NNR IN RAPIDLY ROTATED METALS By - Nottingham eTheses ...

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results obtained at a temperature of 301 K in an applied field
of 1.45 T are listed in Table 7.2. The errors quoted refer only
TABLE 7.2. EXPERIMENTAL ZEEMAN AND DIPOLAR RELAXATION TIMES
POWDER SAMPLE
TjZ TID a
ms ms
99.995% pure sprayed (a) 6.12 ± 0.04 2.96 ± 0.05 2.07 ± 0.05
99.999% pure filed (c) 6.09 ± 0.04 2.88 ± 0.06 2.12 ± 0.06
99.5% pure sprayed (b) 6.04 ± 0.03 2.70 ± 0.05 2.24 ± 0.05
to the spread of values in each case and not to any possible instrun-
ental error or error in processing the data. The measurements were
recorded within a short space of time of each other and an accurate
comparison of the Tlz values could be made. Although the error
limits rule out any definite conclusion, the values quoted would
seem to indicate that the pure filed powder (c) had a slightly
shorter Tlz than that prepared by spraying pure wire. The short-
est Tlz values occurred for the sample (b) considered to be the
least pure of the three.
7.5.2 DIPOLAR RELAXATION TIME (TID)
The dipolar relaxation times of samples (a), (b) and (c)
were measured with the Jeener and Brockaert pulse sequence (see
Section 5.8) in identical conditions to those existing for the TlZ
measurements. The results are included in Table 7.2 together with