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Orbit reconstruction

Expanded poly(tetrafluoro ethylene) (ePTFE) CORE-TEX W.L. Core Associates, Flagstaff, USA Regenerative membrane, osteoconductive membrane, large diameter aortic, and carotid vascular grafts, tension-free repair of ventral incisional hernia orbital reconstruction, facial reconstruction, rhinoplasty... [Pg.302]

Bittermann, G., Metzger, M.C., Schlager, S., Lagreze, W.A., Gross, N., Cornelius, C.P., Schmelzeisen, R., 2014. Orbital reconstruction prefabricated implants, data transfer, and revision surgery. Facial Plastic Surgery 30, 554—560. [Pg.99]

Khaliullin, G., van Veenendaal, M., and Keimer, B. (2007) Orbital reconstruction and covalent bonding at an oxide interface. Science, 318, 1114-1117. [Pg.165]

Using the theorem that the sufficiency condition for mathematical correctness in 3D-reconstruction is fulfilled if all planes intersecting the object have to intersect the source-trajectory at least in one point [8], it is possible to generalise Feldkamp s method. Using projection data measured after changing the sotuce-trajectory from circular to spiral focus orbit it is possible to reconstruct the sample volume in a better way with the Wang algorithm [9]. [Pg.494]

Another efficient and practical method for exact 3D-reconstruction is the Grangeat algorithm [11]. First the derivative of the three-dimensional Radon transfomi is computed from the Cone-Beam projections. Afterwards the 3D-Object is reconstructed from the derivative of the Radon transform. At present time this method is not available for spiral orbits, instead two perpendicular circular trajectories are suitable to meet the above sufficiency condition. [Pg.494]

H = di(Z—iy di are the potential parameters I is the orbital quantum number 3 characterizes the spin direction Z is the nuclear charge). Our experience has show / that such a model potential is convenient to use for calculating physical characteristics of metals with a well know electronic structure. In this case, by fitting the parameters di, one reconstructs the electron spectrum estimated ab initio with is used for further calculations. [Pg.142]

Diels-Alder reactions are allowed by orbital symmetry in the delocalization band and so expected to occur on the surface. In fact, [4-1-2] cycloaddition reaction occurs on the clean diamond (100)-2 x 1 surface, where the surface dimer acts as a dienophile. The surface product was found to be stable up to approximately 1,000 K [59, 60], 1,3-Butadiene attains high coverage as well as forms a thermally stable adlayer on reconstructed diamond (100)-2 x 1 surface due to its ability to undergo [4h-2] cycloaddition [61],... [Pg.37]

Instead, we believe the electronic structure changes are a collective effect of several distinct processes. For example, at surfaces the loss of the bulk symmetry will induce electronic states with different DOS compared to bulk. As the particle sizes are decreased, the contribution of these surface related states becomes more prominent. On the other hand, the decrease of the coordination number is expected to diminish the d-d and s-d hybridization and the crystal field splitting, therefore leading to narrowing of the valence d-band. At the same time, bond length contraction (i.e. a kind of reconstruction ), which was observed in small particles [89-92], should increase the overlap of the d-orbitals of the neighboring atoms, partially restoring the width of the d-band. [Pg.94]

Fig. 4.4.7 (a) Reconstruction of the Stationary Helical Vortex (SHV) mode from MRI data acquired with the spin-tagging spin-echo sequence [27], The axial flow is upwards and the inner cylinder is rotating clockwise. The two helices represent the counter-rotating vortex streamtubes. (b) Construction of Poincare map for SHV [41]. The orbit of a typical particle is... [Pg.427]

An approach to solving the inverse Fourier problem is to reconstruct a parametrized spin density based on axially symmetrical p orbitals (pz orbitals) centered on all the atoms of the molecule (wave function modeling). In the model which was actually used, the spin populations of corresponding atoms of A and B were constrained to be equal. The averaged populations thus refined are displayed in Table 2. Most of the spin density lies on the 01, N1 and N2 atoms. However, the agreement obtained between observed and calculated data (x2 = 2.1) indicates that this model is not completely satisfactory. [Pg.53]

Figure 2. [TCNE] [Bu,N].+ spin density obtained by MaxEnt reconstruction using an atomic orbital model, and subsequent projection onto the molecular plane of [TONE]-. Positive contour steps are 50 mpE/A- and negative contours are dashed (step 10mpB/A2). A significant off-centring is present. Figure 2. [TCNE] [Bu,N].+ spin density obtained by MaxEnt reconstruction using an atomic orbital model, and subsequent projection onto the molecular plane of [TONE]-. Positive contour steps are 50 mpE/A- and negative contours are dashed (step 10mpB/A2). A significant off-centring is present.
They found a whole bunch of soft phonons, which are primarily horizontally polarized, near the zone boundaries between M and X. The most unstable mode they observed is the Mj phonon, the displacement pattern of which is shown in Fig. 40 note the similarity between this pattern and the reconstruction model in Fig. 39. According to Wang and Weber, these soft phonons are caused by electron-phonon coupling between the surface phonon modes and the electronic 3 surface states at the Fermi surface. They attributed the predominant Ms phonon instability to an additional coupling between d(x — y ) and d(xy) orbitals of the Zj states. [Pg.268]

The line-integral expression (189), for the exchange-correlation potential of the HF-KS approach in Sect. 2.4, offers an interesting way to reconstruct the exchange potential for a given system, from the known HF solution for this system. Being alternative to schemes discussed in Sect. 3, this method provides an expression for the exchange potential solely in terms of the HF orbitals in the form... [Pg.93]

When we make these same comparisons for an internuclear separation of 20 bohr, we obtain the coefficients shown in Table 2.5 and the weights shown in Table 2.6. Now the orthogonalized AOs give the asymptotic ffinction with one configuration, while it requires three for the raw AOs. The energies are the same, of course. The EGSO weights imply the same situation. A little reflection will show that the three terms in the raw VB function are just those required to reconstruct the proper HI5 orbital. [Pg.42]

By inspecting Fig. 1.10, it is obvious that the most natural cleavage plane of a Si crystal is the (111) plane or its equivalent, namely, (iTl), (111), etc. Right after cleaving, on each of the surface Si atoms, there is a broken bond, or a dangling bond, that is perpendicular to the (111) surface. Each of the dangling bond orbitals is half filled, that is, has only one electron. The nascent Si(lll) surface is thus metallic and exhibits a threefold symmetry, as shown in Fig. 1.11 (a). However, because of the large number of unsaturated bonds, such a surface is unstable. It reconstructs even at room temperature, and loses its threefold symmetry. [Pg.13]


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See also in sourсe #XX -- [ Pg.527 ]




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