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Finite standard model

As expected, for p — 0, this model reduces again to the zeroth-order hyperbolic model, Eq. (95), but for any finite p, it does not simplify to any of the standard models in the literature. [Pg.237]

The theory of baryogenesis requires new physics beyond the standard model. Fortunately, we already have nice hits universality of three gauge couplings, the discovery of a finite neutrino mass, and recent results from WMAP, indicating convincing evidence for the dark matter, presumably some sort of still unknown elementary particles. [Pg.85]

The quantum chemical standard model for the inclusion of finite-temperature... [Pg.432]

On closer inspection, relatively more accurate values for the tempemture peak and mean degree of cure have been found using the finite-element model, which has provided an overestimated value of the standard degree of cure. The finite-difference model seems to provide underestimated values for all parameters considered however, both analyses produce good agreement with experimental values. [Pg.385]

It is well known that for heavy atoms the effect of the finite nucleus charge distribution has to be taken into account (among other effects) in order to describe the electronic structure of the system correctly (see e.g. (36,37)). As a preliminary step in the search for the effect of the finite nuclei on the properties of molecules the potential energy curve of the Th 73+ has been calculated for point-like and finite nuclei models (Table 5). For finite nuclei the Fermi charge distribution with the standard value of the skin thickness parameter was adopted (t = 2.30 fm) (38,39). [Pg.8]

A remark should be made here with respect to the generation and adjustment of the widely used effective core potentials (ECP, or pseudopotentials) [85] in standard non-relativistic quantum chemical calculations for atoms and molecules. The ECP, which is an effective one-electron operator, allows one to avoid the explicit treatment of the atomic cores (valence-only calculations) and, more important in the present context, to include easily the major scalar relativistic effects in a formally non-relativistic approach. In general, the parameters entering the expression for the ECP are adjusted to data obtained from numerical atomic reference calculations. For heavy and superheavy elements, these reference calculations should be performed not with the PNC, but with a finite nucleus model instead [86]. The reader is referred to e.g. [87-89], where the two-parameter Fermi-type model was used in the adjustment of energy-conserving pseudopotentials. [Pg.243]

Relaxation times are commonly measured for porous media that have been saturated with a fluid such as water or an aqueous brine solution. The observed relaxation times are strongly dependent on the pore size, the distribution of pore sizes, the type of material (e.g. content of paramagnetic ions) and the water content. While relaxation times in porous media have been modelled using random walk methods and finite-element methods, simplified models are usually needed to obtain information on pore space. Section 3.2 reviews the standard model used to analyse relaxation behaviour of fluid in macroporous samples such as rocks. Mesoporous materials such as porous silica will be discussed in Section 3.3. [Pg.274]

To measure load distribution, standard aerospace bolts were fitted with strain gauges. Both shear and axial load could be measured. A three-dimensional finite element model with linear elastic material properties was developed for calculation of load distribution prior to initiation of material failure and comparison with instm-mented bolt results. Model details are similar to those of the single-bolt model above, with a full contact analysis being performed for all bolts, washers and holes. [Pg.313]

The MAC method, which allows arbitrary free surface flows to be simulated, is widely used and can be readily extended to three dimensions. Its drawback lies in the fact that it is computationally demanding to trace a large number of particles, especially in 3D simulation. In addition, it may result in some regions void of particles because the density of particles is finite. The impact of the MAC method is much beyond its interface capmring scheme. The staggered mesh layout and other features of MAC have become a standard model for many other Eulerian codes (even numerical techniques involving mono-phase flows). [Pg.347]

In addition, an adjustment to the specific sample geometries in various applications is needed. There are a number of crucial aspects for a successful translation of SMP technology into industrial applications, such as a standardization of the different methods described for quantification of the shape-memory properties. The recently reported 3-D thermomechanical constitutive model assuming active and frozen phases, representing the multiphase character of thermoplastic SMPs can be an especially fruitful approach for the future development of finite element models for prediction of the thermomechanical behavior. [Pg.143]

K — Z /c in Hartree atomic units). Consequently, the standard Coulomb model for the electron-nucleus attraction can only be employed for atoms with Z < c (see dashed line in Figure 6.5) we may study any atom theoretically if we employ a finite-nucleus model. Figure 6.5 presents the resulting ground-state energies. [Pg.230]

In a strict reductionist view there would be no structure. In the standard model of particle theory there would be a system composed of quarks and electrons, and we would have to resort to the full machinery of the standard model for a proper description. Clearly, this would be a case of serious overkill for chemical purposes at the energies available in chemical reactions, the nuclear forces are not accessible, and internal structure of nuclei becomes uninteresting. So from extensive experience we know that we can consider the nuclei as single, positively charged particles, although we do need to take their finite size into account, as discussed previously—and possibly... [Pg.234]

In Fig. 8 we plot electrostatic quantities of penetrable ions a charge density and an electrostatic potential. Unlike the number density, these quantities are not confined to the region jc> 0, and extend to x = -/ as the charge of an ion sticks out. Note how the sharp peak in the charge density for the standard PB model is smoothed-out in the finite-spread model. [Pg.233]


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See also in sourсe #XX -- [ Pg.77 ]




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