We calculate tractable microscopic expressions for the low-shear normal-stress coefficients of colloidal dispersions. Although restricted to the low rate regime, the presented formulas are valid for all volume fractions below the glass transition and for any interaction potential. Numerical results are presented for a system of colloids interacting via a hard-core attractive Yukawa potential, f...

Stimuli-sensitive hydrogel microspheres or microgels are polymeric particles that consist of cross-linked three-dimensional networks. They shrink or swell significantly by expelling or absorbing large amounts of water in response to external stimuli, such as changes in temperature, pH, electric or magnetic fields. The chemical composition of the microgel determines the stimulus that can trigger...

A theoretical model of polyelectrolyte gels is presented to study continuous and discontinuous volume phase transitions induced by changing salt concentration in the external solution. Phase diagrams are constructed in terms of the polymer–solvent interaction parameters, external salt concentration, and concentration of fixed charges. Comparisons with previous experiments for an ionized acrylam...

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We report a novel experimental study on the jamming transition of dry fine powders with controlled attractive energy and particle size. Like in attractive colloids dry fine particles experience diffusion-limited clustering in the fluidlike regime. At the jamming threshold fractal clusters crowd in a metastable state at volume fractions depending on attractive energy and close to the volume frac...

By examining rapid changes in the volume and temperature during excitation of a large number of excitable cells and tissues, we have shown that the excitation process is invariably accompanied by swelling and heat production in the superficial protoplasmic layer. By comparing the behavior of a model system (synthetic anionic gels containing both Caand Naions) with that of nerve fibers under com...

Magnetic, linear thermal expansion (LTE), anisotropic (λt) and volume (ω) magnetostriction properties of Pr0.5Sr0.5MnO3 were investigated. The LTE decreases smoothly from 300 K without a clear anomaly either around the Curie (TC = 270 K) or the Neel temperature (TN = 100 K) and it exhibits hysteresis over a wide temperature range (60 K-270 K) upon warming. Isothermal magnetization study suggest...

We consider a temperature driven first-order phase transition describing the coexistence of q ordered low-temperature phases and one disordered high-temperature phase at the infinite volume transition temperature T0. Analysing the exponential corrections to the usual heuristic formula of the periodic partition function in a box of volume V, Zper = ∑ m exp(−βfmV ), where β = 1/kBT and fm is the ...