Oxidizer-rich material

Table 9.3 shows the measured detonation velocities and densities of various types of energetic explosive materials based on the data in Refs. [9-11]. The detonation velocity at the CJ point is computed by means of Eq. (9.7). The detonation velocity increases with increasing density, as does the heat of explosion. Ammonium ni-trate(AN) is an oxidizer-rich material and its adiabatic flame temperature is low compared with that of other materials. Thus, the detonation velocity is low and hence the detonation pressure at the CJ point is low compared with that of other energetic materials. However, when AN particles are mixed with a fuel component, the detonation velocity increases. On the other hand, when HMX or RDX is mixed with a fuel component, the detonation velocity decreases because HMX and RDX are stoichiometrically balanced materials and the incorporation of fuel components decreases their adiabatic flame temperatures. 

Although gravimetric methods have been used traditionally for the determination of large amounts of tellurium, more accurate and convenient volumetric methods are favored. The oxidation of teUurium(IV) by ceric sulfate in hot sulfuric acid solution in the presence of chromic ion as catalyst affords a convenient volumetric method for the determination of tellurium (32). Selenium(IV) does not interfere if the sulfuric acid is less than 2 N in concentration. Excess ceric sulfate is added, the excess being titrated with ferrous ammonium sulfate using o-phenanthroline ferrous—sulfate as indicator. The ceric sulfate method is best appHed in tellurium-rich materials such as refined tellurium or tellurium compounds. 

The literature on the oxidation of nickel-copper alloys is not extensive and emphasis tends to be placed on the copper-rich materials. The nickel-rich alloys oxidise according to a parabolic law and at a rate similar to that for nickel Corronil (Ni-30Cu) exhibited a parabolic rate behaviour below 850°C but a more complex behaviour involving two parabolic stages above 900°C. Electron diffraction examination of the oxide films formed on a range of nickel-copper alloys showed the structures of the films to be the same as for the bulk oxides of the component metals and on all the alloys examined only copper oxide was formed below 500°C and only nickel oxide above 700°C . 

It has been reported that the value of the cubic lattice parameter, which is directly related to the average oxidation state of the manganese, is critical to obtain effective cycling. The lattice parameter should preferably be 8.23A or less, and such values are associated with lithium-rich materials, Lii+Mriz-jOi, where the average manganese oxidation state is 3.58 or higher this value minimizes dissolution of manganese and also the impact of the... 

Polymeric materials are used as binders to hold sohd particles together so as to formulate composite explosives or composite propellants. The polymeric materials also constitute part of the fuel ingredients when the crystalline particles are oxidizer-rich. Various types of hydrocarbon polymers are used as polymeric binders. 

Since nitramine pyrolants are fuel-rich materials, the flame temperature decreases with increasing hydrocarbon polymer content The polymers act as coolants and generate thermally decomposed fragments as a result of the exothermic heat of the nitramine particles. The major decomposition products of the polymers are H2, HCHO, CH4, and When AP particles are incorporated into nitramine pyrolants, AP-nitramine composite pyrolants are formed. AP particles produce excess oxidizer fragments that oxidize the fuel fragments of the polymers that surround them. Thus, the addition of AP particles to nitramine pyrolants forms stoichiometricaUy balanced products and the combustion temperature increases. 

A number of clays are layered silicate-like materials. Most clays contain finely divided quartz, micas, and feldspars. Iron oxide-rich clays are employed to make pottery and terracotta articles. Clays containing iron oxide and sand are used to make bricks and tiles. Clays rich in calcium and magnesium carbonate are known as marls and are used in the cement industry (Section 12.2). 

The oxidation of olefins can result in the formation of organic hydroperoxides. These compounds readily decompose to form alcohols, carbonyl compounds, and other oxidized species. These oxidized hydrocarbons can further react to form highly cross-linked, oxygen-rich materials. Some of these species can adhere to metal surfaces to form a hard vamishlike film or coating on metal parts. This varnish can act as a site for further deposition and eventual corrosion of metal. In severe cases, varnish can interfere with the hydrodynamic lubrication of moving metal parts and efficiency of component operation. 

Hybrid Rocket Propellants. A special proplnt combination of unlike materials, particularly of unlike physical characteristics. Typical hybrid proplnt combinations are a solid fuel (or oxidizer) in combination with a liquid oxidizer (or fuel) in tjiat order. Sometimes a grain of solid fuel is encased in the combustion chamber of a rocket engine and burned in combination with liq oxygen. Similarly, a liq fuel may be injected into a combustion chamber in contact with a solid oxidizer. Another example is the use of concentrated hydrogen peroxide and a hydrocarbon fuel. In this case, the hydrogen peroxide is converted by decompn into a hot gas contg oxygen. The fuel is injected downstream of the first reaction, mixed with the hot oxidizer-rich gas, and burns (Ref 1)... 

The dielectric relaxation of bulk mixtures of poly(2jS-di-methylphenylene oxide) and atactic polystyrene has been measured as a function of sample composition, frequency, and temperature. The results are compared with earlier dynamic mechanical and (differential scanning) calorimetric studies of the same samples. It is concluded that the polymers are miscible but probably not at a segmental level. A detailed analysis suggests that the particular samples investigated may be considered in terms of a continuous phase-dispersed phase concept, in which the former is a PS-rich and the latter a PPO-rich material, except for the sample containing 75% PPO-25% PS in which the converse is postulated. 

The effect of amending soil with other types of organic-rich material has also been investigated by sequential extraction. These materials include chicken manure and cowpea leaves (Li et al, 1997) spent mushroom compost, commercial humic acid and poultry litter (Shuman, 1998) and cow manure, pig manure and peat soil (Narwal and Singh, 1998). The mechanisms by which inorganic additives (zeolite, apatite and iron oxide) reduce uptake of Cd and Pb by crops have also been studied (Chlopecka and Adriano, 1997). 

Pyrolysis can be performed for many different reactors. The prodnct distribntion varies markedly between the different reactor types and the reaction conditions, snch as temper-atnre, bed materials or catalyst. The aim of the pyrolysis is the redaction of wastes for landfilling and the prodnction of fnels. Especially fuel oil with a high calorific value is an interesting product. Char can be used as a fuel, but is also seen as a precursor for other carboneous materials such as activated carbon. The best way to obtain these products is decarboxylation of the polymer. In this way carbon oxide-rich gas is produced. 

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