Explosions equilibrium

Volk, R Bathelt, H. Performance parameters of explosives equilibrium and non-equilibrium reactions. Propellants, Explosives, Pyrotechnics 2002, 27, 136-141. 

F. Volk and H. Bathelt, Performance Parameters of Explosives Equilibrium and Non-Equilibrium Reactions, Propellants, Explosives, Pyrotechnics, V27, 2002. 

Alloys with other useful properties can be obtained by using yttrium as an additive. The metal can be used as a deoxidizer for vanadium and other nonferrous metals. The metal has a low cross section for nuclear capture. 90Y, one of the isotopes of yttrium, exists in equilibrium with its parent 90Sr, a product of nuclear explosions. Yttrium has been considered for use as a nodulizer for producing nodular cast iron, in which the graphite forms compact nodules instead of the usual flakes. Such iron has increased ductility. 

The elution order for neutral species in MEKC depends on the extent to which they partition into the micelles. Hydrophilic neutrals are insoluble in the micelle s hydrophobic inner environment and elute as a single band as they would in CZE. Neutral solutes that are extremely hydrophobic are completely soluble in the micelle, eluting with the micelles as a single band. Those neutral species that exist in a partition equilibrium between the buffer solution and the micelles elute between the completely hydrophilic and completely hydrophobic neutrals. Those neutral species favoring the buffer solution elute before those favoring the micelles. Micellar electrokinetic chromatography has been used to separate a wide variety of samples, including mixtures of pharmaceutical compounds, vitamins, and explosives. 

Dichlorine monoxide is the anhydride of hypochlorous acid the two nonpolar compounds are readily interconvertible in the gas or aqueous phases via the equilibrium CI2 O + H2 0 2H0Cl. Like other chlorine oxides, CI2O has an endothermic heat of formation and is thus thermodynamically unstable with respect to decomposition into chlorine and oxygen. Dichlorine monoxide typifies the chlorine oxides as a highly reactive and explosive compound with strong oxidhing properties. Nevertheless, it can be handled safely with proper precautions. 

CET89, Chemical equilibrium thermodynamics code for evaluating shock parameters in explosive, chemically-reactive systems, NASA 1989. 

N. Y., 3rd edn, 1970]. Acetone was shaken with Drierite (25g/L) for several hours before it was decanted and distd from fresh Drierite (lOg/L) through an efficient column, maintaining atmospheric contact through a Drierite drying tube. The equilibrium water content is about lO M. Anhydrous Mg(C104)2 should not be used as drying agent because of the risk of EXPLOSION with acetone vapour. 

Oxidation Feedstocks generally hydrocarbons Hazard of fire/explosion arises from contact of flammable material with oxygen Reactions highly exothermic equilibrium favours complete reaction... 

If Uvo or more systems are connected together (such as a pipe length with an orifice plate, two or more vessels connected with pipe or duct, or a compartmented vessel) and an explosion develops in No. 1 area, which generally may be at equilibrium pressure with compartments No. 2 and 3 in equilibrium with No. 2, it can cause a pressure rise in front of the dame front in the unburnt gases in the interconnecting spaces (pipe, compartment). The increased pressure in compartment or area No. 1 becomes the starting pressure for an explosion in com-... 

Explosive Density (g/cc) OB (%) Detonation CO moles/mole HE Frozen Equilibrium at 1600°K 1 atm... 

A reaction at steady state is not in equilibrium. Nor is it a closed system, as it is continuously fed by fresh reactants, which keep the entropy lower than it would be at equilibrium. In this case the deviation from equilibrium is described by the rate of entropy increase, dS/dt, also referred to as entropy production. It can be shown that a reaction at steady state possesses a minimum rate of entropy production, and, when perturbed, it will return to this state, which is dictated by the rate at which reactants are fed to the system [R.A. van Santen and J.W. Niemantsverdriet, Chemical Kinetics and Catalysis (1995), Plenum, New York]. Hence, steady states settle for the smallest deviation from equilibrium possible under the given conditions. Steady state reactions in industry satisfy these conditions and are operated in a regime where linear non-equilibrium thermodynamics holds. Nonlinear non-equilibrium thermodynamics, however, represents a regime where explosions and uncontrolled oscillations may arise. Obviously, industry wants to avoid such situations ... 

LEL is the most important of the two limits. It is mostly useful when inflammable substances are handled in confined spaces (reservoirs, painting cabins, ovens etc). Detaiis of limits of inflammability are kept by chemical substance manufacturers who are required to mention them on safety sheets that have to be put at clients disposal. When compared with the equilibrium concentration determined as indicated before, LEL aiiows determination of whether a working environment presents a risk of explosion in the presence of a source of ignition. 

Let us call LEL the lower explosive limit of a given substance in percentage, PI the vapour pressure that allows an equilibrium concentration equal to LEL and Pa the atmospheric pressure... 

The possibilities offered by the lower explosive limit of estimating a flashpoint cc have already been discussed in detail. It would be possible, vice versa, to estimate a lower explosive limit given a flashpoint cc in which there is some confidence. To do so one simply needs to calculate, using equation (1) in paragraph 1.1.2, the vapour pressure of a substance at the temperature of the flashpoint, then for its equilibrium concentration C, in these conditions Ceq = LEL. But an error in has big consequences on Cgq and thus on LEL. This is the reason why this approach is less reliable than the other and can only be used when there Is certainty about the flashpoint. 

Another estimation method of mixture flashpointe was sugg ed by Gmehling (note p.63). The method uses the forecast technique of activity coefficients of iiquid mixtures called UNIFAC that would therefore enable calculation of the vapour pressure of the mixtures and, thanks to Le Chdtelier equation, calculate the temperature to which the mixture has to be heated so that its equilibrium concentration reaches the lower explosive limit. 

These are the basic equations of the hydrodynamic theory of detonation. If p2 and v2 can be determined, they enable the remaining features of the detonation wave to be calculated. Unfortunately p2 and v, relate to conditions in the detonation wave and not to the lower pressure conditions which the explosion products would reach at equilibrium in, for example, a closed vessel. Therefore, further calculations are needed to determine p2 and v2. 

Commercial explosives frequently contain salts, or give other solid residues. In calculations these cause difficulties, as it is not certain whether solid ingredients reach equilibrium with the explosion products. In the calculations it is possible either to assume thermal equilibrium, or to... 

The explosively unstable behaviour of stored nitronium perchlorate is attributed to the formation of small equilibrium concentrations of the isomeric covalent nitryl perchlorate ester (below). 

An unknown event disturbed the equilibrium of the interstellar cloud, and it collapsed. This process may have been caused by shock waves from a supernova explosion, or by a density wave of a spiral arm of the galaxy. The gas molecules and the particles were compressed, and with increasing compression, both temperature and pressure increased. It is possible that the centrifugal forces due to the rotation of the system prevented a spherical contraction. The result was a relatively flat, rotating disc of matter, in the centre of which was the primeval sun. Analogues of the early solar system, i.e., protoplanetary discs, have been identified from the radiation emitted by T Tauri stars (Koerner, 1997). 

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