Sodium phosphate glass

Prabakar, S., Wenslow, R.M., and Mueller, K.T. (2000) Structural properties of sodium phosphate glasses from Na -> cross-polarization NMR./. Non-Cryst. Solids, 263, 82-93. 

Both zinc and iron sulfides have to be present in a mixed Fe/Zn polyphosphate matrix and iron sulfide is present in the more severe tribological conditions. The XANES analytical technique is considerably more chemically sensitive than XPS, and the degree of phosphate polymerization was quantified for sodium phosphate glasses (Fuller et al., 2002 Yin et al., 1995), zinc phosphate glasses (Kasrai et al., 1995), and the antiwear tribofilms. 

Gresch, R., W. Muller-Warmuth, and H. Dutz (1979). X-ray photoelectron spectroscopy of sodium phosphate glasses. J. Noncryst. Solids 34, 127-36. 

Figure 7.25. A. chemical shifts for a series of sodium phosphate glass compositions compared with those of known tetrahedral phosphate units. From Brow et al. (1990). B. P chemical shifts for a series of sodium lithium phosphate glasses as a function of the mixed alkali ratio.

A situation intermediate between the two extreme cases discussed above is found in sodium phosphate glasses [61]. Figure 19 shows experimental REDOR curves for two samples containing 60% and 35% sodium oxide. Since the... 

Fig. 19 Site resolved Pj Na REDOR results on two sodium phosphate glasses using the sequence of Fig 8b. The 180° solid pulse length for Na was 3.9 ps (top) and 5.5 ps (bottom). The REDOR curves were composed from measurements at two rotor frequencies (15 and 10 kHz, top figure and 15 and 12 kHz, bottom figure)...

If the calcium phosphate fibers grown from ultraphosphate melts are slurried with a solution of sodium ethylene diamine tartaric acid the calcium crystals can be converted to a sodium phosphate glass that dissolves very slowly yielding very long chains. 

Fig. 1. Average chain lengths of polyphosphates derived from glasses with various P/Si ratios (37). A Experimental values for the NaP0s-Na2Si03 system. B Experimental values for the NaP03-Si02 system. C Values calculated for the NaP03-Na2Si0s system assuming that there is no interaction between a sodium phosphate glass and silicon dioxide in a melted state.

Therefore, a sodium phosphate glass seems to react with silicon dioxide at a high temperature to form P-O-Si linkages. There are four types of... 

Figure 3 A 3ip 3ip homonuclear 2D J-resolved NMR spectrum of a dissolved sodium phosphate glass with n = 4.1 (shown at the bottom). The characteristic J-coupling for each species is observed, causing extensive overlap in the corresponding 1D spectrum shown at the top. The vast simplification obtained by projecting the 2D J-resolved spectrum vertically onto the chemical shift axis (middle spectrum) clearly delineates the effectively broadband decoupled resonances. All spectra were accumulated at 161.9MHz using a 5% (m/m) phosphate solution in H2O with a D2O insert for locking purposes.

Nitridation can improve the properties of sodium phosphate glasses (12.65). 

R.K. Brow, R.J. Kirckpatrick, G.L. Turner, The short range structure of sodium phosphate glasses I. MAS NMR studies,. Non-Cryst. Solids 116 (1990) 39-45. 

Anderson et al. have presented solid-state NMR analysis of local structural environments in phosphate glasses for educational purposes. " In particular, the solid-state NMR wide-line spectra of a series of sodium phosphate glasses have been considered, which can also be simulated by spectral addition of reference solid-state spectra obtained for pure pyrophosphate and metaphosphate salts. The example chosen introduces the principles of solid-state NMR and allows interpretation of the spectrum in terms of the composition and localised phosphate environment. 

R. V.S.S.N. Ravikumar, V. Rajagopal Reddy, A.V. Chandrasekhar, B.J. Reddy, Y.P. Reddy, P.S. Rao, Tetragonal site of transition metal ions doped sodium phosphate glasses. 1. Alloys Compd. 337(1-2), 272-276 (2002)... 

G. Concas, F. Congiu, E. Manca, C. Muntoni, G. Pinna, Mossbauer spectroscopic investigation of some iron-containing sodium phosphate glasses. J. Non-Cryst. Solids 192-193, 175-178... 

Synonyms Glassy sodium Graham s salt Hexametaphosphate sodium salt Hexa-sodium metaphosphate HMP Metaphosphoric acid, hexasodium salt Phosphate, sodium hexameta- SHMP Sodium phosphate glass Sodium polymetaphosphate Classification Inorganic salt Ionic Nature Anionic Empirical O jPg 6Na Formula (NaPOjjg... 

Hall A, Swenson J, Adams S, Meneghini C (2008) Mixed mobile Irai effect and coopraative motions in silver-sodium phosphate glasses. Phys Rev Lett 101 195901... 

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