• Title/Summary/Keyword: Nitrous Oxides

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The Effects of Methane (CH4) and Nitrous Oxides (N2O) Taxes on the Korean Agricultural Sector (메탄과 아산화질소 배출저감을 위한 과세 효과분석 -한국농업부문을 중심으로-)

  • Lee, Sang-Youp;Kim, Heon-Goo
    • Environmental and Resource Economics Review
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    • v.9 no.5
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    • pp.853-876
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    • 2000
  • The purpose of this paper is to come up with the measures for sustainable development of the agricultural sector in store for the strengthened U.N. Framework Convention on Climate Change. We analyze the spillover effects of Methane and Nitrous Oxides taxes (carbon tax) on the Korean agricultural sector. Unlike the other sectors, the agricultural sector has a unique characteristic generating greenhouse gas in the process of production itself even without consuming much fossil fuel. In order to estimate the impacts of those taxes, non-linear optimization method has been used with various assumed scenarios. The production effect, income and' price effect, and greenhouse gas emission reduction effect in the agricultural sector have been estimated through this method. The empirical results show that the paddy sector has a bigger tax effect than the livestock sector. In the paddy sector, the carbon tax has more impacts in the suburban areas than in the rural areas, while the swine farming section in the livestock sector has a conspicuous income effect in the midst of low greenhouse gas emission effect. These results allude us to apply graded tax rates to the crop, the livestock, and the region of different kind. Even if the agricultural sector has a less tax effect when compared with other industrial sectors, an environmental tax might be an effective measure to prevent global warming.

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A Comparative Study of Gate Oxides Grown in $10%-N_2O$ and in Dry Oxygen on N-type 4H SiC

  • Cheong, Kuan-Yew;Bahng, Wook;Kim, Nam-Kyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07a
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    • pp.17-19
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    • 2004
  • The electrical properties of gate oxides grown in two different processes, which are in 10% nitrous oxide($N_2O$) and in dry oxygen, have been experimentally investigated and compared. It has been observed that the $SiC-SiO_2$ interface-trap density(Dit) measured in nitrided gate oxide has been tremendously reduced, compared to the density obtained from gate oxide grown in dry oxygen. The beneficial effects of nitridation on gate oxides also have been demonstrated in the values of total near interface-trap density and of forward-bias breakdown field. The reasons of these improvements have been explained.

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Transient State Theory of Significant Liquid Structure Applied to Nitrogen Oxides (액체 구조의 천이상태이론의 질소산화물들에 대한 적용)

  • Kim, Sang-Hyung;Pak, Hyung-Suk;Kim, Kak-Choong;Chang, Sei-Hun
    • Journal of the Korean Chemical Society
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    • v.11 no.3
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    • pp.105-110
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    • 1967
  • The transient state theory of significant liquid structure is applied to nitrous oxide and nitrogen tetroxide. The partition functions for the two liquids are derived according to the transient state theory. The various thermodynamic properties; such as, molar volumes, vapor pressures, entropies of vaporization, and critical point properties agree well with the experimental values.

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Effect of Water on the Kinetics of Nitric Oxides Reduction by Ammonia over V-based Catalyst (바나듐계 촉매상에서 암모니아를 이용한 질소산화물의 환원반응속도에 수분이 미치는 영향에 관한 연구)

  • Kim, Young-Deuk;Jeong, Soo-Jin;Kim, Woo-Seung
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.6
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    • pp.73-82
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    • 2012
  • The main and side reactions of the three selective catalytic reduction (SCR) reactions with ammonia over a vanadium-based catalyst have been investigated using synthetic gas mixtures in the temperature range of $170{\sim}590^{\circ}C$. The three SCR reactions are standard SCR with pure NO, fast SCR with an equimolar mixture of NO and $NO_2$, and $NO_2$ SCR with pure $NO_2$. Vanadium based catalyst has no significant activity in NO oxidation to $NO_2$, while it has high activity for $NO_2$ decomposition at high temperatures. The selective catalytic oxidation of ammonia and the formation of nitrous oxide compete with the SCR reactions at the high temperatures. Water strongly inhibits the selective catalytic oxidation of ammonia and the formation of nitrous oxide, thus increasing the selectivity of the SCR reactions. However, the presence of water inhibits the SCR activity, most pronounced at low temperatures. In this study, the experimental results are analyzed by means of a dynamic one-dimensional isothermal heterogeneous plug-flow reactor (PFR) model according to the Eley-Rideal mechanism.

Comparative Reaction Characteristics of Methane Selective Catalytic Reduction with CO Generation Effect in the N2O Decomposition over Mixed Metal Oxide Catalysts (MMO 촉매 하에서 N2O 분해에 대한 메탄 SCR 반응 및 CO 생성 효과의 비교 연구)

  • Park, Sun Joo;Park, Yong Sung
    • Applied Chemistry for Engineering
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    • v.19 no.6
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    • pp.624-628
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    • 2008
  • Nitrous oxide ($N_2O$), known as one of the major greenhouse gases, is an important component of the earth's atmosphere, and gives rise to precursor of acid rain and photochemical smog. For the removal of $N_2O$ and other nitrogen oxides, the SCR reaction system with various reductants is widely used. This study is based on the results of experimental and theoretical examinations on the catalytic decomposition of sole nitrous oxide ($N_2O$) and selective catalytic reduction of $N_2O$ with $CH_4$ in the presence of oxygen using mixed metal oxide catalysts obtained from hydrolatcite-type precursors. When $CH_4$ is fed together with a reductant, it affects positively on the $N_2O$ decomposition activity. At an optimum ratio of $CH_4$ to $O_2$ mole ratio, the $N_2O$ conversion activity is enhanced on the SCR reaction with partial oxidation of methane.

Pyrolysis Effect of Nitrous Oxide Depending on Reaction Temperature and Residence Time (반응온도 및 체류시간에 따른 아산화질소 열분해 효과)

  • Park, Juwon;Lee, Taehwa;Park, Dae Geun;Kim, Seung Gon;Yoon, Sung Hwan
    • 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.

Emissions of Marine Heavy Fuel Oil in the Spray Flame

  • An, Suk-Heon
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.7
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    • pp.1030-1035
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    • 2008
  • Recently, the International Maritime Organization makes an effort for an effective solution against the emissions from shipping in the international maritime industry. The objective of the study was to quantify the exhaust emissions of marine heavy fuel oil in the combustion process of the spray flame. An experiment was performed to measure CO, $CO_2$, NOx, $SO_2$, ${N_2}O$, DS, SOF and the other components with the flame temperature. The sampling probe was directly set up in the flame fields at each position of 103, 324, 545, 766 and 987mm vertically apart from the fuel-injected nozzle in the burner furnace. From the results of the study, it was estimated that approximately 270ppm of oxides of nitrogen (NOx), $1000{\sim}1400ppm$ of sulfur dioxide ($SO_2$), 8ppm of nitrous oxide (${N_2}O$), $2.0{\sim}2.5g/m^3$ of particulate matter (PM) divided with dry soot (DS) and soluble organic fraction (SOF) and $60{\sim}80mg/m^3$ of sulfuric acid. With respect to further development of this work, the emission quantification could also be applied to assessing emission reduction from the international shipping.

Growth and Characteristics of NO/$N_2$O Oxynitrided and Reoxidized Gate Dielectrics for Charge Trapping NVSMs (산화막의 NO/$N_2$O 질화와 재산화 공정을 이용한 전하트랩형 NVSM용 게이트 유전막의 성장과 특성)

  • 윤성필;이상은;김선주;서광열;이상배
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.11a
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    • pp.9-12
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    • 1998
  • Film characteristics of thin reoxidized nitrided oxides were investigated by SIMS analysis and C-V method in order to use the gate dielectric for charge-trap type NVSMs instead of ONO stacked layers. Nitric oxide(NO) annealed film has the nitrogen content sharply peaked at the Si-SiO$_2$ interface, while it is broad for nitrous oxide($N_2$O) ambient. The nitrogen peak concentration increased with anneal temperature and time. The position of nitrogen content in the oxide layer was due to be precisely controlled. For the films annealed NO ambient at 80$0^{\circ}C$ for 30min. followed by reoxidized at 85$0^{\circ}C$, the maximum memory window of 3.5V was obtained and the program condition was +12V, 1msec for write and -l3V, 1msec for erase.

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Development of intelligent model to predict the characteristics of biodiesel operated CI engine with hydrogen injection

  • Karrthik, R.S.;Baskaran, S.;Raghunath, M.
    • Advances in Computational Design
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    • v.4 no.4
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    • pp.367-379
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    • 2019
  • Multiple Inputs and Multiple Outputs (MIMO) Fuzzy logic model is developed to predict the engine performance and emission characteristics of pongamia pinnata biodiesel with hydrogen injection. Engine performance and emission characteristics such as brake thermal efficiency (BTE), brake specific energy consumption (BSEC), hydrocarbon (HC), carbon monoxide (CO), carbon dioxide ($CO_2$) and nitrous oxides ($NO_X$) were considered. Experimental investigations were carried out by using four stroke single cylinder constant speed compression ignition engine with the rated power of 5.2 kW at variable load conditions. The performance and emission characteristics are measured using an Exhaust gas analyzer, smoke meter, piezoelectric pressure transducer and crank angle encoder for different fuel blends (Diesel, B10, B20 and B30) and engine load conditions. Fuzzy logic model uses triangular and trapezoidal membership function because of its higher predictive accuracy to predict the engine performance and emission characteristics. Computational results clearly demonstrate that, the proposed fuzzy model has produced fewer deviations and has exhibited higher predictive accuracy with acceptable determination correlation coefficients of 0.99136 to 1 with experimental values. The developed fuzzy logic model has produced good correlation between the fuzzy predicted and experimental values. So it is found to be useful for predicting the engine performance and emission characteristics with limited number of available data.

Properties of the oxynitride films prepared by reoxidation of thermal oxide in $N_2O$ ($N_2O$ 가스에서 열산화막의 재산화에 의해 형성된 oxynitride막의 특성)

  • Bae, Sung-Sig;Lee, Cheol-In;Choi, Hyun-Sik;Seo, Yong-Jin;Kim, Tae-Hyung;Kim, Chang-Il;Chang, Eui-Goo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1993.05a
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    • pp.39-43
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    • 1993
  • Electricial characteristics of gate dielectrics prepared by reoxidation of thermal $SiO_2$ in nitrous oxide gas have been investigated. 10 and 19nm-thick oxides were reoxidized at temperatures of $900-1000^{\circ}C$ for 10-60 min in $N_2O$ ambient. As reoxidation proceeds, it is shown that nitrogen concentration at $Si/SiO_2$ interface increases gradually through the AES analysis. Nitrogen pile-up at $Si/SiO_2$ interface acts as a oxidant diffusion barrier that reduces the oxidation rate significantly. And it not only strengthen oxynitride structure at the interface but improve the gate dielectric qualities. Reliabilities of oxynitride films are conformed by the breakdown distributions and constant current stress technique. Therefore, the oxynitride films made by this process show a good promise for future ULSI applications.

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