Journal of Magnetics

  • 제19권2호
  • /
  • Pages.155-160
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  • 2014
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  • 1226-1750(pISSN)
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  • 2233-6656(eISSN)
한국자기학회 (The Korean Magnetics Society)
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Power Absorption Measurements during NMR Experiments

  • Felix-Gonzalez, N. (Centre for Biomedical Technology, Technical University of Madrid) ;
  • Urbano-Bojorge, A.L. (Centre for Biomedical Technology, Technical University of Madrid) ;
  • de Pablo, C. Sanchez-L (Centre for Biomedical Technology, Technical University of Madrid) ;
  • Ferro-Llanos, V. (Centre for Biomedical Technology, Technical University of Madrid) ;
  • del Pozo-Guerrero, F. (Centre for Biomedical Technology, Technical University of Madrid) ;
  • Serrano-Olmedo, J.J. (Centre for Biomedical Technology, Technical University of Madrid)
  • 투고 : 2013.07.01
  • 심사 : 2013.12.20
  • 발행 : 2014.06.30
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초록

The heating produced by the absorption of radiofrequency (RF) has been considered a secondary undesirable effect during MRI procedures. In this work, we have measured the power absorbed by distilled water, glycerol and egg-albumin during NMR and non-NMR experiments. The samples are dielectric and examples of different biological materials. The samples were irradiated using the same RF pulse sequence, whilst the magnetic field strength was the variable to be changed in the experiments. The measurements show a smooth increase of the thermal power as the magnetic field grows due to the magnetoresistive effect in the copper antenna, a coil around the probe, which is directly heating the sample. However, in the cases when the magnetic field was the adequate for the NMR to take place, some anomalies in the expected thermal powers were observed: the thermal power was higher in the cases of water and glycerol, and lower in the case of albumin. An ANOVA test demonstrated that the observed differences between the measured power and the expected power are significant.

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참고문헌

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