Computer Science
Scientific paper
Dec 2005
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005gecoa..69.5557m&link_type=abstract
Geochimica et Cosmochimica Acta, Volume 69, Issue 23, p. 5557-5566.
Computer Science
5
Scientific paper
Solubility mechanisms of water in depolymerized silicate melts quenched from high temperature (1000° 1300°C) at high pressure (0.8 2.0 GPa) have been examined in peralkaline melts in the system Na2O-SiO2-H2O with Raman and NMR spectroscopy. The Na/Si ratio of the melts ranged from 0.25 to 1. Water contents were varied from ˜3 mol% and ˜40 mol% (based on O = 1). Solution of water results in melt depolymerization where the rate of depolymerization with water content, ∂(NBO/Si)/∂XH2O, decreases with increasing total water content. At low water contents, the influence of H2O on the melt structure resembles that of adding alkali oxide. In water-rich melts, alkali oxides are more efficient melt depolymerizers than water. In highly polymerized melts, Si-OH bonds are formed by water reacting with bridging oxygen in Q4-species to form Q3 and Q2 species. In less polymerized melts, Si-OH bonds are formed when bridging oxygen in Q3-species react with water to form Q2-species. In addition, the presence of Na-OH complexes is inferred. Their importance appears to increase with Na/Si. This apparent increase in importance of Na-OH complexes with increasing Na/Si (which causes increasing degree of depolymerization of the anhydrous silicate melt) suggests that water is a less efficient depolymerizer of silicate melts, the more depolymerized the melt. This conclusion is consistent with recently published 1H and 29Si MAS NMR and 1H-29Si cross polarization NMR data.
Cody George D.
Mysen Bjorn O.
No associations
LandOfFree
Solution mechanisms of H2O in depolymerized peralkaline melts does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Solution mechanisms of H2O in depolymerized peralkaline melts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Solution mechanisms of H2O in depolymerized peralkaline melts will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1431983