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本文将基本的谱编辑脉冲序列与消旋转边带的TOSS脉冲序列联用,可以实现强磁场下13CCP/MAS谱编辑.通常,固体中非质子化碳与甲基碳的自旋晶格弛豫时间差别很大,此差别可作为谱编辑过程中区分它们的一条附加判据.对具有复杂分子结构的体系,此判据的作用尤其重要.文中的实例将表明:一个完整的13CCP/MAS谱编辑一般可通过SCPTOSS谱(短接触时间交叉极化谱);SCPPITOSS(短接触时间交叉极化极化反转)谱,LCPDTOSS(长接触时间交叉极化及去极化)谱及部分弛豫的LCPDTOSS谱适当组合而得到.
In this paper, the basic spectral editing pulse sequences are combined with the TOSS pulse sequences of revolving sidebands, which can realize 13CCP / MAS spectrum editing under strong magnetic field. In general, spin-lattice relaxation times for unprotonated carbon and methyl carbon in solids vary widely, and this difference can be used as an additional criterion for distinguishing them during spectral editing. The role of this criterion is especially important for systems with complex molecular structures. The examples in this paper show that a complete 13CCP / MAS spectrum can be edited by the SCPTOSS spectrum (short contact time cross polarization spectroscopy), SCPPITOSS (short contact time cross polarization reversal), LCPDTOSS Polarized and depolarized) spectra and the partially relaxed LCPDTOSS spectra.