Silicate terminology

Table 4.2 summarizes this basic classification and terminology of silicates. It is worth remembering that the term infinite refers here to an atomic scale of measurement, and does not imply that the chains extend to infinity in the mathematical sense of the word The terminology surrounding the silicates and clay minerals, in common with other mineralogical terms, has never been fully systematized, and so the names given are often ill-defined, or not unique to a... 

The concept of a fractal dimension enables the structures of silicate species to be divided into two classes (1) those with a dimension less than 3, which may be considered to be true polymers, and (2) those with a dimension of 3, which are perhaps best described as colloidal particles (5). The colloidal class may be further subdivided into particles with fractally rough surfaces (D > 2) and particles with smooth surfaces (D = 2). In this chapter, the term polymer will be used for any product of the condensation reaction, regardless of fractal dimension, although the term polymeric will be used for structures with dimensions less than 3, and the term colloidal will be used for structures with dimensions equal to 3, in keeping with the terminology used in the literature (9). 

In eastern Kentucky the Ohio Shale terminology has been used where the Mississippian Sunbury Shale and the underlying Bedford Shale can still be recognized. A typical stratigraphic section with carbon distribution is shown in Figure 3. Typically the overburden is a mixture of claystone and siltstone in the Borden Formation. This unit directly overlies the Sunbury Shale which is a black, laminated, siliceous shale rich in organic matter with some pyrite. The Sunbury thins to the south from 20-25 feet in Lewis County to four feet in Estill County. 

It is difficult to define precisely the term aqueous silica sols and thereby contrast them with other forms of silica (colloidal silica, colloidal quartz, pyrogenic silica, and so forth). Bulk chemical distinctions are not very useful. The definition chosen here follows Iler s terminology (I). Aqueous silica sols are characteristically composed of spherical particles nucleated and grown by alkaline hydrolysis of sodium silicate solutions. They are often monodisperse systems and have particle diameters in the range 1-100 nm (density, —2.2 g/cm3) that lead to sols that vary from optically transparent to opalescent. 

Following Chemical Abstract Service terminology, the commercial soluble silicates were reported to the initial inventory of existing chemical substances as indicated in Table... 

From these and numerous other examples it follows that Graham s classification relates to mixtures rather than to chemically pure substances. A discussion of colloids from this point of view would have to do not with pure substances and their properties, but rather with those mixtures of substances which have colloidal properties. Ordinary chemical terminology also justifies this standpoint in that by colloidal silicic acid, gold, or platinum, for example, we understand not... 

When the cement comes into contact with water, chemical reactions start between the clinker minerals (CaO = C, Si02=S, AI2O3 = A) and the water (abbreviated in the terminology as H ), forming colloidal, insoluble reaction products such as calcium silicate hydrates (CSH), calcium aluminate hydrates (CAH) ... 

The composition and use of calcium copper silicate as a pigment has been extensively discussed by Riederer (1997a) and Scott (2002). Terminology surrounding this compound is discussed under Egyptian blue. 

Nomenclature used in the organo-silicate literature, alcohol condensation and water condensation, is equivalent to the terminology, alcoxolation and oxolation, used in the discussion of inorganic polymerization in the previous chapter. 

Unlike silicate ceramics, raw materials used for the preparation of non-silicate ceramics are generally synthetic powders and not mixtures of crashed rocks. But these synthetic powders can result from natural products, which the English terminology makes easy to understand by distinguishing between starting materials (for example, alumina powders) and raw materials (bauxite rocks, in this case, whose treatment by the Bayer process yields the alumina powders) [CAS 90],... 

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