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used and demonstrate that thermogravimetry (TG) can be a good replacement for these methods. Sampling and current analysis techniques As CFR sect. 211.67 states, “Equipment and utensils shall be cleaned, maintained, and

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Journal of Thermal Analysis and Calorimetry
Authors: A. J. D. Fernandes, J. H. P. Barbosa, O. G. Silva, M. G. Fonseca, L. H. N. Arakaki, and J. G. P. Espínola

characterization was done by X-ray diffractometry (XRD), infrared (IR) spectroscopy, thermogravimetry (TG) and nuclear magnetic resonance ( 29 Si NMR). The chemical stability was implemented for pH varying at 1.0–6.0. Methods and materials

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, AS , Barros , JMF , Pedrosa , AMG , VJ Fernandes Jr , Souza , MJB . Thermogravimetry applied to characterization of SBA15 nanostructured material . J Therm Anal Calorim . 2007 ; 87 : 457 – 461 . 10.1007/s10973

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evaluate of the vapor pressure of the curves of warifteine and methylwarifteine using thermogravimetry analysis. Methods and materials Methylparaben (reference) was purchased from Dinalab (NF00222). Warifteine and

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Abstract  

Naphthenates are produced when naphthenic acids present in crude oil are mixed with brine. They deposit at oil/water interface and are insoluble in either of the phases causing a large problem to the oil industry. Generally, naphthenates precipitate jointly with others compounds such as sulfates and carbonates. This fact makes difficult their characterization. In this study, calcium stearate formation from stearic acid was investigated, under different conditions, as a previous model to understanding of calcium naphthenate precipitation. Medium reactions distinct were studied and the results indicated that the ethanol medium was the most efficient for the formation of solids because in this only case, the stearic acid was completely converted into stearate. Monitoring of the conversion was performed by thermogravimetry in spite of this technique not be typical in salts characterization. Nevertheless, the thermogravimetric analysis showed that is possible to identify differences between an organic acid, a salt of this acid and an inorganic salt, in the same sample. Infrared spectra was used in order to confirm the results obtained by thermogravimetry. However, this technique showed less efficiency and sensibility.

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-skimmer technology was used for direct sampling of evolved gases from thermogravimetry (TG) in conjunction with a time-of-flight mass spectrometric detection (TOFMS) and a photo ionisation with VUV light (single photon ionisation, SPI). Furthermore an innovative VUV

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Journal of Thermal Analysis and Calorimetry
Authors: F. M. Aquino, D. M. A. Melo, R. C. Santiago, M. A. F. Melo, A. E. Martinelli, J. C. O. Freitas, and L. C. B. Araújo

developed to determine some kinetic parameters. In these studies, the most-used thermal analysis techniques are thermogravimetric analysis (TG) and differential thermal analysis (DTA) [ 6 ]. Thermogravimetry is a technique in which the mass of a substance is

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Abstract  

The objective of this research was to investigate the effect of different clay composition and concentrations on the thermal behaviour and kinetics of heavy crude oil in limestone matrix by thermogravimetry (TG/DTG). In TG/DTG experiments, three distinct reaction regions were identified in all of the crude oil + limestone mixture known as low temperature oxidation (LTO), fuel deposition (FD) and high temperature oxidation (HTO) respectively. Addition of clay to porous matrix significantly affected the reaction regions. Significant reduction of activation energy due to addition of clay to crude oil indicates the catalytic effect of clay on crude oil combustion.

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Abstract  

The potential of hyphenating thermogravimetry (TG) and soft photo ionisation mass spectrometry (EBEL-SPI-MS) for fundamental and applied research and material analysis has been demonstrated by a newly developed TG-SPI quadrupole MS coupling (TG-SPI-QMS). Thermal decomposition of three common plastics, polyethylene (PE), polystyrene (PS) and polyvinylchloride (PVC) has been studied. While the decomposition of PE and PS in inert atmosphere takes place in a one step process (main mass loss at about 490 and 420 °C, respectively), PVC decomposes in a two step mechanism. The organic signature of the PE decomposition shows homologous series of alkenes and polyenes, while PS is forming mainly styrene mono- and oligomers. In the PVC decomposition, firstly hydrogen chloride (HCl) is eliminated in a hydro-dechlorination reaction (1st mass loss step: 285–305 °C), this is accompanied by the emission of the carbon skeletons of small aromatics (predominately benzene and naphthalene). In the second step (2nd mass loss step: 490–510 °C), the residual cross-linked polyolefin moieties decompose under release of heavily alkylated aromatics, including larger PAH. Chlorinated aromatics are formed only in trace levels.

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using thermogravimetry (TG) of water desorption as main method for the mass analysis of intercalated compounds [ 18 – 20 ]. Experimental Layered oxides NaLnTiO 4 (Ln = Nd, La) and CsNdTa 2 O 7 were prepared by conventional

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