• The Korea Journal of Herbology
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• v.22 no.3
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• pp.39-45
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• 2007

Objectives : The purpose of this study is to investigate the delayed luminescence-biophoton emission from root of Angelica sinensis D., Angelica acutiloba K., and Angelica pubescens M. These three species of Genus Angelica are now imported from other nations into Republic of Korea. Methods : Randomly selected samples from roots of Angelica sinensis D., Angelica acutiloba K., and Angelica pubescens M. were radiated with 150 W metal halide lamp for 1 minute. After radiation. biophoton emissions of each sample were detected by electron multiplication(EM)-charge coupled device camera. The detected biophoton image was calculated with unit of counts per pixel. Results: The average biophoton emissions of delayed luminescence with EM ratio of $\times$150 and $\times$250 were distinguished significantly. The maximum biophoton emissions of delayed luminescence with EM ratio of $\times$250 were distinguished significantly. Conclusions : These results suggest that biophoton imaging of roots of Angelica sinensis D., Angelica acutiloba K., and Angelica pubescens M. could become the meaningful method for the study of differentiation for these three species of Genus Angelica.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.4
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• pp.9-16
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• 2005

In this paper, electronic ballast using double resonant inverter for 250[W] MHD lamp is designed and implemental Electronic ballast reduce a turn-onion loss by using ZVS(Zero Voltage Switching) technic in the double resonant inverter, and when circuit have an analysis, the characteristic evaluations is described generally by using the normalized i:ぉ used numerical analysis. We conform a rightfulness of theoretical analysis by experimental waveforms, rouble resonant inverter for 250[W]) MHD lamp is operated safely.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.177-177
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• 1996

Taurine Chloramine (Tau-Cl) inhibits production of nitric oxide(NO) and tumor necrosis factor-alpha (TNF-${\alpha}$) in activated peritoneal macrophages, similar In that previously reported for activated RAW 264.7 cells. In addition, the effect of Tau-Cl and taurine on superoxide anion (O$\_$2/$\^$-/) Production in murine peritoneal exudate polymorphonuclear leukocytes (PMN) was examined. Tau-Cl inhibited O$\_$2/$\^$-/ production in a manner that was dose-dependent and reversible, Taurine also inhibited O$\_$2/$\^$-/ production by stimulated PMN, but at higher concentrations and to a lesser extent than Tau-Cl. The effects of taurine on O$\_$2/$\^$-/ production was attributed to the in vitro formation of Tau-Cl catalyzed by PMN associated halide-dependent myeloperoxidase. In contrast, production of NO and TNF-${\alpha}$ by activated peritoneal exudate macrophages was inhibited by Tau-Cl while taurine was without effect. These data lend support to the notion that Tau-Cl may participate ill the inflammatory responses by modulating production of inflammatory mediators.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.85-88
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• 2009

In this paper, We has been studied the lifetime degradation of LED lighting system compared to MH lighting. Especially the effect of temperature level on the lifetime degradation has been investigated. The results show that temperature plays a role in the lifetime degradation and slope of degradation line represent as temperature level differently. However, It is possible to estimate the lifetime of LED lighting system using equation induced the slope of degradation line.

• Journal of radiological science and technology
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• v.6 no.1
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• pp.43-67
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• 1983

In order to increase the sensitivity of the photographic emulsion, one of the chemical sensitizers hydroxymethane sulfonic acid sodium salt(HMS) was applied through the chemical ripening process and following four types of emulsion were prepared. Their grain sizes were determined through the electron microscope. The ranges of average grain sizes were $0.05-0.40{\mu}m$ for silver chlorobromide emulsion of low sensitivity $0.10-0.45{\mu}m$ for the silver chlorobromide emulsion of medium sensitivity, $0.60-1.05{\mu}m$ for the silver iodobromide emulsion of high sensitivity, and $0.90-1.55{\mu}m$ for the ammonical silver iodobromide emulsion of high sensitivity. Through the reduction sensitization with HMS, they showed significant sensitivity enhancement by the increment of HMS concentration above pH 5.5 and pBr 3.0. Required sensitivity was obtained above pH 6.2 and pBr 3.3 when sulfur and gold sensitization were applied. Fog formed along the reduction sensitization was successfully prevented by the addition of 5.5-dimethylhydantion.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1625_1626
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• 2009

최근 세라믹 메탈할라이드 램프의 사용이 증가함에 따라 고연색성, 장수명에 대한 기대치가 높아지고 있다. 이런 추세에 의하여 현재 정격수명이 15,000 ~ 20,000시간의 세라믹 메탈할라이드 램프가 개발되고 있으며 신뢰성에 대한 문제 또한 부각되고 있는 실정이다. 본 논문에서는 이러한 세라믹 메탈할라이드 램프의 수명 특성을 알아보기 위하여 "신뢰성기준 RS C 0085"를 바탕으로 램프를 20분 점등후 20분 소등을 한 주기로 하여 1,200회를 반복한 후 광학적 특성 및 전기적 특성을 측정하여 실험 전 초기 특성과 비교 분석하였다. 광학적 특성으로 광속과 효율은 3.1 [%] 감소, 연색성은 2.3 [%] 감소, 색온도 변화를 가져왔다. 전기적 특성으로는 램프 열화로 인한 내부저항의 변화로 인해 전압이 1.4 [V] 증가, 전류가 0.02 [A] 감소하였다.

• Journal of Adhesion and Interface
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• v.21 no.2
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• pp.41-50
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• 2020

Organic-inorganic metal halide perovskite has shown a great promise in photovoltaic applications because of the skyrocketing power-conversion efficiencies up to 25.2% and their potentially low production cost. However, it also has critical issue of substantial material degradation during device operation to be overcome for successful commercialization. Understanding the nature of defects and their photochemistry related to material degradation is needed. Furthermore, strategy to passivate defects in perovskite should be adopted to improve the stability of perovskite. In this article, we present predominant defects formation in perovskite that contribute to material degradations in perovskite solar cells. We then discuss how material stability can be improved through reliable defect passivation engineering.

• The Korea Journal of Herbology
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• v.21 no.2
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• pp.175-180
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• 2006

Objectives : The difference of delayed luminescence-biophoton emission was investigated in Cervi Pantotrichum Cornu selected randomly. Cervi Pantotrichum Cornu was used as a tonic in Korean medicine. Methods : Randomly selected samples of Cervi Pantotrichum Cornu were radiated with 150 W metal halide lamp for 1 minute. After radiation, biophoton emissions of each sample were detected by electron multiplication(EM)-charge coupled device camera. The detected biophoton image was calculated with unit of counts per pixel. Results : The average biophoton emissions of delayed luminescence with EM ratio of ${\times}l50\;and\;{\times}250$ were distinguished significantly. The maximum biophoton emissions of delayed luminescence with EM ratio of ${\times}250$ were distinguished significantly. Conclusion : These results suggest that biophoton imaging of Cervi Pantotrichum Cornu could become the meaningful method for the study of differentiation and classification of Cervi Pantotrichum Cornu.

• Journal of the Korean Chemical Society
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• v.27 no.1
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• pp.46-52
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• 1983

Selective reduction of halide (Br, I) with lithium borohydride in halogen compounds containing chloro, nitro, ester and nitrile groups was achieved satisfactorily. 1-Bromo-4-chlorobutane was reduced to 1-chlorobutane in 96% yield and the reduction of p-nitrobenzyl bromide gave p-nitrotoluene in 98% yield. However, the selectivity on the reduction of ethyl 3-iodopropionate and 4-bromobutyronitrile required the presence of equimolar pyridine to give good yield of ethyl propionate (93%) and n-butyronitrile (88%), respectively. In competitive reduction of 1-bromoheptane and 2-bromoheptane, lithium borohydride reduced 1-bromoheptane preferentially in the molar ratio of 93:7.

• Journal of the Korean Chemical Society
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• v.9 no.1
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• pp.23-28
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• 1965

Halogen exchanges between benzyl chloride and chloride ion have been studied in 90% ethanol-water mixture, and activation parameters in the exchange reaction have been determined; ${\Delta}H^{\neq}$ = 18. 50 Kcal and ${\Delta}S^{\neq}$ = -22. 09 e. u. Results indicated that the reaction proceeded via a typical bimolecular mechanism. The importance of nucleophilic ability of attacking anion in $S_N2$ process has been stressed giving some experimental evidence. The order of reactivity of halides in the exchange reaction is better explained with the Swain's nucleophilic parameter than with the bond dissociation energies.