Explosives chemical constitution

Explosives and Dangerous Chemicals Constitutional Aspects of Search AND Seizure... 

Some fats, oils and waxes have been used as ingredients in explosive compositions, such as plastic explosives. They can also be nitrated to give nitro- or nitrate compounds Refs 1) T.P. Hiditch, "The Chemical Constitution of Natural Fats , Chapman Hall,... 

Chemical constitution The fact that some common chemical compounds which contain groups like nitro (-N02), nitrate (-0N02) and azide (-N3) etc. undergo explosion when heated means that these are intrinsically in a condition of internal strain and on heating, this strain increases leading to a sudden disruption of molecules and consequent explosion. In some explosives, this condition of molecular instability is so high that decomposition takes place at ordinary temperatures. 

The VOD of an organic explosive is also a function of the energy produced by its decomposition and therefore, a relationship has been derived between detonation properties of an explosive and its chemical constitution. Similarly to Bernard [69, 70], Rothstein and Peterson [71] also postulated for a gamut of an ideal , H, N, type explosive, a simple empirical linear relationship (Equation 1.11) between VOD at theoretical maximum density (TMD) and a factor, F, which solely depends upon chemical constitution and structure. 

A detailed account of the compatibility and stability of explosives-definition, implications and effect of various parameters such as temperature of storage, chemical constitution of explosive vis-a-vis other ingredients, sunlight and electrostatic discharge etc has already been given in Chapter 1 (Section 1.4.1). In this section, the test methods used to determine compatibility and stability are discussed. 

Due to the fact that mixing of the fuel and air is carried out in advance, the rate of reaction in a gaseous mixture is basically determined by thermal factors and by the kinetics of the chemical reaction. It is precisely the clarification of the role and laws of chemical reaction in a flame and in an explosion that constitutes our task. 

These activation energies resemble those found by Thomas and Tompkins (Ref 27) for the photolytic decompn of similar materials, and Kaufman suggested similar behavior despite the varied chemical constitution represented. The data in Table 8 also indicates that large gas evolution is not entirely related to a decrease in explosiveness. It can be seen that while DDNP and MF gassed excessively and showed reduced ability to crush sand after irradiation, dex-trinated Pb azide and RDX also evolved a large amount of gas but did not show impairment of sand values (actually MF could only be initiated with Pb azide in the sand test after a gamma dose of 2.97 x 107 R with a BlkPdr fuze it would only bum). The last generalization made was that the lower limit at which decompn could be detected was about 106 R... 

Solid state physical structure appears to be as significant as chemical constitution in dete. mining the stability of explosives, but apart from crystal structure determination on lower molecular weiglit compounds, such as diaminutriniiro-benzene (9) there is little information available on the magnitude of molecular interactions or crystal lattice effects in these remarkable explosives. 

Other parameters are humidity of the material and, not least, the chemical constitution. Furthermore, dust explosions require a much higher ignition energy than va-pour/air mixtures to trigger the event. 

Upper Explosive Limit Also known as Upper Flammable Limit. Is the highest concentration (expressed in percent of vapor or gas in the air by volume) of a substance that will burn or explode when an ignition source is present. Theoretically above this limit the mixture is said to be too rich to support combustion. The difference between the LEL and the UEL constitutes the flammable range or explosive range of a substance. That is, if the LEL is one ppm and the UEL is five ppm, then the explosive range of the chemical is one ppm to Five ppm. (See also LEL)... 

Ammonia or its salts are employed in a variety of ways in many trades. From it nitric acid, the vital necessity for the manufacture of all high explosives, can be made it is an essential for the Brunner Mond or Solvay ammonia soda process for the production of alkali in the liquid form it is employed all over the world in refrigerating machinery, but its enormous and increasing use is in agfriculture, where, in the form of sulphate of ammonia, it constitutes one of, if not the most important chemical manures known to man. During the year 1916 350,000 tons of ammonium sulphate were produced in this country, the larger proportion of which was consumed in agriculture—a proportion likely to increase and not diminish if the demand for home production of food continues. 

Reactive chemicals are those that tend to undergo rapid or violent reactions under certain conditions. Such substances include those that react violently or form potentially explosive mixtures with water, such as some of the common oxidizing agents (Table 1.6). Explosives (Sudweeks et al., 1983 Austin, 1984) constitute another class of reactive chemicals. For regulatory purposes, those substances are also classified as reactive that react with water, acid, or base to produce toxic fumes, particularly hydrogen sulfide or hydrogen cyanide. 

This chapter will focus on (1) basic principles of search and seizure law (2) the balance between law enforcement s use of science and technological advances to the Fourth Amendment (3) when exploitation of technology should be governed by the Fourth Amendment constraints of unreasonable searches as it pertains to explosives and dangerous chemicals and (4) effect of the USA Patriot Act and related legislation on the Fourth Amendment. The question of what constitutionally determines a reasonable search is simple, its answer and application are not. 

There are two paradigms of legal viewpoints for the detection of explosives and illicit chemicals based upon the Fourth Amendment. The traditional constitutional search and seizure aspects of the law, and second, the informal transitional perspectives predicated upon its manipulation for national security... 

Wm H- Rinkenbach, EXPLOSIVES Their. Materials, Constitution and Analysis , Bull 219(1923), ppll6—118(Physical examination of Blasting Explosives) 118—19 (Dope-size test) 119—43 (Chemical Analysis of Blasting Explosives) 5) C.E. Munroe J.E. Tiffany, Physical Testing of Explosives at the Bureau of Mines Experimental Station, Bruceton, Pennsylvania , USBurMines Bull 346(1931)... 

Some of the reactions described in this chapter constitute what is virtually a separate and distinct type of chemical change, namely one where there is no region of transition between very slow reaction and explosively rapid reaction. Such changes, which must be exothermic, depend upon branching reaction chains which get out of hand when a certain critical concentration is exceeded. 

Cotton "lint , the substance from which cloth is made, is too expensive for use in the explosive industry. It has also been found that these long fibres are much more difficult to nitrate than the shorter and less expensive "linters . Hence the purified "linters constitute the principle source of cellulose for the manufacture of nitrocellulose explosives and plastics (See also under Cotton, Chemical ... 

Risks linked with chemical processes are diverse. As already discussed, product risks include toxicity, flammability, explosion, corrosion, etc. but also include additional risks due to chemical reactivity. A process often uses conditions (temperature, pressure) that by themselves may present a risk and may lead to deviations that can generate critical effects. The plant equipment, including its control equipment, may also fail. Finally, since fine chemical processes are work-intensive, they may be subject to human error. All of these elements, that is, chemistry, energy, equipment, and operators and their interactions, constitute what we call process safety. 

First, a waste (or any other material) may be hazardous due to its physical and chemical properties, rather than the presence of hazardous substances. For example, a material that is readily explosive or reactive (e.g., hydrogen gas, liquid sodium metal) clearly constitutes a hazard even though the constituent substances themselves may not be hazardous to human health. EPA has identified wastes as hazardous if they are ignitable, corrosive, or reactive. 

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