Fig. 3. Polarization P(1H) measured using microwave frequency modulation at 4.2 K (top) and 1.2 K (bottom) and 6.7 T as a function of radical concentration (in μmolNO cm–3) for: HYPSO-2 (
) and HYPSO-3 (
) impregnated with D2O : H2O (8 : 2). The open circles 
and triangles 
correspond to a solution of 40 mM TEMPOL in H2O : D2O : glycerol-d8 (10 : 40 : 50) impregnated in 1/140_N3_SBA-16 (radical-free HYPSO-3) and 1/140_N3_SBA-15 (radical-free HYPSO-2), respectively. The grey square 
corresponds to a TEMPOL reference DNP solution, without HYPSO.
