Analyses of the spin-lattice relaxation time ([T.sub.1]) and the spin-spin relaxation
time ([T.sub.2]) at different concentrations of the molecule (Figure 1(d)) suggest a [T.sub.1] of ~450 ms and [T.sub.2]s, which show significant shortening with increasing concentration.
The spin-lattice ([T.sub.1]) relaxation involves the transfer of energy between the spin system and the environment, and spin-spin relaxation
([T.sub.2]) processes involve the dephasing of nuclear spins, which are entropic processes .
In addition, the reduction of the spin-spin relaxation
times ([T.sub.2]) was observed from the lowest to highest concentrations, in which the signal intensity of the [T.sub.2]-weighted images decreased.
Mariette, "NMR study of tomato pericarp tissue by spin-spin relaxation
and water self-diffusion," Appl.
To further increase S/N and verify the impact of nuclear spin-spin relaxation
rate on spectral shape, the Carr-Purcell-Meiboom-Gill (CPMG) multiecho pulse sequence  was applied where all generated echoes in the train were recorded, and coherent summation of selected echoes was done.
time [T.sub.1[rho]] was determined by measuring spin echoes (90[degrees]x - T - 180[degrees]y) under spin lock condition, with T sampling in the range of 60 [micro]s to 1 ms.
T2 is termed spin-spin relaxation
time and is the release of energy through the hydrogen elements in close proximity.
The technique employed in this study uses differences in proton spin-spin relaxation
times of polymer and oil phases to determine the amount of oil in the oil-extended rubber.
where [I.sub.i] is the signal intensity of the [i.sup.th] proton spin group, which is directly proportional to its equilibrium magnetization, and [T.sub.2i] is the spin-spin relaxation
time of this group.
In this article, the physical properties of compounds using WMB are compared with dry-mixing compounds, and the characteristics of WMB are investigated by means of the spin-spin relaxation
time, the fracture surface energy and the dynamic creep.
(1) [Mathematical Expression Omitted] [T.sub.1] = spin-lattice relaxation time; [T.sub.2] = spin-spin relaxation
time; [[tau].sub.c] reorientational correlation time; eQ = electrical quadrupole moment; eq = gradient of the electrical field at the nucleus; K is a constant factor; and h = Planck's constant.
The [T.sub.2](spin-spin relaxation
time) value was determined by the CPMG (Carr-Purcell-Melboom-Gill) spin echo method (12, 13) at room temperature.