Enhanced velocity

R.M.McCready et al.[l] demonstrate that the adding of O.IM NaCl to 0.33 M ammonia hydroxide enhances the deesterification more than twice. The adding of other chlorides, such as KCl, MgCb and CaCb also enhances the reaction. The effectiveness of the ions in relation to the deesterification and rate constant is arranged in the following order Ca>Mg>Na, K. The equal values of pH and ion strength prove that only the specific cation effect is responsible for the enhanced velocity. 

The enhanced velocities possessed by hot atoms dramatically shorten the time scales associated with nonthermal collisions. Approximate recoil F mean thermalization times, , corresponding to simulated MNR conditions have been calculated (4) using the local equilibrium steady-state hot atom kinetic theory (21,22,41). The values can be compared with the mean reactive lifetimes for thermal Reaction 5, , obtained from absolute and MNR sample composition data. At readily accessible moderator concentrations, the were shown to be tenfold or more larger than the , even for very reactive R species. A calculated [/] ratio of 160 was obtained for C2H6 present at 5.0 X lO" mol fraction in C2F6, showing that hot atom moderation is effectively completed prior to the onset of Reaction 5 in this system. 

The parameters utilized for this approach are from Breck [57] for the gases He, H2, CO2, O2, N2 and CH4, Poling [58] for the gases CO, Ar, C2Huniversal force field (UFF) values [59] are used for the surface atoms, as summarized in Table 5.2. This potential difference has been termed the suction energy since a positive W translates to a suction force of the molecule from the outside to the inside of the pore, while a negative W translates to a repulsive force directing the molecule away from the pore [23]. From this, a new transport mechanism is proposed in [23] as suction diffusion , where enhanced velocities are predicted as the gas molecules are sucked into the pore. 

The basic idea (see Fig. 18) is that as the reactants approach, the ion induces a dipole in the neutral. The resulting force accelerates the two bodies toward each other so that the encounter occurs at an enhanced velocity. At a critical distance of closest approach transfer occurs. The freed atom is released at the same speed (or alternatively, energy) that it possessed just before the actual transfer. In receding, the products are now decelerated by the ion-induced dipole force between them. The net effect will be a change by the ion-induced dipole force between them. The net... 

Of the mechanisms which cause the enhanced velocity of particles, the most important is lateral migration or "tubular pinch" [9]. Here, because of inertial forces, the particles migrate away from the walls of capillary where the velocity is lowest (Figure 1). Deformable particles have been shown to concentrate near the tube center, where the velocity is highest [10]. The radial migration velocity is strongly dependent on the ratio of the particle and capillary sizes [11]. 

Narita, T. Gong, J.P. Osada, Y. Enhanced Velocity of Surf actant Binding after the Volume Collapse of an Oppositely Charged Gel. Macromol. Rapid Comm. 18 (1998), pp. 853-854... 

Enhanced velocity (EV) type burners are typically constructed with ported slide-in inserts, typically of nickel or brass, supported by extruded aluminum bodies with internal water-cooling channels (see Figure 6.1). 

A similar algorithm has been used to sample the equilibrium distribution [p,(r )] in the conformational optimization of a tetrapeptide[5] and atomic clusters at low temperature.[6] It was found that when g > 1 the search of conformational space was greatly enhanced over standard Metropolis Monte Carlo methods. In this form, the velocity distribution can be thought to be Maxwellian. 

Flotation reagents are used in the froth flotation process to (/) enhance hydrophobicity, (2) control selectivity, (J) enhance recovery and grade, and (4) affect the velocity (kinetics) of the separation process. These chemicals are classified based on utili2ation collector, frother, auxiUary reagent, or based on reagent chemistry polar, nonpolar, and anionic, cationic, nonionic, and amphoteric. The active groups of the reagent molecules are typically carboxylates, xanthates, sulfates or sulfonates, and ammonium salts. 

Multiphoton Absorption and Ionization. High laser powers can induce the simultaneous absorption of two or more photons that together provide the energy necessary to excite a transition this transition may be one that is forbidden as a single-photon process (8,297). Such absorption can be made Doppler-free by propagating two laser beams of frequency V in opposite directions, so the Doppler shifts cancel and a two-photon transition occurs at 2v for any absorber velocity. The signal is strong because aU absorbers contribute, and peak ampHtudes are enhanced by, which may... 

Convection heat transfer is dependent largely on the relative velocity between the warm gas and the drying surface. Interest in pulse combustion heat sources anticipates that high frequency reversals of gas flow direction relative to wet material in dispersed-particle dryers can maintain higher gas velocities around the particles for longer periods than possible ia simple cocurrent dryers. This technique is thus expected to enhance heat- and mass-transfer performance. This is apart from the concept that mechanical stresses iaduced ia material by rapid directional reversals of gas flow promote particle deagglomeration, dispersion, and Hquid stream breakup iato fine droplets. Commercial appHcations are needed to confirm the economic value of pulse combustion for drying. 

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