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Contribution elastic

Gluten is a mixture of proteins that can be classified as glutenins and gliadins. Extensibility is provided by glutenins while the gliadins contribute elasticity and cohesiveness. [Pg.33]

The structure of this interface determines fhe sfabilify of PEMs, the state of water, the strength of interactions in the polymer/water/ion system, the vibration modes of side chains, and the mobilities of wafer molecules and protons. The charged polymer side chains contribute elastic ("entropic") and electrostatic terms to the free energy. This complicated inferfacial region thereby largely contributes to differences in performance of membranes wifh different chemical architectures. Indeed, the picture of a "polyelectro-lyfe brush" could be more insighttul than the picture of a well-separated hydrophobic or hydrophilic domain structure in order to rationalize such differences. ... [Pg.356]

The confinement of water in nanometer-size pores between the walls of the polymer material affects the structure of water. The observed freezing-point suppression [49,50] and reduced dielectric constant of water [115-117], are macroscopic manifestations of this effect. The interfacial area between polymer and water provides a complex environment for proton transport. The complications for the theoretical description are caused by the flexibiHty of the sidechains, their random distributions and their partial penetration into the bulk of water-filled pores. The charged polymer sidechains contribute elastic ( entropic ) and electrostatic terms to the free energy [54,55]. Distribution and mobilities of protons depend strongly on the resulting sidechain-water interactions [54,56,118]. [Pg.31]

Consider the same bend distortions caused by field and shown in Fig. 11.28 and assume that distortions are small. What happens if we switched the field off In the torque balance equation for Frederiks distortion (a), we shall have two contributions, elastic and viscous ... [Pg.331]

Elasticizer n. A compounding additive that contributes elasticity to a resin such as chlorinated polyethylenes and chlorinated... [Pg.343]

The interest in vesicles as models for cell biomembranes has led to much work on the interactions within and between lipid layers. The primary contributions to vesicle stability and curvature include those familiar to us already, the electrostatic interactions between charged head groups (Chapter V) and the van der Waals interaction between layers (Chapter VI). An additional force due to thermal fluctuations in membranes produces a steric repulsion between membranes known as the Helfrich or undulation interaction. This force has been quantified by Sackmann and co-workers using reflection interference contrast microscopy to monitor vesicles weakly adhering to a solid substrate [78]. Membrane fluctuation forces may influence the interactions between proteins embedded in them [79]. Finally, in balance with these forces, bending elasticity helps determine shape transitions [80], interactions between inclusions [81], aggregation of membrane junctions [82], and unbinding of pinched membranes [83]. Specific interactions between membrane embedded receptors add an additional complication to biomembrane behavior. These have been stud-... [Pg.549]

Phonons are nomial modes of vibration of a low-temperatnre solid, where the atomic motions around the equilibrium lattice can be approximated by hannonic vibrations. The coupled atomic vibrations can be diagonalized into uncoupled nonnal modes (phonons) if a hannonic approximation is made. In the simplest analysis of the contribution of phonons to the average internal energy and heat capacity one makes two assumptions (i) the frequency of an elastic wave is independent of the strain amplitude and (ii) the velocities of all elastic waves are equal and independent of the frequency, direction of propagation and the direction of polarization. These two assumptions are used below for all the modes and leads to the famous Debye model. [Pg.412]

The Debye model is more appropriate for the acoustic branches of tire elastic modes of a hanuonic solid. For molecular solids one has in addition optical branches in the elastic wave dispersion, and the Einstein model is more appropriate to describe the contribution to U and Cj from the optical branch. The above discussion for phonons is suitable for non-metallic solids. In metals, one has, in addition, the contribution from the electronic motion to Uand Cy. This is discussed later, in section (A2.2.5.6T... [Pg.414]

Atomistically detailed models account for all atoms. The force field contains additive contributions specified in tenns of bond lengtlis, bond angles, torsional angles and possible crosstenns. It also includes non-bonded contributions as tire sum of van der Waals interactions, often described by Lennard-Jones potentials, and Coulomb interactions. Atomistic simulations are successfully used to predict tire transport properties of small molecules in glassy polymers, to calculate elastic moduli and to study plastic defonnation and local motion in quasi-static simulations [fy7, ( ]. The atomistic models are also useful to interiDret scattering data [fyl] and NMR measurements [70] in tenns of local order. [Pg.2538]

The element of work is generally written -p dV, where p is the external pressure, but with the possibility of an elastic contribution, it is -p dV + F dL. With this substitution Eq. (3.5) becomes... [Pg.139]

A good compilation of the functions of fats in various food products is available (26). Some functions are quite subtle, eg, fats lend sheen, color, color development, and crystallinity. One of the principal roles is that of texture modification which includes viscosity, tenderness (shortening), control of ice crystals, elasticity, and flakiness, as in puff pastry. Fats also contribute to moisture retention, flavor in cultured dairy products, and heat transfer in deep fried foods. For the new technology of microwave cooking, fats assist in the distribution of the heating patterns of microwave cooking. [Pg.117]

It is possible to show from the inequality (5.55) that the inelastic contribution to the stress rate is directed along the inward normal to the elastic limit surface in strain space, i.e.,... [Pg.138]

The inelastic contribution to the strain rate is directed along the outward normal to the elastic limit surface in stress space. [Pg.139]

The total strain rate in the material is assumed to be the sum of elastic and plastic contributions... [Pg.222]


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See also in sourсe #XX -- [ Pg.42 , Pg.105 , Pg.153 , Pg.154 ]




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Elastic constants electrostatic contribution

Enthalpic and Entropic Contributions to Rubber Elasticity Force-Temperature Relations

Enthalpic and Entropic Contributions to Rubber Elasticity The Force-Temperature Relations

Rubber elasticity energy contribution

The Internal Energy Contribution to Rubber Elasticity

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