Isotropy definition

The term quasi-isotropic iaminate is used to describe laminates that have isotropic extensionai stiffnesses (the same in all directions in the plane of the laminate). As background to the definition, recall that the term isotropy is a material property whereas laminate stiffnesses are a function of both material properties and geometry. Note also that the prefix quasi means in a sense or manner. Thus, a quasi-isotropic laminate must mean a laminate that, in some sense, appears isotropic, but is not actually isotropic in all senses. In this case, a quasi-isotropic... 

The interfacial zone is by definition the region between the crystallite basal surface and the beginning of isotropy. Due to the conformationally diffuse nature of this region, quantitative contents of the interphase are most often determined by indirect measures. For example, they have been computed as a balance from one of the sum of the fractional contents of pure crystalline and amorphous regions. The analysis of the internal modes region of the Raman spectrum of polyethylene, as detailed in the previous section of this chapter, was used to quantify the content of the interphase region (ab). 

Glasses can also be prepared by methods other than cooling from a liquid state, including solution evaporation, reactive sputtering, vapor deposition, neutron bombardment, and shock wave vitrification . These techniques suggest that the purely kinetic explanation of the glassy state is subject to question, and that the previous definitions need to be modified. One proposal would define glasses based on isotropy and relaxation time measurements . 

The traditional definitions of the three principal value components (5i 1, 22, and 533), isotropy 5iso, anisotropy and asymmetry of the chemical shift are equivalent to those of the magnetic shielding. This traditional scheme is indefinite. It leads to a loss of physical and chemical generality which is disadvantageous. Therefore, besides the isotropy two new parameters, span Q and skew k, are often introduced and used instead of the anisotropy A3 and... 

By definition, the second order velocity structure function is the covariance of the difference in velocity between two points in space. A consequence of isotropy is that the structure function can be expressed in terms of a single scalar function. According to the similarity hypotheses of Kolmogorov, the scalar function can be expressed as Bdd x) = Sv Sv is a derived velocity scale sometimes... 

Often the intensity in i , is defined in terms of just one component of velocity so that with isotropy appears instead. Related constant factors that also occur in other definitions such as equation (31) are not introduced herein. 

The existence of an inertial reference system is a sequence of definite characteristics of space and time the uniformity and isotropy of space and uniformity of time. The uniformity of space and time means the equivalence of all positions of free bodies in space at all instants of time, and space isotropy means the equivalence of different directions. Therefore, it is possible to give another definition of an inertial reference system as a system relative to which space is homogeneous and isotropic and time is uniform. 

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