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Kinematic operator

The symbol V(q,Q) stands for a kinematic operator containing spin-orbit terms, electron-phonon couplings and, eventually, a coupling to external fields. The molecular Hamiltonian is given by ... [Pg.181]

For the electro-nuclear model, it is the charge the only homogeneous element between electron and nuclear states. The electronic part corresponds to fermion states, each one represented by a 2-spinor and a space part. Thus, it has always been natural to use the Coulomb Hamiltonian Hc(q,Q) as an entity to work with. The operator includes the electronic kinetic energy (Ke) and all electrostatic interaction operators (Vee + VeN + Vnn)- In fact this is a key operator for describing molecular physics events [1-3]. Let us consider the electronic space problem first exact solutions exist for this problem the wavefunctions are defined as /(q) do not mix up these functions with the previous electro-nuclear wavefunctions. At this level. He and S (total electronic spin operator) commute the spin operator appears in the kinematic operator V and H commute with the total angular momentum J=L+S in the I-ffame L is the total orbital angular momentum, the system is referred to a unique origin. [Pg.182]

K is a kinematic operator that damps the high momentum part of the wave function while keeps the low momentum part intact. Its appearance makes the DK-SOC operator bounded from below and variationally stable and a much better SOC operator than the BP-SOC. The effect of the K operator is illustrated by Fig. 8.7, where the 6p orbitals of Tl, At, and Rn are taken as examples. While the radial distribution function of the original Tl 6p orbital (Tl 6p) and the one after the operator of K (Tl K6p) are highly similar in Fig. 8.7a, the squares of these functions... [Pg.227]

Depending on the explicit reference to a subvariety or not and on the capacitive or inductive nature of the transferred entities, four models are distinguished. The transfer of basic quantities is modeled either by a reduced conductance (i.e., conductivity), linking an effort field (or lineic density) to a flow density, or by a composition of reduced capacitance and transfer (kinetic) operator (Graph 10.35a and c). The transfer of impulses uses either a reduced resistance (i.e., resistivity), linking the flow lineic density to the effort density, or a composition of reduced inductance and transfer (kinematic) operator (Graph 10.35b and d). [Pg.493]

N, Kinematic operator (impulse transfer) (global) [variety qr]... [Pg.750]

The heavy fuel should be heated systematically before use to improve its operation and atomization in the burner. The change in kinematic viscosity with temperature is indispensable information for calculating pressure drop and setting tbe preheating temperature. Table 5.20 gives examples of viscosity required for burners as a function of their technical design. [Pg.236]

Gla.ss Ca.pilla.ry Viscometers. The glass capillary viscometer is widely used to measure the viscosity of Newtonian fluids. The driving force is usually the hydrostatic head of the test Hquid. Kinematic viscosity is measured directly, and most of the viscometers are limited to low viscosity fluids, ca 0.4—16,000 mm /s. However, external pressure can be appHed to many glass viscometers to increase the range of measurement and enable the study of non-Newtonian behavior. Glass capillary viscometers are low shear stress instmments 1—15 Pa or 10—150 dyn/cm if operated by gravity only. The rate of shear can be as high as 20,000 based on a 200—800 s efflux time. [Pg.180]

Equations (22-86) and (22-89) are the turbulent- and laminar-flow flux equations for the pressure-independent portion of the ultrafiltra-tion operating curve. They assume complete retention of solute. Appropriate values of diffusivity and kinematic viscosity are rarely known, so an a priori solution of the equations isn t usually possible. Interpolation, extrapolation, even precuction of an operating cui ve may be done from limited data. For turbulent flow over an unfouled membrane of a solution containing no particulates, the exponent on Q is usually 0.8. Fouhng reduces the exponent and particulates can increase the exponent to a value as high as 2. These equations also apply to some cases of reverse osmosis and microfiltration. In the former, the constancy of may not be assumed, and in the latter, D is usually enhanced very significantly by the action of materials not in true solution. [Pg.2040]

The vanishing of this matrix element is, in fact, independent of the assumption of current conservation, and can be proved using the transformation properties of the current operator and one-partic e states under space and time inversion, together with the hermiticity of jn(0). By actually generating the states q,<>, from the states in which the particle is at rest, by a Lorentz transformation along the 3 axis, and the use of the transformation properties of the current operator, essentially the entire kinematical structure of the matrix element of on q, can be obtained.15 We shall, however, not do so here. Bather, we note that the right-hand side of Eq. (11-529) implies that... [Pg.713]

Previous theoretical kinetic treatments of the formation of secondary, tertiary and higher order ions in the ionization chamber of a conventional mass spectrometer operating at high pressure, have used either a steady state treatment (2, 24) or an ion-beam approach (43). These theories are essentially phenomenological, and they make no clear assumptions about the nature of the reactive collision. The model outlined below is a microscopic one, making definite assumptions about the kinematics of the reactive collision. If the rate constants of the reactions are fixed, the nature of these assumptions definitely affects the amount of reaction occurring. [Pg.146]

According to the Fraunhofer approximation of kinematic scattering theory the real space and the reciprocal space are related to each other by an integral transform known by the name Fourier transform, which shall be indicated by the operator The n-dimensional (nD) Fourier transform of h (r) is defined by... [Pg.31]

In the scattering operator Tr(z), all kinematical insertions contained in Hr are summed up in the external lines (see (Antonelli et al, 2001) for details). We calculate the matrix element of the scattering operator Tr(z) between the ir d states at 0(a). After removing the CM momentum, the spin-nonflip part of this matrix element on energy shell is equal to... [Pg.321]

A vessel 2 cm in diameter with "closed ends" is operated at a linear velocity of 5.2 cm/sec. Kinematic viscosity of the fluid is 0.0018 sgcm/sec. A... [Pg.640]

Irrespective of the approach taken to scale-up, the scaling of unit operations and manufacturing processes requires a thorough appreciation of the principles of similarity. Process similarity is achieved between two processes when they accomplish the same process objectives by the same mechanisms and produce the same product to the required specifications. Johnstone and Thring (56) stress the importance of four types of similarity in effective process translation (1) geometric similarity (2) mechanical (static, kinematic, and dynamic) similarity (3) thermal similarity and (4)... [Pg.112]

Kinematic and geometric similarity in fluids ensures geometrically similar streamline boundary films and eddy systems. If forces of the same kind act upon corresponding particles at corresponding times, they are termed corresponding forces, and conditions for dynamic similarity are met. While the scale-up of power consumption by a unit operation or manufacturing process is a direct consequence of dynamic similarity, mass and heat transfer—direct functions of kinematic similarity—are only indirect functions of dynamic similarity. [Pg.114]


See other pages where Kinematic operator is mentioned: [Pg.185]    [Pg.194]    [Pg.549]    [Pg.1115]    [Pg.1304]    [Pg.219]    [Pg.245]    [Pg.247]    [Pg.431]    [Pg.491]    [Pg.750]    [Pg.185]    [Pg.194]    [Pg.549]    [Pg.1115]    [Pg.1304]    [Pg.219]    [Pg.245]    [Pg.247]    [Pg.431]    [Pg.491]    [Pg.750]    [Pg.911]    [Pg.1236]    [Pg.63]    [Pg.412]    [Pg.32]    [Pg.81]    [Pg.10]    [Pg.67]    [Pg.170]    [Pg.434]    [Pg.251]    [Pg.68]    [Pg.13]    [Pg.177]    [Pg.180]    [Pg.412]    [Pg.421]    [Pg.422]    [Pg.432]    [Pg.180]    [Pg.102]    [Pg.175]    [Pg.29]   
See also in sourсe #XX -- [ Pg.181 ]




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