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Abstract  

KDNBF (potassium 4,6-dinitrobenzofuroxan) has been used as a primer explosive in igniters and detonators for many years. Considerable information about the sensitivity of KDNBF to various stimuli, such as impact, friction, shock and electrostatic charge, is known. However, the thermal sensitivity of KDNBF has been relatively unexplored. Hence, there is very little information available concerning the fundamental thermal properties of KDNBF. Therefore, as part of an extensive thermal hazard assessment, DSC, TG, accelerating rate calorimetry (ARC) and heat flux calorimetry (HFC) measurements have been undertaken on KDNBF. The results demonstrate that KDNBF decomposes via a multi-step exothermic process directly from the solid state. The decomposition process does not appear to depend on the nature of the atmosphere, except in the final stage of the TG decomposition in air, where remaining carbonaceous material is converted to CO2. The first stage of the decomposition is sufficiently rapid that ignition occurs if too large a sample is used. Dynamic and isothermal methods were used to obtain the kinetic parameters and a range of activation energies were obtained, depending on the experimental conditions. The kinetic results have been analyzed in terms of various solid state decomposition models.

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.A. Landis 1971 Graphitization of dispersed carbonaceous material in metamorphic rocks Contribution to Mineralogy and Petrology 30 34 35

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Abstract  

Four commercial Saudi Arabian crude oils were characterized by thermogravimetry (TG) and differential thermal analysis (DTA). These crude oils, Arab Berri (AB), Arab Light (AL), Arab Medium (AM) and Arab Heavy (AH), were also subjected to the traditionally employed true boiling point (TBP) distillation and simulated distillation (SIMDIST). The TG/DTA data show that the hydrocarbons present in these crude oils fall into four groups: the volatiles, the low molecular weight, the medium molecular weight and the high molecular weight compounds. These four types of hydrocarbons were observed to display certain trends, such that the volatile and low molecular weight hydrocarbons increased, while the medium and high molecular weight hydrocarbons decreased with the lightness of the crude. The volatile contents of AB, AL, AM and AH crude oils up to 280�C were 50.1, 42.2, 42.3 and 38.5 mass percent, respectively. This confirms that AB is the lightest of these crude oils with maximum volatile content. The mass percentage loss from the TG results is in good agreement with the percentage distilled from TBP (ASTM D 2892) and SIMDIST. During evaporation, the TG mass loss follows a similar trend to those of the TBP and SIMDIST results and thus behaves like distillation. During the oxidative degradation, the TG curve shows a higher mass loss as compared to the distillation data. The higher deviation of the TG mass loss and percentage distilled at the higher-temperature end of the curve may be attributed to the higher content of asphaltenes and carbonaceous material present in AH as compared to the AB crude oil. At around 200�C, the TG mass loss curve intersects the TBP and SIMDIST curves and shows a derivation from distillation behaviour. This intersection temperature of the TG and distillation curves is observed to decrease with the heaviness of the crude and can be an indication of the onset of thermal degradation of hydrocarbons present in the crude oil. On the whole, the TG data closely resemble the distillation results.

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Co-firing of biomass with coals

Part 2. Thermogravimetric kinetic analysis of co-combustion of fir (Abies bornmulleriana) wood with Beypazari lignite

Journal of Thermal Analysis and Calorimetry
Authors: Sinem Taş and Yuda Yürüm

considered as a good approach for the investigation of combustion kinetics of carbonaceous material, as the dependence of conversion on activation energy is crucial to explore the mechanism and kinetics of decomposition process. According to observations

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Journal of Thermal Analysis and Calorimetry
Authors: Cheila G. Mothé, Michelle G. Mothé, Alan T. Riga, and Kenneth S. Alexander

inorganic substances or carbonaceous material. DTG curve shows some degradation stages at 300–400 °C and DTA thermogram shows two endothermic events close to 230 and 310 °C. Fig. 1 TG/DTG/DTA analysis of BP snake skin

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99 vol% of air [ 2 ]. Carbon aerogels are manufactured by the sol–gel technique by polymerisation and polycondensation [ 2 ], which is followed by drying and pyrolysis of organic matter to nanostructured carbonaceous material. Carbon aerogels

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identify the swelling clay species. A U-RFL-T type UV fluorescence module and a UMNU2 type filter (exciting filter 420–480 nm, emission filter 520 IF, and dichromatic mirror 500 nm) were applied to detect the carbonaceous material in the thin

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Various carbon dust particles

Studies on thermal behaviour

Journal of Thermal Analysis and Calorimetry
Authors: Sonja Eichholz, Martin Lerch, Michael Heck, and Dirk Walter

Nonisothermal analysis of the kinetics of the combustion of carbonaceous materials . J Therm Anal Calorim 80 : 65 – 69 10.1007/s10973-005-0614-9 . 9. Gilot , P , Bonnefoy , F , Marcucuccilli

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Journal of Thermal Analysis and Calorimetry
Authors: Eudes Lorençon, Rodrigo G. Lacerda, Luiz O. Ladeira, Rodrigo R. Resende, André S. Ferlauto, Ulf Schuchardt, and Rochel M. Lago

, 2 ): 1 2 The TEM images show the presence of gold nanoparticles covering the entire surface of the carbonaceous materials. Figure 1a shows an image of MWNT-containing Au nanoparticles with an average diameter of 5.8 nm. In Fig. 1b the

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Journal of Thermal Analysis and Calorimetry
Authors: Marcelo Mendes Viana, Maura Berger Maltez Melchert, Leandro Cardoso de Morais, Pedro Maurício Buchler, and Jo Dweck

[ 12 ]. The solid residue of pyrolysis (coke) contains carbonaceous material as the product of the cracking reactions that take place during thermal treatment in inert atmosphere [ 13 ]. The coke produced can be used as adsorbent material for

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