Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , Pessoal de Saúde , Imunoglobulina G/sangue , Transplante de Rim , Doenças Profissionais/imunologia , SARS-CoV-2/imunologia , Adulto , Biomarcadores/sangue , COVID-19/diagnóstico , COVID-19/epidemiologia , Feminino , Humanos , Imunidade Coletiva , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/diagnóstico , Doenças Profissionais/epidemiologia , Doenças Profissionais/virologia , SARS-CoV-2/isolamento & purificação , Estudos Soroepidemiológicos , Reino Unido/epidemiologiaRESUMO
Split Hopkinson or Kolsky bars are common high-rate characterization tools for dynamic mechanical behaviour of materials. Stress-strain responses averaged over specimen volume are obtained as a function of strain rate. Specimen deformation histories can be monitored by high-speed imaging on the surface. It has not been possible to track the damage initiation and evolution during the dynamic deformation inside specimens except for a few transparent materials. In this study, we integrated Hopkinson compression/tension bars with high-speed X-ray imaging capabilities. The damage history in a dynamically deforming specimen was monitored in situ using synchrotron radiation via X-ray phase contrast imaging. The effectiveness of the novel union between these two powerful techniques, which opens a new angle for data acquisition in dynamic experiments, is demonstrated by a series of dynamic experiments on a variety of material systems, including particle interaction in granular materials, glass impact cracking, single crystal silicon tensile failure and ligament-bone junction damage.