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Exponents elasticity

As is evident, there are several distinctive characteristics of adhesion-induced plastic deformations, compared to elastic ones. Perhaps the most obvious distinction is the power-law dependence of the contact radius on particle radius. Specifically, the MP model predicts an exponent of 1/2, compared to the 2/3 predicted by either the JKR or DMT models. [Pg.159]

In order now to evaluate the exponent rp we make recourse to the law of mixtures, given by relation (21), which expresses the elastic modulus of the composite in terms of the moduli and the radii (or volume fractions) of the constituent phases. This relation yields the average elastic modulus for the mesophase Ef. Then, it is valid for the mesophase layer that ... [Pg.170]

Overall bed-to-surface heat transfer coefficient = Gas convective heat transfer coefficient = Particle convective heat transfer coefficient = Radiant heat transfer coefficient = Jet penetration length = Width of cyclone inlet = Number of spirals in cyclone = Elasticity modulus for a fluidized bed = Elasticity modulus at minimum bubbling = Richardson-Zaki exponent... [Pg.148]

Thus, the model predicts that thermal fluctuations in the tilt and curvature change the way that the tubule radius scales with chiral elastic constant— instead of r oc (THp) 1, the scaling has an anomalous, temperature-dependent exponent. This anomalous exponent might be detectable in the scaling of tubule radius as a function of enantiomeric excess in a mixture of enantiomers or as a function of chiral fraction in a chiral-achiral mixture. [Pg.354]

Despite the obvious correspondence between scaled elasticities and saturation parameters, significant differences arise in the interpretation of these quantities. Within MCA, the elasticities are derived from specific rate functions and measure the local sensitivity with respect to substrate concentrations [96], Within the approach considered here, the saturation parameters, hence the scaled elasticities, are bona fide parameters of the system without recourse to any specific functional form of the rate equations. Likewise, SKM makes no distinction between scaled elasticities and the kinetic exponents within the power-law formalism. In fact, the power-law formalism can be regarded as the simplest possible way to specify a set of explicit nonlinear functions that is consistent with a given Jacobian. Nonetheless, SKM seeks to provide an evaluation of parametric representation directly, without going the loop way via auxiliary ad hoc functions. [Pg.195]

The data show that the ratio of elastic to total pressure is higher, the higher the loading density. Thus, near the C-J state, the LSZK isentrope may be approximated by a polytropic relation with exponent 2.78, in agreement with Deal s experimental value of r= 2.77, at least down to 500 bar. The LSZK equation thus seems to yield not only the proper D— p0 relationship but also the proper isentrope, both near the C-J state and in the large low-pressure low-density expansion limit... [Pg.553]

In addition to the increase in tensile strength and elasticity of propellants, these bonding agents [221] also reduce the burn-rate exponent (n). [Pg.277]

Ham and co-workers (173) compared a LDPE with three HDPE samples, the MJMn ratios of which bracketted that of the LDPE their non-Newtonian behaviour, as measured by the exponent in a power-law relationship between stress and shear rate, also bracketted that of the LDPE. However, the LDPE had considerably higher melt elasticity than the HDPE, which was ascribed to LCB. [Pg.52]

Crosslink density directly affects E0 (through rubber elasticity), and has an indirect influence on E (through the antiplasticization effect). Cole-Cole plots open the way to analyzing the distribution of relaxation times (the exponents a and y or % or % are linked to the width of the distribution of relaxation times). According to the results of Table 11.3, these exponents seem to depend more on the molecular-scale structure (they vary almost... [Pg.355]

The elastic-plastic model reveals that the restitution coefficient depends not only on the material properties but also on the relative impact velocity. Equation (2.166) also indicates that the restitution coefficient decreases with increasing impact velocity by an exponent of 1/4, which is supported by experimental findings, as shown in Fig. 2.18. For high relative impact velocities, the model prediction is reasonably good. However, for low relative impact velocities, the prediction may be poor because the deformation may not be in a fully plastic range as presumed. [Pg.81]

The second equation appears to be applicable to a number of glassy polymers, and also to other materials the exponent m is always about 3, so that creep can be described by two parameters, Do and to, while the immediate elastic deformation is also taken into account (Do). As a matter of fact, Do and to are temperature dependent. When the experimentally found creep curves are shifted along the horizontal axis and (slightly) along the vertical axis, they can be made to coincide... [Pg.120]

Keywords Monolayers Surface light scattering Capillary waves Dispersion equation Dilational elastic modulus Dilational loss modulus Scaling exponent... [Pg.60]

Neutron elastic scattering is one of the most powerful tools in the determination of the magnetic structure of an ordered material. At the onset of magnetic order additional reflections on the nuclear pattern are created, due to interactions between the electrons of the nuclei. The variation of the intensity of these magnetic reflections with temperature yields the ordering temperature as well as the spontaneous magnetization of the sublattices and thus the critical exponent /5. [Pg.99]

Accordingly, we expect a power law behavior G,0 (O/Op)3 5 of the small strain elastic modulus for 0>0. Thereby, the exponent (3+df [j)/(3—df)w3.5 reflects the characteristic structure of the fractal heterogeneity of the filler network, i.e., the CCA-clusters. The strong dependency of G 0 on the solid fraction Op of primary aggregates reflects the effect of structure on the storage modulus. [Pg.57]

An important role in the present model is played by the strongly non-linear elastic response of the rubber matrix that transmits the stress between the filler clusters. We refer here to an extended tube model of rubber elasticity, which is based on the following fundamental assumptions. The network chains in a highly entangled polymer network are heavily restricted in their fluctuations due to packing effects. This restriction is described by virtual tubes around the network chains that hinder the fluctuation. When the network elongates, these tubes deform non-affinely with a deformation exponent v=l/2. The tube radius in spatial direction p of the main axis system depends on the deformation ratio as follows ... [Pg.65]

Here, pc 0.2 is the critical occupation number where a percolation network is formed and r = 3.6 is the elasticity exponent of percolation [91 ]. For large values of p (p >p<), Eq. (75) can be approximated by a function of the Havriliak-Negami type ... [Pg.38]

The established concepts predict some features of the Payne effect, that are independent of the specific types of filler. These features are in good agreement with experimental studies. For example, the Kraus-exponent m of the G drop with increasing deformation is entirely determined by the structure of the cluster network [58, 59]. Another example is the scaling relation at Eq. (70) predicting a specific power law behavior of the elastic modulus as a function of the filler volume fraction. The exponent reflects the characteristic structure of the fractal heterogeneity of the CCA-cluster network. [Pg.40]


See other pages where Exponents elasticity is mentioned: [Pg.1118]    [Pg.1118]    [Pg.472]    [Pg.886]    [Pg.117]    [Pg.272]    [Pg.493]    [Pg.82]    [Pg.273]    [Pg.275]    [Pg.132]    [Pg.132]    [Pg.220]    [Pg.110]    [Pg.294]    [Pg.231]    [Pg.302]    [Pg.126]    [Pg.123]    [Pg.90]    [Pg.174]    [Pg.231]    [Pg.20]    [Pg.112]    [Pg.149]    [Pg.472]    [Pg.292]    [Pg.336]    [Pg.255]    [Pg.111]    [Pg.12]    [Pg.131]   
See also in sourсe #XX -- [ Pg.2 , Pg.16 , Pg.17 ]




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