• Journal of Korean Society of Environmental Engineers
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• 제29권5호
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• pp.528-532
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• 2007

The generation of high-purity hydrogen from hydrocarbon fuels is essential for efficient operation of fuel cell. In general, most feasible strategies to generate hydrogen from hydrocarbon fuels consist of a reforming step to generate a mixture of $H_2$, CO, $CO_2$ and $H_2O$(steam) followed by water gas shift(WGS) and CO clean-up steps. The WGS reaction that shifts CO to $CO_2$ and simultaneously produces another mole of $H_2$ was carried out in a two-stage catalytic conversion process involving a high temperature shift(HTS) and a low temperature shift(LTS). In the WGS operation, gas emerges from the reformer is taken through a high temperature shift catalyst to reduce the CO concentration to about $3\sim4%$ followed to about 0.5% via a low temperature shift catalyst. The WGS reactor was designed and tested in this study to produce hydrogen-rich gas with CO to less than 0.5%.

• Proceedings of the Korean Society of Crop Science Conference
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• 한국작물학회 1987년도 추계 학술대회지
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• pp.12-13
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• 1987

• Proceedings of the Korea Air Pollution Research Association Conference
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• 한국대기환경학회 2001년도 추계학술대회 논문집
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• pp.423-424
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• 2001

플라즈마를 이용한 가스상 오염물질 처리에 대한 연구는 일부 선진국에서 1970년대부터 시작되어 현재는 상용화 연구가 활발히 진행되고 있으며, 국내에서도 1990년대 중반부터 화력발전소에서 배출되는 연소가스 중의 유해성분을 처리하기 위한 연구를 필두로 최근에는 휘발성 유기화합물(VOCs) 분해관련 연구 등 상당한 연구가 수행되고 있다. 저온 플라즈마 공정은 전기적 방전 특성을 이용하므로 스트리머코로나 형성영역인 반응기와 전원공급장치 사이의 기계적ㆍ전기적 매칭(matching)이 중요한 과제이다. (중략)

• KOREAN JOURNAL OF CROP SCIENCE
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• 제34권1호
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• pp.106-112
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• 1989

To investigate varietal differences of anther size, pollen shape, pollen fertility and other agronomic characters under low temperature condition. twenty rice varieties (5 Tongil and 15 Japonica type) were treated at 19$^{\circ}C$ water temperature from booting to heading stage. There was varietal difference of low temperature response which was indicated by the delayed heading, the shortening of culm and panicle length. and the decrease of grain fertility and yield potential resulted from cooling treatment at booting stage. The varieties with low fertility damaged by the low temperature treatment at booting stage showed low pollen density per anther. small or abnormal anthers and pollen, and many sterile pollens. Anther length was correlated significantly with the number of pollens per anther and pollen fertility.

• Clean Technology
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• 제26권4호
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• pp.321-328
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• 2020

This experiment compared V/W/TiO2 and V/Mo/TiO2 catalysts that were used for commercial catalysts. The effects of SCR reactions on low-temperature activity were studied. NH3-TPD, DRIFT, and H2-TPR analysis, alongside O2-on/off experiments, were conducted to identify the effects of NH3 acid sites and oxygen participating in the SCR reaction, which had a significant impact on the NH3-SCR reaction. The effect on activity was analyzed at 250 ℃, a high temperature of reaction activity, and 180 ℃, which showed significant activity degradation. In NH3 involved in the SCR reaction at 250 ℃, B and L acid sites contributed to the reaction. In particular, the B acid site was found to have significantly participated in the reaction and affected the NH3-SCR activity, which was reduced at 180 ℃ to affect the activity degradation. Also, atmospheric oxygen contributed to the SCR reaction, causing the active property to facilitate reaction activity at 250 ℃. However, oxygen did not comprise the reaction at 180 ℃, indicating a drop inactivity. Therefore, the B acid site was reduced, and the activity was judged to be degraded due to failure to share in the reaction and low effects by atmospheric oxygen.

• Korean Journal of Environmental Agriculture
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• 제26권4호
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• pp.325-331
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• 2007

A series of experiments were performed to evaluate effects of lettuce seed treatment with low temperature and dry heat treatment (DHT) on bolting response in the case of spring cultivation. During spring production in greenhouse, bolting response of the plants produced from the treated seeds was faster in the order of low temperature treatment, control and DHT. Plant height was increased 5-10 cm higher by low temperature treatment, but plant growth of some cultivars was inhibited by DHT. Difference on lettuce plant growth between low temperature treatment and DHT was gradually diminished with the lapse of time after transplanting. Fresh weight of plant was not significantly different among all treatments. 'Red Gyeolku' showed very early bolting response and plant height was significantly promoted by low temperature treatment. However, 'Cheongchima' showed low bolting percentage after various seed treatments, so it is considered late-bolting cultivar.

• Analytical Science and Technology
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• 제7권3호
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• pp.321-327
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• 1994

The mild thermal decomposition of 7, 7-dimethyl-1, 2, 3, 4, 5-pentaphenyl-7-silanorbornadiene with excess methyl alcohol proceeds to give 1-methoxydimethylsilyl-1, 2, 3, 4, 6-pentaphenylcyclohexa-2, 5-diene which is colorless needle crystal. The cophotolysis of the solution of 7-silanorbornadiene in the excess ethyl alcohol proceeds with loss of silylenes to give ethoxydimethylsilane which is insertion reaction product of silylene with O-H bond of ethyl alcohol. According to above results, it is presumed that the mechanism of photochemical decomposition and that of mild thermochemical decomposition of 7-silanorbornadiene are different.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제66권1호
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• pp.37-71
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• 2021

Rapeseed is a typical winter crop, and its freezing stress tolerance is a major feature for winter survival. Therefore, it is important to comprehend clearly the physical and molecular mechanisms of rapeseed under freezing stress conditions. This study investigates the physical and transcriptome changes of two rapeseed lines, 'J8634-B-30' and 'EMS26', under cold acclimation and freezing temperature treatments. The proline content of 'J8634-B-30' at 5 ℃ increased 8.7-fold compared to that before treatment, and there was no significant change in that of 'EMS26' RNA-sequencing analysis revealed 5,083 differentially expressed genes (DEGs) of 'J8634-B-30' under cold acclimation condition. Among the genes, 2,784 (54.8%) were up-regulated and 2,299 (45.2%) were down-regulated. The DEGs of 'EMS26' under cold acclimation condition were 5,831 genes, and contained 2,199 up-regulated genes (37.7%) and 3,632 down-regulated genes (62.3%). Among them, only DEGs annotated in the cold response-related signaling pathways were selected, and their expression in the two rapeseed lines was compared. Comparative DEGs analysis indicated that cold response related signaling pathways are proline metabolism and ABA (Abscisic acid) signaling. And ICE (Inducer of CBF expression) - CBF (C-repeat-binding factor) - COR (Cold-regulated) signaling were the significantly differentially expressed transcripts in the two rapeseed lines. The major induced transcripts of 'J8634-B-30' induced P5CS (Δ'-pyrroline-5-carboxylate synthetase), which is related to proline biosynthesis, PYL (pyrabactin resistance-like protein, ABA receptor) and COR413 (cold-regulated 413 plasma membrane 1). In conclusion, these result provide a foundation for understanding the mechanisms of freezing stress tolerance in rapeseeds. Further functional studies should be performed on the freezing stress-related genes identified in this study, which can contribute to the transgenic and molecular breeding for freezing stress tolerance in rapeseed.

• Journal of Korean Society of Environmental Engineers
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• 제22권12호
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• pp.2247-2254
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• 2000

This study was carried out to investigate the reaction characteristics of NOx with reagents to grope the power consumption rate reduction and NOx removal rate improvement for the non-thermal plasma denitrification process. The experiments were performed using the real flue gas and wire-plate type plasma reactor. and the flow rate of real flue gas is $20Nm^3/hr$. Paraffinic and olefinic hydrocarbons and ammonia were used as reagents. Olefinic hydrocarbon oxidizes NO more actively than paraffinic hydrocarbon under the non-thermal plasma conditions, resulting in the generation of large amount of $NO_2$ and a very small amount of CO. When the initial NOx concentration increases. oxidation rate of NO decreases and the consumption rate of olefinic hydrocarbon increases significantly. On the other hand. $NH_3$ did not promote reduction reaction with NO under non-thermal plasma conditions. however, there was a tendency that the NHa was effective to remove the $NO_2$ oxidized by olefinic hydrocarbon.

• Proceedings of the KAIS Fall Conference
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• 한국산학기술학회 2011년도 춘계학술논문집 1부
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• pp.320-322
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• 2011

저온에서의 탈질능력이 우수한 망간계 촉매를 바탕으로 수소-TPR 장치를 사용하여 저온에서의 활성을 파악하였다. 상기 결과를 바탕으로 주요 공정조건인 반응온도, 유속, 수분함량, 주입물 농도, 주입가스 중 수분함량 등에 대한 탈질능의 변화를 조사하였다. 실험결과 망간계 촉매의 경우 반응온도가 증가할수록 탈질능력은 감소하였으며 수분함량에 대해서도 탈질효율이 크게 영향을 받음을 알 수 있었다.