H-1-NMR OF WATER INFLUENCED BY SUSPENDED MAGNETIC PARTICLES

被引：4

作者：

JANG, EK ^{[1
]}

YU, I ^{[1
]}

机构：

[1] SEOUL NATL UNIV,DEPT PHYS,SEOUL 151742,SOUTH KOREA

来源：

COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS | 1993年 / 72卷

关键词：

MAGNETIC FIELD GRADIENT; MAGNETIC SUSPENSION; RESONANCE SHIFT; SPIN RELAXATIONS;

D O I：

10.1016/0927-7757(93)80471-P

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Spin-lattice and spin-spin relaxation times of H-1 in aqueous suspensions are measured as functions of the concentrations of suspended alpha-Fe2O3 and Fe3O4 particles. The spin-lattice relaxation time T1 decreases strongly as the concentrations of magnetic particles are increased. Systematic deviations from the Bloembergen-Purcell-Pound (Phys. Rev., 73 (1948) 679) theory of spin relaxations in liquid samples are observed and attributed to the correlation effects of the magnetic particles. The decay-time measurements of the stimulated echo envelope indicate the presence of a magnetic field gradient which is dependent on the magnetic particle concentrations. We also observe large resonance frequency shifts in the Fe3O4 suspensions and the shifts are almost proportional to the particle concentration. The local inhomogeneous magnetic fields produced by the moments of the magnetic particles are responsible for the observed field gradient and frequency shift.

引用

页码：229 / 236

页数：8

共 20 条

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[2]

[Anonymous], 1971, PULSE FOURIER TRANSF

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