Longitudinal elongation

Figure 14. Fiber loading vs. longitudinal elongation at break for various fibers...

Apart from the longitudinal elongation (r) (parallel to/) it is of interest to ascertain the lateral spread of the chain in strong elongation. The projection of the string of blobs on a plane normal to f is an ideal string, and thus... 

It can be concluded, that various approach exist which can be used to control the inhomogeneity of the mechanical field in various equipment (Fig. 9,a and Fig. 9,e) rotation of clamps between 0cross-sectional compression (Fig. 9,b) can also be used. In the device shown in Fig. 9,d the deformation is one of longitudinal elongation. The additional variation of the mechanical field inhomogeneity is possible by the use of clamps with any configuration [12]. 

Poisson s Ration n (for S. Poisson symbol p or v) In a material under tensile stress, the ratio of the transverse contraction to the longitudinal elongation. For metals, Poisson s ratio is bout 0.3, for concrete, 0.1. For many... 

Curve 1 (Figure 58) displays distribution of longitudinal elongation by PVS width deformed in an inhomogeneous mechanical field. Countdowns are made for the most deformed part of the film, marked by digits 1-1 in Figure 57, b. It is clear from the Figure that... 

Cmwe 2 (Figure 58) shows dependence of the sample thickness on its width. Coimtdowns are taken by the zero line located in the middle of the sample (Figure 58, b). As would be expected, the sample thickness is reduced as longitudinal elongation increases. 

A variation of the preceding process is used to produce oriented vinyUdene chloride copolymer films. The plastic is extmded into tube form and then is supercooled and subsequently biaxiaHy oriented in a continuous bubble process. The supercooled tube is flattened and passed through two sets of pinch roUs, which are arranged so that the second set of roUs travels faster than the first set. Between the two sets, air is injected into the tube to create a bubble that is entrapped by the pinch roUs. The entrapped air bubble remains stationary while the extmded tube is oriented as it passes around the bubble. Orientation is produced in the transverse and the longitudinal directions, creating excellent tensile strength, elongation, and flexibiUty in the film. The commercial procedure has been described (157). 

Poison s ratio It is the proportion of lateral strain to longitudinal strain under conditions of uniform longitudinal stress within the proportional or elastic limit. When the material s deformation is within the elastic range it results in a lateral to longitudinal strain that will always be constant. In mathematical terms, Poisson s ratio is the diameter of the test specimen before and after elongation divided by the length of the specimen before and after elongation. Poisson s ratio will have more than one value if the material is not isotropic... 

Fig. 4. Spatial distribution of (a) relative elemental elongation rate (longitudinal growth rate) and (p) osmotic potential in the apical 10 mm of maize primary roots growing at various vermiculite water contents (see Fig. 3). Growth distributions were obtained by time-lapse photographic analysis of the growth of marked roots points are means from 5 or 6 roots. Osmotic potentials were measured on bulked samples from 30-50 roots points are means s.d. (n = 3-7). Root elongation rates (a, inset) were constant when the measurements were made. Modified from Sharp et al. (1988, 1989).

Relative to specimens examined under the microscope, the a or fast axis corresponds to the direction of the minimum refractive index, the minimum dielectric constant, and the maximum velocity. The y or slow axis corresponds to the maximum refractive index, the maximum dielectric constant, and the minimum velocity. Occasionally, a (3 axis is recognized with intermediate properties between a and y. When working with elongated bireffingent structures, birefringence usually is taken as positive when the y axis is parallel to the longitudinal axis. 

A dimensionless quantity, symbolized by either s or e, for the change in length (/) due to some force or interaction per unit length thus, s = A///. Linear strain is also known as longitudinal strain. Relative elongation is also measured by A///. 

Quotient of the difference between the longitudinal stress (cth) and the lateral stress (ctzi) and the elongational strain rate ( ) in steady uniaxial flow... 

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