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Surfaces perpendicular

The combination of items (4) and (5) leads to the important conclusion that light intensity is the measure of the flux of energy through a surface perpendicular to the direction of propagation-the yz plane in our convention-and this is proportional to E. ... [Pg.665]

A vertical CVD reactor (cf. Figure lb) consists of an axlsymmetrlc enclosure with the deposition surface perpendicular to the Incoming gas stream. The reactant gases are typically Introduced at the top and fiow down towards the heated susceptor. Thus, the least dense gas Is closest to the growth Interface which destabilizes the fiow. The result Is recirculation cells which Introduce not only film thickness and composition variations but also broaden Junctions between layers. This Is particularly of... [Pg.362]

In the case of t < Lo, it has been suggested that perpendicular lamellae are favored in the boundary-symmetric confined film because they avoid the entropic penalty associated with the compressed chain conformations in parallel-oriented microdomains [109]. In boundary-asymmetric substrate-supported films, various kinds of morphologies, including hybrid morphologies that combine surface-parallel and surface-perpendicular components, are predicted, as well as observed, depending on the film thickness difference and surface/interface energies [14,41,120]. [Pg.204]

Fig. 5 Schematic cross-sections of thin film morphologies of the topographic pattern grown by a graphoepitaxy method. A micropattern with different lamellar domain orientation is shown, a Surface-parallel lamellae, typical of film thickness t greater than the natural equilibrium period Lq. b Surface-perpendicular lamellae, typical of film thickness t less than L0. (adapted from [41])... Fig. 5 Schematic cross-sections of thin film morphologies of the topographic pattern grown by a graphoepitaxy method. A micropattern with different lamellar domain orientation is shown, a Surface-parallel lamellae, typical of film thickness t greater than the natural equilibrium period Lq. b Surface-perpendicular lamellae, typical of film thickness t less than L0. (adapted from [41])...
Let us consider a medium moving with velocity v (components vx, Vy, vz). A medium with non-zero velocity is said to be advective. Let us first define in the most general way the flux of volume at a point M of the familiar 3D space this is simply the quantity of volume moving across the unit surface perpendicular to v per unit time. For an arbitrary surface 6S next to M and perpendicular to v (Figure 8.1) and during time dt, the volume will be... [Pg.401]

Figure 8.1 For a surface perpendicular to the displacement, the flux of volume through the element of surface 8S during the infinitesimal time interval dt is the vector v8Sdt. v therefore is the flux of volume crossing the unit surface per unit time. Figure 8.1 For a surface perpendicular to the displacement, the flux of volume through the element of surface 8S during the infinitesimal time interval dt is the vector v8Sdt. v therefore is the flux of volume crossing the unit surface per unit time.
The balance of material in the x direction is the difference between the fluxes through the surfaces perpendicular to the x axis (Figure 8.3). This corresponds to the difference... [Pg.404]

It is obvious that the entropy change will be positive in the region Mi > 1 and negative in the region Mi < 1 for gases with 1 < y < 1-67. Thus, Eq. (1.46) is valid only when Ml is greater than unity. In other words, a discontinuous flow is formed only when Ml > 1. This discontinuous surface perpendicular to the flow direction is the normal shock wave. The downstream Mach number, Mj, is always < 1, i. e. subsonic flow, and the stagnation pressure ratio is obtained as a function of Mi by Eqs. (1.37) and (1.41). The ratios of temperature, pressure, and density across the shock wave are obtained as a function of Mi by the use of Eqs. (1.38)-(1.40) and Eqs. (1.25)-(1.27). The characteristics of a normal shock wave are summarized as follows ... [Pg.11]

In another example, the adsorption of surfactants on polycarbonate indicated that, depending on the surfactant and concentration, the adsorbed molecules might be lying flat on the surface perpendicular to it, or might form a bilayer. [Pg.122]

Consider a finite crystal of thickness L, along the ith axis, as sketched in Figure 1.7. Let c, be the surface free energy per unit area of surfaces perpendicular to the ith axis. [Pg.14]

The element ryl of the second-order stress tensor t is the force-per-unit area acting in the x direction on an elemental fluid surface perpendicular to the y direction. The stress tensor is symmetric, and so ryx = tiv. [Pg.161]

When a jet of fluid submerged in a medium of that fluid strikes a surface perpendicularly, it spreads out radially over that surface. Original interest in these systems was due to mass transfer investigations of downward directed jets of vertical-take-off aircraft [41], though other applications such as electrochemical machining are important. [Pg.373]

B) US Bullet Impact MetbodfModification). According to Stein Pollack(Ref 16,p 1), the nipple bomb described above is not very satisfactory because the bullet strikes the curved surface thereby introducing undesirable variables which are inherent in a curved surface. To eliminate this problem a new bomb was designed which presents a flat surface perpendicular to the line of fire. This new bomb, however, retains a major deficiency of impact testing in that the explosive reaction is only described qualitatively in terms of detonation complete or incomplete), burning, smoke,or unaffected. The new bomb consist s of a metal cylinder 3 long and 2 diam. The ends of the bomb are closed... [Pg.333]

The surface of bulk block copolymer samples has been studied using TEM by Turturro et al. (1995). They report that non-equilibrium structures with lamellar and cylindrical microdomains oriented normal to the free surface can result from solvent casting, with a high evaporation rate. However, slower evaporation of solvent from their PS-PB diblocks resulted in the equilibrium conformation with domains parallel to the free surface. Perpendicular orientation of PS-PB lamellae at the free surface was observed earlier by Henkee et al. (1988) who studied thin films prepared by solvent casting. They observed that a reduction of this orientation occurs in favour of the parallel one on annealing the sample. [Pg.114]

The formalism of the reciprocal lattice and the Ewald construction can be applied to the diffraction at surfaces. As an example, we consider how the diffraction pattern of a LEED experiment (see Fig. 8.21) results from the surface structure. The most simple case is an experiment where the electron beam hits the crystal surface perpendicularly as shown in Fig. A.5. Since we do not have a Laue condition to fulfill in the direction normal to the surface, we get rods vertical to the surface instead of single points. All intersecting points between these rods and the Ewald sphere will lead to diffraction peaks. Therefore, we always observe diffraction... [Pg.325]

Fig. 47. Height (top) and phase (bottom) images of a microlayered PE sample recorded on the surface perpendicular to the layer plane using A0= 100 nm a light tapping (rsp=0.8—0.9) b moderate tapping (rsp=0.4-0.7) and chard tapping (rsp=0.1-0.3). In all height images the contrast covers variations in the 0-170 nm range. In the phase images, the contrast covers phase shifts in the 20° (a,b) and 50° in (c). Reproduced from [110]... Fig. 47. Height (top) and phase (bottom) images of a microlayered PE sample recorded on the surface perpendicular to the layer plane using A0= 100 nm a light tapping (rsp=0.8—0.9) b moderate tapping (rsp=0.4-0.7) and chard tapping (rsp=0.1-0.3). In all height images the contrast covers variations in the 0-170 nm range. In the phase images, the contrast covers phase shifts in the 20° (a,b) and 50° in (c). Reproduced from [110]...

See other pages where Surfaces perpendicular is mentioned: [Pg.412]    [Pg.128]    [Pg.874]    [Pg.412]    [Pg.1051]    [Pg.189]    [Pg.46]    [Pg.104]    [Pg.60]    [Pg.7]    [Pg.106]    [Pg.63]    [Pg.38]    [Pg.207]    [Pg.208]    [Pg.452]    [Pg.185]    [Pg.69]    [Pg.209]    [Pg.188]    [Pg.73]    [Pg.153]    [Pg.62]    [Pg.285]    [Pg.8]    [Pg.419]    [Pg.104]    [Pg.197]    [Pg.30]    [Pg.10]    [Pg.201]    [Pg.196]    [Pg.197]   
See also in sourсe #XX -- [ Pg.207 ]




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