In this work, we will study the relative contribution of each of the two dissipative channels of the Eriksen, Leslie, and Parodi (ELP) approach to the observed values of the Miesowicz viscosity coefficients of the nematic liquid crystals. According to the fundamental equation of the liquid crystal's viscosity dissipative process, TS=-integral d3r(sigma)ijA(ij)+hxN , there are two channels by which the nematic viscous dissipation can occur: or it occurs by means of a shear flow configuration, where A(ij) is the characterizing term, or it occurs by means of a rotational configuration, where N is the characterizing term (these parameters will be defined in the paper). It will be also shown that this relative contribution can be measured by a simple relationship connecting the Miesowicz coefficients, which exhibits a quasitemperature independent behavior, suggesting that it is nearly constant through the entire domain of the nematic phase.

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Water, which is essential for the existence of life, has almost a hundred properties that distinguish it from other liquids.In this paper, we will focus on its density, which, unlike the absolute majority of other liquids, increases with increasingtemperature in the vicinity of the solid-liquid transition, for a wide range of pressures, including ambient pressure. Ourapproach will present an analytical thermodynamic formulation for this problem that has as a novelty the introductionof a variable exclusion volume. We will consider the excluded volume a thermodynamic variable that depends onthe system's thermal conditions. This approach will be applied to the two-liquid theory of water, which claims thatwater molecules can be assembled into two different kinds of clusters. At a given state, the relative numbers of theseaggregates can be very sensitive to thermal variations, and, as the excluded volume for each of them is different, whentheir relative number changes, the total excluded volume also changes. We will show how to gather the ideas of a nonconstant excluded volume with the two-liquid theory of water into a new, elegant and non-trivial analytical expression for the density of water. In the end, we compare our expression with experimental data and show that it provides an exact understanding of the anomalous behavior of water density.

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In this work, the effective viscosity of the cholesteryl myristate and cholesteryl nonanoate liquid crystals is studied as a function of temperature at the region of their cholesteric-to-isotropic phase transition, where blue phases are found. Using a change of scale it is shown that the viscosity peaks that characterize these phase transitions are shape invariant, which suggests that large-scale fluctuations on the two-point correlation function give an important contribution to the observed viscosity. The consequences of this fact are investigated and, from the experimental data, the critical exponents associated with the diverging two-point correlation function are calculated. The results found for both compounds are essentially the same, being also in good agreement with the known values of the corresponding critical exponents of nematic-isotropic phase transition.