• Title/Summary/Keyword: Nitrogen monoxide

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Spatial-temporal Assessment and Mapping of the Air Quality and Noise Pollution in a Sub-area Local Environment inside the Center of a Latin American Megacity: Universidad Nacional de Colombia - Bogotá Campus

  • Fredy Alejandro, Guevara Luna;Marco Andres, Guevara Luna;Nestor Yezid, Rojas Roa
    • Asian Journal of Atmospheric Environment
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    • v.12 no.3
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    • pp.232-243
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    • 2018
  • The construction, development and maintenance of an economically, environmentally and socially sustainable campus involves the integration of measuring tools and technical information that invites and encourages the community to know the actual state to generate positive actions for reducing the negative impacts over the local environment. At the Universidad Nacional de Colombia - Campus $Bogot{\acute{a}}$, a public area with daily traffic of more than 25000 people, the Environmental Management Bureau has committed with the monitoring of the noise pollution and air quality, as support to the campaigns aiming to reduce the pollutant emissions associated to the student's activities and campus operation. The target of this study is based in the implementation of mobile air quality and sonometry monitoring equipment, the mapping of the actual air quality and noise pollution inside the university campus as a novel methodology for a sub-area inside a megacity. This results and mapping are proposed as planning tool for the institution administrative sections. A mobile Kunak$^{(R)}$ Air & OPC air monitoring station with the capability to measure particulate matter $PM_{10}$, $PM_{2.5}$, Ozone ($O_3$), Sulfur Oxide ($SO_2$), Carbon Monoxide (CO) and Nitrogen Oxide ($NO_2$) as well as Temperature, Relative Humidity and Latitude and Longitude coordinates for the data georeferenciation; and a sonometer Cirrus$^{(R)}$ 162B Class 2 were used to perform the measurements. The measurements took place in conditions of academic activity and without it, with the aim of identify the impacts generated by the campus operation. Using the free code geographical information software QGIS$^{(R)}$ 2.18, the maps of each variable measured were developed, and the impacts generated by the operation of the campus were identified qualitative and quantitively. For the measured variables, an increase of around 21% for the $L_{Aeq}$ noise level and around 80% to 90% for air pollution were detected during the operation period.

Selective Catalytic Reduction of NO by H2 over Pt-MnOx/ZrO2-SiO2 Catalyst (Pt-MnOx/ZrO2-SiO2 촉매에서 수소에 의한 일산화질소의 선택적 촉매 환원반응)

  • Kim, Juyoung;Ha, Kwang;Seo, Gon
    • Korean Chemical Engineering Research
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    • v.52 no.4
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    • pp.443-450
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    • 2014
  • Selective catalytic reduction of nitrogen monoxide by hydrogen ($H_2$-SCR of NO) over platinum catalysts impregnated on zirconia-incorporated silica ($ZrO_2-SiO_2$) and manganese oxide ($MnO_x$) was investigated. $Pt-MnO_x$ catalyst showed low conversions and low yields of $N_2O$ and $NO_2$ at $100{\sim}350^{\circ}C$. On the other hand, NO conversions over $Pt/ZrO_2-SiO_2$ were very high, but $N_2O$ was predominantly produced at $100-150^{\circ}C$ and the yield of $NO_2$ increased with temperature at $200-300^{\circ}C$, resulting in poor $N_2$ yields. $Pt-MnO_x/ZrO_2-SiO_2$ exhibited a small enhancement in $N_2$ yield at $100-150^{\circ}C$ due to the synergy of $MnO_x$ and $ZrO_2-SiO_2$. The surface composition and oxidation state of the catalyst components and the acidity of the catalysts were examined. IR spectra of the adsorption of NO and their subsequent reactions with hydrogen on these catalysts were also recorded. The variations of conversion and product yield according to the catalyst components in the $H_2$-SCR of NO were discussed in relation to their catalytic roles.

An Study on Estimating Cargo Handling Equipment Emission in the Port of Incheon (인천항 하역장비 대기오염물질 배출량 산정 연구)

  • Zhao, Ting-Ting;Pham, Thai-Hoang;Lee, Hyang-Sook
    • Journal of Korea Port Economic Association
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    • v.36 no.3
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    • pp.21-38
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    • 2020
  • Currently, in-port emissions are a serious problem in port cities. However, emissions, especially non-greenhouse gases, from the operation of cargo handling equipment (CHE) have received significant attention from scientific circles. This study estimates the amount of emissions from on-land port diesel-powered CHE in the Port of Incheon. With real-time activity data provided by handling equipment operating companies, this research applies an activity-based approach to capture an up-to-date and reliable diesel-powered CHE emissions inventory during 2017. As a result, 105.6 tons of carbon monoxide (CO), 243.2 tons of nitrogen oxide (NOx), 0.005 tons of sulfur oxide (Sox), 22.8 tons of particulate matter (PM), 26.0 tons of volatile organic compounds (VOCs), and 0.2 tons of ammonia (NH3) were released from the landside CHE operation. CO and NOx emissions are the two primary air pollutants from the CHE operation in the Port of Incheon, contributing 87.71% of the total amount of emissions. Cranes, forklifts, tractors, and loaders are the four major sources of pollution in the Port of Incheon, contributing 84.79% of the total in-port CHE emissions. Backward diesel-powered machines equipped in these CHE are identified as a key cause of pollution. Therefore, this estimation emphasizes the significant contribution of diesel CHE to port air pollution and suggests the following green policies should be applied: (1) replacement of old diesel powered CHE by new liquefied natural gas and electric equipment; (2) the use of NOx reduction after-treatment technologies, such as selective catalytic reduction in local ports. In addition, a systematic official national emission inventory preparation method and consecutive annual in-port CHE emission inventories are recommended to compare and evaluate the effectiveness of green policies conducted in the future.

Molecular Structure of PCP Pincer Complexes: Poisoning Catalyst on the Dehydrogenation of Alkanes (알칸의 탈수소화반응에서의 촉매독 화합물의 분자구조)

  • Lee Ji Hyun;Chun Sang Jin;Kwon Ki Hyeok;Lee Do Weon
    • Korean Journal of Crystallography
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    • v.16 no.1
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    • pp.43-53
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    • 2005
  • The dihydrido P-C-P pincer complex, $IrH_2{C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (1), was successfully prepared from the reaction of the hydrochloride complex, $IrClH (C_6H_3-2,6-(CH_2PBu_2^t)_2}$, and super acid $(LiBEt_3H)$ under 1 atm of hydrogen in pentane solution at room temperature and followed by Heating at $130^{\circ}C$ in vacuo. Jensen recently found that the dihydrido P-C-P pincer complex 1 is a highly active homogeneous catalyst for the transfer dehydrogenation of alkanes with unusual longterm stability at temperatures as high as $200^{\circ}C$. The treatment of dihydrido complex 1 with nitrogen, water, carbon dioxide, and carbon monoxide in presence of tert-butylethylene (the) at room temperature in an appropriate solution gave the dinitrogen complex, $[Ir{C-6H_3-2,6-(CH_2PBu_2^t)_2}]_2({\mu}-N_2)$ (2), the hydrido hydroxyl complex, $IrH(OH){C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (3), the carbon dioxide complex, $Ir({\eta}^2-CO_2) {C_6H_3-2,6-(CH_2PBu_2^t)_2}$ (including the bicarbonate complex, $IrH({\kappa}^2-O_2COH){C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(4))$, and the carbonyl complex, $Ir(CO) {C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(5)$ (including the carboxyl complex, $IrH(C(O)OH) {C_6H_3-2,6-(CH_2PBu_2^t)_2}\;(6))$, in good yield, respectively. These P-C-P iridium complexes were isolated and characterized by $^1H,\;^{13}C,\;^{31}P\; NMR$, and IR spectroscopy. In addition, the complexes (1-6) were characterized by a single crystal X-ray crystallography. These complexes account for these small molecules' inhibition of dehydrogenation of alkanes catalyzed by the dihydrido complex 1.

A Meta-Analysis of Air Pollution in Relation to Daily Mortality in Seven Major Cities of Korea, 1998-2001 (메타분석을 적용한 전국 7개 대도시의 대기오염과 일일사망발생의 상관성 연구(1998년$\sim$2001년))

  • Cho, Yong-Sung;Lee, Jong-Tae;Son, Ji-Young;Kim, Yoon-Shin
    • Journal of Environmental Health Sciences
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    • v.32 no.4 s.91
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    • pp.304-315
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    • 2006
  • This study is performed to reexamine the association between ambient air pollution and daily mortality in seven major cities of Korea using a method of meta-analysis with the data filed for the period 1998-2001. These cities account for half of the Korean population (about 23 million). The observed concentrations of carbon monoxide (CO, mean=1.08 ppm), ozone ($O_3$, mean=33.97 ppb), particulate matter less than 10 ${\mu}m$ ($PM_{10},\;mean=57.11\;{\mu}g/m^3$), nitrogen dioxide ($NO_2$, mean=25.09 ppb), and sulfur dioxide ($SO_2$, mean=9.14 ppb) during the study period were at levels below Korea's current ambient air quality standards. Generalized additive models were applied to allow for the highly flexible fitting of seasonal and long-term time trends in air pollution as well as nonlinear associations with weather variables, such as air temperature and relative humidity. Also, we calculated a weighted mean as a meta-analysis summary of the estimates and its standard error. In city-specific analyses, an increase of $41.17{\mu}g/m^3(IQR)\;of\;PM_{10}$ corresponded to $1{\sim}12%$ more deaths, given constant weather conditions. Like most of air pollution epidemiologic studies, this meta-analysis cannot avoid fleeing from measurement misclassification since no personal measurement was taken. However, we can expect that a measurement bias be reduced in district-specific estimate since a monitoring station is better representative of air quality of the matched district. Significant heterogeneity was found for the effect of all pollutants. The estimated relative risks from meta-like analysis increased compared to those relative risks from pooled analysis. The similar results to those from the previous studies indicated existence of health effect of air pollution at current levels in many industrialized countries, including Korea.

Oxidation and Removal of NO Emission from Ship Using Hydrogen Peroxide Photolysis (과산화수소 광분해를 이용한 선박 배가스 내 NO 산화흡수에 관한 연구)

  • Lee, Jae-Hwa;Kim, Bong-Jun;Jeon, Soo-Bin;Cho, Joon-Hyung;Kang, Min-Kyoung;Oh, Kwang-Joong
    • Clean Technology
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    • v.23 no.3
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    • pp.294-301
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    • 2017
  • Air pollution associated with the $NO_x$ emission from the ship engines is becoming one of the major environmental concerns these days. As the regulations on ship pollutants are strengthened, the wet absorption method, for controlling complex pollutants in a confined space, has the advantage of simultaneously removing various pollutants, but the low solubility of nitrogen monoxide is drawback. In this study, for improving existing denitrification scrubber system, NO oxidation process by hydroxyl radical produced from irradiating UV light on $H_2O_2$ is suggested and the $H_2O_2$ decomposition rates and hydroxyl radical quantum yields were measured to find the optimum condition of $H_2O_2$ photolysis reaction. As a result, the optimum quantum yield and photolysis rate of $H_2O_2$ were 0.8798, $0.6mol\;h^{-1}$ at 8 W, 2 M condition, and oxidation efficiency of 1000 ppm NO gas was 40%. In batch system, NO removal efficiency has a range of 65.0 ~ 67.3% according to input gas concentration of 100 ~ 1500 ppm. This results indicate that the scrubber system using hydrogen peroxide photolysis can be applied as air pollution prevention facility of ship engines.

A Study on Combustion Characteristics in terms of the Type of Fuel Supply Device (Feeder) of a Wood Pellet Boiler (목재펠릿보일러의 연료공급 장치의 형태에 따른 연소특성에 관한 연구)

  • Choi, Yun Sung;Euh, Seung Hee;Oh, Kwang Cheol;Kim, Dae Hyun;Oh, Jae Heun
    • Journal of Energy Engineering
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    • v.24 no.2
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    • pp.120-128
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    • 2015
  • This study reports the combustion characteristics, such as burner temperature and the concentration of exhausted gas ($O_2$, $CO_x$, $NO_x$) due to the different types and pitches of the fuel supply feeder of the wood pellet boiler. The 1st grade wood pellets composed of mainly larch have been used for the experiment. In case of using the spring feeder, mean temperature of burner was approximately $821.76^{\circ}C$, and the mean concentration of oxygen, carbon monoxide, carbon dioxide and nitrogen oxide were approximately 8.88%, 93.35ppm, 12.15% and 139.83 ppm, respectively. The test result with the spring feeder was shown to approach the condition of complete combustion compared to that of a screw feeder and were in good agreement with authentication judgement standard. Furthermore, the combustion efficiency was improved according to the growth of screw pitch. The control of air flow rate from the blower and ventilator is needed to achieve the complete combustion.

A Study for Developing an Operating Mode-Based Emission Model for Korea (한국형 운행 모드 기반 배출량 산정 모형 개발에 관한 연구)

  • HU, Hyejung;FREY, Christopher;YOON, Chunjoo;YANG, Choongheon;KIM, Jinkook
    • Journal of Korean Society of Transportation
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    • v.34 no.2
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    • pp.180-190
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    • 2016
  • Atmospheric pollutants such as Nitrogen Oxides(NOx), Carbon Monoxide(CO), Carbon Dioxide($CO_2$), Particulate Matter(PM) and Hydrocarbons(HC) come from vehicle exhaust gases. Emission curves based on average travel speeds have been employed for estimating on-road emissions as well as evaluating environmental impacts of transportation plans and policies in Korea. Recently, there is a growing interest in estimation methods of vehicle emissions considering relationship between vehicle dynamic driving characteristics and emissions, and incorporating such emission estimators into traffic simulation models. MOVES Lite, a simplified version of MOVES, is one of the estimation methods. In this study, the authors performed a study to develop an adaptable version of MOVES Lite for Korea, called MOVES Lite-K. Vehicle types, driving characteristics, emission rates, and emission standards of Korea were reflected in MOVES Lite-K. The characteristics of emission calculation of MOVES Lite-K and NIER emission curves were compared and the adaptability of MOVES Lite-K were examined.

Concentrations of Criteria Pollutants in Indoor and Ambient Air of Public Facilities in Taegu Area (대구지역 공중이용시설의 실내 $\cdot$ 외 공기 중 기준성오염물질의 농도)

  • 송희봉;민경섭;한개희;김종우;백성옥
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.4
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    • pp.429-439
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    • 1996
  • A comprehensive air quality monitoring was carried out in this study to investigate the concentrations of criteria air pollutants in indoor and outdoor air of public facilities in Taegu area. Four different kinds of public facilities were seleced as sampling sites, which are underground stores, stations & terminals, general hospitals, and department stores. Each group of the public facilities was consisted of three different sampling sites. As a consequence, a total of 12 different sampling sites were surveyed throughout this study. Sampling was conducted simultaneously indoors, three times per day (in the morning, afternoon, and evening) and four times per year (spring, summer, fall, and winter) at each sampling site during the period of October 1994 to July 1995. A range of criteria pollutants were measured in order to obtain a broad profile of indoor and ambient air quality, including total suspended particles (TSP), carbon monoxide (CO), carbon dioxide ($CO_2$), formaldehyde (HCHO), sulfur dioxide ($SO_2$), and nitrogen dioxide ($NO_2$). In addition, temperature, relative humidity, and air current were measured on site together with those air pollutants. Results of this study indicated that the indoor levels of TSP, CO, $SO_2, and NO_2$ appeared to be generally higher in stations/terminals and underground stores than those in department stores and hospitals. However, HCHO and $CO_2$ were found to have higher levels in the department stores and hospitals than other places, indicating that the effects of indoor sources for these pollutants are significantly different from other combustion related pollutants such as TSP, CO, and $SO_2$. It was also found that there are marked seasonal and daily variations both in indoor and outdoor air quality. In general, combustion related pollutants such as CO, $SO_2$ and $NO_2$ showed a typical pattern of higher levels in winter than insummer, and also higher in the morning and/or in the evening than in the afternoon. However, the seasonal and daily patterns of HCHO appeared to be opposite to the combustion related pollutants, i.e., higher both in summer and in the afternoon, implying the effect of temperature on the volatilization from indoor sources of HCHO. Results of correlation analyses between indoor and outdoor air quality also indicated that the effects of outdoor sources on the indoor levels of TSP, $SO_2$, CO, and $NO_2$ and much significant, whilst no significant correlations between indoor and outdoor levels were found for HCHO and $CO_2$.

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Analysis of statistical models on temperature at the Suwon city in Korea (수원시 기온의 통계적 모형 연구)

  • Lee, Hoonja
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.6
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    • pp.1409-1416
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    • 2015
  • The change of temperature influences on the various aspect, especially human health, plant and animal's growth, economics, industry, and culture of the country. In this article, the autoregressive error (ARE) model has been considered for analyzing the monthly temperature data at the Suwon monitoring site in Korea. In the ARE model, five meteorological variables, four greenhouse gas variables and five pollution variables are used as the explanatory variables for the temperature data set. The five meteorological variables are wind speed, rainfall, radiation, amount of cloud, and relative humidity. The four greenhouse gas variables are carbon dioxide ($CO_2$), methane ($CH_4$), nitrous oxide ($N_2O$), and chlorofluorocarbon ($CFC_{11}$). And the five air pollution explanatory variables are particulate matter ($PM_{10}$), sulfur dioxide ($SO_2$), nitrogen dioxide ($NO_2$), ozone ($O_3$), and carbon monoxide (CO). Among five meteorological variables, radiation, amount of cloud, and wind speed are more influence on the temperature. The radiation influences during spring, summer and fall, whereas wind speed influences for the winter time. Also, among four greenhouse gas variables and five pollution variables, chlorofluorocarbon, methane, and ozone are more influence on the temperature. The monthly ARE model explained about 43-69% for describing the temperature.