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Energy inverse

We see from Eq. (21) that the internal energy inversion occurs at compression of the system with a positive thermal expansivity and at extension with the negative one. Occurrence of the thermomechanical internal energy inversion in Hookean solids is a result of a different dependence of the work and heat on strain (Fig. 1). [Pg.37]

According to Eq. (20) the compression of isotropic solid polymers having positive thermal expansivity must be accompanied by the internal energy inversion. AU inversion at compression has been estimated71 to occur at strains 5-15%. At compression, irreversible plastic deformations occur which prevents a correct experimental determination of AU. With inversion parameters, AU for isotropic poly-... [Pg.85]

Table 5. Parameters of internal energy inversion on stretching drawn and compressing undrawn polymers7,8)... Table 5. Parameters of internal energy inversion on stretching drawn and compressing undrawn polymers7,8)...
More generally the wave length associated with a material particle is, at constant energy, inversely proportional to Vm (p. 108). [Pg.17]

The heteroatoms in arsole and stibole, like phosphole, are pyramidal, but with reduced planarization energies (inversion barriers) relative to arsines and stibines. The inversion barriers are summarized in Table 12 <1995JMT51>. The steady increase in inversion barriers points to steadily decreasing efficiency of 7t-bonding between carbon and the heteroatom, and probably to greater s character of the lone-pair orbital. [Pg.1163]

Among other rearrangement mechanisms, mention should be made of the so-called trigonal twist and low energy inversion transitions between two structures with close energy values. [Pg.116]

For the DCB Hamiltonian we need to invert all time coordinates to get an operator that conserves the total energy. Inversion of a single time coordinate commutes with the non-relativistic Coulomb operator... [Pg.295]

Ifitschfelder et al. [H9] gives a generalized relation for the variation of the thermal diffusion constant with temperature for gases whose molecules interact with the so-called Lennard-Jones potential function, the difference between a repulsion energy inversely... [Pg.911]

For scattering results at each of a small number of energies, inversion of E — H by the LU decomposition is a method of choice. [Pg.281]

It is of interest to note that the model of rigid spheres with an attractive energy inversely proportional to the sixth power of the distance leads to a more compKcated formula which can also be fitted to the cxperi-... [Pg.27]

Affine deformation Bend Dielectrostriction Direct piezoelectricity Electric polarization Electromechanical materials Electrostriction Flexoelectricity Gibbs free energy Inverse piezoelectrieity Non-affine deformation ... [Pg.489]

Resistance, thermal (symbol, R) - A measure of a material s resistance to the flow of thermal energy, inversely proportional to its thermal conductivity, k. (1/R=k)... [Pg.163]

Nitrogen inversion in a series of bicyclic hydrazines has been characterized from low temperature lineshapes obtained at the natural abundance level (53). Two sets of resonances separated by 1-2 ppm coalesced into singlets in the range 90-100 ppm over the temperature range 250-280 K. Activation free energy inversion barriers of 12.7-14.8 kcal/mol were consistent with those obtained from proton and experiments. Similarly, conformational equilibria in jpis-decahydroquinolines have been elucidated by comparison of shifts in rigid compounds with those in conformationally mobile ones (54). [Pg.233]


See other pages where Energy inverse is mentioned: [Pg.2894]    [Pg.334]    [Pg.44]    [Pg.78]    [Pg.1216]    [Pg.74]    [Pg.270]    [Pg.366]    [Pg.215]    [Pg.220]    [Pg.216]    [Pg.45]    [Pg.912]    [Pg.2894]    [Pg.20]    [Pg.191]    [Pg.310]    [Pg.246]   
See also in sourсe #XX -- [ Pg.17 ]




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Inversion energy

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