• 한국전기전자재료학회논문지
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• 제21권9호
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• pp.789-794
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• 2008

Zinc oxide (ZnO) has been widely studied for its practical applications such as transparent conduction electrodes for flat panel displays and solar cells. Especially, ZnO films show good chemical stability against hydrogen plasma, absence of toxicity, abundance in nature, and then suitable for photovoltaic applications. However, the fabrication process of thin film solar cells require a high substrate temperature and/or post heat treatment. Therefore, the layers have to withstand high temperatures, requiring an excellent stability without degrading their electronic and optical properties. In this paper, we investigated the stability of zinc oxide (ZnO) films doped with aluminum and hydrogen. Doped ZnO films were prepared by r.f. magnetron sputter and followed by heat treatment at different temperatures and for various times.

• 한국식품과학회지
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• 제17권2호
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• pp.121-127
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• 1985

Ciguatoxin 구조 연구의 일환으로 파랑비늘돔 중에 서 독성분을 추출하였는데 Scarus sordidus만 근육과 내장에 독이 있었으나, S.frenatus, S.scaber and S.pectorlis에는 모두 독이 없었다. 실리스산컬럼에서 얻은 조독을 DEAE-셀루로즈 컬럼상에서 콜로로포름, 클로로포름-메타놀 (1 : 1) 및 메타놀로 전개하였더니 클로로포름 유출액(ST-1) 과 클로로포름-메타놀(1 : 1) 유출액에서 독성분이 발견되었고, 메타놀 유출액에서는 독성분이 검출되지 않았다. ST-1과 ST-2을 silica gel 60F-254에 spot하여 클로로포름-메타놀-물-식초산 (90 : 9.5 : 0.2 : 0.3)으로 전개하였더니, 그Rf값이 각각 0.60-0.75, 0.30-0.54였다. DEAE-셀루로즈 컬럼에서 얻은 ST-1을 재재크로마토그라피 하여도 역시 ST-1과 ST-2로 나누어졌다. 이렇게 얻은 ST-1과 ST-2는 세파텍스 LH-20에 흡착시켜, 클로로포름-메타놀(1 : 1) 용매로 전개할 때, 머무름시간이 모두 같았고, 역상 LiChrosorb RP-18를 이용한 HPLC상에서도 머무름시간이 동일하였다. 또 순수한 $ST-1\;(1.10\;{\mu}g)$ 그리고 이것을 1 N NaOH로 처리한 것 $(1.13\;{\mu}g)$을 활성도V인 알루미나 컬럼에 흡착시켜 클로로포름-메타놀 혼합액으로 전개하였더니 알카리처리를 하지 않는 경우는 $0.35\;{\mu}g)$가 클로로포름-메타놀의 9 : 1, 1 : 1 유출액에서, $(0.55\;{\mu}g)$가 메타놀-물 (1 : 1) 유출액에서 검출되었으나, 알카리처리를 한 경우는 처음 독성의 50%가 소실되어, 클로로포름-메타놀 (9 : 1) 유출액에서 $(0.21\;{\mu}g)$, 메타놀-물 (1 : 1) 유출액에서 $(0.80\;{\mu}g)$ 검출되었다. 하면 morey eel내장에서 얻은 독물질도 DEAE-셀루로즈에서 ST-1 과 ST-2로 나누어지며, 이 ST-1의 TLC, HPLC 및 알루미나 컬럼상의 거동이 파랑비늘돔에서 얻은 ST-1의 그것과 같으므로 scaritoxin으로 보고한 ST-1은 ciguatoxin의 형태인 less polar cigutoxin (LPCTX) 으로 생각된다.

• 한국태양에너지학회 논문집
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• 제32권spc3호
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• pp.194-198
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• 2012

Crystalline silicon solar cell remains the major player in the photovoltaic marketplace with 80% of the market, despite the development of various thin film technologies. Silicon's excellent efficiency, stability, material abundance and low toxicity have helped to maintain its position of dominance. However, the cost of silicon materials remains a major barrier to reducing the cost of silicon photovoltaics. Using the crystalline silicon wafer with thinner thickness is the promising way for cost and material reduction in the solar cell production. However, the thinner the silicon wafer is, the worse bow phenomenon is induced. The bow phenomenon is observed when two or more layers of materials with different temperature expansion coefficiencies are in contact, in this case silicon and aluminum. In this paper, the solar cells were fabricated with different thicknesses of Al layer in order to reduce the bow phenomenon. With less amount of paste applications, we observed that the bow could be reduced by up to 40% of the largest value with 120 micron thickness of the wafer even though the conversion efficiency decrease by 0.5% occurred. Since the bowed wafers lead to unacceptable yield losses during the module construction, the reduction of bow is indispensable on thin crystalline silicon solar cell. In this work, we have studied on the counterbalance between the bow and conversion efficiency and also suggest the formation of enough back surface field (BSF) with thinner Al layer application.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.108-112
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• 2012

Crystalline silicon solar cell remains the major player in the photovoltaic marketplace with 90 % of the market, despite the development of a variety of thin film technologies. Silicon's excellent efficiency, stability, material abundance and low toxicity have helped to maintain its position of dominance. However, the cost of silicon photovoltaic remains a major barrier to reducing the cost of silicon photovoltaics. Using the crystalline silicon wafer with thinner thickness is the promising way for cost and material reduction in the solar cell production. However, the thinner thickness of silicon wafer is, the worse bow phenomenon is induced. The bow phenomenon is observed when two or more layers of materials of different temperature expansion coefficiencies are in contact, in this case silicon and aluminum. In this paper, the solar cells were fabricated with different thicknesses of Al layer in order to reduce the bow phenomenon. With lower paste applications, we observed that the bow could be reduced by up to 40% of the largest value with 130 micron thickness of the wafer even though the conversion efficiency decrease of 0.5 % occurred. Since the bowed wafers lead to unacceptable yield losses during the module construction, the reduction of bow is indispensable on thin crystalline silicon solar cell. In this work, we have studied on the counterbalance between the bow and conversion efficiency and also suggest the formation of enough back surface field (BSF) with thinner Al paste application.

• 한국환경보건학회지
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• 제42권1호
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• pp.27-33
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• 2016

Objectives: Alumina nanoparticles ($Al_2O_3$, Al-NPs) are used for various purposes, including as coating agents and paint additives. Their potential toxicity has raised concern for human health. This study focuses on exploring the toxic effects on the brain and kidneys caused by Al-NPs exposure in rats. Methods: The animals were orally administered Al-NPs at 10, 50 and 100 mg/kg body weight for 28 days following OECD TG 407. To determine the targeted toxicity of Al-NPs, histopathological examination and gene expression analysis were conducted on the rats. Results: The Al-NPs treatment induced kidney tubular dilatation. In the rat cerebrums, the expression levels of 126 genes experienced two-fold or greater increases in response to Al-NPs, including other genes encoding proteins involved in cell differentiation, transcription and signal transduction. In the rat kidneys, the expression levels of 152 genes also showed two-fold or greater increases in response to Al-NPs, including other genes encoding proteins involved in apoptosis, transcription and signal transduction. Conclusion: These results suggest that exposure to Al-NPs influences cellular signal pathways of kidney and cerebrum, and it can be a toxic indicators of nanometrials.

• 한국토양비료학회지
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• 제37권4호
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• pp.212-219
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• 2004

도로공사 후 발생되는 절개지 암사면의 토양 침시방지와 조기 식생도입을 위하여 시공되는 인공배양토가 산성 지하수에 노출되었을 때 나타나는 perennial ryegrass의 생육저해 원인을 조사하였다. Perennial ryegrass가 정상적으로 자라는 지역과 피해가 발생한 지역에서 각각 채취한 인공배양토의 화확적 특성과 인공배양토 추출물들에 대한 라이그래스 생육반응에는 현저한 차이가 없었다. 그러나 인공배양토를 시공한 후 피해가 발생한 지역의 배경토양은 정상지역의 배경토양에 비해 pH가 매우 낮고(pH 3.6), 추출성 철과 알루미늄의 함량이 현저하게 높았으며, 피해지역에서 채취한 토양의 물 추출물에 대한 라이그래스의 발아 및 뿌리 생육은 심한 저해 현상을 보였다. 피해지역에서 채취한 인공배양토와 배경토양에 대한 X-ray 분석결과 각각의 시료에서 jaroslte가 발견되었으며, 이는 라이그래스 생육저해의 원인이 피해지역 인근에서 용출되는 pyrite를 함유하는 산성지하수(pH 3.3)에 기인함을 암시한다. $Al^{3+}$과 $Fe^{2+}$, $Fe^{3+}$ 표준용액을 이용하여 라이그래스의 뿌리생장율을 50% 수준까지 감소시키는 $EC_{50}$값을 조사한 결과, 산성지하수와 유사한 pH 환경(pH 3.3)에서 라이그래스에 대한 $Al^{3+}$과 $Fe^{2+}$, $Fe^{3+}$의 $EC_{50}$값은 자각 0.5, 0.3, 19 mM 이었다. 이러한 결과는 산성 환경하에서는 매우 낮은 $Al^{3+}$과 $Fe^{2+}$ 농도수준에서 조차 라이그래스의 생장이 현저히 억제될 수 있으며, 산성지하수에 포함된 pyrite에 기인하는 낮은 pH, $Al^{3+}$과 $Fe^{2+}$ 이온용액이 라이그래스 생장저해의 직접적인 원인임을 의미한다.

• 대한임상검사과학회지
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• 제49권1호
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• pp.8-14
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• 2017

치매유발제인 $AlCl_3$에 대한 rosmarinic acid의 영향을 알아보기 위하여 뇌세포종인 배양 C6 glioma 세포를 배양한 후 세포생존율을 비롯한 전자공여능(electron donating ability, EDA), SOD-유사활성(superoxide dismutase-like activity) 및 지질과산화(lipid peroxidation) 억제능을 조사하였다. 본 연구에서 $AlCl_3$는 배양 세포에 농도 의존적으로 세포생존율을 대조군에 비하여 유의하게 감소시킴으로서 세포독성을 나타냈다. 또한, $AlCl_3$의 $XTT_{50}$값이 $142.2{\mu}M$에서 나타남으로 이는 Borenfreund와 Puerner의 독성판정기준에 의하여 중간독성(mid-toxic)인 것으로 나타났다. 한편, rosmarinic acid가 $AlCl_3$에 미치는 영향에 있어서, $40{\mu}M$ rosmarinic acid 처리에서는 $AlCl_3$만의 처리에 비하여 세포생존율을 유의하게 증가시킴으로서 $AlCl_3$의 산화적 손상으로부터 세포손상을 보호하였다. 또한 rosmarinic acid는 전자공여능을 비롯한 SOD-유사활성 및 지질과산화의 억제효과를 보임으로서 항산화능을 나타냈다. 이상의 결과로 부터 산화적 손상이 $AlCl_3$의 독성에 관여하고 있으며, rosmarinic acid는 항산화능에 의하여 $AlCl_3$의 독성을 효과적으로 방어하였다. 따라서, rosmarinic acid와 같은 천연성분은 치매와 같이 산화적 손상과 관련된 병변의 치료적 개선을 위한 천연 소재로서의 가능성을 제시하였다.

• 대한수의학회지
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• 제46권3호
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• pp.215-224
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• 2006

In order to search the availability of the lectin extracted from Korean mistletoe(Viscum album coloratum) as an adjuvant for the avian vaccines, attempts were made to determine toxicity of the lectin in chicks and its immunostimulating activity on the inactivated vaccines against Newcastle disease virus(NDV). For the determination of toxicity, the lectin was injected into the thigh muscle of SPF chicks(Charles River) of 1-week-old and observed hematologically and pathologically. For the determination of immunostimulating effects, lectin-adjuvanted, inactivated NDV vaccines were injected into the thigh muscle of SPF chicks in the same age group. Sera of the chicks were examined for the hemagglutination-inhibition(HI) antibodies induced, their HI titers and reaction to the NDV antigens. The data were further compared with those from aluminum hydroxide [$Al(OH)_3$]-adjuvanted vaccines and vaccines without adjuvant, and the results are as follows. There were no significant changes observed in the values of RBC, WBC, Hb, PCV, MCV, MCH, MCHC, AST, ALT, BUN, creatinine and total proteins in the chicks administered with lectin of 1.1, 2.2 and $22.2{\mu}g/kg$ body weight, which means the lectin has no effects on blood values and functions of liver and kidney. In histopathologic observation, no lesions were observed in the brain, heart, liver, lung, spleen, kidney, thymus and bursa of Fabricius of the chicks administered with lectin of 1.1, 2.2 and $22.2{\mu}g/kg$ body weight. There were inflammatory lesions, such as congestion, hemorrhage, edema, infiltration of macrophages and coagulation necrosis observed in the thigh muscle of chicks administered with lectin of $22.2{\mu}g/kg$ body weight, whereas no changes were observed in 1.1 and $22.2{\mu}g/kg$ lectin administered chicks. In chicks immunized with lectin($4.4{\mu}g/kg$ of body weight)-adjuvanted B1, LaSota and Ulster 2C vaccines, HI titers in reciprocal values for $log_2$ were 1.8-2.2 at 1 week after vaccination, which was similar with those of 1.5-2.9 by $Al(OH)_3$-adjuvanted vaccines. The HI titers by the lectin-adjuvanted vaccines reached to 3.9-5.3 at 4 weeks, whereas those by the $Al(OH)_3$-adjuvanted vaccines were more high as 7.3-9.3. Meanwhile, the immunostimulating effects of the lectin were recognized while compared to the HI titers with 2.4-3.7 in chicks immunized with vaccines without adjuvants at 4 weeks after vaccination. The chicks immunized with lectin-adjuvanted vaccines were enough to resist challenges by Kyojeongwon strain, a very virulent NDV at 4 weeks after vaccination as well as chicks immunized with $Al(OH)_3$-adjuvanted vaccines. The HI titers by the lectin-adjuvanted vaccines reached to high level as 8.7-10.3 as those with 8.2-9.6 by the $Al(OH)_3$-adjuvanted vaccines at 6 weeks after vaccination, which may be the booster effects by the challenge virus. Antibodies specific to the HN and F antigens of NDV were observed in the sera of both chicks immunized with lectin-adjuvanted vaccines and $Al(OH)_3$-adjuvanted vaccines.

• Journal of Acupuncture Research
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• 제35권1호
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• pp.41-45
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• 2018

Background: Danggwisusan is a herbal medicine which is used to treat bruises, static blood, external injuries, and somatalgia in Korean medicine. The objectives of this study were to investigate whether Danggwisusan hot aqueous extract had an inhibitory effect upon inflammatory cytokine production and oxidation. Methods: Cytotoxic activity of Danggwisusan extract was examined by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay. The amount of nitric oxide produced was measured using Griess reagent. Prostaglandin E2 production was measured using an enzyme immunoassay. Inflammatory cytokines ($IL-1{\beta}$, IL-6 and $TNF-{\alpha}$) were measured by an enzyme linked immunosorbent assay. The anti-oxidative effect of Danggwisusan was measured by the 1,1-Diphenyl-2-picryl hydrazyl method. The amount of polyphenol and flavonoid contents were measured by Folin and Ciocalteauea phenol reagent and aluminum nitrate. Results: Danggwisusan hot aqueous extracts did not show significant toxicity at 10, 20, 50, and $100{\mu}g/mL$. At a dose of $100{\mu}g/mL$, Danggwisusan hot aqueous extract significantly inhibited nitric oxide and $PGE_2$ production, and significantly reduced $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ production. At a dose of $100{\mu}g/mL$, 1,1-Diphenyl-2-picryl hydrazyl free radical scavenging capability was over 50%. Conclusion: This study showed that Danggwisusan hot aqueous extract may have anti-inflammatory and anti-oxidative effects on macrophages.

• 농약과학회지
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• 제15권2호
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• pp.194-200
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• 2011

배추좀나방(Plutella xylostella L.)은 세계적으로 배추과 작물의 가장 문제 해충이다. 지금까지 배추좀나방 방제는 유충을 대상으로 이루어졌으나, 더욱 효과적인 방제를 위해서 알의 부화를 억제하거나 살란활성을 가진 새로운 살충제 개발이 요구된다. 이에 알루미늄 호일을 활용하여 배추좀나방의 살란활성을 효율적으로 생물검정하는 방법을 개발하였다. 알루미늄호일($4{\times}12$ cm, 산란호일)에 배추잎 즙액을 도포하여 아크릴원통에 넣고 갓 우화한 성충 300마리를 24시간 접종한 결과 알을 충분하게 확보할 수 있었으며, 이는 4일간 연속으로 채란 가능하였다. 살란활성 검정은 난괴 크기별로 산란호일을 6~12조각으로 나눈 농도별로 준비된 메탄올 용액에 2~10초간 핀셋으로 침지한 후 음건(15~30분)하여 소형사육통에 넣어 부화율을 조사하였다. 산란호일은 50% 메탄올에 10초간 침지하여도 활성검정에 어떠한 영향도 미치지 않았다. 하지만 소형 사육통의 뚜껑을 개폐하면 활성물질의 성질에 따라 영향을 받았다 이러한 방법으로 식물체 50종의 메탄올 추출물에 대한 배추좀나방 살란활성을 검정한 결과, 고본(Angelica tenuissima) 뿌리, 원지(Polygala tenuifolia) 뿌리, 지골피(Lycium chinense) 뿌리, 천궁(Cnidium officinale) 뿌리 등은 90% 이상의 높은 살란활성을 나타내었다.