• Title/Summary/Keyword: Thermogravimetric Analysis

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Quantitative Evaluation of Non-Carbon Content in the Single Wall Carbon Nanotube Soot using Thermogravimetric Analysis

  • Han, J.H.;An, K.H.;Lee, N.S.;Goak, J.C.;Jeong, M.S.;Choi, Y.C.;Oh, K.H.;Kim, K.K.;Lee, Y.H.
    • Carbon letters
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    • v.10 no.1
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    • pp.5-8
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    • 2009
  • We measured the non-carbon content of single-walled carbon nanotubes (SWCNTs) in SWCNT soot using thermogravimetric analysis. The weight increased percentage by the oxidation of metal in the raw soot is well obtained by TGA graph which was confirmed with ICP-AES, XRD, and XPS. This work will be very useful for the purity precise evaluation of SWCNT with UN-vis-NIR spectroscopy.

Thermal Decomposition of Phase Stabilized Ammonium Nitrate (PSAN) (상안정화 질산암모늄(PSAN)의 열분해)

  • 김준형;임유진
    • Journal of the Korean Society of Propulsion Engineers
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    • v.3 no.4
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    • pp.23-30
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    • 1999
  • The thermal decomposition of phase stabilized ammonium nitrate(PSAN) was studied by means of thermogravimetric analysis(TGA). In this study, potassium nitrate and zinc oxide were used as the phase stabilizers in the range of contents from 0 wt.% to 8 wt.%. The kinetics and mechanism for the decomposition were evaluated using integral methods. It was found that the thermal kinetic parameters such as activation energy(I) and frequency factor(A) increase with the increase of the stabilizer contents, and the mechanism of decomposition also changes.

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Assessment of Particulate Matters from an Exhaust Gas for Conventional and Low Temperature Diesel Combustion in a Compression Ignition Engine (압축 착화 엔진에서 기존 및 저온 디젤 연소에서 발생하는 배기가스의 입자상 물질에 관한 특성 비교)

  • Jung, Yongjin;Shin, Hyun Dong;Bae, Choongsik
    • 한국연소학회:학술대회논문집
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    • 2012.11a
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    • pp.183-186
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    • 2012
  • The characteristics of particulate matters (PM) from an exhaust gas for conventional and low temperature diesel combustion (LTC) in a compression ignition engine was experimentally investigated by the elemental, thermogravimetric analysis. Morphology of PM was also studied by the transmission electron microscopy. PM for LTC shows that it contains more volatile hydrocarbons, which can be easily evaporated than conventional regime. PM for LTC is comprised of smaller primary particles.

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Crystal Forms of Ketorolac

  • Sohn, Young-Taek;Seo, Hyun-Ok
    • Archives of Pharmacal Research
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    • v.27 no.3
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    • pp.357-360
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    • 2004
  • Four crystal forms of ketorolac have been obtained by recrystallization in organic solvents under variable conditions. Different ketorolac polymorphs and pseudo polymorph were characterized by X-ray powder diffraction crystallography (XRD), Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). In the dissolution studies in water at $37{\pm}0.5^{\circ}C$ four crystal forms showed different patterns. The solubility of Form I were the highest. The solubility decreased in rank order: Form I> Form II > Form III > Form IV. Form land Form III were shown to have a good physical stability at room temperature for 60 days. However, Form II is converted to Form III and Form IV is converted to Form I after 60 days storage. Therefore, these observations indicate that crystalline polymorphism for ketorolac is readily inter-convertible and the relationship may have to taken into consideration in the formulation of the drug.

Thermal Characteristics of Polypropylene in Combustion Reaction Using TGA (TGA를 이용한 폴리프로필렌의 연소반응에서의 열적 특성 연구)

  • Kang, Yun-Jin;Seo, Su-Eun;Seo, Gyu-Suk;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
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    • v.10 no.4
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    • pp.111-120
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    • 2008
  • The combustion reaction of polypropylene was investigated using a thermogravimetric technique under an air atmosphere condition at several heating rates from 10 to $50^{\circ}C/min$. To obtain information on the kinetic parameters, the dynamic thermogravimetric analysis curve and its derivative were analyzed by a variety of analytical methods such as Kissinger, Friedman, Freeman-Carroll, Chatterjee-Conrad, Ozawa and Coats-Redfern methods. The comparative works for the kinetic results obtained from various methods should be performed to determine the kinetic parameters, because there are tremendous differences in the calculated kinetic parameters depending upon the mathematical method taken in the analysis.

Synthesis, Characterization, and the Influence of Functionalized Multi-Walled Carbon Nanotubes with Creatinine and 2-Aminobenzophenone on the Gastric Cancer Cells

  • Tahermansouri, Hasan;Aryanfar, Yaser;Biazar, Esmaeil
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.149-153
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    • 2013
  • The chemical functionalization of carboxylated multi-walled carbon nanotubes (MWCNT-COOH) by creatinine (MWCNT-Amide) and latter modification with 2-aminobenzophenone for producing 1-methyl-9-phenyl-1H-imidazo[4,5-b]quinolin-2-amine (MWCNT-quino) have been investigated. All products were characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscope, elemental analysis, thermogravimetric analysis, derivative thermogravimetric and cellular investigations. The interesting point is that MWCNT-quino can be homogeneously dispersed in dimethylformamide and to some extent in ethyl alcohol without sonication. Also, MTT assay was used to examine the behavior of cell proliferation after 48 h of cell culture experiments. Cellular results showed high toxicity of MWCNT-quino on the cancer cells. These functionalizations have been chosen due to active sites of carbonyl and methylene groups in MWCNT-Amide and the creating quinoline derivative on the MWCNTs for future application.

A Study on the Dielectric Properties of Silicone Rubber due to Hardness Variation (경도 변화에 따른 실리콘 고무의 유전 특성에 관한 연구)

  • Lee, Sung-Ill
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.25 no.11
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    • pp.916-921
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    • 2012
  • This research measured the dielectric properties of silicone rubber with various hardness in 100 Hz~3 MHz, $30{\sim}170^{\circ}C$ conditions. When the hardness increases from 65 degree to 75 degree, the dielectric loss increased within frequency range of 100 kHz~3 MHz and was a little change in dielectric loss within temperature range of $90^{\circ}C{\sim}170^{\circ}C$. Thermogravimetric Analysis (TGA) showed the weight change rate increased a little while heated until $800^{\circ}C$. Scanning Electron Microscope (SEM) measurement showed that Aluminium Trihydroxide($AlOH_3$) which acts as a reinforcement agent reduced the size of the particles as the hardness increased.

Asessment of Fire Damage Depth of 21MPa-class Concrete Using Thermogravimetric Analysis (열중량분석을 활용한 21MPa급 콘크리트의 화해피해깊이 진단방법 분석)

  • Lim, Gun Su;Han, Soo Hwan;Han, Jun Hui;Yoon, Chee Whan;Han, Min Cheol;Han, Cheon Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.243-244
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    • 2021
  • In this study, we develop diagnostic technology for damage depth of fire-damaged concrete and propose methods for damage caused by fire by drying damaged concrete after immersion. As a result of the test, the damaged depth was clearly found when evaluating the depth of impurities caused by fire in a drying method after water had permeated, and it could be verified using thermogravimetric analysis.

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Effects of Oxidation Process on Thermal Properties of Petroleum-based Isotropic Pitch (산화 공정이 석유계 등방성 피치의 열거동 특성에 미치는 영향)

  • Lee, Namji;Seo, Sang Wan;Kwak, Cheol Hwan;Kim, Min Il;Im, Ji Sun
    • Applied Chemistry for Engineering
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    • v.31 no.1
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    • pp.36-42
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    • 2020
  • In order to investigate the effect of the oxidation process on thermal properties of the pitch, the oxidized pitch was prepared by changing the oxidation temperature. Thermal properties of the pitch were analyzed using thermogravimetric analysis (TGA), and it divided into three sections as A (25~100 ℃), B (250~550 ℃) and C (550~800 ℃) by derivative thermogravimetry (DTG) graph behavior. In the A section, the was reduced because the moisture contained in the pitch was removed. In the B section, as the oxidation temperature increased, the thermal stability of the pitch is improved. Because the degree of aromaticity and molecular weight of the pitch increased with increasing oxidation temperature. In contrast, the results of the C section were shown opposite of B section. Because the introduced C-OH, C-O-C, and C=O bonds were decomposed, and the resulting oxygen compounds induced the combustion reaction of the pitch.