GENERALIZED RECIPROCITY

广义互惠

• 批准号: 6121036
• 负责人: ERIK K INSKO
• 金额: $ 1.35万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-30 至 1999-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6121036
• 关键词: biomedical resource; magnetic resonance imaging; radiology; statistics /biometry; technology /technique

The theory of reciprocity as described by Hoult may be generalized to account for the near, intermediate and radiation zone fields of the magnetic dipole. This form of reciprocity is important where the wavelength of the NMR signal is not large compared to the distance scale of the system. In these situations the effects of interference may be significant. In addition, both the frequency dependence and distance dependence of the NMR signal are altered. In general, the distance dependence of the signal may follow a 1/r3, 1/r2 or a 1/r dependence and the signal may be proportional to w, w2 or w3. Finally, the signal will reflect the full vector field nature of the magnetic dipole. The mathematical expression of the generalized reciprocity is equivalent to that of Hoult if the appropriate retarded potential form of the magnetic field is utilized.

霍尔特描述的互惠理论可以推广 考虑近区、中区和辐射区场 磁偶极子。 这种互惠形式很重要，因为 核磁共振信号的波长与距离相比并不大 系统的规模。 在这些情况下，干扰的影响 可能很重要。 此外，频率依赖性和 NMR 信号的距离依赖性发生改变。 一般来说， 信号的距离依赖性可能遵循 1/r3、1/r2 或 1/r 相关性并且信号可以与w、w2或w3成比例。 最后，信号将反映全矢量场性质 磁偶极子。 广义的数学表达式 如果适当的延迟，则互易性相当于霍尔特的互易性 利用磁场的势形式。