| 摘要 |
Radio-frequency (RF) heating is used to accelerate the thermal equilibration of dielectrically lossy nuclear magnetic resonance (NMR) samples. High-power heating RF pulses are applied to the sample before lower-power measurement RF pulses, using any of the NMR probe coils. The heating pulses are offset in frequency relative to the measurement pulses, such that the heating pulses do not magnetically affect the spins of interest. Heating pulse sequences of decreasing power can be used to prevent the sample temperature from overshooting the desired equilibrium temperature. Heating RF pulses can pre-establish the thermal effects of both measurement-independent and measurement-dependent heating. For pre-establishing the thermal effects of measurement-dependent heating, the heating pulse transients are chosen to be proportional to subsequent measurement pulse transients.
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