Gross uniformity,

Since texture has a great deal to do with visual perception, it is interesting to discuss some work done on texture recognition. The first question we want to focus on is what makes two samples with identical overall concentration exhibit different textures Perfect gross uniformity implies identical concentration in all samples. Julesz (68), in an interesting... 

In conclusion, mixtures are characterized by gross uniformity, texture, and local structure. Having discussed composition uniformity qualitatively, we now proceed to deal with the quantitative aspects of characterization of mixtures. 

Skelland and Lee showed that gross uniformity of dispersion was obtained with values of N that exceeded by an average of about 8%. Purthermore, it was found by Skelland and Moed that Eq. 

Physiological hyperplasia in response to iodine deficiency Gross Uniform enlargement of the gland on section, surface is amber color, translucent, and honeycombed ... 

It expresses the ratio of the measured variance to the variance of a completely segregated system. The intensity of segregation as defined in equation (5.10) reflects to some extent gross uniformity on a scale of examination reduced to the scale at which texture or local structure is being examined. 

Gross uniformity is important in most mixtures. However, the degree of fineness in the texture that is needed is, of course, dependent upon the individual application requirements of the mixed material. In order to evaluate the texture, the size of file analyzed samples has to be reduced to the level which permits characterization of the texture significant to a specific appfication. On the other hand, the local structure has to 1 examined at the scale of the ultimate particles. Naturally, the local structure would depend upon the efficiency of fite mixing action and also upon file compatibility of the materials. 

Usually it is sufficient to characterize any mixture by its gross uniformity, texture, and local structure. The term gross uniformity can also be found in the literature as overall uniformity or gross composition uniformity. In the example of carbon black mixed into PE, the gross uniformity indicates the goodness of the concentration distribution of carbon black, and it can be evaluated by statistical analysis on a number... 

The presence of texture in the samples is important in polymer processing, as (1) laminar mixing produces texture (2) the mechanical properties of polymer blends depend on the texture (e.g., skin-core formation, fiber orientation, and distribution of voids along the thickness in structural foams) and (3) the lack or the presence of texture is required in certain products. Samples can exhibit a certain texture, and at the same time they do or do not exhibit concentration gross uniformity. 

The scale of examination for textures might differ from that for gross uniformity. However, the upper and lower limits, in both cases, remain the same. When the scale of examination is about the same as the scale of the ultimate... 

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