Fission product kinetic energies were measured by the double-energy method for thermal-neutron fission of 2359233U and proton-induced fission of 238U at the 15.8-MeV excitation. From the obtained energy-mass correlation data, the kinetic-energy distribution was constructed from each mass bin to evaluate the first moment of the kinetic energy for a given fragment mass. The resulting kinetic energy was then converted to the effective distance between the charge centers at the moment of scission. The effective distances deduced for the proton-induced fission was concluded to be classified into two constant values, one for asymmetric and the other for symmetric mode, irrespective of the mass though an additional component was further extracted in the asymmetric mass region. This indicates that the fission takes place via two well-defined saddles, followed by the random neck rupture. On the contrary, the effective distances obtained for thermal-neutron induced fission turned out to lie along the contour line at the same level as the equilibrium deformation in the twodimensional potential map. This strongly suggests that it is essentially a barrier-penetrating type of fission rat her than the over-barrier fission. KEYWORDS: nuclear fission, uranium

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We carried out molecular dynamics simulations of water infiltration into a slit pore for the understanding of the rinsing process of semiconductors, whose minimum length scale seemingly reached the continuum limit. The possibility of water infiltration strongly depended on the wettability, i.e., the sign of the cosine of contact angle due to the large Laplace pressure. The time needed for the infiltration was small due to the high meniscus velocity, and the gas molecules remaining in the slit did not have remarkable effects on this process. Macroscopic relations gave reasonable estimates for these static and dynamic processes even at the nanoscale.

The title compound, C4H6ClNOS·H2O, has a planar five‐membered ring, with a delocalized positive charge. A three‐dimensional network is formed through inter­molecular O—H⋯O and O—H⋯Cl hydrogen bonds between 3‐hydr­oxy‐2‐methyl­isothia­zolium cations and water mol­ecules, and between water mol­ecules and chloride anions.

Fission product kinetic energies were measured by the double-energy method for thermal-neutron fission of 2359233U and proton-induced fission of 238U at the 15.8-MeV excitation. From the obtained energy-mass correlation data, the kinetic-energy distribution was constructed from each mass bin to evaluate the first moment of the kinetic energy for a given fragment mass. The resulting kinetic energy was then converted to the effective distance between the charge centers at the moment of scission. The effective distances deduced for the proton-induced fission was concluded to be classified into two constant values, one for asymmetric and the other for symmetric mode, irrespective of the mass though an additional component was further extracted in the asymmetric mass region. This indicates that the fission takes place via two well-defined saddles, followed by the random neck rupture. On the contrary, the effective distances obtained for thermal-neutron induced fission turned out to lie along the contour line at the same level as the equilibrium deformation in the twodimensional potential map. This strongly suggests that it is essentially a barrier-penetrating type of fission rat her than the over-barrier fission. KEYWORDS: nuclear fission, uranium