Low-field Time-Domain Nuclear Magnetic Resonance (TD-NMR) has become an important experimental approach for a wide variety of applications. While its early use was largely restricted to relaxation measurements, continuous developments in instrumentation and methodology have substantially extended its capabilities. As a result, TD-NMR is now widely employed for the characterization of material properties, particularly in systems with complex microstructures such as porous media. In ¹H TD-NMR studies of solid and soft materials, through-space magnetic dipolar couplings between ¹H nuclear spins play a crucial role, rendering the NMR signals highly sensitive to molecular packing and molecular mobility. This intrinsic sensitivity makes ¹H TD-NMR especially effective for identifying mobility transitions, including segmental motions in soft materials, freezing and melting phase transitions, and the dissolution of solids. In this presentation, we focus on the application of a method based on dipolar filtering combined with the Magic Sandwich Echo (MSE) sequence, originally developed for the investigation of soft materials, to probe the properties of porous media. These applications include the characterization of mesoporous structures by NMR cryoporometry and the study of fertilizer dissolution processes in soils. 
Acknowledgements: CNPq (Grant number 308760/2022-0)