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Practical superconducting cables used in large scale applications (e.g. magnets for fusion reactor) consist in superconducting filaments embedded in a normal-conducting matrix. The common technique to reduce the eddy-current losses is to twist the wire and the filaments during the manufacture. This also reduces the time-independent proximity effect between the filaments and its associated loss. Currently, the only method for measuring the twist-pitch
Read moreAn inspection procedure to assess the mechanical integrity of the International Fusion Materials Irradiation Facility (IFMIF) capsules and rigs during the irradiation campaign is necessary. Due to its penetration ability and contrast mechanism, the X-ray microtomography is the only known tool that could meet these requirements. In the high flux test module (HFTM) of IFMIF miniaturized specimens are densely packed in capsules. The capsules, which
Read moreThe failure of the cladding of an irradiated nuclear fuel rod can lead to the loss of some -radioactive fission products. Consequently the distribution of these fission products is altered in the cross section of the fuel rod. The modification of the distribution, obtained by Gamma Computed Tomography, is used to determine the integrity of the fuel cladding. The paper reports an experimental result, obtained for a CANDU-type fuel rod, irradiated
Read moreThe maximum likelihood tomographic method is used to reconstruct the radioactive fission products distribution in irradiated fuel pins from a very small number of projections. The method can be used to analyse the behaviour of the nuclear fuel during irradiation and also to obtain an improvement in burn-up estimation. An experimental result, for a CANDU type fuel pin, is reported. A criterion for optimally stopping the iterative algorithm is suggested.
Read moreA comparison of four tomographic methods that can be used to reconstruct the γ-radioactive fission products distribution in irradiated nuclear fuel pins is reported. The comparison is performed by use of numerically generated data from phantoms which model typical distributions observed in CANDU type fuel pins. The influence of the quality of the methods on the burn-up evaluation is studied.
Read moreA tomographic maximum entropy method is used to reconstruct the 3-D distribution of radioactive fission products in irradiated CANDU type fuel pins. The method has been implementated using a system similar to a single photon emission medical tomograph. It is used to study the behaviour of the nuclear fuel during irradiation and also for a Monte-Carlo simulation of the process of emission of gamma rays in order to improve the burn-up estimation. Experimentally
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