Compact, deadtime-free, stray-field NMR sensor

杂散场核磁共振是一种在实验室中进行无损材料检测的技术。它在科学界和工业界都有很好的基础。主要应用于聚合物和相关材料的质量控制和老化，包括PE管道，PVC地板，汽车轮胎，沥青路面，人体皮肤和食品。在许多情况下，这些材料可以通过Magritek和Bruker等供应商的商业实验室技术进行维护。然而，电流传感器的死区时间太长，不适合用于电化学分析。G.水泥等建筑材料中的结合水、风车翅膀中的玻璃纤维和碳纤维增强聚合物复合材料以及绘画和乐器上的清漆。此外，改进设备，使之能在偏远地区和恶劣环境条件下工作，并查明核磁共振弛豫/扩散与应用参数之间的相关关系，将大大有助于有形文化遗产分析和户外测量等新出现的应用。该项目的主要科学目标是实现紧凑型杂散场NMR传感器的死区时间从目前的70 µs大幅减少到10 mm深度时的20 µs以下。此外，我们将研究通过缩小每个元件并将其集成到单个设备中来实现光谱仪，传感器和机械平移台深度分析的策略。再加上关于降低功耗以允许从汽车电池操作的额外研究，包括用于NMR设备与物体精确平行对准的传感器，以及显着提高设置的坚固性，e. G.通过提高其对电磁干扰的耐受性，将研究和原型化一种研究仪器，使杂散场NMR的全新现场应用成为可能。这包括在线生产线上的无损材料检测，以及博物馆、遗产和户外挖掘现场的应用。一个由三名PI组成的跨学科小组将确保设想的原型与现场和实地要求的兼容性，并在实验室测试和试点研究中对其进行验证。

Stray-field NMR is a technique for nondestructive materials testing in the laboratory. It is well established in the scientific community and industry. Primary applications are found in quality control and aging of polymers and related materials, including PE pipes, PVC flooring, car tires, asphalt pavements, human skin, and food products. These materials can, in many cases, be serviced with commercial laboratory-based technology from vendors such as Magritek and Bruker. However, the dead time of the current sensors is too long for useful materials analysis applied to e. g. bound water in building materials such as cement, glass- and carbon-fiber-reinforced polymer composites in windmill wings, and varnish on paintings and musical instruments. Moreover, emerging applications such as the analysis of tangible cultural heritage and outdoor measurements would greatly benefit from improvements concerning the equipment to function in remote locations and under adverse environmental conditions and the identification of relevant correlations between NMR relaxation/diffusion and application parameters. The main scientific goal of this project is to achieve a significant reduction of the dead time of compact stray-field NMR sensors from currently 70 µs to less than 20 µs at 10 mm depth of access. Moreover, we will investigate strategies for miniaturizing the spectrometer, sensor, and mechanical translation stage for depth profiling by shrinking each element and integrating them into a single device. Together with additional research on reducing the power consumption to allow for operation from a car battery, on including a sensor for the precise parallel alignment of the NMR device with the object, and significantly improving the ruggedness of the setup, e. g. by increasing its tolerance to electromagnetic interference, a research instrument will be investigated and prototyped that enables entirely new in-field applications of stray-field NMR. This includes nondestructive materials testing at production lines online, as well as applications in museums, heritage, and excavation sites outdoors. An interdisciplinary team of three PIs will ensure compatibility of the envisioned prototype with in situ and in-field requirements and validate it in laboratory tests and pilot studies.