Anisotropic scattering patterns

Peaks in Isotropic and Anisotropic Scattering Patterns 8.2.2.1 Isotropy and Anisotropy... 

Both for isotropic and anisotropic scattering patterns line profile analysis can be performed. If a curve from an anisotropic pattern is analyzed, the results are limited... 

We notice that anisotropic scattering patterns can be calibrated to absolute intensity, as well. 

For anisotropic scattering patterns and the multidimensional case Vonk ( [168] and [22], p. 302) has proposed to utilize a multidimensional correlation function. It is not frequently applied. 

Tchoubar. For the application to anisotropic scattering patterns Stribeck [26] has extended this principle to a space of deliberate dimensionality. Available technology constricts its practical use to the scattering of materials with fiber symmetry, and the fiber-symmetrical CDF... 

Very recently an anisotropic scattering pattern from photo-excited myoglobin was observed, including its temporal change from 100 ps to 1 ps [37]. The relatively slow rotational motion of myoglobin made this observation possible with the 100 ps time resolution available at a synchrotron source. 

Figure 5. Schematic diagram of a SANS experiment on a side group liquid crystal polymer with the mesogenic units aligned by the magnetic field B. Some of the backbones are deuterium labeled so that the area detector measures an anisotropic scattering pattern which is used to determine the dimensions of the backbones.

Fatigue test at a synchrotron. Presently the minimum X-ray exposure required to record good anisotropic scattering patterns is still too long to monitor practical fatigue tests. With advanced technique and respective synchrotron beamlines this will become possible in the future. Nevertheless, as we have tried to demonstrate, even slow load-cycling experiments can shed some light on the mechanisms of structure response of polymeric composites under dynamic load. 

Interpretation of Anisotropic 2D Scattering Pattern Polymer crystallization under external fields (e.g., shear or extensional flows, stretching of polymer solids) usually exhibits preferred orientation, which results in anisotropic scattering patterns. For example, a four-point SAXS pattern was seen during solid-state uniaxial deformation of an ethylene-propylene copolymer (both experimental data and fitted 3D plot are shown in Fig. 1.17) [108]. 

SANS provides a unique tool to explore stmctural details of polymeric systems and allows kinetic studies with a resolution of a few seconds or less. Phenomena observed in polymer blends allow molecular interactions to be assessed as well as proof of theoretical predictions of static and kinetic properties of, respectively, critical phenomena and phase transition (Sections 2.11.3.2 and 2.11.3.3). Quenched SANS allows the evolution of anisotropic scattering patterns after application of sudden strain thereby extending the effeaive time window for the observation of polymer relaxation and their hierarchy in systems with more complicated architeaures from spin echo toward macroscopic times using time-temperature scaling (Section 2.11.3.4). 

Hrese shear-enhanced concentration fluauations give rise to strong scattered intensity along the x-axis but not much along the z-axis, giving rise to the butterfly-type anisotropic scattering pattern as shown in Figure 15(d) and the contrast... 

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