Indent troughs

Let us consider one final example the application of atomic force microscopy (AFM) relating to nanoscale scratch and indentation tests on short carbon-fibre-reinforced PEEK/polytetrafluoroethylene (PTFE) composite blends (Han et al, 1999). In the scratch test, the tip was moved across the surface at constant velocity and fixed applied force to produce grooves with nanometre scale dimensions on the PEEK matrix surfaces. The grooves consisted of a central trough with pile-ups on each side. These grooves provide information about the deformation mechanisms and scratch resistance of the individual phases. In the nanoscale, indentation and... 

Meanwhile switch off gel apparatus and remove shark tooth comb. Clean the comb, and the trough formed in the gel with buffer to remove unpolymerized polyacrylamide. Re-insert the comb with teeth in first into the pre-formed trough, allowing teeth to touch the top surface of the gel causing a slight indentation. Do not allow teeth to pierce the gel. 

Figure 3.4. Indent on (001) of MgO crystal showing the troughs spreading along the T[100] and T[010] directions.

Fig. 16. Immuno-electrophoFetic separation of a normal human serum and sketch of the portions of resulting precipitation lines. The cross-hatched circle indicates the point of application for electrophoresis. Antibodies were applied in a trough-shaped indentation at the lower border.

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