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An electric voltage pulse with amplitude of up to 0.6 V is generated during the reaction between nickel and aluminum powders by a high temperature moving reaction front. The electrical signal formed during the initial stages of the combustion is annihilated before the moving front attained its maximum temperature.

A short temporal electrical impulse is generated during the nitridation of mixtures of titanium and titanium nitride by a high temperature moving reaction front. The generation of an electric field during a rapid high-temperature nitridation is most probably due to the different diffusion velocities of charge carriers through the growing titanium nitride shell during the initial stage of the reaction.

The evolution and dynamics of hot zones on the top of a shallow packed-bed reactor, packed with spherical catalyst pellets (Pd/Al2O3) is studied using infrared thermography. The experiments suggested that global coupling between the top of the bed and the unconverted reactants stabilize the spatiotemporal patterns, which may not exist in its absence.

Chemomagnetic field detection using solid state combustion and liquid-solid reactions, is described.

Cobalt ferrite Co[Fe.sub.2][O.sub.4] crystalline nanoparticles (50-100 nm) were produced by carbon combustion synthesis of oxides (CCSO). In this combustion synthesis process, the exothermic oxidation of carbon generates a thermal reaction wave that propagates through the solid reactants mixture of CoO and [Fe.sub.2][O.sub.3] converting it to cobalt ferrite. The extensive emission of C[O.sub.2] increased the porosity and friability of the product. The quenching front method combined with XRD and VSM characterization revealed that crystalline Co[Fe.sub.2][O.sub.4] particles formed in the early stage of the combustion, before the temperature reached its maximum. The maximum value of the coercivity of the quenched product within the front region was 940 Oe with a magnetization of 15 emu/g. The as-synthesized ferrites had hard magnetic properties with coercivity of 700 Oe and saturation magnetization of up to 47 emu/g. Index Terms--Carbon combustion, cobalt ferrites, nanostructured materials.