• Journal of Environmental Science International
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• v.16 no.5
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• pp.665-670
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• 2007

In this study, we evaluated the property change and relationship between hematological and biochemical parameters in exposure group and control group by multiple inhalation exposure, of $NO_2$. In case of leukocyte, change of hematological property increased significantly in statistics (p<0.05) in mice experiment. in case of hematocrit of exposure group, it was of decreased significantly in statistics. the tendency of hemoglobin and hematocrit was similar to all for three case. in case of methmoglobin that of the exposure group in mice experiment was meaning increased(p<0.05). For the $NO_2$ influence in biochemical property, total protein and triglyceride was decreased but not significant in statistics, albumin was decreased in the exposure group in the animal experiments, blood urea nitrogen and creatinine increased significantly in statistics in the animal experiments. uric acid and lactate dehydrogenase in serum increased significantly in the exposure group. We have to evaluate risk assessment for the $NO_2$ of indoor air pollutant in low concentration and long time.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.3
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• pp.223-229
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• 1987

This study was carried out to find out the effects of nitrogen dioxide gas on vegetable crops. Chinese cabbage, radish, tomato and cucumber were used for this experiment, and these crops were fumigated with various concentration of nitrogen dixoide gas for 2 hours under the different condition of light and soil water at the vegetable growth stage. The results obtained were as follows. The crops damages measured by percentage of leaf destruction were more severe at the night time fumigation than at the day time, under the full sun condition than under the shading, and at the higher soil water contents than at the low soil water contents. The cucumber plant showed the highest resistance to nitrogen dioxide gas and tomato plant showed the least resistance. As the nitrogen dioxide concentration increased from $0.05mg/{\ell}$ to $0.2mg/{\ell}$, the N contents in leaves of each crops were increased, and the increment of N contents in leaves was higher by fumigation at the night than at the day time. The increment of N contents in leaves showed possive correlation with the percentage of leaf destruction significantly.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.11
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• pp.1297-1308
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• 2011

This research investigates the application of ZnO (zinc oxide) nanoparticles and $TiO_2$ (titanium dioxide) nanoparticles to polypropylene nonwoven fabrics via an electrospinning technique for the development of textile materials that can decompose harmful gases. To fabricate uniform ZnO nanocomposite fibers, two types of ZnO nanoparticles were applied. Colloidal $TiO_2$ nanoparticles were chosen to fabricate $TiO_2$ nano- composite fibers. ZnO/poly(vinyl alcohol) (PVA) and $TiO_2$/PVA nanocomposite fibers were electrospun under a variety of conditions that include various feed rates, electric voltages, and capillary diameters. The morphology of electrospun nanocomposite fibers was examined with a field-emission scanning electron micro- scope and a transmission electron microscope. Decomposition efficiency of gaseous materials (formaldehyde, ammonia, toluene, benzene, nitrogen dioxide, sulfur dioxide) by nanocomposite fiber webs with 3wt% nano-particles (ZnO or $TiO_2$) and 7$g/m^2$ web area density was assessed. This study shows that ZnO nanoparticles in colloid were more suitable for fabricating nanocomposite fibers in which nanoparticles are evenly dispersed than in powder. A heat treatment was applied to water-soluble PVA nanofiber webs in order to stabilize the electrospun nanocomposite fibrous structure against dissolution in water. ZnO/PVA and $TiO_2$/PVA nanofiber webs exhibited a range of degradation efficiency for different types of gases. For nitrogen dioxide, the degradation efficiency was 92.2% for ZnO nanocomposite fiber web and 87% for $TiO_2$ nanocomposite fiber web after 20 hours of UV light irradiation. The results indicate that ZnO/PVA and $TiO_2$/PVA nano- composite fiber webs have possible uses in functional textiles that can decompose harmful gases.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.4
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• pp.76-84
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• 2014

Preventive conservation is one of most important issues in the field of conservation for paper-records. Many researchers have been studied environmental factors such as effects of humidity, temperature, biological attack and air pollutants. Air pollutants strongly associated with oxidative and hydrolytic degradation of cellulose. It is important to control air pollutants in storage environment to improve stabilities of conservation environment. Four paper samples have been analyzed for their accelerated aging characteristics by air pollutants, sulfur dioxide, nitrogen dioxide, ozone, carbon monoxide. Physical and optical properties and weight molar masses(Mw) showed that interactions between air pollutants and paper sample. Nitrogen dioxide, ozone caused severe damage to cellulose in paper by hydrolytic and oxidative decompositions during aging.

• Journal of Preventive Medicine and Public Health
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• v.32 no.2
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• pp.191-199
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• 1999

Objectives: To examine the relationship between air pollution exposure and mortality in Seoul for the years of 1991-1995, Methods: Daily counts of death were analyzed by general additive Poisson model, with adjustment for effects of secular trend, seasonal factor, day of the week, heat wave, temperature, and humidity. Pollution variables were ozone, nitrogen dioxide, total suspended particles(TSP), and sulfur dioxide. Results: Daily death counts were associated with ozone(1 day before), nitrogen dioxide(1 day before), TSP(2 days before), sulfur dioxide(2 days before). The association with ozone was most statisfically significant and independent of other air pollutants. Increase of 100 ppb in ozone was associated with 0%(95% Cl= 2%-10%) increase in the daily number of death, This effect was greater in persons aged 65 and older. The relative risks of death from respiratory disease and cardiovascular disease were greater than for all-cause mortality in each pollutant. After ozone level exceeds 25 ppb, the dose-response relationship between mortality and ozone was almost linear. However, the effect of TSP, sulfur dioxide, and nitrogen dioxide on mortality might be confounded with each other. Conclusion: Daily variations in air pollution within the range currently occurring in Seoul might have an adverse effect on daily mortality.

• 한국연소학회:학술대회논문집
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• 2001.06a
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• pp.31-45
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• 2001

The effect of adding carbon dioxide to methane-air flame was investigated experimentally. Measurements included extinction limits, flame temperature and photographic investigation of flame. A diffusion flame was stabilized between counterflowing streams of methane diluted with carbon dioxide and air diluted with carbon dioxide. Extinction limits and temperature for such flames were measured over a wide parametric range and were compared with those for other flames that fuel or oxidant was diluted with nitrogen or argon. The experimental results indicate that extinction phenomena can be explained by thermal effect and as an amount of carbon dioxide in fuel or oxidant increases, greatly as compared with other flames flame-temperature falls and flame-thickness is reduced.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.383-386
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• 1988

In MOS integrated circuits, annealing after oxidation process is necessary to improve physical properties of silicon dioxide. With subsequent annealing in inert gases such as nitrogen or argon, and excess silicon bond is allowed time to complete the oxidation and surface charge density is reduced. In this paper, we will present effects of the rapid thermal annealing on silicon dioxide. In order to evaluate characteristics of silicon dioxide, we analyzed C-V curve dependent on annealing time and temperature, and presented variation of fixed oxide charge.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.05b
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• pp.261-264
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• 2003

We try to distribute air pollution sources at target area. The complex method is used to distribute air pollution sources. Most of people, However, want to simple indicator as standard for express air pollution source. In many area, air pollution is caused by different types of sources. The general type is point source, such as tall stack of power plants and oil refineries stacks. A second type is areal source, such as local industry and transportation. In this aspect, the ratio of sulfur dioxide to nitrogen oxides (RSN =SO$_2$/NOx)is an indicator of air pollution source. the role of this ratio is to show the characteristics at target area of the relationship the point and the areal source. (omitted)

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.591-594
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• 2008

지구 온난화 문제의 심각성이 대두되면서 이산화탄소 저감 기술에 대한 관심이 증폭되고 있다. 가장 이상적인 방법은 탄소가 포함되지 않은 청정 재생 에너지원이지만, 에너지 공급 규모 면에서 보면 근미래에도 화석 연료가 에너지 수요에 대한 주요 공급원으로 남아있을 것이라는 의견이 지배적이다. 많은 화석 연료 중 천연가스는 탄소 배출량이 가장 적은 청정 연료로 지난 10년간 수요가 폭발적으로 증가해왔다. 이를 고려해볼 때 탄소 배출량이 적은 천연가스를 생산하면서 이산화탄소를 격리 시킬 수 있는 기술은 매우 매력적이다. 본 연구에서는 심해저의 메탄 하이드레이트로 부터 천연가스를 생산하는 기술로서 이산화탄소와 질소의 혼합 가스를 사용하는 기술 개발의 일환으로 혼합 가스에 의한 메탄 하이드레이트 해리 속도를 $^{13}C$ NMR을 이용해 측정한 결과를 제시하고자 한다.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.2
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• pp.33-38
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• 1987

A pilot study on indoor air concentrations of nitrogen dioxide $(NO_2)$ was undertaken in the Seoul area, Korea dudring February-April 1986. Indoor and outdoor data on nitrogen dioxide concentrations were obtained for 48 private residences. Personal exposure to $NO_2$ was also investigated. Indoor outdoor ratio of $NO_2$ concentrations was 0.87, while the correlations between the indoor and outdoor levels were less than 0.50 for $NO_2$. Homes with an unvented space heater had average living room $NO_2$ concentrations approximately double those with a vented space heater. Residences with smokers have significantly higher living room $NO_2$ levels than those without smokers.