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Four-current

The symbols in this equation are defined below). It was shown by Gordon [323], and further discussed by Pauli [104] that, by a handsome tr ick on the four current, this can be broken up into two parts J" = djgj (each divergence-free),... [Pg.159]

As noted above, jC in Eq. (154) arises from terras in which p 7 v. The corresponding contribution to the four current was evaluated in [104,323] and was shown to yield the polarization cuirent. Our result is written in teims of the magnetic field H and the electric field E, as well as the spinor four-vector v / and the vectorial 2x2 sigma raatiices given in Eq. (151). [Pg.165]

There are four current loops inside of every switching power supply. Each of these loops must be kept separate from one another. They are listed in order of their importance to a good PCB layout. [Pg.93]

Structural changes on surfaces can often be treated as first-order phase transitions rather than as adsorption process. Nucleation and growth of the new phase are reflected in current transients as well as dynamic STM studies. Nucleation-and-growth leads to so-called rising transients whereas mere adsorption usually results in a monotonously falling transient. In Fig. 10 are shown the current responses to potential steps across all four current peaks in the cyclic voltammogram of Fig. 8a [44], With the exception of peak A, all structural transitions yield rising current transients sug-... [Pg.118]

In the relativistic version of DFT, the ground state energy of the system is a unique functional of the fermion four-current density, / (/-) ... [Pg.138]

In this equation, A, is a given external four-potential and J (x) is the four-current density. As the treatment is for stationary states, the external four-potential and the fermion four-current are independent of time. [Pg.138]

It is important to notice that the Coulomb-like term (the third term in the equation) is written in terms of the four-current, and the exchange and correlation energy is given by... [Pg.139]

Solving this iterative process gives rise to a set of orbitals to construct the ground state four-current, J (x), including vacuum polarization corrections due to the external field as well as the field mediating the interaction between the electrons. As the charge density in the nonrelativistic case, the four-current has the form of a reference noninteracting A-electron system,... [Pg.140]

The summation starts in -me2, and the energy in the current units is just m. To simplify the iterative process, a standard approximation neglects the vacuum polarization effects giving a simpler structure of the four-current [5,7] ... [Pg.140]

The SP-DFT has been shown to be useful in the better understanding of chemical reactivity, however there is still work to be done. The usefulness of the reactivity indexes in the p-, p representation has not been received much attention but it is worth to explore them in more detail. Along this line, the new experiments where it is able to separate spin-up and spin-down electrons may be an open field in the applications of the theory with this variable set. Another issue to develop in this context is to define response functions of the system associated to first and second derivatives of the energy functional defined by Equation 10.1. But the challenge in this case would be to find the physical meaning of such quantities rather than build the mathematical framework because this is due to the linear dependence on the four-current and external potential. [Pg.151]

Consequently, 0) may be understood as a functional [/ ]> of the ground state four current. As an immediate result, y/ also determines all ground state expectation values, in particular the ground state energy E = [/ ]. [Pg.229]

Moreover, assuming noninteracting u-representability [2], is chosen so, that for all g < 1 the corresponding ground state 0(g)> yields the exact interacting ground state four current... [Pg.238]

Besides the nuclear attraction, fextix) could also include additional external fields, if present. j/(x) denotes the fermion field operator of the interacting, inhomogeneous system characterized by if, p x ) is the corresponding fermion four current operator. [Pg.231]

LTC4 and LTD4 are potent bronchoconstrictors and are recognized as the primary components of the slow-reacting substance of anaphylaxis (SRS-A) that is secreted in asthma and anaphylaxis. There are four current approaches to antileukotriene drug development 5-LOX enzyme inhibitors, leukotriene-receptor antagonists, inhibitors of FLAP, and phospholipase A2 inhibitors. [Pg.400]

As pointed out by Sarfath [77], the basic form (7) of the four-current is related to the result of anholonomic electrodynamics. [Pg.62]

Let us consider a semiconductor electrode, at which a redox reaction of type (1) occurs. Electrons of both the conduction band and valence band may take part in the electrode process. As a result, the reversible reaction considered is characterized by four different types of electron transitions (see Fig. 6a). Transitions in which electrons leave the semiconductor and holes come in contribute to the cathodic current, and those where electrons come in and holes escape contribute to the anodic current. Thus, the resultant current is a sum of four currents i p, i >p (when referring to currents we shall always mean current densities). [Pg.271]

To summarize, there are four current methods for predicting KPA(25°C) the linear KOA method (Equation (3)), the Trapp method (Equation (4)), the Riederer method (Equation (5))... [Pg.139]

We have four current approximations (ri). Each one is given as a linear... [Pg.283]

Fig. 3.2 The four currently marketed racemic proton-pump inhibitors (PPIs). Fig. 3.2 The four currently marketed racemic proton-pump inhibitors (PPIs).
FIGURE 5-5 Unit cost estimates for four current and four possible future electrolysis technologies for the generation of hydrogen. See Table 5-2 and discussion in text. NOTE O M = operation and maintenance. [Pg.71]

Moreover, both the Lagrangian and the electronic four current have been written in a charge conjugation invariant form [27], i.e. under the charge conjugation (transforming electrons into positrons and vice versa) the four... [Pg.6]

In summary, one finds that there exists a one-to-one correspondence between the class of external potentials just differing by gauge transformations, the associated class of ground states and the ground state four current,... [Pg.15]


See other pages where Four-current is mentioned: [Pg.159]    [Pg.339]    [Pg.263]    [Pg.139]    [Pg.229]    [Pg.229]    [Pg.231]    [Pg.232]    [Pg.233]    [Pg.229]    [Pg.229]    [Pg.232]    [Pg.233]    [Pg.13]    [Pg.439]    [Pg.14]    [Pg.5]    [Pg.3]    [Pg.6]    [Pg.6]    [Pg.11]    [Pg.12]    [Pg.14]    [Pg.14]   
See also in sourсe #XX -- [ Pg.126 ]

See also in sourсe #XX -- [ Pg.601 ]




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