Ancient architectures such as the Great Wall are symbols and pride of the Chinese nation, and precious treasures of the world. Portable NMR detection devices have been proposed to examine the building materials of such ancient architectures non-invasively, and to provide information regarding the science, technology and engineering behind these architectures. In this study, the magnets for such portable NMR detection devices were designed and built, which were all based on a semi-Halbach magnet structure. On top of the basic design, different modules were added to achieve different functionality, including the magnet for mobile measurement, the magnet for high depth measurement, and the "homogeneous" field mode. The measured magnetic field (B0) distributions for these magnets agreed well with the simulated results, with only slight differences. Experiments on bricks were performed to verify the performance of these magnets.
TANG Lian
,
CHEN Wei-liang
,
ZHAO Kun
,
SUN Zhe
,
ZHOU Hua
,
WANG Jie
,
ZHANG Yan
,
LIU Hua-bing
,
XIANG Wen-feng
,
XIAO Li-zhi
,
LIAO Guang-zhi
. Design of Magnets for in Situ NMR Detection Devices Intended for Preservation of Ancient Architectures[J]. Chinese Journal of Magnetic Resonance, 2017
, 34(3)
: 372
-382
.
DOI: 10.11938/cjmr20172569
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