Chevron pattern

Close examination of these areas under a low-power microscope revealed smoothly rippled, spherical surfaces in the weld region and a chevron pattern that pointed back to the weld in the plate. Cross sections cut through the weld revealed substantial subsurface porosity and regions where oxidized surfaces prevented metallurgical bonding of the weld (Fig. 

Compared with traditional plate-and-frame exchangers, this design relies on a more loosely corrugated chevron pattern, which provides exceptional resistance to clogging. The plates are designed with few, if any, contact points between adjacent plates to trap fibers or solids. Some styles of this exchanger use wide-gap plates on the process side and conventional chevron patterns on the coolant... 

Figure 7.79 Fracture surface shows convergent chevron patterns as the fracture initiation site.1 (Reprinted with the permission of M. Zamanzadeh, ATCO Associates, Pittsburgh, USA)...

FIGURE 6.36 Two types of plates for the gasketed-plate heat exchanger (a) paraUel-corrugated plate (b) cross-corrugated plate ( herringbone or chevron pattern). 

Chevrons (Chevron halite) Halite crystal, which is grown on a basin floor from evaporating brine. It is characterized by enclosed solid, liqnid, or vapor inclusions arranged in a chevron pattern. 

Fig. 3.10.2. Electrohydrodynamic alignment patterns in nematic liquid crystals, (a) Williams domains in a 38 //m thick sample of p-azoxyanisole. 7.8 V, 100 Hz. (Penz. ) (Z>) Chevron pattern of oscillating domains in MBBA. Sample thickness 100 fjm. Distance between bright lines 5 /im. 260 V, 120 Hz. (Orsay Liquid...

Failure of a Landing Gear Steel Pin A landing gear pin failure occurred in the cylindrical part of the pin whose outer surface was corroded (Sastri et al. (19), p. 515, Fig. 7.78). The fracture surface with convergent chevron patterns at the initiation site and a cover of corrosion product on the surface is shown in Sastri et al. (19, p. 516, Fig. 7.80). Corrosion pits were present at the exterior surface of the cylindrical pin. Pitting corrosion was also present at the fracture initiation site. 

Directing Convection Marangoni Convection/ Evaporation/Self- assembly Coffee rings, polygonal network structures, fingering instabilities, cracks, chevron patterns, etc. Nanometer to micrometer Marangoni convection and stick-slip motion can determine the final patterns observed [132-134]... 

FIGURE 5.10. Electrohydrodynamic instabilities in nematic liquid crystal with homogeneous initial orientation in the high-frequency regime (a > lJc)- (a) Domains when the voltage is slightly above the threshold voltage and (b) the Chevron pattern. 

Many investigations were devoted to the description of different types of misalignment in FLCs, such as the appearance of zig-zag defects [145], various twisted states [146], focal conics [147], field line defects [148], etc. Optical properties [149] and X-ray diffraction [150] by chevron patterns were studied. Chevrons were presented as soliton defects [151] of an FLC director field. 

Figure 3.11 Lamellar block copolymer deformed In direction perpendicular to the lamellae orientation, resulting In the formation of a chevron pattern deformation direction shown by an arrow the butadiene lamellae are stained dark by OSO4...

Four columns or legs supporting the Citicorp Center s frame are positioned at the middle of each side of the building. LeMessurier designed a unique system of V-shaped wind braces on each facade, arranged in a chevron pattern, to transfer loads to the column. Construction of the Citicorp Center was completed in 1977. 

The optical pattern of the perturbed state in the high frequency (/>/,) region is characterized by periodic parallel striations of a much shorter period (a few micrometers) than the Williams domains [23]. Above the threshold, these striations move, and bend and give rise to what has been called a chevron pattern (Fig. 5) [8-12,17,23-26]. In this regime, the threshold is determined by a critical field rather than a critical voltage. The threshold field strength increases with the square root of the frequency. The spatial periodicity of the chevron pattern is also frequency dependent it is... 

Figure 11(a) shows a typical RHEED pattern of a HVPEl sample annealed at 600°C for 20 min after the three-step annealing. We can see characteristic "chevrons" in the RHEED patterns, corresponding to facets, in addition to transmission spots from 3D GaN islands. The transmission spot intensities were weak, indicating a small number of epitaxial islands. The chevron patterns were broad, indicating small domains. Although the chevron directions are (1124) at the [1100] incidence (Fig. 6(a)), we consider that these are part of (1012) reciprocal rods, which correspond to 1012 facets, from the LEED results of Fig. 11(b). Figures 11(b) and... 

A fractographic pattern of radial marks (shear ledges) that look like nested letter V s sometimes called a herringbone pattern. Chevron patterns are typically found on brittle fracture surfaces in parts whose widths are considerably greater than their thicknesses. The points of the chevrons can be traced back to the fracture origin. 

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