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Additives dissipating,

The energy release rate (G) represents adherence and is attributed to a multiplicative combination of interfacial and bulk effects. The interface contributions to the overall adherence are captured by the adhesion energy (Go), which is assumed to be rate-independent and equal to the thermodynamic work of adhesion (IVa)-Additional dissipation occurring within the elastomer is contained in the bulk viscoelastic loss function 0, which is dependent on the crack growth velocity (v) and on temperature (T). The function 0 is therefore substrate surface independent, but test geometry dependent. [Pg.693]

The dielectric and the conductors are selected to maximize data transmission speed while miiumizing signal loss. In addition, dissipating heat generated by the microcircuits is rapidly becoming an important consideration. If too much heat builds up in the microelectronic device. [Pg.60]

We shall see in the next section that the conditional-diffusion closure may contribute an additional dissipation term. However, since at high Reynolds numbers die velocity and scalar fields should be locally isotropic, this term will be negligible. [Pg.278]

Pressure drops for these higher flow rates are very much larger than would be anticipated from a smooth-liquid-surface model, even if the fluid properties are modified to allow for the appreciable entrained-liquid content. A large additional dissipation of energy must occur because of (1) the behavior of the wavy film as a rough wall, (2) wave generation, and (3) liquid interchange between the film and the gas. [Pg.247]

Anti-Static Additive - dissipates static charge in jet fuel. Static charge buildup can result in unwanted ignition of jet fuel/air mixtures. Use is normally not permitted in aviation gasoline except in Canada and Britain. Use is permitted in civil jet fuel and mandatory in military jet fuel. [Pg.53]

When metals have been but barely calcined, they have. lost only their phlogistou, and are recoverable by the introduction of fresh phlogiston. A more thorough calcination, by long continuance of fire or by additions, dissipates a part of this mercurial principle and as no method has been discovered of supplying it by art, the quantity of metal revivable will be proportionably less. The process is capable of being carried so far that no metal at all shall be recovered, and that the calx shall differ but little from mere earth. ... [Pg.435]

This expression describes the number of vibrons Nq in a nonequilibrium state, Nq = fg (uiq) is the equilibrium number of vibrons. In the linear approximation the polarization operator is independent of Nq and — 2lmIIR(u q) describes additional dissipation. Note that in equilibrium Nq = Nq because lmll<(ujq) = 2 mnR(u)q)fg(wq). See also detailed discussion of vibron emission and absorption rates in Refs. [113-116]. [Pg.308]

On the deformation of the macromolecule, i.e. when the particles constituting the chain are involved in relative motion, an additional dissipation of energy takes place and intramolecular friction forces appear. In the simplest case of a chain with two particles (a dumbbell), the force associated with the internal viscosity depends on the relative velocity of the ends of the dumbbell u1 — u° and is proportional, according to Kuhn and Kuhn (1945) to... [Pg.29]

In all dynamical simulations presented so far, it has been assumed that the electrons stay in their ground state throughout the whole process, i.e. the simulations have been based on the Born-Oppenheimer approximation. Still, at metal surfaces with their continuous spectrum of electronic states at the Fermi energy electron-hole (e-h) pair excitations with arbitrarily small energies are possible. However, the incorporation of electronically nonadiabatic effects in the dynamical simulation of the interaction dynamics of molecules with surface is rather difficult [2, 109, 110]. Hence the role of electron-hole pairs in the adsorption dynamics as an additional dissipation channel is still unclear [4],... [Pg.21]

In all the solutions given in the present chapter, the fluid properties will be assumed to be constant and the flow will be assumed to be two-dimensional. In addition, dissipation effects in the energy equation will be neglected in most of this chapter, these effects being briefly considered in a last section of this chapter. Also, solutions to the full Navier-Stokes and energy equations will be dealt with only relatively briefly, the majority of the solutions considered being based on the use of the boundary layer equations. [Pg.83]

This approach, suggested by D. J. Mead (22) and analyzed by Parfitt et al. 2Z, 23), and later by Plunkett and Lee (21) and by Zeinetdinova et al. (25), results in locally increased strains in the viscoelastic layer in the regions around the cuts, and therefore results in additional dissipation. Parfitt s experimental results... [Pg.330]

Distinction has to be made between the very first moments after the application of the external force and the stationary state, developing soon thereafter. Usually, such stationary states are considered, l.e. inertia is disregarded. This was also done in sec. 3.13. However, when electrokinetic phenomena are studied in alternating fields, various types of inertia start to play prominent roles, leading to additional dissipation. As a consequence, double layer characteristics like the Induced dipole moment, the dielectric... [Pg.477]

The total energy needed to complete fracture of the ligament in case 3 and case 4 are almost equal. The result rules out the hypothesis of significant additional dissipative processes in the laminate as an explanation for the much higher toughness of the laminate. [Pg.363]

In these expressions, Gq and G represent additional dissipative terms to be added to the thermodynamic equation (3.69). Kh represents the vertical eddy diffusion coefficient for heat, which is related to the vertical eddy diffusion coefficient for momentum and tracers (Eq. 3.78) by the Prandtl number Pr ... [Pg.119]

Additional dissipative processes arise from the presence of a secondary component in the polymer matrix or from interactions between the host polymer and the secondary particles. For a given polymer composite, there may exist inclusion cavitation, interfacial cavitation, particle deformation, and crack pinning by constituent particles. [Pg.158]

When the fiUer concentration is increased, various phenomena take place, for example (i) the number of particles per unit volume which come in contact during fire flow increases, (ii) the interparticle attraction and repulsion effects become stronger due to electrostatic cheirges, which depend upon the polarity of the medium, (iii) file rotation of the particles during flow, as well as the formation of doublets and their rotation during flow, produces additional dissipative effects which lead to an increase in the viscosity. [Pg.82]

The second electroviscous effect is due to fire electrostatic repulsion between particles approaching each other and is directly proportional to the square of the particle concentration. The essential feature about this effect is that it occurs at high concentrations of the suspensions (unlike the first electrostatic effects) and when there is an overlap of the double layer. The additional dissipative effects that appear as a result of the repulsion bring about an increase in the viscosity. Chan et al. [164] showed that an expression of the form (4.17) can be used to account for the second electroviscous effect but the coefficient a would then strongly depend on the distance between the centers of the particles and consequently, on the particle concentration. The second electroviscous effect is, at times, known to give rise to non-Newtonian behavior of a suspension as observed by Harmsen et al. [165]. [Pg.106]

The finite, values of [77] imply additional dissipation of energy by mechanisms other than the frictional resistance of beads in the bead-spring model. Theories have... [Pg.217]

A fluid is said to be viscous when there is spatial inhomogeneity in the fluid s velocity field (adapted with permission from Reference 26). Such inhomogeneity can arise both from differential momentum transport of fluid and the presence of particles within the fluid that alter the velocity field, which contribute additional dissipative internal friction to the fluid. The amount of viscosity that a macromolecule contributes to a fluid is easy to measure and can be related to conformational and other properties of the macromolecule, making viscosity measurements a valuable characterization tool. [Pg.91]

The fact that we do not account explicitly for the irrelevant variables at the level of the GENERIC framework leads to entropy increase and additional dissipation at the coarser level of description [11]. [Pg.360]

Energy control systems can either provide the structure with additional dissipation capacity and/or reduce the amotmt of ground input energy transferred to the structure. However, base isolation systems require heavy interventions on the bearing structure (base cut, new foundation structure, etc.) and are therefore rarely suitable for the retrofit of heritage buildings. [Pg.3106]

To incorporate the additional dissipation due to friction, Jenkins and Berzi (2010) used the results of a calculation by Herbst et al. (2000) of the rates of dissipation of the rotational and translational energy in a steady, homogeneous shearing flow. Because numerical simulations indicate that the tractions quickly reach limiting values as the coefficient of sliding friction increases above 0.15, they applied their calculation to spheres in the limit of infinite friction. In this case, the ratio R of the energy of the rotational and translation velocity fluctuations is given by... [Pg.172]

Below Tg, there often exist several more dispersion peaks of the loss modulus spectrum, where some additional dissipation of the applied mechanical energy takes place. The positions of these peaks are called sub-Tg or secondary transition regions. They are called the P-transition temperature, y-transition temperature, and so on, in the descending order, as the a-transition of an amorphous material is the glass-to-rubber transition. The storage modulus spectrum is usually quite insensitive to the secondary transitions virtually no changes are observed at transition temperatures corresponding to the peaks of a loss modulus spectrum. [Pg.777]


See other pages where Additives dissipating, is mentioned: [Pg.46]    [Pg.202]    [Pg.490]    [Pg.351]    [Pg.363]    [Pg.100]    [Pg.9]    [Pg.12]    [Pg.241]    [Pg.318]    [Pg.767]    [Pg.202]    [Pg.251]    [Pg.328]    [Pg.158]    [Pg.137]    [Pg.218]    [Pg.162]    [Pg.293]    [Pg.104]    [Pg.931]    [Pg.303]    [Pg.373]    [Pg.349]    [Pg.656]   
See also in sourсe #XX -- [ Pg.36 ]




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