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F-RD surface

Figure 1.28. Left one node of the F-RD surface. Right The other node of the F-RD surface. Figure 1.28. Left one node of the F-RD surface. Right The other node of the F-RD surface.
The surfaces in Fig. 4(d,e,f,) obtained from the functional (1) are the surfaces already discovered by Schoen [28] and named by him O, C-TO, I-WP, F-RD. O, C-TO is the only structure which cannot be minimized with respect to the cell length. For all the structures except this one we are able to find the minimal cell length i.e., by varying the cell length we are able to find the length for which the free energy per unit volume (functional (1)) has a minimum. The O, C-TO structure collapses to I-WP when the cell... [Pg.705]

We suspect that the exact analytical value for the dimensionless area of an L-F region of the F-RD minimal surface is 3K k)/K k ) where... [Pg.378]

K k)/K k ) is due to Schoen (1970), who adapted a result of Schwarz (1890), and the work of Stessmann (1934) shows that the same formula applies to the F-RD minimal surface. Stessmann s analysis was not complete enough to yield the modulus k, but by Schwarz s work it is known that k =(fl2 — 3) where a, a2,a3 are roots (in descending order) to... [Pg.379]

Many important questions and conjectures remain unresolved. It is not known whether these solutions are the only embedded //-surfaces for the five dual pairs of skeletal graphs studied, for example. An important issue is whether or not there exists a bound on the mean curvature attainable in such families for all of the branches studied here, and for the family of unduloids with a fixed repeat distance (Anderson 1986), the dimensionless mean curvature H = HX is always less than n, where X is the sphere diameter in the sphere-pack limit. It is possible that there exists an upper bound on H lower than n that depends on the coordination number, or the Euler characteristic. For the P, D, I, WP, F, and RD branches, the islands over which K > 0 coalesce wih neighboring R regions at a critical mean curvature that is the same (to within an error in H of about 0.15) as the value H corresponding to the local minimum in surface area. We have given what we suspect to be the analytical value for the area of the F-RD minimal surfaces, and for the first nonzero coefficient in both the area and volume expansions about // = 0 in the P family. [Pg.391]

The I-WP and F-RD minimal surfaces have been shown to provide two counterexamples to a conjecture that has previously been made (Meeks 1978, p. 81, Conjecture 6) A triply periodic minimal surface disconnects into two regions with asymptotically the same volume. The volume fraction of the labyrinth containing the symmetric skeletal graph is 0.5360 0.0002 for the I-WP minimal surface and 0.5319 0.0001 for F-RD. [Pg.392]

Figure 6a. The F-RD minimal surface. One lattice-fundamental region is shown. Space group is Fw3m and the Euler characteristic per lattice-fundamental region is — 10. The twelve necks are orthogonal to the twelve faces of the rhombic dodecahedron outlined by the red skeletal graph. Figure 6a. The F-RD minimal surface. One lattice-fundamental region is shown. Space group is Fw3m and the Euler characteristic per lattice-fundamental region is — 10. The twelve necks are orthogonal to the twelve faces of the rhombic dodecahedron outlined by the red skeletal graph.
Figure 6c. Solution with H = 2.5, same space group and topological type as the F-RD minimal surface. Figure 6c. Solution with H = 2.5, same space group and topological type as the F-RD minimal surface.
It is not irrelevant whether the charge transfer proceeds via the adsorbed or via the non-adsorbed species, because a model is needed to give eqn. (166g) an explicit formulation. As we have seen in Sect. 4, a non-linear multi-step mechanism may lead eventually to rather complex expressions of v — f(E, cD, cR ). If the reaction is supposed to proceed via adsorbed O and R, similar or even heavier complexity can be expected, depending on the nature of the isotherms. In that case, the formulation in terms of surface excesses, i.e. v = f(E, rD, PR ) may be advantageous. [Pg.310]

Case II of Fig. 1 shows the cross-section of a pit formed by a preferential etch at a dislocation on a material whose planes form closed figures, such as the cubic system or the pyramidal planes of the hexagonal system. The relative etch rates are Rd > Ra > Ry F°r example, if the dislocation is normal to a 111 surface, triangular pyramidal pits will be formed. These pits have smooth, rather than terraced, sides as shown in Fig. 3. If, however, the dislocation line is at an angle to a ill surface, the triangular pyramidal pit is lopsided (Fig. [Pg.158]

Rodliffe, R.S. and Means, F.A., 1979, Factors Governing Particulate Corrosion Product Adhesion to Surfaces in Water Reactor Coolant Circuits. Report CEGB RD/B/N4525. [Pg.95]

Koningsberger DC, Prins R (eds) (1988) X-ray absorption Principles, applications, techniques of EXAFS, SEXAFS, and XANES. John Wiley Sons, New York Lindle DW, Cowan PL, Jach T, LaVilla RE, Deslattes RD, Perera RCC (1991) Polarized X-ray emission studies of methyl chloride and chlorofluoromethanes. Phys Rev A 43 2353-2362 Loo BW, Sauerwald IM, Hitchcock AP, Rothman SS (2001) A new sample preparation method for biological soft X-ray microscopy nitrogen based contrast and radiation tolerance properties of glycol methacrylate-embedded and sectioned tissue. J Microsc 204 69-86 Matsui F, Yeom HW, Matsuda I, Ohta T (2000) Adsorption and reaction of acetylene and ethylene on the Si(001)2xl surface. Phys Rev 62 5036-5044... [Pg.553]

Balbach JJ, Ishii Y, Antzutkin ON, Leapman RD, Rizzo NW, Dyda F, Reed J, Tycko R (2000) Amyloid fibril formation by A beta 16-22, a seven-residue fragment of the Alzheima- s beta-amyloid peptide, and structural characterization by solid state NMR. Biochemistry 39 13748-13759 Bamberger ME, Harris ME, McDonald DR, Husemann J, Landreth GE (2003) A cell surface receptor complex for fibrillar beta-amyloid mediates microglial activation. J Neurosci 23 2665-2674 Baskakov IV, Legname G, Baldwin MA, Prusiner SB, Cohen FE (2002) Pathway complexity of prion protein assembly into amyloid. J Biol Chem 277 21140-21148 Baxa U, Cheng N, Winkler DC, Chiu TK, Davies DR, Sharma D, Inouye H, Kirschner DA, Wickner RB, Steven AC (2005) Filaments of the Ure2p prion protein have a cross-beta core structure. J Stmet Biol 150 170-179... [Pg.60]

Figure 3 (A) Schematic view of a PIXE chamber. Key 1, diaphragms to collimate the beam 2, carousel for the samples 3, lifting mechanism to position the sample in front of the beam 4, sample holders 5, X-ray detector 6, wheel with different absorbers to filter out low-energy X-rays 7, y-detector 8, protractor to position a surface barrier detector. (B) Photograph of a typical PIXE environment with a pelletron accelerator and micro- and macro-PIXE beam lines. (Reprinted with permission from Vis RD, Kramer JLAM, van Langevelde F, and Mars L (1993) The upgraded Amsterdam nuclear microprobe. Physics Review B Nuclear Instrument Methods BTI 41-44 Elsevier.)... Figure 3 (A) Schematic view of a PIXE chamber. Key 1, diaphragms to collimate the beam 2, carousel for the samples 3, lifting mechanism to position the sample in front of the beam 4, sample holders 5, X-ray detector 6, wheel with different absorbers to filter out low-energy X-rays 7, y-detector 8, protractor to position a surface barrier detector. (B) Photograph of a typical PIXE environment with a pelletron accelerator and micro- and macro-PIXE beam lines. (Reprinted with permission from Vis RD, Kramer JLAM, van Langevelde F, and Mars L (1993) The upgraded Amsterdam nuclear microprobe. Physics Review B Nuclear Instrument Methods BTI 41-44 Elsevier.)...
Wu S-F, Johnson BR, Levine RD (1973) Quantum mechanical computational studies of chemical reactions III. CoUinear A BC reaction with some model potential energy surfaces. Mol Phys 25 839-856... [Pg.75]

Other surfaces, typically platinum, show pH-dependent processes which have been variously explained. Damjanovic and Brusic believe that the rds is similar to reaction (93) under Temkin conditions, with a Tafel slope or RT/F ... [Pg.231]


See other pages where F-RD surface is mentioned: [Pg.161]    [Pg.151]    [Pg.316]    [Pg.161]    [Pg.151]    [Pg.316]    [Pg.706]    [Pg.316]    [Pg.339]    [Pg.345]    [Pg.346]    [Pg.360]    [Pg.379]    [Pg.384]    [Pg.375]    [Pg.375]    [Pg.376]    [Pg.377]    [Pg.378]    [Pg.313]    [Pg.245]    [Pg.115]    [Pg.29]    [Pg.173]    [Pg.190]    [Pg.52]    [Pg.50]    [Pg.364]    [Pg.376]    [Pg.10]    [Pg.425]    [Pg.135]    [Pg.711]    [Pg.267]    [Pg.170]   
See also in sourсe #XX -- [ Pg.38 ]




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