Sylwester J. Rzoska

Bio: Sylwester J. Rzoska is an academic researcher from Polish Academy of Sciences. The author has contributed to research in topics: Dielectric & Liquid crystal. The author has an hindex of 33, co-authored 216 publications receiving 3570 citations. Previous affiliations of Sylwester J. Rzoska include University of Silesia in Katowice & Silesian University.

Nonlinear dielectric effect in liquids in the vicinity of the critical point

Abstract: Results of systematic investigations carried out in our laboratory on the nonlinear dielectric effect (NDE) in the critical mixtures of liquids and of liquid crystals are discussed and systematized. The objective of these studies was to determine experimentally the parameters of the critical NDE and to attempt to apply this research method to an examination of various aspects of critical phenomena. Also discussed are the most recent results.

Temperature Studies of Dielectric Permittivity and Mass Density Pretransitional Anomalies in Binary Mixtures

Abstract: Results of temperature studies of dielectric permittivity and mass density in binary mixtures are presented. The anomaly of dielectric permittivity as a function of temperature in nitrobenzene-n-alkanes binary mixtures has been studied. Molar dielectric permittivity which takes into account the anomaly of dielectric permittivity and the mass density anomaly has been introduced.

Viscosity, relaxation time, glass temperature, melting temperature and fragile-to-strong transition parameterizations at extreme pressures in soft-matter systems

Abstract: This contribution presents the extended, pressure-related Vogel–Fulcher–Tammann equation applied to portray the pressure evolution of viscosity η (P) and the related dynamic properties, such as the primary relaxation time τ (P), in soft-matter systems as well as the modified Simon–Glatzel-type equation for describing pressure dependences of the glass temperature T g (P), the melting temperature T m (P) and the fragile-to-strong dynamical transition in confined water T d (P). Both equations are capable of penetrating the negative pressure (isotropically stretched liquid) domain, and at very high pressures are capable of the inverse behavior. They have the following forms: (i) η (P)=η0 exp [D P Δ P/(P 0−P)]=η0 exp [(D P P−D P P SL)/(P 0−P)], where P 0 is the estimate of the ideal glass temperature, P SL is for the stability limit at negative pressures and D P denotes the pressure fragility strength coefficient and (ii) , where and are the reference temperature and pressure,−π is the negative pressure asympt...

The tricritical point in an ethanediol-nitroethane-cyclohexane-methanol solution

Abstract: Applying the polythermal method the coexistence region of three liquid phases in an ethanediol-nitroethane-cyclohexane-methanol system has been found for several temperatures. From this the temperature and composition of the tricritical point has been determined as T TCP = 37.5 ± 1°C and mass fraction :x ethanediol = 0.09 ± 0.01, x nitroelhane = 0.45 ± 0.01 x cycelohcexane = 0.40 ± 0.02, x methanol = 0.060 ± 0.005. The point at which, for a given polytherm, the transition from a two-phase to a three-phase region takes place at the highest temperature is identified as the critical end-point. Functions of temperature versus heights of menisci separating the individual phases have been determined for selected values of concentration.

Classification of secondary relaxation in glass-formers based on dynamic properties.

Abstract: Dynamic properties, derived from dielectric relaxation spectra of glass-formers at variable temperature and pressure, are used to characterize and classify any resolved or unresolved secondary relaxation based on their different behaviors. The dynamic properties of the secondary relaxation used include: (1) the pressure and temperature dependences; (2) the separation between its relaxation time τβ and the primary relaxation time τα at any chosen τα; (3) whether τβ is approximately equal to the independent (primitive) relaxation time τ0 of the coupling model; (4) whether both τβ and τ0 have the same pressure and temperature dependences; (5) whether it is responsible for the “excess wing” of the primary relaxation observed in some glass-formers; (6) how the excess wing changes on aging, blending with another miscible glass-former, or increasing the molecular weight of the glass-former; (7) the change of temperature dependence of its dielectric strength Δeβ and τβ across the glass transition temperature Tg; ...

Supercooled dynamics of glass-forming liquids and polymers under hydrostatic pressure

Abstract: An intriguing problem in condensed matter physics is understanding the glass transition, in particular the dynamics in the equilibrium liquid close to vitrification Recent advances have been made by using hydrostatic pressure as an experimental variable These results are reviewed, with an emphasis in the insight provided into the mechanisms underlying the relaxation properties of glass-forming liquids and polymers