• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.181-182
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• 2002

광화학스모그에 의한 오염이 심각하다고 알려진 서울의 경우 오존 1시간 환경기준 초과횟수는 '95년에 21회, '96년 174회, '98년 269회, 그리고 2000년에는 335회 등 매년 증가하고 있으며, 측정지점별 초과 횟수의 경우에도 완만한 증가추세를 보이고 있다. 2000년 말 현재 전국 53개 도시에 대기오염 자동측정 망이 약 152개소가 운영되고 있으나, 측정소의 절대적 개수를 계속하여 늘릴 수 없다는 한계와 시·공간적으로 변화하는 오존 전구물질(NOx, VOCs 등) 및 오존의 현황자료 부족으로 인하여 광화학 대기오염의 생성 규명을 파악하는데 어려움이 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.303-304
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• 2003

연안도시의 경우 해양 배경농도의 영향과 내륙과 비교해 강한 풍속조건이 형성됨으로 오존농도의 일변화 폭이 적으며 야간에 농도상승 현상이 빈번히 나타난다. 또한 일반적으로 여름철 주로 발생하는 해풍에 의해 고농도를 경험하게 되는데, 이는 해풍역전으로 인한 연직혼합의 억제와 (Lu and Turco, 1994) 해풍전선의 이동 (McElroy and Smith, 1991), 해풍의 내륙침투 시 생기는 Fumigation 효과(Entwistle, et al., 1997; Zhang et al., 1998) 등으로 설명되어 진다. 아울러 해륙풍순환으로 생기는 오전의 대기정체현상은 오후의 오존의 광화학 생성과 축적에 기여하게 되며 (Liu et al., 1994), 해풍 발달 시에는 오존 및 전구물질이 내륙 수송되어 풍하측 지역에 고농도가 나타나게 된다(Zhang et al., 1998). (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.96-97
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• 2003

최근 심화되고 있는 대도시 오존오염의 저감 실현시키기 위한 가장 중요한 과제로 오존의 생성과 관련 있는 전구물질(precursor)에 대한 제어과정이 대두되고 있다. 따라서 오존전구물질의 주요 배출원인 자동차배출 VOCs에 대해 정확한 총 배출량을 파악하고, VOCs의 각 성분별 배출구성비를 파악하는 것은 오존생성반응을 모사ㆍ예측하고 대기중 오존 오염을 제어하는데 있어서 필수적이라 하겠다. 그러나 국내에서는 자동차등 이동오염원에 대한 배출실태조사가 이루어지지 않아 배출원 관리에 어려움이 있는 실정이다. (중략)

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.3
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• pp.191-204
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• 2017

Concerns on the air pollution problem caused by ambient fine particles have become a big social issue in Korea. Important factors that should be addressed to develop effective and efficient air quality management policy, especially, against fine particles are discussed and research and policy directions to address these factors are suggested. It is suggested that two factors are in high priority; one is scientific understanding of the major formation mechanisms of fine particles and the other is the process of policy decision and implementation. For the scientific understanding, smog chamber measurement, intensive field study, and chemical transport model development that can simulate the characteristics of Northeast Asia are considered to be important. For the policy directions, priority setting of the proposed policies and development and implement of effective communication sytem are considered to be important.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.362-363
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• 2003

Photochemical ozone is formed from nitrogen oxides (NOx) and volatile organic compounds(VOCs) through non-linear interactions between chemical reactions and meteorology, and the relationship between precursors and photochemical ozone will be changed to match the emission distribution and meteorological fields. It is generally known that for some conditions the process of ozone formation is controlled almost entirely by NOx and is largely independent of VOC, while for other conditions ozone production increases with increasing VOC and does not increase(or sometimes even decreases) with increasing NOx (omitted)

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.3
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• pp.277-284
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• 2005

Catalytic oxidation of toluene in low concentrations was investigated over various supports. As the manganese oxides loading was increased, the conversion of toluene increased at a lower temperature. The 18.2 $wt\%$ $Mn/\gamma-Al_2O_3$ appeared to be the most active catalyst. Among the supports, $\gamma-Al_2O_3$ was more active than $TiO_2$ and $SiO_2$. Manganese oxide catalysts prepared from manganese nitrate precursor were better for complete oxidation of toluene than those prepared from manganese sulfate and chloride precursor because sulfate from manganese sulfate and chloride from chloride manganese remained even after the calcination by XRD (X-Ray Diffraction) analyses.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.241-242
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• 2002

오늘날 전 세계적으로 대도시 지역에서 지표면 오존농도가 환경기준을 초과하는 빈도가 증가함에 따라 오존의 생성과 관련 있는 전구물질(precursor)인 질소산화물과 휘발성유기화합물에 대한 제어과정이 지표면 오존농도의 저감을 실현하기 위하여 가장 중요한 과제로 대두하고 있다1). 이러한 오존농도의 증가 원인 파악을 위하여 환경부는 서울을 중심으로 한 수도권지역 뿐만 아니라 전국의 대도시의 주변지역에 대한 광화학 측정망을 확충하고 고농도 오존 발생기간에 대하여 집중측정 등을 수행하며, 대책수립에 필요한 기초자료를 마련할 수 있도록 하는 방안을 모색하고 있다. (중략)

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.34 no.3
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• pp.103-107
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• 2024

In this study, nickel, a pure metal material, was proposed as a saggar for synthesizing NCM [Li(Ni_xCo_yMn_z)O₂] cathode active material. Nickel is known as a metal that is resistant to oxidation and has a high melting point. Nickel is one of the main components of NCM cathode material and was expected to be free from problems with contamination from saggar during cathode material synthesis. We sought to confirm the possibility of nickel as a saggar for synthesizing NCM cathode active materials. When a Ni metal crucible and Ni_0.8Co_0.1Mn_0.1(OH)₂ (NCM 811) precursor material were reacted at 900℃ for a long time, the change in the reaction layer on the surface of the crucible over time was analyzed. The nickel crucible reaction layer formed during heat treatment at 900℃ was nickel oxide, and is thought to have been created by simultaneous oxygen diffusion from the cathode precursor oxide and reaction with oxygen in the atmosphere. The change in thickness of the oxide layer appears to slow down after 480 hours, which suggests that the rate of oxygen diffusion from the precursor is reduced. It remained combined without falling out of the crucible until 480 hours. However, it was confirmed that the oxide layer falls off after 720 hours, so it is thought that it can be used as saggar for NCM synthesis only for a certain period of time.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.179-185
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• 2000

In this study, we examined the movement of chlorophenol as a precursor of the dioxin in the after-combustion to minimize the creation and emission of dioxin in a municipal waste incinerator. The CPs was injected to the electric incinerator in temperature $300{\sim}500^{\circ}C$, using $N_2$ gas to control the reaction time, The oxygen quantity supplied into the $CP_s's$ isomer combustion was added with the value of experience formula. When the space velocity in reactor was 60~80/sec, the removal efficiency of CP was obtained in the presence of Mo-V catalyst and non catalyst. The efficiency in non-catalyst was 74% to 80% mono-CP, di-CP 55~66%, tri-CP 50~58%, while mono-CP 90~99.9%, di-CP 96~97%, tri-CP 76~99% in a catalyst. Consequently, it was shown that these were 20~30% more efficienct than those.

• Journal of the Korean Applied Science and Technology
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• v.36 no.3
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• pp.905-914
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• 2019

In this study, The PMF model was used to identify pollutant sources and their contribution to pollution sources of $PM_{2.5}$. The contribution of A city to each source was 19.8% for Secondary Sulfate, followed by Mobile 19.5%, Industry 16.0%, Biomass Buring 14.1%, Secondary Nitrate 14.1%, Oil Combustion 11.6%, Aged Sea Salt 2.6%, Soil 2.5% and so on. Sulfate and Ammonium concentrations were the highest contributing sources in the source profile, which was analyzed to be Secondary Aerosols produced by Photochemical Reactions of gaseous precursors (SOx and ammonia gas) in the atmosphere.