• Journal of Power System Engineering
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• v.20 no.4
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• pp.38-43
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• 2016

Safety-related equipments of Nuclear Power Plants(NPP) have to perform environmental qualification test in accordance with IEEE-323 standards. However, non-metallic materials replace new one regularly instead of the test because they are considered as consumable parts. In this study, the seven kinds of non-metallic materials are selected and their activation energy was experimentally evaluated with uncertainty analysis by using thermogravimetric analyzer(TGA). In order to obtain activation energy of non-metallic materials, mass difference, temperature raising rate and conversion rate on the specimen are analyzed. It is postulated that the three experiment conditions are important to get a reliable activation energy. This postulate was experimentally confirmed using Arrhenius equation and Flynn-Wall-Ozawa analysis.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.410-411
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• 2009

The multi-component ceramic proton conductor, $BaZr(Y)O_3-SiO_2-TiO_2-ZrO_2$ (BZY-STZ) and $LaPO_4-SiO_2-TiO_2-ZrO_2$ (LP-STZ), were synthesized by micro-emersion and sol-gel technique. The characterization of proton conductors were carried out using X-ray diffraction(XRD), thermogravimetric analysis(TGA), differential thermal analysis(DTA), impedance analysis. The proton conductors indicate the possibility of application for the intermediate temperature up to $700^{\circ}C$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.330-333
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• 1997

The thermal impact of mica/epoxy paper(130${\mu}{\textrm}{m}$) is investigated using XRD, DSC and TGL X-ray diffraction(XRD) analysis was performed to know the position and structure of mica crystal in insulation materials. A differential scanning calorimeter(DSC) was used to measure glass transition temperature and excess enthalphy of the composite materials that had been subjected to thermal aging. The glass transition temperature(T$_{g}$) measured by DSC is observed at 95.43$^{\circ}C$ and 113.43$^{\circ}C$, respectively. The T$_{g}$ also increases with increased aging time. Measurements performed by TGA(thermogravimetric analysis) have showed that weight loss profile of sound specimens are lower than those aged.ged.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2617-2622
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• 2011

Two new Zn(II) complexes, $[Zn_2(dpa)_2(phen)_2(H_2O)_2]{\cdot}H_2O$ (1) (dpa = dephenate, phen = 1,10-phenanthroline) and [$Zn_2(dpa)_2(bpy)_2(H_2O)_2$] (2) (bpy = 2,2'-bipyridine) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The X-ray analysis reveals that the structures of 1 and 2 are dinuclear zinc(II) complexes bridged by dpa dianions, respectively. The zinc ions in 1 exhibit a distorted square pyramidal environments, while the zinc ions in 2 exhibit a trigonal bipyramid geometry. In each complex, the dpa ligand is coordinated to zinc ions as a bis-monodentate.

• Fibers and Polymers
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• v.3 no.2
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• pp.55-59
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• 2002

The thermal reaction of acetoacetanilide in the presence of aniline or phenol yielded carbanilide in quantitative yields. This reaction was applied to the synthesis of polyurea. Bisacetoacetamides were prepared from diamines and diketene in DMF. They were thermally polymerized in the presence of phenol or a diamine (6FDA) to yield polyureas of low molecular weights. The polymers were soluble in DMSO and NMP. $^1{H-NMR}$ analysis showed that they had amino group terminated structures. Poly(urea-imide) was synthesized by the reaction of an oligourea diamine with pyromellitic dianhydride in NMP. The concentration of terminal amino groups was determined by an acid-base titration. The thermal property of poly(urea-imide) was evaluated by thermogravimetric analysis (TGA). Initial decompisition took place at 332-$350^{\circ}C$.

• Nano
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• v.13 no.12
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• pp.1850143.1-1850143.9
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• 2018

Natural biotemplates - such as bacteria, fungi and viruses - are used in nanostructured metal oxide production. The pollen can be found abundantly in nature, and their microcapsules can be easily isolated from the pollen by chemical treatments. To date, pollen microcapsules are mostly used as drug carriers and catalytic agent templates. In the present study, nanoporous-structured nickel oxide is produced using Pistachio pollen microcapsules. The raw pollen, chemically treated pollen and metal-coated pollen were characterized using scanning electron microscopy, Brunauer-Emmett-Teller (BET) surface area analysis, thermogravimetric analysis (TGA), differential thermal analysis (DTA) and X-ray diffraction (XRD) techniques. The natural Pistachio pollen which were procured from Gaziantep, Turkey, are spherical, with a diameter of approximately $23{\mu}m$. The maximum surface area obtained for nickel oxide-coated microcapsules is $228.82m^2/g$. This result shows that Pistachio pollen are an excellent candidate for the production of porous nanostructured materials for supercapacitor electrodes.

• Fire Science and Engineering
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• v.33 no.2
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• pp.1-8
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• 2019

This study was conducted to investigate the possibility of spontaneous ignition in Butadiene popcorn polymer, which is used as raw material and product in a chemical plant. A component analysis, thermogravimetric analysis, thermal stability analysis, spontaneous ignition point measurement and accelerated velocity calorimetric analysis were performed. As a result of analysis, various kinds of flammable components were measured and thermogravimetric analysis showed a weight loss of 95.6% in air and 89.2% in nitrogen. As a result of the thermal stability analysis, heat generation started at $88^{\circ}C$ in the air atmosphere, and the heat generation rate increased sharply in the vicinity of the natural ignition point ($220^{\circ}C$). The heat generation started at about $70^{\circ}C$ in nitrogen atmosphere, and the two exothermic peak values were observed up to $450^{\circ}C$. As a result of accelerated rate calorimetry, there was no exothermic phenomenon, and the lowest ignition temperature was $211.7^{\circ}C$ as a result of analysis of natural ignition point. Based on the results obtained from the thermal stability evaluation, it is considered that the possibility of inducing the thermal deformation of the column by the heat of reaction is sufficient.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.554-563
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• 2016

Ships are capable of operating on residual fuel oil. Recently, various attempts have been made to meet environmental regulations and with ships operating on residual fuel oil. One way of fulfilling these requirements is by using fuel additives. Dispersants and fuel combustion improvers will have a positive effect on improving the combustion characteristics of the residual fuel oil. As such, this study examines fuel oils blended with additives by using fuel combustion analysis (FIA/FCA) and thermogravimetric analysis (TGA). The results of FIA/FCA focuse only on the amount of work done by the fuel oil. Therefore, it is recommended in this study that a new method to evaluate the combustion efficiency via FIA/FCA processes be developed. The analysis with ROHR curve gained by FIA/FCA brought similar results with pressure trace curve therefore it can be said that new analysis method can be reliable. The TGA, analysis process is very sensitive to the evaporation of fuel, for example, which could be addressed. In the performance-related findings of this study, blended samples with additives containing iron compounds showed a greater improvement in early combustion characteristics than samples without additives.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.391-397
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• 2012

The depletion of conventional oil reserves and the increasing energy need in developing countries such as China and India result in exceeding oil demand over supply. As a solution of the problem, the efficient utilization of heavy oil has been receiving more and more interest. In order to utilize heavy oil, upgrading processes are required. Among the upgrading processes, thermal decomposition is thought to be relatively simple and economical. In this study, to understand basic characteristics of thermal decomposition of heavy oil, we conducted pyrolysis experiments of deasphalted oil (DAO) produced by a solvent deasphalting process. DAO is a mixture of many components and consists mainly of materials of carbon number 20~40. For the comparison with results of DAO pyrolysis, additional pyrolysis experiments with single materials of carbon number 30 ($C_{30}H_{62}$, $C_{30}H_{58}O_4S$, $C_{30}H_{63}O_3P$) were conducted. Pyrolysis experiments were carried out non-isothermally with variation of heating rate (10, 50, $100^{\circ}C$/min) in a thermogravimetric analyzer. Average pyrolysis activation energy determined by using Arrhenius method, Ingraham and Marrier method, and Coats and Redfern method was 72~99 kJ/mol. In the activation energy calculated by Ozawa-Flynn-Wall method, DAO had wider variation than other single materials.

• Journal of Adhesion and Interface
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• v.18 no.2
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• pp.68-74
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• 2017

Epoxy resins are widely used in various fields due to their excellent thermal, mechanical and chemical properties. In order to improve the mechanical properties of the epoxy composition after curing, various materials are mixed in the epoxy resin. Among the nano materials, CNT is the most widely used. However, CNT has limitations in terms of manufacturing process and manufacturing cost. Therefore, there is a growing interest in naturally occurring HNTs having similar structure to that of CNT. In this study, the thermal and mechanical properties of epoxy compositions containing HNTs treated with two types of silane compounds were investigated. The mechanical properties of silane-treated HNT were measured by using a universal testing machine. The differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), and thermomechanical analysis (TMA) were used to measure thermal properties. As a result of the above tests, when the HNT was surface-treated with aminosilane, the tensile strength of the epoxy composition containing the HNT was higher than that of the epoxy composition containing epoxy silane treated HNT. The linear thermal expansion coefficients (CTE) obtained from the thermomechanical analysis of the two epoxy compositions for the comparison of dimensional stability showed that the HNT composition treated with aminosilane showed a lower value of CTE than that of epoxy composition including the pristine HNT.