Structure and morphology characterization

Fig. 17.2 Structural and morphological characterization of W03/CNT sheets prepared at 300 °C and 400 °C (a), (d) SEM images showing the morphology of W03/CNT sheets (b), (e) TEM images showing the W03 wrapping on the CNT surface (c), (f) HRTEM images showing the lattice images of W03. Reprinted with permission from [20], Copyright 2012, The Royal Society of Chemistry.

Various procedures for the preparation of 10 03 films and nanoparticles, including evaporation, sputtering, laser deposition, spray pyrolysis, thermal oxidation of predeposited hi and electrochemical deposition have been reported [27], The structural and morphological characterization of lri203-based materials has been carried out by... 

Yip, C. M., DeFelippis, M. R., Frank, B. H., Brader, M. L., and Ward, M. D. 1998. Structural and morphological characterization of ultralente insulin crystals by atomic force microscopy Evidence of hydrophobically driven assembly, Biophys J 75,1172-1179. 

The structural and morphological characterization of MDF cements in dry and water-stored state was evaluated by contact angle measurements and atomic force microscopy, aiming to deeply understand the complex processes that occur during cement hydration. 

Further, the main thermal events identified by analyzing bone tissue batches will be described and discussed. A correlation with the results obtained by modern complementary structural and morphological characterization techniques follows. 

Falini, G., Foresti, E., Lesci, G. Roveri, N. (2002) Structural and morphological characterization of synthetic chrysotile single crystals. Chemical Communications, 1512-1513. 

Siloxane containing interpenetrating networks (IPN) have also been synthesized and some properties were reported 59,354 356>. However, they have not received much attention. Preparation and characterization of IPNs based on PDMS-polystyrene 354), PDMS-poly(methyl methacrylate) 354), polysiloxane-epoxy systems 355) and PDMS-polyurethane 356) were described. These materials all displayed two-phase morphologies, but only minor improvements were obtained over the physical and mechanical properties of the parent materials. This may be due to the difficulties encountered in controlling the structure and morphology of these IPN systems. Siloxane modified polyamide, polyester, polyolefin and various polyurethane based IPN materials are commercially available 59). Incorporation of siloxanes into these systems was reported to increase the hydrolytic stability, surface release, electrical properties of the base polymers and also to reduce the surface wear and friction due to the lubricating action of PDMS chains 59). 

Full evaluation of functionalized ceramics requires the ability to characterize the spatial variations in structure and morphology. Using NMRI, it is possible to map the underlying structure on a spatial scale of hundreds of microns. 

Until quite recently the very initial stages of metal deposition were difficult to characterize in detail by structure- and morphology-sensitive techniques. As a consequence and for practical purposes - multilayers were more useful for applications than monolayers - the main interest was focussed onto thick deposits. Optical and electron microscopy, ellipsometry and specular or diffuse reflectance spectroscopy were the classic tools, by which the emerging shape of the deposit was monitored [4-7],... 

The change in authors has not altered the basic concept of this 4th edition again we were not aimed at compiling a comprehensive collection of recipes. Instead, we attempted to reach a broader description of the general methods and techniques for the synthesis, modification, and characterization of macromolecules, supplemented by 105 selected and detailed experiments and by sufficient theoretical treatment so that no additional textbook be needed in order to understand the experiments. In addition to the preparative aspects we have also tried to give the reader an impression of the relation of chemical structure and morphology of polymers to their properties, as well as of areas of their appUcation. 

In this context numerous changes were made. The chapter Properties of Polymers was revised and a new section Correlations of Structure and Morphology with the Properties of Polymers was added. The chapter Characterization of Macromolecules was revised and enlarged. 15 examples have been deleted as they did no longer represent the state of the art and/or were of minor educational value. Several new experiments (plus background text) were added, as, for example controlled radical polymerization - enzymatic polymerization - microemulsions - polyelectrolytes as superabsorbants - hyperbranched polymers - new blockcopolymers - high impact polystyrene - electrical conducting polymers. 

High-resolution transmission electron microscopy (HRTEM) has matured markedly in the preceding decade and has emerged as a powerful technique for investigation of nanostructured metal catalysts at the atomic level, even under working conditions. The ability to image the dynamic structure and morphology of supported metal nanocluster catalysts in such detail makes HRTEM an essential complement to the arsenal of spectroscopic techniques used for characterization of... 

After the process of synthesis, a thorough characterization of the obtained materials is necessary. It is almost impossible to understand the properties of a material and, consequently, its proper application, if we do not understand its composition, structure, and morphology. A task of fundamental importance in the physical chemistry of materials, as in all material sciences, is characterization. ... 

Understanding the dependence of film structure and morphology on system layout and process parameters is a core topic for the further development of ZnO technology. Work is being performed on in situ characterization of deposition processes. Growth processes are simulated using Direct Simulation Monte-Carlo (DSMC) techniques to simulate the gas flow and sputter kinetics simulation and Particle-ln-Cell Monte-Carlo (PICMC) techniques for the plasma simulation [132]. 

For the analysis of NCM electrical resistance the NCM samples obtained by the arc-discharge method were taken. A part of the samples was subjected to thermochemical treatment in order to change its structure and phase composition. The X-ray diffraction analysis and TEM were used to characterize the structure and morphology NCM [3], The structure and phase composition of each sample are described in Table 1. Evidently, the ratio of ordered (CNT) to disordered phase contents increases from sample I to sample V. Besides the particles of nanographite were found in two last samples. 

Figure 6 TEM characterization of the structure and morphology of Pd nanoparticles supported on MgO(l 0 0). (a) Electron diffraction pattern (b) top-view micrograph (c) profile view micrograph of an individual particle (d) drawing of the truncated octahedron shape of a Pd particle (e) shape of a large coalesced particle (0 truncated pyramid shape of a small (<7 nm) Pd particle.

The pressure gap is also a considerable challenge in model catalysis. It has been only recently addressed thanks to new techniques that can work under high-pressure conditions (relative to UHV). As we have seen in the introduction, several techniques are now available but they have up to now rarely been applied on supported model catalyst. Indeed we can expect that the effect of the pressure can be more dramatic than on extended surfaces because small particles are easier subject to structural and morphological evolution during reaction. Thus, it will be necessary to probe the reactivity and to characterize structurally the model catalyst in realistic reaction conditions. Microscopy techniques like STM, AFM, and TEM, coupled with activity measurements are suitable. The ultimate goal would be to measure the reactivity at the level of one supported cluster and to study the coupling between neighbouring clusters via the gas phase and the diffusion of reactants on the support. 

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