• 한국작물학회지
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• 제20권
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• pp.69-73
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• 1975

방사선후처리로서 산소가 수분함량이 다른 수도종자에 미치는 영향을 조사코저 수분함량 5.6∼14.7%까지의 종자에 3∼25kR의 방사선량을 조사한 후 산소 및 질소로 bubbling한 상태에서 hydration처리하였다. 효과가 현저하여 5.6∼12.9%까지는 산소처리에 의한 묘장 및 생존율의 감소가 나타났지만 13.9%부터 그 이상에서는 차이가 없었다. 엽록소돌연변이율 및 불임율은 6.5%의 저수분에서 13.0%의 고수분함량에 이르기까지 공히 산소처리에 의한 영향이 있었고 특히 저수분함량일수록 또는 방사선량이 높을수록 그차이는 현저하였다.

• 한국환경보건학회지
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• 제28권2호
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• pp.71-80
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• 2002

To evaluate the skin toxicity of topical cyclohexane application (25mg/$\textrm{cm}^2$) was sequentially applied to the rat skin for four days. On the histopathological findings in the light micrographs, neutrophils and engulfed neutrophils are seen, and many cytoplasmic processes were appeared in proliferated layer whereas in the dermis area, increased numbers of fibroblast, accumulation of neutrophil and lipid droplets are demonstrated. On the other hand, applying the cyclohexane to the rat skin led to the remarkable rise of cutaneous xanthine oxidase activity and similar activities of superoxide dismutase and glutathione peroxidase and glutathione content and declined activity of glutathione S-transferase compared with control group. Especially the remarkably decreased activity of aniline hydroxylase (AH) was appeared in skin as little as scarcely determined. Furthermore, the applying the cyclohexane to skin led to the significantly increased activity of hepatic AH and alcohol dehydrogenase. These results indicate that oxygen free radical and intermediate metabolite of cyclohexane may be responsible for structural changes in skin by cyclohexane application to rat skin.

• Preventive Nutrition and Food Science
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• 제3권1호
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• pp.67-70
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• 1998

To investigate an effect of Gam-Roa tea on the free radical or alcohol detoxicating enzyme activities, the rats got a drink at the Gam-Roa tea instead of water for 3 months, and then the animals were sacrificed and obtained the following findings. The animals receiving Gam-Roa tea showed a decreasing tendency of hepatic xanthine oxithine oxidase activity and significantly incresed content of cytochrome P-450 compared with the control. Furthermore, hepatic superoxide dismutase and glutathione S-transferase activities were also more increased in rats received Gam-Roa tea than in the control group, those receiving water. On the other hand, alcohol or aldehyde dehydrogenase activities were more increased in rats receiving Gam-Roa tea than the control. In conclusion, it is likely that the liver of rats receiving Gam-Roa tea may have the oxygen free radical or alcohol detoxication potential.

• 한국전기전자재료학회논문지
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• 제25권9호
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• pp.717-722
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• 2012

In this work, we study on the effects of the oxygen pressure on the structural and crystalline of MgZnO thin films. MgZnO thin films were deposited on p-Si (111) substrates by using pulsed laser deposition. The X-ray diffraction analysis and energy-dispersive X-ray results revealed that as the oxygen pressure increased and Mg content in the MgZnO films decreased. Also Crystal structure was changed from cubic rock salt to hexagonal wurtzite. Alpha step and atomic force microscopy results showed that the thickness of the films are about 100 nm, and it has been found that the MgZnO (002) preferred orientation were deposited with increasing the oxygen pressure. Therefore, the effect of the preferred orientation, the crystallization grew in the form of the columnar; Grain size and RMS of the films were increased with increasing oxygen pressure.

• 한국광학회지
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• 제18권2호
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• pp.171-177
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• 2007

전자빔 증착법을 이용하여 산소 분압에 따라 $TiO_2$ 박막을 제작하고, 열처리 온도에 따른 박막의 구조적 특성과 광학적 특성을 분석 하였다. $TiO_2$ 박막들의 물리적 특성은 주입된 산소량에 의존하였다. 주입된 산소량이 증가 할수록 상전이 온도가 높아지고, 가시광선 영역에서 $TiO_2$ 박막의 투과율이 증가하였다. 그리고 주입된 산소량이 작은 경우, $700^{\circ}C$에서 $1100^{\circ}C$로 열처리 후 $TiO_2$ 박막의 흡수단 이 좀더 장파장으로 이동하였다.

• 한국포장학회지
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• 제15권2호
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• pp.49-54
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• 2009

레토르트 삼계탕은 장기간 저장되는 제품이므로 포장 불량률을 가능한 한 최소화하는 것이 품질 안전과 소비자 식중독 문제를 방지하기 위해서 중요한 사안이다. 따라서 업계에서는 현행 사용되는 삼계탕용 포장재를 이용하여 저장 시험을 병행하되 기존 포장재의 물성을 표준화하고, 아울러 포장작업시 가능한 한 포장내 잔존산소량이 낮게 유지되는 포장방법을 동원하고, 봉함부위가 오염되지 않도록 유의하며 멸균 후 열봉함강도가 낮아지는 것을 감안하여 포장재 스펙을 결정하는 방안이 강구되어져야 할 것이다. 이를 위해서는 가능한 한 포장내 잔존산소량을 줄이기 위하여 포장내 headspace를 줄이거나 질소 등 비활성기체를 주입 후 포장하는 것이 바람직하겠다. 그러나 현행 업계에서 삼계탕을 질소치환포장하는 것이 공정의 속도와 운용비용 등을 고려할 때 쉽지 않을 것으로 판단된다. 따라서 삼계탕 포장시 육수의 충진온도는 최소한 85이상 가열된 상태로 주입하고, 주입시 열봉함부위가 오염되지 않도록 유의하며, 필요하면 guide bar등과 같은 보조 장치를 설치하거나 파우치 밀봉 전 headspace를 압착하는 기술, 그리고 파우치 하부의 유사핀홀 현상을 방지하기 위한 보호대를 설치하여 육수를 충진하는 기술 등을 적용하는 것이 바람직할 것으로 사료된다. 그리고 멸균 처리 후 봉함강도가 감소하는 만큼 이를 감안하여 포장재의 선택과 포장작업이 이루어져야 할 것으로 판단된다.

• 한국해양학회지
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• 제5권1호
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• pp.14-29
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• 1970

김의 성장과 품질에 대한 환경수질의 중요성은 다시 말할 필요가 없다 김 양식기에 있어서의 환경수질의 변동을 보기 위해 저자의 한 사람은 섬진강 및 낙동강 하구 김밭에 대해 이미 조사한 바 있거니와 이번에는 우리나라 유수의 김 생산지인 완도군하 김밭의 수질을 전보와 같은 방법으로 조사하였다. 조사지점으로서는 완도군 에서대체로 대표적 김밭이라 볼 수 있는 두 지점을 선정하여 1968년 10월부터 1969년 2월까지 매월 대조일에서의 수질변동을 조수의 일조기에 걸쳐 1시간마다 각 성분량을 측정하므로써 조사하였다.

• 한국식품조리과학회지
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• 제33권1호
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• pp.113-120
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• 2017

Purpose: Lipid autoxidation of a soybean oil-in-water emulsion with high oil content was studied under after basil extract and/or iron addition. Methods: The emulsion consisted of tocopherol-stripped soybean oil (40 g), citrate buffer (60 g, pH 4.0), and/or $FeSO_4$ (0.5 mg) with 75% ethanol extract (200 mg/kg) of basil (Ocimum basilicum). Lipid oxidation was evaluated using headspace oxygen content, hydroperoxide contents, and p-anisidne values of the emulsion. Polyphenol compound retention in the emulsion during oxidation was determined spectrophotometrically. Results: Addition of basil extract significantly (p<0.05) decreased reduced hydroperoxide contents of the emulsion, and iron significantly (p<0.05) increased anisidine values and decreased oxygen contents. Co-addition of basil extract and iron showed significantly (p<0.05) lower reduced hydroperoxide contents in the emulsion than compared to those of the emulsion with added iron and the control emulsion without basil extract nor or iron. During the emulsion oxidation, polyphenol compounds in the emulsion with added basil extract were degraded, but more slowlywhich was slowed degraded in the presence of iron. Conclusion: The iIron increased the lipid oxidation through hydroperoxide decomposition, and basil extract showed antioxidant activity through radical-scavenging and iron-chelation. Polyphenol degradation was decelerated by iron addition, which suggested suggests iron chelation may be more preferred topreferentially activated over radical scavenging in the antioxidant action by of basil extract in the oil-in-water emulsion with high oil content.

• 대한약리학회지
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• 제32권2호
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• pp.201-209
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• 1996

Restoration of the blood flow after a period of ischemia is accompanied by generation of toxic oxygen radicals. This phenomenon may account for the occurrence of reperfusion-mediated tissue injury in ischemic hearts. In in vitro studies, although oxygen radicals can be generated from a variety of sources, including xanthine oxidase system, activated leucocytes, mitochondria and others, the most important source and mechanism of oxygen radical production in the post-ischemic reperfused hearts is unclear. In the present study, we tested the hypothesis that the respiratory chain of mitochondria might be an important source of oxygen radicals which are responsible for the development of the reperfusion injury of ischemic hearts. Langendorff-perfused, isolated rat hearts were subjected to 30 min of global ischemia at $37^{\circ}C$, followed by reperfusion. Amytal, a reversible inhibitor of mitochondrial respiration, was employed to assess the mitochondrial contributions to the development of the reperfusion injury. Intact mitochonria were isolated from the control and the post-ischemic reperfused hearts. Mitochondrial oxygen radical generation was measured by chemiluminescence method and the oxidative tissue damage was estimated by measuring a lipid peroxidation product, malondialdehyde(MDA). To evaluate the extent of the reperfusion injury, post-ischemic functional recovery and lactate dehydrogenase(LDH) release were assessed and compared in Amytal-treated and -untreated hearts. Upon reperfusion of the ischemic hearts, MDA release into the coronary effluent was markedly increased. MDA content of mitochondria isolated from the post-ischemic reperfused hearts was increased to 152% of preischemic value, whereas minimal change was observed in extramitochondrial fraction. The generation of superoxide anion was increased about twice in mitochondria from the reperfused hearts than in those from the control hearts. Amytal inhibited the mitochondrial superoxide generation significantly and also suppressed MDA production in the reperfused hearts. Additionally, Amytal prevented the contractile dysfunction and the increased release of LDH observed in the reperfused hearts. In conclusion, these results indicate that the respiratory chain of mitochondria may be an important source of oxygen radical formation in post-ischemic reperfused hearts, and that oxygen radicals originating from the mitochondria may contribute to the development of myocardial reperfusion injury.

• 공업화학
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• 제7권3호
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• pp.554-564
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• 1996

페롭스카이트 $La_{0.6}Sr_{0.4}Co_{1-x}Fe_xO_3$(x=0.00, 0.01, 0.10, 0.20, 0.35, 및 0.50)를 산소전극물질로 사용하여 알칼리형 연료전지에서의 산소환원반응을 연구하였다. Fe치환에 따른 촉매특성의 변화를 X-선회절분석법(XRD), 열중량분석법(TG) 및 승온환원법(TPR)을 통하여 조사하였다. XRD 구조분석을 통하여 페롭스카이트 단위격자의 격자상수값을 측정할 수 있었다. TG 실험결과 Fe는 페롭스카이트 구조내에서 크게 안정화되어 $900^{\circ}C$까지 거의 환원되지 않았고, Fe치환량 증가에 따라 Co-O간의 결합에너지가 증가하여 고온에서 제거되는 산소종의 양이 증가하였다. TPR 실험결과, ${\alpha}$-(저온피크)와 ${\beta}$-(고온피크)산소종이 존재하였다. ${\beta}$-산소종은 Co와 강하게 결합되어 있는 산소종으로서 Fe치환량 증가에 따라 결합세기가 증가하였다. ${\alpha}$-산소종은 가역적으로 격자내외를 출입하는 산소환원반응의 활성종이었으며, Fe치환량 증가에 따른 격자상수의 증가는 금속과 ${\alpha}$-산소종간의 결합에너지로 볼 수 있는 ${\alpha}$산소종의 환원피크를 저온으로 이동시킴으로써 산소환원반응의 활성을 증가시켰다. 반면에, Fe치환량 증가에 따른 ${\alpha}$-산소종의 감소는 산소환원반응의 활성을 감소시켰으며, Fe치환에 따른 표면적의 증가는 반응활성에 크게 영향을 미치지 못하였다.