• Food Science and Preservation
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• v.8 no.3
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• pp.331-337
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• 2001

The oxidative stability of tallow heated was studied by different frying condition (temperature 130, 150, and 180$^{\circ}C$;heating time, each 10hours per day, total 240hrs). Changes of physicochemical parameters such as acid value, peroxide value, iodine value, dielectric constant, content of polar components and polymer, refractive index, smoke point, viscosity and color changes in tallow heated were also measured. Acid value, dielectric constant, refractive index, viscosity, and content of polar component and polymer increased as the tallow was heated longer, whereas iodine value and smoke point decreased and peroxide value was increased and decreased repeatedly. These parameters changed to a greater extent as the heating temperature went up. The color became darkened with the increase of red and yellow values during heating. The decree of coloration was proportional to heating temperature.

• Korean journal of food and cookery science
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• v.4 no.1
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• pp.9-16
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• 1988

These experiments were carried out to study the factors affecting quality and textural characteristics in the preparation of artificial gluten meat (AGM). These results were compared with the raw beef on its properties. The results obtained were summarized as follows: 1, The affective factors on the color of AGM were walnut, oil, salt, onion, water, interactions of oil and water, and interactions of heating temperature and heating time. 2. Shear force was affected by the factors of walnut, onion, water and interactions of walnut and oil. 3. Walnut, oil, onion, salt, water, interactions of walnut and oil, interactions of oil and water, and heating temperature affected on hardness, springiness, cohesiveness and chewiness. 4. Walnut and water affected on the water holding capacity.

• Journal of environmental and Sanitary engineering
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• v.11 no.1
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• pp.57-61
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• 1996

This study was to decompose carbon tetrachloride and CFC with pyrolytic incineration unit because of prohibition of their usage sooner or later. We have investigated heating value and temperature versus decomposing rate, removal of $Cl_2$ and dust in the flue gas, The results obtained were as follows; 1. In combustion condition to decompose $CCl_4$ heating value was 3,300Kcal/Kg, retention time was 2,0 sec. incinerator exit temperature was $950^{\circ}C$. 2.The removal of HCI and $Cl_2$ in flue gas used NaOH as reagent, then molar ratio o of $Na^+/Cl^-$ was 1.07. 3. NaCI of dust component was more than 90 %, 2 stage venturi scrubber was used to remove dust, then removal rate of dust was 99% over at L/G of $1.7Vm^3$

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.716-717
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• 2006

Gas release behavior from aluminum and Al 7075 alloy powders during heating in argon was investigated by in-situ gas chromatography. Water vapor, hydrogen, carbon mono-oxide were detected as individual evolution spectra against heating temperature and time. The mechanisms of water and hydrogen evolutions were studied in detail for the determination of effective degassing condition. Magnesium in the alloy powder was found to lower the hydrogen evolution temperature to enhance overall hydrogen release.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.12
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• pp.828-836
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• 2010

The drying is a process that involves coupled and simultaneous heat and mass transfer. When a wet solid is subjected to thermal drying, two processes occur simultaneously. Drying is classified according to heat transfer characteristics in terms of conduction, convection and radiation. In thermal drying, radiation is easier to control than conduction and convection drying and involves a relatively simple structure. In this study, we measured energy consumption, surface hardness of paint and surface gloss with variation of surface temperature of drying materials and drying time. Drying characteristics and energy consumption between heating panels and hot air heating have been presented. The present study shows that a dryer using heating panels is more effective than a hot air dryer from the viewpoint of energy conservation. The hot air dryer, however, was not optimized and more studies on various parameters related to drying will need to be investigated for definite comparison of drying characteristics of the dryers. The result, even if limited, would present the effective availability of paint drying.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.828-831
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• 2007

We evaluated the effects of heat treatment on various properties of onion extracts (Allium cepa). Onion was heated at various temperatures ($110-150^{\circ}C$) for various times (1-5 hr), and the total polyphenol, flavonoid, and free sugar contents, and antioxidant activity were investigated. With increased heating temperatures and exposure times, the total contents of polyphenols and flavonoids, as well as antioxidant activity increased. The highest total polyphenol content (189.80 mg/100g) occurred after heating for 2 hr at $140^{\circ}C$. The highest total flavonoid content (252.51 mg/100g) occurred after heating for 3 hr at $150^{\circ}C$. The antioxidant activity assessed using the DPPH method was highest, at 2.1 mg/mL ($IC_{50}$ value), after heating for 2 hr at $150^{\circ}C$. Correlations between antioxidant activity and the total polyphenol, total flavonoid, and fructose contents were highly significant (all p<0.01). The optimal heating time and temperature were 2 hr and $130^{\circ}C$.

• Journal of the Korean Society for Heat Treatment
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• v.33 no.5
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• pp.232-238
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• 2020

Heating experiments using the 7075 aluminum alloy in the state of billet and extrudate have been performed to investigate the pertinent ranges of working temperatures and holding times for the application to the various automobile parts. The 7075 specimens from raw billet of 152 mm in diameter and 400 mm in length prior to extrusion were used for heating with a holding time of 10 minutes at temperatures between 380℃ and 550℃. Then, an extrusion process using the billet has been fulfilled at 380℃ with extrusion speed of 0.8 mm/min to get an plate-type extrudate of 75 mm in width and 4.2 mm in thickness. The samples from the extrudate were subjected to heating experiments at temperatures between 380℃ and 440℃ with holding times such as 10 min, 30 min, 60 min and 120 min at each heating temperature. The microstructures were investigated on the optical and EBSD micrographs. The hardness measurement and the tensile test have been performed to investigate the effect of the heat treatment on the mechanical property. The results showed for the 7075 extrusion process that the safe heating of billet can be performed below 450℃ and the extrusion can be done safely up to 400℃.

• Laser Solutions
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• v.12 no.2
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• pp.17-25
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• 2009

Two methodologies for predicting thermal relaxation time of tissue subjected to pulsed laser irradiation is introduced by the calculation the optical penetration depth and by the investigation of the temperature diffusion behavior. First approach is that both x-axial and y-axial thermal relaxation times are predicted and they are superposed to achieve the thermal relaxation time (${\tau}_1$) for two-dimensional square tissue model. Another approach to achieve thermal relaxation time (${\tau}_2$) is measuring the time required for local temperature drop until $e^{-1}$ of the maximum laser induced heating.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.04a
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• pp.9-12
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• 2007

Recently, research and development related to high strength concrete for the high rise and large scale reinforced concrete building has been actively promoted in worldwide by national and private research project. But, it is reported that violent explosive explosion would be happened when it was exposed in fire. In the existed study, a explosion in a reinforced concrete structure looses the organism by the different contraction and expansion of hardened cement paste and aggregate, and causes crack by thermal stress. In case of the Europe, Japan and America, they have studied the explosion for a long time. However it would hardly study the explosion in domestic, So it is needed base on mechanical properties of fire deterioration in high strength concrete. Therefore, this study is intend as an mechanical properties of specimen to high heating by heating and load test machine and $700^{\circ}C$. As a result, it is willing to propose fundamental data for quick and accurate diagnosis of deteriorated concrete structure by fire damage with experiment according to the design high strength concrete.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.6
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• pp.845-852
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• 2001

The characteristics of evaporation cooling of single droplet on a heated surface were studied experimentally. The two kinds of heater modules were tested to measure cooling characteristics of metal surface (high conductivity) and Teflon surface (low-energy surface, low conductivity). The results showed that time averaged heat flux during droplet evaporation increased exponentially with initial surface temperatures of brass, copper and steel. The heat flux and evaporation time did not varied with metal conductivities. However, the temperature drop after the deposition of droplet was larger on Teflon than on the metals. Thus, the correlation of interface temperature between liquid droplet and metal surface was proposed as a function of the initial surface temperature of heating materials, which could be applied to both metal and non-metal ones.