From helping to solve historical criminal cases to determining the fate of a disappearing beach in Jamaica and the air quality at your gym: neutron activation is an established method to find out the composition and origin of materials.
从帮助解决历史犯罪案件到确定牙买加海滩消失的原因或健身房的空气质量：中子活化是一种确定材料成分和来源的方法。原子能机构开发的一种电子学习工具正在帮助40个国家的研究人员应用这种方法。
中子活化是一种常见类型的分析，在全世界238座在运研究堆中有大约一半都在进行这种分析，还有一些加速器中子源也在做此类分析。这种高灵敏度的技术可以在不干扰或破坏被分析材料的情况下显示百万原子中一个原子的浓度。它的精度比其他分析方法都精确，对于批量分析和研究独特且需要保持完整的材料特别有用。
这项技术的工作原理是用中子照射稳定原子，然后测量样品中元素的衰变或辐射。科学家利用这种技术区分塑料、金属、玻璃、土壤和空气颗粒等的化学特征。
“目前，这种方法的主要应用领域是环境科学、考古学、文化遗产以及法医学。” 原子能机构研究堆专家Nuno Pessoa Barradas说。“然而，这些领域的研究人员不一定有核物理学的背景，因此他们可能无法充分发挥这种技术的潜力。
为了弥合这一知识鸿沟并满足日益增长的需求，原子能机构通过其核科学技术领域核教育、培训和宣传计划的技术合作项目网络，设置了一个关于中子活化分析的电子学习课程。该工具于2017年底推出，既能满足新学员，又能满足高级专业人士的需求。
2018年10月，在线培训课程达到了一个里程碑式的目标，在有运行中研究堆的52个国家里，其中40个国家在不到一年时间内报名参加学习。有几家研究院所使用这个工具给员工及包括大学生在内的学生上课。
“我们面临着频繁的员工流动，新员工的培训非常耗时，尤其是在这样一个专业领域。”匈牙利能源研究中心的Katalin Gméling说。“电子学习材料提供了大量信息，可以培训新员工并更新高级员工的知识。”
中子活化于1935年由匈牙利出生的化学家George de Hevesy和德国-丹麦物理学家Hilde Levi发现，最初被用来作为测量稀土元素质量的有用工具。
在过去几十年里，这种方法还有其他几种用途，包括为历史刑事案件提供额外的证据。2013年，中子活化技术应用在胡须上，用来反驳丹麦贵族Tycho Brahe是由于汞中毒致死的说法。他的珍贵笔记被他的助手、主要嫌疑犯、数学家和天文学家Johannes Kepler继承，此人发现了行星运动规律。
最近，在牙买加珊瑚泉海滩大约有500卡车的沙子被盗之后，地方当局与国际环境和核科学中心合作，应用中子活化技术检测来自疑似被盗海滩的沙子的来源，为这个案件提供了额外的证据。
今天，中子活化还被用来研究和测试室内空气质量（例如在学校和健身中心），帮助确定空气中污染物的数量和来源。
2018年9月在原子能机构维也纳总部举办的一个讲习班上对中子活化分析电子学习工具进行了评审。Barradas说：“该工具旨在成为一本活生生的书，随着该领域的发展，它可以不断更新和扩充，包括不同的实验室协议和研究领域。”第一版修订计划于2019年初启动。
In order to bridge this knowledge gap and address a growing demand, the IAEA, through the technical cooperation project Networking for Nuclear Education, Training, and Outreach Programmes in Nuclear Science and Technology, designed an e-learning course on neutron activation analysis. Launched in late 2017, the tool caters to both newcomers and specialized, advanced professionals.
This month the online training course reached a landmark target, with participants in 40 of the 52 countries with operating research reactors signing up for it in less than a year. Several institutes use the tool in the education of staff and students, including at university level.
“We face frequent changes of employees and the training of new staff is quite time consuming, especially in such a specialized field,” said Katalin Gméling from the Hungarian Centre for Energy Research. “The e-learning material offers a great collection of information to train newcomers and refresh the knowledge of senior staff.”
Discovered in 1935 by Hungarian-born chemist George de Hevesy and German-Danish physicist Hilde Levi, neutron activation originally became a useful tool to measure the mass of rare earth elements.
In the last decades, the method found several other uses, including to provide additional evidence to historical criminal cases. In 2013, using a moustache hair as a starting point, neutron activation was used to disprove the theory that mercury poisoning killed Danish nobleman Tycho Brahe, whose valuable notes were inherited and explored by his assistant (and alleged prime suspect): mathematician and astronomer Johannes Kepler, the discoverer of planetary motion laws.
More recently, following the theft of an estimated five-hundred truckloads of beach sand from the Coral Springs beach in Jamaica, local authorities teamed up with the International Centre for Environmental and Nuclear Sciences to apply neutron activation to test the origin of sand in suspected receptor beaches, providing additional evidence to the case.
Today, neutron activation is a method used to research and test indoor air quality, for example at schools and fitness centres, by helping to determine the quantity and origin of pollutants in the air.
The neutron activation analysis e-learning tool was reviewed at a workshop last month at the IAEA headquarters in Vienna. “The tool is intended as a living book that can be constantly updated and extended as this field evolves to include different laboratory protocols and research areas,” Barradas said. The launch of a first revision is planned for early 2019.