29 research outputs found
The origin of correlation between mass and angle in quasi-fission
Mass-angle distribution (MAD) measurement of heavy and superheavy element
fragmentation reactions is one of the powerful tools for investigating the
mechanism of fission and fusion process. MAD shows a strong correlation between
mass and angle when the quasi-fission event is dominant. It has characteristic
that appears diagonal correlation as long as the quasi-fission event is
dominant. This diagonal correlation could not be reproduced in previous our
model before the introduction of the parameters. In this study, we
systematically evaluate the unknown model parameters contained in our model and
clarify those model parameters to reproduce the diagonal correlation that
appears in MAD. Using a dynamical model based on the fluctuation dissipation
theorem that employs Langevin equations, we calculate MADs of two reaction
systems Ti+W and S+Th which are dominated by
quasi-fission. We were able to clarify the effects of unknown model parameters
on the MAD. In addition, we identified the values of model parameters that can
reproduce the correlation between mass and angle. As a result, it was found
that the balance of tangential friction and moment of inertia values is
important for the correlation between mass and angle.Comment: 5 pages, 2 figures, SND2020. arXiv admin note: text overlap with
arXiv:2309.11095, arXiv:2310.02547, arXiv:2310.0721
Measurement of fission-fragment mass distributions in the multinucleon transfer channels of the reaction
International audienceFission-fragment mass distributions for 23 nuclei (U234â237, Np236â239, Pu238â241, Am240â243, Cm242â245, and Bk244â246) were measured using the multinucleon transfer approach in the reaction of O18+Np237, and their excitation-energy dependence was obtained up to a maximum of 70Â MeV. Among them, the low-energy fission of Np236, Pu238, and Cm245 is reported for the first time. The experimental data for all the studied nuclei were compared to the Langevin calculations. The calculation which takes into account the effects of multichance fission well reproduced the peak-to-valley ratio and mass-asymmetric peak positions of the distributions. The angular momentum given to the fissioning nucleus is also discussed
Investigation into the supramolecular properties of fibres regenerated from cotton based waste garments
This paper investigated the supramolecular properties and accessibility of fibres regenerated from cotton-based waste garments and compared to typical lyocell fibres. The supramolecular and accessibility properties of the cotton-based waste garments fibres regenerated from three sources (waste denim garments, easy care finished cotton fabrics and a blend of cotton-based waste garment with wood pulp) were analyzed and compared to the lyocell fibres. The Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy and Wide Angle X-ray Diffraction (WAXD) analyses indicated that the fibres from cotton waste garments had supramolecular properties similar to the typical lyocell fibres. The exception was spun from the cotton pulp reclaimed from easy care treated cotton fabrics and maybe related to increased amorphous cellulose content in its structure. The fibreâs accessibility by reagents behaviour correlated well with the supramolecular properties. The results indicate that the waste garment purification process may affect the properties of the pulp and hence the supramolecular properties of the resultant fibres. Further research on the purification and regeneration of fibres from waste garments may lead to the use of cotton waste garments as an alternative feedstock source to the lyocell process