Nuclear magnetic resonance of alkali elements is a very sensitive probe of the immediate chemical environment of an alkali ion in solutions and can be used to study ion-ion, ion-solvent and ionligand interactions. In particular, this technique has been used to determine contact ion pair formation constants, to compare solvating abilities of different solvents and to study the thermodynamics of ...

The quantitation of intracellular sodium ion concentration [Na+]in perfused organs using NMR spectroscopy requires a knowledge of the extent of visibility of the 23Na resonance and of the intracellular volume of the organ. We have used a multinuclear NMR approach, in combination with the extracellular shift reagent dysprosium (III) tripolyphosphate, to determine the NMR visibility of intra- and...

Biomedical investigations with small animals using 0.5-T and 7-T MRI scanners adjusted on the Larmor frequencies of different nuclei 1H, 2H, 11B, 13C, 19F, 23Na, 31P, 35Cl are described. Experiments on registration of signals 19F from the fluorocarbons injected in laboratory animals are discussed. They give presentation on the application of fluorocarbon compounds as blood substitutes and contr...

Two NMR techniques, zH MAS NMR and echo Fourier 27AI NMR, have been applied for the first time to the investigation of Bronsted sites in dehydrated hydrogen forms ofzeolites. The “AI signal of SiOHAl sites, which was “NMR-invisible” until now, yields a quadrupole coupling constant C,,= 16 MHz for the dehydrated zeolite H-ZSM-5. The values of C,, determined from the ZH MAS NMR spectra of SiODAl ...

The utility of interleaved odd-number leg birdcage coils is demonstrated for decoupling in double- and triple-tuned multinuclear applications. was designed to geometrically decouple from a planar double-tuned (1H-23Na) array 31P saddle coil insert create configuration. Comparisons between an actively detuned purely decoupled architecture were used demonstrate the capabilities design. In particu...

The solvent-free (SF) synthesis is a green alternative to the conventional method of for zeolites. In this study, we show first time feasibility carrying out SF silicalite-1 (F? route) without any grinding. We also monitor changes during thanks multiple characterization techniques: XRD, TGA, SEM, EDX, and multinuclear NMR (13C, 19F, 29Si). how duration thermal treatment impacts zeolite crystal ...