Shape reconstruction

Ab-Initio Methods for Shape Reconstruction of Identical Particles. On... 

If mixtures and assemblies of different kinds of particles are studied, a shape reconstruction is no longer possible from a study of isotropic SAXS in solution [188],... 

Fig. 31 Main plot SANS intensity (I) versus momentum transfer (q = 0.049-0.419 A-1) for 9 x 10 4 M polyradical 50 in THF-d8 at 170K. The symbols and solid line correspond to the experimental data points and the numerical fit using GNOM/DAMMIN simulated annealing, respectively. Inset low-resolution particle shape reconstruction for 50 obtained from the GNOM/DAMMIN fit. Two side views (rotated by 90°), using both the DAMMIN spheres and the spherical harmonics-based envelopes, are shown.94 Reproduced with permission from Ref. 94. Copyright 2004 Am. Chem. Soc.

Savarese S (2005) Shape reconstruction from shadows and reflections. PhD Thesis, California Institute of Technology... 

Boissonnat JD (1988) Shape reconstruction from planar cross sections. Computer Vision, Graphics, and Image Processing 44 1-29... 

Shape reconstruction from three orthogonal direction... 

Bio-inspired sensor, Condition assessment Flexible strain gauge Sensing skin Sensor network Shape reconstruction Soft elastomeric capacitor Structural health monitoring... 

There are different ways to compute scattering by arbitrary particle shapes reconstructed from a number of measured data points. Next we present an example using compactly supported radial basis functions (CS-RBF) for scattered data points processing. For this application we used the software toolkit by Kojekine et al. [121] available from www.karlson.ru. The data points represent a cube shaped particle as depicted in Fig. 3.30 and a number of 378... 

By integration of the loeal slopes, we have reconstructed the micro-mirror surface. An example is shown in Fig.4, along the line indicated by an arrow on the slope map. The surface deformations do not exceed 1 nm along the studied profile. Although surface shapes vary from mirror to mirror, deformations in the nanometer range demonstrate the remarkable quality of this device. 

The cytoplasmic domains reconstructed from negatively stained [90] and from frozen-hydrated samples [91,177] have similar shapes. Both include the protruding lobe and the bridge region that links the Ca " -ATPase molecules into dimers. The intramembranous peptide domains of the two ATPase molecules which make up a dimer spread apart as they pass through the bilayer toward the luminal side of the membrane, establishing contacts with the Ca -ATPase molecules in the neighboring dimer chains. The lateral association of dimer chains into extended crystal lattice is... 

The shape and dimensions of the ATPase molecule (Fig. 4) determined by the three-dimensional reconstruction of two-dimensional Ca -ATPase crystals [88-91,156, 157] can be compared with the distances between fluorophores bound at specified... 

Figure 9. Phase reconstruction of image reported in Figure 6 using the reference of image reported in Figure 8. The phase map is shown in (a), which includes a laterally averaged line-scan of 15 pixels, (b) A surface map of the two particles shape is displayed. The surface plot has been heavily noise filtered through Gaussian smoothing to better display the particles shape.

In this chapter we will have a closer look at the methods of the reconstruction of the momentum densities and the occupation number densities for the case of CuAl alloys. An analogous reconstruction was successfully performed for LiMg alloys by Stutz etal. in 1995 [3], It was found that the shape of the Fermi surface changed and its included volume grew with Mg concentration. Finally the Fermi surface came into contact with the boundary of the first Brillouin zone in the [110] direction. Similar changes of the shape and the included volume of the Fermi surface can be expected for CuAl [4], although the higher atomic number of Cu compared to that of Li leads to problems with the reconstruction, which will be examined. 

Quite complex kinetic behavior has been identified on some surfaces. For instance, on Ir(100), the TPD data from NO-saturated surfaces display two N2 desorption peaks, one at 346 K from the decomposition of bridge-bonded NO, and a second at 475 K from the decomposition of atop-bonded NO molecules [13], Interestingly, the first feature is quite narrow, indicating an autocatalytic process for which the parallel formation of N20 appears to be the crucial step. An additional complication arises from the fact that this Ir(100) surface undergoes a (1x5) reconstruction, and that NO adsorbed on the metastable unreconstructed (lxl) phase leads to N2 desorption at lower temperatures. In another example, on the reconstructed hexagonal Pt(100) surface, when a mixed NO + CO adsorbed layer is heated, a so-called surface explosion is observed where the reaction products (N2, C02 and N20) desorb simultaneously in the form of sharp peaks with half-widths of only 7 to 20 K. The shape of the TPD spectra suggests again an autocatalytic mechanism [14],... 

An ESRI system can be built with small modifications of commercial spectrometers by, for example, gradient coils fixed on the poles of the spectrometer magnet, regulated direct current (DC) power supplies, and required computer connections [40,53,55]. Gradients can be applied in the three spatial dimensions, and a spectral dimension can be added by the method of stepped gradients. The spectral dimension is important when the spatial variation of ESR line shapes (as a function of sample depth) is of interest this situation will be described below, in the ESRI studies of heterophasic polymers. In most systems, the software for image reconstruction in ESRI experiments must be developed in-house. 

For any method of structure reconstruction by ab-initio methods additional assumptions must be made. The multipole expansion95 method of Harrison, Stuhr-mann, and Svergun ([86], Sect. 5.3 [101], Chap. 6) assumes homogeneous internal density. The shape of the scattering curve is fitted by varying the envelope of the particle. 

The results of the experimental estimation of rate constants for all these reactions prove that larger the volume V4 of TS, lower the rate constant and higher the activation energy for reconstruction of the shape of the cage to form an appropriate orientation of polymer segments around TS. An empirical linear correlation between AEot = RT ln(/ci//cs) and the volume Vu of TS was found [8] as follows ... 

The decrease in IT is caused by small shifts of atoms located in a layer of 3 to 5 atomic diameters near the interface. Such shifts can be clearly observed in monociystals (reconstruction and relaxation phenomena) [12], There are mechanisms based on the decrease of A at V = const with the decrease of dispersion A/V. The results of action of these mechanisms are change of particle and pore shape, decrease of the micropore amount and surface roughness, etc. during sintering, coalescence, etc. 

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