Construção de uma sonda \textit{microslot} para Ressonância Magnética Nuclear
     Construction of a microslot probe for Nuclear Magnetic Resonance

Luís Guilherme Uhlig, Alexandre M. Souza

Resumo


Os experimentos de ressonância magnética Nuclear (RMN) possuem baixa sensibilidade, o que limita a utilização da técnica. Uma das abordagens para aumentar a sensibilidade do experimento é a miniaturização do circuito ressonador contido na sonda, com o desenvolvimento de microrressonadores. Este trabalho apresenta a construção de um circuito para uma sonda do tipo \textit{microslot} mediante o emprego da técnica de litografia com \textit{LASER}. Foram realizados experimentos para comparar o desempenho do \textit{microslot} com duas outras sondas comerciais do tipo sela. A sonda do tipo \textit{microslot} apresentou maior fator de eficiência, pois esta pode gerar um campo magnético mais intenso para uma dada potência elétrica. Também é mostrado que a resolução obtida com a sonda \textit{microslot} permite a observação de grupos químicos diferentes.

Palavras chave:  Microrressonador, \textit{microslot}, ressonância nuclear magnética.

Nuclear magnetic resonance experiments (NMR) have low sensitivity, which limits the usage of the technique. One approach to enhance the sensitivity of NMR experiments is the miniaturization of the resonant circuit contained in the probe, by developing microcoils or microresonators. This work presents the construction of a microslot probe using LASER lithography. Experiments were performed to compare the microslot probe and commercial saddle type probes. The microslot probe presented higher efficiency factor, since it can generate a more intense magnetic field for a given electrical power. We also show that the resolution obtained with the microslot probe allows the observation of different chemical groups.

Keywords: Microresonator, microslot, nuclear magnetic resonance.


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DOI: http://dx.doi.org/10.7437/nt-cbpf.v7i1.246