Foley I, Farooqui SA, Kleinberg RL
Schlumberger-Doll Research, Ridgefield, Connecticut, 06877
J Magn Reson A. 1996 Nov;123(1):95-104. doi: 10.1006/jmra.1996.0218.
Proton NMR longitudinal and transverse relaxation times of water-saturated powder packs have been measured. The powders were a series of synthetic calcium silicates with known concentrations of iron or manganese paramagnetic ions. The rate of water proton relaxation has been found to be linearly proportional to the concentration of paramagnetic ion. The constant of proportionality is used to determine the electron relaxation time of ions at the fluid-solid interface. A substantial relaxivity is found in the absence of paramagnetic ions. Thus the oxide surface itself is an unexpectedly good relaxer of fluid-borne nuclear spins. The results answer some long-standing questions connected with the NMR properties of fluid-saturated sedimentary rocks.
已测量了水饱和粉末包的质子核磁共振纵向和横向弛豫时间。这些粉末是一系列含有已知浓度铁或锰顺磁离子的合成硅酸钙。已发现水质子弛豫速率与顺磁离子浓度呈线性比例关系。比例常数用于确定流体 - 固体界面处离子的电子弛豫时间。在没有顺磁离子的情况下发现了相当大的弛豫率。因此，氧化物表面本身是流体携带核自旋的意外良好弛豫剂。这些结果回答了一些与流体饱和沉积岩的核磁共振特性相关的长期问题。
