Applications, microscopy adhesives

Not only new techniques deserve attention, but also any new developments in old techniques, such as scanning electron microscopy (28). Scanning electron microscopy, for example, can now enhance the examination of the adhesive interface in greater detail. Two other old techniques have also found new applications in adhesive chemistry. One is dynamic mechanical analysis (29,30), which has been accepted for the study of pressure-sensitive adhesives and the curing mechanism of epoxy resins (31,32). The other is the use of a fluorescence probe to examine the curing mechanism (33). 

Surface-sensitive techniques for use in the study of adhesive bonding are discussed, including X-ray photoelectron spectroscopy and auger electron spectroscopy/scanning auger microscopy. Data analysis is considered, with reference to quantification, chemical-state information, depth-distribution information and surface-behaviour diagrams. Applications to adhesive bonding are described, particularly failure analysis, hydration of phosphoric acid-anodised aluminium and adsorption of hydration inhibitors. 100 refs. 

No reliable test methods for measuring the surface gloss of film laminates have, so far, been established. As such, the assessment of surface film gloss is best carried out visually. Evident graying is an indication of tiny air bubbles between board and film. These may be caused by inadequate application of adhesives, insufficient drying, or coalescence of the adhesive during lamination. Optical microscopy has also proven useful in confirming defect types in laminates. 

Hayes, R.A. and Ralston, J., Application of atomic force microscopy in fundamental adhesion studies. In Mittal, K.L. and Pizzi, A. (Eds.), Adhesion Promotion Techniques — Technological Applications. Dekker, New York, 1999, pp. 121-138. 

Burmeister JS, Olivier LA, Reichert WM, Truskey GA (1998) Application of total internal reflection fluorescence microscopy to study cell adhesion to biomaterials. Biomaterials 19 307-325... 

Understanding particle adhesion to a surface has applications in tissue engineering and particle processing. Experimental techniques for charactering particle adhesion to surfaces include laser trapping, AFM and microscopy with force measurement. 

Refractory high surface area oxides are deposited from slurries onto the walls of the channels that make up monoliths in order to provide an adequate surface area to support the active catalytic species. Washcoats such as AI2O3 and TiC>2 are commonly used for pollution abatement applications (auto exhaust, stationary NO abatement, etc.) where the monolith is usually a ceramic. Metal monoliths are finding increasing use however, they represent only a small percentage of the total monoliths used. Optical microscopy enables one to see that the catalyzed washcoat follows the contour of the ceramic surface. Figure 7 shows the AI2O3 washcoat-ceramic interface for a typical auto exhaust catalyst. In this case, no evidence of loss of adhesion between washcoat and ceramic can be seen. 

Atomic force microscopy [6, 7] is one of the most suitable methods for research carbon nanotubes. AFM allows to receive not only a relief of the studied sample, but also distribution of mechanical characteristics, electric, magnetic and other properties on its surface. With the help of AFM, controllable manipulation of individual CNTs and CNTs bundles became possible. In this paper we report our approach to manipulating SWCNTs bundles with lateral force microscopy. LFM gives possibility to study lateral forces that probe acts upon bundles. In spite of good visualization of LFM, its lack is absence of reliable techniques of quantitative interpretation of results. The new way of calibration developed ourselves has allowed to pass from qualitative estimations to quantitative investigations [8], The given calibration technique is much more exact, than others known till now [9, 10], and does not assume simplification. With the help of new technique we may study adhesion of bundles to substrate and adhesion of CNTs in bundle qualitatively in real time more easy way. This result will provide new possibilities for nanotube application. 

Scanning Probe microscopy techniques are extremely useful for analysing surfaces, but cannot lead to bulk information. They will be used each time surface properties are important, i.e. when surfaces are used for themselves (tribological applications, adhesion, etc.). However, in some cases, the study of transport phenomena (such as thermal or electrical conductivity) by modified AFM may lead to bulk characterisation such as the formation of a percolating nanotube network for instance. 

Discoid platelets become spherical with numerous short, blunt irregular membrane projections and extend long filopodia after ADP-activation in the suspension. In contrast, platelet adhesion and spreading to mica involve the formation of two different actin-based structures, filopodia and lamellipodia, and the increase of the platelet surface. These results indicate that the SFM which generates image contrast by a way completely different from light and electron microscopy is applicable for a hemostasis analysis. 

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