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Radiological characterization of the GRR-1 pool  

International Nuclear Information System (INIS)

GRR-1 is a 5MW open pool type research reactor with MTR-type fuel elements cooled and moderated by light water with beryllium reflectors at the two opposing sides of the core. A graphite thermal neutron column is adjusted to one side of the core. Six radial horizontal beam tubes are available, of which three contain in-pile collimators for neutron scattering instruments. The reactor is currently out of operation for inspection and refurbishment purposes. The core has been dismantled and the fuel elements are stored in the used fuel storage tank. The GRR-1 inspection and refurbishment plan involves inspection and eventually replacement of the reactor's primary cooling circuit. The health physics procedures to be implemented during inspection of the main water outlet are divided in three stages: a) pool dose rate survey from pool top, b) pool drainage by decreasing water level in steps and c) inspection of the water main outlet. urpose of the ...

2007-11-05

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Lecturas neobarrocas del Espejo de paciencia y reconceptualizaciones de la naci?n: Jos? Lezama Lima, Cintio Vitier y Severo Sarduy  

British Library Electronic Table of Contents (United Kingdom)

This article examines the successive reinterpretations of one of Cuba?s foundational texts, namely the Espejo de paciencia (?Model of Patience??, 1608) by Silvestre de Balboa, as a baroque poem. The revalorization of the baroque by twentieth-century Cuban authors and critics has been explained as a consequence of the erasure of indigenous cultures and the subsequent imposition of a metropolitan culture. In this sense, the baroque is supposed to be paradigmatic for ?roots thinking?? about nation-building and culture. The readings of Balboa?s poem by neo-baroque writers such as Jos? Lezama Lima, Cintio Vitier and Severo Sarduy, however, put forward a transhistorical vision of the baroque and Cubanhood as an eternal and immutable phenomenon or, alternatively, a reading that privileges the tec...

2010-01-01

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Relativistic corrections to the spectra and radiative transitions in quarkonia  

International Nuclear Information System (INIS)

The author calculated the wavefunctions and the energy-spectra of c bar c and b bar b bound systems using the Hamiltonian proposed by Gupta, Radford and Repko (GRR). He writes the GRR Hamiltonian as H = H_o + H', where H_o includes the kinetic energy terms and the most dominant terms in the Hamiltonian. H' includes among other things the spin-spin, spin-orbit and the tensor terms in the Hamiltonian. The eigenvalue problem of H_o is solved by the variational method which makes use of a trial wave-function with eleven parameters. H' is then treated in the first order perturbation theory. The energy-spectra agree very well with experimental data. He also calculated the E1 and the M1 decay rates of these quarkonia. With relativistic corrections, the E1 transitions agree better with experiment. The dominant relativistic correction comes from the relativistic modification of the wave-function. The M1 transitions can be improved by using a large quark ...

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Large sample NAA facility at GRR-1 research reactor: Design and applications  

International Nuclear Information System (INIS)

Full text: A Large Sample Neutron Activation Analysis (LSNAA) facility is under development at GRR-1 research reactor, NCSR 'Demokritos'. The LSNAA facility design incorporates sample irradiation in the reactor's graphite thermal neutron column and subsequent measurement of the activity induced at a gamma spectroscopy system with gamma ray transmission measurement options included. Monte Carlo neutron and photon transport code MCNP-4C was used to model the facility. Appropriate correction factors accounting for neutron field perturbation during sample irradiation, high purity germanium detector efficiency for the volume source and gamma ray self-absorption within the sample itself were derived. The results of the computations were experimentally verified by activation foil measurements for a set of known materials and a range of sample sizes extending up to 10 litters. Moreover, the special issue of large sample analysis of non-homogeneous samples is examined and ...

2003-06-09

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Assessment of groundwater quality in crystalline fractured aquifers in rural agricultural area of the mid-western coastal parts of South Korea  

International Nuclear Information System (INIS)

Full text: Groundwater in rural agricultural area of South Korea is an important source of drinking and agricultural water. The study area is located in mid-western coastal parts and has fractured bedrock aquifers whose lithologies are composed of Jurassic granites, Paleozoic sedimentary rocks, Precambrian schists and gneiss. Bedrock groundwater was slightly alkaline and had electrical conductivity of 40 to 1570 #mu#S/cm with median values of 322 #mu#S/cm. Water types based on major ions showed that Ca-HCO_3 and Ca-CI types are dominant and Na-HCO_3 and Na-CI types are minor. Intense agricultural activities resulted in significant nitrate contamination of groundwater. 22% and 40% of wells have exceeded drinking water standards (DWS) for bedrock and shallow wells, respectively. In coastal areas, slightly saline groundwater is observed for both bedrock and shallow wells. Groundwater in granitic rocks may have higher concentrations of Rn, U and F. Most wells had ...

2010-11-15