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State description

Computations done in imaginary time can yield an excited-state energy by a transformation of the energy decay curve. If an accurate description of the ground state is already available, an excited-state description can be obtained by forcing the wave function to be orthogonal to the ground-state wave function. [Pg.219]

It, therefore, appears that the equilibrium approximation is a special case of the steady-state approximation, namely, the case i > 2- This may be, but it is possible for the equilibrium approximation to be valid when the steady-state approximation is not. Consider the extreme but real example of an acid-base preequilibrium, which on the time scale of the following slow step is practically instantaneous. Suppose some kind of forcing function were to be applied to c, causing it to undergo large and sudden variations then Cb would follow Ca almost immediately, according to Eq. (3-153). The equilibrium description would be veiy accurate, but the wide variations in Cb would vitiate the steady-state description. There appear to be three classes of practical behavior, as defined by these conditions ... [Pg.105]

General considerations of data availability lead immediately to the recognition that detection systems are more likely to be designed as comprehensive numeric-symbolic interpreters as illustrated in Fig. 3. State description systems may be configured as shown in either Fig. 3 or Fig. 4. Fault classification systems are most likely to require the symbolic-symbolic mapping to compensate for limited data as shown in Fig. 4. Many practical data interpretation problems involve all three kinds of interpreters. In all situations, there is a clear need for interpretation systems to adapt to and evolve with changing process conditions and ever-increasing experience. [Pg.44]

With the view that a KBS interpreter is a method for mapping from input data in the form of intermediate symbolic state descriptions to labels of interest, four families of approaches are described here, each offering inference mechanisms and related knowledge representations that can be used to solve interpretation problems namely, model-based approaches, digraphs, fault trees, and tables. These methods have been heavily used... [Pg.67]

The basis in which P is of the above form is made of the collection of occupied and unoccupied eigenstates i.e. (occupied), (unoccupied) - Ultimately, the very process of projection allows one to select the N occupied ones, and it is not necessary to consider the unoccupied ones (at least for the ground-state description of the system). [Pg.144]

In order to improve the quality of excited state description, correlation needs to be included. The methods having been developed can be categorized into two groups, the multireference methods, and the single-reference based methods. [Pg.290]

From this fundamental level the model can be advanced to more complex levels. Inclusion of the dynamics of flow or transfer rates between compartments and degradation properties within compartments can transform the model to a nonequilibrium, steady state description of a chemical s fate. [Pg.118]

State Description Storage capacity Initial amount... [Pg.63]

The Raman effect arises when a photon is incident on a molecule and interacts with the electric dipole of the molecule. In classical terms, the interaction can be viewed as a perturbation of the molecule s electric field. In quantum mechanics the scattering is described as an excitation to a virtual state lower in energy than a real electronic transition with nearly coincident de-excitation and a change in vibrational energy. The scattering event occurs in 10 14 seconds or less. The virtual state description of scattering is shown in Figure 1. [Pg.241]

Figure 2.15 Pressure-volume data for diamond, SiC>2-stishovite, MgSiC>3 and 8102-quartz based on third order Birch-Murnaghan equation of state descriptions. The isothermal bulk modulus at 1 bar and 298 K are given in the figure. Figure 2.15 Pressure-volume data for diamond, SiC>2-stishovite, MgSiC>3 and 8102-quartz based on third order Birch-Murnaghan equation of state descriptions. The isothermal bulk modulus at 1 bar and 298 K are given in the figure.
This also ascribes a meaning to the other KS orbital energies. Without a reasonable description of the other ionization potentials, many excited state descriptions will fail because most excited states for molecules are of Rydberg character, or require some mixture of Rydberg character in their accurate description. [Pg.283]

Heisig M, Lieckfeldt R, Wittum G, Mazurkevich G, Lee G (1996) Non steady-state descriptions of drug permeation through stratum comeum. I. The biphasic brick-and-mortar model. Pharm Res 13 421 —426. [Pg.484]

If we choose only one determinant built from the lowest /2 SCF-orbitals, the "configuration interaction method will naturally give us Wq = Ao with the energy eigenvalue q as the best groimd-state description. This is clearly identical with the SCF result of the last section. [Pg.7]

The Steady-State Mechanism If the interconversion step is not the sole rate-determining step and binding steps are not in rapid equilibrium, then a steady-state description of the reaction is applicable. If there is a single ternary complex, EXY, (thus, [EXY] = [EAB] + [EPQ]), the scheme can be depicted as... [Pg.525]

The results for the apparent radius of STM images for individual states can be used to interpret experimental images directly. For surfaces with complex periodic structures, such as Si(lll)-7 X 7 and Si(lll)-5 X 5, the concept of imaging individual atomic states is a much better description than surface Bloch functions. For adatoms and defects, the individual state description is the only possible one. [Pg.155]

The desired state description was adopted with slight modification ... [Pg.509]

A dynamic rotational isomeric state description is presented of a,high frequency dielectric dispersion. [Pg.43]

Formula State Description Qf, heal, mokr1 Q, keal. moler1 ... [Pg.17]


See other pages where State description is mentioned: [Pg.231]    [Pg.200]    [Pg.232]    [Pg.6]    [Pg.335]    [Pg.179]    [Pg.262]    [Pg.276]    [Pg.85]    [Pg.264]    [Pg.29]    [Pg.253]    [Pg.146]    [Pg.197]   
See also in sourсe #XX -- [ Pg.177 , Pg.195 ]

See also in sourсe #XX -- [ Pg.2 , Pg.3 ]




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A kinematic description of unsteady-state behaviour

Ab-initio Description of Triplet States

Approximate Description of Excited State PES

Character state descriptions

Description of state

Description of the Solid State

Discrete time state space model description

Equation of state description

Ground state energy description

Intruder states description

Iowa State University description

Metastable states descriptions

Molecular Rydberg states description

Quantum description of steady-state processes

Reaction state, description

Solid state, description

Solid-state Mg NMR spectroscopy description

Steady-state methods, general description

System, description state/patterns

The Macroscopic Description of Nonequilibrium States

Thermodynamic Description of the Equilibrium State

Transition states description

Transition-state theory description

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