Phase transition from a d(x(2)-y(2)) to d(x(2)-y(2))+id(xy) superconductor

The temperature dependencies of specific heat and spin susceptibility of a coupled dx2-y2 + idxy superconductor in the presence of a weak dxy component are investigated in the tight-binding model (1) on square lattice and (2) on a lattice with orthorhombic distortion. As the temperature is lowered past the critical temperature Tc, first a less ordered dx2-y2 superconductor is created, which changes to a more ordered dx2-y2 + idxy superconductor at Tcl(< Tc). This manifests in two second order phase transitions identified by two jumps in specific heat at Tc and Tc1. The temperature dependencies of the superconducting observables exhibit a change from power-law to exponential behavior as temperature is lowered below Tc1 and confirm the new phase transition. © 1998 Published by Elsevier Science B.V. All rights reserved.

Misturador para análise de propriedades reológicas

This study aimed to evaluate the use of a mixer to determine the rheological properties of fluids. The mixer is comprised of an agitation tank and an anchor type impeller. The tests were performed with honey and fruit juices (orange, guava and peach). The rheological characterization was performed using data from the torque and rotation speed required for the operation of fluid agitation. Tests were also made with a concentric cylinder rotational viscometer with the samples being subjected to various shear rates. The rheological parameters were obtained from the flow curves fitted to the power law model. Analyses of results showed that the mixer can be used, within its limitations, to determine rheological properties.