• Title/Summary/Keyword: Atmospheric environment

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A Review of Photocatalytic Treatment for Various Air Pollutants

  • Reddy, P. Venkata Laxma;Kim, Ki-Hyun;Kim, Yong-Hyun
    • Asian Journal of Atmospheric Environment
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    • v.5 no.3
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    • pp.181-188
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    • 2011
  • Photocatalysis is a photochemical catalytic reaction which is a highly promising tool for the environmental cleanup process. It is very effective in treatment of environmental pollutants by its unique redox property. It has wide applications in the treatment of atmospheric pollutants (e.g., nitrogen dioxide, trichloroethylene, volatile organics, hydrogen sulfide, benzene, etc) through oxidative removal and by disinfection (aeromicro flora). In this research, the fundamental aspects of photocatalysis are described with respect to the composition of catalysts, experimental conditions (e.g., temperature, duration, etc), and interfering factors (e.g., catalyst deactivation).

Determination of Size Distribution of Atmospheric Paticulates in Urban Air Using Andersen Sampler (Andersen 시료채취기를 이용한 도시대기중 부유입자상 물질의 입도분포 측정)

  • 이용근;김만구;원정호
    • Journal of Korean Society for Atmospheric Environment
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    • v.1 no.1
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    • pp.93-98
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    • 1985
  • Mass size distribution of atmospheric particulates were measured using an Andersen using an Andersen sampler in urban air. The atmospheric particulates were fractionated in eight stages of an Andersen sampler operating at 28.4$\ell/min$ and collected on polyester sheets. A quartz filter was placed behind the last stage collect permeated partculates. The size distribution of atmospheric particulates were divided around 1-2 $\mu$m into two groups, coarse and fine particulates regardless of sampling times. The variation of course particulates concentration was higher than fine particulates among sampling times. Different meterorological conditions and natural phenomena brought high variation of course particulates' concentration. The rain caused removal of coarse particulates seriously and the yellow and may take part in a increase of the course particulates in spring. The average concentration of atmospheric particulates to be collected by Andersen sampler was 170.8 $\mug/m^3$ during 3 times of sampling. Among them the average concentration of atmospheric particulates which could penetrated under a bronchi and alveoli were 70.4$\mug/m^3$ and 36.6$\mug/m^3$ respectively.

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Economic Evaluation of a Workplace Occupational Health Nursing Service: Based on Comparison with Atmospheric Environment Managing Engineer (사업장 내 간호사 활동의 경제성 분석: 간호사와 대기환경관리기사 비교를 통하여)

  • Jung, Hye-Sun;Lee, Bokim
    • Journal of Korean Academy of Nursing
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    • v.43 no.4
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    • pp.507-516
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    • 2013
  • Purpose: The purpose of this study was to use cost-benefit analysis of activity to clarify the economic effect of prepared nurses versus atmospheric environment managing engineers as healthcare managers. Methods: For the study 111 workplaces were surveyed, workplaces in which nurses or atmospheric environment managing engineers were employed as healthcare managers. The survey content included annual gross salaries, participation in external job training, costs in joining association covered by the company, location and year of construction of the healthcare office, various kinds of healthcare expenditures, costs in operating healthcare office, health education, and activity performance in the work of environment management. Results: In the case of the healthcare manager being a nurse, benefit was larger than input costs at a ratio of 2.31. On the other hand, in the case of healthcare manager being an atmospheric environment managing engineer, input costs were larger than benefits (benefit-cost ratio 0.88). Conclusion: Results indicate that nurses are an effective healthcare human resource and can offer good quality healthcare service. Therefore companies should hire nurses and actively promote the economic efficiency of nurses in workplace.

Study on the Variation of Nighttime Cooling Rate Associated with Urbanization (도시화에 의한 야간 대기 냉각율 변화에 관한 연구)

  • Lee, Soon-Hwan;Park, Myung-Hee;Kim, Hea-Dong
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.1
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    • pp.83-90
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    • 2008
  • In order to clarify the urbanization intensity of Daegu Metropolitan and its characteristics, comparative study on the variation of the cooling rate of two different sites was carried out using observation data for 40 years by Korea Meteorological Adminstration. Daegu Metropolitan and Chupungnyung represent well urbanized and rural areas, respectively. In comparison with Chupungnyung, yearly mean temperature at Daegu Metropolitan increases rapidly and especially the differences of minimum temperature increasing rate during 40 years becomes greater. These differences of regional warming are caused by the different urbanization intensity between two sites. And the impact of anthropogenic heat due to urbanization should be stronger in nighttime than in daytime. Sensible heat advection by regional wind during 6 hours from 18 LST contributes to atmospheric cooling. For this reason wind speed is in proportion to cooling rate of atmosphere. However, wind after 24 LST induces the warm air advection and makes decrease the cooling rate in urban area. Although the cooling rates between Daegu Metropolitan and Chupungnyung are some different, the variation tendencies of cooling rate of two site are almost same. Therefore atmospheric cooling rate in nighttime tends to be associated with the intensity of wind speed.

Airborne Asbestos Concentrations of Various Locations in Seoul (서울지역의 Asbestos 環境濃度分布)

  • 兪榮植;金鍾奎
    • Journal of Korean Society for Atmospheric Environment
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    • v.5 no.2
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    • pp.36-41
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    • 1989
  • Concentrations of atmospheric asbestos at 5 sites in the central Seoul area, were determined by phase contrast microscopy. The observed numbers of asbestos per liter of air were: maximum 4.51, minimum 0.72 and average 2.20. The direct relationship between asbestos concentration at each sampling site and automobile traffics was not demonstrated. But the more there are automobile traffics, the higher asbestos concentratiof of total fibers is.

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On the Short Term Air Pollution Dispersion Model for the Single Souce -Diffusion Experiment With Tracer Gas- (單一 排出源大氣汚染 短期모델에 관한 硏究 -Tracer Gas에 의한 擴散實驗-)

  • 李鍾範;姜寅求
    • Journal of Korean Society for Atmospheric Environment
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    • v.5 no.2
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    • pp.84-96
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    • 1989
  • To evaluate the short term air pollution dispersion model, the diffusion experiment was conducted on the flat terrain near Chuncheon. Sulfur hexafluoride $(SF_6)$ gas was used to determine the horizontal spread of plume $(\sigmay)$ for calculated by CRSTER model. Results show that CRSTER model underestimates $\sigma$y because averaging time adjustment is not applied to calculate the $\sigma$y. The scheme that can estimate the atmospheric stability more accurate than Turner method, was presented.

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Adsorption and Oxidation Reaction Rate of $SO_2$ in Slurries of Activated Carbon (활성탄 슬러리를 이용한 $SO_2$ 가스의 흡착 및 산화반응 속도)

  • 최용택;신창섭;이태희
    • Journal of Korean Society for Atmospheric Environment
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    • v.3 no.1
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    • pp.41-46
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    • 1987
  • Adsorption and reaction studies were made for the catalytic oxidation in aqueous slurries of activated carbon at room temperature and atmospheric pressure. In order to analyze the reaction rate, the mechanism was assumed by the steps of nonhomogeneous catalytic reaction. The experimental result show that oxidation rate was controlled by the reaction between adsorbed molecular oxygen and sulfur dioxide on the catalyst surface. Ar room temperature, the equat5ion of reaction rate was given as $ro_2 = 2.49 \times 10^{-7} P_O_2^{0.604}$.

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A Study on Air Pollution Prediction Using Adaptive Lattice Altorithm (적응격자 알고리즘을 이용한 대기오염 예측에 관한 연구)

  • 홍기용;김신도;김성환
    • Journal of Korean Society for Atmospheric Environment
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    • v.2 no.3
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    • pp.52-56
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    • 1986
  • In this paper a adaptive LMS(least mean-square) lattice predictor, which is composed of the adaptive lattice algorithm and LMS algorithm by Widrow-Hopf, is used to predict the future air pollution of the extraordinary levels in the environmental system. This prediction algorithm is applied to the one-step forward prediction of atmospheric CO concentration by using real observed data. Computer simulation proves that the power in the forward error sequences decreases as the number of stages in the lattice is increased.

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Atmospheric and Air Quality Modeling for Evaluation of Atmospheric Environment around the Gimhae Area (김해지역 대기환경 평가를 위한 기상장 및 대기질 모델링)

  • 이화운;노순아;정우식;임헌호;이강열
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.433-434
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    • 2003
  • 1980년대 이후 대표적인 대기오염 지표인 아황산가스와 총먼지 오염도는 그동안 정부가 지속적으로 추진해 온 산업과 난방부문의 저황연료 등 청정연료공급 대책에 힘입어 개선되는 추세를 보이고 있다. 그러나 1990년대에 들어서는 자동차 증가와 유기 용재 사용의 급증으로 질소산화물, 휘발성유기화합물질 등의 배출이 증가하고 있으며, 이로 인한 대기오염의 심화 및 스모그와 시정장애 등 새로운 오염이 심각해지고 있고 이에 대한 대책이 시급한 실정이다. (중략)

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Major Factors Affecting PM2.5 Water Content in Seoul and Gosan (서울과 고산의 미세입자 수분함량에 영향을 미치는 주요 인자)

  • Choi E. K;Kim Y.P
    • Journal of Korean Society for Atmospheric Environment
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    • v.20 no.6
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    • pp.803-810
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    • 2004
  • Water contents in fine particles at Seoul and Gosan are estimated by using a gas/particle equilibrium model, SCAPE (Simulating Composition of Atmospheric Particles at Equilibrium). Also, sensitivity of particulate inorganic ionic concentrations on the total ionic species is estimated. Water content at Gosan is more sensitive to ambient relative humidity (RH) than Seoul. At both sites water content is most sensitive to sulfate concentration among sulfate, nitrate, and ammonium. Solid salts levels and compositions are also studied.