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OP-I-28dimensional profiles detected along the catalyst bed demonstrated temperaturevariations along the bed axis. More recently, these studies were extended toward theobservation of dynamic heat transfer processes in individual catalyst particles andthe two-dimensional temperature mapping of the catalyst bed. Hydrogenation ofunsaturated compounds and the oxidation of H 2 were used for these initial modelstudies. It is expected that MRI could become a useful tool for the characterization ofheat transport in operating catalytic reactors and for the visualization of hot spotsformation and evolution.Applications of the MRI toolkit are often limited by a relatively low sensitivity of thetechnique. For instance, MRI studies of hydrodynamics in micoreactors are difficultusing conventional approaches. Hydrogenation reactions can be employed todevelop hypersensitive MRI schemes. When parahydrogen is used in hydrogenationof unsaturated substrates, the products can exhibit an enhancement of their NMRsignals by several orders of magnitude provided that the reaction mechanismensures a pairwise addition of the two H atoms of the para-H 2 molecule to the samesubstrate. We have demonstrated recently that both immobilized metal complexesand supported metal catalysts are capable of producing significant signalenhancements when used in heterogeneous hydrogenation processes [4,5]. Thesignal enhancement levels achieved so far are about two orders of magnitude shortof the possible limiting value, and catalysts more suitable for such applications arestill to be identified. Nevertheless, we demonstrate that the signal enhancementalready achieved allows one to successfully apply MRI to study various masstransport processes [6] including hydrodynamics in microfluidic chips.References[1] A.A. Lysova, I.V. Koptyug, A.V. Kulikov, V.A. Kirillov, R.Z. Sagdeev, Topics Catal., 2009, 52,1371.[2] A.A. Lysova, I.V. Koptyug, A.V. Kulikov, V.A. Kirillov, R.Z. Sagdeev, V.N. Parmon, Chem. EngngJ., 2007, 130, 101.[3] I.V. Koptyug, A.V. Khomichev, A.A. Lysova, R.Z. Sagdeev, J. Am. Chem. Soc., 2008, 130, 10452.[4] I.V. Koptyug, K.V. Kovtunov, S.R. Burt, M.S. Anwar, C. Hilty, S. Han, A. Pines, R.Z. Sagdeev, J.Am.. Chem. Soc., 2007, 129, 5580.[5] K.V. Kovtunov, I.E. Beck, V.I. Bukhtiyarov, I.V. Koptyug, Angew. Chem. Int. Ed., 2008, 47, 1492.[6] L.-S. Bouchard, S.R. Burt, M.S. Anwar, K.V. Kovtunov, I.V. Koptyug, A. Pines, Science, 2008,319, 442-445.AcknowledgmentsThis work was partially supported by the grants from RAS (5.1.1), RFBR (08-03-00661,08-03-00539), SB RAS (67, 88), the program of support of leading scientific schools(NSh-7643.2010.3), FASI (state contract 02.740.11.0262) and CRDF (RUC1-2915-NO07).A.A. Lysova thanks SB RAS for the award of the Lavrentiev grant for young scientists.91