• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.12
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• pp.591-596
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• 2006

we have been developed on the ultra high concentration ozone generator system which is the core technology in the realization of the semiconductor photoresist strip process using the ozone-vapor chemistry. The proposed ozone generator system has the structure of the surface discharge type which adopt the high purity ceramic dielectric tube. We investigate the performance of the proposed ozone generator system experimentally and the results show that the system has very high ozone concentration characteristics of $19.7[wt%/O_2]$ at the flow rate of $0.3[{\ell}/min]$ of each discharge cell. As a result of the silicon wafer photoresist strip test, we obtained the strip rate of about 400[nm/min] at the ozone concentration of $16[wt%/O_2]$ and flow rate of $8[{\ell}/min]$. So, we confirmed that it's possible to use the proposed high concentration ozone generator system for the ozone-vapor photoresist strip process in the semiconductor and FPD industry.

• KIEAE Journal
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• v.12 no.6
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• pp.93-98
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• 2012

The concerns on high ozone concentration phenomenon is significantly growing in Seoul metropolitan area including the industry complex area, like Shiwha Banwol area. The aims of this research is the analysis of relationship between high concentrations of $O_3$ and solar radiation parameters in atmosphere. The understanding of the effects of solar radiation intensity, humidity, high air temperature on ozone concentration in a day is very useful to provide a direction for reducing of the high ozone concentration to a local government or a metropolitan government. The correlation analysis between maximum ozone concentration and various meteorological parameters in 2009 - 2011 carried out using IBM's SPSS program. The results showed that the mean correlations coefficient (R) between daily Ozone maximum and solar radiation resulted R = 0.64 during 2011. May - September in 10 air pollution stations. In case of correlations between daily ozone maximum and relative humidity showed negative correlation R = -0.61. The correlation analysis with mean air temperature during 1-3 PM resulted R = 0.29. This low correlation coefficient could be corrected by using of categorized data of ozone concentration. The daily maximum ozone concentration is more dependent on peak solar radiation and high air temperature during 1-3 PM than its simple daily maximum values. The results of this research would be used to develop the high ozone alert system around Seoul metropolitan area. This correlation analysis could be partially integrated to prediction of ozone peak concentration in connection with other methods like classification and regression tree(CART).

• Korean Journal of Environmental Agriculture
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• v.6 no.1
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• pp.38-43
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• 1987

This study was carried out to investigate the effect of ozone gas on paddy rice at the different nutrition levels. Jinjubyeo variety of rice plant was exposed to 0.3 ppm ozone gas for 3 hours. It was cultivated at three different application levels, optimum, -50%, and +50% of optimum of nitrogen, phosphorus, and potassium, respectively. After ozone gas fumigation, percentage of damaged leaf, malondialdehyde contents, activity of peroxidase, and nutrient contents of rice plant were observed. The results obtained are as follows. 1) Percentage of damaged leaf was increased at the both additional 50% application of nitrogen and 50% reduction of potassium. 2) Malondialdehyde contents of leaves were increased with the ozone gas exposure. 3) Percentage of damaged leaf was increased at the lower level of $K_2O/N$ ratio in leaves. 4) Nitrogen, phosphorus, and potassium contents in rice leaves were decreased with the ozone gas exposure. 5) The peroxidase bands on gel in electrophoresis were changed by the ozone gas exposure.

• Journal of Environmental Science International
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• v.19 no.3
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• pp.269-279
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• 2010

The relative contributions of physical and chemical processes to the production of ozone ($O_3$) were evaluated based on an integrated process rate (IPR) analysis using the MM5/CMAQ in a downtown (i.e., Yangsan_U) and suburban area (i.e., Ungsang) on high ozone days during spring and summer in 2006 (28 April and 8 August 2006). The IPR includes a horizontal advection (HADV) and diffusion (HDIF), a vertical advection (ZADV) and diffusion (VDlF), a dry deposition (DDEP), and a chemistry (CHEM). The VDIF in Yangsan_U was found to be the most dominant contributor (29.5% in spring and 32.1% in summer) to high $O_3$ concentrations, followed by the HADV and ZADV. In contrast, the contributions of the HADV (40.3% in spring and 32.3% in summer) in Ungsang were significantly higher than those of VDIF and ZADV. Moreover, $O_3$ production due to the chemical effect in the two areas (especially in Ungsang) during summer was found to be moderately higher than that during spring.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.8
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• pp.311-315
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• 2016

The efficiency of manure treatment was investigated in terms of the pH, BOD, COD, SS, T-N and TP with a variation in the injection amount of PAC, polymer and ozone. The wastewater flow rate to the AOF is of $7.4m^3/hr$ with a reaction time of 30 minutes. The amount of PAC and polymer changed by 30, 35, 40 ml/min, and 30, 40, 50 ml/min, respectively. The amount of ozone injected varied from 110, 125, and $150kg-O_3/hr$. The optimum manure treatment performance was found for a PAC of 35 ml/min for the COD and SS, with polymer of 30 ml/min, and ozone injection of $150kg-O^3/hr$. A substantially optimum dose for each PAC, polymer, and ozone was also found to exist.

• Journal of the Korean Chemical Society
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• v.36 no.5
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• pp.644-651
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• 1992

The kinetics of the gas phase reaction of ozone(∼0.5 torr) with sulfur trioxide was investigated in the range of 6∼12 torr pressure at 69∼150${\circ}C$. The reaction rate of ozone with sulfur trioxide was faster than the reaction rate of $O_3 in the presence of CO_2 alone. No evidence for a molecular reaction of O_3 with SO_3 was found and the faster rate is probably due to impurity (HX) from the SO_3 reactant which gives rise to a chain reaction initiated by O_3 ＋ HX → OH ＋ O_2 ＋ X and also SO_3 has a larger collision diameter, which may be attributed to the O3 thermal decomposition more feasibly. The proposed experimental law [-d(O_3)/dt] = k_a(SO_3)(O_3) ＋ k_b(O_3)^{3/2} gives a rate constant ka(M-1 s-1) = (1.55 {\pm} 0.67) {\times} 105 e-{(9.27 0{\pm}0.43)kcal/RT}.$

• Journal of the East Asian Society of Dietary Life
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• v.11 no.3
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• pp.219-224
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• 2001

This study was conducted to investigate the optimal conditions for the growth of soybean sprouts by ozone water watering. Optimal conditions for ozone water watering of soybean sprouts during cultivation at 2$0^{\circ}C$ were evaluated with ozone concentration(0.1~O.5 ppm) and watering frequency(1~9 times) by response surface methodology. The optimal conditions for growth of soybean sprouts were ozone concentrations of 0.20~0.32 ppm, ozone treatment frequency of 3.0~4.4 times. Germination rates, hypocotyl weights and hypocotyl lengths in the soybean sprouts cultivated under the optimal conditions increased by 13.3, 10.1 and 11.9%, respectively, whereas root weights decreased by 89.0%.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.182-183
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• 2004

Atmospheric carbon monoxide (CO) and ozone $(O_3)$ play the important trace gases in tropospheric chemistry, through its concentration in the troposphere directly influences the concentrations of tropospheric hydroxyl (OH). Understanding the impact of CO and $O_3$ on the global tropospheric chemistry requires measurements of the global atmospheric CO and $O_3$ distributions. This study focuses on the identification of CO and O3 released in the East Asia between March 2000 and February 2004. During the period, the MOPITT instrument onboard the Earth Observing System (EOS)-Terra platform collected extensive measurement of CO. So we have used MOPITT data at 700hPa to analyze seasonal distribution of CO concentration. And the O3 measurements for this study were Total Ozone Mapping Spectrometer (TOMS) and Dobson spectrometer provided NASA/GSFC and Yonsei University, Korea. During springtime, the CO and O3 concentrations were increased over East Asia for April, May, and June. CO and O3 transport and chemistry in the springtime in East Asia are studied by use of the HYbrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model.

• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.297-311
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• 1997

To understand the mass-independent isotopic fractionation effects, thermal decomposition of ozone was performed. Initial oxygen gas was converted to ozone completely. Then, the ozone was decomposed to oxygen at various temperatures ($30~150^{\circ}C$). Isotopic compositions of product oxygen and residual ozone were measured using a stable isotope mass spectrometer. The experimental results were compared with the studies which were performed at the similar conditions. From the raw experimental data, the functions of the instantaneous fractionation factors were calculated by the least square fit. The results clearly showed the temperature dependence. They also showed the pressure dependence and the surface effect. This study may play an important role in the study of ozone decomposition mechanism. It can be applied to explain the mass-independent isotopic pattern found in stratospheric ozone and in meteorites.

• Textile Coloration and Finishing
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• v.5 no.4
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• pp.49-59
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• 1993

In order to study the bleaching of cotton fabrics, ozone which has been produced by an ozone generator, has been contacted with cotton fabrics in water at various conditions. The equipments used for the ozone treatment of cotton fabrics were the ozone generator and a liquor/ozone contactor. For the examination of the ozone bleaching effect on cotton fabrics the whiteness, tensile strength, wettability and clark softness of the ozone treated cotton fabrics were measured. The conclusion obtained were, ozone concentration was increased, as the voltage was increased and flow rate was decreased and oxygen amount was increased. Bleaching effect of treated fabrics increased with increasing attributed more the net concentration of ozone rather than the total ozone amount of produced. The whiteness of treated fabrics was found to be best when treating temperature was 15~20<$^{\circ}C$, in acidic condition. The tensile strength of treated fabrics decreased as the treating time increased, and as the temperature raised, and the acidity increased. The wicking distance of treated fabrics increased slightly with increasing the treating time and the temperature. Clark softness of treated fabrics was not changed until passing 30min. of the treating time, then it decreasing linealy with increasing the treating time.