Elongation planar

Small-amplitude oscillatory shear Uniaxial steady elongation Biaxial steady elongation Planar steady elongation Elongational stress growth... 

Antidrcular development is very rarely applied in planar chromatographic practice for preparative separation. This mode of separation was introduced by Kaiser [40]. Studer and Traitler adapted the antidrcular U-chamber from CAMAG to preparative separations on 20 x20 cm plates [22], as mentioned earher. The sample mixture was spotted at the circumference of the plate, and the mobile phase was moved from the circumference to the center of the plate. The bands obtained are elongated, but their diameter measured perpendicular to the direction of mobile phase movement... 

In the case of r)2-coordination of the exocyclic C=C bond, it becomes substantially elongated compared with the double bond of free alkenes, as a result of back donation from the metal to the 7t orbitals of the double bond. For instance, in complex 17b the coordinated bond length is 1.437 A (see Fig. 3.2).18 This is also reflected in the loss of planarity around the quaternary exocyclic carbon, the methylenic carbon being bent out of the ring plane by 10.78°.18 Similar structural features were also observed with other P2Pd conjugated olefin complexes.39... 

Finally we will consider the two flow fields that yield extensional deformation. The first is axial elongational in which the fluid is contained between two planar surfaces in relative motion along their planar normals. With the axial extension direction taken as z, one has nzz = e = —2nxx = —2xyy and... 

The degree of deformation and whether or not a drop breaks is completely determined by Ca, p, the flow type, and the initial drop shape and orientation. If Ca is less than a critical value, Cacri the initially spherical drop is deformed into a stable ellipsoid. If Ca is greater than Cacrit, a stable drop shape does not exist, so the drop will be continually stretched until it breaks. For linear, steady flows, the critical capillary number, Cacrit, is a function of the flow type and p. Figure 14 shows the dependence of CaCTi, on p for flows between elongational flow and simple shear flow. Bentley and Leal (1986) have shown that for flows with vorticity between simple shear flow and planar elongational flow, Caen, lies between the two curves in Fig. 14. The important points to be noted from Fig. 14 are these ... 

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