@article{8cf3fb7ef2c54fb38ee28370418add7b,
title = "A compact permanent magnet for microflow NMR relaxometry",
abstract = "We design and demonstrate a compact, robust, and simple to assemble and tune permanent magnet suitable for NMR relaxometry measurements of microfluidic flows. Soft-magnetic stainless-steel plates, incorporated inside the magnet airgap, are key for obtaining substantially improved and tunable field homogeneity. The design is scalable for different NMR probe sizes with the region of suitable field homogeneity, less than 200 ppm, achievable in a capillary length of about 50 % of the total magnet length. The built physical prototype, having 3.5x3.5x8.0 cm3 in size and 5 mm high airgap, provides a field strength of 0.5 T and sufficient field homogeneity for NMR relaxometry measurements in capillaries up to 1.6 mm i.d. and 20 mm long. The magnet was used for test flow rate measurements in a wide range, from 0.001 ml/min to 20 ml/min.",
keywords = "UT-Hybrid-D, low-field NMR, Microflow, NMR-on-a-chip, Permanent magnet, Relaxometry, Flow measurements",
author = "Dmytro Polishchuk and Han Gardeniers",
note = "Funding Information: This work is (partly) funded by the Dutch Research Council (NWO) through the research programme FLOW+, project number 15025. The authors thank Jankees Hogendoorn, Lucas Cerioni, Marco Zoeteweij, and Koert Kriger of Krohne New Technologies BV, Eren Aydin of Delft University of Technology, and Rob Dierink of the technical center (TCO) at the University of Twente for their input and support. Funding Information: This work is (partly) funded by the Dutch Research Council (NWO) through the research programme FLOW+, project number 15025. The authors thank Jankees Hogendoorn, Lucas Cerioni, Marco Zoeteweij, and Koert Kriger of Krohne New Technologies BV, Eren Aydin of Delft University of Technology, and Rob Dierink of the technical center (TCO) at the University of Twente for their input and support. Publisher Copyright: {\textcopyright} 2022 The Author(s)",
year = "2023",
month = feb,
doi = "10.1016/j.jmr.2022.107364",
language = "English",
volume = "347",
journal = "Journal of magnetic resonance",
issn = "1090-7807",
publisher = "Elsevier",
}