• 한국환경보건학회지
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• 제34권3호
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• pp.199-206
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• 2008

This study was conducted to estimate nitrogen dioxide levels and health risk in various locations/situations for two groups. The nitrogen dioxide levels were measured for residents of a study group (industrial area within 5 km) and a control group (15 km farther), respectively using the nitrogen dioxide filter badge as a passive sampler from August, 2006 to September, 2006. The means of indoor, outdoor, work and personal levels of nitrogen dioxide were $34.65{\pm}1.95\;{\mu}g/m^3$, $34.83{\pm}11.78\;{\mu}g/m^3$, $34.98{\pm}19.11$ and $35.38{\pm}10.74$ respectively in the study area. Mean ratio of indoor to outdoor $NO_2$ concentration was 0.99. The means of indoor, outdoor and personal level of nitrogen dioxide were $23.66{\pm}7.19\;{\mu}g/m^3$, $18.22{\pm}4.06\;{\mu}g/m^3$ and $27.27{\pm}18.93\;{\mu}g/m^3$ respectively in the control area. Mean ratio of indoor to outdoor $NO_2$ concentration was 1.39. People spent 80.9% of their time in indoor at the study area and 76.9% at the control area. The percentages of time spent in outdoor were 14.9% and 20.9% at the study area and the control area respectively. The percentages of time spent in a car were 4.2% and 2.2% in the study and control areas respectively. The levels of indoor, outdoor, workplace nitrogen dioxide in the study area and the control area were found below the permissible level of health-hazardous effects.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.248-249
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• 2014

Photocatalytic cement is receiving attention due to its high oxidation power that oxidizes nitrogen oxides (NOx), thus contributing to clean atmospheric environment. However, there has not been a thorough investigation on durability of a parent material, cementitious material, as a result of photocatalytic reactions. In this study, durability of photocatalytic cementitious materials exposed to nitrogen dioxide (NO₂) gas was examined. Titanium dioxide (TiO₂) nanoparticles containing cement paste samples were exposed to cycles of NO₂ with UV light, followed by wetting and drying to simulate environmental condition. The surface of samples was characterized mechanically, chemically, and visually during the cycling. The results indicate that the photocatalytic efficiency decreased with continued NO₂ oxidation due to calcium carbonate formation. The pits found from SEM demonstrate that chemical deterioration have occurred, such as acid attack or leaching. In conclusion, the photocatalytic reactions and its product could alter cementitious materials chemically and mechanically which could further affect long-term durability.

• 한국대기환경학회지
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• 제17권3호
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• pp.251-258
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• 2001

Indoor and outdoor nitrogen dioxide(NO$_2$) concentrations of 122 houses were measured and compared with measurements of personal NO$_2$ exposure simultaneously . Time activity patterns were used to determine the impacts on NO$_2$ exposure assessment and time weighed average model to estimate the personal NO$_2$ exposure. Most people spent their times more than 80% of indoor and more than 50% in home, respectively. Personal NO$_2$ esposure was found to be significantly associated with both indoor NO$_2$ concentration(r=0.70) and outdoor NO$_2$ concentration (r=0.68). Using time weighted average model, personal NO$_2$ exposure was estimated with NO$_2$ measurements in indoor home, indoor workplace and outdoor home. The estimated NO$_2$ measurements were significantly correlated with measured personal exposures(r=0.69, N=122). For the difference between measured and estimated NO$_2$ exposures by multiple regression analysis showed that NO$_2$ concentrations in near workplace and other outdoors of no NO$_2$ measurements affected the personal NO$_2$ exposures(p=0.023).

• Tuberculosis and Respiratory Diseases
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• 제44권6호
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• pp.1408-1413
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• 1997

저자들은 1997년 2월 조명공장에서 우연히 누출된 이산화질소 흡입 6시간만에 호흡곤란과 함께 폐부종 소견을 보인 환자를 체험하였기에 이에 문헌고찰과 함께 보고하는 바이다.

• Tuberculosis and Respiratory Diseases
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• 제40권4호
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• pp.436-441
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• 1993

경북대학교병원 호흡기내과에서 1992년 10월 화학약품제조공장에서 누출된 이산화질소의 흡입으로 인하여 급성폐손상을 받은 남자 2예를 치험하였기에 문헌고찰과 함께 보고하였다.

• 한국환경과학회지
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• 제14권1호
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• pp.9-14
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• 2005

This study evaluated the hazard caused by $NO_{2}$, an oxidant generated in the process of welding. We com­pared hematological and biochemical parameters in workers who chronically inhale $NO_{2}$ and office workers not exposed to $NO_{2}$. $NO_{2}$ exposure affected the hematological and biochemical parameters. Increasing $NO_{2}$ concen­trationincreased the number of leukocytes, while decreasing the number of erythrocytes. Blood urea nitrogen, cre­atinine, uric acid, and lactate dehydrogenase were increased, while total protein and triglycerides were decreased. The mean concentration of $NO_{x}(NO_{2}^{-}/NO_{3}^{-})$ in the serum of welders and the control group was $35.97{\pm}2.85\;and\;55.40{\pm}5.81\;{\mu}mol/L,$ respectively. The difference was significant (p < 0.05), although $NO_{2}^{-}$ was not detected in the serum.

• 한국대기환경학회지
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• 제2권1호
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• pp.55-72
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• 1986

This study was made to determine the factors involving personal exposure levels of nitrogen dioxide for housewives living in urban area in two seasons, winter and summer. Nitrogen dioxide was measured with a small passive sampler containing triethanolamine. The samplers were set for 24 hours at three points. They were places: on the collar of the housewife to investigate the personal exposure level, near the TV in the living room (indoor level), and near the porch of their house (outdoor level). The subjects recorded the times of cooking using a gas range, using a kitchen ventilator, passive smoking, kerosene heater, total number of minutes at an open window, going out of home, etc.$\ldots. There was an apparent increase in personal exposure level in the case of the unvented heater and also an increase by cooking on a gas range. There was no marked increase in the other situations. There was an increase in the indoor level by cooking on a gas range, only in western style cooking in the winter season. Through these observations, we concluded that personal exposure level of nitrogen dioxide was strongly related to indoor nitrogen dioxide level, and factors involving indoor nitrogen dioxide level seemed different between winter and summer. The most significant difference in nitrogen dioxide level was indoor pollution in the winter and the outdoor environment in the summer. The maximum personal exposure level appeared in the western and tenement house in the winter and the traditional korean house in the summer.

• 센서학회지
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• 제16권2호
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• pp.91-96
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• 2007

The characteristic of tellurium thin films was studied for detecting nitrogen dioxide gas at room temperature. The film was deposited on $Al_{2}O_{3}$ substrate by using thermal evaporator. The subsequent process was heat treatment by several conditions. (temperature, flowed gases) Surface and grain boundary was investigated using SEM. The results showed that resistance of the tellurium film decreases reversibly in the presence of nitrogen dioxide. The sensitivity of this device depends on the gas concentration and detect lower concentrations less than 10 ppm.

• Journal of Plant Biology
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• 제14권3호
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• pp.43-46
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• 1971

Losses of nitrogenin the gaseous form were determined with closed systems in the filed under different vegetation types. Ammonia volatilization was greatest from the pine stand, and least from the sod stand, and was greatly reduced in all three sites in the rainy season due to the low temperature. There were only insignificant differences in the nitrogen dioxide volatilization from the soil of the three vegetation types. Losses of ammonia and nitrogen dioxide at various soil depth also showed little variation. Evidently the microbial activity responsible for the $NO_2$ loss was relatively unaffected by the changes in temperature and soil moisture content during the investigation.

• 한국환경보건학회지
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• 제34권3호
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• pp.183-187
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• 2008

Indoor air quality can be affected by indoor sources, ventilation, decay, and outdoor levels. Various indoor and out-door combustion sources produce nitrogen dioxide ($NO_2$), which is a by-product of high temperature fossil fuel combustion. Especially, the presence of gas ranges and smoking have been identified as major factors contributing to indoor $NO_2$ exposures. In this study, we compared an industrial complex area with a country area by assessing the personal exposure to $NO_2$with measurements of indoor and outdoor $NO_2$ levels in residences and by house characteristics and questionnaire. Personal exposure concentrations were significantly correlated with indoor $NO_2$ concentrations of residences in both the industrial complex area and the country area with correlation coefficients of 0.561 and 0.664, respectively, compared to outdoors. Multiple regression analysis, indicated that indoor $NO_2$ levels in residences were only affected by outdoor levels (p = 0.000) in spite of higher indoor sources such as smoking. Therefore, it is suggested that outdoor air quality as well as indoor air quality should be considered in the reduction of the personal exposure to air pollutants.