Propagation regime

Biernath et al. concluded that phenolic novolac and epoxidized cresol novolac cure reactions using triphenylphosphine as the catalyst had a short initiation period wherein the concentration of phenolate ion increased, followed by a (steady-state) propagation regime where the number of reactive phenolate species was constant.85 The epoxy ring opening was reportedly first order in the steady-state regime. 

Ya.B.Zel dovich I.Ya. Shlyapintokh, DoklAkadN 65, 871(1949) (The reaction propagation regime in an expl gaseous mixture, being similar in its mechanism to spin detonation, was studied, making use... 

The limit of existence of the uniform propagation regime of the flame is reached at 6 = Uo/2e, and at the limit... 

Combining the first two basic equations of a steadily propagating regime, specifically the equations of conservation of mass and momentum, so as to obtain the equation... 

If we seek a strictly steady detonation propagation regime in which the entire phenomenon moves in space with a single specific and constant velocity, it is obvious that the shock wave igniting the gas must satisfy one and only one condition—it must propagate in the gas with the same velocity as that of the detonation. 

G. Mechain, A. Couairon, Y.-B. Andre, C. D amico, M. Franco, B. Prade, S. Tzortzakis, A. Mysyrowicz, R. Sauerbrey, Long-range self-channeling of infrared laser pulses in air a new propagation regime without ionization, Applied Physics B 79, 379 (2004)... 

Within the region of optimal experimental parameters, the combustion wave velocity remains constant and the temperature profile T(t) has the same form at each point of the reaction medium. This regime is called steady propagation of the combustion synthesis wave, or steady SHS process. As the reaction conditions move away from the optimum, where the heat evolution decreases and/or heat losses increase, different types of unsteady propagation regimes have been observed. These include the appearance of an oscillating combustion synthesis... 

Agrafiotis, C. C Puszynski, J. A., and Hlavacek, V., Experimental study on the synthesis of titanium and tantalum nitrides in the self-propagating regime. Combust. Sci. Tech., 76, 187 (1991). 

It has been proven by other authors that the P-relaxation is the mechanism governing the craze formation process for stationary as well as for propagating crazes in the slow crack speed region Furthermore, also from crack speed measurements (K, vs a) in the slow propagation regime performed on PMMA in the temperature range of —60 °C to -1-80 an activation energy appropriate for the P-process has been derived... 

Figure 12.2 Time histories of pressure peaks of the direct initiation processes of cylindrical detonations in a mixture of H2 + 02+7Ar with three different propagation regimes (a) supercritical (Es = 76.3 J/cm), (6) critical Es = 53.0 J/cm), and (c) subcritical (Es = 33.9 J/cm), depending on the deposited initiation energy.

Figure 12.4 Velocity profiles of (o) supercritical Es = 76.3 J/cm) and (6) subcrit-ical Eg = 33.9 J/cm) propagation regimes at direct detonation initiation.

In the second case we suggested the model which describes qualitatively the transition to the second propagation regime. 

Y. Wu, and X. X. Yang. Highly efficient four-wave mixing in double- A system in ultraslow propagation regime. Physical Revew A 2004 Nov 18 70(5) 053818(5). 

Based on the DSC and microdielectrometry studies, the kinetics of the TPP catalyzed epoiy-phenol reaction can be described through an initiation regime and a "steady state" propagation regime. Diffusion limitations do not appear to have substantial influence within the temperature range of interest. 

The transition-limited regime or the propagation regime, when positron motion can be described as Bloch wave propagation. Positron trapping in monovacancies is an example of the transition-limited regime [101]. 

FIGURE 30.10 E)ata from all experiments already shown in Figure 30.9, but plotted with Kmai as the presumed FCP parameter. AU data in the stable crack propagation regime collapse to the same curve, confirming K, as the FCP parameter for this regime of crack growth. 

The sensitivity of nitroglycerol decreases with temperature. However, frozen it is sensitive to friction due to inteicrystalline contact. It decomposes above 60 °C. It exhibits a low-velocity propagation regime with a detonation rate of about 2000 m/s compared with its high-eneigy detonation rate of about 7800 m/s. 

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