Search results for "TRANSITIONS"
showing 10 items of 251 documents
In-situ high-pressure x-ray diffraction study of zinc ferrite nanoparticles
2016
We have studied the high-pressure structural behavior of zinc ferrite (ZnFe2O4) nanoparticles by powder X-ray diffraction measurements up to 47 GPa. We found that the cubic spinel structure of ZnFe2O4 remains up to 33 GPa and a phase transition is induced beyond this pressure. The high-pressure phase is indexed to an orthorhombic CaMn2O4-type structure. Upon decompression the low- and high-pressure phases coexist. The compressibility of both structures was also investigated. We have observed that the lattice parameters of the high-pressure phase behave anisotropically upon compression. Further, we predict possible phase transition around 55 GPa. For comparison, we also studied the compressi…
Electrocaloric Effect in (1−x)(0.8Na0.5Bi0.5TiO3-0.2BaTiO3)−xCaTiO3 Solid Solutions at High Electric Fields
2022
This research was funded by the Latvian Science Council Fund, grant number lzp-2020/2-0080. The Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme, grant number 739508.
PTPlot: a tool for exploring the gravitational wave power spectrum from first-order phase transitions
2022
PTPlot is a tool for exploring the gravitational wave power spectrum from first-order phase transitions, and evaluating the likelihood of detecting a signal with the LISA mission. The results plotted by this tool are based on the paper Detecting gravitational waves from cosmological phase transitions with LISA: an update, arXiv:1910.13125, which has been published in JCAP. Please cite both that paper, and this Zenodo deposit, if possible. The source for PTPlot is available at https://bitbucket.org/dweir/ptplot.
Introduction to Symposium: Poecilogony--A Window on Larval Evolutionary Transitions in Marine Invertebrates
2012
Poecilogony is the intraspecific variation in developmental mode that has been described in some marine invertebrates. Poecilogonous species produce different larval forms (e.g., free-swimming planktotrophic larvae as well as brooded lecithotrophic or adelphophagic larvae). Poecilogony can be a controversial topic, since it is difficult to identify and characterize the phenomenon with certainty. It has been challenging to determine whether poecilogony represents developmental polymorphism with a genetic basis or developmental polyphenism reflecting plastic responses to environmental cues. Other outstanding questions include whether common mechanisms underlie the developmental variation we o…
Swarming : An Investigation Practice Supporting a Bottom-up Ecological Transition
2022
Dans cet article, nous rendons compte des pratiques d’essaimage d’initiatives locales de transition portées par des collectifs citoyens et associatifs en région Bourgogne Franche-Comté. L’essaimage, défini comme une façon d’enquêter pour agir, caractérise un « activisme environnemental du faire » qui se structure de manière réticulaire et translocale. Ces multiples initiatives qui font des gestes du quotidien un levier de transformation écologique s’activent avec ou sans les institutions territoriales. Celles-ci, indépendamment de l’écho qu’elles renvoient à ces expérimentations, sont interpellées dans leur manière de concevoir l’action publique sous contrainte écologique forte.
Adolescents’ preparedness and motivation across the transition to post-comprehensive education
2017
This longitudinal study aims to test the concept of transition preparedness in the context of educational transitions. The study investigates how adolescents' transition preparedness, conceptualized as their self-efficacy beliefs and their inoculation against setbacks, before an educational transition affect the adolescents' school value and effort related to educational goals after the transition through the effects on achievement goal orientations. Student data from three waves of a longitudinal study are used, first collected in 2004 (before the students' transition from comprehensive school to upper secondary education) and then collected twice after the transition. The students include…
Static Properties of a Simulated Supercooled Polymer Melt: Structure Factors, Monomer Distributions Relative to the Center of Mass, and Triple Correl…
2004
We analyze structural and conformational properties in a simulated bead-spring model of a non-entangled, supercooled polymer melt. We explore the statics of the model via various structure factors, involving not only the monomers, but also the center of mass (CM). We find that the conformation of the chains and the CM-CM structure factor, which is well described by a recently proposed approximation [Krakoviack et al., Europhys. Lett. 58, 53 (2002)], remain essentially unchanged on cooling toward the critical glass transition temperature of mode-coupling theory. Spatial correlations between monomers on different chains, however, depend on temperature, albeit smoothly. This implies that the g…
Hybrid molecular magnets incorporating organic donors and other electroactive molecules
1999
Molecule-based bidimensional ferromagnets can be used as anionic hosts for electroactive molecules, with the aim of obtaining multiproperty materials exhibiting in addition to the cooperative magnetism other interesting properties according to the nature of the inserted molecules. In particular, hybrid molecular compounds containing conducting (TTF-type organic donors), bi-stable or non-linear optical species are reported.
Transcriptomes of parents identify parenting strategies and sexual conflict in a subsocial beetle
2015
This work was funded by UK NERC grants to M.G.R. and A.J.M. an NERC studentship to D.J.P. the University of Georgia and a US NSF grant to A.J.M. and M.G.R. Parenting in the burying beetle Nicrophorus vespilloides is complex and, unusually, the sex and number of parents that can be present is flexible. Such flexibility is expected to involve specialized behaviour by the two sexes under biparental conditions. Here, we show that offspring fare equally well regardless of the sex or number of parents present. Comparing transcriptomes, we find a largely overlapping set of differentially expressed genes in both uniparental and biparental females and in uniparental males including vitellogenin, ass…
Self and N-2 collisional broadening of far-infrared methane lines measured at the SOLEIL synchrotron
2012
International audience; Following our recent study devoted to measurements of intensities of pure rotation lines of methane, room temperature far infrared spectra of methane diluted in nitrogen at five total pressures between 100 and 800 hPa have been recorded at the AILES beamline of the SOLEIL synchrotron. One hundred and five N-2 broadening coefficients of methane pure rotation lines have been measured in the 83-261 cm(-1) spectral range using multi-spectrum non-linear least squares fitting of Voigt profiles. Pressure-induced line shifts were not needed to fit the spectra to the noise level and line mixing effects were neglected. One hundred and seventy-six self broadening coefficients h…