Spectra silicon-29 NMR

Silicon-29 nmr spectra in both solids and solutions can be correlated... 

Lattice degradation from thermal or hydrothermal treatments also can be followed by NMR. Silicon-29 NMR spectra of calcined and steam-aged HY-type crystals are characterized by a single resonance between -108 ppm and-110 ppm attributed mainly to the presence of Si[OAl] units generated by dealumination [22], In Figure 8 there is an additional weak and broad shoulder near -115 ppm. For HY crystals (with % Na20 between 0.9 and 1.0%), the relative signal intensity of the upfield resonance near -115 ppm increases with V-levels (Table... 

Silicon-29 NMR spectra can be used to identify isomers of trimethylsilylated 1,3-diborolanes (14) and (15) <94CB8I3>. 

Figure 5. Silicon-29 NMR spectra of (a) a silica gel derived from a solution with molar composition TMOS H2O HCl CH3OH of 1 1.53 0.4 2, (b) a silica gel derived from a solution with molar composition TMOS H2O HCl CH3OH of 1 1.53 0.01 2, and (c) silica particles derived from the solution with molar composition TMOS H2O NH3 CH3OH of 1 30 5 171.

Figure 6. Silicon-29 NMR spectra of gels prepared from solutions with mole ratios TMOS H2O HCl CH3OHofl 1.53 0.40 x, where x = 0.5, 2, 4, and 5.

Figure 5-10. Silicon-29 NMR spectra of (A) Silica gel, (B) TiO2 10SiO2 gel, and (C) Ti02 5Si02 gel calcined at 400 C C/2h in air.

Figure 5-11. Silicon-29 NMR spectra of a sample of thetic saonite (SUMECTON SA) before (A) and after pillaring with TiO2 10SiO2 clusters, followed (B) AD, (C) SCD, and (D) Steaming at 760 C/5h.

Fig. 5. Silicon-29 NMR spectra of 3-acryloxypropyltrimethoxysilane on silica (a) adsorbed and heated to 100°C and (b) after heating the sample in (a) to 600 C.

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