• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.133-137
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• 2004

In this paper, we investigated impurities content, absorption properties, and thermal properties showing by changing the content of carbon black which is semiconductive materials for underground power transmission. Specimens were made of sheet form with the three of existing resins and the nine of specimens for measurement. Impurities content of specimens and absorption properties were measured by ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometer) and Karl Fisher. And high temperature, heat degradation initiation temperature, and heat weight loss were measured by TGA (Thermogravimetric Analysis). The dimension of measurement temperature was 0$[^{\circ}]$ to 800$[^{\circ}]$, and rising temperature was 10$[^{\circ}/min]$. Impurities content was highly measured according to increasing the content of carbon black from this experimental result also absorption amount was increased according to these properties. Specially, impurities content values of the A1 and A2 of existing resins were measured more than 4000[ppm]. Heat degradation initiation temperature from the TGA results was decreased according to increasing the content of carbon black. All over, heat stabilities were EEA>EBA>pEVA. That is, heat stabilities of EVA containing the weak VA(vinyl acetate) against heat was measured the lowest.

• 한국가스학회:학술대회논문집
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• 1997.09a
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• pp.229-235
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• 1997

A low power (300 mW) catalytic bead combustible gas sensor is developed and utilized with a computer controlled sampling system for measuring heat content of natural gas. The heat content of gas is proportional to the change in the energy required to exposure to the sample of combustible gas. The heat content of natural gas samples ranging 36.30 - 39.88 MJ/$m^3$ is measured in the range of approximately $1\%$ error, which is comparable to its nominal heat content. Each gas has a slightly different curve of sensitivity vs. sensor temperature. Thus there Is no temperature at which all sensitivities are equal. In calibration process the choice of a optimum operating temperature is an important factor that influences the overall performance of the measurement system.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.443-451
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• 2021

This study compared and analyzed the thermal characteristics based on the ratio of moisture content of infected and non-infected Bursaphelenchus Xylophilus by heat of combustion experiment. The experiment results are as follows. The analysisresult of the ratio of water content shows that 19.92% on average for infected Bursaphelenchus Xylophilus and 26.27% for non-infected which decreases water content as the size of conduction, convection, and radiant heat increases in case of fire. As the vaporization of the moisture content accelerates, the average moisture content is reached, and the result is contrary to the thermal characteristics of the wood that the moisture content is not ignited by a heat source when the moisture content is under 15%. The combustion heat analysis result showed that infected and non-infected Bursaphelenchus Xylophilus had no significant difference in combustion heat at about 3%. However, it shows that combustion heat is higher than other species. In conclusion, decreasing in moisture content based on the increasing conduction, convection, and radiant heat is one of the direct causes of ignition, and the lower the moisture content, the faster the fire spreads.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.12
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• pp.570-575
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• 2006

In this paper, we have investigated thermal properties by changing the content of carbon nanotube, which is component part of semiconductive shield in underground power transmission cable. Heat capacity (${\Delta}H$), glass transition temperature (Tg) and melting temperature (Tm) were measured with the samples of eight, through DSC (Differential Scanning Calorimetry), and the measurement ranges of temperature selected from $-100[^{\circ}C]\;to\;100[^{\circ}C]$ with heating temperature selected per $4[^{\circ}C/min]$ Also, high temperature, heat degradation initiation temperature, and heat weight loss were measured by TGA (Thermogravimetric Analysis) in the temperature from $0[^{\circ}C]\;to\;700[^{\circ}C]$ with rising temperature of $10[^{\circ}C/min]$. As a result, the Glass transition temperatures of the sample were showed near $-20[^{\circ}C]{\sim}25[^{\circ}C]$, and the heat capacity and melting temperature from the DSC was increased according to increasing the content of carbon nanotube, while, thermal diffusivity was increased according to increasing the content of carbon nanotube. Also, heat degradation initiation temperature from the TGA results was increasing according to increasing the content of carbon nanotube with CNT/EEA. Therefore, heat stabilities of EVA, which contained the we VA (vinyl acetate), showed the lowest.

• Corrosion Science and Technology
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• v.18 no.1
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• pp.24-32
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• 2019

The effects of zinc coating and heat treatment on the corrosion resistance of aluminum alloys including A1100 and the modified A3003, used as heat exchanger tube were investigated in this study. The grain size of the heat-treated specimen is larger than that of the specimen without heat treatment, but the grain size did not significantly affect the corrosion behavior. The concentration of zinc was noted at 11.3 ~ 31.4 at.% for the as-received Zn-coated samples and reduced to 1.2 ~ 2.4 at.% after the heat treatment, as measured by the scanning electron microscopy (SEM) with an energy dispersive spectrometer (EDS) on the surface. The concentration of oxygen is 22 ~ 46 at.% for the zinc coated specimens while noted at 7.4 ~ 12.8 at.% for the specimens after the removal of the coating. The corrosion behavior depended largely on the concentrations of zinc, aluminum, and oxygen on the specimen surface, but not on the Mo content. The corrosion potential was high and the corrosion rate was low for a specimen with a low zinc content, a high aluminum content, and a high oxygen content.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.489-494
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• 2004

In this paper, we investigated impurities content and thermal properties showing by changing the content of carbon black which is semiconductive materials for underground power transmission. Specimens were made of sheet form with the three of existing resins and the nine of specimens for measurement. Impurities content of specimens was measured by ICP-AES(Inductively Coupled Plasma Atomic Emission Spectrometer), and density of specimens were measured by density meter. And then heat capacity(${\Delta}H$) and melting temperature(Tm), specific heat(Cp) were measured by DSC(Differential Scanning Calorimetry). The dimension of measurement temperature was $0[^{\circ}C]\;to\;200[^{\circ}C]$, and rising temperature was $4[^{\circ}C/min]$. Impurities content was highly measured according to increasing the content of carbon black from this experimental result also density was increased according to these properties. Specially, impurities content values of the A1 and A2 of existing resins were measured more than 4000[ppm]. Heat capacity, melting temperature, and specific heat from the DSC results were simultaneously decreased according to increasing the content of carbon black. Because metallic impurities of carbon black having Fe, Co, Mn, A1 and Zn are rapidly passed kinetic energy increasing the number of times breaking during the unit time with the near particles according to increasing vibration of particles by the applied heat energy.

• The Korean Journal of Food And Nutrition
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• v.35 no.4
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• pp.239-246
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• 2022

In this study, the dietary fiber content of 33 kinds of agricultural products and seaweeds was compared with that of raw products after heat treatment. To verify the total dietary fiber analysis method, the recovery rate was reviewed by measuring the total dietary fiber content for 4 standard certified substances. As a result, the recovery rate of the analysis value for the true value was 98.8%~103.1%, which was judged to be reliable. The total dietary fiber of vegetables ranged between 0.61~5.36 g/100 g for raw vegetables and 0.55~4.84 g/100 g for heat-treated vegetables. Among the 24 kinds of vegetables used in the analanalysis, the total dietary fiber content of heat-treated Korean radish (3.13 g/100 g) was the highest compared to that of raw radish (0.61 g/100 g). The total dietary fiber of beans was between 13.86~29.69 g/100 g for raw beans and 6.72~18.40 g/100 g for heat-treated beans. In particular, the total dietary fiber content of sword beans was the highest in both raw (29.69 g/100 g) and boiled (18.40 g/100 g) beans. The total dietary fiber content of the three types of seaweed was 1.93~4.85 g/100 g in raw seaweed and 0.99~5.72 g/100 g in heat-treated seaweed.

• Journal of Welding and Joining
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• v.6 no.2
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• pp.40-46
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• 1988

The effect of heat input on the content of residual .delta.-ferrite and the hot cracking susceptibility in the austenitic stainless steel overlaid on the carbon steel was studied in the range of heat input from 7.5 to 15.1 KJ/cm. Present study shows that residual .delta.-ferrite content in the overlay is mainly determined by the dilution of the base metal (carbon steel) which is in turn affected by heat input, i.e. the amount of dilution decreases as heat input increase. Accordingly, higher heat input results in a substantial increase in Cr equivalent but a little increase in Ni equivalent due to the less dilution of carbon from base metal. This fact can explain the result obtained in this study, i, e, the higher content of .delta.-ferrite in the weld deposit made with higher heat input. This in turn causes more resistant overlaying weld metal to hot cracking.

• 한국해양학회지
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• v.20 no.3
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• pp.1-5
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• 1985

Seasonal variations of heat content in the neighbouring seas of Korea are estimated from the bimonthly normals of seawater temperature in the upper 300m for 15 years (1961~1975) at 192 stations. The heat is seasonally stored mainly in the upper 100m layer in the East Sea and in the whole water column in the West and South Seas of Korea. The annual range of heat content changes in the West Sea is almost the same as that in the East Sea. The annual phase of heat content variation lags behind that of sea surface temperature variation by one to three months. Due to the seasonal advections of heat by currents and winds, the annual amplitude of heat storage rate in the neighbouring seas of Korea is much larger than that of incoming radiation.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.633-636
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• 2006

The purpose of this study was to measure the heat resistance and core mineral content of Geobacillus stearothermophilus ATCC 7953 spores when the sporulating cells were exposed to heat shock at different times during sporulation. Heat shock during sporulation was found to increase the heat resistance of the spores produced subsequently. The spores heat shocked 2 h after the end of the exponential phase showed the highest heat resistance and a 3D-fold increase in the $d_{10}$ compared with the non-heat-shocked spores. The enhanced heat resistance was likely due to the increased mineral content observed in the spores heat shocked at $t_7\;or\;t_8$.