Herringbone

Signals from the notch tip can only be identified for the herringbone grain structure and not for the perpendicular one. 

Figure 6 Slowness and group velocity diagrams for austenitic weld material herringbone grain orientation...

Figure S V-butt weld with herringbone grain orientation and an inclination of the interface of 15° left without, right with backwall breaking notch...

Travel time The larger group velocity for herringbone grain orientation (see Fig. 6(b)) explains the shorter travel time (see A-scans in Fig. 7 and 8). 

Notch tip With perpendicular grain orientation no notch tips are detected. The snapshots (see Fig. 7 second and third snapshot from top on the right) show that in the direction to the receiver there is a gap in the reflected / diffracted quasi shear wavefront. In contrast, the notch tips can be detected within the herringbone structure. 

This region has been divided into two subphases, L and S. The L phase differs from the L2 phase in the direction of tilt. Molecules tilt toward their nearest neighbors in L2 and toward next nearest neighbors in L (a smectic F phase). The S phase comprises the higher-ir and lower-T part of L2. This phase is characterized by smectic H or a tilted herringbone structure and there are two molecules (of different orientation) in the unit cell. Another phase having a different tilt direction, L, can appear between the L2 and L 2 phases. A new phase has been identified in the L 2 domain. It is probably a smectic L structure of different azimuthal tilt than L2 [185]. 

S. Chains in the S phase are also oriented normal to the surface, yet the unit cell is rectangular possibly because of restricted rotation. This structure is characterized as the smectic E or herringbone phase. Schofield and Rice [204] applied a lattice density functional theory to describe the second-order rotator (LS)-heiTingbone (S) phase transition. 

Packing of the cyclodexthn molecules (a, P, P) within the crystal lattice of iaclusion compounds (58,59) occurs in one of two modes, described as cage and channel stmctures (Fig. 7). In channel-type inclusions, cyclodextrin molecules are stacked on top of one another like coins in a roU producing endless channels in which guest molecules are embedded (Fig. 7a). In crystal stmctures of the cage type, the cavity of one cyclodextrin molecule is blocked off on both sides by neighboring cyclodextrin molecules packed crosswise in herringbone fashion (Fig. 7b), or in a motif reminiscent of bricks in a wall (Fig. 7c). 

Fig. 7. Schemes of crystalline cyclodextrin inclusion compounds (a) channel type (b) cage herringbone type (c) cage brick type (58).

LB films of 1,4,8,11,15,18-hexaoctyl-22,25-bis-(carboxypropyl)-phthalocyanine (2), an asymmetrically substituted phthalocyanine, were stable monolayers formed at the water—air interface that could be transferred onto hydrophilic siUca substrates (32—34). When a monolayer film of the phthalocyanine derivative was heated, there was a remarkable change in the optical spectmm. This, by comparison to the spectmm of the bulk material, indicated a phase transition from the low temperature herringbone packing, to a high temperature hexagonal packing. 

AGMA 211.02, Surface Durability (Pitting) of Helical and Herringbone Gear Teeth, Washington, D.C., 1969. 

Next consider the wavy plate with herringbone waves. This arrangement with the relevant geometrical parameters is shown in Fig. 9.13. 

The heat transfer coefficient for a herringbone plate is calculated from ... 

Phase transitions in two-dimensional layers often have very interesting and surprising features. The phase diagram of the multicomponent Widom-Rowhnson model with purely repulsive interactions contains a nontrivial phase where only one of the sublattices is preferentially occupied. Fluids and molecules adsorbed on substrate surfaces often have phase transitions at low temperatures where quantum effects have to be considered. Examples are molecular layers of H2, D2, N2 and CO molecules on graphite substrates. We review the path integral Monte Carlo (PIMC) approach to such phenomena, clarify certain experimentally observed anomalies in H2 and D2 layers, and give predictions for the order of the N2 herringbone transition. Dynamical quantum phenomena in fluids are analyzed via PIMC as well. Comparisons with the results of approximate analytical theories demonstrate the importance of the PIMC approach to phase transitions where quantum effects play a role. 

Linear N2 molecules adsorbed on graphite show a transition from a high-temperature phase with orientational disorder to a low-temperature phase with herringbone ordering of the orientational degrees of freedom (see Sec. lie and Fig. 11). 

In interesting studies [322] of the order of the N2 herringbone transition on graphite, the APR Hamiltonian [155]... 

FIG. 11 Schematic configurations of N2 molecules on a graphite substrate (p = pyj) for temperatures above the herringbone transition temperature (a) and below it (b). 

Furthermore, one can infer quantitatively from the data in Fig. 13 that the quantum system cannot reach the maximum herringbone ordering even at extremely low temperatures the quantum hbrations depress the saturation value by 10%. In Fig. 13, the order parameter and total energy as obtained from the full quantum simulation are compared with standard approximate theories valid for low and high temperatures. One can clearly see how the quasi classical Feynman-Hibbs curve matches the exact quantum data above 30 K. However, just below the phase transition, this second-order approximation in the quantum fluctuations fails and yields uncontrolled estimates just below the point of failure it gives classical values for the order parameter and the herringbone ordering even vanishes below... 

FIG. 13 Herringbone order parameter and total energy for N2 (X model with Steele s corrugation). Quantum simulation, full line classical simulation, dotted line quasiharmonic theory, dashed line Feynman-Hibbs simulation, triangles. The lines are linear connections of the data. (Reprinted with permission from Ref. 95, Fig. 4. 1993, American Physical Society.)... 

Wound type Herringbone, High through-put or Low Density 13—14 120 44- 99.94- For very high efficency For services containing solids, or... 

Helical, double (also referred to as herringbone) Connects parallel shafts, overcomes high-end thrust present in single-helical gears, compact, quiet and smooth operation at higher speeds (1000 to 12,000 fpm or higher), high efficiencies ... 

The double-helical gear, also referred to as the herringbone gear (Figure 39.8), is used for transmitting power... 

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