Sample preparation solid-state nuclear magnetic resonance

Raman spectroscopy with variable temperature accessories has been valuable for probing phase transitions within solid-state pharmaceutical samples. In combination with other techniques [x-ray diffractometry, solid-state nuclear magnetic resonance (NMR), FTIR spectroscopy, and thermal analysis], the molecular basis for thermal transitions between dihydrates of carbamazepine prepared from different polymorphs of the drug were re-... 

Interest in the structures and properties of fullerenes has received new impetus from the recent discovery that the molecules Cm and C70 can be prepared in large quantities by comparatively simple procedures. The ready availability of solid samples of Cm and C70 now permits their characterization by a variety of physical methods. In this paper, we report the results of solid-state C nuclear magnetic resonance (NMR) measurements on powder samples of Cm and of a mixture of Cm and C70. Our NMR results indicate that Cm rotates rapidly and nearly isotropically in the solid state at 296 K and that C70 also rotates at 296 K, although somewhat anisotropically. The rotation of Cm molecules becomes slow on the time scale of our measurements at about 100 K. 

Exploring various phenomena at metal/solution interfaces relates directly to heterogeneous catalysis and its applications to fuel cell catalysis. By the late 1980s, electrochemical nuclear magnetic resonance spectroscopy (EC-NMR) was introduced as a new technique for electrochemical smface science. (See also recent reviews and some representative references covering NMR efforts in gas phase surface science. ) It has been demonstrated that electrochemical nuclear magnetic resonance (EC-NMR) is a local surface and bulk nanoparticle probe that combines solid-state, or frequently metal NMR with electrochemistry. Experiments can be performed either under direct in situ potentiostatic control, or with samples prepared in a separate electrochemical cell, where the potential is both known and constant. Among several virtues, EC-NMR provides an electron-density level description of electrochemical interfaces based on the Eermi level local densities of states (Ef-LDOS). Work to date has been predominantly conducted with C and PtNMR, since these nuclei... 

To determine the polymer(s) that are present in a rubber it is usual to use either Fourier-transform infrared spectroscopy or nuclear magnetic resonance (NMR) spectroscopy. These techniques are normally applied to a sample that has undergone some preliminary preparation. For example, a solvent extraction can be carried out to remove process oils and other low-Mw organic compounds and then the extracted sample is often pyrolysed to remove any interferences from the fillers present. As solid-state NMR techniques become more advanced and sensitive, however, it may become easier to obtain this information directly on samples in the future. 

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