波谱学杂志 ›› 2010, Vol. 27 ›› Issue (3): 425-435.

• 液体及固体NMR • 上一篇    下一篇

周期性控制液态磁共振自旋湍流的研究

Susie Y. HUANG, Jamie D. WALLS, 林永雅*   

  1. 加州大学洛杉矶校区,化学与生物化学系,加利福尼亚州 90095,美国
  • 收稿日期:2010-07-16 出版日期:2010-09-05 发布日期:2010-09-05

Periodic Control of Spin Turbulence in Solution Magnetic Resonance

 Susie Y. HUANG, Jamie D. WALLS, LIN Yung-Ya   

  1. Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA
  • Received:2010-07-16 Online:2010-09-05 Published:2010-09-05

摘要:

辐射阻尼和远程偶极场联合作用导致的混沌自旋动态能够产生常见于高场梯度磁共振实验中不可再现的实验结果,且该现象较先前所认为的更为常见. 该文发展了一种基于射频微扰的周期性控制方法,以降低Lyapunov指数并抑制在波谱中的不稳定测量结果. 同时讨论了周期性控制的设计原则及如何应用在诸多脉冲序列中, 用以抑制自旋湍流.

关键词: 暂态性自旋湍流, 辐射阻尼, 远程偶极场, 混沌控制, 信号放大

Abstract:

Chaotic spin dynamics arising from the joint action of radiation damping and the distant dipolar field are shown to generate irreproducible measurements in popular high-field gradient magnetic resonance experiments, a phenomenon more general than previously thought. A periodic control scheme based on radio-frequency perturbations is developed that decreases the leading Lyapunov exponent and reduces observed fluctuations to within intrinsic spectrometer instability. General guidelines for designing and integrating such schemes into existing pulse sequences to suppress spin chaos are discussed.

Key words: transient spin chaos, radiation damping, distant dipolar field, chaos control, signal amplification

中图分类号: