Bragg geometry

In the reflection geometry (or in analogy, the Bragg geometry), the cell window is parallel to the electrolyte surface. The current distribution and iR-dvop is... 

Fig. 6.7. Schematic cell designs for X-ray scattering experiments (a) reflection (Bragg) geometry (b) transmission (Laue) geometry...

In a previous paper (De Chiara and Prontera, 1992) we derived the expression of the reflectivity of a mosaic crystal in Bragg geometry in the general case of linearly polarized X-rays and we discussed the optimization criteria of the hard X-ray reflectivity of mosaic crystals. 

Toney MF, Brennan S (1989) Observation of the effect of refraction on x-rays diffracted in a grazing-incidence asymmetric Bragg geometry. Phys Rev B 39 7963-7966 Wemple SH, DiDomenico M Jr (1969) Optical dispersion and the structure of solids. Phys... 

Figure 4 Diffraction patterns (Bragg-Brentano geometry) of three superconducting thin Aims ( 2- im thick) anneaied for different times. The temperatures for 0 resistance and for the onset of superconductivity are noted.

The use of Equation (22) is very general, but it is also possible, with accurate measurements and data treatment, to perform the quantitative phase analysis in semi-crystalline materials without using any internal standard. This procedure is possible only if the chemical compositions of all the phases, including the amorphous one, are known. If the composition of the amorphous phase is unknown, the quantitative analysis without using any internal standard can still be used provided that the chemical composition of the whole sample is available [51]. This approach, until now, has been developed only for the XRD with Bragg-Brentano geometry that is one of the most diffused techniques in powder diffraction laboratories. 

An expression including the diffuse background of a crystalline phase was calculated for a Bragg-Brentano geometry [55] ... 

Fig. 68 Comparison of temperature-dependent intensity of first-order Bragg peak for bare matrix copolymer (A) containing 0.5 wt% nanocomposites with plate-like (V), spherical (o) and rod-like ( ) geometry. Data are vertically shifted for clarity. Inset dependence of ODT temperature on dimensionality of fillers (spherical 0, rod-like 1, plate-like 2). Vertical bars width of phase transition region. Pure block copolymer is denoted matrix . From [215]. Copyright 2003 American Chemical Society...

Figure 12.3b shows the widths of the Bragg layers as a function of the layer number of the CBNL depicted in Fig. 12.3a. There are two notable properties of the Bragg layers (1) the width of the high-index layers is smaller than the width of the low-index layers, and (2) the width of the layers decreases exponentially as a function of the radius, converging asymptotically to a constant value. The first property exists in conventional DBRs as well and stems from the dependence of the spatial oscillation period, or the wavelength, on the index of refraction. The second property is unique to the cylindrical geometry and arises from the nonperiodic nature of the solutions of the wave equation (Bessel or Hankel functions) in this geometry.

Circular Bragg nanolasers (CBNLs) of several geometries and Bragg reflector orders were fabricated within a thin membrane of InGaAsP semiconductor material21. A cross-section of the semiconductor epitaxial structure used is illustrated... 

Figure 5.7 Derivation of Bragg s law of X-ray diffraction. Parallel X-rays strike the surface at an angle 0, and are reflected from successive planes of crystals of interplanar spacing d. The path difference between reflections from successive planes is given by AB + BC, which, by geometry, is equal to 2dsin0. For constructive interference, this must be equal to a whole number of wavelengths of the incoming radiation.

Figure 2.6 Si 220 reflection, (a) duMond diagram showing the wavelength-angle coupling imposed by the Bragg law, (b) the corresponding real-space geometry...

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