For as long as X-ray astronomy exists X-ray (and gamma-ray) astronomers consider the Crab supernova remnant to be a steady standard candle suitable as a calibration source. INTEGRAL has been observing
Sandford R. Holdahl, William E. Strange, Robert J. Harris. Also available online in PDF. Bibliography: p. 23. 1986 NOS (National Ocean Service) Library Public Domain 1935
ABSTRACT This work evaluated the influence of the viscosity of the alkaline activator solution on the workability of geopolymeric mortars. For this, eight mortars were made using commercial metakaolin
