McClean V E, Sheppard R J, Grant E H
J Microw Power. 1981 Mar;16(1):1-7. doi: 10.1080/16070658.1981.11689216.
Calculations have been performed concerning the deposition of microwave energy in bound water surrounding a biological macromolecule immersed in a continuum consisting of free water and dissolved ions. In particular a previous model of a hydrated macromolecule has been generalised to one where the relaxation frequency of the bound water varies across the layer, and the calculations have been carried out for three combinations of values of ionic conductivity of the bound water and the continuum. When these conductivities are equal, but low, the average energy deposition per unit volume in the bound water is greater, sometimes by at least an order of magnitude, than that in the continuum at frequencies in the region of hundreds of MHz to a few GHz. As the ionic conductivity increases this effect decreases and at conductivities equal to that of physiological saline the specific energy deposition in the bound water is not more than around twice that in the surrounding electrolyte continuum over this frequency range. Therefore, for tissues of high bound water content exposed to microwaves of a given power density the biological effect produced is enhanced. For a biological tissue of high ionic conductivity with 20% of its water in the bound state the overall energy absorption would be 25% greater at certain frequencies than if all the water were in the free state. For materials of low ionic conductivity the increase would be more than one order of magnitude.
针对浸没在由自由水和溶解离子组成的连续介质中的生物大分子周围结合水内微波能量的沉积情况进行了计算。具体而言，先前的水合大分子模型已被推广至结合水的弛豫频率在整个层中变化的模型，并针对结合水和连续介质的离子电导率的三种组合值进行了计算。当这些电导率相等但较低时，在数百兆赫兹至几吉赫兹的频率范围内，结合水单位体积内的平均能量沉积比连续介质中的平均能量沉积更大，有时至少大一个数量级。随着离子电导率增加，这种效应减弱，当电导率等于生理盐水的电导率时，在该频率范围内结合水内的比能量沉积不超过周围电解质连续介质中的比能量沉积的两倍左右。因此，对于暴露于给定功率密度微波下的高结合水含量组织，所产生的生物效应会增强。对于具有20%结合态水的高离子电导率生物组织，在某些频率下的总能量吸收将比所有水均处于自由态时高25%。对于低离子电导率的材料，增加幅度将超过一个数量级。
