The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 28, 1978
Filed:
Dec. 29, 1976
Donald C Hofer, Poughkeepsie, NY (US);
Vincent N Kahwaty, Poughkeepsie, NY (US);
Carl R Valentino, Hopewell Junction, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method is described for the quantitative analysis of a solution in which the solvent produces a nuclear magnetic resonant (NMR) spectral peak that dominates the system. A first spectrum containing the peak is made by operation of a nuclear magnetic resonant spectrometer at a first gain setting. The NMR apparatus is a pulse-modulated, Fourier-transform type spectrometer. A second spectrum is produced in which a 180.degree. pulse is applied to invert the spectral component magnetization followed after a period of time by a 90.degree. pulse. The period of time is sufficient to allow the solvent or component producing the unwanted peak to relax from the inverted state to a point where there is minimum magnetization along the longitudinal axis. At this point, in many solutions the other components have completely relaxed so that the 90.degree. pulse produces a free induction decay signal which, after undergoing the Fourier-transformation, yields a spectrum that does not include any significant peak due to the solvent. Thereafter, the quantitative analysis is performed by measuring the areas under the respective component peaks and simultaneously solving a series of equations in which the weight of the various components is proportional to the respective areas under the peaks and to the gain settings of the spectrometer.