Superficial classification

A superficial classification of the most common clay mineral groups can be based upon the number of ions present in the octahedral layer (2 diocatahedral or 3 trioctahedral) and the numbers and the kind of ions... 

Classification of Vitamins. Vitamins are classified as either fat soluble or water soluble. This rather superficial classification is still useful because it indicates the best food source of a vitamin. Table XIX presents the principal vitamins several factors whose significance is still debated (inositol, choline) have not been included. 

Perhaps the simplest classification of flow regimes is on the basis of the superficial Reynolds number of each phase. Such a Reynolds number is expressed on the basis of the tube diameter (or an apparent hydraulic radius for noncircular channels), the gas or liquid superficial mass-velocity, and the gas or liquid viscosity. At least four types of flow are then possible, namely liquid in apparent viscous or turbulent flow combined with gas in apparent viscous or turbulent flow. The critical Reynolds number would seem to be a rather uncertain quantity with this definition. In usage, a value of 2000 has been suggested (L6) and widely adopted for this purpose. Other workers (N4, S5) have found that superficial liquid Reynolds numbers of 8000 are required to give turbulent behavior in horizontal or vertical bubble, plug, slug or froth flow. Therefore, although this classification based on superficial Reynolds number is widely used... 

The above is a typical illustration of many confused notions of the ancients due to the fact that they possessed no knowledge of the elementary constituents of substances. The criteria for classification and nomenclature were based upon superficial phenomena, or upon the sources or the applicability of the substances to particular purposes. So long as the. concept prevailed that all substances consisted of variable quantities of the four Aristotelian elements, and that their properties were determined by the proportion of these elements, it was not possible for them to conceive of the possibility of a method of analysis based upon elementary compositions of bodies as understood in modern times. 

Santos, L., Amaro, T., Costa, C., Pereira, S., Bento, M.J., Lopes, P., Oliveira, J., Criado, B., and Lopes, C. 2003. Ki-67 index enhances the prognostic accuracy of the urothelial superficial bladder carcinoma risk group classification. Int. J. Cancer 105, 267-272. 

Figure 7.7 Classification results for nine turquoise samples. Left digital image right combined VIS/NIR material classification result. Samples a, e and f are true, massive turquoises, sample b is turquoise set in silicate bedrock, h is a true turquoise with different ionic dopants and hence a different colour, sample d is true turquoise powder pressed with a polymeric binder, g is an artificially produced turquoise and c and i are other minerals that look superficially similar to turquoise and are frequently used in counterfeits.

As early as 1947, H. Kalk strongly emphasized the need to systematize liver disease in line with morphological aspects. Initially, his approach was founded on laparoscopic criteria, i. e. size, colour and superficial structures of the liver. Pathohistological examination, however, is indispensable in the classification of most liver diseases. Liver diagnostics is based on four essential pillars, of which histology is still the most important and, in cases of doubt, the decisive factor in determining the diagnosis. (s. pp 75, 76)... 

Classification is always restrictive, as it forces highly variable events into a rigid framework. We will see in this book that so many different factors come into play that it becomes difficult to fit all chemical peels into a simplified and rigid classification of superficial , medium and deep . 

There is a definite association between the size of a primary melanoma lesion and the likelihood of metastases. The prognostic factor originally used to determine survival was based on the cross-sectional profile of the primary tumor. The cross-sectional profile could be evaluated if the deepest invasive tumor cells lay above or below the sweat glands. This assessment was further clarified by Clark, who described the relationship of depth of invasion of the cancer cells to the standard anatomic landmarks of the skin (Table 133-3). Clark s classification is a practical approach for patients with more superficial tumors, because tumors classified as Clark levels I through III seldom metastasize. That classification system has been criticized because of problems associated with practical measurements. Melanoma lesions that occur in the presence of lymphoid infiltration, fibrosis, or even the cells of preexisting nevi are difficult to assess with classic reference landmarks. 

A problem in recognizing trends in these cages is the asymmetry and complexity of the structures. Superficial differences may hide fundamental similarities between cages, and a systematic classification of cages into different families is necessary as a first step to understanding probabilities. We could classify polynuclear structures in at least three ways ... 

Odour has three properties, viz. character, intensity and persistence. All three are subjective and can only be measured in sensory terms. Most correlation work has been done on character since it is, superficially, the easiest to measure. However, the description of an odour is associative, since we have no hard reference points. Difficulties in finding correlations can arise from the use of odour classification systems. For instance, in our fragrance work, we found that the use of the term fruity to describe an odour family led to confusion, since the criteria for a molecule to possess an apple odour are not the same as those for pear. We classify the two together because of the similarity of the botanical sources, but this is not necessarily related to the odour properties. To study structure-odour correlations, we must therefore ensure that we are using meaningful parameters. 

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