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Local frame

Solution. Using Eqs. 3.9, the fluxes of components A and B in a local crystal frame (local C -frame) can be written... [Pg.453]

The I-frame localizes a projected quantum state this frame is a classical physics element, whereas configuration base states x) define a rigged Hilbert space basis [1]. [Pg.53]

For a quantum state defined by Ck-+ltB = 1 with k = (Ground state) and all other amplitudes zero, one identifies cases of photon states that may or may not interact with the ground state. I-frame localizes the quantum state so that one takes this case to represent an impinging light field ... [Pg.99]

Jousse C, Bruhat A, Carraro V et al 2001 Inhibition of CHOP translation by a peptide encoded by an open reading frame localized in the chop 5 UTR. Nucleic Acids Res 29 4341-4351 Katayama S, Tomaru Y, Kasukawa T et al 2005 Antisense transcription in the mammalian transcriptome. Science 309 1564-1566... [Pg.33]

Si i = 1,2,3) are the distances PP R denotes the 3x3 rotation matrix which transforms from the global reference frame / robot platform Fi ,F2 ,F3 to the sensor frame / local camera platform. We outline now the algorithm by which we determine the coordinates x, y, z of the perspective centre as well as the orientation parameters which constitute the 3x3 rotation matrix... [Pg.379]

Here the ijk coordinate system represents the laboratory reference frame the primed coordinate system i j k corresponds to coordinates in the molecular system. The quantities Tj, are the matrices describing the coordinate transfomiation between the molecular and laboratory systems. In this relationship, we have neglected local-field effects and expressed the in a fomi equivalent to simnning the molecular response over all the molecules in a unit surface area (with surface density N. (For simplicity, we have omitted any contribution to not attributable to the dipolar response of the molecules. In many cases, however, it is important to measure and account for the background nonlinear response not arising from the dipolar contributions from the molecules of interest.) In equation B 1.5.44, we allow for a distribution of molecular orientations and have denoted by () the corresponding ensemble average ... [Pg.1290]

Suppose that a gradient, G=G u is applied in the /-direction. In a local frame of reference rotating about the... [Pg.1522]

As before, we note that the resonance frequency of a nucleus at position r is directly proportional to the combined applied static and gradient fields at that location. In a gradient G=G u, orthogonal to the slice selection gradient, the nuclei precess (in the usual frame rotating at coq) at a frequency ciD=y The observed signal therefore contains a component at this frequency witli an amplitude proportional to the local spin density. The total signal is of the fomi... [Pg.1524]

Thii MNDO niijthod has 22 iiniqiiLi iwo-ctMUer two-eliicLron irUti-gials Ibr each pair ol heavy (non-hydrogen ) atoms in iheir local atomic frame. They are ... [Pg.286]

The PCM algorithm is as follows. First, the cavity siuface is determined from the van der Waals radii of the atoms. That fraction of each atom s van der Waals sphere which contributes to the cavity is then divided into a nmnber of small surface elements of calculable surface area. The simplest way to to this is to define a local polar coordinate frame at tlie centre of each atom s van der Waals sphere and to use fixed increments of AO and A(p to give rectangular surface elements (Figure 11.22). The surface can also be divided using tessellation methods [Paschual-Ahuir d al. 1987]. An initial value of the point charge for each surface element is then calculated from the electric field gradient due to the solute alone ... [Pg.612]

Two types of localized corrosion are pitting and crevice corrosion. Pitting corrosion occurs on exposed metal surfaces, whereas crevice corrosion occurs within occluded areas on the surfaces of metals such as the areas under rivets or gaskets, or beneath silt or dirt deposits. Crevice corrosion is usually associated with stagnant conditions within the crevices. A common example of pitting corrosion is evident on household storm window frames made from aluminum alloys. [Pg.274]

Plate-and-frame exchangers transfer heat by passing cooling fluids and process fluids between large corrugated panels. Crevices exist between closely spaced panels that stimulate localized attack. Plates... [Pg.4]

For a shock wave in a solid, the analogous picture is shown schematically in Fig. 2.6(a). Consider a compression wave on which there are two small compressional disturbances, one ahead of the other. The first wavelet moves with respect to its surroundings at the local sound speed of Aj, which depends on the pressure at that point. Since the medium through which it is propagating is moving with respect to stationary coordinates at a particle velocity Uj, the actual speed of the disturbance in the laboratory reference frame is Aj - -Ui- Similarly, the second disturbance advances at fl2 + 2- Thus the second wavelet overtakes the first, since both sound speed and particle velocity increase with pressure. Just as a shallow water wave steepens, so does the shock. Unlike the surf, a shock wave is not subject to gravitational instabilities, so there is no way for it to overturn. [Pg.18]

First of all, one needs to choose the local coordinate frame of a molecule and position it in space. Figure 2a shows the global coordinate frame xyz and the local frame x y z bound with the molecule. The origin of the local frame coincides with the first atom. Its three Cartesian coordinates are included in the whole set and are varied directly by integrators and minimizers, like any other independent variable. The angular orientation of the local frame is determined by a quaternion. The principles of application of quaternions in mechanics are beyond this book they are explained in detail in well-known standard texts... [Pg.119]

Mobile laboratories are another alternative. If large amounts of data need to be analyzed in a short time frame, having a lab on site can be a real asset. A local lab may also provide similar service. [Pg.61]

Under steady-state conditions, as in the Couette flow, the strain rate is constant over the reaction volume for a long period of time (several hours) and the system of Eq. (87) could be solved exactly with the matrix technique developed by Basedow et al. [153], Transient elongational flow, on the other hand, has two distinctive features, i.e. a short residence time (a few ps) and a non-uniform flow field, which must be incorporated into the kinetics equations. In transient elongational flow, each rate constant is a strongfunction of the strain-rate which varies with time in the Lagrangian frame moving with the center of mass of the macromolecule the local value of the strain rate for each spatial coordinate must be known before Eq. (87) can be solved. [Pg.140]

Consider the local interactions between d orbitals, referred to a local frame, and various bond orbitals. In Fig. A, we represent such interactions for orbitals characterizing local o... [Pg.138]

The measurement of the Lense-Thirring effect is the first scientific goal of the HYPER project (Fig. 3) and will be more detailed in this section. The Lense-Thirring effect consists of a precession of a local reference frame (realized by inertial gyroscopes) and a non-local one realized by pointing the direction of fixed stars. This Lense-Thirring precession is given by ... [Pg.364]

In studies of molecular dynamics, lasers of very short pulse lengths allow investigation by laser-induced fluorescence of chemical processes that occur in a picosecond time frame. This time period is much less than the lifetimes of any transient species that could last long enough to yield a measurable vibrational spectrum. Such measurements go beyond simple detection and characterization of transient species. They yield details never before available of the time behavior of species in fast reactions, such as temporal and spatial redistribution of initially localized energy in excited molecules. Laser-induced fluorescence characterizes the molecular species that have formed, their internal energy distributions, and their lifetimes. [Pg.259]

Temporal sequence of OH-LIF measurements captures a localized extinction event in a turbulent nonpremixed CH4/H2/N2 jet flame (Re 20,000) as a vortex perturbs the reaction zone. The time between frames is 125 ps. The velocity field from PIV measurements is superimposed on the second frame and has the mean vertical velocity of 9m/s subtracted. (From Hult, J. et al.. Paper No. 26-2, in 10th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon, 2000. With permission.)... [Pg.156]

When experimental results are later introduced, it will be seen that the significance of the final-state scattering in PECO measurements is confirmed by the observation that for C li core ionizations, which must therefore proceed from an initial orbital that is achiral by virtue of its localized spherical symmetry, there is no suggestion that the dichroism is attenuated. The sense of the chirality of the molecular frame in these cases can only come from final-state continuum electron scattering off the chiral potential. Generally then, the induced continuum phase shifts are expected to be of paramount importance in quantifying the observed dichroism. [Pg.281]

Similar convection-diffusion equations to the Navier-Stokes equation can be formulated for enthalpy or species concentration. In all of these formulations there is always a superposition of diffusive and convective transport of a field quantity, supplemented by source terms describing creation or destruction of the transported quantity. There are two fundamental assumptions on which the Navier-Stokes and other convection-diffusion equations are based. The first and most fundamental is the continuum hypothesis it is assumed that the fluid can be described by a scalar or vector field, such as density or velocity. In fact, the field quantities have to be regarded as local averages over a large number of particles contained in a volume element embracing the point of interest. The second hypothesis relates to the local statistical distribution of the particles in phase space the standard convection-diffusion equations rely on the assumption of local thermal equilibrium. For gas flow, this means that a Maxwell-Boltzmann distribution is assumed for the velocity of the particles in the frame-of-reference co-moving with the fluid. Especially the second assumption may break dovm when gas flow at high temperature or low pressure in micro channels is considered, as will be discussed below. [Pg.128]

The dynamic condition requires that the net force on any portion of the interface has to vanish. In a local coordinate frame attached to an interfacial position, three constraints are derived expressing the force balance for each of the three coordinate directions ... [Pg.231]


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See also in sourсe #XX -- [ Pg.53 , Pg.57 , Pg.58 , Pg.69 , Pg.79 , Pg.276 , Pg.278 , Pg.495 , Pg.497 , Pg.498 ]




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Center-of-mass Local Frame

Coordinate frame local

Local frame nonrotating

Local frame rotating

The Local Frame and Internal Energy

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