X-ray analysis, small angle

Table VII. Comparison of Small Angle X-Ray Analysis of PMMA-g-PSX Copolymers with TEM Domain Size Data (Copolymers 16 wt.% PSX)...

Small angle X-ray analysis Oligomer size and shape. 

Figure 10-13. The melting temperature dependence of the reciprocal lamellar thickness Ijd of lamellae for poly(trifluorochloroethylene). The lamellar thickness was measured as the inter-lamellar distance by small-angle X-ray analysis, and thus contains both the crystalline component and the amorphous surface layer (after J. D. Hoffman from data of P. H. Geil and J. J. Weeks).

The crystal-liquid crystal phase transition behavior and the membrane structure in the artificial amphiphile/ water system were investigated on the basis of the thermal analysis, and wide- and small-angle x-ray analysis. 

Another informative method of nanocomposites characterization is the wide angle X-ray structural analysis (WAXS) and especially small-angle X-ray analysis (SAXS). X-ray analysis allows one to determine the lattice parameters of nanoparticles and, as it was found [2, 12] for the majority of suliides and oxides, the small particles exhibit the same lattice parameters and crystallographic structure as bulk substances up to the size of 20 A. At this size, the deformation of the lattice takes place which accompanies the transition to cluster structure with minimized full energy, induding free energy of the surface [11]. 

Semiconductor chemical sensors 101 ShJdovsky-Epfros approach 106 Simulation, Monte Carlo 107 Small angle X-ray analysis 85 Superferromagnetism 118 Superlattice 82 Supeiparamagnetism 118 Surface plasmon 99... 

Schurz J, Janosi A, Wrentschur E, KrSssig H and Schmidt H (1982) A small-angle X-ray analysis of polyacrylonitrile (PAN) fibers, Colloid Polym Sci 260 205-211. 

Section 2 of this chapter describes the characterization of carbonaceous materials by powder X-ray diffraction, small-angle-X-ray scattering (SAXS), measurements of surface area, and by the carbon-hydrogen-nitrogen (CHN) test, a chemical analysis of composition. In this section, we also describe the electrochemical methods used to study carbonaceous materials. 

Using IR spectroscopy and NMR, one can analyze the chemical structure of PA. The molecular weight and molecular weight distribution can be analyzed by endgroup analysis, viscometry, and high-pressure liquid chromatography (HPLC). The crystalline order can be analyzed by WAXS, small-angle X-ray spectroscopy... 

Characterization of the samples by TGA and CHN analysis shows that the template was effectively removed (C < 0.2 wt%). Small-angle X-ray scattering data of the calcined solid shows a reduction in the unit cell due to thermal shrinkage, while the values for the Fenton samples coincide with the starting precursor. Our approach therefore completely preserves the unit cell corresponding to the diameter of the micelles contained in the mesophase. 

Dingenouts, N., Bolze, J., Potschke, D., Ballauf M. Analysis of Polymer Latexes by Small-Angle X-Ray Scattering. VoL 144, pp. 1-48... 

See, for example, Feigin L. A. and Svergun D. I., Structure Analysis by Small-Angle X-ray and Neutron Scattering, Plenum Press, New York, 1987. 

The thickness of the ordered crystalline regions, termed crystallite or lamellar thickness (Lc), is an important parameter for correlations with thermodynamic and physical properties. Lc and the distribution of lamellar thicknesses can be determined by different experimental methods, including thin-section TEM mentioned earlier, atomic force microscopy, small-angle X-ray scattering and analysis of the LAM in Raman spectroscopy. 

Options of data analysis can be deduced from the magic square and our notions concerning the structure. As an example let us consider the case of small-angle X-ray scattering. Here it is, in general, assumed that the structure is described by a continuous density function. Although there is no9 way back from intensity to density, there are several options for data analysis ... 

Stribeck N (1980) Computation of the Lamellar Nanostructure of Polymers by Computation and Analysis of the Interface Distribution Function from the Small-Angle X-ray Scattering. Ph.D. thesis, Phys. Chem. Dept., University of Marburg, Germany... 

T.J. Wess, M. Drakopoulos, A. Snigirev, J. Wounters, O. Paris, P. Fratzl, M. Collins, J. Hiller, K. Nielsen, The Use of Small Angle X Ray Diffraction Studies for the Analysis of Structural Features in Archaeological Samples, Archaeometry, 43, 117 129 (2001). 

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