Skip to main content

4 Result(s)

within H. E. JOHNS Remove this filter

and

  1. Article

    A Direct Measurement of the Energy Locally Absorbed from a Gamma-Ray Beam

    THE energy locally absorbed in a material exposed to γ-radiation has usually been determined indirectly from measurements with an ionization chamber, using the Bragg–Gray formula. The calculation involves the ...

    H. E. JOHNS, J. P. BERNIER, D. V. CORMACK in Nature (1955)

    Download PDF (1647 KB)

  2. No Access

    Article

    Relative Biological Effectiveness of Betatron and Conventional X-Radiation on the Regression of Mouse Tumours

    THE development of more-powerful sources of X-radiation has made possible the investigation of the biological effectiveness of a variety of ionizing radiations. In vitro experiments have suggested that radiations...

    T. P. TING, H. E. JOHNS, L. B. JAQUES in Nature (1952)

  3. No Access

    Article

    1,000-Curie Cobalt-60 Units for Radiation Therapy

    TELETHERAPY units using radium are limited in usefulness by the low radiation intensities produced by the small amounts of radium which can be used. To secure an adequate dosage-rate, the distance between the ...

    H. E. JOHNS, L. M. BATES, E. R. EPP, D. V. CORMACK, S. O. FEDORUK, A. MORRISON… in Nature (1951)

  4. No Access

    Article

    Induction of Mutation by High-Energy X-Radiation Produced by a 23-MeV. Betatron

    WITHIN a wide range of energies (12.4 kV.–2.2 MeV.) X-rays are all about equally efficient in inducing mutation1. The frequency of induced mutations is directly proportional to the dose measured in roentgens1. It...

    HULDA REGEHR, T. J. ARNASON, H. E. JOHNS in Nature (1950)