Stress-free spacing

It is, of course, necessary to have an accurate measure of d, the stress-free spacing. The strain results can then be converted into stress using a suitable value of the stiffness (e.g., see Ref. 11). 

An autoclave without a bursting disk and containing the two poorly mixed reactants was wrecked by a violent explosion which occurred on heating the autoclave to 180°C [1]. This was attributed to not allowing sufficient free space for liquid expansion to occur [2], The need to calculate separate reactant volumes under reaction conditions for all autoclave preparations is stressed [3],... 

As noted elsewhere [67], Eq. (14) means that the continuity condition does not prohibit the existence of an electromagnetic current density J in free space. It is stressed that Eq. (14) is a mathematical prediction of Maxwell s equations, completely independent of any interpretation. 

X waves constitute the most striking example of superluminal effects, because they propagate in free space over large distances. We want to stress that the existence of superluminal X-shaped waves was predicted by ER. This is, in our opinion, one of the most impressive among the (verified) ER predictions, and was just put forward as early as 1982 in a fundamental paper by Barut et al. [50]. The point is that, on the basis of ER, an (extended) tachyon is just expected... 

Of course, such large states are rather fragile as stressed above, Rydberg states can only develop if there is enough free space around the atom for the wavefunction of the electron to extend well outside the atomic core. This aspect seems to have been appreciated most clearly in the early days of quantum theory by Sommerfeld and Welker [33], who considered a H atom enclosed in a hollow sphere,10 and showed that, if the radius of the sphere is less than 1.835 ao, then the energy of the system becomes positive, i.e. the electron attempts to escape by exerting a pressure on the inner surface of the sphere. 

It follows from the physical picture outlined previously that the stress relief is in general facilitated by the presence of vacancies, since the effective size of free space in the unit cell increases. Indeed, the results show h higher overall persistence of the band gap of the crystal with vacancy defects with applied pressure. It should be pointed out, however, that the present model of periodically distributed vacancies is restricted in its applicability in real materials the vacancies follow an inhomogeneous, and even random, distribution. 

The determination of the stress state is based on the measurement of the lattice deformation of a polycrystalline materials subjected to stresses. This is accomplished by measuring the change of the /J-values of the interplanar spacing of selected lattice planes hid relative to the stress-free state, D0 ... 

The Schwarzschild solution in nonempty space estimates the stress or energy-momentum tensor T p in terms of an incompressible perfect fluid medium with the same symmetry as before and serves as a simple model of a star. To get the complete picture the interior solution for a sphere of perfect fluid of radius ro is joined continuously with the free-space solution that applies at r > ro > 2m. As before m = nM/( , where M is the mass of the fluid sphere. 

Photooxidation leads to shrinking but the mechanism of the process is different than discussed above. If material has residual stress, some chains are in an extended configuration. If any bond in such a chain is broken by the photooxida-tive process, the chain becomes free to change its position to relax stress and shrinkage follows. Shrinkage up to 30% was measured close to the location in which dehydrochlorination occurred. Because of dehydrochlorination, material in this location lost HCl, which caused formation of free space ready to contract. 

The diameter of as-spun fiber decreased from around 20-30 p,m to about 15 pm after drawing, while the size of the polystyrene morphology reduced about 10%. This indicates the drawing process did not effectively deform the solid dispersed phase, because it is difficult for the draw stress to transfer from the matrix to the dispersed phase through the solid interface, and the free space for the polystyrene phase deformation is limited. 

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