• 조명전기설비학회논문지
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• 제28권5호
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• pp.76-81
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• 2014

The ozone generation is commonly made with silent discharge method using quartz glass dielectric. In this paper, using $Al_2O_3$ dielectric to instead of the traditional quartz glass dielectric to improve the system efficiency is presented. The dielectric was manufactured as tube shape (Internal diameter${\times}$ Outside diameter: $11{\times}15mm$) using 99% $Al_2O_3$ ceramic. The characteristics of dielectric discharge and ozone generation were studied of experiments with variation of discharge power, discharge electrode space and rate of flow for supplied gas ($O_2$/Air). As the experimental results, in the same discharge space, the ozone concentration continuously increased with input power increasing, and ozone yield increased until saturation happened. Also, the expended power increased with discharge space extended due to discharge power increased. In additional, the ozone concentration of oxygen ozone was higher than air that was observed when using oxygen ozone in proposed experiments.

• 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.

• 조명전기설비학회논문지
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• 제15권5호
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• pp.46-54
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• 2001

본 연구에서는 공업용으로 널리 사용되고 있는 오존발생법의 하나인 무성방전법을 응용한 고주파 전원인가에 의한 오존발생기를 설계·제작하여 오존생성의 중요한 인자중 하나인 원료가스의 온도변화에 따른 오존생성특성을 연구하였다. 또한, 원료가스의 온도의 변화에 따른 오존생성농도, 오존생성수율 및 오존발생량 상승효과에 관한 연구를 수행하였다.

• 한국지구과학회지
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• 제23권5호
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• pp.424-435
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• 2002

이 연구에서는 1997년부터 1999년 3년 간 대구광역시의 시간별 O$_3$ 농도 자료와 기상자료를 분석하여, 대구시의 고농도 오존 발생 일에 나타나는 기상학적 특성을 알아보고자 한다. 고농도 오존 발생 일의 선정은 우리나라 환경기준치인 1시간 평균 오존 농도 100ppb를 초과한 지점이 대구시의 6개 측정 지점 중 한 지점이라도 있는 경우로 정했다. 고농도 오존 발생 일은 13일이었으며, 5월과 9월이 가장 그 빈도가 높았다. 고농도 오존 발생 일의 하루 평균 최대 오존 농도는 81.6ppb이었으며, 8시간 평균 농도는 58.6ppb이었다. 이는 대구의 오존 오염이 연속적으로 그리고 광범위하게 일어났고 있음을 의미한다. 하루 최고 오존 농도는 일사량, 최고 온도와 양의 상관을 보였으며, 상대 습도, 풍속, 구름양과는 음의 상관을 보였다. 일사량과의 상관계수가 0.45로 가장 높았다. 고농도 오존 발생 일의 기상 값과 그 날을 포함하는 월평균 값과의 차이를 보면, +1.58hPa(해면 기압), +3.45${\circ}$C(최고 기온), -5.69%(상대 습도), -0.46ms$^{-1}$(풍속), -1.79(구름양), +3.97MJm$^{-2}$(일사량)을 각각 보였다. 이는 0700${\sim}$1100LST사이의 높은 일사량, 낮은 풍속, 무강수가 고농도 예측의 중요특징임을 나타낸다. 이는 이 시간의 정체와도 연관이 있다.

• 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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1759-1761
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• 2001

In this paper, a co-axial cylinder type ozonizer using silent discharge known as an ozone generation was designed and fabricated. A cooling system was installed to investigate the characteristics of ozone generation in accordance with temperature change of the supplied gas known as an important factor. The characteristics of ozone generation were investigated in accordance with the existence of cooling system and the change of cooling temperature.

• Journal of Astronomy and Space Sciences
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• 제15권1호
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• pp.119-138
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• 1998

최근에 인공위성에 의한 대기 중의 미량 기체 관측이 활발하다. 따라서 이들 자료의 처리기법 개발이 매우 중요하다. 그러므로 이 연구에서는 인공위성에 의해 태양 엄폐범(太陽 掩蔽法: Solar Occultation Method)으로 관측한 대기 주연 경로(周緣 經路: limb path)의 접선 고도별 평균 투과율로부터 연직 오존 분포를 도출하고, 온도와 기압 오차의 민감도 오차의 민감도 실험을 하고자 한다. 여기에서 서울의 반전(Umkehr)관측에 의하여 구한 연평균 연직 오존분포로 계산된 평균 투과율을 인공위성으로부터 관측된 평균 투과율로 가정하였다. HALOE SIDS (Hallogen Occultation Experiment Simulated Instrument Data Set)의 연직 오존 자료를 초기치로 하고 온도와 기압의 연직 분포를 입력값으로 하여 대기 평균 투과율을 파장 $9.89{\mu}m$와 $10.02{\mu}m$ 사이에서 접선고도별로 계산했다. 관측 평균 투과율에 대하여 계산한 평균 투과율로부터 오존 분포 법으로 접선고도 10km에서 50km까지 매 3km마다 오존 농도를 도출하였다. 도출된 서울의 연직 오존 분포를 관측한 연직 오존 분포와 비교하였다. 이 결과에 의하면 전 고도에 걸쳐서 서울의 연직 오존 분포가 오차가 거의 없을 정도로 정확하게 도출되었다. 그리고 민감도 실험을 위하여 관측 평균 투과율에$\pm0.001$, 각 층의 온도에 $\pm3K$, 그리고 각 층에 기압의 $\pm3\%$의 강제 오차를 각각 주었다. 이들 각 오차는 ADEOS/ILAS 관측 오차에 근거하였다. 이들의 결과는 투과율 오차에 대하여 -6.5%에서 +6.9%, 온도 오차에 대하여 -9.5%에서 +10.5, 그리고 기압 오차에 대하여 -5.1%에서 +5.4%의 고도별 오존 량 오차가 각각 나타났다. 태양 엄폐 법에 의해 비교적 정확한 연직 오존 분포를 도출할 수 있었다. 이 도출 과정에서 특히 온도 관측이 중요함을 알 수 있었다.

• 한국전기전자재료학회논문지
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• 제31권5호
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• pp.341-344
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• 2018

In order to achieve a high efficiency for the silicon solar cell, a passivation characteristic that minimizes the electrical loss at a silicon interface is required. In this paper, we evaluated the applicability of the oxide film formed by ozone for the tunnel silicon oxide film. To this end, we fabricated the silicon oxide film by changing the condition of ozone oxidation and compared the characteristics with the oxide film formed by the existing nitric acid solution. The ozone oxidation was formed in the temperature range of $300{\sim}500^{\circ}C$ at an ozone concentration of 17.5 wt%, and the passivation characteristics were compared. Compared to the silicon oxide film formed by nitric acid oxidation, implied open circuit voltage (iVoc) was improved by ~20 mV in the ozone oxidation and the ozone oxidation after the nitric acid pretreatment was improved by ~30 mV.

• 한국환경과학회지
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• 제19권12호
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• pp.1431-1445
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• 2010

In order to clarify the impact of regional warming on the meteorological field and air quality over southeastern part of Korean Peninsula, several numerical experiment were carried out. Numerical models used in this study are WRF for the estimate the meteorological elements and CMAQ for assessment of ozone concentration. According to the global warming impact, initial air temperature were changed and its warming rate reach at 2 degree which was based on the global warming scenarios provided by IPCC. The experiments considering the global warming at initial stage were presented as case T_UP. Air temperature over inland area during night time for case T_UP is higher than that for Base case. During time since the higher temperature over inland area is maintained during daytime more intensified sea breeze should be induced and also decrease the air temperature in vicinity of coast area. In case of T_UP, high level concentrations ozone distribution area was narrowed and their disappearance were faster after 1800LST. As a results, wind and temperature fields due to the global warming at initial stage mainly results in the pattern of ozone concentration and its temporal variation at South-Eastern Part of the Korean Peninsula.

• 한국환경과학회지
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• 제10권6호
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• pp.417-422
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• 2001

The vertical structure of atmosphere was observed In investigate the variation of surface ozone concentration by vertical downward mixing of residual ozone in the atmospheric boundary layer at the Busan coastal area. Airsonde and pilot balloon measurements were made at Gamcheondong and the Kimhae airport for April 26~27, 1996. The vertical potential of potential temperature showed a residual layer between 510m and 1800m from 2100LST April 26 to 0900LST April 27. The downward mixing of ozone in the residual layer of the atmospheric boundary layer was confirmed from vertical profile of mixing ratio near 600m in the morning. The thickness of the sea breeze layer was 900m at 1500LST April 26. Thereafter, it become to be lowered with time A low level jet was measured near 900m at 0300LST on April 27 from a pibal measurement. Early morning sharp increase of surface ozone concentration at the Busan coastal area was caused by vertical downward mixing of ozone concentration rather than by photochemical reaction In the atmospheric boundary layer.