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Space contrast

A stress that is describable by a single scalar can be identified with a hydrostatic pressure, and this can perhaps be envisioned as the isotropic effect of the (frozen) medium on the globular-like contour of an entrapped protein. Of course, transduction of the strain at the protein surface via the complex network of chemical bonds of the protein 3-D structure will result in a local strain at the metal site that is not isotropic at all. In terms of the spin Hamiltonian the local strain is just another field (or operator) to be added to our small collection of main players, B, S, and I (section 5.1). We assign it the symbol T, and we note that in three-dimensional space, contrast to B, S, and I, which are each three-component vectors. T is a symmetrical tensor with six independent elements ... [Pg.162]

Fireworks consist of contrasts in light There are two kinds of contrast space contrast and time contrast, in colour and brilliancy. Accordingly we have four relationships in these contrasts ... [Pg.14]

Space contrast. Colour contrast is more important than brilliancy. This rule comes from the requirement to madce each colour clearly visible without being disturbed by the dazzle For example, when a weak blue light is placed near a strong red light, we cannot easily recognize the blue as it is overshadowed by the dazzle from the red which is more brilliant Accordingly it is the best to select colours in the same class in Table 1. Namely, if we use the blue in the S class as the petals, we should use the red in the same class S as pistils, i.e. p and m are used. This is to use the "same visibility effect" ... [Pg.14]

What is chosen, the same visibility effect or the relief effect, depends upon the artistic purpose when planning the space contrast In ordinary cases, we make an effort so that both effects are consistent with each other thus we use a cold colour (green or blue) as the background (petals) against a warm colour (red or yellow) as the objects (pistils), even when we use the stars in the same class of brilliancy, to get a good relief effect ... [Pg.15]

Low space contrast and high time contrast are the special feature of this flower. [Pg.18]

Fig.13 shows examples of full round double petalled flower. In this case the second petal asists the first (13.1), the pistil (13 2) or lies between the two (13.3) in space contrast ... [Pg.19]

If the nanotubes hexameric doughnuts retained their structural integrity on the aqueous surface, their presence would leave void spaces on the aqueous surface at the close-packed state, hi fact, this was observed and the phenomenon is illustrated schematically in Fig 8.17. The hexagons superimposed on the circles indicate the void spaces leading to larger-than-expected estimated areas. The presence of these void spaces contrasts with the surface behavior of other pyro-gallol[4]arenes studied. [Pg.252]

A novel optimization approach based on the Newton-Kantorovich iterative scheme applied to the Riccati equation describing the reflection from the inhomogeneous half-space was proposed recently [7]. The method works well with complicated highly contrasted dielectric profiles and retains stability with respect to the noise in the input data. However, this algorithm like others needs the measurement data to be given in a broad frequency band. In this work, the method is improved to be valid for the input data obtained in an essentially restricted frequency band, i.e. when both low and high frequency data are not available. This... [Pg.127]

Secondly, the linearized inverse problem is, as well as known, ill-posed because it involves the solution of a Fredholm integral equation of the first kind. The solution must be regularized to yield a stable and physically plausible solution. In this apphcation, the classical smoothness constraint on the solution [8], does not allow to recover the discontinuities of the original object function. In our case, we have considered notches at the smface of the half-space conductive media. So, notche shapes involve abrupt contours. This strong local correlation between pixels in each layer of the half conductive media suggests to represent the contrast function (the object function) by a piecewise continuous function. According to previous works that we have aheady presented [14], we 2584... [Pg.326]

Muns ENDOR mvolves observation of the stimulated echo intensity as a fimction of the frequency of an RE Ti-pulse applied between tlie second and third MW pulse. In contrast to the Davies ENDOR experiment, the Mims-ENDOR sequence does not require selective MW pulses. For a detailed description of the polarization transfer in a Mims-type experiment the reader is referred to the literature [43]. Just as with three-pulse ESEEM, blind spots can occur in ENDOR spectra measured using Muns method. To avoid the possibility of missing lines it is therefore essential to repeat the experiment with different values of the pulse spacing Detection of the echo intensity as a fimction of the RE frequency and x yields a real two-dimensional experiment. An FT of the x-domain will yield cross-peaks in the 2D-FT-ENDOR spectrum which correlate different ENDOR transitions belonging to the same nucleus. One advantage of Mims ENDOR over Davies ENDOR is its larger echo intensity because more spins due to the nonselective excitation are involved in the fomiation of the echo. [Pg.1581]

The LMTO method [58, 79] can be considered to be the linear version of the KKR teclmique. According to official LMTO historians, the method has now reached its third generation [79] the first starting with Andersen in 1975 [58], the second connnonly known as TB-LMTO. In the LMTO approach, the wavefimction is expanded in a basis of so-called muffin-tin orbitals. These orbitals are adapted to the potential by constmcting them from solutions of the radial Scln-ddinger equation so as to fomi a minimal basis set. Interstitial properties are represented by Hankel fiinctions, which means that, in contrast to the LAPW teclmique, the orbitals are localized in real space. The small basis set makes the method fast computationally, yet at the same time it restricts the accuracy. The localization of the basis fiinctions diminishes the quality of the description of the wavefimction in die interstitial region. [Pg.2213]

As shown above in Section UFA, the use of wavepacket dynamics to study non-adiabatic systems is a trivial extension of the methods described for adiabatic systems in Section H E. The equations of motion have the same form, but now there is a wavepacket for each electronic state. The motions of these packets are then coupled by the non-adiabatic terms in the Hamiltonian operator matrix elements. In contrast, the methods in Section II that use trajectories in phase space to represent the time evolution of the nuclear wave function cannot be... [Pg.288]

The space filling model developed by Corey, Pauling, and Koltun is also known as the CPK model, or scale model [197], It shows the relative volume (size) of different elements or of different parts of a molecule (Figure 2-123d). The model is based on spheres that represent the "electron cloud . These atomic spheres can be determined from the van der Waals radii (see Section 2.10.1), which indicate the most stable distance between two atoms (non-bonded nuclei). Since the spheres are all drawn to the same scale, the relative size of the overlapping electron clouds of the atoms becomes evident. The connectivities between atoms, the bonds, are not visualized because they are located beneath the atom spheres and are not visible in a non-transparent display (see Section 2.10). In contrast to other models, the CPK model makes it possible to visualize a first impression of the extent of a molecule. [Pg.133]

This algorithm alternates between the electronic structure problem and the nuclear motion It turns out that to generate an accurate nuclear trajectory using this decoupled algoritlun th electrons must be fuUy relaxed to the ground state at each iteration, in contrast to Ihe Car-Pairinello approach, where some error is tolerated. This need for very accurate basis se coefficients means that the minimum in the space of the coefficients must be located ver accurately, which can be computationally very expensive. However, conjugate gradient rninimisation is found to be an effective way to find this minimum, especially if informatioi from previous steps is incorporated [Payne et cd. 1992]. This reduces the number of minimi sation steps required to locate accurately the best set of basis set coefficients. [Pg.635]


See other pages where Space contrast is mentioned: [Pg.25]    [Pg.392]    [Pg.15]    [Pg.15]    [Pg.347]    [Pg.431]    [Pg.25]    [Pg.392]    [Pg.15]    [Pg.15]    [Pg.347]    [Pg.431]    [Pg.444]    [Pg.446]    [Pg.507]    [Pg.8]    [Pg.97]    [Pg.779]    [Pg.1031]    [Pg.1531]    [Pg.1636]    [Pg.1647]    [Pg.1658]    [Pg.1659]    [Pg.2084]    [Pg.2220]    [Pg.2422]    [Pg.2803]    [Pg.274]    [Pg.108]    [Pg.243]    [Pg.160]    [Pg.164]    [Pg.168]    [Pg.426]    [Pg.601]   
See also in sourсe #XX -- [ Pg.14 ]




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