• Journal of Hydrogen and New Energy
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• 제29권1호
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• pp.25-31
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• 2018

To apply Sievert's type apparatus to thermal analysis of hydrogen absorption materials, the dehydrogenation of $LaNi_5$ system was investigated. As the initial wt% of hydrogen was increased from 0.44 to 1.24 wt%, the peak temperature of evolution rate shifted to higher temperature. However, with the initial wt% of hydrogen higher than 0.95 wt%, the peak temperature of evolution rate did not change. As the heating rate was increased, the peak temperature increased; the peak temperatures for heating rates 0.5, 1.0 and 1.5 K/min were 262.2, 264.1, and 265.9 K respectively. The Sievert's type automatic apparatus can be successively applied to the thermal analysis of $LaNi_5$ hydride.

• Journal of the Korean Home Economics Association
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• 제35권2호
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• pp.147-157
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• 1997

It attempted to determine the effect of various thawing methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature, on the quality of frozen cooked rice using Nongan variety of rice. These effects were analysed at three different periods-after 10 days, 30 days and 90 days. It conducted a physico-chemical analysis(moisture content, dehydration rates, color value and texture) and sensory evaluation o the frozen-thawed cooked rice. The study showed that there were no significant differences on the frozen-thawed cooked rice. The study showed that there were no significant differences on the quality characteristics of frozen-thawed cooked rice during the storage of 90 days. However, the thawing method of pressure cooking caused high moisture content and decrease in hardness on the cooked rice, the desirability for the rice didn't diminish compared with the cooked rice just after cooking. the quality characteristics of the cooked rice after frozen-thawing by conventional cooking and microwave heating were similar with that of the cooked rice just after cooking. thawing at room temperature caused a significant decrease in quality characteristics.

• Journal of Advanced Marine Engineering and Technology
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• 제23권1호
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• pp.54-61
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• 1999

The fully developed turbulent momentum and heat transfer induced by the roughness elements on the outer wall surfaces in concentric annuli are analytically studied on the basis of a modified turbu-lence model. The resulting momentum and heat transfer are discussed in terms of various parame-ters such as the radius ratio the roughness density Reynolds number and Prandtl number accord-ing to the heating condition. The study shows that certain artificial roughness elements may be used to enhance heat transfer rates with advantage from the overall efficiency point of view.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.665-667
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• 2005

VIATRON TECHNOLOGIES has developed FE-RTP system that enables LTPS LCD and AMOLED manufacturers to produce poly-Si films at low cost, high throughput, and high yield. The system employs sequential heat treatment methods using temperature control and rapid thermal processor modules. The temperature control modules provide exceptionally uniform heating and cooling of the glass substrates to within ${\pm}2^a\;C$. The rapid thermal process that combines heating with field induction accelerates the treatment rates. The new FE-RTP system can process $730{\times}920mm$ glass substrates as thin as 0.4 mm. The uniform nature of poly-Si films produced by FE-RTP resulted in AMOLED panels with no laser-Muras. Furthermore, FE-RTP system also showed superior performances in other heat treatment processes involved in poly-Si TFT fabrications, such as dopant activation, gate oxide densification, hydrogenation, and pre-compaction.

• Journal of the Korean Institute of Telematics and Electronics
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• 제27권9호
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• pp.1386-1392
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• 1990

Characteristics of the direct thermal nitrided films by RF induction heating has been studied. The nitrided films on Si were prepared at 1000-1200\ulcorner in ammonia gas ambient. The nitrided films were analyzed by ellipsometry an Auger electron spectroscopy. I-V and C-V characteristics of MIS capacitors fabricated using nitrided film were investicated. The nitrided films were grown up mostly within initial thirty minutes and no significant growth was observed thereafter. Etch rates of films were about 1\ulcornermin in diluted HF (HF:H2O= 1:50). The nitrided films were resistant to dry and wet oxidations at temperatures below 1000\ulcorner and 900\ulcorner, respectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• 제19권12호
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• pp.883-888
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• 2007

As a starting point of investigating what molecular dynamic simulations can reveal about the nature of atomic level of heating and cooling process, argon described by the LJ potential is considered. Stepwise heating and cooling of constant rates are simulated in the NPT (constant number, pressure and temperature) ensemble. Hysteresis is found due to the superheating and supercooling. Drastic change of volume and energy is involved with phase change, but the melting point can not be obtained by simply observing the changes of these quantities. Since liquid and solid phases can co-exist at the same temperature, Gibbs free energy should be calculated to find the temperature where the Gibbs free energy of liquid is equal to that of the solid since the equilibrium state is the state of minimum Gibbs free energy. The obtained melting temperature, $T^*=0.685$, is close to that of the experiment with only 2% error.

• Corrosion Science and Technology
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• 제5권1호
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• pp.1-4
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• 2006

Martensitic stainless steel is used when mechanical properties such as high tensile strength and hardness are required. Medium carbon-contained martensitic stainless steel which contains more than 0.2 wt% of carbon should be heat-treated and quenched at the temperature where undissolved carbides are totally dissolved into the matrix. In particular, the dissolution and reprecipitation behaviors of various forms of carbides are affected by such parameters as heating rate, heating temperature, duration time and cooling rate. This study is to investigate the effects of heat treatment parameters of 14Cr-3Mo martensitic stainless on corrosion resistance and phase transformation in relation to the dissolution and reprecipitation of carbides.

• Elastomers and Composites
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• 제23권3호
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• pp.213-222
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• 1988

The thermal decomposition of poly(n-butyl methacrylate)(Pn-BMA) was studied using a dynamic and isothermal thermogravimetry in nitrogen gas with 50ml/min at several heating rates from 1 to $20^{\circ}C/min$, and at several heating temperature from 320 to $370^{\circ}C$. The mathematical techniques used for calculation of activation energy were Kissinger, Anderson, Chatterjee-Conrad, Friedman, Fuoss, Ozawa and isolthermal method. The range of activation energies obtained using the several techniques was between 43 and 51Kcal/mol except Chatterjee-Conrad and this range agreed with each other very well. The thermal degradation of Pn-BMA was considered to be carried out by main chain scission.

• Journal of Environmental Health Sciences
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• 제18권1호
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• pp.58-62
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• 1992

The objective of this study is to investigate the generation rates, composition, propertion and lower heating values of each material in the municipal solid wastes(MSW) as well as the effect of landfill leachate on the environment in Taejon. The results are as follows: 1. The annual average generation rate of MSW in Taejon is approximately 1.7kg/c.d. 2. The weight percent of combustible matters is on average 80 and the lower heating value of MSW is measured to be more than 1,700 kcal/kg after removing the briquette component. 3. It is necessary for us to take a proper management system for leachate treatment in the landfill because it has many problems in the sewage and groundwater. 4. It is recommeded that MSW be treated by multiple methods such as the sanitary landfill, resources and recovery, composting and incineration.

• Journal of the Korea Institute of Military Science and Technology
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• 제6권3호
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• pp.103-110
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• 2003

The present work was conducted to achieve the better understanding of the performance analysis technique for the expander type air turbo ramjet engine. For this purpose, the performance analysis was carried out using a small engine(8.0kN thrust) with two types of fuels. From this analysis, at the same input condition, the thrust of methane-fueled engine was 25% lower than that of hydrogen. In addition, the case of methane shows the inapplicable engine performance cycle.(i.e., The compressor work exceeds the turbine output power) These results come mainly from the different heating value of each fuel and specific heat. This analysis also shows that, to build a same performance cycle as the hydrogen case, the methane-fueled engine requires increased air and fuel flow rates, increased turbine expansion ratio, and decreased compressor pressure ratio.