Surface Morphology Characterization

Numerous works have been implemented on tellurium electrochemistry and its adsorption at metal surfaces. The morphological structures of electrodeposited Te layers at various stages of deposition (first UPD, second UPD, and bulk deposition) are now well known [88-93]. As discussed in the previous paragraphs, Stickney and co-workers have carried out detailed characterizations of the first Te monolayer on Au single-crystal surfaces in order to establish the method of electrochemical atomic layer epitaxy of CdTe. 

Surface Morphology. The initial Integrity of an adhesively bonded system depends on the surface oxide porosity and microscopic roughness features resulting from etching or anodization pretreatments. (17) The SAA surface characterized in this study consists of a thick (9 ym), porous columnar layer which provides excellent corrosion resistance in both humid and aggressive (i.e., Cl ) media. I The thinner FPL oxide provides a suitable substrate surface for evaluating the candidate inhibitors. 

Figure 6.9. TMAFM image taken at ambient conditions of a TTF-TCNQ thin film (thickness um) grown on KCl(lOO), revealing its polycrystalline morphology. Reprinted from Surface Science, Vol. 482 85, C. Rojas, J. Caro, M. Gri-oni and J. Fraxedas, Surface characterization of metallic molecular organic thin films tetrathiafulvalene tetracyanoquinodimetane, 546-551, Copyright (2001), with permission from Elsevier.

Starting with basic physical concepts and synthetic techniques, the book describes how molecules assemble into highly ordered structures as single crystals and thin films, with examples of characterization, morphology and properties. Special emphasis is placed on the importance of surfaces and interfaces. The final chapter gives a personal view on future possibilities in the field. 

In a later study by the Schmidt group (27), electron microscopy was used to characterize morphological changes in microspheres (<0.6 cm in diameter) of Pt, Rh, Pd, and Pt-Rh alloy in a number of reaction environments the reactions were ammonia oxidation, ammonia decomposition, and propane oxidation. No other experimental techniques, such as weight-loss measurements, were employed. After prolonged exposure to reaction mixtures of ammonia and air at temperatures less than 727°C, the surfaces of the spheres were reconstructed to favor specific crystal planes. The structure of the facets was found to be a function of the reaction mixture, temperature, and metal (Fig. 13). In the same reaction mixtures, as well as in pure ammonia at higher temperatures... 

Furukawa N, Yamada Y, Furukawa M.YuasaM, KimuraY (1997) Surface and morphological characterization of polysiloxane-block-polyimides. J Polym Sci Part A Polym Chem 35(11) 2239... 

In this chapter, we briefly describe several techniques that provide state-of-the-art characterization of the structure and morphology of single-crystal surfaces. Such surfaces serve as models to understand and predict the behavior of nanoparticles or are directly relevant as supports (substrates) for nanoparticles. It is beyond the scope of this chapter to provide a comprehensive review of work in this field, but rather we provide a number of examples of results obtained by utilizing these surface characterization techniques which illustrates their applications. 

Morphology and surface roughness of PHB film exposed to corrosive medium (phosphate buffer) have been studied by the AFM technique. This experiment is important for surface characterization because the state of implant surface determines not only mechanism of degradation but also the protein adsorption and cell adhesion that are responsible for pol5mier biocompatibility [30], As the standard sample, we have used the PHB film with relatively low MW =170 kDa. 

S.F. Lascelles, S.P. Armes, P.A. Zhdan, S.J. Greaves, A.M. brown, J.F. Watts, S.R. Leadley, and S.Y. Luk, Surface characterization of micrometre-sized, pol3fpyrrole-coated polystyrene latexes verification of a core-shell morphology, J. Mater. Chem., 7(8), 1349-1355 (1997). 

Compared to morphology, filler chemistry has been only slightly studied, partly because of the difficulty of such characterizations and more probably because since the 1970s reinforcement is broadly considered as a physical interaction between elastomer and filler. So carbon black chemical characterizations mainly date from the 1960s, and few new technical methods have been applied to carbon black surface characterization since then. The situation is somewhat different for silicas, because silica reinforcement is the consequence of a chemical reaction of silane with silica surface. Few studies have been published in the elastomer reinforcement area, probably because silica surface was already well characterized for other applications. 

Bulk characterization yields information on the macroscopic properties of the biomaterial such as thermal, mechanical, solubility, optical, and dielectric properties. Surface characterization yields morphological information that is critical for interfacing the implant or drug delivery device with the host tissue. This could be achieved by microscopic and spectfoscopic methods. Next in the hierarchy is the characterization of processes such as biodegradation mechanism and kinetics under biomimetic in vitro conditions. Cases of implanted device failure need to be assessed by systematic interrogation of explanted medical devices. After knowing the basic characteristics of the biomaterial, real-time investigation of in vivo processes plays a major role in the successful journey of an implant. 

Surface and Morphological Characterization 20.4.4 In Vivo Biocompatibility Evaluation 343... 

Lascelles, S.F., et al. 1997. Surface characterization of micrometre-sized, polypyrrole-coated polystyrene latexes Verification of a core-shelT morphology. / Mater Chem 7 1349. 

It was demonstrated in a number of cases [24,25] that changes of surface and morphology of ceramic powders can be characterized by DSA under in-situ conditions of their treatment. 

Yuan LY, Chen CS, Shyu SS, Lai JY, Plasma surface treatments on carbon fibres. 1. Morphology and surface analysis of plasma etched fibres. Composites Sci Technol, 45(1), 1-7, 1992. Commercon P, Wightman JP, Surface characterization of plasma treated carbon fibres and adhesion to a thermoplastic pol5mer, J Adhesion, 38(1-2), 55-78, 1992. 

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