471 research outputs found
Systems of innovation
We review the literature on national innovation systems. We first focus on the emergence of the concept of innovation systems, reviewing its historical origins and three main flavours (associated to three “founding fathers†of the concept). After this, we discuss how the notion of innovation systems filled a need for providing a broader basis for innovation policy. We conclude with some perspectives on the future of the innovation systems literature.
Novel Technique for Ultra-sensitive Determination of Trace Elements in Organic Scintillators
A technique based on neutron activation has been developed for an extremely
high sensitivity analysis of trace elements in organic materials. Organic
materials are sealed in plastic or high purity quartz and irradiated at the
HFIR and MITR. The most volatile materials such as liquid scintillator (LS) are
first preconcentrated by clean vacuum evaporation. Activities of interest are
separated from side activities by acid digestion and ion exchange. The
technique has been applied to study the liquid scintillator used in the KamLAND
neutrino experiment. Detection limits of <2.4X10**-15 g 40K/g LS, <5.5X10**-15
g Th/g LS, and <8X10**-15 g U/g LS have been achieved.Comment: 16 pages, 3 figures, accepted for publication in Nuclear Instruments
and Methods
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