Interface measurement

Rasing Th, Shen Y R, Kim M W, Valint P Jr and Bock J 1985 Orientation of surfactant molecules at a liquid-air interface measured by optical second-harmonic generation Phys. Rev. A 31 537-9... 

Yackoboski K, Yeo Y H, McGonigal G C and Thomson D J 1992 Molecular position at the liquid/solid interface measured by voltage-dependent imaging with the STM Ultramicroscopy 42-44 963... 

We saw in Chapter 6 that the speed of a diffusive transformation depends strongly on temperature (see Fig. 6.6). The diffusive f.c.c. b.c.c. transformation in iron shows the same dependence, with a maximum speed at perhaps 700°C (see Fig. 8.1). Now we must be careful not to jump to conclusions about Fig. 8.1. This plots the speed of an individual b.c.c.-f.c.c. interface, measured in metres per second. If we want to know the overall rate of the transformation (the volume transformed per second) then we need to know the area of the b.c.c.-f.c.c. interface as well. 

The simulated free surface of liquid water is relatively stable for several nanoseconds [68-72] because of the strong hydrogen bonds formed by liquid water. The density decrease near the interface is smooth it is possible to describe it by a hyperbolic tangent function [70]. The width of the interface, measured by the distance between the positions where the density equals 90% and 10% of the bulk density, is about 5 A at room temperature [70,71]. The left side of Fig. 3 shows a typical density profile of the free interface for the TIP4P water model [73]. 

Interface Measured Adhesion Tension Calculated Contact Angle... 

In the experiments on the Jt-A characteristics, it has been usually assumed that thermal equilibrium will be attained easily if the experiment is performed using a slow rate of compression of thin film at the interface. Measurements under thermal equilibrium are, of course, the necessary condition to obtain the physico-chemical properties of the individual "phase" of the lipid ensemble. 

Figure 6. Effects of preheating of sample suspensions at 98°C for 30 min on the in situ emission Mossbauer spectra of Sn-119 arising from pentavalent Sb-119 at the hematite/0.25 mol dm 3 LiCl solution interface (measurement at room temperature) (A1) Before heating, pH 6.6 and (A2) after heating, pH 7.9 (B1)...

Diffusive boundary iayer at the sediment-water interface measured with oxygen microelectrodes in Danish coastai sediments in a totai water depth of 15m. Source-. After Gundersen, J. K., and B. B. Jorgensen (1990). Nature 345, 604-607. 

Majumda, B.S. and Miracle, D.B, (1996). Interface measurement and applications in fiber reinforced MMCs. Key Eng. Mater. 116-117, 153-172. 

Kirchner, W., F. Welter, A. Bongartz, J. Karnes, S. Schweighoefer, and U. Schurath, Trace Gas Exchange at the Air/Water Interface Measurements of Mass Accommodation Coefficients," J. Atmos. Chem., 10, 427-449 (1990). 

Kirchner, W Welter, F Bongartz, A., Karnes, J., Schwdghofer, S., and Schurath, U. (1990) Trace gas exchange at the air/water interface measurements of mass accommodation coefficients, J. Atm. Chem. 10,427-449. 

Extensive interface research is crucially essential for developing long-life, cost-effective, multilayer, polycrystalline, thin-film stacks for SECS. Microchemical analysis and other interface measuring techniques must be employed to solve the interfacial stability problems in the stacks. Important topical areas in solar materials interface science include thin films grain, phase, and interfacial boundaries corrosion and oxidation adhesion chemisorption, catalysis, and surface processes abrasion and erosion photon-assisted surface reactions and photoelectrochemistry and interface characterization methods. 

Liquid-solid interface measurements are extremely demanding and require nuclear or sonic sensing. The sonic sensor must always be submerged because a gas phase will either disrupt the measurement entirely or appear to be the solid. In special noncoating cases, optical sensors have also worked. 

A flow-pattern map comprises dispersed flow, annular flow, slug-dispersed flow and slug-annular flow [278]. The highest specific interface measured amounts to 16 000 m2/m3. A porous surface structure (100 cm2) in the reaction channel can be generated by a sulfurhexafluoride plasma etch process with silicon nitride masking [278],... 

An alternative approach to producing a differently functional surface is to use spin coating techniques. This was done by Turner et al. [68], who spun cast layers of polystyrene onto a silica surface. They investigated the nature of the surface and of SDS adsorbed to that surface by neutron reflectivity and IR-ATR. A thin layer of polystyrene, 275 A, was established. The subsequent SDS adsorption was consistent with a monolayer 15 A thick and an adsorbed amount similar to that observed at the air-solution interface. Measurements above the cmc of SDS showed clearly the effects on the adsorption pattern of dodecanol impurities in the SDS. 

Figure 4. Settler interface measuring device. The upper part of the figure is a stereoscopic drawing of the level transducer. Note that one electrode is covered with PTFE insulation, except for the lower tip. Electrode materials have been graphite or titanium. Lower part of the figure shows the level measuring circuit.

Two Liquid/Liquid interfaces. Measuring the interactions between two liquid droplets with AFM is a natural extension of the one droplet problem and more relevant to emulsion stability. The first and only such measurement is between alkane droplets in... 

Fig. 4. Mass-transport-corrected Tafel piot for oxygen reduction at the Pt/Nafion interface measured with the system described in [4]. (Reprinted by permission of the Electrochemical Society).

Yamaguchi, S. and Tahara, T. (2004) Precise electronic yrf)] spectra of molecules adsorbed at an interface measured by multiplex sum frequency generation. 

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