Galvosas Petrik, Callaghan Paul T
MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, New Zealand.
J Magn Reson. 2006 Jul;181(1):119-25. doi: 10.1016/j.jmr.2006.03.020. Epub 2006 Apr 27.
We here demonstrate the use of NMR velocity imaging techniques to measure flow in a free falling jet of water at speeds up to and on the order of 1m/s. In particular, we show how to adapt the RARE imaging method, based on a CPMG multiple rf pulse train, so that the real and imaginary parts of the signal may be suitably acquired, enabling pulsed gradient spin echo encoding for flow. We term this method "soft-pulse-quadrature-cycled PGSE-RARE" or SPQC-PGSE-RARE. We further demonstrate the use of a one-dimensional (slice selective) imaging method which takes advantage of the cylindrical symmetry of the flow, and considerably shortens the image acquisition time.
我们在此展示了利用核磁共振速度成像技术来测量自由下落的水流，其速度可达1米/秒左右。具体而言，我们展示了如何基于CPMG多个射频脉冲序列来调整RARE成像方法，以便能够适当地采集信号的实部和虚部，从而实现用于流动的脉冲梯度自旋回波编码。我们将此方法称为“软脉冲正交循环PGSE - RARE”或SPQC - PGSE - RARE。我们还展示了一种利用流动的圆柱对称性的一维（切片选择性）成像方法的应用，该方法显著缩短了图像采集时间。
