Detonating secondary

There is little information readily available on lead picrate. However, it is a workable primary explosive. This material is not very powerful and should always be used with a booster charge of an easily detonated secondary explosive. Like all primary explosives, this material is very sensitive to impact, friction, and sparks. 

In nonreactive materials, regions of elevated temperature, or hot spots, have an influence on material strength. In solid explosives this is also true, but the additional effeet is to start exothermal ehemieal reaetions which then lead to detonation. The hot-spot temperatures generated in typical secondary explo-... 

Secondary detonating explosive substance or black powder or article containing a secondary detonating explosive substance, in each case without means of initiation and without a propelling charge, or article containing a primary explosive substance and containing two or more independent safety features D... 

Detonating explosives are primary or secondary. Primary explosives detonate by flame,... 

Uses It can be used as a secondary charge in detonators replacing Tetryl. Mixts with Diaz onitrophenol (Encycl 2, B59) or Tetrazene... 

Some specialized uses of PETN are summarized below. Expendable cartridges for small arms are made by coating unglazed grains or single base smokeless powder with PETN, spraying with plasticized thermoplastic binder and compression molding to the desired shape (Ref 99). Tucker et al (Ref 85) describe a spark detonator without primary expls. Secondary... 

In instances where the expl is to be detonated without a primer and whose output will not reliably initiate secondary HE charges, the initiator takes the form of a stab detonator (Refs 8,12 13), a diagram of which is shown in Fig 4... 

As shown in Fig 4, the stab detonator is a small, sensitive component which is capable of reliably initiating high-order detonation in the next HE element in the expl train. It differs from the primer in that its output will initiate reliably secondary HE charges... 

Temperature field behind the leading shock at different times obtained by the numerical simulations [21]. 1, transverse detonation 2, strong part of the leading shock (overdriven detonation) 3, weak part of the leading shock (inert) 4, induction zone 5, transverse shock 6, unreacted tail 7, primary unreacted pocket and 8, secondary unreacted pockets. (Courtesy of V. Gamezo.)... 

High explosives which detonate to produce shock waves. Materials which are easily detonated by mechanical or electrical stimuli are termed primary explosives . Those requiring an impinging shock wave to initiate them are secondary explosives . 

There are a variety of process safety risks one needs to assess with chemical processes. In general, these risks will lead to an evaluation of the potential for the process to have precipitous changes in temperature and or pressure that lead to secondary events such as detonations, explosions, over pressurizations, fires, and so forth. The most cost-effective way of avoiding these sorts of risks is through the adoption of inherent safety principles. Inherent safety principles are very similar to and complementary to pollution prevention principles, where one attempts to use a hierarchy of approaches to avoid and/or reduce the risk of an adverse event. The reader is referred elsewhere to a more complete treatment of this important area of process design. ... 

The transformations (1) lead to unstable alkyl nitrates, which can detonate very easily. The reactions (2) lead to more or less complete oxidations of the organic molecule. The formation of aldehydes is purely theoretical since they are more oxidisable than alcohols and therefore are not part of the oxidation process by nitric acid. On the other hand, a ketone can form with a secondary alcohol. With tertiary alcohols, carboxylic acid is the only possible outcome of the partial oxidation, which is caused by the breaking of C-C bonds. When the oxidation is out of control, it is likely to have a complete oxidation. Finally, with heavy metal... 

The secondary amine that was used could be tetrahydrocarbazole or pyrol. The reaction was known and not mentioned as being dangerous. The authors of this new experiment used four times the amounts recommended in the method published. They also introduced the ionic compound at 0°C and stopped the cooling rapidly. These changes were sufficient to cause the medium to heat up and then detonate. It was considered to be due to the nitrile polymerisation caused by ammonium salt. 

Detonator. A metal tube containing a primary explosive used for initiating a secondary explosive. 

Secondary explosive. Alternative name for high explosive indicating that the explosive does not burn to detonation but is detonated by suitable devices. 

Various secondary sources of safety data are now listing this as an explosive. I can find no primaiy source for this classification, which seems very improbable. Simple minded use of many computational hazard prediction procedures would show thermodynamically that this compound, like most lower amines, could hypothetically convert to alkane, ammonia and nitrogen with sufficient energy (about 3 kJ/g) to count as an explosion hazard. This reaction is not known to happen. (Simple minded thermodynamicists would rate this book, or computer, and its reader as a severe hazard in an air environment.) Like other bases, iminobispropylamine certainly sensitises many nitro-explosives to detonation. It is used experimentally to study the effect, which may have found technical exploitation and, garbled, could have led to description of the amine as itself an explosive. 

The substantial effect of secondary breakup of droplets on the final droplet size distributions in sprays has been reported by many researchers, particularly for overheated hydrocarbon fuel sprays. 557 A quantitative analysis of the secondary breakup process must deal with the aerodynamic effects caused by the flow around each individual, moving droplet, introducing additional difficulty in theoretical treatment. Aslanov and Shamshev 557 presented an elementary mathematical model of this highly transient phenomenon, formulated on the basis of the theory of hydrodynamic instability on the droplet-gas interface. The model and approach may be used to make estimations of the range of droplet sizes and to calculate droplet breakup in high-speed flows behind shock waves, characteristic of detonation spray processes. 

Primary explosives differ from secondary explosives in that they undergo a rapid transition from burning to detonation and have the ability to transmit the detonation to less sensitive (but more powerful) secondary explosives. Primary explosives have high degrees of sensitivity to initiation through shock, friction, electric spark, or high temperature, and explode whether confined or unconfined. Some widely used primary explosives include lead azide, silver azide, tetrazene, lead styphnate, mercury fulminate, and diazodinitrophenol. Nuclear weapon applications normally limit the use of primary explosives to lead azide and lead styphnate. 

Lead azide (PbN6) is a colorless to white crystalline explosive. It is widely used in detonators because of its high capacity for initiating secondary explosives to detonation. However, since lead azide is not particularly susceptible to initiation by impact, it is not used alone in initiator components. It is used in combination with lead styphnate and aluminum for military detonators, and is used often in a mixture with tetrazene. It is compatible with most explosives and priming mixture ingredients. Contact with copper must be avoided because it leads to formation of extremely sensitive copper azide. 

Secondary explosives (also known as high explosives) are different from primary explosives in that they cannot be detonated readily by heat or shock and are generally more powerful. Secondary explosives can be initiated to detonation only by a shock produced by the explosion of a primary explosive. Widely used secondary explosives include trinitrotoluene (TNT), tetryl, picric acid, nitrocellulose, nitroglycerine, nitroguanidine, cyclotrimethylenetrinitramine (RDX), cyclotetramethylenetetranit-... 

Pentaerythritol tetranitrate (PETN) is a colorless crystalline solid that is very sensitive to initiation by a primary explosive. It is a powerful secondary explosive that has a great shattering effect. It is used in commercial blasting caps, detonation cords, and boosters. PETN is not used in its pure form because it is too sensitive to friction and impact. It is usually mixed with plasticized nitrocellulose or with synthetic rubbers to form PBXs. The most common form of explosive composition containing PETN is Pentolite, a mixture of 20 to 50% PETN and TNT. PETN can be incorporated into gelatinous industrial explosives. The military has in most cases replaced PETN with RDX because RDX is more thermally stable and has a longer shelf life. PETN is insoluble in water, sparingly soluble in alcohol, ether, and benzene, and soluble in acetone and methyl acetate. 

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