NANOstructured Beta Detectors for Detection Of Tritium (NANODOT)

氚是氢的一种放射性同位素，由核裂变反应和对放射性废物的腐蚀、辐射分解和微生物过程产生。它通过平均动能5.7 keV的软β衰变衰变为He-3。这种低能量使得即使通过闪烁计数也很难检测到它。除其他外，需要对气态氚进行快速、准确和精确的测量：高放射性废物临时储存地点周围的环境监测和泄漏检测；为这些废物的地质储存库拟订环境安全案例；核反应堆、核燃料处理厂及其周围环境与安全监测；核取证，包括在反恐、国土安全和防扩散方面的应用。钯是一种表现出几乎独特的将H2吸收到其晶体基质中的能力的金属。市场上有许多基于氢与钯金属相互作用的商用H2传感器，其中大多数通过测量金属电容或电阻来量化这种吸收。迄今为止，还没有人探索过利用独特的Pd-H相互作用作为一种选择性地从气相样品基质中预先浓缩氚的手段的可能性，以便使用pd修饰的闪烁检测器改进其检测。因此，我们提出利用纳米材料合成中的新概念，使我们能够将纳米多孔钯层修饰的传感器/闪烁计数器与电离辐射事件的数字化数据捕获耦合起来，以开发一种基于辐射传感器的新型测量系统，用于气态氚检测。纳米多孔钯的使用将增加可用于氚吸收的金属的表面积，而数字化数据捕获的使用将允许捕获整个数据集，以供子孙后代和后处理。这两种措施都有望改善信噪比，有助于实现更低的检测极限，从而提高测量的准确性和精度。在为上述应用开发这种传感器时，建议的工作涉及以下NERC主题行动计划（TAPs）：技术；环境、污染与人类健康；自然灾害。我们的目标是通过技术准备5级（示范）来开发传感器系统。该项目是兰开斯特大学工程系和兰开斯特环境中心（LEC）以及兰开斯特衍生公司Hybrid Instruments之间的合作项目。国家核实验室（曾是该项目的前身项目的合作伙伴）和核退役管理局放射性废物管理理事会将是关键的最终用户。

Tritium is a radioactive isotope of hydrogen that is produced from nuclear fission reactions and from the action of corrosion, radiolytic and microbial processes on radioactive wastes. It decays to He-3 by soft beta decay of average kinetic energy 5.7 keV. This low energy makes it difficult to detect even by scintillation counting. Fast, accurate and precise measurement of gaseous tritium is required for, inter alia: environmental monitoring & leak detection around interim storage sites for higher level radioactive wastes; development of the environmental safety case for the geologic repository for those same wastes; environmental and safety monitoring in and around nuclear reactor and nuclear fuel processing plant; and nuclear forensics, including applications in counter-terrorism, homeland security and non-proliferation. Palladium is a metal that shows an almost unique capacity for absorbing H2 into its crystal matrix. There are a number of commercial H2 sensors on the market based on the interaction of H with palladium metal, most of which quantify this uptake by measurement of the metal capacitance or resistance. No one to date has explored the possibility of exploiting the unique Pd-H interaction as a means to selectively preconcentrate tritium from gas phase sample matrices in order to improve its detection using a Pd-modified scintillation detector. We therefore propose to exploit new concepts in nanomaterials synthesis to allow us to couple nanoporous palladium layer-modified transducers / scintillation counters and digitized data capture from ionizing radiation events to develop a novel radiometric sensor-based measurement system for gaseous tritium detection. The use of nanoporous palladium will increase the surface area of metal available for tritium absorption whilst the use of digitised data capture will allow for whole data sets to be captured for posterity and post-processing. Both measures are expected to lead to improved signal to noise ratios assistive to the achieving of lower limits of detection and so greater accuracy and precision in measurement. In developing this sensor for the applications mentioned above , the proposed work addresses the following NERC Theme Action Plans (TAPs):Technologies; Environment, Pollution & Human Health; and natural Hazards. We aim to develop the sensor system through to Technology Readiness Level 5 (Demonstration). This project is a partnership between the Engineering Dept and the Lancaster Environment Centre (LEC) at Lancaster University and Hybrid Instruments, a Lancaster spin-out. The National Nuclear Laboratory (who have served as partners on predecessor projects to this), and the Nuclear Decommissioning Authority Radioactive Waste Management Directorate will be a key end user.