Stress-strain relationship INDEX

Figure 7.4 Stress-strain relationships for dough of good and poor bread-making flours (left) and the relationship between strain hardening index and baked loaf volume (right). (Data from Dobraszczyk, B. J. 1999. In Bubbles in food, ed. G. M. Campbell, C. Webb, and S. S. Pandiella, 173-182. St. Paul, MN AACC International.)...

According to the stress-strain relationship proposed by Statistical Mechanics of Rock-Mass (Wu F Q et al. 2001), an index for EDZ zoning has been derived as ... 

In the case of lateral compression, the propagated fundamental mode perfectly degenerates into x- and y-polarized modes with different propagation constants. According to the photoelastic effect and the stress strain relationship, the effective index changes of the two polarized modes ean be expressed as ... 

Another characteristic of the silica fibre is the non-linear stress-strain relationship. It is known that the neutral axis is also shifted toward the outer side of the fibre under bending. Its direct effect on the FBG is that the grating period will be compressed, so these effects should also be considered, together with the change of effective refractive index of the FBG under bending. 

The data in Figure 2.9 demonstrate the marked influence of density on the creep behavior of polyethylene. The curves in Figure 2.9 are relevant to a total strain of 1%, but similar plots for other permissible strains can be readily derived from the isochronous stress-strain curves. The linear relationship between creep and density for polyethylene at room temperature, irrespective of the melt index over the range investigated (i.e., 0.2-5.5), has enabled the stress-time curve of Figure 2.10 to be interpolated for the complete range of polyethylene. In this case, the data have been based on a permissible strain of 2%, but as previously explained, data for other permissible strains can be similarly interpolated from the creep curves. 

Fig. 11.4 (a, b) Stress-strain curves of unoriented compression moulded films of the samples in Table 11.1 (De Rosa et al. 2004, 2005) (c, d) Average values of Young Modulus as a function of crystallinity index (c) and relationship between the lamellar thickness 4 and the yield stress Oy (d) of iPP samples with the indicated concentrations of rr stereo-defects ((a, b) Reprinted from De Rosa et al. 2005 with permissions)... 

The parameter determined by integration of the stress/strain history is the critical thermomechanical conversion factor, fic- As noted both in experiments [5] and in simulations [6], drawing is destabilised at a temperature of 50-60°C, i.e. within the range for which data were measured. Figure 4 shows that despite experimental and analytical uncertainties provides a very effective index for the plane stress fracture resistance Wpi they are related by a monotonic and, indeed, quite linear relationship. Figures 5 and 6 illustrate the robusmess of the procedure in that neither the initial temperature of the simulation nor the strain rate chosen to characterise plane stress separation unduly influences the result. 

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