Eyring theorem

As reported by Ward and Hadley (1993), the theoretical basis of Eq. 23.79 can be found in the Eyring theorem, according to which the mechanical response of an adhesive is a process that has to overcome a potential barrier, (A ). This barrier decreases not only with increasing stress but also with increasing temperature. Based on the Eyring theorem, the relationship between a limit stress, say Tei, and the strain rate can be written as ... 

We have found (x for any harmonic-osdllator stationary state without evaluating any integrals. This result was also obtained from the virial theorem see Eq. (14.16). For a third derivation, see Eyring, Walter, and Kimball, p. 79. 

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