Pull-out technique

Single-screw A screw pulling-out technique was used Wilczynski et al. 2012a, b... 

F Hoecker, J Karger-Kocsis. Effects of matrix microstructure on the interfacial strength in GF/PP examined by a single fiber pull-out technique. Mekhanika Kom-pozitmykh Materialov 29 723-733, 1993. 

Another method developed at TRI for interfiber adhesion is a pull-out technique in which a fiber is displaced for a distance of 5 mm within a hair fiber bundle of well-defined packing density. The pull-out technique utilizes another attachment to the TRI/SCAN surface force analyzer. 

Another variation of the pull-out technique was reported by Hampe [41]. The main difference in his approach was in the geometry of the matrix material used to fabricate the test specimens. He used a small amount of polymer in the form of a hemisphere formed on the surface of a metal plate which in turn was mounted... 

The techniques described above have been used to demonstrate that failure can occur by (1) simple chain pull-out, (2) chain scission close to the interface, or (3) chain scission within one of the blocks (typically PS). The transition from chain pull-out to scission is essentially controlled by molecular weight whilst the location of the scission seems to depend on the entanglement density. Fig. 2 shows the transition between (2) and (3) as E is increased. 

The second procedure is different from the previous one in several aspects. First, the metallic substrate employed is Au, which does not show a remarkable dissolution under the experimental conditions chosen, so that no faradaic processes are involved at either the substrate or the tip. Second, the tip is polarized negatively with respect to the surface. Third, the potential bias between the tip and the substrate must be extremely small (e.g., -2 mV) otherwise, no nanocavity formation is observed. Fourth, the potential of the substrate must be in a region where reconstruction of the Au(lll) surface occurs. Thus, when the bias potential is stepped from a significant positive value (typically, 200 mV) to a small negative value and kept there for a period of several seconds, individual pits of about 40 nm result, with a depth of two to four atomic layers. According to the authors, this nanostructuring procedure is initiated by an important electronic (but not mechanical) contact between tip and substrate. As a consequence of this interaction, and stimulated by an enhanced local reconstruction of the surface, some Au atoms are mobilized from the Au surface to the tip, where they are adhered. When the tip is pulled out of the surface, a pit with a mound beside it is left on the surface. The formation of the connecting neck between the tip and surface is similar to the TILMD technique described above but with a different hnal result a hole instead of a cluster on the surface (Chi et al., 2000). 

Methods that investigate the interface as such are called in situ methods. In ex situ methods the electrode is pulled out of the solution, transferred to a vacuum chamber, and studied with surface science techniques, in the hope that the structure under investigation, such as an adsorbate layer, has remained intact. Ex situ methods should only be trusted if there is independent evidence that the transfer into the vacuum has not changed the electrode surface. They belong to the realm of surface science, and will not be considered here. 

In view of the fact that the above techniques examine single fibers embedded in a matrix block, application of the experimental measurements to practical fiber composites may be limited to those with small fiber volume fractions where any effects of interactions between neighboring fibers can be completely neglected. To relate the interface properties with the gross performance of real composites, the effects of the fiber volume fraction have to be taken into account. To accommodate this important issue, a modified version of the fiber pull-out test, the so-called microbundle pull-out test, has been developed recently by Schwartz and coworkers (Qui and Schwartz, 1991, 1993 Stumpf and Schwartz, 1993 Sastry et al., 1993). In... 

The microindentation technique (or push-out test as opposed to the pull-out test) is a single fiber test capable of examining libers embedded in the actual composite. The... 

This technique has the advantage of allowing the use of common CE capillaries without modification, which is of high practical importance. (The CE column exit may be tapered or pulled out to a fine tip in order to increase the local field strength.)... 

Figure 3.9. Scheme of the LB technique (a) deposition of the amphiphiles on the water subphase with the solid substrate submerged (b) by action of the barrier the ML is compressed (c) by pulling out the substrate vertically a ML is transferred to both sides of the substrate (d) a multilayered structure is built up by repeated up and down strokes of the substrate, (e) Distinct arrangements of LB Aims. 

All the techniques described here are easily conducted, so that both 0a and 0, may be observed. When the tilted plate method is used to evaluate the contact angle, 6r values are obtained if the plate has been pulled out (emersion) from the liquid 0a results if the plate is pushed into the liquid (immersion). Likewise, both values of 0 may be obtained from the Wilhelmy method, depending on whether the liquid is making an initial contact (0a) with the plate or is draining from it (6r). 

Also included in this group is the highly specific technique of immunoaffinity chromatography, in which an antibody directed against an epitope on the protein surface is used to pull out the desired protein from a mixture. 

Can the data be usefully analyzed Is there a sufficient data base for the technique to apply to my needs or must it be generated Can I analyze the data to pull out the information I need Can surface compounds be differentiated from alloy components Can atomic composition be obtained from the data Can different structures (island or layer) be distinguished from the data Does data relate to corrosion process of interest ... 

In dip coatings the article is completely immersed in a large tank containing a certain quantity of paint to be applied. The article is then pulled out excess coating drains back into the dip tank. This technique is used for metal primer application such as motorcar bodies. 

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