• 한국작물학회지
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• 제42권3호
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• pp.338-343
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• 1997

벼 품종의 오존 저항성 판단을 위한 시험에서 오존의 처리농도는 0.3 ppm이 0.1 ppm보다 뚜렷한 결과를 보였고, 처리시간은 2∼4시간이 알맞은 것으로 나타났다. 묘대일수에 따른 저항성 정도는 파종후 3주까지는 생육이 진전될수록 높아지는 경향이었으나 3∼5주간에는 큰 차이가 없었다. 인디카와 통일형 품종들이 자포니카 품종보다 저항성이 높은 경향이었고, 자포니카 품종 중에서 장안벼외 7 품종은 높은 저항성을 나타내었다. 벼의 생육시기에 따른 피해엽율은 간척벼는 유묘기에서 밀양 2003외 4 품종은 최고 분열기에서 가장 높게 나타났고 임실율은 수잉기 처리에서 가장 낮았다.

• Toxicological Research
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• 제17권1호
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• pp.1-6
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• 2001

To determine whether ozone is genotoxic at environmentally relevant exposure level, B6C3F1 mice were exposed to 0.5 ppm ozone for 12 weeks, 6 hr/day. Chromosomal aberration, supravital micronucleus and hprt mutation assays were performed. The percentage of abnormal cells was significantly increased at 0.5 ppm ozone when compared to unexposed control in chromosome aberration assay. Significant increase in the frequencies of micro nucleated reticulocytes and 6-thioguanine-resistant ($TG^r$) lymphocytes was also observed in supravital micronucleus assay using peripheral blood and lymphocyte hprt mutation assay, respectively. The results indicate, that under our experimental conditions, 0.5 ppm ozone are genotoxic in exposed B6C3F1 mice.

• Carbon letters
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• 제11권4호
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• pp.298-303
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• 2010

A method of functionalization of multi-walled carbon nanotube (MWNT) at room temperature using dry ozone gas is described. The resulting MWNT were characterized by Fourier transform infrared, x-ray photoelectron spectroscopy, and scanning electron microscopy. Combined to these analyses and solubility in liquids, it could be concluded that the dry ozone gas exposure introduces polar functional groups such as carboxylic groups to MWNT similar to acidic modification of MWNT. Particularly, the stable dispersion of MWNT in water after ozone treatment above a critical level could be obtained, implying potential bio-application. The hydrophilic functional groups on the MWNT introduced by ozone oxidation were helpful in improving the interaction with functional groups in PA6 such as $-NH_2$ and -CONH- resulting in improved mechanical properties.

• Journal of Korean Society for Atmospheric Environment
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• 제22권E2호
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• pp.89-98
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• 2006

Two tobacco cultivars (Nicotiana tabacum L.), Bel-B and Bel-W3, tolerant and sensitive to ozone, respectively, were grown in a greenhouse supplied with charcoal filtered air and exposed to 200 ppb ozone for 4 hr. Effects on chlorophyll fluorescence, net photosynthesis, and stomatal conductance are described. Quantum yield was calculated from chlorophyll fluorescence and the initial slope of the assimilation-light curve measured by the gas exchange method. Only the sensitive cultivar, Bel-W3, developed visual injury symptoms on up to 50% of the $5^{th}$ leaf. The maximum net photosynthetic rate of ozone-treated plants was reduced 40% compared to control plants immediately after ozone fumigation in the tolerant cultivar; however, photosynthesis recovered by 24 hr post fumigation and remained at the same level as control plants. On the other hand, ozone exposure reduced maximum net photosynthesis up to 50%, with no recovery, in the sensitive cultivar apparently causing permanent damage to the photosystem. Reductions in apparent quantum efficiency, calculated from the assimilation-light curve, differed between cultivars. Bel-B showed an immediate depression of 14% compared to controls, whereas, Bel-W3 showed a 27% decline. Electron transport rate (ETR), at saturating light intensity, decreased 58% and 80% immediately after ozone treatment in Bel-B and Bel-W3, respectively. Quantum yield decreased 28% and 36% in Bel-B and Bel-W3, respectively. It can be concluded that ozone caused a greater relative decrease in linear electron transport than maximum net photosynthesis, suggesting greater damage to PSII than the carbon reduction cycle.

• The Plant Pathology Journal
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• 제16권3호
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• pp.130-136
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• 2000

Differences in physiological and biochemical responses between sensitive and tolerant rice cultivars to ozone were investigated to develop reliable indications of early ozone damage. Three Korean local rice cultivars -sen-sitive cultivar Dongjin (DJ), moderately tolerant cultivar Hwayeong (HY) and tolerant cultivar Ilmee (IM) were exposed to ozone at the concentrations of 100 nl $\textrm{l}^{-1}$ or 200 nl $\textrm{l}^{-1}$ , 8 h per day for 10 days in a controlled-environment fumigation chamber. The rice cultivars seemed to be endurable to ozone stress at the concentration of 100 nl $\textrm{l}^{-1}$ which is frequently monitored during the growing season in summer. However, severe damage was induced and differential sensitivity was clearly noted among the rice cultivars at the higher ozone concentration. Activation of the glutathion (GR) -ascorbate peroxidase (APX) cycle was likely to be responsible for protection of rice plants against ozone exposure, relating difference in sensitivity of rice cultivars to ozone. Photosynthetic activity appeared to be one of sensitive responses, for which chlorophyll fluorescence and leaf greenness can together provide a very reliable index, a degree of photosynthetic damages by ozone. Formation of malondialdehyde (MDA) was also considered as an indication that can differentiate cultivars sensitivity to ozone. However, the changes in polyamines and total phenolics were not consistent with exposed ozone concentrations and/or ozone sensitivity of the cultivars. The behavior of polyamines and phenolics in the damaged plants at high ozone levels could be interpreted as an indication of ozone injury rather than activation of additional protection mechanisms scavenging active oxygen species formed by ozone. Several responses triggered by ozone could explain the differential sensitivity of the rice cultivars and be used as reliable indications of relative ozone damage to rice plant.

• 한국농림기상학회지
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• 제4권2호
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• pp.72-79
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• 2002

자작나무류 4개 수종의 오존에 대한 생리 생화학적인 반응 특성을 비교하고, 수종별 오존 홉입량과 광합성 능력 및 항산화효소 활성간의 연관성을 찾기 위하여 거제수나무, 물박달나무, 자작나무, 사스래나무 묘목에 5주 동안 100 ppb 오존을 노출시킨 후 오존 흡입량, 광합성, SOD, GR 활성을 측정하였다. 5주 동안의 누적 오존 흡입량은 거제수나무가 53.8 mmol m$^{-2}$ 로 가장 많았으며, 물박달나무가 35.5 mmol m$^{-2}$ 로 가장 적었다. 오존에 노출된 4개 수종의 광합성 능력은 감소하였으나 기공전도도에 따른 광합성 반응은 수종간 달랐다. 4개 수종의 SOD 활성은 누적 오존 홉입량이 증가함에 따라 증가하다가 감소하였다. GR 활성은 거제수나무의 경우 SOD 활성과 마찬가지로 점차 증가하다가 감소하였으나, 다른 세 수종은 누적 오존 흡입량이 증가하면서 지속적으로 증가하였다. 결론적으로 거제수나무는 누적 오존 흡입량의 증가로 SOD와 GR 활성을 잃어버리는 민감성 수종으로 나타났으나, 다른 세 수종은 GR 활성을 지속적으로 증가시키는 저항성을 보였다. 또한 오존 흡입량에 따른 SOD와 GR 활성 반응은 반드시 일치하지 않으며, 수종별 반응 차이는 오존 흡입량에 큰 영향을 받는 것으로 판단되었다.

• 한국환경농학회지
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• 제1권2호
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• pp.123-128
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• 1982

수도(水稻)(서광(曙光)벼)의 활착기(活着期), 분고최성기(分藁最盛期), 유수형성기(幼穗形成期), 출수기(出穗期)때에 ozone가스 0.5ppm을 4시간(時間)씩 가스접촉실내(接觸室內)에서 접촉(接觸)시켜 가스접촉후(接觸後)에 나타나는 피해증상(被害症狀), 피해엽률(被害葉率), 엽록소함양(葉綠素含量) 및 peroxidase의 활성(活性)을 조사(調査)한 결과(結果)는 다음과 같다. 1) Ozone 가스에 의(依)한 수도엽(水稻葉)의 피해증상(被害症狀)은 은백색(銀白色)의 미세(微細)한 반점(斑點)이 엽맥(葉脈)을 따라 발생(發生)되며, 적갈색(赤褐色)${\sim}$암갈색(暗褐色)의 반점(斑點)이 발생(發生)되는 경우(境遇)도 있었다. 2) Ozone가스 접촉(接觸)에 의(依)한 수도(水稻)의 생육시기별 감수정도(生育時期別 減收程度)는 분고최성기(分藁最盛期)>유수형성기(幼穗形成期)>활착기(活着期)>출수기(出穗期)의 순(順)이었다. 3) Ozone가스 접촉(接觸)에 의(依)한 수도(水稻)의 생육시기별 피해엽률(生育時期別 被害葉率) 및 엽록소감소정도(葉綠素減少程度)는 분고최성기(分藁最盛期)>활착기(活着期)>유수형성기(幼穗形成期)>출수기(出穗期)의 순(順)이었다. 4) Ozone가스 접촉(接觸)으로 수도엽중(水稻葉中)의 실소함량(室素含量)이 감소(減少)되었고 도체엽중 실소함량(稻體葉中 室素含量)이 높은 시기(時期)에 피해(被害)가 컷다.

• The Plant Pathology Journal
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• 제18권1호
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• pp.43-49
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• 2002

Direct effects of atmospheric ozone on conidia of the rice blast pathogen, Magnaporthe grisea, were investigated to evaluate ozone-induced effects on infection potential of the rice blast fungus. Acute ozone exposure (200 nl $1^{-1}$, 8 h $day^{-1}$3 days) during sporulation significantly affected conidial morphology, appressorium formation, and disease development on rice loaves. Ozone caused reduction in conidial size and change in conidial shape. Relative cytoplasmic volume of lipids and vacuoles were increased in ozone-exposed conidia. Inhibition of appressorium formation and simultaneous increase in endogenous levee of polyamines were found in ozone-exposed conidia. The inverse relationship between appressorium formation and level of polyamines implies that ozone-mediated increase in intracellular level of polyamines may inhibit appressorium formation in rice blast fungus. Furthermore, rice plants inoculated with ozone-fumigated conidia exhibited less severe disease development than those with unfumigated conidia. This result suggests that the anti-conidial consequence of acute ozone will eventually weaken the rice blasts potential for multiple infection cycle. This further suggests that consequently, rice blast can be transformed from an explosive disease to one that has limited epidemiological potential in the field.

• 생명과학회지
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• 제6권4호
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• pp.299-303
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• 1996

미국사시나무(Populus tremuloides)의 삽목개체에 오존이 엽록소함량의 변화에 미치는 영향을 조사하였다. 오존은 일일 6시간씩, 주 3일간 연속적으로 open-top chamber에서 fumigation 하였다. 오존처리는 괴사반점과 광범위한 chlorosis 등 잎 조직에 심각한 상해를 발생시켰다. 오존처리에 의한 엽록소의 분해는 완전히 성숙한 잎에서 현저하게 관찰되었으나 어린 잎에서는 분해가 거의 보이지 않았다. 오존처리에 대한 엽록소의 반응은 실험 전 기간에 걸쳐 모든 실험대상식물에 있어 일정한 양상을 보였다. 또한 clone 별로 오존 민감성에 따라 엽록소함량의 변화에 상당한 유전적 변이를 보였다.

• Environmental Engineering Research
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• 제12권2호
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• pp.72-80
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• 2007

Experiments were conducted to identify the emissions from the car air freshener and to identify the formation of ultra-fine particles and secondary gaseous compounds during the ozone-initiated oxidations with emitted VOCs. The identified primary constituents emitted from the car air freshener in this study were $\alpha$-pinene, $\beta$-pinene, $\rho$-cymene and limonene. Formation of ultra-fine particles (4.4-160 nm) was observed when ozone was injected into the chamber containing emitted monoterpenes from the air freshener. Particle number concentrations, particle mass concentrations, and surface concentrations were measured in time dependent experiments to describe the particle formation and growth within the chamber. The irritating secondary gaseous products formed during the ozone-initiated reactions include formaldehyde, acetaldehyde, acrolein, acetone, and propionaldehyde. Ozone concentration (50 and 100 ppb) and temperature (30 and $40^{\circ}C$) significantly affect the formation of particles and gaseous products during the ozone-initiated reactions. The results obtained in this study provided an insight on the potential exposure of particles and irritating secondary products formed during the ozone-initiated reaction to passengers in confined spaces.