Scattering microbeam

This overview covers the major teclnhques used in materials analysis with MeV ion beams Rutherford backscattering, chaimelling, resonance scattering, forward recoil scattering, PIXE and microbeams. We have not covered nuclear reaction analysis (NRA), because it applies to special incident-ion-target-atom combinations and is a topic of its own [1, 2]. 

Beam collimation using a microaperture foil with a hole of 5 to 10 pm in diameter or a precisely manufactured slit is an easy method for the microbeam production [33,34]. The minimum beam spot size was limited to around 5 pm due to the size of the microaperture and contamination of particles scattered at the edge of the microaperture. 

In this chapter, we present in some detail gas adsorption techniques, by reviewing the adsorption theory and the analysis methods, and present examples of assessment of PSDs with different methods. Some examples will show the limitations of this technique. Moreover, we also focus on the use of SAXS technique for the characterization of porous solids, including examples of SAXS and microbeam small-angle x-ray scattering (pSAXS) applications to the characterization of activated carbon fibers (ACFs). We remark the importance of combining different techniques to get a complete characterization, especially when not accessible porosity exists. 

To show the suitability of microbeam pSAXS technique to characterize single carbon fibers, Figure 4.17 presents the two-dimensional scattering patterns corresponding to the center of each sample, after background and sample volume correction. These two-dimensional scattering patterns... 

Muller M, Czihak C, Vogl G, Fratzl P, Schober H, and Riekel C. Direct observation of microfibril arrangement in a single native cellulose fiber by microbeam small-angle x-ray scattering. Macromolecules, 1998 31 3953-3957. 

Muller M, Czihak C, Burghammer M, and Riekel C. Combined x-ray microbeam small-angle scattering and fibre diffraction experiments on single native cellulose fibres. J. Appl. Crystallogr., 2000 33 817-819. 

Lozano-Castello D, Raymundo-Pinero E, Cazorla-Amoros D, Linares-Solano A, Muller M, and Riekel C. Characterization of pore distribution in activated carbon fibers by microbeam small angle x-ray scattering. Carbon, 2002 40 2727-2735. 

Microbeam small angle X-ray scattering ( SAXS) a novel technique for the characterization of activated carbon fibers. 

G.44 Shuji Taira, ed. X-Ray Studies on Mechanical Behavior of Materials (Kyoto Society of Materials Science, Japan, 1974). A collaborative account by twenty-seven Japanese investigators of x-ray studies of phenomena affecting the strength of materials. X-ray stress measurements are described, as well as texture determination, line-broadening studies, microbeam methods, pseudo-Kossel patterns, small angle scattering, and x-ray topography. 

Lozano-CasteUo, D., Raymundo-Pinero, E., Cazorla-Amoros, D., et al. (2002). Microbeam small angle X-ray scattering (fJtSAXS) a novel technique for the characterization of activated carbon fibers. Stud. Surf. Sd. Catal., 144, 51—8. 

D.S. Bright, D.E. Newbury and R.B. Marinenko, Concentration-Concentration Histograms Scatter Diagrams Applied to Quantitative Compositional Maps, in Microbeam Analysis, (D.E. Newbury, Ed), San Francisco Press Inc., 1988. 

Recently, a microbeam smaU-angle scattering technique (p-SAXS) has been used for the fist time to characterize activated carbon fibers [51]. This made possible to study a single fiber rather than a bundle, and provided information on the evolution of porosity with the bum-off degree for different activating agents. 

It is possible to extract a microbeam from the vacuum system to use external beam measurement for specimens that cannot be placed in the vacuum, but the beam will suffer considerable scattering from the air or gas as well as from any exit foil. Nevertheless such an external microbeam can be very useful for low-resolution studies, for example in archaeology or biological sciences. 

Roth, S.V. et al. (2003). Fatigue behaviour of industrial polymers - a microbeam small-angle X-ray scattering investigation, J. Appl. Cryst. Vol.36 (2003), pp.684-688... 

Such lenses are cheaply constructed but suffer from the absorption and scattering. Many other techniques for the formation of intense X-ray microbeams are available on the basis of the use of various types of X-ray optics based on refraction, diffraction, or reflection bent mirrors, crystals and multi-layers, linear and tapered glass mono-capillaries, complex polycapillary lens systems, transmission Fresnel zone... 

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