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Electrons delta electron

Vgiec and Vxc represent the electron-nuclei, electron-electron and exchange-correlation dionals, respectively. The delta function is zero unless G = G, in which case it has lue of 1. There are two potential problems with the practical use of this equation for a croscopic lattice. First, the summation over G (a Fourier series) is in theory over an rite number of reciprocal lattice vectors. In addition, for a macroscropic lattice there effectively an infinite number of k points within the first Brillouin zone. Fortunately, e are practical solutions to both of these problems. [Pg.174]

Delta Ray—Electron removed from an atom during the process of ionization (also called secondary electron). Delta rays cause a track of ionizations along their path. [Pg.273]

A heavy charged particle can knock out an electron from a molecule with maximum energy Emax —2/ra>2 (at v>v0), whereas for a fast electron with the same velocity the knocked out electron has max — mu2/2. Consequently, while an electron can knock out electrons with velocity no greater than its own, a heavy particle, in head-on collisions, produces delta electrons with velocities which can be twice as high as that of the ion. As a result, the energy of such delta electrons can be distributed to the regions of the medium far more remote from the point of initial ionization than in the case of electron irradiation. [Pg.360]

For each parameter of the track the top number corresponds to the alpha particle and the bottom number-to the multicharged ion 127I. N, and Ns are, respectively, the number of ions and the number of delta electrons the particle produces per 1 nm of its path length n] is the average concentration of ions in the core of the track n, is the average concentration of ions in the track and rsh is the radius of the track shell. [Pg.363]

As a proton slows down, its LET, as well as the number of delta electrons, increase, while the size of the track, on the contrary, becomes smaller since the maximum energy of delta electrons lowers. As a result, one observers a sharp increase both of the local concentrations near the track s axis and of average concentrations. This favors the increase of yields of products of recombination of active particles with increase of LET, that is, there is a direct correspondence between the density of active particles in the track and the LET. A similar picture is observed in tracks of alpha particles. [Pg.368]

Effective charge Average number of delta electrons ejected over 1 nm 0.69 2 0.93 2... [Pg.369]

The radiation effect produced by heavy ions can be simulated with electrons if the ions have high velocities. It is in this case that the spatial distribution of active particles in the track is close to the one in tracks of fast electrons. At small velocities of heavy ions the tracks of delta electrons overlap each other to a considerable extent, which results in the concentration of charged particles in a microvolume of the ion s track being very high. With development of powerful pulsed electron accelerators it became possible to create high concentrations of active particles in a medium. According to Ref. 372, with such accelerators one is able to reproduce and study the processes occurring in tracks of heavy ions. [Pg.373]

Other applications for this technology include a green P-OLED display for the control and indication of all the system operations on a personal MP3 music player produced by the US Delta Electronics company. CDT s MicroEmissive Displays licensee has developed a P-OLED display for the amazing NHJ 3-in-l camera which combines MP3 player, still and movie cameras into a single 3.2 million pixel product which incorporates a USB connection. [Pg.68]

DELTA Electronic, Szientendrei lit 39, Budapest Warlha Vince utca 1. N 30. H-8201 Veszprem,... [Pg.520]

The Delta Electronics RG-1 and RG-3 receiver generator sets are specifically designed for such use. There is over 120 dB of isolation between the generator and receiver portions and double shielded coaxial cables are provided with the units for connection to the OIB-3. [Pg.9]

The symbol M represents the masses of the nuclei in the molecule, which for simplicity are taken to be equal. The symbol is the Kionecker delta. The tensor notation is used in this section and the summation convention is assumed for all repeated indexes not placed in parentheses. In Eq. (91) the NACT appears (this being a matrix in the electronic Hilbert space, whose components are denoted by labels k, m, and a vector with respect to the b component of the nuclear coordinate R). It is given by an integral over the electron coordinates... [Pg.145]


See other pages where Electrons delta electron is mentioned: [Pg.947]    [Pg.95]    [Pg.98]    [Pg.100]    [Pg.104]    [Pg.362]    [Pg.363]    [Pg.363]    [Pg.367]    [Pg.368]    [Pg.369]    [Pg.369]    [Pg.369]    [Pg.58]    [Pg.1013]    [Pg.2]    [Pg.3]    [Pg.8]    [Pg.22]    [Pg.540]    [Pg.2213]    [Pg.268]    [Pg.172]    [Pg.687]    [Pg.491]    [Pg.403]    [Pg.746]    [Pg.65]   
See also in sourсe #XX -- [ Pg.362 ]




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