| 摘要 |
In a method of heteronuclear decoupling in a pulsed nuclear magnetic resonance spectroscopy method operating at high resolution, an interfering nuclear species (e.g. protons) is irradiated by means of a number of composite pulses (R1, R2, R1, R2 etc.), each of which virtually inverts the longitudinal magnetisation, during the generation of signals originating from a nuclear species (e.g. carbon 13) to be observed. Two types of pulses (R1, R2 etc. and R1, R2 etc.) are used which have opposite high-frequency phases and the pulse series forms a repetitive train composed of 2<N> pulses of each type (where N is a positive integer), the pulse series having a form which is chosen in accordance with specific rules in order to ensure an effective decoupling. In a preferred form, the composite pulses are each composed of three individual pulses having a suitable duration, between which negligible intervals are present, the first and the third pulse having the same high-frequency phase, which differs from that of the second pulse by 90 DEG .
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