The existence of temporal correlations during the intermittent dynamics of a thermally driven structural phase transition is studied in a Cu-Zn-Al alloy. The sequence of avalanches is observed by means of two techniques: acoustic emission and high sensitivity calorimetry. Both methods reveal the existence of event clustering in a way that is equivalent to the Omori correlations between aftershocks in earthquakes as are commonly used in seismology.

This work analyzes time use surveys from 19 countries (17 European and 2 American) in the middle latitude (38–61 degree) accounting for 45% of world population in this range. Time marks for primary activities are contrasted against light/dark conditions. The analysis reveals winter sunrise synchronizes labor start time below 54 degree, occurring within winter civil twilight. Winter sunset is a source of synchronization for labor end times. Winter terminator punctuate meal times in Europe: dinner occurs 3 h after winter sunset time within 1 h; 40% narrower than variability of dinner local times. The sleep-wake cycle of laborers is shown to be related to winter sunrise whereas standard population’s appears to be irrespective of latitude. The significance of the winter terminator depends on two competing factors average labor time (~7 h30 m) and the shortest photoperiod. Winter terminator gains significance when both roughly matches. That is within a latitude range from 38 degree to 54 degree. The significance of winter terminator as a source of synchronization is also related to contemporary year round time schedules: the shortest photoperiod represents the worst case scenario the society faces.

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Heat treatment induced martensitic accommodation and adaptive anisotropy in melt spun Ni55Mn22Ga23 (at. %) ribbons J. Appl. Phys. 112, 103512 (2012) Modulated structure in the martensite phase of Ni1.8Pt0.2MnGa: A neutron diffraction study Appl. Phys. Lett. 101, 171904 (2012) Martensitic and magnetic transformation in Mn50Ni50−xSnx ferromagnetic shape memory alloys J. Appl. Phys. 112, 083902 (2012) Ellipsometry applied to phase transitions and relaxation phenomena in Ni2MnGa ferromagnetic shape memory alloy Appl.

The asymptotic behaviour near phase transitions can be suitably characterized by the scaling of ∆s/Q 2 with ǫ = 1 − T /T c , where ∆s is the excess entropy and Q is the order parameter. As ∆s is obtained by integration of the experimental excess specific heat of the transition ∆c, it displays little experimental noise so that the curve log(∆s/Q 2 ) versus log ǫ is better constrained than, say, log ∆c versus log ǫ. The behaviour of ∆s/Q 2 for different universality classes is presented and compared. In all cases, it clearly deviates from being a constant. The determination of this function can then be an effective method to distinguish asymptotic critical behaviour. For comparison, experimental data for three very different systems, Rb 2 CoF 4 , Rb 2 ZnCl 4 and SrTiO 3 , are analysed under this approach. In SrTiO 3 , the function ∆s/Q 2 does not deviate within experimental resolution from a straight line so that, although Q can be fitted with a non mean-field exponent, the data can be explained by a classical Landau mean-field behaviour. In contrast, the behaviour of ∆s/Q 2 for the antiferromagnetic transition in Rb 2 CoF 4 and the normal-incommensurate phase transition in Rb 2 ZnCl 4 is fully consistent with the asymptotic critical behaviour of the universality class corresponding to each case. This analysis supports, therefore, the claim that incommensurate phase transitions in general, and the A 2 BX 4 compounds in particular, in contrast with most structural phase transitions, have critical regions large enough to be observable.