Overshoot peak

In an attempt to better understand the role of receptor internalization, a minimal model has been developed using hypothesis testing [10]. The model is based on experimental data on autophosphorylation of the IR. Upon addition of insulin to intact adipocytes, the IR rapidly autophosphorylates with an overshoot peak before t = 0.9 min, and then slowly declines to a quasi-steady state at around 15 min. 

Figure 3 demonstrates the simulated tissue overshoot with a pure delay of 20 sec and time constant lag of 10 sec. Manipulation of the two variables yields overshoot peaks of various amplitudes and shapes. 

FIGURE 6.20 Maximum in transient viscosity after initiation of shear flow varsus the duration of a quiescent interval between shearing. The growth of the overshoot peak is caused by reentanglement of the solution. The inset shows representative transient shear stress data (Roland and Robertson, 2006). 

In Figure 4 we have plotted values of the primary normal stress difference (N ) versus time. Here we observe that a single overshoot peak is observed in N. The peak stress occurs at strains of the order of 40 to 6o strain units which is similar to the range observed for the appearance of the second peak in the shear stress. Whereas the shear stress rises rapidly at the start up of flow, the normal stresses rise gradually. It should be pointed out that this is exactly the behavior predicted by the corotational Jeffrey s model. ... 

The 80 mole % PHB/PET system exhibits similar behavior for the shear stress as the 60 mole % PHB/PET system. This is illustrated in Figure 7 where two overshoot peaks are observed on the start up of flow. On reversing the flow direction, the stress almost rises instantaneously to its equilibrium value. On stopping the flow, the shear stress relaxes rapidly to zero stress. 

Once the specimen turns to a superconducting state, the obtained superconductor-insulator-normal metal (SIN) spectrum probes the quasiparticle excitation in the superconductor, which directly reflects the symmetry of the order parameter A(k). If A(k) has simple s-wave symmetry, as is realized in conventional low-temperature superconductors, one expects a finite gap of A with overshooting peaks just outside the gap in N(E), as illustrated in fig. 6. Even if A(k) possesses anisotropic s-wave symmetry, a finite gap, corresponding to the minimum gap, appears. In dx2-yi superconductors with A(k) = coslkx - cos 2, in contrast, N(E) is gapless with linear N(E) for E A. It is noted that the extended-s wave A(x) = cos 2kx + cos 2ky is also characterized to possess a gapless feature with two singularities bX E = A and A2. 

Figure 9.14(a) schematically shows the relation between strain hardening, stress overshoot, and the steady nonlinear viscosity in a shear-thinning regime. For a sufficiently high shear rate, the viscosity first shows an upward deviation due to strain hardening, followed by an overshoot peak, and then asymptotically decreases to the stationary value. The stationary viscosity is plotted in Figure 9.14(b). 

Figure 8.3 DSC curves for samples with different thermal histories. Well-armealed samples display a substantial overshoot peak. Curve 4 was for a quenched and immediately reheated sample. Curves 1 to 3 were for increasing annealing up to 7 days for curve 3. (From Kovacs, A.J., Glass transition in amorphous polymers a phenomenological study, Adv. Polym. Sci, 3, 394, 1963. With permission.)...

Steady shear, but also shifts the stress overshoot peak assigned to the matrix phase to a lower shear deformation than that observed in unfilled melt. This behavior has been quantitatively addressed in the present study. 

Figure 12.35 shows variations of shear stress growth a+(y, /)) as a function of shear strain (yt) upon startup of shear flow at 260°C and y = 1.0 s for 95.7/4.3 PC/MMT nanocomposite and 95.7/4.3 PC/Cloisite SOB nanocomposite, where three separate runs, each using a fresh specimen, were made. Thus, the three curves given in Figure 12.35 represent variability of a+(y,t) on three repeated measurements. The following observations are worth noting in Figure 12.35. Upon startup of shear flow, both 95.7/4.3 PC/MMT and 95.7/4.3 PC/Cloisite SOB nanocomposites exhibit an overshoot followed by monotonic decay reaching steady state, and the magnitude of overshoot peak 95.7/4.3 PC/Cloisite SOB nanocomposite is...

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