Use of a simple small-angle scattering device to determine particle-size distribution of thoria sols

1967 ◽  
Vol 39 (6) ◽  
pp. 628-632 ◽  
Author(s):  
William C. Stoecker
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Small Angle ◽  
Small Angle Scattering ◽  
Angle Scattering

Characterization of components of nano-energetics by small-angle scattering techniques

2007 ◽  
Vol 22 (7) ◽  
pp. 1907-1920 ◽  
Author(s):  
Joseph T. Mang ◽  
Rex P. Hjelm ◽  
Steven F. Son ◽  
Paul D. Peterson ◽  
Betty S. Jorgensen
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Small Angle ◽  
Particle Morphology ◽  
Small Angle Scattering ◽  
Nanoparticle Size ◽  
X Rays ◽  
Angle Scattering

Small-angle scattering (SAS) and ultra small-angle scattering techniques, employing x-rays and neutrons, were used to characterize six different aluminum nanopowders and nanopowders composed of molybdenum trioxide and tungsten trioxide nanoparticles. Each material has different primary particle morphology and aggregate and agglomerate geometry, and each is important to the development of nano-energetic materials. The combination of small-angle and ultra small-angle techniques allowed a wide range of length scales to be probed, providing a more complete characterization of the materials. For the aluminum-based materials, differences in the scattering of x-rays and neutrons from aluminum and aluminum oxide provided sensitivity to the metal core and metal oxide shell structure of the primary nanoparticles. Small-angle scattering was able to discriminate between particle size and shape and agglomerate and aggregate geometry, allowing analysis of both aspects of the structure. Using the results of these analyses and guided by scanning electron microscopy (SEM) images, physical models were developed, allowing for a quantitative determination of particle morphology, mean nanoparticle size, nanoparticle size distribution, surface layer thickness, and aggregate and agglomerate fractal dimension. Particle size distributions calculated using a maximum entropy algorithm or by assuming a log-normal particle size distribution function were comparable. Surface area and density determinations from the small-angle scattering measurements were comparable to those obtained from other, more commonly used analytical techniques: gas sorption using Brunauer–Emmett–Teller analysis, thermogravimetric analysis, and helium pycnometry. Particle size distribution functions derived from the SAS measurements agreed well with those obtained from SEM.

scholarly journals Small-angle scattering from polydisperse particles with a diffusive surface

2014 ◽  
Vol 47 (2) ◽  
pp. 642-653 ◽  
Author(s):  
Olexandr V. Tomchuk ◽  
Leonid A. Bulavin ◽  
Viktor L. Aksenov ◽  
Vasil M. Garamus ◽  
Oleksandr I. Ivankov ◽  
...  
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Power Law ◽  
Small Angle ◽  
Scattering Length ◽  
Small Angle Scattering ◽  
Scattering Data ◽  
Scattering Length Density ◽  
Angle Scattering

Particles with a diffusive surface, characterized by a deviation from the Porod power-law asymptotic behavior in small-angle scattering towards an exponent below −4, are considered with respect to the polydispersity problem. The case of low diffusivity is emphasized, which allows the description of the scattering length density distribution within spherically isotropic particles in terms of a continuous profile. This significantly simplifies the analysis of the particle-size distribution function, as well as the change in the scattering invariants under contrast variation. The effect of the solvent scattering contribution on the apparent exponent value in power-law-type scattering and related restrictions in the analysis of the scattering curves are discussed. The principal features and possibilities of the developed approach are illustrated in the treatment of experimental small-angle neutron scattering data from liquid dispersions of detonation nanodiamond. The obtained scattering length density profile of the particles fits well with a transition of the diamond states of carbon inside the crystallites to graphite-like states at the surface, and it is possible to combine the diffusive properties of the surface with the experimental shift of the mean scattering length density of the particles compared with that of pure diamond. The moments of the particle-size distribution are derived and analyzed in terms of the lognormal approximation.

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