• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.87-88
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• 1999

최근 들어 서울을 중심으로 한 수도권 지역에서는 여름철 오존주의보 발령이 빈번해지면서 광화학 반응에 의한 대기중 오존농도 상승에 많은 관심을 보이고 있다. 휘발성 유기물질 (Volatile Organic Compounds)은 광화학 반응을 통해 오존을 생성시키는 대표적인 대기오염 물질로 알려져 있으며 주로 자동차, 석유정제, 석유화학, 도장산업 등에서 배출되는 것으로 알려져 있다. 이렇나 VOC는 $NO_x$와 함께 대기중 오존농도 저감을 위한 대상물질로써 NOx 배출량 규제와 동시에 VOC 농도 및 특성 또한 면밀히 검토되어야 한다.(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.58-59
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• 2000

오존은 공간적.시간적 변동이 매우 큰 대기오염물질로 서울시의 27개 대기오염 자동측정망에서 실시간으로 측정.감시되고 있으며, 오존의 농도가 높아지는 여름철에는 오존경보제를 실시하고 있다. 특히 오존의 농도는 일사, 풍향, 풍속 등의 기상인자, $NO_x$, VOCs 등 전구물질의 농도, 그리고 지형에 따라서 영향을 받는 것으로 알려져 있다. 따라서, 본 연구에서는 서울지역에 대한 기하학적 축소모형을 제작하여 풍동내에서 풍향.풍속을 측정하여 지형에 따른 바람의 특성을 파악하였다. (중략)

• Korean Journal of Environmental Agriculture
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• v.2 no.1
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• pp.6-12
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• 1983

A pot experiment was conducted to clarify the Cd uptake and levels affecting yield loss according to the growth stages of rice plant. The cadmium was treated with several Cd compounds $Cd(NO_3)_2$, $CdCl_2$, $CdSO_4$, $CdCO_3$ and CdS at various concentrations of 0,5,10,25, and 50ppm in soils. The increasing rate of Cd compounds applied to soils increased the Cd content in plant as well as grains but the yield was decreased at high cadmium levels. Cd concentration in soil which could affect the yield decrease were 12.9ppm for $Cd(NO_3)_2$; 21.5ppm, $CdSO_4$; 25.8ppm, $CdCl_2$; 33.2ppm, $CdCO_3$; and 97.6ppm, CdS respectively. Cd concentration in soil reaching at 1ppm of Cd content in brown rice were 13.8ppm from $Cd(NO_3)_2$; 14.4ppm, $CdCl_2$; 16.9ppm, $CdSO_4$; and 19.2ppm, $CdCO_3$, respectively. Cd content in brown rice could be expected with the Cd content in plant at panicle formation stage.

• Analytical Science and Technology
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• v.15 no.5
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• pp.427-432
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• 2002

The combustion behavior of heavy oil and its emulsion with water was evaluated. The concentration of $SO_x$ in the combustion gas of emulsion oil was reduced to 57% with respect to that of the combustion gas from neat heavy oil. Also, the concentration of $NO_x$ in the combustion gas of emulsion oil was reduced to 67% with respect to that of the combustion gas of neat heavy oil. These reductions of $SO_x$ in the combustion gas of emulsion oil seems to be due to the reaction with salts included in surfactant of emulsion oil. Also, the combustion efficiency of emulsion oil is evaluated to be about 6% higher than that of neat heavy oil.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.1212-1213
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• 2004

The plasmid was used pBR 322 and ${\varphi}X174$ RF DNA. In neutron experiment, damage of pBR 322 and ${\varphi}X174$ RF DNA were observed according to increasing concentration of BSH and neutron dose. Damage of plasmid DNA appeared obvious by increasing of BSH and neutron irradiation. In ${\gamma}-$ radiation experiment, it was carried out like above neutron experiment but damages of two plasmid appeared no differences from the control unlike neutron result.

• Journal of Practical Agriculture & Fisheries Research
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• v.13 no.1
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• pp.35-46
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• 2011

The effects of organic calcium agent(ECa) tree-spray on the mineral nutrition concentration of petiole and fruit skin and quality in grapevines were studied. The calcium concentration of petiole and fruit skin at harvest in 'Campbell Early' by tree-spray after flowering 14days of calcium agent were increased significantly in calcium chloride 0.4%, ECa 250X and MCa 500X compared to control. The calcium concentration of petiole and fruit skin at harvest by ECa tree-spray after 7 days and 14 days flowering were increased significantly compared to control and 21 days after flowering treatment. Also, The calcium concentration of petiole and fruit skin at harvest by tree-spray of ECa 250X and 125X after flowering were increased significantly compared to control and 500X treatment. Fruit quality, fruit cluster weight, cracking fruit and Bitter rot occurrence by ECa tree-spray of treatment time and concentration different showed no difference between control. Phytotoxicity by tree-spray of ECa concentration different not occur to leaf and fruit.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.471-472
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• 1999

각종 산업분야에서 발생되는 NO$_{x}$ 및 VOC$_{s}$ 는 발생원에 따라 농도, 조성 및 가스량, 온도등의 조건이 크게 달라, 이를 경제적이고 효율적으로 제어하기 위해서는 각각의 조건 및 처리목적에 따른 적절한 방지기술의 선정이 필요하다.(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.424-425
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• 1999

오존은 대기 중에 있는 질소산화물 (NO$_{x}$)과 휘발성 유기화합물 (Volatile Organic Compounds, VOCs)이 강한 햇빛과 반응하여 생성되는 2차 오염물질이다. 오존의 농도는 오염물질의 배출과 기상조건, 그리고 대기 중 화학반응이 상호 연결되어 나타난다. 다양한 변수들이 오존 농도 상승에 영향을 미치며, 이러한 과정을 유기적으로 이해하기 위하여 다양한 광화학 수치 모델들이 사용되고 있다.(중략)

• Journal of Environmental Science International
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• v.23 no.5
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• pp.861-871
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• 2014

This study analyzes the characteristics of ozone weekend effect(OWE) in Busan. $O_3$ concentration on Sunday was over 10% higher than that on weekdays in all areas except for Kwangbokdong, Taejongdae, and Joadong. Such a difference was higher in the industrial area than in the residential area. $O_3$ generation was facilitated by the decrease in $NO_X$ emission on Sunday in VOC-limited regime where the VOC/$NO_X$ ratio is low. Low NO concentration in the Sunday morning decreased inhibition of $O_3$. NO-$O_3$ crossover time on Sunday was shorter than that on weekdays which in turn extended the accumulated duration of $O_3$. Future studies can include whether the entire Busan is VOCS-limited or the coastal area is VOCS-limited while the inland area is $NO_X$-limited.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.3
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• pp.676-684
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• 1990

This study is on the pulsating combustion of premixed gas in a Rijke type combustor made of a honeycomb flame holder in a tube. Modelling for the onset condition of the oscillation is made by the ratio of the acoustic power generation based on the analysis of heat transfer to the power loss due to the thermoviscous dissipation and radiation. Experiment is performed for the characteristics of acoustic, thermal and combustion. It is shown that the theoretical modelling for the oscillation may be used as a limit condition. And the combustion analysis for the acoustic power generation is needed for better prediction of the onset condition. Experimental result shows that, by pulsation, the flame length is shortened and the flame temperature is decreased with increase in the heat transfer coefficient. The NO$_{x}$ concentration in the exhaust gas is significantly reduced by pulsation and the concentration of unburned hydrocarbon shows a little increase.e.