Compressive contact, charging

At a finite distance, where the surface does not come into molecular contact, equilibrium is reached between electrodynamic attractive and electrostatic repulsive forces (secondary minimum). At smaller distance there is a net energy barrier. Once overcome, the combination of strong short-range electrostatic repulsive forces and van der Waals attractive forces leads to a deep primary minimum. Both the height of the barrier and secondary minimum depend on the ionic strength and electrostatic charges. The energy barrier is decreased in the presence of electrolytes (monovalent < divalent [Pg.355]

In placing the charge, fasten it securely on the target, being sure the explosive is in good contact with steel at all points. Insert the blasting cap and compress the explosive firmly around it. 

Intense contact (compression or rubbing) Same as for light contact plus the following Preferential local heating (to cause ion migration or electron transfer) Rupture of chemical bonds (Asymmetry of either surface structure or nature of contact or both is necessary to achieve charging)... 

Fixed bed plants. In this type of plant, the process flow for all three feeds looks like the plant in Figure 20—3. The feed and compressed air are mixed, vaporized in a heater, and then charged to the fixed-bed reactor, a bundle of rubes packed with the catalyst. The ratio of air to hydrocarbon is generally about 75 1 to keep the mixture outside the explosive range, always a good idea. The feed temperature is 800-900°F, depending on the feed. The reaction time is extremely quick, so the feed is in contact with the catalyst for only 0.1 to 1.0 second. 

K, as calcd in Ref 57, p 110, then the gas would ignite if the period of contact, rcont> firedamp with the compression zone is longer than the period of induction, T-n(j (the time elapsing betw expln of charge and ignition of firedamp)... 

CICLOPRAPANO (Spanish) (75-19-4) Flammable compressed liquefied gas. Contact with strong oxidizers can cause fire and explosions. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

If each new charge is healed 18 K by contact with the clearance gases, calculate the maximum temperature attained in the cylinder, assuming adiabatic compression. 

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