• 산업기술연구
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• 제3권
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• pp.87-94
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• 1983

Heating characteristics of red pepper paste packed in report pouches of various thicknesses and their storage stability were investigated to determine the adequate processing conditions that good bacteriological safty and minimal quality changes could be obtained, when sterilized by using a steam-air system retort. A heat penetration into pouch-packed red pepper paste was carried out through by a conductive heat transfer, indicating a simple logarithmic heating curve, and the smaller thickness revealed the higher heat penetration rate, suggesting the possibility of high temperature-short time sterilization of red pepper paste. The processing conditions with Fo-value of 4.5 or higher were sufficient for keeping up bacterial safty, but based on C-value, better quality retention was obtained at pouch thickness of 15mm under the processing temperature of $120^{\circ}C$. Subsequent storage study revealed that the red pepper paste packed in 15mm and processed at $120^{\circ}C$ with Fo=4.5 could be held without any spoilage and overall acceptance change, when stored for 6 months at room temperature under the relative humidity of 70%. After 3 months storage in $38^{\circ}C$ under saturation humidity, overall acceptance of red pepper paste were judged not to be maintainable on the acceptable level, but it may be suggested that above the results could be kept up a desirable quality without any remarkable deterioration.

• 한국수산과학회지
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• 제23권5호
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• pp.401-406
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• 1990

In order to assess fish meal as food protein source which contains heat denatured pro-tein, functional properties of fish meal protein to be treated with alkaline were examined. Ratio of fish meal to 0.2N NaOH solution for extract solvent which were 1:10 showed good results of extracted and recovered amount of fish meal protein. pH 4.5, solubility of protein treated with alkaline revealed the lowest value. Until concentrations of alkaline treated protein solution reached $0.7\%$, its emulsifying capacity steeply decreased. Emusifying capacity of alkali treated protein were higher value at pH 9.0 than pH 4.0 and 7.0, and also were higher quantity in 0.5M NaCl solution than that of 0.1M. Heating time of fish meal protein to be treated with alkaline reached until 30 mins, its fat binding capacity indicated little change and that of heating time 60 mins decreased. Gel forming concentrations of fish meal protein to be treated with alkali for 15 mins or less were $20\%$ but those of 30 and 60 mins were $25\%$. When treating time of fish meal protein with alkali solution reached till 20 mins, viscosity of alkali treated protein solution steeply decreased.

• Journal of the Korean Wood Science and Technology
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• 제48권5호
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• pp.732-744
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• 2020

본 연구에서는 졸참나무를 반탄화 처리 후 성형숯 형태로 제작하여 물성과 연료특성 및 연소과정에서 발생되는 유해가스 정량분석을 수행하였다. 또한, 대조군으로 시중에서 유통 중인 구이용 성형숯을 선정하여 비교분석하였다. 그 결과, 반탄화 시험편의 고위발열량은 구이용 성형숯 보다 약 14% 높았으며, 회분함량은 약 51배 낮았다. 또한, 밀폐된 챔버에서 각각의 시험편을 900 s간 연소시켰을 때 발생되는 유해가스(일산화탄소, 질산화합물, 이산화황)를 정량평가한 결과, 반탄화 시험편에서 발생한 일산화탄소의 발생량의 최대값이 기존 성형숯보다 약 50배 낮은 것으로 확인되었다. 따라서, 본 연구에서 제작한 반탄화 시험편이 시중 성형숯보다 고위발열량이 높고 연소과정에서 일산화탄소 발생량이 현저히 적은 것으로 나타났다.

• 한국식품조리과학회지
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• 제9권1호
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• pp.43-51
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• 1993

Buckwheat protein isolate was tested for the effects of pH, addition of sodium chloride and heat treatment on solubility, emulsion capacities, emulsion stability, surface hydrophobicity, foam capacities and foam stability. The solubility of buckwheat protein isolate was affected by pH and showed the lowest value at pH 4.5, the isoelectric point of buckwheat protein isolate. The solubility significantly as the pH value reached closer to either ends of the pH, i.e., pH 1.0 and 11.0. The effects of NaCl concentration on solubility were as follows; at pH 2.0, the solubility significantly decreased when NaCl was added; at pH 4.5, it increased above 0.6 M; at pH 7.0 it increased; and at pH 9.0 it decreased. The solubility increased above $80^{\circ}C$, at all pH ranges. The emulsion capacity was the lowest at pH 4.5. It significantly increased as the pH approached higher acidic or alkalic regions. At pH 2.0, when NaCl was added, the emulsion capacity decreased, but it increased at pH 4.5 and showed the maximum value at pH 7.0 and 9.0 with 0.6 M and 0.8 M NaCl concentrations. Upon heating, the emulsion capacity decreased at acidic pH's but was maximised at pH 7.0 and 9.0 on $60^{\circ}C$ heat treatment. The emulsion stability was the lowest at pH 4.5 but increased with heat treatment. At acidic pH, the emulsion stability increased with the increase in NaCl concentration but decreased at pH 7.0 and 9.0. Generally, at other pH ranges, the emulsion stability was decreased with increased heating temperature. The surface hydrophobicity showed the highest value at pH 2.0 and the lowest value at pH 11.0. As NaCl concentrationed, the surface hydrophobicity decreased at acidic pH. The NaCl concentration had no significant effects on surface hydrophobicity at pH 7.0, 9.0 except for the highest value observed at 0.8 M and 0.4 M. At all pH ranges, the surface hydrophobicity was increased, when the temperature increased. The foam capacity decreased, with increased in pH value. At acidic pH, the foam capacity was decreased with the increased in NaCl concentration. The highest value was observed upon adding 0.2 M or 0.4 M NaCl at pH 7.0 and 9.0. Heat treatments of $60^{\circ}C$ and $40^{\circ}C$ showed the highest foam capacity values at pH 2.0 and 4.5, respectively. At pH 7.0 and 9.0, the foam capacity decreased with the increased in temperature. The foam stability was not significantly related to different pH values. The addition of 0.4 M NaCl at pH 2.0, 7.0 and 9.0 showed the highest stability and the addition of 1.0 M at pH 4.5 showed the lowest. The higher the heating temperature, the lower the foam stability at pH 2.0 and 9.0. However, the foam stability increased at pH 4.5 and 7.0 before reaching $80^{\circ}C$.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1999년도 추계 학술대회논문집
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• pp.65-70
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• 1999

Radiative heating of a liquid rocket base plane due to plume emission is numerically investigated. Calculation of flow and temperature fields around rocket nozzle precedes and thereby realistic plume shape and temperature distribution inside the plume are obtained. Based on the calculated temperature field, radiative transfer equation is solved by discrete ordinate method. The averaged radiative heat flux reaching the base plane is about $5kW/m^2$ at the flight altitude of 10.9km. This value is small compared with radiative heat flux caused by constant-temperature (1500K) plume emission, but it is not negligibly small. At higher altitude (29.8km), view factor between the babe plane and the exhaust plume is increased due to the increased expansion angle of the plume. Nevertheless, the radiative heating disappears since the base plane is heated to high temperature (above 1000K) due to convective heat transfer.

• Architectural research
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• 제15권4호
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• pp.201-206
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• 2013

Special attention is required for the design of windows due to their high thermal vulnerability. This paper examines the problems that might arise in the application of the u-value, by reflecting the changes in the u-value of the window, depending on the window-to-wall ratio obtained in an energy demand analysis. Research indicates that the u-value of a window increases with an increase in the difference between the u-values of the frames and the glass. Relative to the changes in the u-value of the windows, the energy demand varied from 1.3% to 9.3%. Windows with a g-value of 0.3 or 0.5 displayed a higher energy demand than windows with a g-value of 0.7. Therefore, when the difference between the performance of the glass and the frame is significant, especially when the g-value is small, a modified heat transmission coefficient should be applied to the window size during the evaluation of the building energy demand.

• 한국식생활문화학회지
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• 제20권4호
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• pp.421-425
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• 2005

전처리 조건을 달리하여 얻은 추출물의 일반성분을 측정한 결과, 수분은 비열처리-효소 추출구보다 열처리-효소 추출구가 다소 높았으며, 조회분과 조펙틴은 유의적인 차이가 없었다. 상등액 추출율은 celluclast와 pectinex의 효소처리 했을때 무열처리-효소 추출구보다 열처리-효소 추출구가 다소 높게 나타났다. 젤리의 adhesiveness 값은 열처리-효소 추출구 일수록 그리고 Celluclast 효소만 처리했을 때 높게 나타났다. Celluclast 효소를 첨가하여 제조한 젤리에서만 값들이 증가하는 경향을 나타냈고 나머지 Pectinex 효소나 혼합효소를 첨가하여 제조한 젤리에서는 값들이 모두 감소하는 결과를 나타냈다. 비열처리-효소 추출구에서는 Celluclast효소와 Pectinex효소를 첨가하여 제조한 젤리는 커다란 차이를 보이지 않았지만 혼합효소를 첨가하여 제조한 젤리에서는 L값이 높은 증가율을 나타냈고 a값은 녹색도를 나타내는 (-)값이 더 증가하였다. 열처리-효소 추출구 젤리가 비열처리-효소 추출구 젤리보다 맛과 조직감 면에서는 약간 우수하였으나 다른 항목들에서는 보편적으로 비열처리-효소 추출구 젤리가 더 나은 결과를 나타냈다.

• Journal of Biosystems Engineering
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• 제37권5호
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• pp.296-301
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• 2012

Purpose: Combustion and fuel qualities of the animal-fats biodiesel as a heating fuel for agricultural hot air heater were studied. Methods: Biodiesel (BD) was made from animal-fats by reacting with methanol and potassium hydroxide in the laboratory. The biodiesel made in the laboratory was tested for fuel and combustion qualities. Results: The kinematic viscosity and the calorific values of the biodiesels were measured. Kerosene based biodiesel, BD20 (K) showed 18 cSt at $-20^{\circ}C$. It seemed that BD100 was not suitable for a heating fuel under some temperature. As BD content increased, the calorific value decreased up to 40,000 J/g for BD100, while the calorific value of light oil was 45,567 J/g showing difference of 5,567 J/g, about 12% difference. Several different fuels including BD20 (biodiesel 20% + light oil 80%), BD50 (biodiesel 50% + light oil 50%), BD100 (biodiesel 100%), and light oil were tested for fuel combustion qualities for agricultural hot air heater, and their combustion performances were compared and analyzed. Flame dimensions of biodiesels and light oils were almost the same shape at the same combustion condition. Generally, the $CO_2$ amounts of BDs were greater than light oil. However, in this study the differences were minor, so there was no significant difference existed between the BDs combustion and light oil. Conclusions: It seemed that quality was good for heating oil for agricultural hot air heater because of showing no barriers for continuous combustion and proper exhaust gas temperature and $CO_2$ amount discharged. But, for fuel fluidity for higher BD content fuel could be a detrimental problem in situations where the outdoor temperature is lowered. As BD content increased, calorific value decreased up to 40,000 J/g for BD100. Calorific value difference between BD20 and light oil was about 1,360 J/g.

• 자원리싸이클링
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• 제23권2호
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• pp.46-52
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• 2014

본 논문은 마이크로파와 고온발열체에 의한 유류오염토양의 정화효율에 관한 연구를 정리한 것이다. 수분의 함량은 처리량에 따라 측정이 되었는데 상대적으로 짧은 시간에 300 g에 도달했다. TPH(Total Petroleum Hydrocarbons)처리 속도는 SiC 발열체를 단독으로 사용했을 때와 비교하였을 때, SiC와 활성탄을 4 kW/kg에서 동시에 사용했을 때 70.1%의 제거율로 가장 높은 값을 보여주었다. 특히, 3 kW/kg때를 제외하고는 전력이 증가할수록 처리속도도 증가하였다. SiC와 활성탄으로 제작된 발열체를 사용할 경우, 내부 온도가 $300^{\circ}C$를 초과하였으며, 4 kW로 2분동안 유지되었을 때 온도가 다시 하락하였으나, 8분이후에는 다시 온도가 상승하였다. 이러한 결과를 기초로 하여, 샘플을 처리하기 위한 에너지량은 마이크로파의 전력에 따라 계산이 되었으며, TPH처리 상수는 유류오염토양의 처리 특성에 관한 다양한 실험에 의해 측정이 되었다.

• 한국식품과학회지
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• 제44권1호
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• pp.28-33
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• 2012

자색 고구마 뻥튀기의 실험결과는 색도 중 $L^*$ 값이 팽화시간이 증가할수록 $L^*$값이 감소하는 유의적인 차이를 나타내었으나 수분함량이나 팽화온도에 따른 차이는 나타내지 않았다. $a^*$값은 팽화시간, 팽화온도가 증가함에 따라 함께 증가하는 유의적 차이를 나타냈으며, $b^*$값은 몇몇 시험구에서 팽화시간과 팽화온도가 증가할수록 $b^*$값도 증가하였다. 비체적은 수분함량과 팽화온도가 높아질수록 증가하였고, 수분함량 11%, 팽화온도 $246^{\circ}C$, 팽화시간 4초에서 제조한 시험구가 가장 높은 값을 나타내었다. 또한 자색 고구마 뻥튀기의 파괴력은 팽화온도와 팽화시간이 증가함에 따라 함께 증가하며 수분함량이 낮을수록 높은 파괴력을 나타내는 유의적인 차이를 보였다. 관능평가에서 7% 수분함량, 팽화온도 $246^{\circ}C$, 팽화시간 5초에서 제조한 뻥튀기가 패널들에게 높은 점수를 얻었다.