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Borate Phosphor
Published in S. K. Omanwar, R. P. Sonekar, N. S. Bajaj, Borate Phosphors, 2022
Figure 2.7 depicts the geometry of small angle X-ray scattering. [It consist of an X-ray tube, detector and sample holder. It consist of an aerosol generator, switching module, pure gas system, inlet, inner flow tube X-ray source, conductive kapton windows and SAXS detector]. It makes glancing angle, diffraction angle and aperture. As the name suggests, scattering is not a diffraction method; small-angle scattering is used for low-order condensed matter materials, metals alloys, liquid crystals, porous materials, powders, ceramics, synthetic polymers in solution and in bulk and biological macromolecules in solution. This method provides structural information on particle size and size distributions, shape and orientation distributions. Moreover, it also provides the internal low-resolution molecular structure of biological systems [87].
Silica Fillers for Elastomer Reinforcement
Published in Anil K. Bhowmick, Current Topics in ELASTOMERS RESEARCH, 2008
Doug J. Kohls, Dale W. Schaefer, Raissa Kosso, Ephraim Feinblum
Particles are characterized by a variety of techniques to determine particle size, shape, and surface structure. Microscopy allows for a quick visualization of the particles and can give information on a broad range of sizes, from nanometer to millimeter particle diameters. Another approach to particle characterization uses the scattering of light, x-rays, and neutrons. Small-angle scattering is useful for examining intermediate sizes, nanometer–micrometer, of the particles and it is possible to probe the internal structure of the sample. Small-angle scattering techniques are well known and established for characterizing the morphology of micron and submicron polymeric and ceramic materials.15–24
Research Methods of Nanostructures and Nanomaterials
Published in Zulkhair A. Mansurov, Carbon Nanomaterials in Biomedicine and the Environment, 2020
Zulkhair A. Mansurov, Nina. N. Mofa, Tatyana A. Shabanova
Among other known methods of diffraction investigations, X-ray structural analysis is most widely spread. To study the non-homogeneous structure of nanometer sizes (nanoclusters, pores, molecular aggregates, colloids, nuclei of a new phase and so on), the method of small-angle scattering is mostly used. With the presence of atomic ordering it allows this method helps to reveal the structures with the period of tens of nanometers (Fig. 3.20).
Relation between dark-field images derived using X-Ray Talbot–Lau interferometer and carbon fiber distribution in CFRP
Published in Advanced Composite Materials, 2021
Yusuke Kasai, Akinori Yoshimura, Masahiro Arai, Keita Goto, Atsuhiko Yamanaka, Hiromichi Shindo
As described in this section, to evaluate the fiber arrangement and orientation by TLI, we propose a model that relates the TLI dark-field image to microstructures in CFRP. As explained above, the contrast of the TLI dark-field image differs depending on the relative angle between the gratings and sample. Presuming a sample in which fibers of several micrometers diameter are embedded (Figure 2), the direction of X-rays is along the axis. Fibers are oriented along y axis. In this case, the sample has micrometer-scale structures in the x direction. Then the strong small-angle scattering occurs to the x direction. However, little scattering occurs in the y direction because a similar structure continues along the y direction. When fibers are parallel to the gratings (Figure 2(a)), strong scattering is detected. By contrast, when fibers are perpendicular to the gratings (Figure 2(c)), almost no scattering is detected. In other words, scattering to the certain direction, which matches the direction of gratings, is extracted. Evaluation of fiber orientation is therefore possible by comparing TLI dark-field images taken for various relative angles between the sample and the gratings.
On the usage of a neutron source to determine the density distribution in compacted cemented carbide powder compounds
Published in Powder Metallurgy, 2018
Hjalmar Staf, Elias Forssbeck Nyrot, Per-Lennart Larsson
Equation (10) holds for a monochromatic radiation with no scattering or small angle scattering. For a polychromatic beam, used in these experiments, a filtering effect called ‘beam hardening’ occurs due to the different MAC of different neutron energies. This will result in deviations from Equation (10) and artefact gradients in the tomography where material in the middle of the sample will appear less dense compared to the material at the surface. By measuring the transmittance in the calibration rods this effect could be validated and corrected for. In Figure 3(a) a negative log image of the 5 mm thick calibration sample is shown, i.e. the grey value in this case equals αx (compare Equation (10)). In Figure 3(b) the grey value along the horizontal direction (in the yellow square indicated in Figure 3(a)) is shown. Since the thickness x is known, LAC can be calculated from the graph.
Multiscale modelling and splitting approaches for fluids composed of Coulomb-interacting particles
Published in Mathematical and Computer Modelling of Dynamical Systems, 2018
In the following, we consider different 3D experiments related to a particle model with collisions. The modelling is based on designing plasma reactors with low temperature plasma, see [29]. Such reactors are used for the deposition of thin films on a different material, see [27] and [30]. The kinetic phenomena are crucial and important for the design of such apparatus, see [13]. We concentrate on small-angle scattering, which dominates in Coulomb collisions. Here, realistic models are given with Argon plasma, where the simulations are important for controlling the relaxation in the particle interactions, see [86]. We concentrate on collisions between ions and ions, i.e. Ar–Ar, see [4].