Fig. 7: Evolution of the polarization of the fixed proton of the target \(\left(\right.({{\boldsymbol{P}}}({{{\boldsymbol{S}}}}_{{{\boldsymbol{Z}}}}^{4}))\) and the 13C of the target \(\left(\right.({{\boldsymbol{P}}}({{{\boldsymbol{S}}}}_{{{\boldsymbol{Z}}}}^{3}))\) for different longitudinal relaxation times \({{{\boldsymbol{T}}}}_{1}^{{{\boldsymbol{L}}}}\) of the labile protons.
From: Nuclear spin polarization of lactic acid via exchange of parahydrogen-polarized protons

There is a monotonous increase of the 1H (a) and 13C (b) target polarization with increasing \({T}_{1}^{L}\). Note that MFC is applied at 2400 ms and the dashed lines indicate the transitions between the magnetic fields. Here, BPol0 = 90 mT and BPol1 = 50 µT were used.