Black powder characteristics

Black Powder. Black powder is mainly used as an igniter for nitrocellulose gun propellant, and to some extent in safety blasting fuse, delay fuses, and in firecrackers. Potassium nitrate black powder (74 wt %, 15.6 wt % carbon, 10.4 wt % sulfur) is used for military appHcations. The slower-burning, less cosdy, and more hygroscopic sodium nitrate black powder (71.0 wt %, 16.5 wt % carbon, 12.5 wt % sulfur) is used industrially. The reaction products of black powder are complex (Table 12) and change with the conditions of initia tion, confinement, and density. The reported thermochemical and performance characteristics vary greatly and depend on the source of material, its physical form, and the method of determination. Typical values are Hsted in Table 13. 

Domestic bombings are characteristically accomplished by utilizing improvised low-yield explosives. An example of a low-yield explosive is black powder. 

Although the compositions used in fountains are usually based on black powder propellant, the sparks that are responsible for the fountain effect originate from other substances within the composition. These substances are known as emitters and it is the physical and chemical properties of the emitters that determine the characteristics of the fountain. Various additives are also used to promote the visual effects or to cheapen the composition. 

ToF-SIMS has been utilized to obtain characteristic mass spectra and images from different smokeless gunpowders and black powder samples.17 In the mass spectra obtained, peaks indicative of both the organic and inorganic additive constituents in the gunpowder samples were observed. 

Class A dangerous explosives(detonating or otherwise) of maximum hazard. Their distinguishing characteristic is the susceptibility to deton by a blasting cap. Typical examples are dynamite, PA, TNT, NC, N(i and AN and chlorate expls. Black powder is also included in this group although it cannot be detonated by a commercial blasting cap(ICC Sec 73.53)... 

Tsuchida et al. 213) showed that PVC solutions in tetrahydrofuran dehydrochlorinate when treated with sodium amide in liquid ammonia the product had many of the characteristics of polyacetylene and a conductivity of 10-4 S cm-1 but was an infusible black powder. It was found that reaction of PVC powder gave only limited dehydrochlorination of the surface. 

A terpene inhibitor is usually added to the monomer to prevent spontaneous polymerisation, and in its absence, the monomer will spontaneously explode at pressures above 2.7 bar. The inhibited monomer will explode if ignited [1], Explosion under thermal initiation is now held to be a disproportionation, that to tetrafluoromethane and carbon gives 3.2 kJ/g, the same energy as black powder [3]. Liquid tetrafluoroethylene, being collected in a liquid nitrogen-cooled trap open to air, formed a peroxidic polymer which exploded [2], Tetrafluoroethene is stabilised for transport or storage by admixture with considerable proportions of hexafluoropropene [4]. Explosion characteristics in long pipes at 23 bar pressure have been studied [5]. 

Melanin, which is prepared by polymerization with a macromolecule-metal complex, is isolated as a black powder and shows strong absorption in the ultraviolet and visible regions. The free radical species is stable against heat, acid, and base, and the EPR shows a singlet signal at g = 2.00. These properties are also important in the physiological characteristics of melanin. 

Explosive Actuator XE-16A was developed at NAVORD Labs to replace the Mk 1 Mod 0 actuator for use in Mk 52 drill mine. Better surveillance characteristics were obtd by using Unique Powder (a smokeless proplnt of unspecified compn)as a substitute for Black Powder formerly used as the base chge. Milled normal Pb Styphnate was substituted for DDNP-Potassium Chlorate mix as die ignition chge. Several design- changes to increase ruggedness were also made. Laboratory field tests indicated that the XE-16A Actuator would be a satisfactory actuator in the Mk 52 Drill Mine Ref E.E. Kilmer M.J. Falbo, NAVORD Rept 6111(1958)... 

Pine charcoal burns in combination with ammonium perchlorate at F/O = 2 10 producing a yellow flame, but no sparks or fire dust. A mixture of pine charcoal, sulphur and potassium nitrate in the weight ratio 30 10 60 burns producing pretty. orange red fire dust. This characteristic is generally seen with other charcoals but pine charcoal produces the most pretty fire dust of all. On the other hand, the phenomenon shows that pine charcoal does not complete the reaction and produces less gas in black powder-type compositions. Therefore pine charcoal is used to produce fire dust and not to obtain force. 

One of the characteristics of black powder is that it is a fast burning mixture. 

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