Biomedical subjects

MD Rintoul

Publications and source records attributed to MD Rintoul.

8 recordsLinked to original sources

PubMed2000

Precise determination of the void percolation threshold for two distributions of overlapping spheres

The void percolation threshold is calculated for a distribution of overlapping spheres with equal radii, and for a binary-sized distribution of overlapping spheres, where half of the spheres have radii twice as large as the other half. Using systems much larger than previous work, we determine a much more precise value for the percolation thresholds and correlation length exponent. The value of the percolation threshold for the monodisperse case is shown to be 0. 0301+/-0.0003, whereas the value for the bidisperse case is shown to be p(c)=0.0287+/-0.0005. The fact that these are significantly different is in contrast with previous, less precise works that speculated that the threshold might be universal with respect to sphere size distribution.

Journal Article↗

PubMed1997

Reconstruction of the Structure of Dispersions

To what extent can the structure of a disordered heterogeneous material be reconstructed using limited but essentially exact structural information about the original system? We formulate a methodology based on simulated annealing to reconstruct both equilibrium and non-equilibrium dispersions of particles based only on correlation functions which statistically characterize the system. To test this method, we reconstruct dispersions from the radial distribution function (RDF) associated with the original system. Other statistical correlation functions are evaluated to compare how well the reconstructed system matches the original system. We show that for low-density systems or high-density systems with little particle aggregation, our reconstruction from the RDF reproduces the system fairly well. However, for dense systems with extensive clustering, RDF information is somewhat inadequate in being able to reconstruct the original system. We also show that one can produce a system with an RDF that is similar to the reference system, but with appreciably different structure. Finally, system-size effects are analyzed analytically.

Journal Article↗

PubMed1996