Malathi N, Sahoo P, Praveen K, Murali N
Innovative Instrumentation Section, Real Time Systems Division, Electronics Instrumentation and Radiological Safety Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102 Tamilnadu India.
J Radioanal Nucl Chem. 2013;298(2):963-972. doi: 10.1007/s10967-013-2531-x. Epub 2013 May 14.
The paper presents an innovative approach towards development of real time dosimetry using a chemical dosimeter for measurement of absorbed radiation dose in the range between 1 and 400 Gy. Saturated chloroform solution in water, a well known chemical dosimeter, is used to demonstrate the concept of online measurement of radiation dose. The measurement approach involves online monitoring of increase in conductivity of saturated chloroform solution due to progressive build up of traces of highly conducting HCl during exposure to gamma irradiation. A high performance pulsating sensor-based conductivity monitoring instrument has been used to monitor such real time change in conductivity of solution. A relation between conductivity shift and radiation dose has been established using radiochemical yield value ( value) of HCl. The value of HCl in saturated chloroform dosimeter has been determined using laboratory developed pulsating sensor-based devices. In this connection dose rate of Co-60 gamma chamber was determined using Fricke dosimeter following a simple potentiometric measurement approach developed in-house besides conventional spectrophotometry. Results obtained from both measurement approaches agreed well. Complete instrumentation package has also been developed to measure real time radiation dose. The proposed real time radiation dosimeter is successfully tested in several measurement campaigns in order to assure its performance prior to its deployment in field.
本文介绍了一种创新方法，用于开发一种使用化学剂量计的实时剂量测定法，以测量1至400 Gy范围内的吸收辐射剂量。水饱和氯仿溶液是一种众所周知的化学剂量计，用于演示辐射剂量在线测量的概念。测量方法包括在线监测饱和氯仿溶液的电导率增加，这是由于在伽马辐射暴露期间高导电性HCl痕迹的逐渐积累所致。一种基于高性能脉动传感器的电导率监测仪器已被用于监测溶液电导率的这种实时变化。利用HCl的放射化学产额值（ 值）建立了电导率变化与辐射剂量之间的关系。饱和氯仿剂量计中HCl的 值已使用实验室开发的基于脉动传感器的装置确定。在这方面，除了传统的分光光度法外，还采用了内部开发的简单电位测量方法，使用弗里克剂量计确定了Co-60伽马室的剂量率。两种测量方法得到的结果吻合良好。还开发了完整的仪器套件来测量实时辐射剂量。所提出的实时辐射剂量计在几次测量活动中成功进行了测试，以便在其部署到现场之前确保其性能。
