• Elastomers and Composites
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• 제48권4호
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• pp.276-281
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• 2013

acrylic polyol로 개질한 polyester형 polyurethane foam을 quasi prepolymer법으로 제조하였다. 열적 및 동적 기계적 성질은 thermal gravimetric analysis 및 dynamic mechanical analysis에 의하여 분석하였다. 또한 유리전이온도는 differential scanning calorimeter로 측정하였다. Acrylic polyol 함량이 증가함에 따라 TGA에 의해 측정한 열적 안정성은 약간 감소하였다. 그리고 acrylic polyol 함량이 증가함에 따라 저장 탄성률은 증가한 반면에 tan delta 값은 감소하였다.

• 한국연소학회지
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• 제16권3호
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• pp.21-26
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• 2011

Thermal analyses are conducted to measure chemical kinetic parameters of an unknown liquid fuel with various components. Thermal Analyses are divided into two different methods such as TGA(Thermo-Gravimetric Analysis) and DSC(Differential Scanning Calorimety). Non-isothermal experimental results are analyzed by adopting TGA and they are filtered by Freeman-Carroll method. As a results of the analysis, chemical parameters of the activation temperature and the reaction order are measured to be 6128.2 K and 1.4, respectively. Furthermore, the chemical kinetic parameters are obtained by a variety of mathematical processing methods. It has been found that they show a little difference depending on the processing method.

• 한국안전학회지
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• 제34권4호
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• pp.32-40
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• 2019

During the manufacturing process of a printed circuit board(PCB), fumes and mists are generated as the ink dries on the PCB surface. The generated fumes and mists are deposited in the dryer wall and the exhaust duct. Deposited fumes and mists may present a fire hazard if the dryer temperature control system fails. In this study, the thermal stability of the fumes and mists deposited in the dryer and ducts has been analyzed by experimental methods such as thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), auto ignition temperature (AIT), and multiple mode calorimetry(MMC). According to the experimental analyses, experimental samples are likely to generate gas at the temperature ($180{\sim}240^{\circ}C$) that deviates from the normal operating temperature ($150{\sim}156^{\circ}C$). It has been shown that the thermal stability is degraded when the temperature is deviated from the normal operating temperature. In the end, engineering and management safety measures of accidental prevention have been suggested.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.317-318
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• 2023

This study is part of the carbonation degree DB accumulation through quantitative analysis of carbonation depth, Ca(OH)₂ and CO₂ according to the type of finish and years of use of old concrete structures in order to predict the amount of CO₂ that can be absorbed through carbonation of concrete. To this end, the depth of carbonation of the concrete core specimen is measured using an indicator, and the dry amount of water combined with CO₂ in the sample is measured using a differential thermal gravimetric analyzer for samples in the carbonation area and non-carbonated area classified by the indicator, and the absorption compared to the weight of the sample. The amount of absorbed CO₂ was calculated. In addition, the degree of carbonation was calculated through quantitative comparison of Ca(OH)₂ in the carbonation section and non-carbonation section. In the future, we will continue to add the survey and analysis data of dismantled structures and use them as basic data for estimating the amount of carbon dioxide that can be absorbed according to the exposure conditions and years of use by concrete mix.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제36회 춘계학술대회논문집
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• pp.421-424
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• 2011

본 연구에서는 열분석법을 이용하여 혼합 액체연료의 수치해석에 필요한 여러 가지 인자를 측정하였다. 이러한 열분석법에는 열중량 분석방법(TGA, Thermo-Gravimetric Analyzer)과 시차 주사열량 측정법(DSC, Differential Scanning Calorimetry)이 있다. 열중량 분석방법을 통한 비등온 실험(non-isothermal experimental) 결과를 토대로 Freeman Carroll의 수학적인 후처리 방법을 이용하여 미지의 액체연료의 구성 성분에 대한 동역학적 변수인 활성화 온도와 반응차수로 각각 6128.2 K와 1.4를 얻었다. 그 외 다양한 수학적 처리 방법에 따른 동역학적 변수의 값을 구해보았고, 계산 결과는 처리방법에 따라 약간의 차이를 보였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.197-198
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• 2022

Based on the carbonation depth measurement by the indicator for concrete collected from old structures and the quantitative analysis of Ca(OH)₂ and CO₂ in the carbonation section before and after the carbonation depth and in the non-carbonation section, the absorbable CO2 amount and carbonation degree measurement result is as follows 1) The carbonation depth of the 40-year-old reinforced concrete structure was measured to be about 22 mm. (basement interior wall, marble finish, strength 30MPa) 2) The amount of CO₂ absorbed by the concrete was about 4.3% of the sample weight, and the carbonation degree was estimated to be about 53%.

• Bulletin of the Korean Chemical Society
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• 제30권3호
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• pp.618-622
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• 2009

The new candidates for OTFTs, which were composed of naphthalene, anthracene, benzo[1,2-b:4,5-b’]dithiophene and 2-decylbithiophene end-capper were synthesized under Suzuki coupling reaction conditions. All of the oligomers were characterized by FT-IR, mass analysis, UV-vis, PL spectrum, cyclic voltametry (CV), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), $^1H-NMR\;and\;^{13}C-NMR$. Investigation of physical properties showed that all of the oligomers have higher oxidation potential and good thermal stability. Especially, DBT-DtB-DBT is soluble in common solvents and suitable for low cost processing technologies.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(3)
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• pp.403-408
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• 1996

석탄화력발전소 폐기물인 석탄회와 요오드화 세슘의 반응특성을 DTA(Differential Thermal Analysis), TGA(Thermo-Gravimetric Analysis) 장치를 이용하여 분석하였다. 본연구에 사용된 석탄회는 85%의 실리카와 알루미나를 함유하고 있으며 Si/Al 몰비는 2.1 이었다. DTA와 TGA의 열분석 결과 CsI의 분해, 석탄회와 기체상 세슘의 반응 등으로 이루어져 있다. 석탄회와 CsI의 혼합물은 94$0^{\circ}C$ 이상에서 Pollucite 가 형성되었다. 반응생성물들의 SEM 분석결과 표면이 거칠며 bulky한 crystal 형태로서 구형의 석탄회와는 매우 다른 형상을 보였다. 석탄회는 요오드화세슘의 고정화를 위해서 적합한 알루미노규산염 원료물질들 중의 하나임을 확인하였다.

• Applied Microscopy
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• 제50권
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• pp.12.1-12.11
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• 2020

Hot stage microscopy (HSM) is a thermal analysis technique that combines the best properties of thermal analysis and microscopy. HSM is rapidly gaining interest in pharmaceuticals as well as in other fields as a regular characterization technique. In pharmaceuticals HSM is used to support differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA) observations and to detect small changes in the sample that may be missed by DSC and TGA during a thermal experiment. Study of various physical and chemical properties such sample morphology, crystalline nature, polymorphism, desolvation, miscibility, melting, solid state transitions and incompatibility between various pharmaceutical compounds can be carried out using HSM. HSM is also widely used to screen cocrystals, excipients and polymers for solid dispersions. With the advancements in research methodologies, it is now possible to use HSM in conjunction with other characterization techniques such as Fourier transform infrared spectroscopy (FTIR), DSC, Raman spectroscopy, scanning electron microscopy (SEM) which may have additional benefits over traditional characterization techniques for rapid and comprehensive solid state characterization.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.773-778
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• 2002

The variance characteristics of the calcium carbonate contents along to the concrete cover depth takes the prediction method of remaining service life of concrete. Calcium carbonate contents were measured by the Thermo Gravimetric/Differential Thermal Analysis method at three point, depth of 0.25cm, 0.75cm, 1.25cm from the surface of concrete. This prediction method contain some assumption that the chemical protection conferred on steel is through a passive protective oxide film which forms on steel in an environment at or above a pH of 10.5$^{4)}$ .