![]() The composition was studied of calcium aluminosilicate microspheres of three morphological types in high- calcium fly ash from combustion of brown coal from the Kansk-Achinsk basin in slag-tap boilers at temperatures from 1400 to 1500Â☌ and sampled in the first field of electrostatic precipitators at the Krasnoyarsk Cogeneration Power Station no. 2008).Ĭomposition and structure of calcium aluminosilicate microspheres 2004) suggests that the viscosity maximum does not correspond exactly with the disappearance of NBO from the glasses, but effects of temperature on speciation will need to be taken into account to accurately link glass structure with melt properties: recent work has shown, for example, that NBO content increases with temperature in CaAl2Si2O8 melt (Stebbins et al. Comparison with published viscosity measurements measured at both higher and lower mol % SiO2 (Toplis et al. 27Al MAS NMR spectra of these glasses show an increase in the amount of five-coordinated aluminum as compositions become more peraluminous, as is well-known from previous studies (Neuville et al. Measurable amounts of NBO thus persist well into the peraluminous region of the CAS system, but the species becomes undetectable (<0.5%) when R reaches 0.38 and 0.33. 17O MAS NMR spectra of glasses with 60 mol% SiO2 show a decrease in NBO as the ratio R=Ca+2/(Ca+2Al) decreases, from 6.9% at R=0.56 to 1.0% at R=0.44. Using NMR spectroscopy, this study investigates the effects of the Ca/Al ratio on the amount of NBO present in calcium aluminosilicate (CAS) glasses. Much of the recent work has concentrated on glasses with an M+n/(M+nAl) ratio greater than or equal to 0.5 (metaluminous to peralkaline or per-alkaline earth) however, the observed viscosity maxima in several ternary systems occur when this ratio is less than 0.5 (peraluminous). Its existence along metaluminous joins in alkali- and alkaline-earth aluminosilicates was first postulated from viscosity measurements (Toplis et al., 1996, 2004) and then directly observed in several metaluminous calcium aluminosilicates by 17O nuclear magnetic resonance (NMR) spectroscopy. The role of non-bridging oxygen (NBO) and its effects on the thermodynamic and transport properties of aluminosilicate melts are not fully understood, although this species clearly must have a major influence on configurational entropy, viscosity, etc. Non-bridging Oxygens in Calcium Aluminosilicate Glass From Per-calcic to Peraluminous Compositions This substance is generally recognized as safe. Hydrated sodium calcium aluminosilicate (sodium calcium silicoaluminate). Agents § 582.2729 Hydrated sodium calcium aluminosilicate. 21 Food and Drugs 6 false Hydrated sodium calcium aluminosilicate. Hydrated sodium calcium aluminosilicate (sodium calcium silicoaluminate.Ģ1 CFR 582.2729 - Hydrated sodium calcium aluminosilicate. (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Anticaking Agents § 182.2729 Sodium calcium aluminosilicate, hydrated. 21 Food and Drugs 3 false Sodium calcium aluminosilicate, hydrated. ![]() ![]() § 182.2729 Sodium calcium aluminosilicate, hydrated. 21 Food and Drugs 3 true Sodium calcium aluminosilicate, hydrated. 21 CFR 182.2729 - Sodium calcium aluminosilicate, hydrated.
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