Concept

Manteau terrestre

Publications associées (105)

Primordial metallic melt in the deep mantle

Seismic tomography models reveal two large low shear velocity provinces (LLSVPs) that identify large-scale variations in temperature and composition in the deep mantle. Other characteristics include elevated density, elevated bulk sound speed, and sharp bo ...

Amer Geophysical Union2016

An early geodynamo driven by exsolution of mantle components from Earth's core

James Badro

Recent palaeomagnetic observations(1) report the existence of a magnetic field on Earth that is at least 3.45 billion years old. Compositional buoyancy caused by inner-core growth(2) is the primary driver of Earth's present-day geodynamo(3-5), but the inne ...

Nature Publishing Group2016

Phase transition processes of olivine in the shocked Martian meteorite Tissint: Clues to origin of ringwoodite-, bridgmanite- and magnesiowilstite-bearing assemblages

Philippe Gillet

Tissint is a heavily shocked olivine-phyric shergottite. We investigated and documented several phase transformations and dissociation phenomena of olivine adjacent to and in many shock-induced melt-pockets of Tissint. Olivine grains entrained in the melt- ...

Elsevier2016

Detection and characterization of the melting layer based on polarimetric radar scans

Alexis Berne, Daniel Wolfensberger, Danny Eddy Scipion Castillo

Stratiform rain situations are generally associated with the presence of a melting layer characterized by a strong signature in polarimetric radar variables. This layer is an important feature as it indicates the transition from solid to liquid precipitati ...

Wiley-Blackwell2016

Enhanced Charge Collection with Passivation Layers in Perovskite Solar Cells

Mohammad Khaja Nazeeruddin, Shaik Mohammed Zakeeruddin, Peng Gao, Jingshan Luo, Yonghui Lee, Kyung Taek Cho, Jiyoun Seo, Minkyu Son

The Al2O3 passivation layer is beneficial for mesoporous TiO2-based perovskite solar cells when it is deposited selectively on the compact TiO2 surface. Such a passivation layer suppressing surface recombination can be formed by thermal decomposition of th ...

Wiley-V C H Verlag Gmbh2016

Enhancing Efficiency of Perovskite Solar Cells via N-doped Graphene: Crystal Modification and Surface Passivation

Shaik Mohammed Zakeeruddin, Ulf Anders Hagfeldt, Michael Saliba, Jingshan Luo, Antonio Abate, Juan-Pablo Correa-Baena, Jiyoun Seo, Amita Ummadisingu, Mahboobeh Hadadian

Controlling the morphology and surface passivation in perovskite solar cells is paramount in obtaining optimal opto-electronic properties. This study incorporates N-doped graphene nanosheets in the perovskite layer, which simultaneously induces an improved ...

2016

Carbon nanotube-based hybrid hole-transporting material and selective contact for high efficiency perovskite solar cells

Michael Graetzel, Ulf Anders Hagfeldt, Antonio Abate, Juan-Pablo Correa-Baena

We demonstrate a high efficiency perovskite solar cell with a hybrid hole-transporting material-counter electrode based on a thin single-walled carbon nanotube (SWCNT) film and a drop-cast 2,2,7,-7-tetrakis(N, N-di-p-methoxyphenylamine)-9,90-spirobifluoren ...

Royal Soc Chemistry2016

Spin state transition and partitioning of iron: Effects on mantle dynamics

James Badro

Experimental studies at pressure and temperature conditions of the Earth's lower mantle have shown that iron in ferropericlase (Fp) and in Mg-silicate perovskite (Pv) undergoes a spin state transition. This electronic transition changes elastic and transpo ...

Elsevier2015

Composition dependence of spin transition in (Mg,Fe)SiO3 bridgmanite

Philippe Gillet, James Badro, Susannah McGregor Dorfman

Spin transitions in (Mg,Fe)SiO3 bridgmanite have important implications for the chemistry and dynamics of Earth's lower mantle, but have been complex to characterize in experiments. We examine the spin state of Fe in highly Fe-enriched bridgmanite synthesi ...

Mineralogical Society of America2015

Core formation and core composition from coupled geochemical and geophysical constraints

James Badro, Hélène Marie Piet

The formation of Earth's core left behind geophysical and geochemical signatures in both the core and mantle that remain to this day. Seismology requires that the core be lighter than pure iron and therefore must contain light elements, and the geochemistr ...

Natl Acad Sciences2015

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