Authors:I. Gonçalves, A. Ramalho, I. Gonçalves, J. Salgado, J. Pertusa, A. Irles, F. Mascarenhas, M. Castro, F. Valle, J. Rico and V. Alcober
The goal of this work is to pursue the research activity in BNC and the installation of a therapy facility in the position
presently occupied by the thermal column. With these objectives the experimental studies in mice and cells are continuing
while improvements in the facilities are created or prepared. For this effect: (1) the installation of lead shield in the
vertical access of the thermal column, which resulted in an enhancement of the Φth toDγ ratio, was performed, (2) the adaptation of a beam tube to deliver a dominantly thermal or epithermal beam in two possible
beam openings is being done and (3) Monte Carlo calculations aiming at the optimization of the conditions for the therapy
installation are in progress.
Authors:V. Ivanenko, V. Kovalenko, V. Kustov, A. Grigorev and A. Metelev
Results of development of nuclear-physical research installations and methods of ocean bottom sediments analysis using radionuclide sources of neutron, gamma and X-ray radiations are presented. Practical applications of the above developments in expeditionary conditions aboard research vessels are summarized.
Authors:J. Garcia Alonso, D. Thoby-Schultzendorff, B. Giovannone and L. Koch
Inductively Coupled Plasma Mass Spectrometry ICP-MS has been applied to the characterisation of various nuclear waste forms. Long-lived radionuclides can be determined with similar sensitivities. The installation of an ICP-MS in a glove box and applications and limitations of the methods to nuclear materials, with especial emphasis on isobaric interferences are described.
The least expensive chemical methods of stable isotope separation are discussed. Between them are especially known chemical exchanges used for separation of boron, nitrogen and sulfur isotopes, low temperature rectification applied for enriching rare isotopes of carbon and oxygen and cryogenic adsorption served for obtaining very pure deuterium. The most important characteristics of installations, processes and working conditions are represented.
The paper considers the analytical procedure for determination of U and Th isotopes in environmental samples for those cases when coincentrations are on the background levells. The technique includes preconcentration operations with the use of ion-exchange and electrodeposition with the aim to obtain preparations for alpha-spectrometry. The preconcentration allows to use less complicated alpha-spectrometric installations.
The installation of a multi-sample beta-gamma coincidence spectrometer in an underground laboratory with a rock covering of 47 m yielded further background reduction by factors of between 10 (at 2 MeV) and about 4 (below 1 MeV). In silicon samples Fe can be measured by neutron activation analysis with a detection limit of 40 pg.
It is a prime aim to ensure a suitable comfort level in case of office buildings. The productivity of office employees is directly influenced by the comfort. Thermal discomfort and poor indoor air quality deteriorate the intensity and quality of human work. We investigated the comfort in office buildings with on-site measurements during the summer season. The office buildings were operating with different HVAC (Heating, Ventilating and Air-Conditioning) systems: ducted fan-coil with suspended ceiling, installation, non-ducted fan-coil with floor-mounted installation, active chilled beam with fresh air supply.
We evaluated the thermal comfort under PMV (Predicted Mean Vote), PPD (Predicted Percentage of Dissatisfied), the local discomfort based on DR (Draught Rate) and the IAQ (Indoor Air Quality) based on carbon dioxide concentration. The comfort measurements were evaluated. The measurements were evaluated with scientific research methods, comfort categories based on the requirements of CR 1752. The results of this comparison were presented in this article.
An installation for photon activation analysis recently completed at CBNM, Geel, is described. Synthetic standards prepared
from pure graphite are used for the non-destructive determination of lanthanides in boron carbide. The induced activities
of153Sm,152mEu,159Gd and157Dy were measured using a single open-ended coaxial Ge(Li) detector and the photopeak areas were calculated using the GAFIT
program. For the irradiation parameters used, the limits of detection are communicated.
A debate has occurred recently over the issue whether it is possible to account for differences in results when using various versions of theScience Citation Index for the measurement of national performance in terms of numbers of scientific publications. This article provides an overview of the various arguments which have been made, and reports that recent reorganization in the on-line installations (SciSearch) should make it possible to circumvene one of the major sources of error.