Chemiluminescent Dosimetry of Microwave Heating and Acoustic Irradiations Based on Luminol and Metal Oxide Catalysts

Solutions of luminol, hydrogen peroxide, and sodium hydroxide containing trace amounts of various metal oxide catalysts were examined for chemiluminescent sensitivity to both heating and acoustic irradiations. It was found that a system containing copper(II) produced the largest relative change in luminescence as a result of heating, where I/ I o increased about 35-fold during a 40°C temperature increase beginning at 5°C. In contrast, a system catalyzed by scandium(III) was much less affected by heating but produced an immediate 2.5-fold luminescence increase in sonic irradiations at 5°C. These systems may have applications as chemiluminescent imaging dosimeters for distinguishing the heating and acoustic effects which occur when energetic pulses of microwave radiation are absorbed by material objects. Most of the metal-based dosimeters which were tried either reacted too rapidly or exhibited a weak temperature dependence, and a dosimeter based on luminol diazonium ion expended itself in seconds.