Hyperion (Ireland)

Ziel/Aim Currently available clinical PET systems employ detectors where the scintillator is structured into single needles of 3 – 6 mm width. This limits the spatial resolution and causes radial astigmatism at off-center positions as the depth-of-interaction (DOI) cannot be measured. Introducing more finely structured scintillators with DOI capabilities significantly increases the cost and reduces the sensitivity. We present an alternative based on an array of semi-monolithic crystals which are large blocks without segmentation at costs comparable to current detectors. In this design, optical photons travel in the scintillator and create a 3D-dependent light pattern on multiple photosensor channels enabling the position estimation of the 511 keV gamma photons.

In 1987 the Directorate General XII of the CEC started the first Concerted Action on Battery Control and Management in PV Systems to investigate common problems with the operation of batteries in the PV pilot plants. The results of this work stimulated the present concerted action whose objective it is to assist PV plants in overcoming these problems. The work of the concerted action is focused on: Compiling the PV Battery Handbook. Providing practical assistance to the PV pilot plants in order to improve their battery performance and increase its lifetime. Co-ordinating experiments in the PV pilot plants.

In stand alone photovoltaic systems the battery costs can be 25% of the total installed systems costs. The battery lifetime can vary from 4 to 10 years depending on the design and the operation of the systems. Developments in Battery storage for PV will involve improving their reliability, increasing their lifetime and reducing their costs. This paper describes the developments to conventional batteries such as Lead Acid and Nickel Cadmium and new developments such as Sodium Sulphur, Zinc Bromine, Nickel Hydrogen and Solid Lithium. The paper discusses the potential PV applications of these batteries, their current status and their limitations.

In connection with the proposed discharge of sludge from Los Angeles Hyperion Treatment Plant, it was realized that if proper precautions were not taken, some problems might develop in respect to the appearance of rubber particles on the ocean surface. Accordingly a research program was instituted to determine the most effective and economical means of insuring removal of floatable fractions before discharge. This paper describes certain laboratory and pilot plant studies and other investigations leading to the final design of a sludge treatment process intended to prevent problems of this nature.