Imaging of strain

Relaxation and spin-diffiision parameter imaging of strained polymers... 

One more application area is composite materials where one wants to investigate the 3D structure and/or reaction to external influences. Fig.3a shows a shadow image of a block of composite material. It consists of an epoxy matrix with glass fibers. The reconstructed cross-sections, shown in Fig.3b, clearly show the fiber displacement inside the matrix. The sample can be loaded in situ to investigate the reaction of matrix and fibers to external strain. Also absorption and transmission by liquids can be visualized directly in three-dimensions. This method has been applied to the study of oil absorption in plastic granules and water collection inside artificial plant grounds. 

Figure 8 shows the SEM images with a low level of strain (50%). It is clear that even with a low-strain level defects are initiated in the sulfur cured system with the formation of large cracks at the boundary layer between the two phases. However, in the peroxide cured system the mechanism of crack initiation is very different. In the latter case the NR-LDPE interface is not the site for crack initiation. In this case, stress due to externally applied strains is distributed throughout the matrix by formation of fine crazes. Furthermore, such crazes are developed in the continuous rubber matrix in a direction... 

Figure 3 2 Live cell epifluorescent images of tagged strains I, untagged cells (negative control) ii, Spc42-GFP tagged cells (positive control) andiii, Sui2-GFP tagged cells.

Figure 3-4 FRAP analysis of strain bearing Sui2-GFP PB, pre-bleached image B, bleached image R, recovered image. The bleached focus is marked with an arrow.

E. Konofagou and J. Ophir, A new elastographic method for estimation and imaging of lateral displacements, lateral strains, corrected axial strains and Poisson s ratios in tissues, Ultrasound Med. Biol., 1998, 24, 1183-1199. 

Fig. 20 Fluorescent images of prion deposits associated with distinct prion strains, murine chronic wasting disease (mCWD) (a) and murine sheep scrapie (mSS) (b), which has been stained by PTAA. (c) Correlation diagram of the ratios, R532/639 and R532/ max, of the intensity of the emitted light from PTAA bound to prion deposits originating from individual mice infected with CWD (black symbols) or sheep scrapie (purple symbols) [35]...

Figure 8.13 Experimental and simulated section topography images of hydrogen precipitates in silicon. All simulations were carried out using the same microscopic strain field, but the different position of the defects within the crystal results in substantially different image detail...

The past decade saw introduction of the low-energy electron microscope (LEEM) (12). It was expected potentially to be capable of moderately high resolution (6-mn) video-rate imaging of surfaces and interfaces. This would make it capable of studying dynamic processes at surfaces, thin-fibn growth, strain relief, etching, absorption. 

Figure 15.16 (a) TEM image of ligand-free PtRh nanowires extracted from RhPt wire/HMM-1 (b) high-resolution TEM image of a single strain of PtRh nanowire stabilized with PPhj ligand. 

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