Dynamics of poly(oxyethylene) melts: Comparison of 13C nuclear magnetic resonance spin-lattice relaxation and dielectric relaxation as determined from simulations and experiments

1997 ◽  
Vol 106 (9) ◽  
pp. 3798-3805 ◽  
Author(s):  
Grant D. Smith ◽  
Do Y. Yoon ◽  
Charles G. Wade ◽  
Daniel O’Leary ◽  
Angela Chen ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Dielectric Relaxation ◽  
Lattice Relaxation ◽  
Spin Lattice Relaxation ◽  
Spin Lattice ◽  
13C Nuclear Magnetic Resonance ◽  
Resonance Spin ◽  
Nuclear Magnetic

Solute 13C Nuclear Magnetic Resonance Spectrometric Investigation of Acetonitrile-Tetraalkylammonium Salt Interactions

1983 ◽  
Vol 37 (1) ◽  
pp. 29-31
Author(s):  
Neal R. Dando ◽  
Harvey S. Gold ◽  
Cecil Dybowski
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Salt Concentration ◽  
Alkyl Chain ◽  
Lattice Relaxation ◽  
Lattice Relaxation Time ◽  
Spin Lattice Relaxation ◽  
Spin Lattice ◽  
13C Nuclear Magnetic Resonance ◽  
Nuclear Magnetic

Carbon-13 nuclear magnetic resonance spectrometry is used to observe changes in the spin-lattice relaxation time ( T1) of the alkyl chain carbons of symmetric tetraalkylammonium salts ( R4N+) X− in acetonitrile as a function of salt concentration in the range from 0.25 to 1.4 M. The T1 values of the alkyl chain carbons are observed to be differentially sensitive to salt concentration, the sensitivity being greatest at the α carbon position. These observations suggest accessibility of the cation nitrogen to solvent molecules and changing microviscosity about the salt molecule.

scholarly journals Imaging of nuclear magnetic resonance spin–lattice relaxation activation energy in cartilage

2018 ◽  
Vol 5 (7) ◽  
pp. 180221 ◽  
Author(s):  
R. J. Foster ◽  
R. A. Damion ◽  
M. E. Ries ◽  
S. W. Smye ◽  
D. G. McGonagle ◽  
...  
Keyword(s):  
Activation Energy ◽  
Nuclear Magnetic Resonance ◽  
Relaxation Time ◽  
Magnetic Resonance ◽  
Lattice Relaxation ◽  
Spin Lattice Relaxation ◽  
Cartilage Tissue ◽  
Spin Lattice ◽  
Resonance Spin ◽  
Nuclear Magnetic

Samples of human and bovine cartilage have been examined using magnetic resonance imaging to determine the proton nuclear magnetic resonance spin–lattice relaxation time, T 1 , as a function of depth within through the cartilage tissue. T 1 was measured at five to seven temperatures between 8 and 38°C. From this, it is shown that the T 1 relaxation time is well described by Arrhenius-type behaviour and the activation energy of the relaxation process is quantified. The activation energy within the cartilage is approximately 11 ± 2 kJ mol −1 with this notably being less than that for both pure water (16.6 ± 0.4 kJ mol −1 ) and the phosphate-buffered solution in which the cartilage was immersed (14.7 ± 1.0 kJ mol −1 ). It is shown that this activation energy increases as a function of depth in the cartilage. It is known that cartilage composition varies with depth, and hence, these results have been interpreted in terms of the structure within the cartilage tissue and the association of the water with the macromolecular constituents of the cartilage.

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