波谱学杂志

• 研究论文 • 上一篇    下一篇

在辐射阻尼存在下有效横向弛豫时间T*2的快速测定

罗会俊   

  1. 华东理工大学分析测试中心,上海 200237
  • 收稿日期:2001-01-08 出版日期:2001-03-05 发布日期:2001-03-05
  • 作者简介:罗会俊(1969-),男,硕士,讲师.

THE MEASURREMENT OF THE EFFECTIVE TRANSVERSE RELAXATION TIME IN THE PRESENCE OF RADIATION DAMPING

LUO Hui-jun   

  1. Analysis and Research Center, East China University of Science and Techn ology, Shanghai 200237
  • Received:2001-01-08 Online:2001-03-05 Published:2001-03-05

摘要:

利用CPMG自旋回波技术,通过一连串180°脉冲抑制辐射阻尼效应,让磁化矢量经过横向弛豫T2过程大幅度衰减后再检测回波信号的线宽,该方法可直接获得有效横向弛豫时间T*2,并可在CPMG测试T2值的同时进行.  另外,当饱和恢复法用于估计T*2值时,信号检测必须使用小角度脉冲.所有结果已进行了实验验证.

关键词: NMR, 辐射阻尼, CPMG, 饱和恢复, T*2

Abstract:

A new procedure for measuring the effective transverse relaxation time T*2 in the presence of radiation damping is proposed here. After the amplitude of the echo obtained by CPMG pulse sequence is largely decayed by the intrinsic T2 relaxation process, its linewidth is no longer broadened by the radiation da
mping effect and thus a good measure of the true value of T*2 is possible. Accordingly, for the damped case, the T*2 and T2 can in fact be simultaneously determined in a CPMG spin-echo experiment. In addition, when the saturation recovery experiment was utilized to measure T*2, the small-flip-angle pulse must be applied to detect the signals.

Key words:

very, NMR


中图分类号: