Pyrotechnics density

A recent review relating the pyrotechnic reaction mechanism, particle size, stoichiometry, temp and compaction density to burning rate is Ref 66, and a study of the effect of multidimensional heat transfer on the rate of flame propagation is Ref 120, which showed that the material of the delay body has no effect on the performance of most delay compns, a finding which agrees with test data... 

Klapotke, T. M., and Ang, H.-G., Estimation of the Crystalline Density of Ni-tramine (N-N02-based) High Energy Density Materials (HEDM), Propellants, Explosives, Pyrotechnics, Vol. 26, 2001, pp. 221-224. 

It has been suggested that the explanation of pulmonary disease among powder workers in other countries may lie in the duration of exposure, the size of the particles, the density of the dust, and especially the fact that all reported cases have been associated with exposure to a submicron-sized aluminum pyrotechnic flake (powder), which has been lubricated with a nonpolar aliphatic oil rather than the usually employed stearic acid 7... 

Oxley, J. C., J. L. Smith, J. Moran, and K. Shinde. Determination of the vapor density of triacetone triperoxide (TATP) using a gas chromatography headspace technique. Propellants, Explosives, Pyrotechnics, 30(2), 127-130 (2005). 

A new area of research and activity in recent years is the development of new explosives based on furazans, furoxans and tetrazines in order to achieve an increase in density, stability, insensitivity and velocity of detonation. As a result, a number of prospective HEMs which are potential ingredients of explosive, propellant and pyrotechnic formulations have been synthesized. 

Chavez and Hiskey continued their research on 1,2,4,5-tetrazine-based explosives and synthesized a number of derivatives which are considered interesting as propellant or smoke-free pyrotechnic ingredients because of their low carbon content, high heat of formation and a density of-1.61 g cm4. One such compound is 3,6-dihydrazino-l,2,4,5-tetrazine which appears to be an important energetic fuel [275, 276]. 

Some of the important properties which are considered when choosing the ingredients for pyrotechnic formulations are density, hygroscopicity, melting and boiling points and decomposition temperatures, oxygen content of oxidizers, thermal conductivity of fuels and containers, nature of combustion products and toxicity etc. 

U is a member of the actinide series of elements which, together with the rare earths and the transition elements, possess a high heat of oxidation, a low oxide density compared with that of the metal, and the presence of an unfilled d shell in its electronic structure. While the reasons for the high pyrophoric potential of U are not clearly understood, they are thought to be related to these aforementioned properties (see under Pyrotechnics in Vol 8, P511 and Pyrophoric Incendiary Agents , P503-L)... 

Shidlovskii(Ref 15) discusses the theory of burning pyro compns and gives formula for detg their rates of burning. He lists the linear rates of burning in mm/sec for the following stoichiometric binary pyrotechnic compns when compressed to densities 0.7-0.9 S+ KClOs 2, S+ Ba(C103)j, 2, charcoal KCIO-6. charcoal BafClO.). 2.S. 

D Cast Density. It is the density of a material in the solidified state. See also item E Ew Charge (or Loading) Density (Densite de charganent in Fr). This term is applied to densities of expls, proplnts or pyrotechnics loaded... 

Lu Packed Density. Accdg to MIL-STD-1233, Method 400, the packed d of a powdered material is the weight per unit volume of material which has been packed until it has attained the most compact form. Packed d indicates the loading d of loose pyrotechnic powders (See also item E) Relative Density (d ). It is the ratio of the absolute d at t°C to abs d of water at 3.98°C (0.999973 g/cu cm, its maximum d) and is expressed as g/ml. It is also called "density (or specific graviry) relative to water at 4°C ... 

Lv Packed Density. Accdg to MIL-STD-I233, Method 400, the packed d of a powdered material is the weight per unit volume of material which has been packed until it has attained the most compact form. Packed d indicates the loading d of loose pyrotechnic powders (See also item E)... 

The further new nitroethyl compounds based on boron esters are tris-(2-nitro-ethyl) borate and tris-(2,2,2-trinitroethyl) borate. Especially the trinitroethyl derivative is a suitable candidate for high energy density oxidizers and for smoke-free, green coloring agents in pyrotechnic compositions. Tris-(2-nitroethyl) borate and tris-(2,2,2-trinitroethyl) borate can be obtained from boron oxide with 2-nitroetha-nol and 2,2,2-trinitroethanol, respectively ... 

While Region II can be compared with the hot-wire initiation of primary explosives or pyrotechnic compositions, the laser power densities in region IV also make it possible to directly shock initiate secondary explosives by laser irradiation. The laser power densities of Region IV are achieved by solid-state lasers with laser powers of at least 100 W. In contrast, laser diodes ( 1-10 W) only provide power densities which fall into the regions II and III. However, more powerful laser diodes have been gradually developed and therefore, laser diode initiators (LDI) have be-... 

In both explosives and propellants the materials are relatively non-porous. The binders and plasticizers used effectively fill the pore spaces. Pyrotechnics are porous and the heat transfer related to the hot gas permeation into the reactant material mixture becomes important. In many pyrotechnics no binders or plasticizers are used. The explosives and propellants have burning (or detonation) rates that depend on density, temperature, and pressure. However, the burning rates of pyrotechnics are, in addition, affected by porosity, particle sizes, purity, homogeneity (degree of mixing), and stoichiometry (fuel or oxidizer ratio). 

Eremenko, L. E., Interrelationship between Density and Structure in an Explosive, in Proceedings of the 11th Symposium on Explosives and Pyrotechnics, Philadelphia, Peruisylvania, 1981. 

Eremenko, L. T., Density Calculation of Aromatic Crystals Using Their Structure, in Proceedings of the 8th International Pyrotechnics Symposium, Colorado, 1982. 

Cooper, P. W., Extending Estimation of C-J Pressure of Explosives to the Very Low Density Region, Proceedings of 18th Interational Pyrotechnic Symposium, Breckenridge, Colorado, July 1992. 

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