NMR imaging, NMR diffraction and applications of pulsed gradient spin echoes in porous media
NMR imaging, NMR diffraction and applications of pulsed gradient spin echoes in porous media
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DOI：
10.1016/s0730-725x(96)00152-x
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发表时间：
1996-01-01
影响因子：
2.5
通讯作者：
Callaghan, PT
中科院分区：
文献类型：
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作者：
Callaghan, PT
曼斯菲尔德和格兰内尔首先将衍射思想引入核磁共振，在这里我们将“曼斯菲尔德（k 空间）衍射”与“扩散（q 空间）衍射”进行比较，注意到它们的相似之处和差异。扩散衍射概念对于阐明多孔介质中流体分子的脉冲梯度自旋回波核磁共振实验非常有帮助，并已成功应用 对于模型孤立孔隙（“单缝”情况）和定向无序互连孔隙玻璃（“粉末光栅”情况），该图基于 PGSE 实验具有散射类比的思想，其中波矢量 (q) 与梯度脉冲之间自旋随时间 D 的位移共轭。最近，该理论已扩展到允许壁弛豫效应 和有限梯度脉冲宽度效应。版权所有 (C) 1996 爱思唯尔科学公司。
Diffraction ideas were first introduced to NMR by Mansfield and Grannell, Here we compare ''Mansfield (k-space) diffraction'' with the ''diffusive (q-space) diffraction,'' noting their similarities and differences, The diffusive-diffraction concept is extremely helpful in elucidating the Pulsed Gradient Spin Echo NMR experiment for fluid molecules in porous media and has been applied successfully to the model isolated pore (the ''single slit'' case) and the orientationally disordered interconnected pore glass (the ''powder grating'' case), This picture is based on the idea that the PGSE experiment has a scattering analogy in which a wavevector (q) is conjugate to the displacement of the spins over the time, D, between the gradient pulses, Recently, the theory has been extended to allow for both wall relaxation effects and finite gradient pulse width effects. Copyright (C) 1996 Elsevier Science Inc.