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Interfaces interior surfaces

The interior surfaces of the low-alloy steel portions of the PWR RPV, closure head and flange area are typically clad with corrosion-resistant material to prevent general corrosion of the materials by borated reactor coolant. BWR RPVs were clad below the level of the steam-water interface. The top head of the BWR RPV is usually not clad because the steam separators and dryers scrub the liquid out of the steam vapor before it... [Pg.19]

S is the distance between the semiconductor surface and the reaction plane at OHP, and Np(x = 0) is the number of photoexcited minority carriers per unit volume in the surface region of the semiconductor which arrive from the interior of the semiconductor to this region. f E, hv) is the Fermi distribution of photoexcited minority carrier. This quantity, Np x = 0), depends on the intensity, energy, and absorption coefficient of incident light, diffusion length of electron in the semiconductor, and its band gap, etc. Furthermore, it depends on the charge transfer phenomena and the surface recombination rate at the interface. The surface recombination rate constant depends on the induced density of surface states due to adsorbed anions at the electrodesolution interface. The recombination rate constant can be expressed as... [Pg.65]

New additives based on fluoropolymers have been introduced by DuPont and by Dyneon, to promote free flowing in polyolefins for extrusion and blown film production. They appear to act by coating the interior surface of the extrusion die with a microscopically thin non-stick film, which reduces friction at the resin/die interface and allows the extrusion compound to flow freely and more rapidly through the die opening. The non-stick properties also prevent accumulation of resin particles at the exit of the die, so eliminating the major cause of die build-up. The coating is continuously renewed by the additive through the extrusion process. [Pg.202]

Research is in progress to use electron spin resonance (ESR) to characterize the interior surfaces in composites. Spin probes are to be deposited near the interface of a fiber/polymer matrix composite, and ESR is to be used to monitor the local orientation of the spin probes. The goal is to assess the spatial range of the interphase and to understand how the mechanical load is transferred from the fiber to the matrix. [Pg.30]

Since solids do not exist as truly infinite systems, there are issues related to their temiination (i.e. surfaces). However, in most cases, the existence of a surface does not strongly affect the properties of the crystal as a whole. The number of atoms in the interior of a cluster scale as the cube of the size of the specimen while the number of surface atoms scale as the square of the size of the specimen. For a sample of macroscopic size, the number of interior atoms vastly exceeds the number of atoms at the surface. On the other hand, there are interesting properties of the surface of condensed matter systems that have no analogue in atomic or molecular systems. For example, electronic states can exist that trap electrons at the interface between a solid and the vacuum [1]. [Pg.86]

The atoms and molecules at the interface between a Hquid (or soHd) and a vacuum are attracted more strongly toward the interior than toward the vacuum. The material parameter used to characterize this imbalance is the interfacial energy density y, usually called surface tension. It is highest for metals (<1 J/m ) (1 J/m = N/m), moderate for metal oxides (<0.1 J/m ), and lowest for hydrocarbons and fluorocarbons (0.02 J /m minimum) (4). The International Standards Organization describes weU-estabHshed methods for determining surface tension, eg, ISO 304 for Hquids containing surfactants and ISO 6889 for two-Hquid systems containing surfactants. [Pg.541]

Yet another strength of SNMS is the ability to measure elemental concentrations accurately at interfaces, as illustrated in Figure 8, which shows the results of the measurement of N and O in a Ti thin film on Si. A substantial oxide film has formed on the exposed Ti surface. The interior of the Ti film is free of N and O, but significant amounts of both are observed at the Ti/Si interface. SNMS is as sensitive to O as to N, and both the O and N contents are quantitatively measured in all regions of the structure, including the interface regions. Quantitation at the interface transition between two matrix types is difficult for SIMS due to the matrix dependence of ion yields. [Pg.583]

Fig. 10 shows the radial particle densities, electrolyte solutions in nonpolar pores. Fig. 11 the corresponding data for electrolyte solutions in functionalized pores with immobile point charges on the cylinder surface. All ion density profiles in the nonpolar pores show a clear preference for the interior of the pore. The ions avoid the pore surface, a consequence of the tendency to form complete hydration shells. The ionic distribution is analogous to the one of electrolytes near planar nonpolar surfaces or near the liquid/gas interface (vide supra). [Pg.370]

The subunits of an oligomeric protein typically fold into apparently independent globular conformations and then interact with other subunits. The particular surfaces at which protein subunits interact are similar in nature to the interiors of the individual subunits. These interfaces are closely packed and involve both polar and hydrophobic interactions. Interacting surfaces must therefore possess complementary arrangements of polar and hydrophobic groups. [Pg.201]

At the end of the 1960s, Subba Rao et al. examined the influence of the interface on the CMC values [56]. They found a decrease in the CMC at the oil-water interface compared with the air-water interface. The CMC decreased by about 10% in the presence of heptane and by about 30-40% in the presence of benzene. The solubilization of the hydrocarbon in the micelle interior results in an increase in the micelle size and a slight change in the curvature of the micelle surface. The electrical potential and hence the electrical work of... [Pg.471]

Different structural models of the ionic EDL have been suggested in order to describe the electrical properties of interfaces. Consider the distribution of electrostatic potential j/ at the solution side of the ionic EDL as a function of distance X from the surface. By convention we locate the point of reference in the solution interior (i.e., we shall assume that / = 0 when x->°°). The potential at X = 0 will be designated as rj/g. The sign of parameter /o corresponds to that of Qs,m-... [Pg.150]

Maa (M2) developed a procedure for calculating the liquid surface temperature as a function of the time each liquid element is in contact with the vapor. He assumed that the latent heat of vaporization is transferred from the interior of the liquid to the interface by pure conduction. Consequently, the sole source of energy for vaporization is the sensible heat made available by a change in the liquid temperature. If exposure time is short, only the liquid near the surface will undergo a temperature change. The heat transfer within the liquid is modeled by... [Pg.356]


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See also in sourсe #XX -- [ Pg.640 , Pg.641 , Pg.642 , Pg.643 ]




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Interior

Surface interface

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