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International Journal on Smart Sensing and Intelligent Systems

Professor Subhas Chandra Mukhopadhyay

Exeley Inc. (New York)

Subject: Computational Science & Engineering, Engineering, Electrical & Electronic


eISSN: 1178-5608



VOLUME 7 , ISSUE 4 (December 2014) > List of articles


Hung Dang Phuc * / Patrick Poulichet * / Tien Truong Cong / Abdennasser Fakri / Christophe Delabie / Latifa Fakri-Bouchet *

Keywords : Nuclear Magnetic Resonance (NMR); Low field; Portable Permanent Magnet; Halbach; Shim magnets; Homogeneity, Simulation, Finite Element Method (FEM).

Citation Information : International Journal on Smart Sensing and Intelligent Systems. Volume 7, Issue 4, Pages 1,555-1,578, DOI:

License : (CC BY-NC-ND 4.0)

Received Date : 27-September-2014 / Accepted: 05-November-2014 / Published Online: 01-December-2014



A light weight, simple design NMR apparatus consists of 24 identical magnets arranged in Halbach array was designed and built. The homogeneity of the magnetic field B0 can be improved by dividing a long magnets into several rings. The size of the useful volume depends on both the gap between each ring and some others shim magnets. Our aim is to enhance the sensitive volume and to maintain the highest magnetic static field (B0). This apparatus generates a B0 field strength of about 0.1 T. This work focuses on the magneto-static simulation of NdFeB magnets arrangement and on the comparison with the measurement of the magnetic field strength and homogeneity in three dimensions (3D). The homogeneity of the magnetic field B0 is optimized with the help of CAD and mathematical software. Our results were also validated with a Finite Element Method (FEM). The simulation results of the strength and of the homogeneity of B0 field were compared to those obtained with a digital gaussmeter. The homogeneity in the magnet longitudinal axis and the field B0 strength are similar. However, the homogeneity in transverse plane differs from simulation and measurement because of the quality of the magnets. In order to improve the homogeneity, we propose a new shim method.

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[1] S. Anferova, V. Anferov, M. Adams, P. Blümler, N. Routley, K. Hailu, K. Kupferschläger, M. j. d. Mallett, G. Schroeder, S. Sharma, and B. Blümich, “Construction of a NMR-MOUSE with short dead time,” Concepts Magn. Reson., vol. 15, no. 1, pp. 15–25, Mar. 2002.
[2] G. Moresi and R. Magin, “Miniature permanent magnet for table-top NMR,” Concepts Magn. Reson., vol. 19B, no. 1, pp. 35–43, 2003.
[3] G. Navon, U. Eliav, D. E. Demco, and B. Blümich, “Study of order and dynamic processes in tendon by NMR and MRI,” J. Magn. Reson. Imaging, vol. 25, no. 2, pp. 362–380, Feb. 2007.
[4] F. J. Rühli, T. Böni, J. Perlo, F. Casanova, M. Baias, E. Egarter, and B. Blümich, “Non-invasive spatial tissue discrimination in ancient mummies and bones in situ by portable nuclear magnetic resonance,” J. Cult. Herit., vol. 8, no. 3, pp. 257–263, Jul. 2007.
[5] B. Blümich, F. Casanova, J. Perlo, S. Anferova, V. Anferov, K. Kremer, N. Goga, K. Kupferschläger, and M. Adams, “Advances of unilateral mobile NMR in nondestructive materials testing,” Magn. Reson. Imaging, vol. 23, no. 2, pp. 197–201, Feb. 2005.
[6] T. Poli, L. Toniolo, M. Valentini, G. Bizzaro, R. Melzi, F. Tedoldi, and G. Cannazza, “A portable NMR device for the evaluation of water presence in building materials,” J. Cult. Herit., vol. 8, no. 2, pp. 134–140, Apr. 2007.
[7] H. Pedersen, S. Ablett, D. Martin, M. J. Mallett, and S. Engelsen, “Application of the NMR-MOUSE to food emulsions,” J. Magn. Reson., vol. 165, no. 1, pp. 49–58, Nov. 2003.
[8] B. Blümich, V. Anferov, S. Anferova, M. Klein, R. Fechete, M. Adams, and F. Casanova, “Simple NMR-mouse with a bar magnet,” Concepts Magn. Reson., vol. 15, no. 4, pp. 255–261, Dec. 2002.
[9] W.-H. Chang, J.-H. Chen, and L.-P. Hwang, “Single-sided mobile NMR with a Halbach magnet,” Magn. Reson. Imaging, vol. 24, no. 8, pp. 1095–1102, Oct. 2006.
[10] C. W. Windt, H. Soltner, D. van Dusschoten, and P. Blümler, “A portable Halbach magnet that can be opened and closed without force: The NMR-CUFF,” J. Magn. Reson., vol. 208, no. 1, pp. 27–33, Jan. 2011.
[11] X. Zhang, V. Mahesh, D. Ng, R. Hubbard, A. Ailiani, B. O’Hare, A. Benesi, and A. Webb, “Design, construction and NMR testing of a 1 tesla Halbach Permanent Magnet for Magnetic Resonance,” in COMSOL Users Conference, Boston, 2005.
[12] K. Halbach, “Design of permanent multipole magnets with oriented rare earth cobalt material,” Nucl. Instrum. Methods, vol. 169, no. 1, pp. 1–10, Feb. 1980.
[13] H. Raich and P. Blümler, “Design and construction of a dipolar Halbach array with a homogeneous field from identical bar magnets: NMR Mandhalas,” Concepts Magn. Reson. Part B Magn. Reson. Eng., vol. 23B, no. 1, pp. 16–25, Oct. 2004.
[14] H. Soltner and P. Blümler, “Dipolar Halbach magnet stacks made from identically shaped permanent magnets for magnetic resonance,” Concepts Magn. Reson. Part A, vol. 36A, no. 4, pp. 211–222, Jul. 2010.
[15] B. P. Hills, K. M. Wright, and D. G. Gillies, “A low-field, low-cost Halbach magnet array for open-access NMR,” J. Magn. Reson., vol. 175, no. 2, pp. 336–339, Aug. 2005.
[16] E. Danieli, J. Mauler, J. Perlo, B. Blümich, and F. Casanova, “Mobile sensor for high resolution NMR spectroscopy and imaging,” J. Magn. Reson., vol. 198, no. 1, pp. 80–87, May 2009.
[17] C. Hugon, F. D’Amico, G. Aubert, and D. Sakellariou, “Design of arbitrarily homogeneous permanent magnet systems for NMR and MRI: Theory and experimental developments of a simple portable magnet,” J. Magn. Reson., vol. 205, no. 1, pp. 75–85, Jul. 2010.
[18] R. C. Jachmann, D. R. Trease, L.-S. Bouchard, D. Sakellariou, R. W. Martin, R. D. Schlueter, T. F. Budinger, and A. Pines, “Multipole shimming of permanent magnets using harmonic corrector rings,” Rev. Sci. Instrum., vol. 78, no. 3, p. 035115, Mar. 2007.
[19] "Radia Introduction." [Online]. [Accessed: 05-Oct-2014].
[20] “ANSYS - Simulation Driven Product Development.” [Online]. Available: [Accessed: 13-Aug-2014].
[21] “HKCM MAGNETS from STOCK, from FACTORY & MAGNETS ON DEMAND.” [Online]. Available: [Accessed: 11-Jul-2014].
[22] P. Poulichet, Hung Dang Phuc, Tien Truong Cong, Latifa Fakri-Bouchet, Abdennasser Fakri, and Christophe Delabie, “Simulation and optimisation of homogeneous permanent magnet for portable NMR applications,” 8th International Conference on Sensing Technology, Liverpool, UK., 04-Sep-2014.