139 research outputs found
Variational Approach to Hard Sphere Segregation Under Gravity
It is demonstrated that the minimization of the free energy functional for
hard spheres and hard disks yields the result that excited granular materials
under gravity segregate not only in the widely known "Brazil nut" fashion, i.e.
with the larger particles rising to the top, but also in reverse "Brazil nut"
fashion. Specifically, the local density approximation is used to investigate
the crossover between the two types of segregation occurring in the liquid
state, and the results are found to agree qualitatively with previously
published results of simulation and of a simple model based on condensation.Comment: 10 pages, 3 figure
Universal law of fractionation for slightly polydisperse systems
By perturbing about a general monodisperse system, we provide a complete description of two-phase equilibria in any system which is slightly polydisperse in some property (e.g., particle size, charge, etc.). We derive a universal law of fractionation which is corroborated by comprehensive experiments on a model colloid-polymer mixture. We furthermore predict that phase separation is an effective method of reducing polydispersity only for systems with a skewed distribution of the polydisperse property
Projected free energies for polydisperse phase equilibria
A `polydisperse' system has an infinite number of conserved densities. We
give a rational procedure for projecting its infinite-dimensional free energy
surface onto a subspace comprising a finite number of linear combinations of
densities (`moments'), in which the phase behavior is then found as usual. If
the excess free energy of the system depends only on the moments used, exact
cloud, shadow and spinodal curves result; two- and multi-phase regions are
approximate, but refinable indefinitely by adding extra moments. The approach
is computationally robust and gives new geometrical insights into the
thermodynamics of polydispersity.Comment: 4 pages, REVTeX, uses multicol.sty and epsf.sty, 1 postscript figure
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Examination of the Singapore Shift in Japan's Foreign Direct Investment in Services in ASEAN
Finite-size dependence of the bridge function extracted from molecular dynamics simulations
International multi-party projects: the importance of negotiating process in cross-border contractual relationships
Signalling Demand for Foreign Investment: Postsocialist Countries in the Global Bilateral Investment Treaties Network
A unique dataset on bilateral investment treaties provides a novel source of evidence on the link between neoliberal globalisation and market transition. We argue that postsocialist countries of Europe and Eurasia, more than other developing regions in the world, signed such treaties to signal demand for foreign investment in the spirit of neoliberalism. We calculated the density of the whole BIT network since its inception in 1959 to 2009, and density and centrality of different regional blocks within it, and found strong support for our argument. Yet, even if bilateral investment treaties are designed to promote foreign direct investment, dynamic panel regression models show that signing them does not automatically translate into foreign direct investment inflows for postsocialist European and Eurasian countries in the 1990–2010 period
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