Glass, inorganic definition

Insulation systems were first classified according to the material used, and permissible temperatures were established based on the thermal aging characteristics of these materials. For example. Class B insulation was defined as inorganic materials such as mica and glass with organic binders 130°C was the allowable maximum operating temperature. The present definition of insulation system Class B stipulates that the system be proven. . by experience or accepted tests. .. to have adequate life expectancy at its rated temperature, such life expectancy to equal or... 

Glass is a rigid, undercooled liquid having no definite melting point and a sufficiently high viscosity to prevent crystallization that results from the union of the nonvolatile inorganic oxides, sand, and other constituents, and thus is a product with random atomic structure. 

Also, fibers are controversial. In one currently used handbook, natural, inorganic fibers such as wollastonite or asbestos have been included among fillers whereas other fibers were included in a separate group with only three materials glass, aramid, and graphite. But, mixtures of fibrous and particulate materials are found in many composites today and various natural materials having fibrous structures are considered fillers in technical papers. Again our definition includes these examples. 

The ability to withstand thermal shock resulting from sudden changes in temperature is important for technical applications of glass. The thermal endurance of inorganic glass, studied mainly by Schott and Winkelmann [24] (see also refs. [1] and [25]), is a very complex property. The investigations have led to the definition of a coefficient of thermal endurance F ... 

After that a multicomponent oxide glass can no longer be regarded as an inorganic product of fusion (ASTM definition) [9]. 

Pioneering work of Tool [1946, 1948] on inorganic glasses using dilatometry indicated that volume relaxation after a temperature jump from an initial equilibrium state could not be described simply by a kinetic model in which the relaxation time T was solely dependent on the temperature. Tool therefore proposed that r was also a function of the structure of the glass, and this led to the definition of the Active temperature Tf. 

Most of the solid components of the Earth s crust, i.e. rocks, sediments, clays etc. are largely made up of various mineral species. Amineral species is deiined as A naturally occurring, inorganic, homogeneous solid, having a definite (but not necessarily fixed) chemical composition and a fixed ordered internal structure, i.e. crystalline. This ordered internal structure is reflected in the external morphology when the mineral has a well crystalline form. When the crystalline form is not perceptible externally called cryptocrystalline, its crystalline nature can be detected by scientific analytical techniques like X-Ray Difiraction. Amorphous natural solids like coal, volcanic glasses etc. do not qualify as minerals. The abimdance of any mineral in the Earth is decided by the availability of the constituent elements of the mineral in the earth s crust and also the stability of that mineral in the surface or near-surface environment. 

It is important to be precise with regard to the definition of the industrial chemical industry as it is compared with the electrochemical industry. The products of the industrial chemical industry occupy the two government SIC codes, 281, inorganic and organic chemicals, and 282, plastics materials, synthetic resins, synthetic rubber, synthetic, and other man-made fibers except glass. A list of the major product categories in SIC 281 and 282 is contained in Table 3A. 

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