The NMR in solid state is characterized by the following drawbacks:Dipolar coupling between nucleidepends on the interaction between the dipolar moment of vicinal nucleithrough the intra- and inter-molecular spaceinliquidstatethemoleculartumblingaveragetheseinteractionsand cancel out the total dipolar couplingSignal amplitude < 1Hzin solid state the strong dipolar coupling between H nuclei do notallow the 1H-NMR experimentSolid state 13C NMR experimentin solid state the dipolar coupling between H and C decrease theresolution and increase the signal amplitude over 100 HzIREEA-NanjingAgriculturalUniversity/April2008
The NMR in solid state is characterized by the following drawbacks: Dipolar coupling between nuclei depends on the interaction between the dipolar moment of vicinal nuclei through the intra- and inter-molecular space in liquid state the molecular tumbling average these interactions and cancel out the total dipolar coupling Signal amplitude < 1Hz in solid state the dipolar coupling between H and C decrease the resolution and increase the signal amplitude over 100 Hz in solid state the strong dipolar coupling between H nuclei do not allow the 1H-NMR experiment Solid state 13C NMR experiment IREEA-Nanjing Agricultural University/ April 2008
The solid state drawbacks are removed or reduced :application of high power dipolar decoupling techniqueremove the dipolar coupling between H and C nucleithe sample is positioned at 54° respect to Bo (Magic Anglespinning the sample at higher angular velocity5KHz<->15KHzBOwith MagicAngle Spinning (MAS)solid state resemble to liquid stateMAS reduce the CSAeffectIREEA-NanjingAgriculturalUniversity/April2008
The solid state drawbacks are removed or reduced : • spinning the sample at higher angular velocity 5KHz < ÷ >15KHz • the sample is positioned at 54° respect to Bo (Magic Angle) with MagicAngle Spinning (MAS) solid state resemble to liquid state MAS reduce the CSA effect • application of high power dipolar decoupling technique remove the dipolar coupling between H and C nuclei B0 IREEA-Nanjing Agricultural University/ April 2008
IREEA-Nanjing AgriculturalUniversity/April20081:011:J~+~+~CC3, C4C1, C6HzC10FerulicC2, C59 CC7C85solid state (MAS)C1, C610C9C10resolution > 30Hz5C502C3, C4OCH34C8C7OH755025150125100175ppm
ppm 175 150 125 100 75 50 25 ppm C9 C10 C3, C4 C2, C5 C7 C1, C6 C8 solid state (MAS) 10 resolution > 30Hz COOH OH 1 2 3 4 5 6 7 8 9 OCH3 Ferulic acid liquid state resolution < 1Hz IREEA-Nanjing Agricultural University/ April 2008 C10 C9 C3, C4 C2, C5 C7 C1, C6 C8
IREEA-NanjingAgriculturalUniversity/April2008Molecular characterization of soil humic acidafter recycled organic biomass additionDr.SpacciniRiccardo
Dr. Spaccini Riccardo Molecular characterization of soil humic acid after recycled organic biomass addition IREEA-Nanjing Agricultural University/ April 2008
IREEA-Nanjing AgriculturalUniversity/April2008OBJECTIVEMolecular characterization of soil humic acids extracted after soiltreatments with recycled organic biomassbulk characterizationSpectroscopic analyses:CPMAS13CNMR (CrossPolarizationMagicAngleSpinning)molecularcharacterization Seguential extractionsGasCromatografyMassSpectrometry
Molecular characterization of soil humic acids extracted after soil treatments with recycled organic biomass • IR-DRIFT (Diffuse Reflectance Infrared Fourier Transform) GasCromatografy MassSpectrometry • Sequential extractions • CPMAS13CNMR (CrossPolarizationMagicAngleSpinning) Spectroscopic analyses: off-line pyrolysis with TetraMethylAmmoniumHydroxide (TMAH termochemolysis) bulk characterization molecular characterization OBJECTIVE IREEA-Nanjing Agricultural University/ April 2008