Portable High Energy Gamma Ray Imagers

To satisfy the needs of high energy gamma ray imagers for industrial nuclear imaging applications, three high energy gamma cameras are presented. The RMD-Pinhole camera uses a lead pinhole collimator and a segmented BGO detector viewed by a 3 inch square Position Sensitive Photomultiplier Tube (PSPMT). This pinhole gamma camera displayed an energy resolution of 25.0% FWHM at the center of the camera at 662 keV and an angular resolution of 6.2 ffi FWHM at 412 keV. The fixed multiple hole collimated camera (FMCC), used a multiple hole collimator and a continuous slab of NaI(Tl) detector viewed by the same PSPMT. The FMCC displayed an energy resolution of 12.4% FWHM at 662 keV at the center of the camera and an angular resolution of 6.0 ffi FWHM at 412 keV. The rotating muliple hole collimated camera (RMCC) used a 180 ffi antisymmetric rotation modulation collimator and CsI(Tl) detectors coupled to PIN silicon photodiodes. The RMCC displayed an energy resolution of 7.1% FWHM at 662 ..

One-year observation on the population structure of Diopatra neapolitana Delle Chiaje (Polychaeta : Onuphidae) in Izmir Bay (Aegean Sea, eastern Mediterranean)

WOS: 000234482700014The present paper deals with the morphology and population structure of Diopatra neapolitana collected in Izmir Bay between July 1997 and June 1998. The density of the species in the area ranged from 42 ind(.)m(-2) (November 1997) to 198 ind(.)m(-2) (March 1998), the biomass from 84 g(.)m(-2) (November) to 408 g(.)m(-2) (March). The coelom contained gametes in all months, except for January, indicating that it has a very long reproductive period in the area. The relationships among the biometrical measurements taken on specimens of Diopatra neapolitana from Izmir Bay were assessed by using regression and correlation analysis. A re-description of the species is provided