Structure of deposits

Less frequently observed growth forms are pyramids, spirals, whiskers, and dendrites. The structure of deposits is discussed further in Chapter 16. 

Cation Cationic structure and size will affect the viscosity and conductivity of the liquid and hence will control mass transport of metal ions to the electrode surface. They will also be adsorbed at the electrode surface at the deposition potential and hence the structure of the double layer is dominated by cations. Some studies have shown that changing the cationic component of the ionic liquid changes the structure of deposits from microcrystalline to nanocrystalline [27]. While these changes are undeniable more studies need to be carried out to confirm that it is a double layer effect. If this is in fact the case then the potential exists to use the cationic component in the liquid as a built-in brightener. 

The structure of deposits on the superheater tubes in pulverized coal-burning boilers is shown in Figure 3.3. Above 700°C, the corrosion rate is decreased significantly due to decomposition of these complex liquid trisulfates. Once the liquid phase has been removed, the corrosion is due to oxidation in contact with flue gas. 

FIGURE 3.3 Structure of deposit on superheater tubes in pulverized coal-burning boilers. (Reproduced from Natesan J., High-Temperature Corrosion in Power-Generating Systems, http //www.ipd.anl.gov/ anlpubs/2002/05/43234.pdf, 2002. With permission.)... 

The metallic mesh allows the ink to pass through when the ink is under the scraper s pressure. The structure of deposits is controlled by the presence of a polymeric film covered by a mesh at the places where the paste is not to be deposited. 

Recently XAS investigations were used to explore the Cu UPD process as a function of applied potential on carbon-supported Au nanoparticles [23]. Analysis of both the Cu and Au extended X-ray absorption fine structure (EXAFS) indicated only partial monolayer coverage at potentials where a complete Cu monolayer is predicted for single crystals. The structure of deposited Cu was found to be more consistent with Cu cluster formation at defects in the Au surface than the presence of a smooth monolayer due to lower than expected numbers of Au-Cu neighbors and Cu-Cu neighbors fitted in EXAFS analysis. The absence of a uniform mono-layer of Cu on the nanoparticles implies that subsequent displacement of Cu by Pt is unlikely to result in the formation of a uniform Pt shell [23]. 

The present report is devoted to the epitaxial growth of molybdenum and tungsten, electrodeposited from oxide and halide melts onto monociystalline molybdenum and tungsten substrates with four orientations (<001> <011> <112> <111>). In particular to study the structure of deposits, the relative growth rates of monocrystalline planes with different oientations and the process of destruction of epitaxial growth. 

A layered structure of deposition of ceUulose within the fiber is obtained, as shown in the cross-section of a highly swollen single fiber see Figure 3. The details of the biosynthesis of cellulose are not clear however, the layered deposition may be due to day-night, temperature, moisture or other ecological variations. ... 

The aim of this chapter is to introduce an approach towards geological modeling which is able to encompass the structure dictated by sequence stratigraphy, and fulfill modeling constraints from a wide range of disciplines. Motivated by the hierarchical structuring of depositional sequences, a hierarchical segmentation approach is presented. 

---