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Buried landmines are difficult to find, especially if they contain no metal parts. Now researchers at the Technical University of Darmstadt in Germany say a technique for looking inside the human body could help (Journal of Physics D, vol 35, p 939). In nuclear magnetic resonance, molecules placed in a powerful magnetic field emit a characteristic pattern of radio waves. With the operator at a safe distance, an NMR-based landmine detector could determine the substance’s chemical make-up and its position in the ground from the pattern of waves. The team says the technique could be particularly useful for identifying TNT,…