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The fission cross section of 245Cm was measured at the GELINA neutron facility of the Institute for Reference Materials and Measurements (IRMM) in Geel, Belgium, as a function of the incident neutron energy. The energy of the neutrons is determined applying the time of flight method using a flight path length of about 9 m. A highly enriched 245Cm sample (98.48%) was mounted back-to-back with a 10B sample in the centre of a vacuum chamber together with two surface barrier detectors positioned outside the neutron beam. One detector measured the 10B(n,α)7Li reaction products for the neutron flux determination, while the second one registered the 245Cm(n,f) fragments. A control measurement has been performed replacing the 245Cm sample with a 235U sample in order to check that the well-known 235U(n,f) cross section can be reproduced. In comparison with previous 245Cm fission cross section measurements, our preliminary results show a nice improvement of the energy resolution, in particular below 20 eV where very few data are available. [ABSTRACT FROM AUTHOR]

During the last years, several Cm and Cf isotopes have been studied by our research group in the frame of a systematic investigation of gas emission characteristics in ternary fission. Here we report on new results on the energy distribution and the emission probability of 3H, 4He and He particles emitted in the spontaneous ternary fission of 250Cf (Eexc = 0 MeV) and in the neutron induced ternary fission of 249Cf (Eexc = 6.625 MeV). Both measurements were performed using suited and well-calibrated ΔE-E telescope detectors, at the IRMM (Geel, Belgium) for the spontaneous fission and at the very intense neutron beam PF1b at the Institute Laue-Langevin (Grenoble, France) for the neutron induced fission measurement. In this way, the existing database can be enlarged with new results for Z = 98 isotopes, which is important for the systematic investigation. Moreover, the investigation of the ‘isotope couple’ 249Cf(n,f)–250Cf(SF), together with corresponding data for other isotopes, will yield valuable information on the influence of the excitation energy on the particle emission probabilities. [ABSTRACT FROM AUTHOR]

Ternary fission is an important source of He and tritium gas in nuclear reactors and used fuel elements. Therefore a systematic study of the ternary fission yields for 4He and tritons (t) is being performed. In recent years the influence of the excitation energy of the fissioning nucleus on the triton emission probability (t/B) has been investigated for different Cm and Cf isotopes. In this paper we report on new results on the neutron induced fission of 243Cm. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

We look at the gut as the biggest interface between an organism and its environment. Guts are responsive to many external conditions (food availability, pathogen pressure and nutritional demands), whilst at the same time serving internally orchestrated seasonal fitness functions. In our work on the ecology and evolution of shorebirds, i.e. seasonal migrants that travel the length and with of the globe but with distinct habitat preferences, we have taken the gut as a consequential and fully integrated part of the organism-environment interaction. We will review how different parts of the gut respond to changes in food quality and demand, even representing strategic design solutions to challenges and habitats encountered next. Our prime example are molluscivore specialists (especially red knots, Calidris canutus) that in some conditions trade a hard-shell-processing against a food-toxin constraint. A novel level of organismal integration is suggested by the finding that personality differences between individuals correlate with gut size in seemingly adaptive ways. [ABSTRACT FROM AUTHOR]