Confinement parameter

The size of the soliton pair as on Fig. 6a is determined by the so-called confinement parameter y = Ae/(2XAo) [27,29]. Its meaning is qualitatively quite clear If the energy difference AE between the two structures increases, the extension of the high-energy one decreases and the pair is more confined. For very small y (i.e., Ae 0), the soliton pair or the bipolaron will tend to dissociate into independent solitons or polarons. 

A measure of the suecess of a machine in producing useful fusion energy is known as the Lawson confinement parameter, the product of the density of particles in the plasma and the time the particles are confined. That is, in order for controlled fusion to occur, particles in the plasma must be brought close together and they must be kept together for some critical period of time. All of this must take place, of course, at a temperature at which fusion can occur. 

Fig. 14.1 Scheme and plots illustrating the dependence of nanoscale-confinement parameters T and/on the radius 6 of the osculating sphere at the protein-water interface. First-order contacts with a polar or nonpolar patch on the protein surface are treated individually. Values were determined at equilibrium obtained by integrating Newton s equations of motion in an NPT ensemble with box size 103 nm3, starting with the PDB structure embedded in a pre-equilibrated cell of water molecules. The box size was calibrated so that the solvation shell extended at least 10 A from the protein surface at all times. Simulations were performed as described in Chap. 4... 

Fig. 2 Confinement parameter n QX needed to ignite a 50% D-50% T toroidal plasma column, having the parameters of case a) of Table I, versus the central temperature T q, for different values of < A parabolic profile is...

The photoluminescence spectrum observed in polythiophene can be fitted from this model leading to the S Huang-Rhys number (and consequently to the confinement parameter y), to the relative intensity of the peaks and to the position of the peaks relative to the energy gap. An example of calculated photoluminescence spectrum of polythiophene is given in Figure 14.13 [109]. 

In the continuum models of Brazovskii and Kirova [35] and Fesser et al. [36] (the FBC model), the preferred sense of bond alternation is introduced through an extrinsic contribution to the gap parameter A. sls A = zlo + Je. where Aq is the contribution to the gap due to the Peierls mechanism and Je is the extrinsic contribution. It is useful to define a confinement parameter y, as y = AJ2 A, where A is the effective electron-phonon coupling constant such that A = exp[y]. 

Figure Bl.22.4. Differential IR absorption spectra from a metal-oxide silicon field-effect transistor (MOSFET) as a fiinction of gate voltage (or inversion layer density, n, which is the parameter reported in the figure). Clear peaks are seen in these spectra for the 0-1, 0-2 and 0-3 inter-electric-field subband transitions that develop for charge carriers when confined to a narrow (<100 A) region near the oxide-semiconductor interface. The inset shows a schematic representation of the attenuated total reflection (ATR) arrangement used in these experiments. These data provide an example of the use of ATR IR spectroscopy for the probing of electronic states in semiconductor surfaces [44]-...

A logical consequence of this trend is a quantum w ell laser in which tire active region is reduced furtlier, to less tlian 10 nm. The 2D carrier confinement in tire wells (fonned by tire CB and VB discontinuities) changes many basic semiconductor parameters, in particular tire density of states in tire CB and VB, which is greatly reduced in quantum well lasers. This makes it easier to achieve population inversion and results in a significant reduction in tire tlireshold carrier density. Indeed, quantum well lasers are characterized by tlireshold current densities lower tlian 100 A cm . ... 

Grimitlyn, M. 1., and G. M. Pozin. 1973. Determination of parameters of the jet developing iri a confined space and following a blocked or through-motion pattern. In Proceedings of VTsNliOT VTsSPS 91. Profizdat, Moscow. 

Evaluation of experimental data from work covered in Section 4.1 tends to confirm this concludion. These data indicate that, for quiescent clouds, both the scale and strength of a blast are unrelated to fuel quantity present in a cloud. These parameters are, in fact, determined primarily by the size and nature of partially confined and obstracted regions within the cloud. The factor of reactivity of the fuel-air mixture is of only secondary influence. 

Interpretations may be ephemeral, but experimental data are permanent. To conserve space, the collection of kinetic data presented here is confined to studies which include the determination of at least one activation parameter. For kinetic studies reporting rate constants at a single temperature the following references should be consulted 21, 23, 27, 29(b), 30, 31, 33-39, 44, 46, 48, 52, 81, 86, 92, 96, 99, 141, and 142, as well as some of the tables in this review. Among the excluded studies, those involving catalytic phenomena are especially worthy of mention. 

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