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چکیده
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The lactose/KClO3 is a widely used pyrotechnic mixture to vaporize organic materials, such as smoke dyes. However, because of low ignition temperature of this mixture, serious precaution should be taken into account to prevent its accidental self-ignition. In order to find a safe and efficient alternative of this conventional mixture, KClO3 has been replaced by common oxidizing agents including KMnO4 ,KNO3 , KClO4 , Ba(NO3 ) 2 , PbO2 and NH4ClO4 . TG and DTA analysis have been used to obtain thermal characteristic of the mixtures. Based on ignition temperature of the pyrotechnic mixtures we can divide them into four categories as follows: (1) the mixture igniting at low temperature, i.e., at about 200 °C. (2) Moderate tem- perature igniting mixture, in which ignition occurs at 300–400 °C. (3) High temperature igniting mixture with ignition temperature higher than 400 °C .(4) Not igniting # mixtures. Also, the apparent activation energy ( E ), DG , # # DH , DS and critical ignition temperature ( Tb ) of the ignition processes of low and moderate temperature igniting mixtures were obtained from the DSC experiments. Finally, among the investigated mixtures, lactose/KNO3 can be considered as a safe and efficient pyrotechnic composition for vaporization of organic materials, such as smoke dyes, due to its moderate safe ignition temperature.
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