• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.601-607
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• 2013

The purpose of this study was to identify the effects of ozone pollution on the one woody species and two indoor plants in controlled environment. Pinus densiflora, Spathiphyllum patinii and Epipremnum aureum seedlings were exposed in both control and ozone chambers to investigate photosynthetic rate, water use efficiency, antioxidative enzyme activities such as GR(Glutathione reductase) and APX(Ascorbate peroxidase) activity and leaf anatomical response. Ozone was fumigated 8 hours for a day with 30 ppb concentration for 50 days. Pinus densiflora seedlings showed no significant difference on photosynthetic rate, water use efficiency, antioxidant enzyme activity during ozone exposure. Ozone concentration (30 ppb in this study) is not high enough to generate ozone damage on Pinus densiflora species. In contrast, ozone generally altered photosynthetic rate, antioxidant enzyme (especially GR) activity and leaf anatomy in two indoor species (Spathiphyllum patinii and Epipremnum aureum) exposed in ozone chamber were significantly differ from those of control in every measurement. These data suggest that two indoor species(Spathiphyllum patinii and Epipremnum aureum) are more sensitive to ozone than Pinus densiflora.

• Environmental Analysis Health and Toxicology
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• v.24 no.2
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• pp.137-148
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• 2009

This study quantitatively investigated the emissions of indoor air pollutants associated with the utilization of air fresheners indoors, and evaluated individual exposure to five specified indoor air pollutants, which were chosen on the basis of selection criteria. An electrically-polished stainless steel chamber (50L) was employed to achieve this purpose. Test air fresheners were selected through three steps: first, on the basis of market sales; second, on the basis on a preliminary head-space study; and lastly, on the basis of emissions of toxic compounds (benzene, ethyl benzene, limonene, toluene, and xylene). The empirical mathematical model fitted well with the time-series concentrations in the environmental chamber (in most cases, determination coefficient, $R^2{\gtrsim}$0.9), thereby suggesting that the empirical model was suitable for testing emissions. The concentration equilibrium appeared 180 min after the introduction of sample air fresheners into the chamber. Both the chamber concentrations of emission rates or factors varied greatly according to air freshener type. It is noteworthy that although benzene, ethyl benzene, toluene, and xylene were emitted from all test air fresheners, their exposure levels were not significant enough to result in any significant health risk. However, certain type of air fresheners were observed to emit significant amount of limonene, which is potentially reactive with ozone to generate secondary pollutants with oxidants such as ozone, hydroxyl radicals, and nitrogen oxides. The exposure levels to limonene associated with the utilization of three air fresheners were estimated to be 13 to 175 times higher than that of other air fresheners. This information can help consumers to select low-pollutant-emitting air fresheners.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.70-70
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• 2022

• Journal of fish pathology
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• v.12 no.1
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• pp.32-41
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• 1999

Ozonization for rearing seawater in land-based culture system has recently been utilized for disinfection of pathogenic microorganisms and improvement of water quality. This study was conducted to examine the effects of total residual oxidants (TRO) in ozone-treated seawater on survival, blood parameters, osmolality and oxygen consumption, and gill tissue of the flounder. Paralichthys olivaceus. Experiments were carried out with the starved flounder of 12~19 cm in total length at $20^{\circ}C$. The 48-hr and 96-hr $LC_{50}$ for the flounder amounts to 26.4 ppb and 22.3 ppb, respectively. With increase of TRO concentration from 24 to 39 ppb, the values of hematocrit, hemoglobin concentration, red blood cell count and osmolality of the flounder with respect to exposure time were significantly elevated, however, the oxygen consumption rates decreased. In the case of the fish exposed to 13 ppb for 96 hrs, blood glucose increased with an elapse of exposure time, while survival rate was 100%. Death apparently resulted by massive destruction of gill lamellar epithelium, severe osmotic imbalance and the lack of oxygen uptake. The results of this experiment indicated that to protect aquaculture organisms, the ozone-treated seawater should not contain any residual oxidants, and that relatively long-term exposure to TRO of low concentration can impact on survival and physiological conditions of the flounder.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.2
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• pp.108-116
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• 2023

Recently, the concentration of fine dust causative substances (NOx, VOC, etc.) in the atmosphere has increased, resulting in high concentrations of tropospheric ozone (O3) and increased damage to crops. This study aimed to analyze the impact of high concentrations of ozone gas on the initial growth of rice plants and investigate the relationship between ozone damage resistance and anthocyanin biosynthesis. To achieve this, rice plants were exposed to elevated levels of ozone g as using an ozone chamber, and subsequent measurements were taken to assess changes in growth, the percentage of damaged leaves, and the anthocyanin content. The results revealed that varieties with a higher proportion of damaged leaves exhibited a relative increase in anthocyanin biosynthesis following ozone exposure. Notably, detrimental effects on growth, such as decreased biomass, were mitigated. Additionally, Anthocyanin biosynthesis genes in rice were listed by selecting homologous genes from Arabidopsis and Maize. The expression of OsF3H2, OsFLS1 and OsLDOX3 was induced during ozone treatment. This result is expected to contribute to the study of the protection mechanism of plants from ozone damage.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.1
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• pp.40-46
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• 2001

Ozone ($O_3$)-induced changes in chlorophyll content and specific activities of antioxidant enzymes, such as superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), dehydroascorbate reductase (DHAR) and glutathione reductase (GR) were investigated in two rice cultivars (Oryza sativa L.) grown under variable nutrient treatments. For this study, two rice cultivars of Ilpumbyeo (IL) and Keumobyeo#l (KM), which were known as resistant and susceptible to $O_3$, respectively, were exposed to $O_3$at 0.15ppm for 30 days and investigated with 10 days interval. The available nutrient regimes were varied by doubling the supply of nitrogen (N), phosphorus (P) and potassium (K) Within a basic fertilizer status (N, P, K; 15, 12, 12kg/l0a$^{-1}$ ). In both cultivars and at all nutrient status, chlorophyll content in $O_3$-treated plants decreased with prolonged treatment period, although higher N, P and K supply with $O_3$ treatment alleviated the decrease in chlorophyll content. The activities of almost all enzymes investigated for this study were decreased during initial stages of $O_3$- exposure except GPX which maintained higher activity throughout the exposure period than the non-treated plant. However, the antioxidant enzymes in $O_3$-treated plants showed almost the same or higher activities on 30 days after $O_3$ - exposure. The most significant changes in activities were observed in GR of the $O_3$-treated leaves. With the prolonged treatment period, the activity of GR at 30 days was increased by 3-8 times compared to those in 10 days. Most of the investigated enzymes showed very similar tendency to $O_3$ treatment in all fertilizer status. There was no observed evidence for enhanced detoxification of $O_3$-derived activated oxygen species in plants grown under higher fertilizer status compared with that in plants grown under basic fertilizer status. The increase in the activities of SOD, APX and GR in rice leaves by relatively long-term treatment with $O_3$ at low concentration is considered to indicate that the plant became adapted to the $O_3$ stress and the protection system increased its capacity to scavenge toxic oxygen species. Our results in two rice cultivars indicated that there was little difference in the activities of antioxidant enzymes between IL and KM, which were known as resistant and susceptible cultivar to $O_3$

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.3
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• pp.173-182
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• 2010

This study was conducted to investigate ozone sensitivity of physiological indicators and the difference in ozone tolerance of 8 families of Sophora japonica seedlings on the basis of the standardized physiological indicators. After ozone treatment, photosynthetic parameters, photosynthetic pigments and malondialdehyde (MDA) content, and antioxidative enzyme activities were analyzed from the leaves of S. japonica seedlings. Ozone tolerance indices among 8 families were calculated with the standardized physiological parameters. In addition, the reduction of carboxylation efficiency and apparent quantum yield were observed in the leaves of seven families, except for family No. 6 and 7, respectively. The apparent quantum yield varied from -27% to -61% of the control seedlings. Photosynthetic pigment content differed significantly among 8 families, but was not affected significantly by ozone treatment. Superoxide dismutase (SOD) activity increased from 7% to 64% after ozone exposure, and significant difference existed among 8 families. Ascorbate-peroxidase (APX) activity of 8 families increased by ozone treatment, and the activity of family No. 7 showed the highest increase (218%) in comparison to their respective control plants. On the basis of the standardized indices, family No. 6 showed the lowest tolerance by indicating higher reduction of both photosynthetic parameters and pigment content and lower increase of antioxidative enzyme activities. On the contrary, family No. 7 showed the highest tolerance as indicated by lower reduction of photosynthetic parameters, higher amounts of photosynthetic pigments, and higher enzyme activity.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.1
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• pp.6-10
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• 2003

This study was conducted to select the ozone tolerant individuals of Cornus controversa Hemsl., and to use malondialdehyde (MDA) content as an indicator of plant damage level for several oxidative stress levels. Seeds of C. controversa were collected at 9 provinces in Korea. One-year-old seedlings were grown in greenhouses and exposed to 100 pub ozone concentration for 8h day$^{-1}$ for 10 weeks. At the termination of ozone exposure, heights of seedlings were measured and MDA contents in the leaves were analyzed. Tolerant, intermediate, and sensitive individuals were selected using the standardized indices of height and MDA content. Height and MDA content of C. controversa exposed to ozone were significantly different among individuals and provinces. MDA content showed negative correlation (r=-0.531, p$\leq$ 0.001) with height growth performance. Height and MDA content of tolerant individuals presented significant differences from those of sensitive individuals. As a result, MDA content may be suitable for the evaluation of the damage level of plants by oxidative stress.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.167-177
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• 2014

New technologies for water purification are continuously emerging to address global water quality problems, and one such technology involves advanced hermetic water purification facilities made by concrete that utilize ozone treatment processes. Better knowledge about surface deterioration of epoxy coating exposed to ozone treatment is needed as a foundation for development of improved methods and materials in the future. This study utilized atomic force microscopy (AFM), nanoindentation methods, and existing indirect methods such as visual observation, changes in mass, surface observation and chrominance analysis, to evaluate epoxy water-resistance and anti-corrosiveness. This study considered six different epoxy formulations to assess typical degradation characteristics of epoxy surfaces with regard to water-resistance/anti-corrosiveness. AFM and nanoindentation techniques emerged as promising direct methods with potential to provide quantitative measures of surface quality that are improvements upon existing indirect methods. The experiments also confirmed that some of the epoxy-coatings were severely iMPacted by ozone exposure, and thus the results demonstrate that concern about such deterioration is justified.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.213-213
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• 2011

Gold catalysts supported on TiO2 have shown a unique catalytic behavior on CO oxidation, depending on surface effects. Particle size has an influence on the surface activity. To make monodisperse Au nanoparticles, organic capping ligands, such as alkylthiols, were used by a "greener" synthesis method [1,2] and Au nanoparticles were deposited on TiO2. However, organic capping ligands must be removed for high catalytic activities by the Au nanoparticles without changing the Au size [3]. We used UV ozone treatment to decompose thiol ligands. The samples have been characterized by X-ray photoelectron spectroscopy to examine the surface modification by UV ozone treatment. We show the size distribution of the gold nanoparticles by light scattering analysis and transmission electron microscopy. Au/TiO2 have been prepared using the wetness impregnation method. The catalytic performance of CO oxidation over Au supported on TiO2 under oxidizing reaction conditions (40 Torr CO and 100 Torr O2) were tested. The results show that the catalytic activity depends on particle size and the time of UV ozone exposure, which suggests the role of sulfur bonding in determining the catalytic activity of Au/TiO2 catalysts.