NMR 中非线性梯度场下扩散行为的理论描述和蒙特卡罗模拟

波谱学杂志

NMR 中非线性梯度场下扩散行为的理论描述和蒙特卡罗模拟

蔡聪波, 蔡淑惠, 陈忠*

厦门大学物理系，固体表面物理化学国家重点实验室，福建厦门 361005

收稿日期:2003-01-13 修回日期:2003-04-21 出版日期:2003-09-05 发布日期:2003-09-05
作者简介:*通讯联系人：陈忠，Tel:+86-592-2189426,Fax:+86-592-2189426,E-mail:Chenz@jingxian.xmu.edu.cn
基金资助:
Project Supported by the National Natural Science Foundation of China(10005006,10104011 and 10234070).

THEORETICAL EXPRESSION AND MONTE CARLO SIMULATION OF DIFFUSION BEHAVIORS IN NMR WITH NONLINEAR FIELD GRADIENTS

CAI Cong-bo, CAI Shu-hui, CHEN Zhong*

Department of Physics, State Key Laboratory for Physical Chemistry of the Solid Surface, Xiamen University, Xiamen 361005, China

Received:2003-01-13 Revised:2003-04-21 Online:2003-09-05 Published:2003-09-05
About author:Congbo Cai, male, born in Quangzhou, Fujian in (1975-), Ph.D.student, specializing in condensed physics. *Correspondence author: Chen Zhong, Tel: +86-592-2189426. Fax:+86-592-2189426. E-mail: chenz@jingxian.xmu.edu.cn
Supported by:
Project Supported by the National Natural Science Foundation of China(10005006,10104011 and 10234070).

摘要/Abstract

摘要：

利用传播子方法研究了在一般非线性场梯度下NMR信号的扩散衰减. 在自由扩散和平板间的限制扩散情况下获得了扩散衰减因子的理论表达式. 该表达式适用范围宽，且具有较简单的数学形式和明确的物理意义. 文中还将理论预测与蒙特卡罗模拟结果进行了比较. 结果表明：文中所采用的理论方法适合于表述自由扩散和短脉冲近似下的受限扩散；蒙特卡罗模拟提供了一种定性研究MRI和NMR中非均匀场梯度扩散衰减的方法.

关键词: 核磁共振, 非线性场梯度, 扩散, 模拟, 理论表述

Abstract:

A propagator method was used to calculate diffusion attenuation of the NMR signal under general nonlinear field gradients. Theoretical expressions of
the attenuation factor were obtained for free and restricted diffusion between two plates. Monte Carlo simulation was performed and the results were compared with the theory. It shows that the theoretical method is appropriate for the free diffusion, as well as the restricted diffusion under the short gradient pulse approximation. Monte Carlo simulation provides an alternate way to quantify the effects of inhomogeneous field gradients used in MRI and NMR.

Key words: NMR, Nonlinear gradient, Diffusion, Simulation, Theoretical expression

中图分类号:

O482.53

蔡聪波, 蔡淑惠, 陈忠*. NMR 中非线性梯度场下扩散行为的理论描述和蒙特卡罗模拟[J]. 波谱学杂志.

CAI Cong-bo, CAI Shu-hui, CHEN Zhong*. THEORETICAL EXPRESSION AND MONTE CARLO SIMULATION OF DIFFUSION BEHAVIORS IN NMR WITH NONLINEAR FIELD GRADIENTS[J]. Chinese Journal of Magnetic Resonance.

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