Nuclear magnetic resonance thermal properties

Effect of nonaqueous solvents on acid-base properties of NGu) (Acidic in dimethyl-formamide, pyridine and acet basic in HAc and formic acid) 26) E. Ripper, Explosivst 17 (7), 145-51 (1969) Bt CA 72, 48454(1970) (a-and /3-Nitroguanidine) (Reinvestigation of both forms by IR UV, Nuclear Magnetic Resonance (NMR), Differential Thermal Analysis (DTA),... 

Solid-state nuclear magnetic resonance (NMR) has been extensively used to assess structural properties, electronic parameters and diffusion behavior of the hydride phases of numerous metals and alloys using mostly transient NMR techniques or low-resolution spectroscopy [3]. The NMR relaxation times are extremely useful to assess various diffusion processes over very wide ranges of hydrogen mobility in crystalline and amorphous phases [3]. In addition, several borohydrides [4-6] and alanates [7-11] have also been characterized by these conventional solid-state NMR methods over the years where most attention was on rotation dynamics of the BHT, A1H4, and AlHe anions detection of order-disorder phase transitions or thermal decomposition. There has been little indication of fast long-range diffusion behavior in any complex hydride studied by NMR to date [4-11]. 

The results of the characterization of cured phthalonitrile resins are presented. This includes their thermal properties from thermal gravimetric analysis and differential scanning calorimetry, spectroscopic properties from the infra-red and nuclear magnetic resonance techniques, and mechanical properties from torsional pendulum analysis and fracture mechanics evaluation. 

In contrast to previous explosive periods, we have every expectation that research by both physicists and chemists on liquid crystals will continue to accelerate for the foreseeable future for several salient reasons. The first is the variety and importance of systems in which liquid crystals are observed—in biological systems and in items of commerce such as detergents and polymers. The second is the new instrumental techniques to evaluate the intermolecular forces which determine the properties of the unique liquid crystalline state. These techniques include differential thermal analysis and nuclear magnetic resonance. We are now in the eye of this activity and have the happy prospect of a stimulating future in a continuing growth period for studying both ordered fluids and liquid crystals. 

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