• Title/Summary/Keyword: Heat absorption

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Purification and Characterization of Carotenoprotein from the Muscle of Ascidian, Halocynthia roretzi (우렁쉥이 육으로부터 Carotenoprotein의 분리.정제 및 특성)

  • Kang, Ok-Ju;Byun, Hee-Guk;Jeon, You-Jin;Kim, Jong-Bae;Kim, Se-Kwon
    • Applied Biological Chemistry
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    • v.41 no.1
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    • pp.31-41
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    • 1998
  • A carotenoprotein from the muscle of Ascidian (Halocynthia roretzi) was purified by ion exchange chromatography and gel filtration chromatography, and analyzed molecular weight, stability of pH and heat, effect of denaturing agents, amino acids and fatty acids composition. The purified carotenoprotein had absorption maxima of 463 nm and 439 nm. The carotenoprotein had an approxmimate molecular weight of 64.4 kDa in polyacrylamide gel electrophoresis. The amino acid compositions of carotenoprotein were mainly Gly (15.39%), Asn (11.31%), Gln (10.62%) and Ser (13.35%). The major fatty acids composition of carotenoprotein were $C_{16:1(n-7)}\;(15.4%)$, $C_{22:1(n-9)}\;(14.5%)$ and $C_{20:1(n-11)}\;(11.4%)$. The monounsaturated fatty acids (45.2%) contained abundant content compared to other saturated (38.1%) and polyunsaturated (11.7%) fatty acids.

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Cases of Green Tobacco Sickness: Occupational Nicotine Poisoning in Tobacco Harvesters in Korea (담배 재배 농부에서 발생한 담배잎농부병(green tobacco sickness) 증례)

  • Lim, Hyun-Sul;Lee, Kwan
    • Journal of agricultural medicine and community health
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    • v.26 no.2
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    • pp.7-14
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    • 2001
  • Cases of green tobacco sickness were described. During the cutting of tobacco plants throughout harvest, four cases of green tobacco sickness occurred in August 2001, Korea. The range of age was 42-55 years. The most frequent symptoms included dizziness, weakness, nausea, vomiting, abdominal cramps, headache, and difficulty breathing. All affected individuals worked in fields of wet tobacco, where their clothes became wet from moisture on the plants or sweating. They were all healthy, except one with hypertension. They are all non-smokers. They recovered after fluid and antiemetic administrations within two days. Most of doctors misdiagnosed their symptoms as a pesticide poisoning or heat injury. Green tobacco sickness is a condition that has long been known as an occupational health risk among tobacco harvesters. Nicotine poisoning by dermal absorption is reported to be the cause of green tobacco sickness. In Korea, there are many tobacco harvesters, and most of them may be sticken with green tobacco sickness. But, no case of green tobacco sickness has been reported. We report cases of green tobacco sickness occurred to the tobacco harvesters with a review of articles.

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An Improvement in the Properties of MH Electrode of Ni/MH Battery by the Copper Coating (Ni/MH 전지에서 Cu 도금에 의한 음극활물질의 전극 특성 향상)

  • Cho, Jin Hun;Kim, In Jung;Lee, Yun Sung;Nahm, Kee Suk;Kim, Ki Ju;Lee, Hong Ki
    • Applied Chemistry for Engineering
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    • v.8 no.4
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    • pp.568-574
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    • 1997
  • The effect of microencapsulation of maetal hydride (MH) with copper on the electrode performance of a Ni/MH battery has been investigated. The MH electrodes were prepared with a combination of cold press and paste methods. The discharge capacity of the electrode increased with an addition of small amounts if CMC into the electrode, but decreased when heat-treated in an oxygen-free nitrogen flow. The capacity of a Cu-coated $LaNi_5$ electrode was higher than that of LaNi5electrode. The discharge capacity of the electrode prepared with Cu-coated $LaNi_5$ increased with the increase of copper content in the electrode. It is considered that the increase of copper content enhanced the current density on the electrode surface, leading to the increase of the discharge capacity The MH electrode coated by an acidic electroless plating method showed much higher discharge capacity than that using an alkaline electroless plating method. The discharge capacity of the $LaNi_{4.5}Al_{0.5}$ electrode was higher than that of the $LaNi_5$ electrode. Also, the effect of microencapsulation on the deactivation of $LaNi_5$ was studied using an absorption-desorption cycle in CO-containing hydrogen.

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Effects of Cadmium on the Gene Expression Profile in the Rat Basal Ganglia (카드뮴이 흰쥐 뇌기저핵의 유전자 발현에 미치는 영향)

  • Lee, Chae-Kwan
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.20 no.1
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    • pp.29-40
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    • 2010
  • This study was aimed at investigating the gene expression profile in basal ganglia of cadmium exposed rat based on cDNA array analysis. For cDNA array analysis, adult Sprague-Dawley male rats (350 ${\pm}$ 25 g) were intraperitoneally injected with 2.0 mg/kg body weight/day of CdCl2 (0.3 ml) for 5 days. For doserelated gene expression analysis rats were intraperitoneally injected with 0.0, 0.1, 0.3, 1.0 mg/kg body weight/day of CdCl$_2$ for 5 days. Control rats were injected with equal volume of saline. Cadmium concentration of brain was analyzed by atomic absorption spectrophotometer. For cDNA array, RNA samples were extracted from basal ganglia and reverse-transcribed in the presence of [${\alpha}$32P]-dATP. Membrane sets of the Atlas Rat 1.2 array II and Toxicology array 1.2 (Clontech, Palo Alto, CA) were hybridized with cDNA probe sets. RT-PCR was employed to validate the relative gene expression patterns obtained from the cDNA array. Northern blot hybridization methods were employed to assess the dose-related gene expression. Among the 2352 cDNAs, 671 genes were detected in both array sets and 63 genes of 38 classes showed significant (more than two fold) changes in expression. Thirty five of these genes were up-regulated and twenty eight were down-regulated in the cadmium exposed group. According to the dose-related gene expression analysis, heat shock 27 kDa protein (HSP27), neurodegeneration-associated protein 1 (Neurodap 1) genes were significantly up-regulated and melatonin receptor 1a (Mel1a), Kinesin family member 3C (KIF3C), novel kinesinrelated protein (KIF1D) genes were significantly downregulated even in the low-dose of cadmium exposed group (0.1 mg/kg body weight/day). Conclusions Sixty three genes detected in this study can give some more useful informations about the cadmium-induced neurotoxicity in the basal ganglia. As well as, HSP27, Neurodap1, Mel1a, KIF3C and KIF1D genes may be useful for the study of the cadmium-induced neurotoxicity because these genes showed dramatic changes of mRNA levels in response to the low dose of cadmium exposure.

Growth and effect of thermal annealing for $AgGaSe_2$ single crystal thin film by hot wall epitaxy (Hot wall epitaxy(HWE)법에 의한 $AgGaSe_2$ 단결정 박막 성장과 열처리 효과)

  • Baek, Seung-Nam;Hong, Kwang-Joon;Kim, Jang-Bok
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.16 no.5
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    • pp.189-197
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    • 2006
  • A stoichiometric mixture of evaporating materials for $AgGaSe_2$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $AgGaSe_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy(HWE) system. The source and substrate temperatures were $630^{\circ}C\;and\;420^{\circ}C$, respectively. The temperature dependence of the energy band gap of the $AgGaSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=1.9501eV-(8.79x10^{-4}eV/K)T^2(T+250K)$. After the as-grown $AgGaSe_2$ single crystal thin films was annealed in Ag-, Se-, and Ga-atmospheres, the origin of point defects of $AgGaSe_2$ single crystal thin films has been investigated by the photoluminescence (PL) at 10K. The native defects of $V_{Ag},\;V_{Se},\;Ag_{int},\;and\;Se_{int}$ obtained by PL measurements were classified as a donors or accepters type. And we concluded that the heat-treatment in the Ag-atmosphere converted $AgGaSe_2$ single crystal thin films to an optical p-type. Also, we confirmed that Ga in $AgGaSe_2$/GaAs did not form the native defects because Ga in $AgGaSe_2$ single crystal thin films existed in the form of stable bonds.

Effect of Thermal Annealing for MgGa2Se4 Single Crystal Thin Film Grown by Hot Wall Epitaxy (뜨거운 곁쌓기 법에 의해 성장된 MgGa2Se4 단결정 박막의 열처리 효과)

  • Bang, Jinju;Kim, Hyejeong;Park, Hwangseuk;Kang, Jongwuk;Hong, Kwangjoon
    • Journal of Sensor Science and Technology
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    • v.23 no.1
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    • pp.51-57
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    • 2014
  • The evaporating materials for $MgGa_2Se_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $MgGa_2Se_4$ compounded polycrystal powder was deposited on thoroughly etched semi-insulated GaAs(100) substrate by the hot wall epitaxy (HWE) method system. The source and substrate temperatures of optimized growth conditions, were $610^{\circ}C$ and $400^{\circ}C$, respectively.The source and substrate temperatures were $610^{\circ}C$ and $400^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by double crystal X-ray diffraction (DCXD). The temperature dependence of the energy band gap of the $MgGa_2Se_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=2.34\;eV-(8.81{\times}10^{-4}\;eV/K)T^2/(T+251\;K)$. After the as-grown $MgGa_2Se_4$ single crystal thin films was annealed in Mg-, Se-, and Ga-atmospheres, the origin of point defects of $MgGa_2Se_4$ single crystal thin films has been investigated by the photoluminescence (PL) at 10 K. The native defects of $V_{Mg}$, $V_{Se}$ obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Se-atmosphere converted $MgGa_2Se_4$ single crystal thin films to an optical n-type. Also, we confirmed that Ga in $MgGa_2Se_4$/GaAs did not form the native defects because Ga in $MgGa_2Se_4$ single crystal thin films existed in the form of stable bonds.

Study on Point Defect for $AgGaS_2$ Single Crystal Thin film Obtained by Photoluminescience Measurement Method (광발광 측정법에 의한 $AgGaS_2$ 단결정 박막의 점결함 연구)

  • Hong, Kwang-Joon;Kim, Koung-Suk
    • Journal of the Korean Society for Nondestructive Testing
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    • v.25 no.2
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    • pp.117-126
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    • 2005
  • A stoichiometric mixture of evaporating materials for $AgGaS_2$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $AgGaS_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $590^{\circ}C\;and\;440^{\circ}C$, respectively The temperature dependence of the energy band gap of the $AgGaS_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=2.7284 eV-(8.695{\times}10^{-4}eV/K)T^2/T(T+332K)$. After the as-grown $AgGaS_2$, single crystal thin films was annealed in Ag-, S-, and Ga-atmospheres, the origin of point defects of $AgGaS_2$ single crystal thin films has been investigated by the photoluminescence(PL) at 10K. The native defects of $V_{Ag},\;V_s,\;Ag_{int},\;and\;S_{int}$, obtained by PL measurements were classified as a donors or acceptors type. And we concluded that the heat-treatment in the Ag-atmosphere converted $AgGaS_2$ single crystal thin films to an optical n-type. Also, we confirmed that Ga in $AgGaS_2$ crystal thin films did not form the native defects because Ga in $AgGaS_2$ single crystal thin films existed in the form of stable bonds.

Properties of Concrete Panel Made by Light Weight Aggregates (인공경량골재로 제조된 콘크리트 패널의 물성)

  • 엄태호;김유택
    • Journal of the Korean Ceramic Society
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    • v.41 no.3
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    • pp.221-228
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    • 2004
  • Basic properties of artificial lightweight aggregate by using waste dusts and strength properties of LWA concrete were studied. Bulk specific gravity and water absorption of artificial lightweight aggregates varied from 1.4 to 1.7 and 13 to 16%, respectively. Crushing ratio of artificial lightweight aggregate was above 10% higher than that of crushed stone or gravel. As a result of TCLP leaching test, the leaching amount of tested heavy metal element was below the leaching standard of hazardous material. Slump, compressive strength and stress-strain properties of LWA concrete made of artificial lightweight aggregate were tested. Concrete samples derived from LWA substitution ratio of 30 vol% and W/C ratio of 45 wt% showed the best properties overall. Thermal insulation and sound insulation characteristics of light weight concrete panel with the optimum concrete proportion were tested. Average overall heat transmission of 3.293W/㎡$^{\circ}C$ was observed. It was higher by about 15% than those of normal concrete made by crushed stone. Sound transmission loss of 50.9 ㏈ in frequency of 500 ㎐ was observed. It was higher by about 13% than standard transmission loss.

Effect of Long Period Usage of Polyolefin Film on Growth and Fruit Quality in Korea Melon(Cucumis melo L. var makuwa Makino) (폴리올레핀계 필름 장기사용이 참외의 생육 및 품질에 미치는 영향)

  • Shin, Yong-Seub;Yeon, Il-Kweon;Lee, Ji-Eun;Cheong, Jong-Do;Choi, Seong-Yong;Chung, Doo-Seok
    • Journal of Bio-Environment Control
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    • v.18 no.1
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    • pp.9-14
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    • 2009
  • This experiment was conducted to investigate the difference among 3-years-used Polyolefin films which were J-1, J-2 and J-3 having differences in film thickness, infrared absorption and ultraviolet penetration from Jan. 16,2006. And 1-year-used Polyethylene film K-1 used from Jan. 16,2008, for covering film of greenhouse for korea melon cultivation. J-2, J-3 and J-1 films were better for keeping heat in order, and J-2 film was the best in plant growth at early stage. The first blooming and harvesting days in J-2 film were earlier 10 days than those in K-1 film. Chromaticity and soluble solid of harvested fruit in J-3, J-1 and J-2 films were higher than those in K-1 film. Marketable yields in J-2, J-1 and J-3 films were higher in order.

Effect of Long Time Usage of Soft Film on the Growth and Yield in Oriental Melon (Cucumis melo L. var makuwa Makino) (연질필름의 장기사용이 참외의 생육 및 수량에 미치는 영향)

  • Shin, Yong-Seub;Yeon, Il-Kweon;Lee, Ji-Eun;Do, Han-Woo;Cheung, Jong-Do;Park, Jong-Wook;Choi, Seong-Yong;Chung, Doo-Seok
    • Journal of Bio-Environment Control
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    • v.19 no.3
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    • pp.135-139
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    • 2010
  • This experiment was conducted to investigate the difference among 3-years-used polyolefin films which were J-l, J-2 and J-2 having differences in film thickness, infrared absorption and ultraviolet penetration from Jan. 16, 2006. And 1-year-used polyethylene film K-1 used from Jan. 16, 2009, for covering film of greenhouse for oriental melon cultivation. J-2, J-3 and J-1 films were better for keeping heat in order, and J-2 film was the best in plant growth at early stage. The first blooming and harvesting days in J-2 film were earlier 15 days than those in K-1 film. Chromaticity and soluble solid of harvested fruit in J-2, J-3 and J-1 films were higher than whose in K-1 film. Marketable yields in J-2, J-3 and J-1 films were higher in order.