Shock-condensation processes

On a different note, after some 50 years of intensive research on high-pressure shock compression, there are still many outstanding problems that cannot be solved. For example, it is not possible to predict ab initio the time scales of the shock-transition process or the thermophysical and mechanical properties of condensed media under shock compression. For the most part, these properties must presently be evaluated experimentally for incorporation into semiempirical theories. To realize the potential of truly predictive capabilities, it will be necessary to develop first-principles theories that have robust predictive capability. This will require critical examination of the fundamental postulates and assumptions used to interpret shock-compression processes. For example, it is usually assumed that a steady state is achieved immediately after the shock-transition process. However, due to the fact that... 

Several variations on the conventional pre-cure process have been explored, including short one-step flash-dry-curing (shock condensation) of cellulosic fabrics with the risk of crosslinker migration during the quick drying. The... 

D.C. Wallace, Computer Simulation of Non-Equilibrium Processes, in Shock Waves in Condensed Matter (edited by Y.M. Gupta), Plenum, New York, 1986, pp. 37-49. 

R.A. Graham, Shock Compression of Solids as a Physical-Chemical-Mechanical Process, in Shock-Waves in Condensed Matter—1987 (edited by S.C. Schmidt and N.C. Holmes), Elsevier Science, Amsterdam, 1988, pp. 11-18. 

The book includes among other topics Definition of expln and classification of expln processes, pp 9-l6 Theory of shock waves, which includes "shock adiabat on p 190 (pp 182-224) Theory of deton waves (pp 225-27) Hugoniot curve for detonation waves (p 228) Hydrodynamic Theory of deton (p 226) Explosion in air. (pp 555-663) Theory of point initiation of deton, called in Rus "Teoriya tochechnago vzryva (pp 598-624) Theory of spherical expln (pp 624-40) Explosion in condensed medium (pp 664-81) Propagation of shock waves in water (pp 681-90) Some problems of theory of deton in liquids (pp 690-98) Propagation of waves in solids (pp 708-18) and Theory of deton in earth. (pp 718-44)... 

In condensed phase materials, a differentiation between deflagration or detonation is vaporization by endothermic or exothermic processes. If exothermic reaction is initiated within the volume occupied by condensed materials, constant pressure processes are precluded. It has been shown that, by carefully avoiding shock initiation, the most powerful high explosives may be burned in a deflagrating manner (K3). 

Turning to the detonation of condensed EM we note that in this case the study of the equation of state of a dense gas in which repulsion of molecules is more important than their thermal motion turned out to be non-trivial (see the fundamental work by L. D. Landau and K. P. Stanyukovich).29 Water-filled EM were studied by Yu. B. Khariton.30 At present A. N. Dremin is developing ideas on the specific influence of a shock wave on the kinetics of reaction in an EM.31 For gas-dispersion systems the structure of detonation waves has become the subject of numerous studies related to explosions of coal dust husks in grain elevators, gas suspensions of dust in wood processing, etc.32,33 34 5 Works on gas suspensions have also been published abroad.36,37 In gas suspensions we may expect that the reaction rate is determined by diffusion and depends weakly on the temperature. 

C60 has not yet been detected in primitive meteorites, a finding that could demonstrate its existence in the early solar nebular or as a component of presolar dust. However, other allotropes of carbon, diamond and graphite, have been isolated from numerous chondritic samples. Studies of the isotopic composition and trace element content and these forms of carbon suggest that they condensed in circumstellar environments. Diamond may also have been produced in the early solar nebula and meteorite parent bodies by both low-temperature-low-pressure processes and shock events. Evidence for the occurrence of another carbon allotrope, with sp hybridized bonding, commonly known as carbyne, is presented. 

There are several potential sources of amorphous materials in chondrite matrices, including interstellar materials, the products of disequilibrium condensation in the nebula, or shock processing of crystalline materials by nebular shock waves. 

Chemical and processing towers, condensers. Furnace parts such as retorts and low stressed parts subject to temperatures up to 800 "C. Type 430 nitric-acid storage tanks, furnace parts, fan scrolls. Type 430F-pump shafts, instrument parts, valve parts Products requiring high yield point and resistance to shock... 

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