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Energy limit

The authors are grateful to Dr J M Farley of Mitsui Babcock Energy Limited for useful comments. [Pg.956]

Again, the reaction requires a minimum collision energy Eq, but increases only gradually above the tln-eshold towards a finite, high-energy limit... [Pg.778]

Only in the high-energy limit does classical statistical mechanics give accurate values for the sum and density of states tenns in equation (A3.12.15) [3,14]. Thus, to detennine an accurate RRKM lc(E) for the general case, quantum statistical mechanics must be used. Since it is difficult to make anliannonic corrections, both the molecule and transition state are often assumed to be a collection of hannonic oscillators for calculating the... [Pg.1018]

As we have seen, the electron is the easiest probe to make surface sensitive. For that reason, a number of hybrid teclmiques have been designed that combine the virtues of electrons and of other probes. In particular, electrons and photons (x-rays) have been used together in teclmiques like PD [10] and SEXAFS (or EXAFS, which is the high-energy limit of XAES) [2, Hj. Both of these rely on diffraction by electrons, which have been excited by photons. In the case of PD, the electrons themselves are detected after emission out of the surface, limiting the depth of sampling to that given by the electron mean free path. [Pg.1756]

At strain rates below e, energy-limited spall is expected to proceed through a brittle (fracture dominated) spall mechanism while for strain rates greater than 8, a ductile (flow-dominated) mechanism is expected. [Pg.289]

In an electron-excited X-ray spectrum the discrete X-ray lines are superimposed on a continuous background this is the well-known bremsstrahlung continuum ranging from 0 to the primary energy Eq of the electrons. The reason for this continuum is that because of the fundamental laws of electrodynamics, electrons emit X-rays when they are decelerated in the Coulomb field of an atom. As a result the upper energy limit of X-ray quanta is identical with the primary electron energy. [Pg.196]

The extrapolation to the complete basis set energy limit is based upon the MoUer-Plesset expansion E= + E + E + E + E +. .. as described earlier in this appendix. Recall that E + E is the Hartree-Fock energy. We will denote E and all higher terms as E , resulting in this expression for E ... [Pg.278]

In addition to measuring total recombination coefficients, experimentalists seek to determine absolute or relative yields of specific recombination products by emission spectroscopy, laser induced fluorescence, and optical absorption. In most such measurements, the products suffer many collisions between their creation and detection and nothing can be deduced about their initial translational energies. Limited, but important, information on the kinetic energies of the nascent products can be obtained by examination of the widths of emitted spectral lines and by... [Pg.51]

Integral W values oj ionization for incident electron energies E, as measured in Combecher s (1980) experiments on gaseous water, can be well fitted by the equation W(E) = W(°°)(l - I/E)-1, where W(°°) = 30.0 eV is the value in the high-energy limit. A similar equation is assumed for liquid water. In contrast, the entity-specific Wi value of ionization, defined for a certain energy deposition in a spur, shows a minimum at 20 eV in... [Pg.115]

For the potential given by (5.3), it is easy to show that when b > bc the distance of closest approach is bc /21/2, whereas for b < b, the only thing preventing interpenetration is a repulsive core potential, which is not explicitly considered here. Equation (5.4) is actually the classical collision cross section for the problem. To translate this into a reaction cross section, we may assume that there is another critical separation r0 such that when r < rg chemical forces complete the reaction and no reaction takes place if r > rg. If rg is less than b /2m, then Eq. (5.4) is also the reaction cross section, since reaction definitely takes place if b < b. and it definitely does not take place if b > b.. According to this modification, the high-energy limit of the reaction cross section is nr2 rather than zero as given by (5.4). One therefore has... [Pg.141]

Sedgwick Energy, Limited, An Introduction to Energy Insurance. Sedgwick Energy, Ltd., London, U.K., 1994. [Pg.8]

Sedgwick Energy, "Loss Control Newsletter", Sedgwick Energy Limited, London, U.K. Issue 1,1994. [Pg.61]

A band was observed at 2260 cm- which did not shift as a function of potential, which we assign to v(CN) of solution phase CI CCN nea the electrode surface. We were unable to look for the 1615 cm band reported by Sexton et. al. (20), since this frequency lies beyond the lower energy limit of the InSb detector in our spectrometer, and in a spectral region where there is severe background absorbance by the H O solvent. [Pg.374]

In its equilibrium form, Gsc is the free energy limit most frequently interfaced to ab initio quantum chemistry packages[34], while GBO is more common in outer sphere electron transfer studies[35]. [Pg.264]

Somewhat different proportions will apply for other materials but the picture will be similar. The energy limits are based on sound reasoning but Include some Intuition and there Is a statistical distribution of events and distributions. [Pg.18]

Several methods have been developed for establishing the MP2 limit for small molecules. We shall compare three of the most important methods, and a recently proposed combination of two of them that achieves a new level of efficiency in obtaining chemically accurate absolute MP2 energy limits. We conclude with a case study of the extension of these approaches to enzyme kinetics, namely the A5-ketosteroid isomerase-catalyzed conversion of A5-androstene-3,17-dione to the A4 isomer. [Pg.100]

P is the eentral quantity in the GW method, and earries many-hody effeets heyond the HF approximation. In the limit P O, the self-energy limits to... [Pg.41]


See other pages where Energy limit is mentioned: [Pg.1013]    [Pg.1027]    [Pg.2022]    [Pg.387]    [Pg.155]    [Pg.145]    [Pg.154]    [Pg.786]    [Pg.284]    [Pg.284]    [Pg.288]    [Pg.288]    [Pg.300]    [Pg.137]    [Pg.802]    [Pg.125]    [Pg.315]    [Pg.316]    [Pg.85]    [Pg.88]    [Pg.20]    [Pg.124]    [Pg.331]    [Pg.45]    [Pg.108]    [Pg.481]    [Pg.327]    [Pg.572]    [Pg.373]    [Pg.60]    [Pg.110]    [Pg.278]    [Pg.93]   
See also in sourсe #XX -- [ Pg.113 ]

See also in sourсe #XX -- [ Pg.89 ]




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Activation energy diffusion-limited

Activation energy second limit

Activation energy thermodynamic limitations

Activation energy, apparent thermodynamic limitations

Apparent activation energy rate limiting steps

Atomic Energy of Canada Limited

Atomic Energy of Canada Limited AECL)

Bond dissociation energies limited conditions

Bond dissociation energy limitations

British Energy Generation Limited

Charging Energy Limited Tunneling CELT)

Correlation energy density limit

Diffusion limited energy migration

Electron energy loss spectroscopy limitations

Energy transfer limited reactions

Energy transfer rapid diffusion limit

Energy-Transfer-Limited Processes

Exchange-correlation energy limit

FOSSIL FUELS ARE A WIDELY USED BUT LIMITED ENERGY SOURCE

Inherently energy limitation

Ionic limit bond energy

Limitation energy

Limitation energy

Limitation energy transfers

Limitation of energy

Limited energy apparatus

Potential energy surfaces limitations

Rapid energy exchange limit

Reaction paths, potential energy surfaces limitations

Resonance energy transfer limitations

Spin resolution, correlation energy uniform density limit

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The Theoretical Limit of Energy Per Unit Weight

Total Energies and the Hartree-Fock Limit

Uniform density limit energy

Uniform density limit energy functionals

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