• 한국수소및신에너지학회논문집
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• 제14권3호
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• pp.268-275
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• 2003

The water-splitting process by the metal oxides using solar heat is one of the hydrogen production method. The hydrogen production process using the metal oxides (NiFe2O4/NiAl2O4,CoFe2O4/CoAl2O4, CoMnNiFerrite, CoMnSnFerrite, CoMnZnFerrite, CoSnZnFerrite) was carried out by two steps. The first step was carried out by the CH4-reduction to increase activation of metal oxides at operation temperature. And then, it was carried out the water-splitting reaction using the water at operation temperature for the second step. Hydrogen was produced in this step. The production rates of H2 were 110, 160, 72, 29, 17, $21m{\ell}/hr{\cdot}g-_{Metal\;Oxide}$ for NiFe2O4/NiAl2O4, CoFe2O4/CoAl2O4, CoMnNiFerrite, CoMnSnFerrite, CoMnZnFerrite, CoSnZnFerrite respectively in the second step. CoFe2O4/CoAl2O4 had higher H2 production rate than the other metal oxides.

• 한국토양비료학회지
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• 제43권6호
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• pp.904-910
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• 2010

고추생산체계에 대한 탄소성적을 평가하기 위하여 노지재배 (건고추)와 시설재배 (풋고추)로 구분하여 LCI database 구축하고 전과정 영향평가를 통한 잠재적 환경영향을 평가하였다. LCI 구축을 위한 영농 투입량과 배출물 산정결과 고추 1 kg 생산의 비료 사용량은 노지재배가 2.55E+00 kg $kg^{-1}$ redpepper로 시설재배의 7.74E-01 kg $kg^{-1}$ greenpepper 보다 많았다. 농약 투입은 노지재배와 시설재배가 각각 5.38E-03 kg $kg^{-1}$ redpepper, 2.98E-04 kg $kg^{-1}$ greenpepper으로 노지재배에서의 농약투입량이 훨씬 높았다. 고추생산 중 대기로 배출된 $CO_2$, $CH_4$, $N_2O$의 합은 노지고추가 5.84E-01 kg $kg^{-1}$ redpepper, 2.81E+00 greenpepper로 시설고추가 높았다. 고추 생산체계에 대한 탄소원단위성적 산정결과 노지재배가 4.13E+00 kg $CO_2$-eq. $kg^{-1}$ redpepper, 시설재배 풋고추가 4.70E+00 kg $CO_2$-eq. $kg^{-1}$ greenpepper 였다. 시설재배 (풋고추)는 $CO_2$발생량이 많았고, 노지재배 (건고추)는 $CH_4$와 $N_2O$ 발생량이 많았다. 전과정 영향평가 결과 GWP의 특성화값은 노지재배가 4.13E+00 kg $CO_2$-eq. $kg^{-1}$, 시설재배가 4.70E+00 kg $CO_2$-eq. $kg^{-1}$이었고, GWP범주에 대한 기여도는 노지재배가 약 52%, 시설재배 약 48%로 거의 비슷하였다.

• Biomolecules & Therapeutics
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• 제29권3호
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• pp.273-281
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• 2021

Severe acute respiratory syndrome CoV-2 (SARS-CoV-2) is responsible for the current coronavirus disease 2019 (COVID-19) pandemic. Signaling pathways that are essential for virus production have potential as therapeutic targets against COVID-19. In this study, we investigated cellular responses in two cell lines, Vero and Calu-3, upon SARS-CoV-2 infection and evaluated the effects of pathway-specific inhibitors on virus production. SARS-CoV-2 infection induced dephosphorylation of STAT1 and STAT3, high virus production, and apoptosis in Vero cells. However, in Calu-3 cells, SARS-CoV-2 infection induced long-lasting phosphorylation of STAT1 and STAT3, low virus production, and no prominent apoptosis. Inhibitors that target STAT3 phosphorylation and dimerization reduced SARS-CoV-2 production in Calu-3 cells, but not in Vero cells. These results suggest a necessity to evaluate cellular consequences upon SARS-CoV-2 infection using various model cell lines to find out more appropriate cells recapitulating relevant responses to SARS-CoV-2 infection in vitro.

• 에너지공학
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• 제13권1호
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• pp.1-11
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• 2004

가스화기술은 전세계적으로 수소에너지 사회로 진입하는 과정에서 필요한 대량수소 공급체계를 구축하는데 중단기적으로 필요한 기술이다. 장기적으로는 풍력이나 태양광과 같은 순수한 재생가능에너지에 기반한 수소공급 체계로 발전될 것이나, 향후 10-20년간 대량수순 제조가 필요하다면 경제성이 있는 기술을 $CO_2$ 발생이 최소화되면서 효율도 높은 기술로 발전시켜 적용하는 방향으로 진행될 것이다. 특히, 국내에서는 천연가스, 석탄, 중질잔사유, 폐기물, 바이오매스 등의 원료로부터 출발한 수소제조가 경제적인 측면에서 유리하므로 최소한 중단기적으로는 활용될 것으로 보인다 수소에너지 이슈가 부각되는 배경중의 하나가 기후변화협약에 대응한 $CO_2$저감의 필요성이므로, 이들 중단기적으로 활용될 원료들의 수소제조기술들은 반드시 $CO_2$저감이 가능한 기술로서 개발되어야 한다.

• 미생물학회지
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• 제46권1호
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• pp.46-51
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• 2010

Coenzyme Q10 (CoQ10)은 전자전달계에 필수적인 요소로 질병치료 및 완화에 도움이 되어 산업 의학적으로 그 활용도가 넓어지고 있다. 본 연구에서는 새로운 CoQ10 생산균주를 선별하기 위하여 quinone 분석 결과 CoQ10을 함유하는 것으로 확인된 8종 미생물의 생장특성과 CoQ10 생산능을 1차 조사하여, 세균류인 Paracoccus denitrificans KCTC 2530과 Asaia siamensis KCTC 12914를 대량배양을 통한 CoQ10 생산에 유리한 특성을 갖는 균주로 선별하였다. 이들 세균류의 생장 및 CoQ10 생산의 최적조건을 플라스크배양으로 조사한 결과, M81 배지를 기반으로 하여 탄소원으로는 4% fructose, 질소원으로는 2% yeast extract가 가장 좋은 것으로 조사되었으며, 배양온도는 $30^{\circ}C$, 배지의 최적 pH는 P. denitrificans KCTC 2530의 경우 pH 6.0, A. siamensis KCTC 12914의 경우 pH 8.0으로 조사되었다. 이를 바탕으로 2 L fed-batch culture를 수행한 결과, P. denitrificans KCTC 2530은 1 L 당 $14.34{\pm}0.473$ mg, A. siamensis KCTC 12914는 $12.53{\pm}0.231$ mg의 CoQ10을 생산하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.169-169
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• 2022

Over the past 100 years, the global average temperature has risen by 0.75 ℃. The Korean Peninsula has risen by 1.8 ℃, more than twice the global average. According to the RCP 8.5 scenario, the CO₂ concentration in 2100 will be 940 ppm, about twice as high as current. The National Institute of Crop Science(NICS) is using the SPAR (Soil-Plant Atmosphere Research) facility that can precisely control the environment, such as temperature, humidity, and CO₂. A Python-based colony photosynthesis algorithm has been developed, and the carbon and nitrogen absorption rate of rice is evaluated by setting climate change conditions. In this experiment, Oryza Sativa cv. Shindongjin were planted at the SPAR facility on June 10 and cultivated according to the standard cultivation method. The temperature and CO₂ settings are high temperature and high CO₂ (current temperature+4.7℃ temperature+4.7℃·CO₂ 800ppm), high temperature single condition (current temperature+4.7℃·CO₂ 400ppm) according to the RCP8.5 scenario, Current climate is set as (current temperature·CO₂400ppm). For colony photosynthesis measurement, a LI-820 CO₂ sensor was installed in each chamber for setting the CO₂ concentration and for measuring photosynthesis, respectively. The colony photosynthetic rate in the booting stage was greatest in a high temperature and CO₂ environment, and the higher the nitrogen fertilization level, the higher the colony photosynthetic rate tends to be. The amount of photosynthesis tended to decrease under high temperature. In the high temperature and high CO₂ environment, seed yields, the number of an ear, and 1000 seed weights tended to decrease compared to the current climate. The number of an ear also decreased under the high temperature. But yield tended to increase a little bit under the high temperature and high CO₂ condition than under the high temperature. In addition, In addition to this study, it seems necessary to comprehensively consider the relationship between colony photosynthetic ability, metabolite reaction, and rice yield according to climate change.

• 상하수도학회지
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• 제11권2호
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• pp.50-64
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• 1997

Life cycle assessment (LCA) on total sewage sludge treatment system from thickening to incineration and melting was performed for estimating global environmental impact as $CO_2$. In general, the life cycles of actual treatment facilities consist of construction, operation and dismantlement. In this study, the amount of $CO_2$ produced from both whole and each life cycle step of currently used unit sludge treatment processes were calculated by inventory analysis. In addition, in the all processes investigated in this study, individual $CO_2$ production unit (CPU), i.e. total produced $CO_2$ by treating a unit weight of sludge was also calculated. By using the CPU matrix of the unit processes, it was possible to simulate the $CO_2$ production for any type of complex-system as well as to trace a dominant cause of $CO_2$ production in each process. Four selected alternatives examined here, each involve the same disposal way but differ substantially in the $CO_2$ exhaust.

• 전기학회논문지
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• 제59권9호
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• pp.1507-1513
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• 2010

The $CO_2$ emission can be decreased due to freedom of generator maintenance scheduling(GMS). This paper proposes assessment of $CO_2$ emission considering generator maintenance scheduling(GMS) and evaluates effect of the GMS on $CO_2$ emission. And also, this paper assesses the $CO_2$ emission and the probabilistic production cost simulation of nuclear and thermal power generators considering operation of hydro and pumped generator. The minimum reliability criterion level satisfied production cost minimization function model is used in this paper. The practicality and effectiveness of the proposed approach are demonstrated by simulation studies for a real size power system in Korea in 2010.

• Korean Chemical Engineering Research
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• 제46권5호
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• pp.1002-1007
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• 2008

이 논문의 목적은 PEMFC 작동을 위한 플라즈마 개질 시스템의 최적 조건을 연구한 것이다. 플라즈마 개질 반응기는 니켈 촉매 반응기와 동시에 사용하여 수소 생성을 증대하였다. 또한 수성가스 전환 반응기 및 선택적 산화 반응기는 연료전지의 촉매 피독에 영향을 주는 일산화탄소의 농도를 10 ppm 이하로 줄이기 위하여 제작되었다. 플라즈마 개질기에서 최대 수소생산 조건은 S/C 비 3.2, 메탄 2.0 L/min, 촉매반응기 온도는 $700{\pm}5^{\circ}C$ 그리고 입력전력 900 W이다. 이때의 합성가스의 농도는 $H_2$ 70.2%, CO 7.5%, $CO_2$ 16.2%, $CH_4$ 1.8% 이다. 수소 수율, 수소 선택도 그리고 메탄 전환율는 각각 56.8%, 38.1%, 92.2%이다. 에너지 효율과 에너지 요구량은 37.0%, 183.6 kJ/mol 이다. 추가적으로 $CO_2/CH_4$ 비 실험을 진행하였다. 또한 수성가스 전환 반응기는 플라즈마 개질 반응기의 최적조건으로 실험을 진행하였으며, 출구 농도는 $H_2$ 68.0%, CO 337 ppm, $CO_2$ 24.0%, $CH_4$ 2.2%, $C_2H_4$ 0.4%, $C_2H_6$ 4.1% 이다. 이때의 선택적 산화 반응기의 실험결과는 $H_2$ 51.9%, CO 0%, $CO_2$ 17.3%를 나타냈다.

• 한국농공학회논문집
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• 제56권1호
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• pp.61-70
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• 2014

South Korea is under pressure to reduce $CO_2$ emissions because of expanding request for reducing $CO_2$ emissions. In many industry sectors, $CO_2$ emissions were analyzed to reduce $CO_2$ emissions. But little effort in researching agricultural sector has been undertaken because it is recognized as environmentally friendly industry. The object of this research is to estimate $CO_2$ emissions of crops and analysis on correlation between $CO_2$ emissions and production, acreage of crops. In this study, environmental input-output analysis was used to estimate $CO_2$ emissions of agricultural sector and spearman correlation coefficient was used to analysis on correlation between $CO_2$ emissions and statics like production and acreage. As a result, rice, barley, pulses and horticultural specialities had correlation with acreage and correlation coefficients of these crops were 0.800~0.933. Regression equations about $CO_2$ emissions and acreage of rice, barley, pulses and horticultural specialities was made and $R^2$ of these equations were 0.615~0.929. Using equations, $CO_2$ emissions of rice, barley, pulses and horticultural specialities can be estimated with acreage.