Boutis G S, Cappellaro P, Cho H, Ramanathan C, Cory D G
Department of Nuclear Engineering, Massachusetts Institute of Technology, NW14-2217, 150 Albany Street, Cambridge, MA 02139, USA.
J Magn Reson. 2003 Apr;161(2):132-7. doi: 10.1016/s1090-7807(03)00010-7.
We present improved line-narrowing sequences for dipolar coupled spin systems, based on a train of magic-echoes which are compensated for the effects of finite pulse widths and utilize symmetry properties of supercycles. Sequences are introduced for spectroscopy and imaging by proper choice of a phase alternating scheme. Using a 16 pulse time-suspension magic-echo cycle, the highest level of line-narrowing achieved was 2.7 Hz for the [100] direction of a single crystal of calcium fluoride, a reduction in linewidth by 4 orders of magnitude.
我们基于一系列魔回波，提出了用于偶极耦合自旋系统的改进型线窄化序列，这些魔回波可补偿有限脉冲宽度的影响，并利用超循环的对称特性。通过适当选择相位交替方案，引入了用于光谱学和成像的序列。使用16脉冲时间悬浮魔回波循环，对于氟化钙单晶的[100]方向，实现的最高线窄化水平为2.7 Hz，线宽降低了4个数量级。
