16 research outputs found
An energy landscape model for glass-forming liquids in three dimensions
We present a three-dimensional lattice-gas model with trivial thermodynamics,
but nontrivial dynamics. The model is characterized by each particle having its
own random energy landscape. The equilibrium dynamics of the model were
investigated by continuous time Monte Carlo simulations at two different
densities at several temperatures. At high densities and low temperatures the
model captures the important characteristics of viscous liquid dynamics. We
thus observe non-exponential relaxation in the self part of the density
auto-correlation function, and fragility plots of the self-diffusion constant
and relaxation times show non-Arrhenius behavior.Comment: 6 pages, 6 figures, Submitted for proceedings of the 5th IDMRC
Estimating the density scaling exponent of viscous liquids from specific heat and bulk modulus data
It was recently shown by computer simulations that a large class of liquids
exhibits strong correlations in their thermal fluctuations of virial and
potential energy [Pedersen et al., Phys. Rev. Lett. 100, 015701 (2008)]. Among
organic liquids the class of strongly correlating liquids includes van der
Waals liquids, but excludes ionic and hydrogen-bonding liquids. The present
note focuses on the density scaling of strongly correlating liquids, i.e., the
fact their relaxation time tau at different densities rho and temperatures T
collapses to a master curve according to the expression tau propto
F(rho^gamma/T) [Schroder et al., arXiv:0803.2199]. We here show how to
calculate the exponent gamma from bulk modulus and specific heat data, either
measured as functions of frequency in the metastable liquid or extrapolated
from the glass and liquid phases to a common temperature (close to the glass
transition temperature). Thus an exponent defined from the response to highly
nonlinear parameter changes may be determined from linear response
measurements
Post-analytical stability of 23 common chemistry and immunochemistry analytes in incurred samples
Methods for Solving Problems of Discrete Probability
Katedra pravděpodobnosti a matematické statistikyDepartment of Probability and Mathematical StatisticsMatematicko-fyzikální fakultaFaculty of Mathematics and Physic