Shigemitsu T, Takeshita K, Shiga Y, Kato M
Central Research Institute of Electric Power Industry, Tokyo, Japan.
Bioelectromagnetics. 1993;14(2):107-16. doi: 10.1002/bem.2250140204.
The design, construction, and results of evaluation of an animal-exposure system for the study of biological effects of extremely low frequency (ELF) magnetic fields are described. The system uses a square coil arrangement based on a modification of the Helmholtz coil. Due to the cubic configuration of this exposure system, horizontal and vertical magnetic fields as high as 0.3 mT can be generated. Circularly polarized magnetic fields can also be generated by changing the current and phase difference between two sets of coils. Tests were made for uniformity of the magnetic field, stray fields, sham-exposure ratio of stray field, changes of temperature and humidity, light intensity and distribution inside the animal-housing space, and noise due to air-conditioning equipment. Variation of the magnetic field was less than 2% inside the animal housing. The stray-field level inside the sham-exposure system is less than 2% of experimental exposure levels. The system can be used for simultaneous exposure of 48 rats (2 to a cage) or 96 mice (4 to a cage).
本文描述了一种用于研究极低频（ELF）磁场生物效应的动物暴露系统的设计、构建及评估结果。该系统采用基于亥姆霍兹线圈改进的方形线圈排列。由于此暴露系统的立方体结构，可产生高达0.3 mT的水平和垂直磁场。通过改变两组线圈之间的电流和相位差，还可产生圆极化磁场。对磁场均匀性、杂散场、杂散场的假暴露率、温度和湿度变化、动物饲养空间内的光强和分布以及空调设备产生的噪声进行了测试。动物饲养室内磁场变化小于2%。假暴露系统内的杂散场水平低于实验暴露水平的2%。该系统可用于同时暴露48只大鼠（每笼2只）或96只小鼠（每笼4只）。
