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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Difracción de RMN y estadísticas espaciales de sistemas estacionarios
Science (New York, N.Y.)
|February 7, 1992
Resumen
Las imágenes espaciales de resonancia magnética nuclear (RMN) ofrecen un método rápido para analizar las variaciones de densidad de los materiales. Esta técnica proporciona información sobre la granularidad y porosidad sin necesidad de datos de movilidad o tiempo de transporte.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física Física es la física de las cosas.
- Química Química es la química.
Sus antecedentes:
- Las imágenes espaciales de resonancia magnética nuclear (RMN) pueden proporcionar datos análogos a los experimentos de difracción.
- Las escalas de longitud en RMN están determinadas por las intensidades del gradiente, no por las longitudes de onda de la radiación.
- Este método accede a las autocorrelaciones de densidad de muestra para caracterizar variaciones a pequeña escala.
Objetivo del estudio:
- Explorar imágenes espaciales de RMN para la caracterización rápida de la morfología de muestras masivas.
- Para investigar la RMN "funciones de Patterson" para el análisis de granularidad y porosidad.
Principales métodos:
- Adquisición, procesamiento e interpretación de datos de imágenes espaciales de RMN.
- Utilizando las fuerzas del gradiente para definir escalas de longitud.
- La generación de RMN "funciones de Patterson".
Principales resultados:
- Las "funciones de Patterson" de RMN se pueden adquirir órdenes de magnitud más rápido que las imágenes de RMN comparables.
- Este enfoque permite la caracterización espacial de pequeñas características en materiales a granel.
- La granularidad y la porosidad se pueden examinar sin necesidad de movilidad, penetrantes o tiempo de transporte.
Conclusiones:
- Las imágenes espaciales de RMN ofrecen un método rápido y eficaz para la caracterización de materiales.
- El enfoque de la RMN "función de Patterson" es adecuado para analizar la morfología de los materiales estructurales.
- Esta técnica proporciona una valiosa alternativa a los métodos basados en la difusión para evaluar las propiedades de los materiales.
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