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Los fullerenos en la capa límite cretáceo-terciario
Science (New York, N.Y.)
|July 29, 1994
Resumen
Se encontraron fullerenos (C60) en muestras de hollín del límite Cretácico-Terciario (K-T). Esto sugiere que los incendios forestales, no solo los impactos de asteroides, pueden haber producido estas moléculas en el evento K-T.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- Paleontología Paleontología.
- Química orgánica es la química orgánica.
Sus antecedentes:
- El límite Cretácico-Terciario (K-T) marca un evento de extinción masiva.
- Los fullerenos, incluido el C60, son moléculas complejas de carbono.
- Se debate el origen de los fullerenos extraterrestres o terrestres en el límite K-T.
Objetivo del estudio:
- Para analizar el hollín límite K-T para el contenido de fullereno.
- Para comparar las concentraciones de fullereno con las de la combustión terrestre.
- Para investigar los posibles orígenes de incendios forestales para los fullerenes del límite K-T.
Principales métodos:
- La cromatografía líquida a alta presión (HPLC) se utilizó para la separación.
- El análisis espectral ultravioleta visible (UV-Vis) identificó C60.
- La extracción de tolueno se empleó para la preparación de muestras.
Principales resultados:
- C60 se detectó en el hollín límite K-T de los sitios de Nueva Zelanda.
- Las concentraciones de fullereno oscilaron entre 0,1 y 0,2 partes por millón.
- Se encontraron cantidades similares de fullereno en el hollín de las llamas comunes.
Conclusiones:
- Los fullerenos en las capas límite K-T podrían originarse en incendios forestales.
- Los incendios forestales asociados con el evento de impacto K-T son una fuente plausible.
- Esto desafía las explicaciones basadas únicamente en el impacto para los fullerenes de límite K-T.
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