The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 08, 1991
Filed:
Sep. 26, 1989
Peter A Stewart, Bristol, GB;
Richard T Skelton, Bristol, GB;
Martin J Allen, Bristol, GB;
Joseph Douglas, Derby, GB;
Rolls-Royce plc, London, GB;
Abstract
Residual core material can be detected inside hollow cast articles using positron emission tomography. Positron radio-isotope material is inducted into any residual core material present by immersing a cast article in an aqueous solution of radio-isotope emitter, for example gallium. Absorbed gallium subsequently emits positrons which are annihilated in collisions with electrons emitting two 511 KeV gamma rays in diametrically opposite directions. The emissions are detected and tracked by a PET camera and the resulting images correlated with a sectioned image of the article as a check on the location of detected core material. Initially a low-dose-rate solution for the purpose of merely establishing the presence of core material is used but a second optional process step introduces a more active solution allowing a PET camera to collect sufficient data to image absorbed isotope.