• Applied Biological Chemistry
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• 제14권1호
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• pp.51-57
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• 1971

$CO_2$의 흡수능력(吸收能力)을 비교(比較)하기 위(爲)하여 습윤연소실험(濕潤燃燒實驗)에 있어서 Phenyl Ethylamine과 Hyamine Base를 사용(使用)하였다. 알려지고 있는 간장지질(肝藏脂質)과 균일(均一)하게 혼합(混合)된 팔미딘산-$C^{14}$을 유산(硫酸)과 인산(燐酸)으로 산화(酸化)하였다. 생성(生成)된 $CO_2$를 가느다란 비닐관(管)을 통하여 공시(供試)아민제(劑)에 포착(捕捉)시켰다. $CO_2$를 흡수(吸收)한 아민 제(劑)들을 Diotal Scintillator와 혼합(混合)하고 Liquid Scintillation Counter에 의(依)하여 그 방사능(放射能)을 측정(測定)하였다. 공시(供試)한 2종(種)아민의 계측효율(計測效率)은 $50{\sim}60%$이 었으며 방사능회수율(放射能回收率)은 거의 100%이었다. 그러나 Phenyl Ethylamine에 의(依)한 $CO_2$흡수량(吸收量)이 Hyamine Base의 그것에 비(比)하여 약(約) 2배(倍)가 되었으며 취급(取扱)하기도 용이(容易)하고 대금(代金)도 싸기 때문에 $CO_2$ 흡수제(吸收劑)로서는 Phenyl Ethylamine을 사용(使用)함이 좋을 것이다. 한편 돼지의 간장실험(肝藏實驗)에 있어서 지질(脂質)을 $CO_2$로 변화(變化)시켜 $C^{14}$의 방사능(放射能)을 측정(測定)하는 것이 지질(脂質)을 그대로 계측(計測)하는 것보다 계측효율(計測效率)이 더 증가(增加)되지 않음이 밝혀졌다.

• 한국추진공학회지
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• 제22권1호
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• pp.36-44
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• 2018

고체 로켓 추진기관 노즐의 내열재로 사용되는 탄소/페놀릭 복합재료의 열반응 수치해석을 수행하였다. 본 논문에서 탄소/페놀릭 재료의 열반응 해석은 (1) 로켓 노즐벽에서 대류열전달계수를 구하기 위한 연소가스의 경계층 적분방정식 수치해석과 (2) 삭마두께, 숯깊이 및 온도를 계산하기 위한 탄소/페놀릭의 열반응(열분해, 삭마)을 고려한 1차원 열전도 해석으로 구성된다. 시험결과와 해석결과를 비교 분석하였으며, 목삽입재 좌우 인접 부위를 제외하고 잘 일치하는 것을 확인 할 수 있었다.

• 한국산림과학회지
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• 제95권4호
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• pp.405-414
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• 2006

우리나라는 제2차 공약기간(2013~2017년)부터 온실가스 의무감축국에 포함될 것으로 전망된다. 본 연구에서는 향후 협상에 대비하여 현재 국제적으로 진행되고 있는 목제품 탄소계정 논의 동향 및 방법별 특정을 살펴보고, 이에 따른 국내 탄소 배출량에 미치는 영향을 분석하였다. 그 결과, 목제품 탄소계정 방법의 가장 큰 특정은 현행 IPCC 기본 접근법을 제외하고 목재 무역 규모에 따라 탄소 배출량에 큰 차이가 발생한다는 것이다. 축적변화 접근법은 국내에 존재하는 모든 목제품이 탄소축적 변화량으로 계정되기 때문에 순 목재수입국에 유리한 방법이다. 생산 접근법은 국내에서 생산된 목제품만을 대상으로 탄소축적 변화량을 평가하고 수입 목제품은 계정되지 않는다. 대기유출입 접근법은 목제품의 사용으로 인해 최종적으로 분해 연소가 발생하는 장소가 탄소 배출지로 평가되기 때문에 순 목재 수출국에 유리한 방법이다. 한편, 우리나라의 목제품 탄소축적 변화량을 추정한 결과, 2004년 현재 축적변화 접근법이 1.567 Tg C, 생산 접근법이 0.581 Tg C, 대기유출입 접근법이 -1.425 Tg C로, 순 목재수입국인 우리나라는 축적변화 접근법이 국내 탄소배출량 감소에 가장 유리한 방법인 반면, 대기유출입 접근법이 가장 불리한 방법이었다.

• Journal of Ecology and Environment
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• 제41권12호
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• pp.336-344
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• 2017

Background: Because of climate change, interest in the development of carbon pools has increased. In agricultural ecosystems, which can be more intensively managed than forests, measures to control carbon dioxide ($CO_2$) emission and absorption levels can be applied relatively easily. However, crop residues may be released into the atmosphere by decomposition or combustion. If we can develop scientific management techniques that enable these residues to be stocked on farmland, then it would be possible to convert farmlands from carbon emission sources to carbon pools. We analyzed and investigated soil respiration (Rs) rate characteristics according to input of carbonized residue of red peppers (Capsicum annuum L.), a widely grown crop in Korea, as a technique for increasing farmland carbon stock. Results: Rs rate in the carbonized biomass (CB) section was $226.7mg\;CO_2\;m^{-2}h^{-1}$, which was 18.1% lower than the $276.9mg\;CO_2\;m^{-2}h^{-1}$ from the red pepper residue biomass (RB) section. The Rs rate of the control was $184.1mg\;CO_2\;m^{-2}h^{-1}$. In the following year, Rs in the CB section was $204.0mg\;CO_2\;m{-2}h^{-1}$, which was 38.2% lower than the $330.1mg\;CO_2\;m^{-2}h^{-1}$ from the RB section; the control emitted $198.6mg\;CO_2\;m^{-2}h^{-1}$. Correlation between Rs and soil temperature ((Ts) at a depth of 5 cm) was $R^2=0.51$ in the RB section, which was higher than the other experimental sections. A comparison of annual decomposition rates between RB and CB showed a large difference, 41.4 and 9.7%, respectively. The results showed that carbonization of red pepper residues reduced the rates of decomposition and Rs. Conclusions: The present study confirmed that the Rs rate can be reduced by carbonization of residue biomass and putting it in the soil and that the Rs rate and Ts (5 cm) were positively correlated. Based on the results, it was determined that approximately $1.2t\;C\;ha^{-1}$ were sequestered in the soil in the first year and $3.0t\;C\;ha^{-1}$ were stored the following year. Therefore, approximately $1.5t\;C\;ha^{-1}year^{-1}$ are expected to be stocked in the soil, making it possible to develop farmlands into carbon pools.

• 한국토양비료학회지
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• 제47권6호
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• pp.457-463
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• 2014

This study was carried out to find out major factors to mitigate carbon emission using Life Cycle Assessment (LCA). System boundary of LCA was confined from sowing to packaging during vegetable production. Input amount of agri-materials was calculated on 2007 Income reference of white radish, chinese cabbage and chive produced at open field and film house published by Rural Development Administration. Domestic data and Ecoinvent data were used for emission factors of each agri-material based on the 1996 IPCC guideline. Carbon footprint of white radish was 0.19 kg $CO_2kg^{-1}$ at open fields, 0.133 kg $CO_2kg^{-1}$ at film house, that of chinese cabbage was 0.22 kg $CO_2kg^{-1}$ at open fields, 0.19 kg $CO_2kg^{-1}$ at film house, and that of chive was 0.66 kg $CO_2kg^{-1}$ at open fields and 1.04 kg $CO_2kg^{-1}$ at film house. The high carbon footprint of chive was related to lower vegetable production and higher fuel usage as compared to white radish and Chinese cabbage. The mean proportion of carbon emission was 35.7% during the manufacturing byproduct fertilizer; white radish at open fields was 50.6%, white radish at film house 13.1%, Chinese cabbage at outdoor 38.4%, Chinese cabbage at film house 34.0%, chive at outdoor 50.6%, and chive at film house 36.0%. Carbon emission, on average, for the step of manufacturing and combustion accounted for 16.1% of the total emission; white radish at open fields was 4.3%, white radish at film house 15.6%, Chinese cabbage at open fields 6.9%, Chinese cabbage at film house 19.0%, chive at open fields 12.5%, and chive at film house 29.1%. On the while, mean proportion of carbon footprint for the step of $N_2O$ emission was 29.2%; white radish at open fields was 39.2%, white radish at film house 41.9%, Chinese cabbage at open fields 34.4%, Chinese cabbage at film house 23.1%, chive at open fields 28.8%, and chive at film house 17.1%. Fertilizer was the primary factor and fuel was the secondary factor for carbon emission among the vegetables of this study. It was suggested to use Heug-To-Ram web-service system, http://soil.rda.go.kr, for the scientific fertilization based on soil testing, and for increase of energy efficiency to produce low carbon vegetable.

• 한국대기환경학회지
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• 제30권4호
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• pp.319-326
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• 2014

Exhaust gas emitted as a result of the incomplete combustion of biomass in charcoal kilns includes odor compounds as well as other air pollutants such as particulate matters, sulfur and nitrogen oxides, and carbon monoxide. A number of offensive odor compounds affect quality of life. In this study, odor emissions were investigated from biomass burning in a pilot-scale charcoal kiln and a commercial-scale kiln. Complex odor from emission source reached up to 10,000 dilutions to threshold during the study period. Combustion fume was found to contain reduced sulfur compounds, aldehydes, and volatile organic compounds. Hydrogen sulfide and methyl mercaptan were the major odorants which highly contributed to the offensive odor.

• 한국자동차공학회논문집
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• 제15권6호
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• pp.102-107
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• 2007

A fast response $CO_2$ ($fCO_2$) analyzer for real-time measurement of carbon dioxide concentration during transient states of internal combustion engines has been developed. This analyzer uses non-dispersive infrared absorption (NDIR) technique for measuring $CO_2$ concentration and Kalman filter for removing noise components from output signals. The analyzer has good linearity, repeatability and drift with a response time of 11 ms; it is sufficiently fast to detect $CO_2$ concentration during transient states of internal combustion engines. The $fCO_2$ analyzer was used to measure transient $CO_2$ concentration of exhaust gas of the SI engine with a standard gas analyzer, and the signal of the $fCO_2$ analyzer was compared to that of the standard gas analyzer. The two concentrations were well matched during the steady state, and the $fCO_2$ analyzer could measure the variations of $CO_2$ concentration during the transient state.

• International Journal of Safety
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• 제4권2호
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• pp.24-29
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• 2005

An experimental study was presented for extinguishing characteristics of liquid fuel fire by water mist($Dv_{0.99}{\leq}200{\mu}m$) containing potassium acetate and sodium acetate trihydrate. To evaluate the extinguishing performance of water mist containing additives, the evaporation characteristics of a water droplet on a heated surface was examined. The evaporation process was recorded by a charge-coupled-device camera. Also, small-scale extinguishing tests were conducted for n-heptane pool fire in ventilated space. During the experiments, flame temperatures were measured, and concentrations of oxygen and carbon monoxide were analyzed by a combustion gas analyzer. The average evaporation rate of water droplet containing additives was lower than that of pure water at a given surface temperature and decreased with the concentration increase due to the precipitation of salt in the liquid-film and change of surface tension. In case of using additives, the fire extinguishing times was shorter than that of pure water at a given discharge pressure and it was because the momentum of a water droplet containing additives was increased. And also dissociated metal atoms, potassium or sodium, were reacted as a scavenger of the major radical species OH, H which were generated for combustion process. Moreover, at a high pressure of 4 MPa, the fire was extinguished through blowing effect as well as primary extinguishing mechanisms.

• 한국농공학회논문집
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• 제48권3호
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• pp.63-71
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• 2006

A downdraft gasifier was made of stainless steel for biomass gasification. Internal reactor had a 300 mm diameter and 8 air intakes. Three thermocouples were installed to measure the temperature inside the reactor. Three different biomass fuels were provided in the experiments to find out the effects of fuel conditions on gasification processes; charcoals, woodchips, and mixture of woodchip and charcoals. Two different experiments were conducted fer charcoal experiments, small and larger sizes of charcoal fuels. It took about 10 minutes after ignition to generate combustible producer gas when charcoal was f9d, but 20 or more minutes for woodchips. When the gasification was stabilized, the highest temperature was observed just below the combustion zone. The air flow rate for woodchip experiment was provided at 25% of a stoichiometric requirement of combustion, which was within the range of typical air flow rate fer woody biomass gasification. Carbon monoxide concentrations were also within the values reported in the previous studies, ranging 20 to 30% depending on fuel types. It could be seen that fuel size and heating value were very important parameters in biomass gasification. These parameters should be taken into account in operating and designing biomass gasifiers.

• 한국자동차공학회논문집
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• 제11권1호
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• pp.72-78
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• 2003

Recently, lots of researchers have been attracted to develope various alternative fuels and to use renewable fuels as a solution of environmental problems from automobile. The use of biodiesel fuel is an effective way of substituting diesel fuel in the long nun. It is a domestically produced, renewable fuel that can be manufactured from vegetable oils, used vegetable oils, or animal fats. In this study, the usability of biodiesel fuel derived from rice ban oil, one of the oxygenated fuels as an alternative fuel for diesel engines was investigated in IDI diesel engine. Emissions were characterized with neat biodiesel fuel and with a blend of biodiesel fuel and conventional diesel fuel. Since the biodiesel fuel includes oxygen of about 11%, it could influence the combustion process strongly. So, the use of biodiesel fuel resulted in lower emissions of carbon monoxide and smoke emissions with some increase in emissions of oxides of nitrogen. It is concluded that biodiesel fuel can be utilized effectively as a renewable fuel for IDI diesel engine.