Large Amounts of Explosives

81 for 3000 kg of ammonia gelatin dynamite. The higher the barricade, the better it inhibits the blast force and flying fragments. The fragments of brick magazine were finer (the radius of the blast was shorter) than those of the concrete magazine 

Detonation, Large-Scale Gap Test. See Ref 42 under Detonation (and Explosion), Experimental Procedures 

Detonation (and Explosion), Lateral Dispersion in. See Detonation (and Explosion), Lateral Expansion (Dispersion), etc 

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Fortunately, for a couple of reasons, the likelihood of a terrorist attack on a nuclear reactor is quite low. Nuclear reactors operate under tight security and incorporate safety systems. In addition, the extensive shielding around reactors would require large amounts of explosives to create a breach. Even if terrorists could transport large amounts of explosives, they would have to breach a security cordon to reach the reactor. Alternatively, they could commandeer a jumbo jet plane to crash into a reactor or a nuclear pond of used cores, but they would have to breach security measures to do so. Computer modeling indicates that the constraction of most reactors would sustain a 300 mph impact from a commercial aircraft, but not aU scientists agree with these findings (1). 

In the evaluation of the explosives by casting cone method, the places of explosion and the packing diameters are exactly the same. The variation of uniconsumption displays the different work capability/ability of explosives. In the same conditions, Ki is for explosive 1 and K2 is for explosive 2. The work ability of two explosives is inversely proportional to their values, A1/A2 = K2IK1. This comparison should be conducted when the two values of n are very close to each other. The repeatability of this method is poor. Packing with relatively large amount of explosives is better. 

Note 2. A very vigorous explosion has occurred in our laboratory in the course of a distillation of a large amount of the propargyl ether, which had been stored for 3 weeks at room temperature. Traces of peroxide (the product had not been kept under nitrogen) might have been responsible for the explosion. In any case it is not advisable to distil large quantities of propargyl ethers at normal pressure. 

Propellants and explosives are chemical compounds or mixtures that rapidly produce large volumes of hot gases when properly initiated. Propellants bum at relatively low rates measured in centimeters per second explosives detonate at rates of kilometers per second. Pyrotechnic materials evolve large amounts of heat but much less gas than propellants and explosives (see Pyrotechnics). 

Criticality Precautions. The presence of a critical mass of Pu ia a container can result ia a fission chain reaction. Lethal amounts of gamma and neutron radiation are emitted, and a large amount of heat is produced. The assembly can simmer near critical or can make repeated critical excursions. The generation of heat results eventually ia an explosion which destroys the assembly. The quantity of Pu required for a critical mass depends on several factors the form and concentration of the Pu, the geometry of the system, the presence of moderators (water, hydrogen-rich compounds such as polyethylene, cadmium, etc), the proximity of neutron reflectors, the presence of nuclear poisons, and the potential iateraction with neighboring fissile systems (188). As Httle as 509 g of Pu(N02)4 solution at a concentration Pu of 33 g/L ia a spherical container, reflected by an infinite amount of water, is a critical mass (189,190). Evaluation of criticaUty controls is available (32,190). 

Anhydrous An anhydrous material does not contain any water molecules. Many substances occur naturally as hydrates, compounds that have a specific number of water molecules attached to them. This water can often be removed by heating and/or vacuum to give the anhydrous material. Anhydrous materials can absorb water from their surroundings and find use as dessicants. Examples include those packets of silica gel you find in some consumer goods, as well as dehumidifying sachets used in clothes closets. When an anhydrous material reacts with water, this could release a large amount of heat, possibly leading to a heat or pressure buildup that could result in an explosion. 

TCDD is the most potent inducer of chloracne. This has been well known since the accident in Seveso, Italy, in 1976 in which large amounts of TCDD were distributed in the environment subsequent to an explosion in a factory that produced a chlorophenoxy herbicide, 2,4,5-T. TCDD is an impurity produced during the production of 2,4,5-T. The most common long-term effect of TCDD exposure was chloracne. Exposed individuals also suffered increased excretion of porphyrins, hyper-pigmentation, central nervous system effects, and liver damage and increased risk of cancer was a long-term consequence of the exposure. In addition to TCDD, polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans, and polychloronaphthalens cause chloracne as well as other effects typical of TCDD. 7i... 

Historically, the outbreak of the first World War provided a stimulus for the industrial preparation of large amounts of synthetic phenol, which was needed as a raw material to manufacture the explosive picric acid (2,4,6-trinitrophenol). Today, more than 2 million tons of phenol is manufactured each year in the United States for use in such products as Bakelite resin and adhesives for binding plywood. 

Explain why there is danger of explosion where a large amount of dry, powdered, combustible material is produced. 

Low temperature. Low-temperature processes (below 0°C) contain large amounts of fluids kept in the liquid state by pressure and/or low temperature. If for any reason it is not possible to keep them under pressure or keep them cold, then the liquids will begin to vaporize. If this happens, impurities in the fluids are liable to precipitate from solution as solids, especially if equipment is allowed to boil dry. Deposited solids may not only be the cause of blockage but also in some cases the cause of explosions. It is necessary, therefore, to ensure that the fluids entering a low-temperature plant are purified. A severe materials-of-construction problem in low-temperature processes is low-temperature embrittlement. Also, in low temperature as in high-temperature operations, the equipment is subject to thermal stresses, especially during start-up and shutdown. 

If the amount of explosive used is too large, the broken rock can be projected for great distances. If the quantity used is too small, the amount of Assuring of the rock can be insufficient to free the explosive gases... 

As Britain is relatively poor in mineral deposits, this type of mining is less important here than in other countries of the world. The gold mines in South Africa, metal mines in the U.S.A., Canada and Sweden all use considerable amounts of explosive. In such mines the methods of working are often appreciably different from those described above and adapted to very large-scale production. 

It should be evident from this discussion that the first explosion limit will be quite sensitive to the nature of the surface of the reaction vessel and its area. If the surface is coated with a material that inhibits the surface chain termination process, the first explosion limit will be lowered. Inert foreign gases can also have the effect of lowering the first explosion limit, since they can hinder diffusion to the surface. If something like spun glass or large amounts of fine wire are inserted, one can effect an increase in the first explosion limit by changing the surface/ volume ratio of the system. 

Tungsten oxide tetrabromide was prepared by condensing a little of the bromide onto the oxide at — 196°C, then allowing slow warming by immersion of the container in an ice bath. Omission of the ice bath or use of large amounts of bromide may lead to explosions. 

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