Mineralizers/fluxing agents

These examples, and most of the published literature, suggest the potential hazards in making large-scale generalizations about raw feed burnability, presumably because of the combined effects of variable mineral- and particle-size distributions, the relative proportions of "fluxing" agents, and kiln conditions. 

However, in 1886, American engineer Charles Martin Hall and French engineer Paul Heroult simultaneously but independently announced that they had discovered how to electrowin aluminum metal from alumina. Because aluminum oxide melts at such a high temperature (i.e., 2030 C) and is a nonionic (i.e., nonconductive) Hquid, electrolysis of the molten oxide is not feasible. What both Hall and Heroult discovered was that a natural fluoride mineral called cryolite (i.e., Na AlF, monoclinic), which occurs naturally in Greenland and melts at only 1009 C, would act as fluxing agent and easily dissolve purified aluminum oxide. This molten salt mixture could then be electrolyzed using carbon electrodes. 

Ceramizable silicone-based materials are dispersion t5q)e of composites, in which mineral particles (refractory fillers and, in some compositions, fluxing agent particles) are dispersed in continuous phase of silicone rubber [1-18]. Mechanism of protecting ceramic shield creation on the border between fire and material includes ... 

Figure 2.46. The milk-white mineral cryolite NagAlFg is used as a fluxing agent in the electrolytic production of aluminium. The cryolite itself is not involved in the reaction the raw material is the Al-containing bauxite A120 . Cryolite is a rare mineral. A well-known occurrence is found at Ivigtut in Greenland.

The tendency to form boiler waterside deposits is partly dependent on factors such as the solubility of the particular mineral species and the strength of physical adherence involved. As a general rule, the rate of deposition tends to increase with higher levels of BW dissolved solids. Also, the rate of deposition increases with increase in heat-flux density and with the inadequate dosage, inappropriate feeding, or otherwise usage of antisealants and other deposit control agents (DCAs). 

The mechanism of action of the vitamin D metabolites remains under active investigation. However, calcitriol is well established as the most potent agent with respect to stimulation of intestinal calcium and phosphate transport and bone resorption. Calcitriol appears to act on the intestine both by induction of new protein synthesis (eg, calcium-binding protein and TRPV6, an intestinal calcium channel) and by modulation of calcium flux across the brush border and basolateral membranes by a means that does not require new protein synthesis. The molecular action of calcitriol on bone has received less attention. However, like PTH, calcitriol can induce RANK ligand in osteoblasts and proteins such as osteocalcin, which may regulate the mineralization process. The metabolites 25(OH)D and 24,25(OH)2D are far less... 

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