Initial nucleus

Figure B3.3.10. Contour plots of the free energy landscape associated with crystal niicleation for spherical particles with short-range attractions. The axes represent the number of atoms identifiable as belonging to a high-density cluster, and as being in a crystalline environment, respectively, (a) State point significantly below the metastable critical temperature. The niicleation pathway involves simple growth of a crystalline nucleus, (b) State point at the metastable critical temperature. The niicleation pathway is significantly curved, and the initial nucleus is liqiiidlike rather than crystalline. Thanks are due to D Frenkel and P R ten Wolde for this figure. For fiirther details see [189].

Splitting light nuclei (which happens in particle accelerators) costs energy. The total mass of the products therefore, is greater than the total mass of the initial nucleus. 

Growth of the hydrogen bubbles due to gas diffusion directed inside the bubble from the solution and depending on dimensions of the initial nucleus, the initial content of hydrogen in the melt, the amplitude of sound pressure, and duration of cavitation action. 

Organization of myosin in striated-muscle thick filaments. Filament formation begins with tail-to-tail (antiparallel) binding of myosin molecules, with subsequent parallel binding of myosin molecules to the ends of the initial nucleus, leaving the central clear zone. There are approximately 500 myosin molecules per striated thick filament. 

Since 1984, three FES implant models have evolved from the Cochlear s technology and its subsidiary Neopraxis Pty. Ltd. The initial Nucleus FES-22 Stimulator was implanted in 1991 after animal and human studies, and with the U.S. Food and Drug Administration s approval (IDE G87014) and Institutional Review Board (IRB) approval in a 21 yr. Paraplegic Subject (ASIA TIO). 

Matsumoto, Saito and Ohmine. [7] studied freezing of water under constant volume and constant temperature conditions. This does not allow volume fluctuation in the system. Liquid water at low temperature exhibits large-scale density fluctuations, which have been interpreted to mean that there are regions of low-density liquid phase that facilitate initial nucleus formation. These low-density... 

This derivation, which ignores all coherent interference between potentiah and resonance scattering, is the simplest for keeping spin factors in order. We consider a reaction where an incident particle a reacts with an initial nucleus A to form a compound nucleus C, which then decays by one of a number of possible decay modes symbolized hy h- B into an outgoing nuclear subunit, or photon, h, plus a final nucleus B. The final nucleus B and the fragment h may be in their ground states with respect to internal degrees of freedom, or in one of various possible excited states. The assumptions are ... 

Polypropylene can be easily induced to form row structures by extension of the melt. An example of the resultant morphology is shown below. Closely spaced shish-kebab lamellae have grown directly out from the central row nucleus, but as growth proceeds outwards, increasing numbers of cross-hatching lamellae are found. The cross-hatching lamellae are found almost perpendicular to the lamellae growing out from the initial nucleus (Fig. 3.3). 

Fig. 3 The critical sizes of charged clustea- JVf , and Nf. The values of Nf and correspond to the formation of initial nucleus, growth of external branches, and dissociation of charged droplets, respectively...

The number of nuclei formed in time b/G can still be approximated by unity, although the initial nucleus has not spread to fill the entire substrate. It follows that... 

One method that has been used to effect this separation is to invoke the Gibbs-Thomson relation. The interfacial free energy, a c, associated with the basal plane of the mature lamellar crystallite is obtained from the relation between the melting temperature and crystaUite thickness for bulk crystallized polymers. The inherent assumption is then made that a c for the mature crystallite can be identified with of the nucleus. In this manner the separation of the product of interfacial free energy can be achieved. This rather drastic assumption has not been substantiated. There is no requirement that the interfacial structure of a mature crystallite repUcates that of the initiating nucleus. In fact this situation is highly unlikely. 

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