Diffusion Selective Pulses
Diffusion Selective Pulses
复制标题
扩散选择性脉冲
DOI：
10.1021/acs.jpclett.9b03222
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Walls, Jamie D.
中科院分区：
文献类型：
--
作者：
Gong, Zhaoyuan;Walls, Jamie D.
自扩散系数D提供了关于分子物种及其环境的重要化学和物理信息，并且可以在平衡条件下使用核磁共振（NMR）常规测量。在核磁共振中，扩散系数的差异也可以用来抑制来自快扩散物种的信号，而不是来自慢扩散物种的信号。迄今为止，还没有一种方法可以选择性地抑制仅来自具有特定扩散系数的物种的信号。在这项工作中，扩散选择性脉冲被开发，选择性地抑制磁化仅从物种为hd =DSel。这是通过在脉冲场梯度之间交错的核磁共振弛豫选择脉冲来实现的，其中磁化的有效横向弛豫与d有关。实验演示了扩散选择脉冲在水和水/丙酮/二甲亚砜样品和在磁共振成像幻影。
The self-diffusion coefficient,D, provides important chemical and physical information about a molecular species and its environment, andDcan be routinely measured under equilibrium conditions using nuclear magnetic resonance (NMR). Differences in diffusion coefficients can also be exploited in NMR to suppress signals from fast diffusing species relative to slow diffusing species. To date, no method for selectively suppressing signals only from species with a particular diffusion coefficient has been presented. In this work, diffusion selective pulses are developed that selectively suppress the magnetization only from species for whichD=DSel. This is accomplished by interleaving NMR relaxation selective pulses between pulsed field gradients, where the effective transverse relaxation of the magnetization is related toD. Experimental demonstrations of diffusion selective pulses on water and water/acetone/dimethyl sulfoxide samples and on a magnetic resonance imaging phantom are presented.