Calorimetry is one of the main techniques of thermal analysis. Most of physical or chemical modifications of material are associated with thermal effects whereby heat is absorbed (i.e., melting) or released (i.e., thermal decomposition). Typically, calorimetric experiments are performed with Differential Scanning Calorimetry (DSC), which measures the heat flux absorbed or released by the sample following the same temperature program as a reference material. In these experiments, measurements are typically carried out on a few milligrams of sample. However, for many applications one has to handle nanograms or even picograms of sample. One of such applications is relevant to studies of materials which can release a significant amount of energy during their decomposition (energetic materials). Calorimetry able to handle nanograms of sample could find potential applications in the field of explosives detection. Nanocalorimetry allows to heat small amounts of sample (a few nanograms to a few hundred picograms) at extreme heating rates, i.e. up to one million °C/s. The temperature increase can initiate several phenomena in energetic materials, therefore the calorimetry could be an appropriate technique to characterize and to detect energetic materials. The energetic materials used in this study are nitrocellulose (NC), hexogen (RDX), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-ltexaazaisowurtzitane (CL-20) and penthrite (PETN). The manuscript presents our results on the nanocalorimeter calibration, on the thermal behaviour of the explosives studied with nanocalorimetry and also includes an evaluation of nanocalorimetry as a tool for explosives detection.
| Identifer | oai:union.ndltd.org:CCSD/oai:tel.archives-ouvertes.fr:tel-00702242 |
| Date | 19 November 2010 |
| Creators | Piazzon, Nelly |
| Publisher | Université de Haute Alsace - Mulhouse |
| Source Sets | CCSD theses-EN-ligne, France |
| Language | English |
| Detected Language | English |
| Type | PhD thesis |
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