Zipper effect

Fig. 9. The effect of voids due to poor wetting on adhesive strength, (a) The zippering effect of voids aligned in the plane of shear, (b) Macro-voids in the resin formed during the manufacture of a carbon fiber reinforced prepregs. (c) Micro-voids caused by axial crenulations along carbon fiber surfaces.

Furthermore, this complexation/dissociation change may occur with an accompanying cooperative chain-chain zipper effect the drastic change or transition of solubility implies extensive chain-chain interactions. 

Fig. 12. Zipper effect in the process of formation and dissociation of interpolymer complex...

Ultrastructural patterns that arise when amino acids or small peptides interact with mineral surfaces have been studied in some detail99,100). A poly-L-alanine solution evaporated at 40 °C on a rhombohedral plane of R-quartz deposits the peptide principally in a-conformation. Chain-folded helices are aligned in the form of lamellae which exhibit a sharp phase boundary at the organic-mineral contact zone (Fig. 9). Frequently the lamellae are split along the direction of their fold axis ("zipper effect ). Insertion of 0-pleated sheets running perpendicular to the long axis of the lamellae act as dispersion forces and cause the formation of cross-0-... 

FIGURE 13.16 Diagram illustrating the kinetic zipper effect of a polymeric additive in CMP slurry that functions to stabilize the adsorption from removal under certain applied forces. 

Depolymerized Alginic Acid Solution NMR Studies. Studies are being conducted with depolymerized alginic acid. In these samples, the MG blocks were removed by acid hydrolysis lea dng shorter chains contmning mostly GG or MM blocks. For whole alginic acid, complexation of one ion to a GG block leads to a zipper effect. If two or more metal ions bind to GG blocks that are separated by one... 

Hydrogen bonds. The base pairs, on close approach, form a preferred set of hydrogen bonds, three between GC pairs and two between AT pairs. The cumulative zippering effect of these hydrogen bonds keeps the strands in correct complementary orientation. 

Hybridization of unsonicated DNA tends to have a "zippering" effect and may include as dsDNA sequences which are heterologous. Sonication breaks the DNA into short lengths (4-500bp) in which the sequences are more likely to be mainly homologous or mainly heterologous. 

McCarthy, D. M. (2003) The trans-Pacific zipper effect Disjunct sister taxa and matching geological outlines that link the Pacific margins. Journal of Biogeography, 30 1545-1561. 

The most important type of inhibitor to the oil industry is the filming inhibitors. One end of the inhibitor molecule is adsorbed onto the metal surface. The non-polar tail of the inhibitor molecule is oriented in a direction generally vertical to the metal surface. It is believed that the hydrocarbon (non-polar) tails mesh with each other in a sort of zipper effect to form a tight film that repels aqueous fluids, estabhshing a barrier to the chemical and electrochemical attack of fluids on the base metal. A secondary effect is the physical adsorption of hydrocarbon molecules from the process fluids by the hydrocarbon tails of the adsorbed inhibitor molecules. This increases both the thickness and effectiveness of the hydrophobic barrier to corrosion. 

Orthocyclophane 9, [2.2]metacyclophane 10-12, [23](l,3,5)cyclophane 13-14, and [24](l,2,4,5)-qrclophane 15 were successfully prepared by irradiation through a Pyrex filter of the appropriate di-, tri-, and tetravinylbenzene in benzene solution at room temperature. The yields obtained were not optimized at that time (Table 19.2). It is clear that the more strained the cyclophane is, the less product is formed. [2.2]Paracyclophane was not obtained by this route, although (24] (l,2,4,5)cyclophane 15, which contains the paracyclophane moiety, was prepared. It is likely that a zipper effect could be operative in this cycloaddition following the first metacyclophane formation. ... 

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