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Interfacial thickness observed with

The oscillations observed with artificial membranes, such as thick liquid membranes, lipid-doped filter, or bilayer lipid membranes indicate that the oscillation can occur even in the absence of the channel protein. The oscillations at artificial membranes are expected to provide fundamental information useful in elucidating the oscillation processes in living membrane systems. Since the oscillations may be attributed to the coupling occurring among interfacial charge transfer, interfacial adsorption, mass transfer, and chemical reactions, the processes are presumed to be simpler than the oscillation in biomembranes. Even in artificial oscillation systems, elementary reactions for the oscillation which have been verified experimentally are very few. [Pg.609]

Although no exact correlation between experiment and model was produced by this exercise, it has been shown that the two polymers studied exhibit phase-separated morphologies that are similar in nature to the extent that they are subject to nearly identical polarizations. The large polarizations measured can only be explained by high interfacial areas, congruent with semicrystalline lamellar morphologies. Finally, the divergence of the observed polarizations from those predicted by the two-phase model is quite likely due to the existence of finite-thickness, transition zones between dissimilar domains. [Pg.290]

Figure 8 shows the time evolution of interfacial thickness for the PS/dPS bilayer as a function of temperature [40]. The of both PS and dPS was fixed at 29k. The interfacial characterization was made by dynamic secondary ion mass spectroscopy (DSIMS). In the case of aimealing at 400, 393, and 380 K (i.e., above the 7 of 376 K), the interfacial thickness proportionally increased to a half power of the annealing time. This is in good accordance with the context of Fickian diffusion. By contrast, a unique interfacial evolution was observed at 370 K (i.e., between 7 and T ). At first, the bilayer interface monotonically thickened with increasing time,... [Pg.10]

Taking into consideration of both surface effect and interfacial effect we can understand the decrease in thermal expansivity and Tg with decreasing thickness observed simultaneously for the same PS thin film without inconsistency. [Pg.137]

Figure 10 shows a three dimensional plot of the Si 2p spectrum as a function of silicon dioxide film thickness obtained by sequentially etching a 250 A thick oxide with HF/ethanol (34). Monochromatic Al k-a x-rays were used to excite the spectra in a standard XPS system. Notice that the Si 2p component due to the substrate is observed at about 100 A from the interface because the escape depth is about 38 A for 1386 eV electrons (32). Suboxides at the interface begin to appear as a prominent shift in the 2p components at about 20 A and are present up to the Si surface. Grunthaner, et al. (34) showed that the interfacial region consists of approximately 1 monolayer of Si,0, SiO and Si,0, in a 2 3 2... [Pg.81]

The XRD studies of the interfacial transition zone (material produced by abrasion of paste layers) [16], as well as the SEM observations with EDS analysis [16] revealed the presence of transition zone surrounding the aggregate grains, determined by Maso as an aureole [ 10]. This relates to the former water film around the aggregate. This area shows higher w/c ratio and subsequently cement components can readily dissolve, as well as the hydration products crystallize from the solution. Calcium hydroxide crystallizes in this interfacial transition zone and the crystals are oriented in such a way that their (001) axis is perpendicular to the surface of aggregate, as it was reported by Barnes et al. [17]. The C-S-H is then formed and the two products occur together as a duplex film about 1 pm thick (Fig. 6.7). [Pg.376]

In Figure 2.20, the experimental [110,111] surface tensions of the 1-propanol + n-hexane mixture at 298.15 K with the predicted ones by the present combined model are compared. In view of the strong nonideality of this system, the agreement is again rather satisfactory. For the same system, we have calculated the interfacial layer thickness as a function of composition of the liquid phase. The calculations are shown in Figure 2.21. This is an azeotropic system, and it is worth observing that the calculated maximum in Figure 2.21 is close to the azeotropic composition. In Ref. [106], we have shown that the interfacial layer thickness increases with the vapor pressure of the system. [Pg.182]

Gardon(35,36) has determined the peeling force and the mode of separation as a function of separation rate and of adhesive thickness, for cellophane films bonded together by an acrylic adhesive. He found a transition from cohesive separation to mixed or interfacial separation, with increasing crosshead speed and with decreasing thickness of the adhesive layer. A transition from cohesive to mixed or adhesive failure was also observed with decreasing temperature. These observations are in exact agreement with the predictions that we have just indicated above. Similar results have been reported by Kaelble.(i3,34)... [Pg.64]


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Interfacial thickness

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