DiSilicate, sodium

Silica deposition in the temperature range of 500 to 700 °F (260-371 °C) is primarily sodium disilicate [Na6(Si207)2 alternatively given the formula fJ-Na Oj]... 

Utilizing this description of silicate glass formation, we suggest models to explain the incorporation of 4+ and 6+ actinide ions in sodium disilicate glass. During cooldown,... 

In contrast, disilicate glasses containing U 4+ showed much less leach resistance. The 4+ glass was only slightly more leach resistant than pure sodium disilicate glass which is water soluble. For 4+ glasses, the ph of the leach solution... 

Marlon ARL B.O Sodium soap powder 3.0 Sodium tripolyphosphate 30.0 Sodium disilicate 9-0 Sodium perborate tetrahydrate 20.0 Tetraacetyethylenediamine (TAED) 3.0 Carboxymethy1 cellulose 1-0 Sodium sulphate light, enzymes to 100... 

Lochhead and Bray (1995) studied Eu3+ doped sodium disilicate glass with a high-pressure fluorescence line-narrowing technique. This technique was used to characterize the local structure of the Eu3+ ions up to a pressure of 21 GPa. For the crystal-field analysis they assumed a C2v site symmetry which allowed for a complete splitting of the crystal-field components. The crystal-field strength was determined according to eq. (11). The effect of pressure... 

Figure 9. Glow curves for the Sharps meteorite (type 3.4) before and after annealing at 755-855°C and 0.77-1 kbar for 168-174 h in the presence of water and sodium disilicate. (Reprinted by permission from Ref. 31. Copyright 1986 American Geophysical Union.)...

MLiquid phase formed at the sodium disilicate-quartz interface above the eutectic melting temperature and worked its way outward. Perforation refers to when the outer sodium disilicate shells were no longer continuous. 

The endotherm that peaked at 651°C intensifies steadily with decreasing particle size, as is the case for the associated DTG peak. This endotherm represents increased formation of liquid phase with decreasing particle size. The enhanced weight loss, indicated by the DTG traces with decreasing particle size, does not coincide with the formation of detectable new crystalline phases in the coarse particle sizes, but does correspond to XRD detection of the formation of sodium disilicate in the fine particle size. Thus, decreasing particle size results in a significantly enhanced low temperature liquid phase attack on silica grains. 

Figure 4.2. Opposing effects on the Si relaxation time and peak width of adding paramagnetic MnO to sodium disilicate glass, from the data of Mortuza (1989).

Figure 7.26. Changes in the P MAS NMR spectrum of sodium disilicate glass with increasing additions of P2O5. At the lower concentrations the orthophosphate resonance at 15 ppm is progressively replaced by pyrophosphate at 2.5 ppm. At higher P2O5 concentrations the metaphosphate chain units (-16 ppm) are replaced by SiP207 units (- 33 to — 40 ppm).

Figure 9.6. A. H CRAMPS-MAS correlation spectrum of hydrated sodium disilicate glass showing projections in both dimensions. B. Slices through the CRAMPS dimension of spectrum (A) showing the separate spectra from the H2O resonance at 4.0 ppm (upper) and the OH resonance at 14.0 ppm (lower). Note that the different sideband distributions from the 2 protonated groups are clearly distinguishable. From Schaller and Sebald (1995), by permission of the copyright owner.

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