Microstructure interface stabilization

Rheology and Microstructure of Interfaces Stabilized by Mixed Proteins and Surfactants A Computer Simulation Study... 

The product microstructure is specified as follows. The product is an oil in water emulsion. The oil droplet size should be around 2pm. The emulsion is stabilized by two different emulsifiers, El and E2. Both emulsifiers should be at the interface in a certain ratio. Since there is an excess level of El, the remaining El should be dispersed in the water phase. The levels of the oil, El and E2 and the water phase are specified. The microstructure is shown schematically in Figure 3. 

Concerning the structure of dispersed CLAs, the model originally proposed by Sebba [57] of a spherical oil-core droplet surrounded by a thin aqueous film stabilized by the presence of three surfactant layers is, in our opinion, essentially correct. However, there is still little direct evidence for the microstructure of the surfactant interfaces. From an engineering point of view, however, there is now quantitative data on the stability of CLAs which, together with solute mass transfer kinetics, should enable the successful design and operation of a CLA extraction process. 

Spent fuels vary in microstructure, and phase and elemental distribution depending on the in-core reactor operating conditions and reactor history. The chemical stability of spent U oxide fuel is described by local pH and Eh conditions, redox being the most important parameter. However, the redox system will also evolve with time as various radionuclides decay and the proportion of oxidants and reductants generated at the fuel/water interface changes with the altering a-, (J-, y-radiation field and with the generation of other corrosion products that can act as... 

Moschakis, T., Murray, B.S., Dickinson, E. (2005). Microstructural evolution of viscoelastic emulsions stabilized by sodium caseinate and xanthan gum. Journal of Colloid and Interface Science, 284, 714-728. 

Mesh Microcontactor A mesh microcontactor contains a microstructured plate with regular circular openings through which separate gas and liquid streams come into contact [270,271]. Stability of the interface and prevention of breakthrough are achieved by adjusting the pressure. Gas-liquid operation requires a low gas flow... 

In order to be able to optimize the mechanical stability of such systems, more tests must be performed along with in-depth microstructural examination of the interfaces. 

Emulsifiers stabilize emulsions in various ways. They reduce interfacial tension and may form an interfacial film that prevents coalescence of droplets. In addition, ionic emulsifiers provide charged groups on the surface of the emulsion droplets and thus increase repulsive forces between droplets. Emulsifiers can also form liquid crystalline microstructures such as micelles at the interface of emulsion droplets. These are formed only at emulsifier concentrations larger than the critical micelle-forming concentration. These microstructures have a stabilizing effect. 

Engelskirchen, S., Eisner, N., Sottmann, T. and Strey, R. (2007) Triacylglycerol microemulsions stabilized by alkyl ethoxylate surfactants - A basic study Phase behaviour, interfacial tensions and microstructure. /. Colloid Interface Sci., 312, 114-121. 

The observed differences in scale thickness and microstructure between the oxide scales and subsurface zones at the various oxidation temperatures seem to be mainly attributed to the different diffusion rates at the respective temperatures. Since the oxidation products formed do not show any differences in the temperature range of 800°C to 1000°C it is concluded that no significant effect of the thermodynamic stability on the composition and structure of the oxidation products occurs. From the calculations of Rahmel and Spencer [21] it is known, however, that the activity of A1 and Ti in the system Ti-Al varies depending on the temperature. Thus it has to be taken into account that the temperature may have an influence on the expansion of the phase fields of some important phases in the system Ti-Al-N-O. Nevertheless it is evidently the temperature which mainly influences the kinetics because the structure of the metal/oxide interface, the formation of titanium nitrides, A127039N and an aluminium depleted metal phase is on principle always very similar. In this way the effect of different temperatures can, to a certain degree, be interpreted as that of a shift in the different stages of the oxidation process. 

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