Bloch方程的解析解及其在水峰抑制和特形脉冲设计中的应用

波谱学杂志 ›› 1996, Vol. 13 ›› Issue (2): 153-162.

Bloch方程的解析解及其在水峰抑制和特形脉冲设计中的应用

黄永仁¹, 许峰¹, 李延安¹, 吴先球¹, 孔祥铭²

1. 上海华东师范大学分析测试中心, 上海 200062;
2. 上海石油化工研究院, 上海 201208

收稿日期:1995-07-10 修回日期:1995-08-07 出版日期:1996-04-05 发布日期:2018-01-17
基金资助:
国家自然科学基金与高校博士点基金资助项目

THE ANALYTICAL SOLUTIONS OF BLOCH EQUATIONS AND THEIR APPLICATION IN SOLVENT PEAK SUPPRESSION AND SHAPED PULSE DESIGN

Huang Yongren¹, Xu Feng¹, Li Yanan¹, Wu Xianqiu¹, Kong Xiangming²

1. NMR Lab & Analystical, Center:East China Normal University, Shanghai 200062;
2. Shanghai Petrochemical Research Institute, Shanghai 201208

Received:1995-07-10 Revised:1995-08-07 Online:1996-04-05 Published:2018-01-17

摘要/Abstract

摘要： 用Laplace变换方法求出了Bloch方程在各种不同物理条件下的解析解,这些解析解物理图象清楚,便于分析,克服了数值解中的困难.解析解和相应的结论已用于水峰抑制和特形脉冲的设计.对于水峰抑制,本文指出抑制效果是有极限的,并给出了抑制效果的极限以及最佳抑制时间的近似计算公式.在特形脉冲的模拟过程中,我们发现只有同时考虑全部四类解析解,才能得到正确的模拟结果,另外,模拟还表明,要在保持激励频谱形状不变的条件下,得到不同倾倒角的脉冲必须改变激励脉冲的形状,相应实验的结果与我们给出的上述结论完全吻合。

关键词: Bloch方程解析解, 水峰抑制, 特形脉冲

Abstract: In this paper, the analytical solutions of Bloch equations under various physical conditions are given by means of Laplace transformation.Those solutions have clear physical pictures and are easy to be used.They have ban put in the use of the solvent peak suppression and Shaped pulse design.About solvent peak suppression,the approximate formulae of suppression efficiency's limit and optimum suppression time are given.In design of Shaped pulse,we think that all four kinds of solutions in Bloch equations have to be taken into account.It is also shown by simulation that if the same frequency function excited by pulses for different flip angles are required,the shape of pulses in time domain must be modified. A series of experimental results coincide well with the above conclusions.

Key words: Analytical solutions of the Bloch equations, Solvent peak suppression, Shaped pulse

黄永仁, 许峰, 李延安, 吴先球, 孔祥铭. Bloch方程的解析解及其在水峰抑制和特形脉冲设计中的应用[J]. 波谱学杂志, 1996, 13(2): 153-162.

Huang Yongren, Xu Feng, Li Yanan, Wu Xianqiu, Kong Xiangming. THE ANALYTICAL SOLUTIONS OF BLOCH EQUATIONS AND THEIR APPLICATION IN SOLVENT PEAK SUPPRESSION AND SHAPED PULSE DESIGN[J]. Chinese Journal of Magnetic Resonance, 1996, 13(2): 153-162.

[1]	沙沂, 李文, 李宁, 肖皖. 双黄连口服液¹H NMR质量稳定性分析方法研究[J]. 波谱学杂志, 2011, 28(3): 366-373.
[2]	吴先球, 边明华, 张惠平, 邬学文. 特形脉冲调制中射频泄漏的影响及其补偿[J]. 波谱学杂志, 1996, 13(3): 259-266,276.
[3]	丁广良, 李丽云, 孟庆安, 叶朝辉. 脉冲形状对定域谱中水峰抑制作用的影响[J]. 波谱学杂志, 1995, 12(6): 573-579.
[4]	周进元, 李丽云, 叶朝辉. 特形脉冲的欧拉角[J]. 波谱学杂志, 1994, 11(4): 345-351.
[5]	张卫国. 体内¹H NMR中的水峰抑制[J]. 波谱学杂志, 1989, 6(4): 513-516.