Morphological measurements techniques

The reactivity of oxide supported metals has received considerable attention because of the importance of such systems in heterogeneous catalysis. The morphology (structure and size) of the supported particle and its stability, the interaction of the particle with the support, and the crossover of adsorbed reactants, products and intermediates between the metal and oxide phases are all important in determining the overall activity and selectivity of the system. Because of the relative insensitivity of an optical technique such as IR to pressure above the catalysts, and the flexibility of transmission and diffuse reflection measurement techniques, vibrational spectroscopy has provides a considerable amount of information on high area (powder) oxide supported metal surfaces. Particularly remarkable was the pioneering work of Eichens and Pliskin [84] in which adsorbed CO was characterised by IR spectroscopy on... 

Rheo-optical techniques (46 8) afford information on the strain dependence not only of stress but also of optical quantities associated directly with the structure or molecular morphology. The techniques were developed extensively for crystalline polymers to investigate the molecular deformation mechanism underlying the tensile elongation. In this part, the chain orientation behavior is characterized by infrared dichroism measured simultaneously with tensile deformation at a constant rate of elongation. 

Caution must be exercised in interpretation of the physical data for the tetracyanoplatinate complexes (as well as all other one-dimensional systems) because purity and morphology are extremely critical for one-dimensional systems. For example, a 1.00 x 0.01 x 0.01 mm perfect needle crystal of K2Pt(CN)4Xo.3 would contain — lx 10 parallel strands each of 3.5 x 10 collinear platinum atoms. Thus, purity (foreign impurities, end groups, and/or crystalline defects) levels of one part per million indicate that each strand averages more than three defects, which may drastically alter some (and in particular transport) measurements. Besides the intrinsic purity problem of one-dimensional systems, the physical properties of K2Pt(CN)4-Xo.3(H20)a are a strong function of hydration. Dehydration alters the crystal structure and thus properties of the complexes (78). Care must be maintained to ensure that dehydration is not caused by the measurement technique. For... 

This paper begins with an overview of the analysis method and continues to describe a method called mathematical morphology. This technique is used to simplify grey images prior to their measurement and therefore has many uses in image analysis. 

A new measurement technique, in-situ AFM combined with XPS, scanning AES, and continuous argon sputtering reveals that the films are not uniform. Nanostructures at the lithium surface consisting of grain boundaries, ridge-lines, and flat areas control the morphology of lithium electrodeposition [381, 382, 395]. 

The organization of the present chapter is as follows. Dielectric techniques for molecular dynamics studies, in particular broadband dielectric spectroscopy (DS) and thermally stimulated depolarization currents (TSDC) techniques are shortly presented in the next section. Section 3, devoted to ionic conductivity measurements and analysis, focuses mostly on analysis, as the measuring techniques and equipment are often similar to those used for DS. The microphase separation and morphology of segmented PUs is discussed in the following Section 4, which completes the first introductory part of the chapter. Results obtained with selected PTE are presented in Section 5, followed by a larger Section 6 devoted to PU ionomers with ionic moieties in either of the HS and SS. PU ionomers of the latter type are often based on poly(ethylene oxide) (PEO) as the SS component and, for this reason. Section 6 includes a discussion of telechelics based on PEO, which may serve as model systems for PU ionomers. In Section 7, we discuss recent results obtained with nanocomposites based on PTE, a topic attracting much current interest, before we conclude with Section 8. 

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