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Radicales libres en la estratosfera: una nueva técnica de observación
Science (New York, N.Y.)
|June 14, 1985
Resumen
Un nuevo sistema en globo permite mediciones in situ de especies reactivas en la estratosfera. Este sistema desplegó y recuperó con éxito instrumentos, detectando gases traza en niveles de partes por billón.
Área de la Ciencia:
- Química de la atmósfera La química de la atmósfera
- Ciencia de la estratosfera Ciencia de la estratosfera.
- Desarrollo del Instrumento de Desarrollo.
Sus antecedentes:
- Las especies trazo reactivas estratosféricas son cruciales para la química de la capa de ozono.
- Las técnicas de medición in situ anteriores tienen limitaciones en la sensibilidad y el despliegue.
- Comprender las concentraciones de radicales libres es clave para los procesos estratosféricos.
Objetivo del estudio:
- Introducir un nuevo sistema en globo para observaciones estratosféricas in situ.
- Para demostrar la capacidad de detectar radicales libres en fase gaseosa en concentraciones de partes por billón.
- Para validar la estabilidad y utilidad de la matriz de instrumentos para mediciones atmosféricas.
Principales métodos:
- Despliegue y recuperación de un grupo de instrumentos a través de un filamento de Kevlar desde una plataforma de globo.
- Utilizando una matriz de instrumentos suspendida para una mayor estabilidad durante las mediciones.
- Detección in situ de radicales libres en fase gaseosa y oxígeno atómico.
Principales resultados:
- Despliegue y retracción exitosos del grupo de instrumentos en un rango de 12 km.
- Capacidad demostrada para detectar especies reactivas en trazas a niveles de partes por billón.
- Se lograron mediciones estables de las concentraciones de oxígeno atómico en la estratosfera.
Conclusiones:
- El sistema desarrollado en globo aerostático ofrece un nuevo y eficaz enfoque para las mediciones estratosféricas in situ.
- La sensibilidad y estabilidad del sistema son adecuadas para el estudio de especies reactivas.
- Esta tecnología avanza la capacidad de sondear procesos químicos estratosféricos críticos.
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