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.

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.

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.

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.

올해엔 '나눔'을 생활화하자

이광호,Lee, Gwang-Ho 한국건강관리협회 2005 건강소식 Vol.29 No.1

선로조류를 이용한 전력계통 동태 안전성 평가 연구

이광호,Lee, Kwang-Ho 대한전기학회 1999 전기학회논문지A Vol.48 No.2

This paper presents an application of artificial neural networks(ANN) to assess the dynamic security of power systems. The basic role of ANN is to provide assessment of the system's stability based on training samples from off-line analysi. The critical clearing time(CCT) is an attribute which provides significant information about the quality of the post-fault system behaviour. The function of ANN is a mapping of the pre-fault, fault-on, and post-fault system conditions into the CCT's. In previous work, a feed forward neural network is used to learn this mapping by using the generation outputs during the fault as the input data. However, it takes significant calculation time to make the input data through the network reduction at a fault as the input data. However, it takes significant calculation time to make the input data through the network reduction at a fault considered. In order to enhance the speed of security assessment, the bus data and line powers are used as the input data of the ANN in thil paper. Test results show that the proposed neural networks have the reasonable accuracy and can be used in on-line security assenssment efficiently.

이광호의 시사칼럼-원정출산 한해 5천명

이광호,Lee, Gwang-Ho 한국건강관리협회 2003 건강소식 Vol.27 No.5

요골신경마비(撓骨神經痲痺) 치험(治驗) 1례(例)

이광호,김태우,장보형,권오섭,류충렬,조명래,문경숙,Lee, Kwang-Ho,Kim, Tae-Woo,Jang, Bo-Hyoung,Kweon, O-Seop,Ryu, Chung-Ryeul,Cho, Myung-Rae,Mun, Kyung-Suk 대한약침학회 2004 Journal of pharmacopuncture Vol.7 No.3

Objective : The purpose of this study is to report the patient with radial nerve palsy, who improved by oriental medical treatment. Methods : The patient was managed by Cathami Flos aqua-acupuncture, Dong-Qi acupuncture treatment, Comman acupuncture treatment and Herbal medicine. We took pictures of patient's wrist and checked the power of muscles. And we checked the numbness of thumb that was patient's subjective sensation. Results : After 2 weeks-treatment, the movement and power of wrist was restored to nearly normal range, also the numbness of thumb was removed. Combined oriental medical treatment can treat radial nerve palsy earlier than the other methods. Conclusions : The results suggest that combination of Cathami Flos aqua-acupuncture, Dong-Qi acupuncture treatment, Comman acupuncture treatment and Herbal medicine is good method for treatments of radial nerve palsy. But further studies are required to concretely prove the effectiveness of this method for treating radial nerve palsy.

이광호의 시사칼럼-고령화 사회 대책 시급

이광호,Lee, Gwang-Ho 한국건강관리협회 2003 건강소식 Vol.27 No.11

3차원 불규칙 수치파동수조(3D-NIT) 모델의 적용성에 관한 연구

이광호,백동진,김도삼,Lee, Kwang-Ho,Baek, Dong-Jin,Kim, Do-Sam 해양환경안전학회 2012 해양환경안전학회지 Vol.18 No.5

In this study, 3D-NIT(3-Dimensional Numerical Irregular wave Tank) model in which regular wave as well as stable irregular wave can be generated in 3-dimensional numerical irregular wave tank was proposed. To verify validity, the following steps need to be conducted: 1) comparative analysis between calculated waveforms and targeted waveforms at the wave generating point, 2) comparative analysis with the existing experimental values of overtopping volume estimated, targeting shore protection structures installed on a slope bed, 3) comparison with the existing numerical and hydraulic experimental results through application in the analysis on the wave deformation by structures and wave force acting on the vertical cylindrical structures. Based on the results, characteristics of the breaking wave forces according to incident waves and interval distance of structures were identified through application of 3D-NIT model in the analysis on the breaking wave forces acting on the cylindrical structures installed on a slope bed, and reflection and overtopping was reviewed through application in the special breakwaters on the domestic fields. The numerical results obtained the 3D-NIT model are in good agreement with experimental results, and its applicaion to the complex-shpaed coastal structures is verified. 본 연구에서는 3차원수치파동수조에 규칙파뿐만 아니라 안정적인 불규칙파가 조파될 수 있는 새로운 조파시스템 3D-NIT(3-Dimensional Numerical Irregular wave Tank)모델을 제안한다. 그의 타당성을 검증하기 위하여 1) 조파지점에서 계산파형과 목표파형을 비교 검토하고, 2) 경사수심역에 설치된 호안구조물을 대상으로 산정된 기존 월파량에 대한 실험치와 비교 검토하며, 3) 연직원주 구조물에 작용하는 파력 및 구조물에 의한 파랑변형의 해석에 적용하여 기존의 수치 및 수리실험결과와 비교한다. 이상의 결과를 기초로 3D-NIT모델을 경사수심역에 설치된 원주구조물에 작용하는 쇄파력의 해석에 적용하여 입사파고, 구조물의 이격거리 등에 따른 작용쇄파력의 특성을 규명하고, 더불어 국내현장의 특수방파제에 적용하여 반사율, 월파량 등을 검토하였다. 그 결과 본 연구에서 제안하는 3D-NIT모델을 이용한 수치실험결과는 기존의 수리모형실험을 잘 재현하고 있음을 확인하였고 복잡한 형상을 갖는 해안구조물의 해석에 적용할 수 있음이 확인되었다.