Montagem de um sistema básico para detecção de um sinal de ressonância magnética nuclear

Abstract

NMR techniques have a wide application in several branches of science, in which it is necessary to determine concentrations of nuclear spins. They are used in the identification of compound substances as in organic chemistry, in the control of synthesis products, in the demonstration of the composition and structure of products and in the quantitative analysis of mixtures of organic liquids etc. These techniques are very effective in the analysis of liquid mixtures, in the determination of absolute humidity and in the concentration of water in industrial products such as oils, preserves, cigarettes, and even in oils and fuels. In biological tissues and in medicine, both human and veterinary, the applicability of these techniques gains greater relevance due to the great information provided by the measured parameters, the ability to make them correspond to a well-located group of molecules and the great sensitivity of the method in very weak chemical interactions. As introscopy is the ability to visualize the distribution of NMR parameters by the sample that the method provides, it is natural that it should be called for use in the aforementioned cases. The present work presents the construction of the spin echo spectrometer, as well as the application of NMR techniques in the various branches of science and the advantages they have in relation to others existing in spectroscopy, due to their fast, non-destructive and non-invasive. Much of the material used to build the spectrometer was imported while the other, although not a national product, was acquired in Brazil. This fact may have been the basic premise for the difficulties faced during the performance of the work, since some elements did not correspond to expectations, as the observed signal had noise. Causes and possible necessary solutions have been identified. The importance of this work is not only limited to the construction of the device and subsequent observation of the signal, but, above all, in calling attention to government entities and to the national business community for the great importance that the use of these techniques could bring to the country.(TRADUÇÃO NOSSA)