Voids, void scattering

Dispersed discontinuities Occur in A1 and Mg alloy castings. Appear as tiny voids scattered in parts or throughout the castings. Gas porosity and shrinkage porosity in A1 alloys are examples of this flaw... 

Fig. 30. A simultaneous saxs/waxs experiment on an oriented sample which requires both area detectors for the saxs and waxs region. An HDPE sample is stretched. The deformation induces a martensitic phase transformation as evidenced by the occurrence of extra reflections in the waxs region (top row of diagrams, see arrow). Void scattering is found in the saxs patterns (bottom row of diagrams). For a further explanation one is referred to the text and to References 122 and 123.

The following brief account is concerned with factors that affect the acces-sibihty of the OH groups of cellulose, since this is the determining factor for its dissolution, hence subsequent derivatization. Electron microscopy. X-ray scattering and porosimetry of cellulose fibers have clearly shown the presence of non-uniform pores, capillaries, voids and interstices in the fiber surface [25]. Consequently, the total surface area of cellulose fibers exceeds by far the geometrical outer surface. Pore structure determines the internal... 

Let us consider a frequent problem the scattering of elongated voids or of mi-crofibrils is investigated. In such materials an equatorial streak is observed - similar to the one sketched in Fig. 9.6. If the voids were perfectly oriented, its integral breadth measured as a function of s 2... 

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