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The landing safety prediction model by integrating pattern recognition and Markov chain with flight data
The role of crosslinking density in surface stress and surface energy of soft solids
Surface stress and surface energy are two fundamental parameters that
determine the surface properties of any materials. While it is commonly
believed that the surface stress and surface energy of liquids are identical,
the relationship between the two parameters in soft polymeric gels remains
debatable. In this work, we measured the surface stress and surface energy of
soft silicone gels with varying weight ratios of crosslinkers in soft wetting
experiments. Above a critical density, , the surface stress was found to
increase significantly with crosslinking density while the surface energy
remained unchanged. In this regime, we can estimate a non-zero surface elastic
modulus that also increases with the ratio of crosslinkers. By comparing the
surface mechanics of the soft gels with their bulk rheology, the surface
properties near the critical density were found to be closely related to
the underlying percolation transition of the polymer networks.Comment: 9 pages, 7 figure
Alpha Decay Width of Po from a quartetting wave function approach
A microscopic calculation of -cluster preformation probability and
decay width in the typical emitter Po is presented.
Results are obtained by improving a recent approach to describe
preformation in Po [Phys. Rev. C 90, 034304 (2014)] implementing
four-nucleon correlations (quartetting). Using the actually measured density
distribution of the Pb core, the calculated alpha decay width of
Po agrees fairly well with the measured one.Comment: 7 pages, 5 figures, 1 table, submitted to Phys. Rev.
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