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Nearest modeling

Beagle dogs show a high incidence of epileptic seizures, including those of the secondary type complex partial and generalized tonic-clonic seizures frequently occur in this species. However, the nearest model to... [Pg.298]

The Ad]q2 first step produces an ion pair that would be expected to have a p abH near 12. Our nearest model, choline p Ta = 13.9, is expected to be less acidic because it has an extra methylene (CH3)3N" CH2CH20H. The incoming nucleophile (conjugate base p a = 10.6) is only slightly less basic than the ion pair produced by the addition. The Adf 2 second step also removes the proton from acetic acid, p/STg = 4.8, thereby creating a weaker base, so both steps pass our crosschecks. [Pg.282]

Our discussion of solids and alloys is mainly confined to the Ising model and to systems that are isomorphic to it. This model considers a periodic lattice of N sites of any given symmetry in which a spin variable. S j = 1 is associated with each site and interactions between sites are confined only to those between nearest neighbours. The total potential energy of interaction... [Pg.519]

An alternative fomuilation of the nearest-neighbour Ising model is to consider the number of up f T land down [i] spins, the numbers of nearest-neighbour pairs of spins IT 11- U fl- IT Hand their distribution over the lattice sites. Not all of the spin densities are independent since... [Pg.523]

The Ising model is isomorphic with the lattice gas and with the nearest-neighbour model for a binary alloy, enabling the solution for one to be transcribed into solutions for the others. The tlnee problems are thus essentially one and the same problem, which emphasizes the importance of the Ising model in developing our understanding not only of ferromagnets but other systems as well. [Pg.524]

The relationship between tlie lattice gas and the Ising model is also transparent in the alternative fomuilation of the problem, in temis of the number of down spins [i] and pairs of nearest-neighbour down spins [ii]. For a given degree of site occupation [i]. [Pg.526]

A binary alloy of two components A and B with nearest-neighbour interactions respectively, is also isomorphic with the Ising model. This is easily seen on associating spin up with atom A and spin down with atom B. There are no vacant sites, and the occupation numbers of the site are defined by... [Pg.527]

In the simplest model the eoeflfieient K depends only on the differenees of the attraetive energies -e of the nearest-neighbour pairs (these energies are negative relative to those of the isolated atoms, but here their magnitudes e are expressed as positive numbers)... [Pg.628]

Slightly more complex models treat the water, the amphiphile and the oil as tliree distinct variables corresponding to the spin variables. S = +1, 0, and -1. The most general Hamiltonian with nearest-neighboiir interactions has the fomi... [Pg.2379]

The nearest thing to a complete justification of equations (11.3)i for pellets of arbitrary shape, is an argument given by W. E. Stewart [74], which does not depend on any particular choice of flux relations. In Chapter 10 it was pointed out that all isothermal flux models must have the general form... [Pg.141]

The primary structure of a peptide is its ammo acid sequence We also speak of the secondary structure of a peptide that is the conformational relationship of nearest neighbor ammo acids with respect to each other On the basis of X ray crystallographic studies and careful examination of molecular models Linus Pauling and Robert B Corey of the California Institute of Technology showed that certain peptide conformations were more stable than others Two arrangements the a helix and the (5 sheet, stand out as... [Pg.1143]

Enthalpies of mixing have their origin in the forces that operate between individual molecules. Intermolecular forces drop off rapidly with increasing distance of separation between molecules. This means that only nearest neighbors need be considered in the model. [Pg.521]

Dispersion modeling of credible worse case scenarios indicates the one-hour exposure to nearest human receptor exceeds ERPG-2 level or equivalent. [Pg.178]

It is evident that an approximate — 1.5cr shift ean be determined from the data and so the Cpi value is more suitable as a model. Using the graph on Figure 6, whieh shows the relationship Cp, (at 1.5cr shift) and parts-per-million (ppm) failure at the nearest limit, the likely annual failure rate of the produet ean be ealeulated. The figure has been eonstrueted using the Standard Normal Distribution (SND) for various limits. The number of eomponents that would fall out of toleranee at the nearest limit, is potentially 30 000 ppm at = 0.62, that is, 750 eomponents of the 25 000 manufaetured per annum. Of eourse, aetion in the form of a proeess eap-ability study would prevent further out of toleranee eomponents from being produeed and avoid this failure rate in the future and a target Cp = 1.33 would be aimed for. [Pg.294]

Thus, the user can input the minimum site boundary distance as the minimum distance for calculation and obtain a concentration estimate at the site boundary and beyond, while ignoring distances less than the site boundary. If the automated distance array is used, then the SCREEN model will use an iteration routine to determine the maximum value and associated distance to the nearest meter. If the minimum and maximum distances entered do not encompass the true maximum concentration, then the maximum value calculated by SCREEN may not be the true maximum. Therefore, it is recommended that the maximum distance be set sufficiently large initially to ensure that the maximum concentration is found. This distance will depend on the source, and some trial and error may be necessary however, the user can input a distance of 50,000 m to examine the entire array. The iteration routine stops after 50 iterations and prints out a message if the maximum is not found. Also, since there may be several local maxima in the concentration distribution associated with different wind speeds, it is possible that SCREEN will not identify the overall maximum in its iteration. This is not likely to be a frequent occurrence, but will be more likely for stability classes C and D due to the larger number of wind speeds examined. [Pg.306]

Here we review the properties of the model in the mean field theory [328] of the system with the quantum APR Hamiltonian (41). This consists of considering a single quantum rotator in the mean field of its six nearest neighbors and finding a self-consistent condition for the order parameter. Solving the latter condition, the phase boundary and also the order of the transition can be obtained. The mean-field approximation is similar in spirit to that used in Refs. 340,341 for the case of 3D rotators. [Pg.117]

In their model they retained only the first- and second-nearest neighbor interactions, so that the Hamiltonian assumed the following form... [Pg.255]

Assuming that the interaction between the adsorbed particles is confined to the first nearest neighbors, the Hamiltonian of the model reads... [Pg.272]


See other pages where Nearest modeling is mentioned: [Pg.184]    [Pg.230]    [Pg.103]    [Pg.184]    [Pg.230]    [Pg.103]    [Pg.487]    [Pg.561]    [Pg.593]    [Pg.2379]    [Pg.2749]    [Pg.214]    [Pg.727]    [Pg.467]    [Pg.411]    [Pg.28]    [Pg.3]    [Pg.141]    [Pg.366]    [Pg.376]    [Pg.377]    [Pg.378]    [Pg.174]    [Pg.425]    [Pg.63]    [Pg.79]    [Pg.154]    [Pg.322]    [Pg.39]    [Pg.129]    [Pg.134]    [Pg.313]    [Pg.63]    [Pg.64]    [Pg.86]    [Pg.110]   
See also in sourсe #XX -- [ Pg.392 ]




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