RESUMO
A template-matching procedure is being investigated for rapid detection of improvised explosive devices at standoff distances. Photon-scattered and photon-induced positron annihilation radiation responses are being studied as a part of a signature-based radiation scanning approach. Back-streaming radiation responses, called signatures, are compared to templates, which are collections of the same signatures if the interrogated volume contained a significant amount of explosive. Experiments have been conducted that show that explosive surrogates (fertilizers) can be distinguished from several inert materials.
Assuntos
Algoritmos , Substâncias Explosivas/análise , Substâncias Explosivas/química , Reconhecimento Automatizado de Padrão/métodos , Análise Espectral/métodos , FótonsRESUMO
Next to oxygen silicium is the most common substance of our environment. It occurs mostly in form of quartz (SiO2). In the past silica was usually mentioned in connection with foreign body granulomas in dermatological papers. Recently relations between occupational silica exposure and several diseases were reported. Silica exposure was related to the development of scleroderma, lupus erythematodes and sarcoidosis. Pathogenetic connections may be due to a stimulating effect on fibroblasts and due to immunmodulating properties of silica.