Dynamic adhesion

The dynamical adhesion process described in this section is also referred to as adhesion hysteresis. We will come back to this subject in later sections when discussing the correlation between adhesion and friction. 

From the discussions on dynamic adhesion and wearless friction, one may realize that the two events originate from... 

The process of viscoelastic braking just described has certain parallels with the dynamic adhesion of elastomers. When, for example, a rubber strip is peeled from a rigid substrate, the effective, or apparent, work of adhesion, W, is usually much greater than the intrinsic, or reversible, energy of adhesion, Wq, given by the Dupre equation [15] ... 

However, use of the loss tangent in Eq. (13) is an oversimplification. Instead, we shall make use of an empirical dissipation law obtained in the study of rate-dependent adhesion of elastomers (19). Maugis and Barquins [19], in order to explain the dynamic adhesion of elastomers in a variety of test configurations (peel, flat punch, etc), proposed the following relation ... 

The methods described below outline three dynamic adhesion/aggregation assays used to assess the in vitro and/or ex vivo efficacy of platelet antagonists (1) a viscometric-flow cytometric assay to measure shear-induced platelet-platelet aggregation in the bulk phase, (2) a perfusion chamber coupled with a computerized videomicroscopy system to visualize in real time and quantify (a) the adhesion and subsequent aggregation of platelets flowing over an immobilized substrate (e.g. extracellular matrix protein) and (b) free-flowing monocytic cell adhesion to immobilized platelets. 

Microscopic fluid distribution non-ideality is caused by fluid dynamic adhesion between the fluid and the adsorbent particle inside the microscopic channels of the packed bed. Adhesion results in a higher fluid velocity in the middle of the channel than at the channel walls (Fig. 2.9a). Solute molecules in the middle of the channel thus have a shorter retention time than those at the channel walls. 

This has been discussed extensively by Evans and Ritchie in the context of the dynamic adhesive strength of molecular bonds [89]. They also consider regimes in which F is extremely large and extremely small (approaching thermal equilibrium). 

V. DYNAMIC ADHESION MODELING OF MOLECULARLY WELL-DEFINED SYSTEMS... 

Dynamic adhesion n. The ability of a cord-to-rubber bond to resist degradation resulting from flexure. 

Obviously, much developmental work will have to be done on this new system, such as the evaluation of dynamic adhesion properties, cost analysis, and so on. Important factors in favour of the new systems are their ease of application, simple bath make-up and their... 

Moon, S., Swearingen, S. Foster, M. D. (2004). Scanning Probe Microscopy Study of Dynamic Adhesion Behavior of Polymer Adhesive Blends. Polymer, Vol. 45, pp. 5951-5959, ISSN 0032-3861... 

This material is a promising candidate for application in dynamic adhesive systems, such as robot soles adapted for locomotion. Robots that could climb smooth and complex inclined terrains, as insects and lizards do, would have many applications such as exploration, inspection, or cleaning. Walking machines usually use suckers to hold onto vertical surfaces or under a surface. A primary disadvantage of this attachment principle is large energy consumption for... 

FIGURE 5. Adhesion of BL6 cells to mouse ECs is based on interaction of GM3 (expressed on BL6 cells) with Gg3 or LacCer (expressed on ECs). (A, B) Laminar flow dynamic adhesion system. Wall shear stress was calculated as described by Lawrence et al. (1990). One of the parallel plates was coated with Gg3-liposome, LacCer-liposome, FN, or laminin (LN), and BL6 cells suspended in medium were passed through the laminar flow chamber. See Kojima etal. (1992c) for experimental details. Adhesion based on Gg3 or LacCer predominated over that based on FN or LN, regardless of shear stress. (C) Static adhesion system. FN- or LN-dependent adhesion became obvious only after 30 min of incubation. In contrast, Gg3- or LacCer-dependent adhesion were obvious at 20 min. These results suggest that there is a longer lag time for integrin-based cell adhesion compared to adhesion based on carbohydrate-carbohydrate interaction, in a static system. 

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