Polarizing screen

Fermi (1940) pointed out that as /)—-1 the stopping power would power would approach °° were it not for the fact that polarization screening of one medium electron by another reduced the interaction slightly. This effect is important for the condensed phase and is therefore called the density correction it is denoted by adding -Z<5/2 to the stopping number. Fano s (1963) expression for 8 reduces at high velocities to... 

Despite the fact that Bohr s stopping power theory is useful for heavy charged particles such as fission fragments, Rutherford s collision cross section on which it is based is not accurate unless both the incident particle velocity and that of the ejected electron are much greater than that of the atomic electrons. The quantum mechanical theory of Bethe, with energy and momentum transfers as kinematic variables, is based on the first Born approximation and certain other approximations [1,2]. This theory also requires high incident velocity. At relatively moderate velocities certain modifications, shell corrections, can be made to extend the validity of the approximation. Other corrections for relativistic effects and polarization screening (density effects) are easily made. Nevertheless, the Bethe-Born approximation... 

Roehrl MHA, Wang JV and Wagner G. Discovery of Small-Molecule Inhibitors of the NFAT-Calcineurin Interaction by Competitive High-Throughput Fluorescence Polarization Screening. Biochemistry 200, 43 16067-16075. 

Most of these diagrams contain two intermediate electron propagators and, therefore, double summations over the whole spectrum of the Dirac equation in the external nuclear field. This makes their computation numerically intensive. Both the selfenergy and vacuum-polarization screening corrections are ultraviolet divergent and require renormalization to yield a finite result. 

Charge Transfer and Polarization Screening at Organic/Metal Interfaces Single Crystalline Versus Polycrystalline Gold... 

Blue, brown or red zones in vis. In the polar screening system A, essential oils migrate unresolved at the solvent front. 

Clark, N. A. D. Coleman, and J. E. Maclennan. 2000. Electrostatics and the electro-optic behaviour of chiral smectics C Block polarization screening of applied voltage and V-shaped switching. Liq. Cryst. 27(7) 985-990. 

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