• Title/Summary/Keyword: Nitrogen monoxide

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Combustion Emission Gas Analysis and Health Hazard Assessment about P. densiflora and Q. variabilis Surface Fuel Beds (소나무, 굴참나무 낙엽의 연소 방출가스 분석 및 건강 위험성 평가)

  • Kim, Dong-Hyun;Kim, Eung-Sik;Lee, Myung-Bo
    • Fire Science and Engineering
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    • v.23 no.5
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    • pp.24-31
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    • 2009
  • Based on fallen leaves of major Korean conifer species 'Pinus densiflora' and major Korean broadleaved species 'Quercus variabilis', this study sought to identify combustion emission gas types and measure their concentration by means of FTIR (Fourier Transform Infrared) spectrometer. As a result, it was found that there were total 13 types of combustion gas detected from fallen leaves of Pinus densiflora and Quercus variabilis, such as carbon monoxide, carbon dioxide, acetic acid, butyl acetate, ethylene, methane, methanol, nitrogen dioxide, ammonia, hydrogen fluoride, sulfur dioxide and hydrogen bromide. Notably, nitrogen monoxide was additionally detected from fallen leaves of Quercus variabilis. It was found that the overall concentration of combustion gas emitted from the fallen leaves of Pinus densiflora was 4.5 times higher than that from fallen leaves of Quercus variabilis. Particularly, it was found that emission concentration of some combustion emission gas types like carbon monoxide, carbon dioxide and butyl acetate exceeded the upper limit of their time-weighted average (TWA, ppm), while the emission concentration of carbon monoxide and carbon dioxide exceeded their short-term exposure limit (STEL, ppm) for both species. Thus, it was found that carbon monoxide and carbon dioxide have higher hazard to health than other gas types, because these two gas types account for higher than 99% of overall gas emission due to combustion of surface fire starting from litter layer in forest.

The Effect of Air Impurities on the PEMFC Performances (공기에 포함된 불순물에 의한 PEMFC 운전 성능 변화)

  • Jang, Jong-Hyun;Kim, Yi-Young;Han, Jong-Hee;Lee, Sang-Yeop;Cho, Eun-Ae;Kim, Hyoung-Juhn;Lim, Tae-Hoon
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.526-529
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    • 2008
  • The effect of air impurities on PEMFC performances were studied using electrochemical analysis, such as OCV monitoring, polarization, constant current operation, and electrochemical impedance spectroscopy. The nitrogen dioxide in air lowered the operation voltage at 1 A/$cm^2$ by 160 mV (10 ppm) and 227 mV (100 ppm), while the carbon monoxide effect was relatively not significant (30 mV at 100 ppm). For both nitrogen dioxide and carbon monoxide, the performances were largely recovered when pure air was provided again. Further study for additional air impurities and simulated air are under progress to provide fundamental data for the design of fuel cell vehicles.

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Combustion Emission Gas Analysis & Hazard Assessment to the Litter Layer in Forest (임내 낙엽층의 연소 방출가스 분석 및 건강 위험성 평가)

  • Kim, Dong-Hyun;Lee, Myung-Bo
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2009.04a
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    • pp.358-364
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    • 2009
  • 본 연구에서는 우리나라 주요 침엽수종인 소나무(Pinus densiflora)와 활엽수종인 굴참나무(Quercus variabilis)의 낙엽에 대해 FTIR(Fourier Transform Infrared) 분광계를 이용하여 배출 연소가스 종류 및 농도를 측정하였다. 실험결과 소나무와 굴참나무 낙엽에서 Carbon monoxide, Carbon dioxide, Acetic acid, Butyl acetate, Ethylene, Methane, Methanol, Nitrogen dioxide, Ammonia, Hydrogen Fluoride, Sulfur dioxide, Hydrogen bromide 등 13개 연소가스가 검출되었고 굴참나무 낙엽에서는 Nitrogen monoxide가 추가로 검출되었다. 방출된 연소가스의 전체 농도는 소나무 낙엽이 굴참나무 낙엽에 비해 4.5배 많이 검출되었다. 특히, 시간가중평균가스농도(TWA : Time-weighted average, ppm) 기준을 초과하는 연소가스는 Carbon monoxide, Carbon dioxide, Butyl acetate가 검출되었고 단시간노출기준(STEL : Short Term Exposure Limit, ppm) 기준을 초과하는 연소가스는 Carbon monoxide, Carbon dioxide로 소나무 및 굴참나무 모두에서 나타났다. 이에 산불에서의 낙엽층 지표화 연소시 전체 가스 방출량의 99% 이상을 차지하고 있는 Carbon monoxide, Carbon dioxide의 건강 위험성이 높은 것으로 나타났다. 하지만, 검출된 다른 건강 위험성 가스의 경우에도 연소물질의 양이 증가할수록 연소가스의 농도가 높아져 건강안정성에 해가 있을 것으로 판단되며 또한 검출된 연소가스 중 나무의 주요구성 원소가 아닌 Bromide, Fluoride 화합물에 대해서는 토양으로부터의 오염 또는 분석과정에서의 노이즈로 인한 검출 등에 대한 보다 면밀한 검토가 필요할 것으로 판단된다.

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Operational Characteristics of a Carbon Monoxide Laser for Instrumentationand its Applications (레이저 계측용 일산화탄소 레이저의 동작 특성 및 그 응용)

  • 김용평;최종운;김규욱;원종욱
    • Proceedings of the Optical Society of Korea Conference
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    • 1990.07a
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    • pp.33-38
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    • 1990
  • The carbon monoxide laser is one of useful light sources for precision laser instrumentation because of tis high efficiency and wideband characteristics. In this presentation, the liquid nitrogen cooled cw CO laser which is developed in KSRI will be reviewed

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An Emission Characteristics of a Controlled Auto-Ignition Gasoline Engine According to Variation of the Injection Timing (분사시기의 변화에 따른 제어자발화 가솔린기관의 배기특성)

  • Kim, H.S.
    • Journal of Power System Engineering
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    • v.8 no.3
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    • pp.5-10
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    • 2004
  • This work deals with a controlled auto-ignition (CAI) single cylinder gasoline engine, focusing on the extension of operating conditions. In order to keep a homogeneous air-fuel mixing, the fuel injector is water-cooled by a specially designed coolant passage. Investigated are the engine emission characteristics under the wide range of operating conditions such as 40 in the air-fuel ratio, 1000 to 1800 rpm in the engine speed, $150\;to\;180^{\circ}C$ in the inlet-air temperature, and $80^{\circ}$ BTDC to $20^{\circ}$ ATDC in the injection timing. A controlled auto-ignition gasoline engine which has the ultra lean-burn with self-ignition of gasoline fuel can be achieved by heating inlet air. It can be achieved that the emission concentrations of carbon monoxide, hydrocarbons and nitrogen oxides had been significantly reduced by CAI combustion compared with conventional spark ignition engine.

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A Study on the Indoor Environment of school classrooms in Seoul area (서울지역 학교 교실의 실내환경 조사연구)

  • 최한영
    • Journal of environmental and Sanitary engineering
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    • v.18 no.2
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    • pp.67-74
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    • 2003
  • In 15 schools where were chosen each location (East, West, South, North, Central) of Seoul area, 9 items were measured such as thermo circumstance(temperature, relative humidity, air current, intensity of illumination) particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide being based on the school indoor environment standard. It was showed that indoor temperature, relative humidity and air movement were suitable in comparison with school indoor environment standard. Intensity of illumination was suitable in comparison with all schools, only exception 2 schools. In all investigated schools were adequate for carbon monoxide, sulfur dioxide and nitrogen dioxide, in which each indoor environment standard (10ppw, 0.25ppm/hr, 0.15ppm/hr), but in 5 schools the carbon dioxide were exceeded for standard limit 1,000ppm of Korea. Indoor concentration of dust(PM-10) induced from respiration dust the standard of Korea ($150{\mu}g/m^3$) at all schools.

An Emission Characteristics of a Controlled Auto-Ignition Gasoline Engine according to Variation of the Air-Fuel Ratio (공기연료비의 변화에 따른 제어자발화 가솔린기관의 배기 특성)

  • Kim, Hong-Wung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.3 no.2
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    • pp.79-85
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    • 2004
  • This work treats a controlled auto-ignition (CAI) single cylinder gasoline engine, focusing on the extension of operating conditions. Investigated are the engine emission characteristics under the wide range of operating conditions such as 32 to 63 in the air-fuel ratio, 1000 to 1800 rpm in the engine speed, and 150 to $180^{\circ}C$ in the inlet-air temperature. A controlled auto-ignition gasoline engine can be achieved the ultra lean-burn with self-ignition of gasoline fuel by heating inlet air. It can be achieved that the emission concentrations of carbon monoxide, hydrocarbons and nitrogen oxides had been significantly reduced by CAI combustion compared with conventional spark ignition engines.

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An Emission Characteristics of a Controlled Auto-Ignition Gasoline Engine (제어자발화 가솔린기관의 배기 특성)

  • Kim, H.S.
    • Journal of Power System Engineering
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    • v.13 no.3
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    • pp.5-10
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    • 2009
  • This work deals with a controlled auto-ignition (CAI) single cylinder gasoline engine, focusing on the extension of operating conditions. The fuel is injected indirectly into electrically heated inlet air flow. In order to keep a homogeneous air-fuel mixing, the fuel injector is cooled by the water of a specially designed coolant passage. The engine emission characteristics were investigated under the wide range of operating conditions such as 32 to 63 in the air-fuel ratio, 1000 to 1800 rpm in the engine speed, and 150 to $180^{\circ}C$ in the inlet air temperature. The ultra lean-burn can be achieved by the auto-ignition of gasoline fuel due to the heated inlet air in the compression ignition gasoline engine. It is confirmed that the emission concentrations of carbon monoxide, hydrocarbons and nitrogen oxide can be significantly reduced by CAI combustion compared with the combustion of a conventional spark ignition engine.

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Destruction of $SO_2$ and NO on the Carbon-bed by Microwave

  • Kim, Dong-Sik;Lee, Dong-Kyu
    • Carbon letters
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    • v.1 no.1
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    • pp.31-35
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    • 2000
  • [ $SO_2$ ]and NO gases that come from the flue gases of most of all industrial combustion processes are harmful to everything include person and industrial facilities. For the simplification of the environmental clean-up processes, we studied the decomposition process by microwave. The microwave can destroy molecules into elementary atoms and offers energy to the atoms to react with carbons. Since the microwave is not absorbed into quartz tube and metallic chamber, the air pollution gases can be removed with much lower energy than in the case of conventional methods. We studied the decomposition of $SO_2$ and NO gases on the carbon beds by microwave. In the microwave field, the gases can be decomposed to form other compounds, such as elementary sulfur, nitrogen, carbon monoxide and carbon dioxide. It was found that CO gas is formed at higher temperature than is $CO_2$ gas, so it needs to control the bed temperature depend on products that we want to get.

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Effects of Pilot Injection on Low Temperature Diesel Combustion (파일럿 분사가 저온 디젤 연소에 미치는 영향)

  • Han, Sang-Wook;Bae, Choong-Sik
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.3
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    • pp.141-147
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    • 2012
  • A direct injection diesel engine with large amount of exhaust gas recirculation was used to investigate low temperature diesel combustion. Pilot injection strategy was adopted in low temperature diesel combustion to reduce high carbon monoxide and hydrocarbon emissions. Combustion characteristics and exhaust emissions of low temperature diesel combustion under different pilot injection timings, pilot injection quantities and injection pressures were analyzed. Retarding pilot injection timing, increasing pilot injection quantity and higher injection pressure advanced main combustion timing and increased peak heat release rate of main combustion. As a result of these strategies, carbon monoxide and hydrocarbon emissions were reduced. Soot emission was slightly increased with retarded pilot injection timing while the effect of pilot injection on nitrogen oxides emission was negligible under low combustion temperature condition. Spatial distribution of fuel from the spray targeting visualization was also investigated to provide more insight into the reason for the reduction in carbon monoxide and hydrocarbon emissions.