Specific interfadal area

OS 10] [R 10] [P 9] The specific interfadal area was varied for a phase-transfer reaction for four amide formations from two amines and two acid chlorides [23[. This was done by filling the solutions in normal test-tubes of varying diameter (1-5 X cm ) and using a micro reactor which had the largest specific interface (45 X cm ). The yields of all foiu reactions are highly and similarly dependent on... 

Haverkamp, V., Emig, G., Hessel, V., Liauw, M.A. and Lowe, H. (2001) Characterization of a gas/liquid microreactor, the micro bubble column determination of specific interfadal area, in Microreaction Technology- IMRET 5 Proceedings of the 5th International Conference on Microreaction Technology (eds M. Matlosz, W. Ehrfeld and J.P. Baselt), Springer-Verlag, Berlin, pp. 202-214. 

Stirrer type Specific interfadal area, uniformity of phase dispersion, emulsification Conversion n/i ratio 15]... 

In fiuid-fiuid (gas-liquid and liquid-liquid) systems, a solute usually difluses from one fluid phase into the other, in which the reaction then takes place. The product may pass back into the first non-reactive phase. In liquid-liquid and some gas-Uquid systems, the reaction may actually occur in both phases (e.g. oximation of cyclohexanone [4]). As with heat transfer, rapid reaction kinetics trend to exacerbate mass transfer limitations, especially when only small specific interfadal areas are available. In contrast to the specific surface area for heat transfer, fluid-fluid interfadal areas are dependent on physical properties and operating conditions. 

The specific surface is an important characteristic parameter of each porous body. It is defined as the interfadal area per gram of a solid phase, s = Splin, or as the interfadal area... 

From the above, it is clear that the specific surface area of the filler, which is closely related to filler shape, is of fundamental importance in the xmderstanding of the structtue-property relationship of nanocomposites. The change in particle diameter, layer thickness, or fibrous material diameter from micrometer to nanometer, changes the ratio by three orders in magnitude. At this scale, there is often distinct size dependence of the material properties. Furthermore, with the drastic increase in interfadal area, the properties of the composite are dominated more by the properties of the interface or interphase [2] and they play a much more important role in enhancing the mechanical properties of nanocomposites than in conventional composites or bulk materials [ 1 ]. 

This book is divided into specific subject areas of importance to polymer blend technology starting in Chapter 2 with the fundamentals. In this chapter, the thermodynamic relationships relevant to polymer blends are detailed along with discussions on the phase behavior and phase separation processes. Specific interactions in polymer blends leading to miscibility or improved mechanical compatibility are also discussed. The mean field theory and the association model are presented. The importance of the interfadal characteristics of phase separated polymer blends is also covered in Chapter 2. In Chapter 3, compatibiUzation methods for achieving compatibihty of phase separated blends are discussed, including the methods noted in Table 1.2. 

The topic of this book is forces acting between interfaces. There is no dear, unique definition of an interfacial force. One possible definition is as follows Interfacial forces are those forces that originate at the interface. For example, electrostatic double-layer forces are caused by surface charges at the interface. Such a definition would, however, not include van der Waals forces. For van der Waals interaction, the surface atoms do not have a distinct role compared to the bulk atoms. Still, van der Waals forces substantially contribute to the interaction between small particles. One could define surface forces as all interactions that increase proportional to the interfacial area. Then, for certain geometries gravitation should also be induded. Gravitation is, however, not described here. On the other hand, hydrodynamic interactions would be excluded because thqr depend on the specific shape of interacting interfaces and not only on the interfadal area. 

Dr. Miller s research interests center on equilibrium and dynamic phenomena in oil/water/surfactant systems, specifically interfacial stability and behavior of emulsions, microemulsions and foams and their application in areas such as detergency, enhanced oil recovery and environmental remediation. He is a Fellow of the American Institute of Chemical Engineers and a member of the American Chemical Society, American Oil Chemists Society, International Association of Colloid and Interface Scientists, and the Society of Petroleum Engineers. He has published numerous research papers and review articles on interfadal phenomena, served on the editorial boards of leading journals in the field, and given invited lectures at conferences, universities and industrial laboratories in many countries. 

AGs is given by the product of area of the nudeus and the specific surface energy (solid/liquid interfadal tension) y AGv is related to the relative supersaturation... 

Parsons and Zobel plot — In several theories for the electric double layer in the absence of specific adsorption, the interfadal capacity C per unit area can formally be decomposed into two capacities in series, one of which is the Gouy-Chcqjman (-> Gouy, -> Chapman) capacity Cgc. 1/C = 1/Ch + IjCcc- The capacity Ch is assumed to be independent of the electrolyte concentrations, and has been called the irmer-layer, the... 

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