Compaction simulator evolution

The first true compaction simulator capable of mimicking the compaction and ejection cycle of a rotary tablet press was reported by Hunter et al. in the 1970s (2), The evolution of such an instrument presented a novel tool for both powder compression research and scale-up of the tableting process. Celek and Marshall report that although compaction simulators are expensive to purchase, they present the following attributes ... 

The influence of the appearance of such exotic states like quarks in stellar matter is topic of the study of quasi-stationary simulations of the evolution of isolated compact stars [15, 12, 7, 23] and accreting systems, where one companion is a superdense compact object [9,27], In this work we investigate the observability of the hadron-quark deconfinement phase transition in the dynamical evolution of a neutron star merger. 

Let us compare the kinetics of the selective-solvent-induced collapse of protein-like copolymers with the collapse of random and random-block copolymers [18]. Several kinetic criteria were examined using Langevin molecular dynamics simulations. There are some general results, which seem to be independent of the nature of interactions or the kinetic criteria monitored during the collapse. Here, we restrict our analysis to the evolution of the characteristic ratio f = (Rgp/Rg ) that combines the partial mean-square radii of gyration calculated separately for hydrophobic and hydrophilic beads, k2n and Rg . This ratio takes into account both the properties of compactness and solubility for a heteropolymer globule [70] (compactness is directly related to the mean size of the hydrophobic core, whereas solubility should be dependent on the size of the hydrophilic shell). 

Figure 24.1. Snapshots from molecular dynamics simulations of oligomerization in aqueous silicic acid with r = 11. Only silica polymorphs containing at least two silicon atoms are shown all silicic acid monomers and water molecules (which completely fill the remainder of the simulation cell) are removed for clarity. Only silicon and oxygen atoms are shown terminal hydrogens have been removed. Snapshots are taken from the simulation at times A. 1.0, B. 2.0, C. 3.0, and D. 4.8 ns. The evolution of small oligomers into compact sol particles is clearly visible. Reprinted with permission from [49]. Copyright 2007 American Chemical Society.

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