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usually used as fuels to enhance the energy characteristics and improve the ignition property of pyrotechnics [ 6 , 7 ]. The combination of KClO 4 and Mg are typically used for flare pyrotechnics and fireworks [ 8 , 9 ]. For some of these applications

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Journal of Thermal Analysis and Calorimetry
Authors: Dumitru Oancea, Valentin Munteanu, Domnina Razus, and Maria Mitu

Introduction The ignition and subsequent combustion of a fuel/air mixture by hot solid surfaces, either inert or catalytic, is a subject of great interest from both practical and theoretical points of view [ 1 ]. Several

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is in the initiation phase during the whole phase of pre-flashover. Therefore, determination and comparison of the substantial initiation parameters (ignition and flash ignition temperature, ignition and flash ignition induction period and critical

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under control, considerable attention has been focused on the problems such as ignition, combustion rate and burnout. In recent years, much research [ 1 – 3 ] has been carried out on the catalytic combustion of coal in order to improve combustion

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The “Ignition” criteria taken from the theory of combustion are suggested for the determination of various kinetic characteristics with the thermophysical parameters depending upon the temperature.

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The effects of the experimental conditions (sample size, heating rate, static and dynamic atmosphere) were studied on the value of the flash-ignition temperature (T i) obtained with a modified derivatograph able to measureT i simultaneously with the TG, DTG, DTA and T curves. The effects of various parameters are discussed and the optimum conditions determined.T i for bleached cotton fibre was found to be 270±1 °C.

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The thermal ignition behaviour of various mixtures of organic fuels, magnesium and ammonium nitrate (AN) has been examined by differential thermal analysis technique. It has been observed that the thermal decomposition/ignition of organic fuel-AN mixtures is modified significantly in the presence of magnesium metal. The decomposition characteristics of the binary mixtures of AN with various metals indicate the specific action of magnesium and zinc in lowering the decomposition temperature. A possible explanation for the low temperature decomposition is given in terms of the solid state reaction causing the fusion of AN which further reacts with the metal resulting in a highly exothermic reaction.

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Abstract  

During the past several years, a significant effort has been on investigation of reaction front propagation and the rate of energy release in heterogeneous systems consisting of nanopowder reactants. Substantial size reduction of each reactant powder (e.g. from micro- to nano-size) leads to increase of reaction front propagation in some systems under unconfined conditions by approximately two to three order of magnitude. This paper presents key challenges associated with processing and use of nanothermite materials and characterization of nanoreactants. Reaction constants, such as activation energies and frequency factors were determined using DSC technique for several nanothermite systems based on nanosize aluminum and iron oxide, bismuth trioxide, and molybdenum trioxide. Experimental data of ignition delay times for different nanothermite systems using laser energy source were compared well to those predicted by proposed mathematical model.

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Abstract  

Activation energies of ignition for the thermokinetic oscillations obtained during the heterogeneous catalytic oxidation of ethanol on Pd/Al2O3 in a dynamic calorimeter were obtained using the minimum values of the temperature oscillations. These activation energies of ignition are greater than the activation energies of the corresponding oscillations. The obtained results are discussed by assuming a PdOx redox cycle.

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A series of pyrrhotites of various stoichiometries was synthesized and characterized, and fractionated into four particle size ranges. The ignition temperatures and extent of reaction were determined by a thermogravimetric method. These measurements enabled the effect of stoichiometry and particle size on the ignition temperature and extent of oxidation to be established. The trends observed in the ignition behaviour are consistent with the concept of sulfur evolution being the key to the initiation of the ignition reaction.

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