Migration mode

The ramifications of this phenomenon on the sintering characteristics of a system where there are only weak interaction forces between the particles and the support become distinct. At temperatures below the Tammann temperature particle growth takes place by the atomic migration mode, and, when this temperature is exceeded, the dominant mode of sintering switches to crystallite migration. 

Scheme 20. B3LYP/6-31 l+G(d,p)//B3LYP/6-31G(d) + AZPE calculated energy barriers (kJ mor ) for the [1,3] and [1,5] migration modes for the 1,1-dimethyl-2-(dimethylphosphatox-y)ethyl radical 81...

An extended Hiickel and ab initio Hartree-Fock calculations for the CO insertion into [Pt(CH3)(CO)F(PH3)] also indicated the methyl migration mode... 

A5. Briefly e5q)lain why the SMB system is much more efficient (i.e., uses less solvent and less adsorbent) than an elution chromatograph doing the same binary separation. Assume that both systems are operating in the migration mode using isocratic elution. Both systems are optimized. The elution chromatograph uses repeated pulses of feed. 

C, the analytes are completely swept by the PS and followed by MEKC separation in the reverse migration mode. Under the optimized condition, 5000-fold enhancements in detection sensitivity were obtained in terms of peak heights by sweeping. 

Figure 4.2. Charge migration modes A and B in stacked molecules with complete charge transfer (CT) (left) and with incomplete charge transfer (right).

The insoluble, hydrophobic disperse dyes readily dye nylon, and because their mode of attraction is completely nonionic they are completely insensitive to chemical variations and pH. Small molecular-sized disperse dyes (ca mol wt 400) show very high rates of diffusion and excellent migration properties and they are insensitive to physical variations in the nylon. As the molecular size of disperse dyes increases they show increasing sensitivity to physical variation. 

Because protein samples are actually ampholytes, when samples are loaded onto the gel and a current is appHed, the compounds migrate through the gel until they come to their isoelectric point where they reach a steady state. This technique measures an intrinsic physicochemical parameter of the protein, the pi, and therefore does not depend on the mode of sample appHcation. The highest sample load of any electrophoretic technique may be used, however, sample load affects the final position of a component band if the load is extremely high, ie, high enough to titrate the gradient ampholytes or distort the local electric field. 

Cross-flow-elec trofiltratiou (CF-EF) is the multifunctional separation process which combines the electrophoretic migration present in elec trofiltration with the particle diffusion and radial-migration forces present in cross-flow filtration (CFF) (microfiltration includes cross-flow filtration as one mode of operation in Membrane Separation Processes which appears later in this section) in order to reduce further the formation of filter cake. Cross-flow-electrofiltratiou can even eliminate the formation of filter cake entirely. This process should find application in the filtration of suspensions when there are charged particles as well as a relatively low conduc tivity in the continuous phase. Low conductivity in the continuous phase is necessary in order to minimize the amount of elec trical power necessaiy to sustain the elec tric field. Low-ionic-strength aqueous media and nonaqueous suspending media fulfill this requirement. 

Tlie growfii and spread of fires occurs fiuough heat transfer or tlie migration of burning materials. There are fiuee main modes of heat transfer conduction, convection, and radiation. 

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