Submitted for the MAR10 Meeting of The American Physical Society Phase equilibria in polymer-blend thin films NIGEL CLARKE, MIREILLE SOUCHE, Durham University — To describe equilibrium concentration profiles in thin films of polymer mixtures, we propose a Hamiltonian formulation of the Flory-Huggins-de Gennes theory describing a polymer blend thin film. We first focus on the case of 50:50 polym...

Based on hard-sphere limit of binary mixtures with different molecular size of components a theory has been developed for calculating activities of solvents in polymer/solvent mixtures. The theory considers various chain configurations for polymer molecules, varying from extended chain to the coiled chain. According to this theory the activity of solvent can be calculated from molecular weights...

The thesis is that every sequential algorithm, on any level of abstraction, can be viewed as a sequential abstract state machine [Gurevich 1985, 1991]. Abstract state machines (ASMs) used to be called evolving algebras. The sequential ASM thesis and its extensions [Gurevich 1995] inspired diverse applications of ASMs. The early applications were driven, at least partially, by the desire to test...

An oscillatory capillary rheometer was used to investigate the effects of NaCl, KCl, and CaCl2 on visco-elastic properties of xanthan and locust bean gum (LBG) blends in dilute solution. Gums were evaluated for intrinsic viscosity and elastic component. Molecular conformation of the xanthan–LBG complex was assessed by the power-law and Huggins equations. Addition of any of the three salts reduc...

We describe a general strategy, PERM (Pruned-Enriched Rosenbluth Method), for sampling configurations from a given Gibbs-Boltzmann distribution. The method is not based on the Metropolis concept of establishing a Markov process whose stationary state is the wanted distribution. Instead, it starts off building instances according to a biased distribution, but corrects for this by cloning “good” ...

the classic Huggins model (iO) to 6†" 9/animal in our model. The endocrine and morphological characteristics of the tumors induced by our protocol are identical to those ofthe Huggins model. Animals were randomly placed into control and TAM groups. Two experimental protocols were developed (Fig. 1). In the first, TAM (10 mg/kg body weight in 1 ml sesame oil s.c.) was injected simultaneously w...

The gas separation performance of biopolymers is still scarcely characterized, mostly because their poor thermomechanical properties and high crystallinity which associated to low permeability. In this work we characterize the transport in a poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) random copolymer, that has relatively good mechanical properties, combined with renewable origin, biodegrad...

The physicochemical properties, cationic composition and rheological behaviour of exudates from Ficus glumosa were investigated. The gum was found to be mild acidic, ionic and soluble in water but insoluble in organic solvents. The trend for the decreasing concentration of elements determined in the gum sample is Mg > Ca > Mn > Zn > Fe > Ni > Cu > Cd > Pb. Rheological properties of the gums hav...

Meet Dr. Tom Levy (who changed the status of U.S. Vitamin C usage after his best selling book and presentation to us last year. Now he intends to change the status of Calcium usage worldwide, after this presentation and new book due out in December).Dr. Levy received his Bachelor of Arts degree in biology from the Johns Hopkins University in 1972. He later graduated from the Tulane University S...

Thermoresponsive polymer segments have been reported to induce lateral microphase separations due their switching transitions from a hydrophilic state hydrophobic one in hydrogels, which result shrinkage and collapse of the networks significantly improved mechanical strength. However, route are assembled into micelles during separations, thermoresponsive toughening mechanisms not fully understo...