• 물만먹고자라요
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• no.17
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• pp.74-77
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• 2005

"곡물로 키운 소의 고기는 불에 탄 산림, 침식된 방목지, 황폐해진 경작지, 말라붙은 강이나 개울을 희생시키고 수백만 톤의 이산화탄소, 아산화질소, 메탄을 허공에 배출한 결과물이다." 충격 그 자체다. 이 책은 대다수의 사람이 아무런 거부감 없이 받아들이는 '육식 문화' 의 이면에 얼마나 잔인하고 냉혹한 사건들이 숨어 있는가를 적나라하게 보여 준다.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2019.08a
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• pp.241-242
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• 2019

• Journal of ILASS-Korea
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• v.25 no.3
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• pp.132-138
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• 2020

N₂O is hazardous atmosphere pollution matter which can damage the ozone layer and cause green house effect. There are many other nitrogen oxide emission control but N₂O has no its particular method. Preventing further environmental pollution and global warming, it is essential to control N₂O emission from industrial machines. In this study, the thermal decomposition experiment of N₂O gas mixture is conducted by using cylindrical reactor to figure out N₂O reduction and NO formation. And CHEMKIN calculation is conducted to figure out reaction rate and mechanism. Residence time of the N₂O gas in the reactor is set as experimental variable to imitate real SNCR system. As a result, most of the nitrogen components are converted into N2. Reaction rate of the N₂O gas decreases with N₂O emitted concentration. At 800℃ and 900℃, N₂O reduction variance and NO concentration are increased with residence time and temperature. However, at 1000℃, N₂O reduction variance and NO concentration are deceased in 40s due to forward reaction rate diminished and reverse reaction rate appeared.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.2
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• pp.11-18
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• 2018

Biochar is a carbon-rich solid product obtained by the pyrolysis of biomass. It has been suggested to mitigate climate change through increased carbon storage and reduction of greenhouse gas emission. The objective of this study was to evaluate carbon dioxide ($CO_2$) and nitrous oxide ($N_2O$) emissions from soil after various biochars addition. The biochars were produced by pyrolysing pear branch, rice hull and bean straw at $400{\sim}500^{\circ}C$. The treatments were consisted of a control without input of biochar and three type biochars input as 5.0 Mg/ha. Emissions of $CO_2$ and $N_2O$ from upland soil were determined using closed chamber for 8 weeks at $25^{\circ}C$ of incubation temperature. It was shown that the cumulative $CO_2$ were 207.1 to $255.2g\;CO_2/m^2$ for biochar input treatments and $258.6g\;CO_2/m^2$ for the control after experimental periods. The cumulative $CO_2$ emission was slightly decreased in biochar input treatment compared to the control. It was appeared that cumulative $N_2O$ emissions were $2,890.6mg\;N_2O/m^2$ for control, 379.7 to $525.2mg\;N_2O/m^2$ for biochar input treatment at the end of experiment. All biochar treatments were found to significantly reduce $N_2O$ emission by 82~87%. Consequently the biochar from byproducts such as pear branch, rice hull and bean straw could suppress the soil $N_2O$ emission. The results from the study imply that biochar can be utilized to reduce greenhouse gas emission from the upland field.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.9
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• pp.1045-1050
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• 2014

$N_2O$(Nitrous Oxide) is known as the third major GHG(Green House Gas) following $CO_2$(Carbon Oxide) and $CH_4$(Methane). The GWP(Global Warming Potential) factor of $N_2O$ is 310 times as large as that of $CO_2$ because $N_2O$ in the atmosphere is very stable, and it becomes a source of secondary contamination after photo-degradation in the stratosphere. Investigation on the cause of the $N_2O$ formation have been continuously reported by several researchers on power sources with continuous combustion form, such as a boiler. However, in the diesel engine, research on $N_2O$ generation which has effected from fuel components has not been conducted. Therefore, in this research, author has investigated about $N_2O$ emission rates which was changed by nitrogen and sulfur concentration in fuel on the diesel engine. The test engine was a 4-stroke direct injection diesel engine with maximum output of 12 kW at 2600rpm, and operating condition of that was set up at a 75% load. Nitrogen and sulfur concentrations in fuel were raised by using six additives : nitrogen additives were Pyridine, Indole, Quinoline, Pyrrol and Propionitrile and sulfur additive was Di-tert-butyl-disulfide. In conclusion, diesel fuels containing nitrogen elements less than 0.5% did not affect $N_2O$ emissions in the all concentrations and kinds of the additive agent in the fuel. However, increasing of the sulfur additive in fuel increased $N_2O$ emission in exhaust gas.

• Clean Technology
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• v.25 no.1
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• pp.63-73
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• 2019

Numerical analysis was done to evaluate the chemical reaction and the reduction rate inside of selective non-catalytic reduction to denitrification in combustion process. The $NO_X$ reduction in selective non-catalytic reduction is converted to not only nitrogen but also nitrous oxide. Simultaneous $NO_X$ reduction and nitrous oxide generation suppressing is required in selective non-catalytic reduction because nitrous oxide influences the global warming as a greenhouse gas. The current study was performed compare the computational analysis in the same temperature and amount of NaOH, and in comparison with the previous research experiments and confirmed the reliability of the computational fluid dynamics. Additionally, controlling the addition amount of NaOH to predict the $NO_X$ reduction efficiency and nitrous oxide production. Numerical analysis was done to check the mass fraction of each material in the measurement point at the end of selective non-catalytic reduction. Experimental Value and simulation value by numerical analysis showed an error of up to 18.9% was confirmed that a generally well predicted. and it was confirmed that the widened temperature range of more than 70% $NO_X$ removal rate is increased when the addition amount of NaOH. So, large and frequent changes of the reaction temperature waste incineration facilities are expected to be effective.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.1
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• pp.153-160
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• 2021

Nitrous oxide is a global warming substance and is known as the main cause of the destruction of the ozone layer because its global warming effect is 310 times stronger than carbon dioxide, and it takes 120 years to decompose. Therefore, in this study, we investigated the characteristics of NOx emission from N2O reduction by thermal decomposition of N2O. Bunsen premixed flames were adopted as a heat source to form a high-temperature flow field, and the experimental variables were nozzle exit velocity, co-axial velocity, and N2O dilution rate. NO production rates increased with increasing N2O dilution rates, regardless of nozzle exit velocities and co-axial flow rates. For N2O, large quantities were emitted from a stable premixed flame with suppressed combustion instability (Kelvin Helmholtz instability) because the thermal decomposition time is not sufficient with the relatively short residence time of N2O near the flame surface. Thus, to improve the reduction efficiency of N2O, it is considered effective to increase the residence time of N2O by selecting the nozzle exit velocities, where K-H instability is generated and formed a flow structure of toroidal vortex near the flame surface.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.7
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• pp.1074-1081
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• 2021

Nitrous oxide (N₂O) is one of the six major greenhouse gases and is known to produce a greenhouse ef ect by absorbing infrared radiation in the atmosphere. In particular, its global warming potential (GWP) is 310 times higher than that of CO₂, making N₂O a global concern. Accordingly, strong environmental regulations are being proposed. N₂O reduction technology can be classified into concentration recovery, catalytic decomposition, and pyrolysis according to physical methods. This study intends to provide information on temperature conditions and reaction time required to reduce nitrogen oxides with cost. The high-temperature ranges selected for pyrolysis conditions were calculated at intervals of 100 K from 1073 K to 1373 K. Under temperatures of 1073 K and 1173 K, the N₂O reduction rate and nitrogen monoxide concentration were observed to be proportional to the residence time, and for 1273 K, the N₂O reduction rate decreased due to generation of the reverse reaction as the residence time increased. Particularly for 1373 K, the positive and reverse reactions for all residence times reached chemical equilibrium, resulting in a rather reduced reaction progression to N₂O reduction.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.426-427
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• 1999

최근 자료에 의하면 우리나라의 온실가tm 총 배출량은 1990년을 기준으로 이산화탄소 6,927만 8천톤, 메탄 135만 2천톤, 아산화질소 1만 2천톤으로 추정되고 있다. 최근 증가 추세가 비교적 큰 것으로 알려진 메탄의 경우, 농업 분야와 폐기물매립 분야의 배출량이 전체 배출량의 80％를 차지하고 있다. 특히, 농업 분야의 산업 활동이 감소될 것으로 전망되고 있으므로, 폐기물 매립에 의한 메탄의 배출량은 그 비중이 더 커질 것으로 전망된다.(중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.129-130
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• 2002

지구온난화를 유발하는 온실효과기체의 대표적인 성분으로는 이산화탄소, 메탄, 프레온류, 아산화질소 등을 들 수 있으며, 각 성분의 대기 중 농도는 산업화의 진행에 따라 지속적이고 철저한 증가 추세를 보이고 있다. 이에 따라 지구 온난화 현상은 점차 가속화되는 경향을 보이고 있으며, 온실효과기체가 현재와 같은 증가율로 증가하게 되면 2030년대에는 지구 전체의 평균기온이 현재에 비해 약 1.5-3.5$^{\circ}C$ 상승하게 되고, 기후 변동, 생태계의 교란, 해수면 상승, 토양침식 증가 등의 결과가 예측된다. (중략)