The aptitude of a hollow-fiber membrane reactor to determine lipase kinetics was investigated using the hydrolysis of triacetin catalyzed by lipase from Canadida cylindracea as a model system. The binding of the lipase to the membrane appears not to be very specific (surface adsorption), and probably its conformation is hardly altered by immobilization, resulting in an activity comparable to th...

One way to explore exotic nuclei is to study their structure by performing -ray spectroscopy. At the ILL, we exploit a high neutron flux reactor to induce the cold fission of actinide targets. In this process, fission products that cannot be accessed using standard spontaneous fission sources are produced with a yield allowing their detailed study using high resolution -ray spectroscopy. This i...

A natural nuclear fission reactor with a power output of 3-to 10 Terawatt at the center of the earth has been proposed as the energy source of the earth’s magnetic field. The proposal can be directly tested by a massive liquid scintillation detector that can detect the signature spectrum of antineutrinos from the geo-reactor as well as the direction of the antineutrino source. Such detectors ar...

1. Reactor Kinetics 1.

Vaporization of fission products and certain other materials is estimated for the extreme environmental conditions projected for severe reactor accidents. Partial pressures of gaseous species are calculated from thermochemical data or estimates. Mounts of vapor transported material are evaluated from projected gas flows during two phases of a hypothetical accident--( a) core dry out phase and (...

One of the techniques of minor actinides transmutation is to recycle these nuclides into fission reactors. Two concepts of a minor actinides burner reactor with very hard neutron energy spectrum as well as very high neutronjlux me discussed. The fuel cycle facilities for these burner reactors am assessed to discuss the technical feasibili~ of these reactors. Transmutation of minor actinide in b...

A mesoscale model is developed by integrating the rate theory and phase-field models and is used to study the fission-induced recrystallization in U-7Mo alloy. The rate theory model is used to predict the dislocation density and the critical size and density of the recrystallized nuclei due to irradiation. The predicted fission rate and temperature dependences of the dislocation density are in ...

The Monte Carlo calculation of the effective (i.e. adjoint weighted) neutron generation time Keff, especially for continuous energy simulations, is not straightforward nor standard in Monte Carlo codes. The use of the non-adjoint weighted neutron generation time K (standard in most Monte Carlo codes) as an approximation of the effective one can lead to a serious bias. We show here that the diff...