Ultra-small-angle X-ray scattering USAXS

The ultra small-angle X-ray scattering (USAXS) extends the accessible structure towards the micrometer range. Time-resolved measurements require a synchrotron beam that is intensified by an insertion device (Sect. 4.2.2). 

Ultra small-angle x-ray scattering (USAXS) is capable of determining all characteristics of agglomerate and primary particles from a single scattering experiment mass fractal dimension, Dj, radii of gyration (primary particles and... 

In the SAXS regime, typical nanostructures (e.g., domain sizes and long periods in semicrystalline materials, thermoplastic elastomers) are observed, while the ultra small angle X-ray scattering (USAXS) extends the accessible structure towards the micrometer range (e.g., spherulites). In addition to size and orientation of domains as determined by WAXS, the arrangement of crystalline domains within SMPs could be characterized by SAXS. The programming and recovery processes performed... 

Previous studies have shown that the ordered structure took cubic (bcc or fee) lattices with a lattice constant of 0.1-1 )im [1], Recently, an ultra-small-angle X-ray scattering (USAXS) method, by which an electron density fluctuation of several pm is detectable, has been developed and has made it possible to perform detailed studies on the ordered structure [3,4]. In the present paper, we report an USAXS study at several surface charge densities and salt concentrations. 

Fig. 2 Ultra-small-angle X-ray scattering (USAXS) profiles for aqueous dispersions of KE-PlOW silica at (a)cTs, = 0.1 x 10" Ccm and (b) 1.1 X 10" Ccm". C, = 10" M. Inset shows the phase diagram for KE-PlOW...

Schaefer and Justice [28] suggest an additional parameter that would be missed by WAXS and TEM. They suggest that large-scale particle-particle associations and particle randomization of fully exfoliated polymer-montmorillonite nanocomposites compromise the ultimate mechanical performance. For fully exfoliated nanocomposites, ultra-small-angle X-ray scattering (USAXS) is needed to identify the presence of large-scale particle associations. 

The ultra small-angle X-ray scattering (USAXS) extends the accessible stmcture towards the micrometer range [59]. 

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