• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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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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• 한국가스학회 1997년도 추계학술발표회 논문집
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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.

• 문화기술의 융합
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• 제7권2호
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• pp.443-451
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• 2021

이 연구는 재선충 감염 소나무와 비 감염 소나무의 수분함유율에 따른 연소열 실험을 통해 열적특성을 비교 분석하였다. 실험 결과는 다음과 같다. 수분 함유율 분석 결과는 재선충 감염 소나무의 경우 평균 19.92%, 비 감염 소나무는 26.27%로 화재 시 전도, 대류, 복사열 크기가 커질수록 수분 함유량이 감소한다. 수분 함유량의 기화가 가속되면 평형 수분 함유율에 도달하고 수분 함유율이 15%이하에서는 열원에 의하여 착화되지 않는다는 목재의 열적 특성에 상반되는 결과이다. 연소열 분석 결과는 재선충 감염 소나무와 비 감염 소나무는 연소열은 약 3%로 큰 차이를 보이지 않았다. 하지만 연소열이 다른 수종에 비해서는 높은 수치를 나타낸다는 것을 알 수 있다. 결론적으로 전도, 대류, 복사열의 증가에 따른 수분 함유율의 감소가 착화에 직접적인 원인 중 하나이며 수분 함유량이 감소할 수록 화재 확산 속도도 빨라진다는 것을 알 수 있었다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권12호
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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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• 제18권1호
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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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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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.

• 한국식품영양학회지
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• 제35권4호
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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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• 제6권2호
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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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• 제20권3호
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• pp.1-5
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• 1985

한국주변 192개 정점 표층 300m의 15년간(1961~1975) 격월 수온자료를 사용하여 해양이 보유(방출)하는 영량의 계절적인 변동을 추정하였다. 동해에서는 100m 이내의 표층에서 계절적인 열의 보관과 방출이 일어나며, 수심이 얕은 서해와 남해에서는 거의 전 수심에 걸쳐서 계절적인 열보유량 변동의 연교차는 서해와 동해가 비슷하나, 열보유량 변동은 표면수온에 비하여 연주기 위상이 1내지 3개월 늦다. 해류와 계절풍에 의한 열이송으로 인하여 한국주변 해양 저열량의 시간적 변화의 연진폭은 태양복사에너지의 연진폭보다 훨씬 크다.

• Journal of Microbiology and Biotechnology
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• 제16권4호
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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 $t_7\;or\;t_8$.