Correlation between electric-field-induced phase transition and piezoelectricity in lead zirconate titanate films

We observed that electric field induces phase transition from tetragonal to rhombohedral in polycrystalline morphotropic lead zirconate titanate (PZT) films, as reported in 2011 for bulk PZT. Moreover, we evidenced that this field-induced phase transition is strongly correlated with PZT film piezoelectric properties, that is to say the larger the phase transition, the larger the longitudinal piezoelectric coefficient d 33,eff . Although d 33,eff is already comprised between as 150 to 170 pm/V, our observation suggests that one could obtain larger d 33,eff values, namely 250 pm/V, by optimizing the field-induced phase transition thanks to composition fine tuning

A new landscape for systemic pharmacotherapy of recurrent glioblastoma?

Glioblastoma is the most common and aggressive primary malignant brain tumor in adult patients [...

Ru Clusters Synthesized Chemically from Dissolved Carbonyl: In Situ Study of a Novel Electrocatalyst in the Gas Phase and in Electrochemical Environment

Highly dispersed nanocrystalline Ru particles were prepared under mild conditions in organic solvents such as xylene (Xyl) or dichlorobenzene (Dcb) from the Ru carbonyl precursor. The route of this chemical synthesis determines the physicochemical properties of these materials. This phenomenon is clearly shown in the voltammetric current−potential characteristics of Rux(Xyl) and Rux(Dcb). Although both materials have a similar particle size, in the reduced state, Rux(Xyl) shows a higher electrochemical pseudocapacitance than Rux(Dcb) by a factor of 10. However, in ambient conditions, the particles slowly oxidize to an amorphous RuxOy species. Their interfacial behavior is similar. Both species and their differences have been characterized by in situ X-ray diffraction. Samples prepared in xylene, RuxOy(Xyl), can be partly reduced in 1 bar of hydrogen at room temperature to ∼2 nm size hcp ruthenium and grown to ∼8 nm particles at 200 °C. In contrast, samples prepared in dichlorobenzene, RuxOy(Dcb), under the same conditions can only be reduced at 140 °C, to form perfect 2 nm hcp ruthenium clusters of narrow size distribution. This sample is reversibly reoxidized to the amorphous RuxOy species at 200 °C in oxygen. The large 8 nm Ru particles based on the xylene preparation are, however, stable under these conditions. The driving force for such a difference in the electrochemical behavior lies on the disorder precursor state of nano-ruthenium

Molecular identification of the four European Trichinella species by amplification of the Small and Large Subunit Ribosomal mitochondrial RNA genes

International audienc

Does Ixodes ricinus transmit Bartonella henselae ?

International audienc

Molecular identification of the four European Trichinella species by amplification of the Small and Large Subunit Ribosomal mitochondrial RNA genes

International audienc