• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2009년도 제33회 추계학술대회논문집
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• pp.58-61
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• 2009

추진제로써 아산화질소를 활용하기 위해 아산화질소의 촉매 분해 특성에 대한 연구를 수행하였다. 아산화질소를 분해하기 위해 Ru와 Pt 촉매를 $Al_2O_3$ 지지체에 함침법을 이용하여 담지하였고, 관형 반응기를 사용하여 GHSV와 반응온도에 따른 아산화질소의 전환율을 측정하였다. GHSV는 낮을수록, 반응온도는 높을수록 전환율이 높았고, Ru/$Al_2O_3$ 촉매가 Pt/$Al_2O_3$ 촉매보다 우수한 성능을 보였다.

• Journal of Dental Anesthesia and Pain Medicine
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• 제18권2호
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• pp.71-78
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• 2018

The first clinical application of nitrous oxide ($N_2O$) was in 1844, by an American dentist named Horace Wells who used it to control pain during tooth extraction. Since then, $N_2O$ has shared a 170-year history with modern dental anesthesia. $N_2O$, an odorless and colorless gas, is very appealing as a sedative owing to its anxiolytic, analgesic, and amnestic properties, rapid onset and recovery, and, in particular, needle-free application. Numerous studies have reported that $N_2O$ can be used safely and effectively as a procedural sedation and analgesia (PSA) agent. However, $N_2O$ can lead to the irreversible inactivation of vitamin B12, which is essential for humans; although rare, this can be fatal in some patients.

• Journal of Advanced Marine Engineering and Technology
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• 제38권9호
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• pp.1051-1056
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• 2014

아산화질소($N_2O$, Nitrous Oxide)는 박테리아의 물질대사와 같은 생물학적인 활동에 의하여 자연적으로 발생한다. 하지만, 최근의 대기 중 $N_2O$는 산업의 성장과 같은 인간의 활동에 의하여 증가되어져 왔다. 이 중에 대기 중의 $N_2O$농도를 증가시키는 요인들 중에 하나는 선박용 연료 연소로부터 발생하는 $N_2O$이다. 현재 해상 운송은 국제 물류의 99퍼센트 이상을 담당하고 있고, 선박척수는 물동량의 증가와 함께 증가하고 있다. 따라서, 본 연구에서는 4-행정 선박용 디젤엔진을 사용하여 다른 성분 농도들을 포함하는 연료의 연소가 $N_2O$ 배출률에 미치는 영향에 대하여 실험적인 조사를 실시하였다. 또한, 연소실 내의 연료 연소 패턴이 $N_2O$ 배출률에 미치는 영향에 대하여 평가하였다.

• Journal of Microbiology and Biotechnology
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• 제23권1호
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• pp.99-105
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• 2013

In this study, nitrous oxide ($N_2O$) emission was compared between the operations of two different sequencing batch reactors, conventional sequencing batch reactor (CNVSBR) and simultaneous nitrification and denitrification sequencing batch reactor (SND-SBR), using synthetic wastewater. The CNV-SBR consisted of anoxic (denitrification) and aerobic phases, whereas the SND-SBR consisted of a microaerobic (low dissolved oxygen concentration) phase, which was achieved by intermittent aeration for simultaneous nitrification and denitrification. The CNV-SBR emitted 3.9 mg of $N_2O$-N in the denitrification phase and 1.6 mg of $N_2O$-N in the nitrification phase, resulting in a total emission of 5.5mg from 432mg of $NH_4^+$-N input. In contrast, the SND-SBR emitted 26.2mg of $N_2O$-N under the microaerobic condition, which was about 5 times higher than the emission obtained with the CNV-SBR at the same $NH_4^+$-N input. From the $N_2O$ yield based on $NH_4^+$-N input, the microaerobic condition produced the highest yield (6.1%), followed by the anoxic (0.9%) and aerobic (0.4%) conditions. It is thought that an appropriate dissolved oxygen level is critical for reducing $N_2O$ emission during nitrification and denitrification at wastewater treatment plants.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권2호
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• pp.137-142
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• 1999

One of the most important parameters required to model the absorption of CO2 into aqueous alkanolamine solutions is physical solubility. However, since CO2 reacts in amine solutions, its physical solubility cannot be measured directly. As a result, a nonreacting gas which is similar to CO2 has to be used such as N2O. The solubility of nitrous oxide (N2O) in aqueous solutions of 0wt%-50wt% MDEA, 0wt%-30wt% DEA, and 50wt % total amine with DEA/MDEA molar ratios of 0.05, 0.25, 0.5 and 0.67 was measured using a modified Zipperclave reactor over a temperature range of 293-353 K with near atmospheric partial pressures of N2O. the solubility data from this work were K with near atmospheric partial pressures of N2O. The solubility data from this work were found to be in good agreement with previously reported data where available.

• 동력기계공학회지
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• 제18권6호
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• pp.106-112
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• 2014

The diesel engine, which has high compression ratio than other heat engines, has been using as the main power source of marine transport. Especially, since marine diesel engines offer better specific fuel consumption (SFC), it is environment-friendly compared to those used in other industries. However, attentio should be focused on emissions such as nitrous oxide ($N_2O$) which is generated from combustion of low-grade fuels. Because $N_2O$ in the atmosphere is very stable, the global warming potential (GWP) of $N_2O$ is 310 times as large as that of $CO_2$, and it becomes a source of secondary contamination after photo-degradation in the stratosphere. It has been hitherto noted on the $N_2O$ exhaust characteristics from stationary power plants and land transportations, but reports on $N_2O$ emission from the marine diesel engine are very limited. In this experimental study, a author investigated $N_2O$ emission characteristics by using changed diesel fuel components of nitrogen and sulfur concentration, assessed on the factors which affect $N_2O$ generation in combustion. The experimental results showed that $N_2O$ emission exhibited increasement with increasing of sulfur concentration in fuel. However, all kinds of nitrogen component additives used in experiment could not change $N_2O$ emission.

• 한국수자원학회논문집
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• 제42권8호
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• pp.631-641
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• 2009

본 연구는 부영양화되어 있는 하구감조역에서의 $N_2O$생성과 거동을 파악하는 것을 목적으로 도시역에서의 N2O발생에 착안하여 그 중에서도 인위적 임팩트가 크다고 판단되는 하수처리수 생활폐수 등이 유입되는 도시하천감조역을 대상으로 현지 정점조사를 실시하여 수역의 사계절에 걸친 각 질소성분의 농도변화와 flux를 상세히 파악하고 저질간극수 중의 연직분포를 측정하였다. 그 결과, 완혼합이고 염수쐐기설(楔)가 형성되는 Tatara천(川)에서 하수처리수는 해수의 혼합형태의 영향을 크게 받고 고농도수괴(水塊)로서 표층을 이동하고 있으며, 이 수역의 질소변환기구 및 $N_2O$생성과정에 큰 영향을 미치고 있는 것이 밝혀졌다. 이 수역에서 관측된 $N_2O$농도는 1.8-20.9 $\mu M$로서 대기중의 포화농도와 담수중의 포화농도를 고려하면 항상 포화농도상태이며, 주발생원은 수역저토였다. 저질간극수 중의 각 질소성분의 농도분포는 호소와 인근해역에서의 분포와는 달리 분자확산 이외의 수송경로가 있다는 것이 시사되었다.

• 한국항공우주학회지
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• 제38권4호
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• pp.369-375
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• 2010

추진제로써 아산화질소를 활용하기 위해 아산화질소의 촉매 분해 특성에 대한 연구를 수행하였다. 아산화질소 분해 반응을 위한 고성능 촉매를 선정하기 위해 Pt, Ir, Ru 촉매를 합성하였다. 촉매 합성을 위해 각각의 촉매 전구체를 함침법을 이용하여 $Al_2O_3$ 지지체에 담지하였다. 제조된 촉매는 관형 반응기를 사용하여 공간속도와 반응온도에 따른 $N_2O$ 전환율을 가스 분석을 통해 측정하였다. 또한 촉매 내구성을 판단하기 위해 $800^{\circ}C$에서 2시간 동안 반응한 후 촉매 유실량을 측정하였다. $N_2O$ 전환율은 공간속도가 낮을수록 반응온도가 높을수록 높았고, Ru/$Al_2O_3$ 촉매가 낮은 온도에서 가장 높은 $N_2O$ 전환율을 보였고 내구성도 가장 우수하였다.

• The Korean Journal of Pain
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• 제12권1호
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• pp.43-47
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• 1999

Backgroud: Systemic administration of opioid can prolong the duration of epidural anesthesia. The authors examined the effect of nitrous oxide ($N_2O$) on the level of sensory block induced by epidural lidocaine. Methods: Twenty minutes after epidural injection of 2% lidocaine (below 70 years : 20 ml, 70 years and above : 15 ml), the level of sensory block was assessed (2nd stage). Patients were randomly assigned to receive either medical air (control group, n=15) or 50% $N_2O$ in oxygen ($N_2O$ group, n=15) for 10 minutes, the level of block was reassessed (3rd stage). Pateints were given room air (control group) or 100% oxygen for 5 minutes and room air for 5 minutes ($N_2O$ group), and the level of block was reassessed (4th stage). Results: At the 3rd stage, $N_2O$ group showed 4.3 cm cephalad increase in the level of sensory block (p=0.005), but control group revealed 1.43 cm regression. After discontinuation of gas, the level of block regressed in both group (p=0.000). At the 4th stage, $N_2O$ group revealed 3.5 cm cephalad increase (p=0.048) and control group 1.97 cm regression (p=0.001) as compared with the 2nd stage. Conclusions: The level of sensory block induced by epidural lidocaine was significantly increased cephalad by concommitant use of 50% $N_2O$ for 10 minutes.

• 한국토양비료학회지
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• 제47권5호
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• pp.368-373
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• 2014

Ammonia loss from urea significantly hinders efficient use of urea in agriculture. The level of nitrous oxide ($N_2O$) a long-lived greenhouse gas in atmosphere has increased mainly due to anthropogenic source, especially application of nitrogen fertilizers. There are reports in the literature showing that the addition of zeolite to N sources can improve the nitrogen use efficiency. This study was conducted to evaluate nitrous oxide ($N_2O$) and ammonia ($NH_3$) emission by mixed treatment of urea and zeolite in upland crop field. Urea fertilizer and zeolite were applied at different rates to study their effect on $N_2O$ emission during red pepper cultivation in upland soils. The $N_2O$ gas was collected by static closed chamber method and measured by gas chromatography. Ammonia concentration was analyzed by closed-dynamic air flow system method. The total $N_2O$ flux increased in proportion to the level of N application. Emission of $N_2O$ from the field increased from the plots applied with urea-zeolite mixture compared to urea alone. But urea-zeolite mixture treatment reduced about 30% of $NH_3$-N volatilization amounts. These results showed that the application of urea and zeolite mixture had a positive influence on reduction of $NH_3$ volatilization, but led to the increase in $N_2O$ emission in upland soils.