 실제 인구수보다 높게 나타났고, 이산화질소($NO_2$)와 아황산가스($SO_2$)의 경우는 주거지와 상업시설이 밀집된 도심부와 경계부에서 지탱가능한 인구수를 초과하는 것으로 나타났다. 본 연구를 통해 시도된 환경용량 측정은 대기환경기준 하에서 어느 정도의 인간활동이 적절한 수준인지를 제시해 주었다는데 의의가 있다. 이를 통해 도시환경이 지니는 용량의 범위 내에서 개발행위를 관리함으로써 지속가능한 도시개발이 가능할 것이다. Indiscreet developments cause environmental problems in major cities of Seoul Metropolitan Area. Among the environmental problems, the air pollution leads the citizens' physical and economic damages. Therefore, it needs to predict how much air pollutant which is emitted from human activities can be carried by urban environment, then to examine the reasonable level of urban development This study assumed that the air pollution is represented differently by the amount of emission. With the assumption, the acceptable air pollutant emission which keeps the air quality under the environmental standard is estimated, then the proper population is calculated in the case of Gwacheon, Gyeonggi. The result is as follow: First, air pollution concentrations of CO, $NO_2$, $SO_2$ which are estimated by using IDW interpolation of GIS don't excess the air environmental standard. Second, the result of correlation analysis between air pollutant emission and air pollution concentration shows that CO and $NO_2$ has high correlationship with total source of pollution and linear source of pollution, and $SO_2$ with linear source of pollution. Third, the results of regression analysis show that the acceptable population is bigger that the real population in the case of CO, and with the estimation of $NO_2$ and $SO_2$, the current population in the urban center and boundaries where the residential and commerce land uses are concentrated is bigger than the acceptable population. The consequence of this study is that the estimation of carrying capacity can suggest the acceptable human activities which keep the air quality under the environmental standard. This can leads the sustainable urban development by control the human activities under the carrying capacity of urban environment.

제조업의 허리 강화 : 부품소재중핵기업 육성

이광호,Lee, Gwang-Ho 과학기술정책연구원 2006 혁신정책 Brief Vol.14 No.-

이달의 규격정보(01.12월중)

이광호,Lee, Gwang-Ho 기술표준원 2002 기술표준 Vol.1 No.-

화합물 합성반응 중 Fridel - Crafts Acylation 공정에서의 폭주반응 위험성평가

이광호,김원성,전진우,주영종,박교식,Lee, Kwangho,Kim, Wonsung,Jun, Jinwoo,Joo, Youngjong,Park, Kyoshik 한국안전학회 2021 한국안전학회지 Vol.36 No.3

Heat is generated during the synthesis and mixing process of chemical compounds due to a change in activation energy during the reaction. A runaway reaction occurs when sufficient heat is not removed during the heat control process within a reactor, rapidly increasing the temperature, reaction speed, and rate of heat generation inside the reactor. A risk assessment was executed using an RC-1 (Reaction Calorimeter) during Friedel-Crafts acylation. Friedel-Crafts acylation runs the risk of rapid heat generation during Active Pharmaceutical Ingredient (API) manufacturing; it was used to confirm the risk of a runaway reaction at each synthesis stage and during the mixing process. This study used experimental data to develop a safety efficiency improvement plan to control the risks of runaway and other exothermic reactions, which was implemented at the production site of a chemical plant.

교통사고로 인한 요통환자의 어혈방(瘀血方) 치료효능에 관한 임상적 연구

이광호,문경숙,김태우,박현재,양승인,원승환,권기록,Lee, Kwang-ho,Mun, Kyung-suk,Kim, Tae-woo,Park, Hyun-jae,Yang, Seoung-in,Won, Seung-hwan,Kwon, Ki-rok 대한침구의학회 2004 대한침구의학회지 Vol.21 No.6

Objective : The purpose of this study is to observe the effects of Eo-Hyeol Bang(瘀血方) for the patients with low back pain due to traffic accident. Methods : Eo-Hyeol Bang based on Sa-Am Acupuncture treatment(four needle technic), consists of Taibai(SP3), Taiyuan(LU9), Quchi(LI11). In following research, 60 patients were divided into Group A and Group B of each 30 persons. Only Group A was treated with Eo-Hyeol Bang, Group B was treated with common acupuncture treatment. Results : In VAS, Group A is $5.77{\pm}1.96$ and Group B is $4.53{\pm}2.40$ (P=0.033). In Improvement index, Group A is $0.3191{\pm}0.1597$ and Group B is $0.2267{\pm}0.1297$ (P=0.017). Conclusions : As a result of each P-value, we knew that Eo-Hyeol Bang is more effective than another acupuncture technic.

이광호의 시사칼럼-에이즈 감염자 2천명 돌파

이광호,Lee, Gwang-Ho 한국건강관리협회 2003 건강소식 Vol.27 No.2