摘要
该文从经典电动力学的玻印廷矢量和麦克斯韦场方程推导出了人体组织比吸收率的一般表达式 ,根据表达式中三个基本的复数电磁参量在不同生物组织、不同频率下的可能取值 ,讨论了三个复数电磁参量对生物组织比吸收率的影响。结果表明 ,在非磁性组织中 ,当f<0 .5GHz时 ,电磁损耗主要是组织电导率决定的 ;当f>0 .5GHz时 ,随频率升高介电损耗变得更为重要。某些人体组织 (如脑组织 )中含有微小的磁性物质 ,通过估算发现这些磁性体的比吸收率是周围非磁性组织的 4 0 0多倍。
The general formula of human tissues specific absorption rate is derived from the classical electrodynamics, this involves the Pointing vector and Maxwell equation. Three complex electromagnetic constitutive parameters have different values in different human tissues at different frequencies. By analysis we find: The specific absorption rate (SAR) can be roughly 400 fold greater in a magnetosome than in the background nonmagnetic tissue surrounding it. In nonmagnetic tissues, The chief physical loss mechanism will be ionic conduction while f < 0.5 GHz; The dielectric relaxation loss become important as the frequency rises.
出处
《华东师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2002年第3期42-46,共5页
Journal of East China Normal University(Natural Science)
基金
上海科技发展基金 (OOJC14 0 17)
上海市重点学科项目资助
