WAW and SAW Bound in Bone Tissue

Fignre 7.53 shows the H NMR spectra of water in sample I in air and deuterochloroform. The spectra inclnde two signals, one of which (signal 1) has chemical shift 5h=4-5 ppm, and the second (signal 2) 5e=1.4-1.7 ppm. The intensity of signal 1 more strongly decreases because of partial 

FIGURE 7.53 H NMR spectra of water in partially hydrated bones at different temperatures in (a) air and (b) CDCI3. (Adapted from Colloids Surf. B Biointerfaces, 48, Turov, V.V., Gun ko, V.M., Zarko, V.I. et al.. Weakly and strongly associated nonfreezable water bound in bones, 167-175, 2006a, Copyright 2006, with permission from Elsevier.) 

Quantum chemical calculations (with consideration of the effects of a solvent) of water clusters (HjO) at = 1, 2,4, 6 in cyclohexene (as a model nonpolar medium) show that the free energy of solvation is minimal for a dimmer in which 75% of protons do not participate in the hydrogen bonds and 8h=0.8-1.9 ppm corresponding to signal 2. These calculations show a possible reason for the appearance of the aforementioned signal for bone tissue. 

Nuclear Magnetic Resonance Studies of Interfacial Phenomena 

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