• 한국미생물·생명공학회지
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• 제19권1호
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• pp.100-108
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• 1991

Molecular characteristics and improving methods for thermal stability of enzyme have been considered. Intrinsic and extrinsic stabilizing mechanisms are two governing principles for enhanced thermal stability of enzyme in molecular basis. Factors contributing to the former and the latter mechanisms may be involved in the enhanced thermal stability of enzyme complementarily. Also, the methods for improving thermal stability of enzyme which comprise reaction in organic solvent system, chemical modification, immobilization, sequential unfolding and refolding, gene manipulation techniques and enzyme-antibody complexing are reviewed.

• 유기물자원화
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• 제22권1호
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• pp.27-34
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• 2014

하수슬러지의 처리 및 재활용에 관한 다양한 연구가 진행되었지만 하수슬러지 내에 포함된 80% 이상의 함수율에 따른 높은 에너지 소비 비용으로 저비용의 처리 기술의 요구가 높다. 이에 본 연구에서는 슬러지 처리 시 적은 양에 에너지를 소비하는 열가용화 반응을 적용하여 열가용화 반응온도에 따른 하수슬러지의 점도를 정량화하고자, 반응온도에 따른 탈수슬러지의 토크를 연속적으로 측정하였다. 반응온도가 증가하면 높은 반응온도와 압력에 의해 탈수슬러지는 열가용화 진행되고 슬러지 세포내의 결합수가 자유수로 용출되어 고상의 탈수슬러지는 액상의 슬러리로 변환된다. 이에 반응온도에 따른 점도 측정 결과 293K에서는 $270,180kg/m{\cdot}sec$ 로 높은 점도 값을 보이지만 400K에서는 $12kg/m{\cdot}sec$ 급격히 감소하고 460K 이상에는 $4kg/m{\cdot}sec$로 물의 점도와 유사한 값을 나타낸다. 이 결과를 바탕으로 수치모델링으로 열가용화 반응기 최적 설계를 위한 경계조건으로 점도 함수를 확보하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.684-687
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• 2007

Research on the solar thermal hybrid power generation technology which uses solar thermal chemical reaction has been carried out in KIER, The research covers development of solar concentration system and solar reactor for methane steam reforming reaction. This paper introduces a brief review and prospects of oversea's researches in similar areas and KIER's research progresses up to now.

• 한국수소및신에너지학회논문집
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• 제24권4호
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• pp.275-281
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• 2013

This study was conducted to increase the amount of bio-hydrogen production from microalgae(Chlorella vulgaris) in batch reactors by thermal pre-treatment. The optimization of thermal pre-treatment was conducted using statistic experimental design of response surface methodology. Two experimental parameters of temperature and reaction time were considered. The optimization condition was founded at the coded variables of <0.52, -0.07> corresponding to the experimental of heating temperature of $95.6^{\circ}C$ and reaction time of 57.9 min, respectively. Under the optimal condition, the maximum hydrogen production was predicted to 25.3mL $H_2/g$ dry cell weight (dcw), which was 9.1 times higher value of control(2.8mL $H_2/g$ dcw).

• Preventive Nutrition and Food Science
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• 제21권2호
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• pp.160-164
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• 2016

Two onions (Sulfur-1 and Sulfur-4) cultivated with different sulfur applications were thermally processed to elucidate the effects of heat treatment on browning index and antioxidant activity. Sulfur-4 onion had higher sulfur content compared with the Sulfur-1 onion. After thermal processing, browning intensity was different between the two onions juices, with lower values observed for Sulfur-4 onion juice. This suggests that sulfur inhibits the Maillard browning reaction. The total reducing capacity of the juices increased at higher thermal processing temperatures; however, it was also lower in the Sulfur-4 onion juice. This suggests that the heat treatment of onions enhanced their antioxidant activity, but the effect was offset in the Sulfur-4 onion juice presumably due to higher sulfur content. This study indicates that sulfur, a core element for the functionality of onions, can decrease the antioxidant activity of thermally processed onions because of its potential as a Maillard reaction inhibitor.

• 한국기계가공학회지
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• 제17권5호
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• pp.137-142
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• 2018

With the development of the electronic-materials industry, multi-functional metal-composite materials with high thermal conductivity and low thermal expansion must be developed for high reliability and high life expectancy. This paper is a preliminary study on the manufacturing technology of gas reaction control composite material, focusing on the prediction of the equivalent thermal properties of Al-AlN composite materials. Numerical equivalent property values are obtained by using finite element analysis and compared with theoretical formulas. Al-AlN composite materials should become the optimal composite material when the proportion of the reinforcing phase is less than 0.5.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2018년도 공동국제학술발표회
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• pp.82-82
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• 2018

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1193-1197
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• 2006

The novel oligomers were synthesized by Grignard reaction, the suzuki coupling reaction, etc. The oligomers were characterized by Infrared (IR), Mass spectrometer (MS). Their thermal properties were investigated by differential scanning calorimetry (DSC) and Thermogravimetric analysis (TGA). The new oligomers showed high thermal stability above $300^{\circ}C$.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1998년도 제17회 KOSCI SYMPOSIUM 논문집
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• pp.155-164
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• 1998

Numerical analysis was performed with multicomponent transport properties and detailed reaction mechanisms for axisymetric 2-D CH4 jet diffusion, partial premixed, premixed flame. Calculations were carried out twice with C2-Full Mechanism including prompt NO reaction in addition to the above C2-Thermal NO Mechanism. The role of thermal NO mechanism and prompt NO mechanism on each flame's NO production is investigated by using the numerical result. The NOx production of each flame were evaluated Quantitatively in terms of the NOx emission index

• Bulletin of the Korean Chemical Society
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• 제16권1호
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• pp.47-52
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• 1995

The mechanism of the photodecomposition of 2-methoxy-1,2-diphenyl diazoethane has been investigated in methanol and isoprene using time-resolved laser flash photolysis techniques. The reaction of triplet carbene which is generated from 2-methoxy-1,2-diphenyl diazoethane with methanol is believed to proceed via thermal excitation to the singlet state. The activation energy and enthalpy are consistent with a mechanism involving thermal equilibrium between the triplet and singlet state followed by the reaction of the singlet with methanol to give ether.