• 한국식품조리과학회지
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• 제9권1호
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• pp.33-36
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• 1993

본 실험에서는 생강에서 추출한 crude gingerol의 열 안정성 및 대두유의 산화에 미치는 crude gingerol의 농도에 따른 항산화 효과를 검토하였다. $105^{\circ}C$에서 3시간 가열된 crude gingerol에는 94.5%의 gingerol이 잔존하는 반면, $165^{\circ}C$에서 30분간 가열된 경우에는 10.2%의 gingerol이 잔존하였다. 0.02%, 0.1% 및 0.2%의 crude gingerol이 첨가된 대두유를 $105^{\circ}C$에서 5시간 또는 $165^{\circ}C$에서 30분간 열처리한 후 $45^{\circ}C$에서 저장하면서 과산화물가의 변화를 측정하여 crude gingerol의 항산화효과를 BHT와 비교하였다. 0.02%, 0.1% 및 0.2%의 crude gillgerol이 첨가된 대두유를 $105^{\circ}C$에서 5시간 열처리 후 crude gingerol 첨가군은 BHT 첨가군보다 항산화 효과가 높았으며, 이 대두유를 $45^{\circ}C$에 저장하는 경우 crude gingerol의 항산화 효과는 gingerol의 농도가 증가함에 따라서 증가하였다. $165^{\circ}C$에서 30분간 열처리 한 후 $45^{\circ}C$에 저장된 0.02%, 0.1% 및 0.2%의 crude gingerol이 첨가된 대두유에서 crude gingerol의 농도가 증가함에 따라 그 항산화 효과가 증가하였다.

• 보존과학회지
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• 제31권1호
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• pp.13-20
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• 2015

목조문화재는 수분의 영향으로 열화의 가속화가 진행되기 때문에 전통적으로 표면을 수분으로부터 차단하기 위해 들기름 및 동유와 같은 유지류를 도포하였다. 그러나 목조문화재에 적합한 유지류 코팅 방법 및 성능에 대한 체계적인 연구가 부족한 실정이다. 본 연구는 천연 유지류 3종과 오일스테인 2종의 목재의 방향별, 공시재의 시간 경과 및 유지류의 중탕 여부에 따른 방수 성능을 평가하여 현장 적용 가능성을 판단하였다. 건전 목재의 섬유방향에서 상온의 천연유지류 코팅제 방수성능은 대조군과 비교하여 약 79.2%를 차단하였으며, 특히 동유는 90.5%의 수분을 차단할 정도로 우수한 성능을 나타냈다. 2년간 실내에서 컨디셔닝을 실시한 경우 유지류의 방수 성능은 약 8.8% 감소하였다. 유지류를 중탕하여 사용할 경우 약 5.0%의 방수 성능이 향상되며, 특히 아마인유는 중탕하여 사용할 경우 약 9.6%의 방수 성능을 개선할 수 있다.

• 한국식품조리과학회지
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• 제32권4호
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• pp.383-389
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• 2016

Purpose: This study was conducted to evaluate the effect of rehydration and subsequent heating at high temperature on the pigments and antioxidants of dried samnamul (Aruncus dioicus) and daraesoon (Actinidia arguta). Methods: Rehydration included 16 h-soaking in cold water, and 30 min-boiling and 1 h-infusion in water. Rehydrated samnamul and daraesoon were heated at $180^{\circ}C$ for 10 or 20 min with or without perilla oil addition (10%) for cooking. Pigments and antioxidants were determined by HPLC and spectrophotometry. Results: Rehydration caused decreases in pigment and polyphenol contents, but increase in tocopherol content. Cooking by heating without addition of perilla oil resulted in increases in chlorophyll and carotenoid contents, but decreases in polyphenol and tocopherol contents. Decrease in tocopherol content by heating at $180^{\circ}C$ was reversed by the addition of perilla oil. Conclusion: This study strongly suggested that cooking of samnamul and daraesoon at $180^{\circ}C$ with perilla oil could improve color, texture, and potential health functionality by recovering the loss of antioxidants and pigments with antioxidant activity.

• 한국식품영양과학회지
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• 제23권4호
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• pp.654-659
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• 1994

대두유와 면실유를 $160^{\circ}C,\;180^{\circ}C,\;200^{\circ}C\;및\;220^{\circ}C$에서 60시간 연속 가열하면서 이 때 일어나는 물리화학적 특성변화를 살펴보고 이들 간의 상관관계를 조사하였다. 가열시간이 경과함에 따라 산가, 카르보닐가, 요오드가, 점도, 중합체 함량은 증가하였고, 요오드가는 감소하였으며, 가열온도 $180^{\circ}C$ 이하에서는 이들의 변화가 낮았고, $200^{\circ}C$ 이상에서는 전체적으로 높게 나타났다. 점도와 산가 변화의 상관도는 대두유 0.9843, 면실유 0.9819이었고, 점도와 카르보닐가의 변화에서는 대두유 0.9779, 면실유 0.9797이었다. 점도와 요오드가의 변화에서는 대두유 0.9852, 면실유 0.9948로 나타났다. 이상의 결과는 튀김유의 가열산화에 있어서 점도의 변화를 측정함으로써 산가, 카르보닐가 및 요오드가의 변화를 비교적 정확하고 빠르게 예측할 수 있음을 시사하고 있다고 사료된다.

• Journal of Ginseng Research
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• 제42권3호
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• pp.320-326
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• 2018

Background: Explosive puffing can induce changes in the chemical, nutritional, and sensory quality of red ginseng. The antioxidant properties of ethanolic extracts of red ginseng and puffed red ginseng were determined in bulk oil and oil-in-water (O/W) emulsions. Methods: Bulk oils were heated at $60^{\circ}C$ and $100^{\circ}C$ and O/W emulsions were treated under riboflavin photosensitization. In vitro antioxidant assays, including 2,2-diphenyl-1-picrylhudrazyl, 2,2'-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid, ferric reducing antioxidant power, total phenolic content, and total flavonoid content, were also performed. Results: The total ginsenoside contents of ethanolic extract from red ginseng and puffed red ginseng were 42.33 mg/g and 49.22 mg/g, respectively. All results from above in vitro antioxidant assays revealed that extracts of puffed red ginseng had significantly higher antioxidant capacities than those of red ginseng (p < 0.05). Generally, extracts of puffed red and red ginseng had high antioxidant properties in riboflavin photosensitized O/W emulsions. However, in bulk oil systems, extracts of puffed red and red ginseng inhibited or accelerated rates of lipid oxidation, depending on treatment temperature and the type of assay used. Conclusion: Although ethanolic extracts of puffed red ginseng showed stronger antioxidant capacities than those of red ginseng when in vitro assays were used, more pro-oxidant properties were observed in bulk oils and O/W emulsions.

• 한국기계가공학회지
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• 제18권2호
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• pp.82-90
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• 2019

In this paper, the effects of different 3D printing conditions including oil lubrication and annealing are observed for their effects on tensile testing. In 3D printing, a press-out extrude filament is rapidly heated and cooled to create internal stress in the printed part. The 3D printing internal stress can be removed using oil-coated filament and annealing. During the oven cooling at an annealing temperature of $106^{\circ}C$, the stress of the specimens with laminated angle $0^{\circ}$ tends to increase by 12.6%, and that of the oil-coated filament printing specimens is increased by 17%. At the annealing temperature of $106^{\circ}C$, the stress of the oil-coated filament printing specimens tends to increase by 35%. In this study, we have found that the oil lubrication and annealing remove the internal stresses and increase the strength of the printed specimens. The oil lubrication and annealing reform the crystalline structures to even out the areas of high and low stress, which creates fewer fragile areas. These results are very useful for the manufacture of 3D printing products with a suitable mechanical strength for applications.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.624-629
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• 2001

An experimental study was performed to investigate adiabatic wall temperature and heat transfer coefficient around on a module with longitudinal fin heat sink cooled by forced air flow. In the first method, inlet air flow(1-7m/s) and input power(3-5W) was varied after a heated module were placed on an adiabatic floor($320{\times}550{\times}1mm^{3}$). An adiabatic wall temperature was determinated to use liquid crystal film(LCF). In the second method to determinate heat transfer coefficient, inlet air flow(1-7m/s) and the heat flux of rubber heater($0.031-0.062\;W/cm^{2}$) was varied after an adiabatic module was placed on rubber heater covering up an adiabatic floor. In addition, surface oil-film visualization were performed to characterize the macroscopic flow-field around a module.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.88-94
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• 1999

This study is to investigate the effects of warm deep drawing with steel sheets of SCP3C and SCP1 for improving deep drawability. Experiments were carried out in various working conditions such as forming temperature and lubricantion. The effect of lubricantion and temperature on drawabillity of steel sheets as well as thickness distribution of drawn oil pan were examined and discussed. One step forming at room temperature and uniform distribution of thickness was achieved at optimum formability for lubricantion. The optimum forming temperature was obtained that both the die and the blankholder were heated to 10$0^{\circ}C$ while the punch was cooled by circulating coolant of $0^{\circ}C$.

• Carbon letters
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• 제2권2호
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• pp.91-98
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• 2001

Porous carbons have been prepared from different parts of banana stems using two different routes, viz., by pyrolysing the mass at different temperatures as well as by treating the dried mass with chemicals followed by pyrolysis. The pyrolysis behaviour of all these materials has been studied up to $1000^{\circ}C$. Samples treated with acids exhibit more increase in surface area as compared to those treated with alkalies or salts. Analysis of BET surface area shows that the carbon prepared at low temperature shows mixed porosity, i.e., micro and mesopores. Samples heated to high temperature above $700^{\circ}C$ show decrease in macroporosity and increase in microporosity. Liquid adsorption studies have been made using methylene blue and heavy oil. The activated carbons so prepared exhibit higher oil adsorption mainly in the macro and mesopores.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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• pp.235-237
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• 2012

Geodae-Uksae 1 is a variety of Miscanthus sacchariflorus recently discovered in Korea. It is being mass-cultivated for use as energy crop due to its superior productivity, as high as 30 ton/ha/yr for the dry mass. This study investigates the method of producing biochar and bio-oil from the crop using slow pyrolysis. Especially, the study focused on assessing the biochar properties for its application to soil to improve soil quality and sequestrate carbon. Using an electrically heated packed bed reactor, the products of slow pyrolysis from Geodae-Uksae 1 were produced over a temperature range of $300-700^{\circ}C$ with a heating rate of $10^{\circ}C/min$. The biochar, condensable vapor (bio-oil) and residual gases were characterized for the physical and chemical properties. It was concluded that the ideal temperature for pyrolysis to produce biochar is $500^{\circ}C$.