Nuclear magnetic resonance drawing

At first sight, instrumentation, even physical instrumentation within organic chemistry, may not appear to be an interdisciplinary area. However, if by interdisciplinary we mean an intellectual zone where scientists from different disciplines meet and interact, no field could be more deserving of the title. Not only did the construction of these instruments draw on new developments in electronics and optics and stimulated further innovation, but the techniques themselves came from outside organic chemistry. Nuclear magnetic resonance and mass spectroscopy, to give just two pertinent examples, crossed over from physics, and organic chemists had to collaborate with chemical physicists to obtain the best results from these new techniques. 

To draw conclusions concerning the templating effect of different molecules, comparable conditions for the crystallization process must be used. In this paper we present a systematic investigation on the effect of mono-, di- and tri-n-alkylamine and tetraalkylammonium compounds (alkyl = C. - C,) upon the rate of crystallization, yield and the properties of the products. Also the field of a template-free synthesis is studied. The products were characterized by magic-angle-spinning nuclear magnetic resonance spectroscopy (MAS NMR) and X-ray diffraction. 

It is closely related to the analytically more important technique of nuclear magnetic resonance (NMR) and we draw comparisons widely herein, since NMR will be much more widely understood by our readers. 

Schematic drawing of a nuclear magnetic resonance spectrometer.

Nuclear magnetic resonance is a physical phenomenon that lies at the heart of both NMR spectroscopy and MRI. However, these two technologies differ in their applications, and while NMR spectroscopy is widely adopted for identification and characterization of biomolecules, MRI is used for non-invasive visualization (imaging) of the inside of living organisms. In order to understand these technologies it is important to consider their historical development and draw comparisons with other related techniques. 

I single out only one technique this section is concluded by drawing attention to the recent application of deuterium nuclear magnetic resonance (NMR) to the characterization of the spacer component... 

It has been observed that the expansivity of amorphous polymers is drastically affected by orientation. increases by 10-30% with increasing draw ratio while a exhibits a larger decrease [32]. The thermal expansion behavior of amorphous polymers is reasonably described by the aggregate model [71-73] using the orientation function determined by nuclear magnetic resonance measurements [74, 75]. According to... 

No attempt will be made here to review and correlate the large number of ultraviolet, infrared, nuclear magnetic resonance, and mass spectra that have been recorded, interpreted, and used in structure determination of pyridinols and pyridones. Articles that contain significant spectral data and/or discussions are noted in the Tables. The role of spectroscopic techniques, ionization constants, and dipole moments in the studies of structure and tautomerism of heterocyclic compounds has been reviewed recently by Albert. Although ionization constants have been used to estimate pyridinol-pyridpne equilibrium constants with some success, caution must be exercised about drawing conclusions from this type of data. ... 

Our investigations of this system center on four aspects. First, to establish that the compatible mixtures indeed represent the thermodynamically stable states at room temperature second, to find the upper phase boundary of the mixtures third, to explore the use of nuclear magnetic resonance to study molecular motion which allows us to draw conclusions about the scale of homogeneity of mixing and fourth, to study the morphology and kinetics of phase separation, in particular, spinodal decomposition associated with LCST. 

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