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Nonlocal effect

Radioactive material from the Chernobyl accident became widely dispersed throughout Europe and the Northern hemisphere. In Europe alone, about 80,000 TBq of Cs was deposited as follows Belarus 33.5%, Russia 24%, Ukraine 20%, Sweden 4.4%, Finland 4.3%, Bulgaria 2.8%, Austria 2.7%, Norway 2.3%, Romania 2%, and Germany 1.1%. It is probable that the full impact of the Chernobyl reactor accident on natural resources will not be known for several decades, primarily because of data gaps on long-term genetic and reproductive effects and on radiocesium cycling and toxicokinetics. [Pg.704]


Substituting (5.34) and (5.35) for (5.8) and dropping in Z the constant partition function of unperturbed harmonic oscillator we get the nonlocal effective action derived by Feynman (see also Caldeira and Leggett [1983]),... [Pg.81]

A disadvantage of the two-state methods is that modelling of a real potential energy surface (PES) by a TLS cannot always been done. Moreover, this truncated treatment does not cover the high-temperature regime since the truncation scheme does not hold at T> coq. With the assumption that transition is incoherent, similar approximations can be worked out immediately from the nonlocal effective action, as shown in Sethna [1981] and Chakraborty et al. [1988] for T = 0, and in Gillan [1987] for the classical heat bath. [Pg.89]

Numerical solution of Eq. (51) was carried out for a nonlocal effective Hamiltonian as well as for the approximated local Hamiltonian obtained by applying a gradient expansion. It was demonstrated that the nonlocal effective Hamiltonian represents quite well the lateral variation of the film density distribution. The results obtained showed also that the film behavior on the inhomogeneous substrate depends crucially on the temperature regime. Note that the film exhibits different wetting temperatures on both parts of the surface. For chemical potential below the bulk coexistence value the film thickness on both parts of the surface tends to appropriate assymptotic values at x cx) and obeys the power law x. Such a behavior of the film thickness is a consequence of van der Waals tails. The above result is valid when both parts of the surface exhibit either continuous (critical) or first-order wetting. [Pg.282]

The effects of covalently attaching a sulfhydryl-specific reagent to an accessible cysteine are due to local steric or electrostatic effects in the binding site and not due to nonlocal effects. [Pg.442]

What does all of the above analysis teach us First and above ail, the correct LR behavior at the FEG limit is vital for design of a good EDF. Second, proper sum rules should be satisfied to build in systematic error cancellation. Third, the introduction of a weight function releases the constraints on the original formulas at the FEG limit, allows any nonlocal effects to be modeled, and somewhat more importantly, provides a new degree of freedom so that other restrictions can be simultaneously satisfied. Fourth, any recursion should be avoided to permit more efficient implementation. This in turn calls for a better understanding of the TBFWV. Finally, the O(M ) numerical barrier must be overcome so that any general application will be possible. [Pg.146]

The symmetry changes of the vortex lattice in borocarbide superconductors affect their pinning properties as was shown for YNi2B2C (Silhanek et al. 2001). For the field orientation // c, the reorientation transition of the vortex lattice mentioned above was found to be associated with a significant kink in the volume pinning force Fp, whereas in the basal plane (for H c) the signature of nonlocal effects is a fourfold periodicity of Fp. [Pg.275]

This example shows the degree of complication inherent in the nonlocal extension of the continuum theory even for the simplest Born-like case. In accord with Equation (1.141), the dimensionless parameter A/a measures the importance of nonlocality effects the local Born limit is recovered when A/a - 0. The opposite strongly nonlocal limit a/A - 0 corresponds to the unscreened solvation Usoly = -Q2( 1 - 1 /e /la. For the general form of the dielectric function a(k) a numerical solution for one-dimensional Equation (1.144) is straightforward [19]. However, there exists a principal difficulty hindering such solution when a(k) has poles on the real A-axis (see Sections 1.6.7 and 1.6.8). This creates oscillating kernels a f — r ) in the real space. [Pg.103]

Although quite obvious, it is important to remark that a perfect conductor-like model completely neglects the chemical nature of the metal (i.e., all the metals behave in the same way). This is different to what happens for solvents, where even the simplest models include at least one solvent-specific parameter, the static dielectric constant. However, the chemical nature of the metal is relevant for another aspect of the static dielectric response that is neglected by the conductor model the nonlocal effects. They will be discussed in the following Section, The Response Properties of a Molecule Close to a Metal Specimen Surface Enhanced Phenomena and Related Continuum Models. [Pg.306]

Concerning the use of DFT to treat metal-molecule interactions, we remark that present exchange-correlation functionals give rise to difficulties in properly treating dispersion interactions, and the extension of the works on CMs in this direction (e.g., improving the description of the solid response, by including surface and nonlocal effects) seems a promising field. [Pg.306]

In the language of reciprocal space, nonlocal metal response refers to the dependence of the metal dielectric constant on the wavevector k of the various plane waves into which any probing electric fields can be decomposed. Such an effect is often mentioned in reports on SERS, but it is usually neglected. One of the oldest papers addressing the importance of nonlocal effects on the polarizability of an adsorbed molecule is the article by Antoniewicz, who studied the static polarizability of a polarizable point dipole close to a linearized Thomas-Fermi metal [63], The static dielectric constant eTF(k) of such a model metal can be written as ... [Pg.308]

The reported results show that the inclusion of the gradient corrected nonlocal effects is recommended to obtain data consistent with the maximum hardness principle. In fact, in the case of isomerization of HSiN the calculated hardness value for TS is higher than that of the minimum when local VWN potential is used. The introduction of the nonlocal corrections removes this error. The results for all... [Pg.286]

Properties of supported catalysts by bimetallic substrates depend on the changes in geometry of the catalyst material by the strain of the substrate. Using a bimetallic substrate multiphes the possibilities to tune the catalyst to specific requirements. The chemistry of the nanosized overlayer is affected by the different orbital overlaps of atoms from the catalyst cluster and those from the substrate. Additionally, small supported metallic islands show low coordination and reduced near-neighbor distances thus their chemical properties are different with respect to those of flat surfaces. " Reactivity of several bimetallics were also studied by Balbuena et al., including bimetallics systems . Norskov et al. found several relations for the bimetallic systems considering local and nonlocal effects have also been reported. ... [Pg.205]

Dzhavakhidze, P.G., Kornyshev, A.A., and Krishtalik, LI. (1987) Activation energy of electrode reactions the nonlocal effects. Journal of Electroanalytical Chemistry, 228, 329-346. [Pg.129]

Even minor nonlocal effects, A 0.5-1 A also drastically modify the reorganization free energy ratio for homogeneous and electrochemical... [Pg.259]


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See also in sourсe #XX -- [ Pg.278 ]




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