Decomposition reactions mixed explosive

Explosion prevention can be practiced by mixing decomposable gases with inert diluents. For example, acetylene can oe made nonexplosive at a pressure of 100 atm (10.1 MPa) by including 14.5 percent water vapor and 8 percent butane (Bodurtha, 1980). One way to prevent the decomposition reaction of ethylene oxide vapor is to use methane gas to blanket the ethylene oxide hquid. 

Most explosive and propellant compositions contain a mixture of components so as to optimize their performance. Some of the components may not contribute to the heat liberated and may not even contain oxygen. These materials may however, contribute to the gaseous products and reduce the actual temperatures obtained on detonation of the explosive or burning of the propellant. An example of a typical mixed explosive composition is one which contains 60% RDX and 40% TNT, and where the heat of explosion Q has been optimized. In order to calculate the values of Q and V for this composition the oxygen balance and the reaction for decomposition need to be determined. But even before these can be calculated the atomic composition of the mixture must first be established. 

The reaction for the decomposition products of the mixed explosive composition can be determined by applying the modified Kistia-kowsky Wilson rules as shown in Table 5.16. 

Apart from the reaction of the decomposition of nitrate esters some other changes can occur in mixed explosives, such as the reaction of the oxidation of aluminium, particularly marked in watcr-gel explosives. Also permitted (permissible) explosives containing ion exchange mixtures of sodium nitrate witli ammonium chloride a double exchange reaction can occur ... 

Explosion - an abrupt oxidation, or decomposition reaction, that produces an increase in temperature, or pressure, or in both temperature and pressure simultaneously. Explosive atmosphere - flammable substances in the form of gases, vapours, mists or dusts mixed with air under atmospheric conditions, which, after ignition has occurred, combustion spreads to the entire unburned mixture. 

Quite complex kinetic behavior has been identified on some surfaces. For instance, on Ir(100), the TPD data from NO-saturated surfaces display two N2 desorption peaks, one at 346 K from the decomposition of bridge-bonded NO, and a second at 475 K from the decomposition of atop-bonded NO molecules [13], Interestingly, the first feature is quite narrow, indicating an autocatalytic process for which the parallel formation of N20 appears to be the crucial step. An additional complication arises from the fact that this Ir(100) surface undergoes a (1x5) reconstruction, and that NO adsorbed on the metastable unreconstructed (lxl) phase leads to N2 desorption at lower temperatures. In another example, on the reconstructed hexagonal Pt(100) surface, when a mixed NO + CO adsorbed layer is heated, a so-called surface explosion is observed where the reaction products (N2, C02 and N20) desorb simultaneously in the form of sharp peaks with half-widths of only 7 to 20 K. The shape of the TPD spectra suggests again an autocatalytic mechanism [14],... 

Materials that in themselves are capable of detonation or explosive decomposition or explosive reaction, but require a strong initiating source or must be heated under confinement before initiation Materials that are sensitive to thermal or mechanical shock at elevated temperatures and pressures Materials that react explosively with water without heat or confinement heat of mixing greater than 600 cal/g Less than 1,000 but greater than 100 W/mL... 

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