Dispersion types, schematic illustration

Figure 5.14. A schematic illustration of the superposition of the and Bloch sums at X viewed down [001]. The dispersion at X is driven primarily by ir-type and S-type d-d interactions.

Single Emulsions. These emulsions are formed by two immiscible phases (e.g. oil and water), which are separated by a surfactant film. The addition of a surfactant (or emulsifier) is necessary to stabilize the drops. The emulsion containing oil as dispersed phase in the form of fine droplets in aqueous phase is termed as oil-inwater (0/W) emulsion, whereas the emulsion formed by the dispersion of water droplets in the oil phase is termed as water-in-oil (W/0) emulsion. Figure 1 schematically illustrates the 0/W and W/0 type emulsions. Milk is an example of naturally occurring 0/W emulsion in which fat is dispersed in the form of fine droplets in water. 

Figure 9. Schematic illustration of anode reaction zones in Ni cermet-type (A) and Ni dispersion-type (B) SDC layers. Reproduced from Ref 24, Copyright (2005), by permission from The Electrochemical Society of Japan.

Figure 19.8. Schematic illustration of the multiscale modeling paradigm that, as of the year 2002, is most commonly followed in state-of-the-art work to predict the morphologies and properties of many types of mixtures, solutions, dispersions, blends, block copolymers and composites as well as to characterize the interfaces between the different phases in such systems. The items enclosed in the boxes with thick solid borders are important portions of the input into and/or the output of the simulations. The simulation methods are enclosed in the boxes with thin dashed borders. The prediction of properties will be discussed in Chapter 20. 

Figure 4. Schematic illustration of a scanning NIR spectrophotometer. The light energy comes from a tungsten-halogen lamp and is often JiviJed into separate wavelengths before interaction with the. sample (pre-dispersive). Instruments can also be post-dispersive. The way that wavelength selection is done is what differentiates most types of instruments (e.g., grating, FT, AOTF and Diode Arrays).

There are two types of conductive adhesives conventional materials that conduct electricity equally in all directions (isotropic conductors) and those materials that conduct in only one direction (anisotropic conductors). Isotropically conductive materials are typically formulated by adding silver particles to an adhesive matrix such that the percolation threshold is exceeded. Electrical currents are conducted throughout the composite via an extensive network of particle-particle contacts. Anisotropically conductive adhesives are prepared by randomly dispersing electrically conductive particles in an adhesive matrix at a concentration far below the percolation threshold. A schematic illustration of an anisotropically conductive adhesive interconnection is shown in Fig. 1. The concentration of particles is controlled such that enough particles are present to assure reliable electrical contacts between the substrate and the device (Z direction), while too few particles are present to achieve conduction in the X-Y plane. The materials become conductive in one direction only after they have been processed under pressure they do not inherently conduct in a preferred direction. Applications, electrical conduction mechanisms, and formulation of both isotropic and anisotropic conductive adhesives are discussed in detail in this chapter. 

Figure 5.10 Schematic illustration of two different types of heterogeneities in bulk isotactic polypropylene (iPP) (a) and how they are distributed, once the material is dispersed into a polystyrene amorphous phase in an 80/20 PS/iPP blend (b).

In the quantitative development in Section 24.4 below, we assume the flow to be ideal, but more elaborate models are available for nonideal flow (Chapter 19 see also Kastanek et al., 1993, Chapter 5). Examples of types of tower reactors are illustrated schematically in Figure 24.1, and are discussed more fully below. An important consideration for the efficiency of gas-liquid contact is whether one phase (gas or liquid) is dispersed in the other as a continuous phase, or whether both phases are continuous. This is related to, and may be determined by, features of the overall reaction kinetics, such as rate-determining characteristics of mass transfer and intrinsic reaction. 

The polymorphism of microemulsions described in Chap. 4 offers a variety of polymerisation sites. Figure 6.1 illustrates this with a schematic phase diagram for a water/oil/surfactant system. Depending on the aims in mind, the monomer may be incorporated in the droplet interior, in a sponge-type (bicon-tinuous) microemulsion, or in the continuous medium surrounding the disperse phase. Each of these possibilities has been explored, with varying degrees of success. 

In Figure 18.2, a schematic view of a spectrometer utilizing a number of optical filters is illustrated. Filters (up to about a maximum of 20) attached to a disk are used sequentially to select wavelengths for measurements by rotating the disk. Multiple regression analyses are often performed on the results of measurements with such filters. This spectrometer can be handled easily and is inexpensive, as neither an expensive optical element nor a high-precision mechanism is used. However, spectrometers of this type, because of their low spectral resolution and inability for continuous scan, have been replaced recently by dispersive or FT spectrometers. Only instraments marketed with a descriptive name such as ingredient analyzer are used now for specific analyses of food, cereals, tea, and so on. 

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