中国物理B ›› 2009, Vol. 18 ›› Issue (11): 4797-4806.doi: 10.1088/1674-1056/18/11/032
蔡聪波1, 沈桂平2, 蔡淑惠2, 陈忠2
Shen Gui-Ping(沈桂平)a),Cai Cong-Bo(蔡聪波) b), Cai Shu-Hui(蔡淑惠)a)†, and Chen Zhong(陈忠)a)
摘要: A modified correlated spectroscopy (COSY) revamped with asymmetric Z-gradient echo detection sequence was designed to investigate the influence of diffusion behaviour on intermolecular double-quantum coherence signal attenuation during the pre-acquisition period. Theoretical formulas were deduced and experimental measurements and simulations were performed. It is found that the diffusion behaviour of intermolecular double-quantum coherence in the pre-acquisition period may be different from that of conventional single-quantum coherence, depending on the relative orientation of diffusion weighting gradients to coherence selection gradients. When the orientation of the diffusion weighting gradients is parallel or anti-parallel to the orientation of the coherence selection gradients, the diffusion is modulated by the distant dipolar field. This study is helpful for understanding the signal properties in intermolecular double-quantum coherence magnetic resonance imaging.
中图分类号: (Self-diffusion and ionic conduction in nonmetals)