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Publications associées (14)

Aerosol and dynamical contributions to cloud droplet formation in Arctic low-level clouds

Athanasios Nenes, Ghislain Gilles Jean-Michel Motos, Paraskevi Georgakaki, Jörg Wieder, Guangyu Li

The Arctic is one of the most rapidly warming regions of the globe. Low-level clouds and fog modify the energy transfer from and to space and play a key role in the observed strong Arctic surface warming, a phenomenon commonly termed "Arctic amplification" ...

Gottingen2023

Evidence of extensive lunar crust formation in impact melt sheets 4,330 Myr ago

Cyril Cayron

Accurately constraining the formation and evolution of the lunar magnesian suite is key to understanding the earliest periods of magmatic crustal building that followed accretion and primordial differentiation of the Moon. However, the origin and evolution ...

2020

Biogenic non-crystalline U(IV) revealed as major component in uranium ore deposits

Rizlan Bernier-Latmani

Historically, it is believed that crystalline uraninite, produced via the abiotic reduction of hexavalent uranium (U-(VI)) is the dominant reduced U species formed in low-temperature uranium roll-front ore deposits. Here we show that non-crystalline U-(IV) ...

Nature Publishing Group2017

Loss of testate amoeba functional diversity with increasing frost intensity across a continental gradient reduces microbial activity in peatlands

Alexandre Buttler, Luca Bragazza, Vincent Eric Jules Jassey, Mariusz Lamentowicz, Constant Signarbieux, Bjorn Jozef Maria Robroek, Robert Thomas Edmund Mills, Maaike Louise Hofsommer

Soil microbial communities significantly contribute to global fluxes of nutrients and carbon. Their response to climate change, including winter warming, is expected to modify these processes through direct effects on microbial functions due to osmotic str ...

Elsevier2016

Copper isotope evidence for large-scale sulphide fractionation during Earth’s differentiation

James Badro

The differentiation of Earth into a metallic core and silicate mantle left its signature on the chemical and isotopic composition of the bulk silicate Earth (BSE). This is seen in the depletion of siderophile (metal-loving) relative to lithophile (rock-lov ...

2015

Crustal differentiation in the early solar system: Clues from the unique achondrite Northwest Africa 7325 (NWA 7325)

Philippe Gillet

The unique achondrite NWA 7325 is an unusual olivine gabbro composed chiefly of calcic plagioclase (An(85-93)), diopsidic pyroxene (En(50.1-54.0) Wo(44.8-49.3) Fs(0.6-1.3)), and forsteritic olivine (Fo(97)). It is Al and Mg-rich and Fe and Na-poor and disp ...

Pergamon-Elsevier Science Ltd2015

Observations of continental biogenic impacts on marine aerosol and clouds off the coast of California

Athanasios Nenes, Zheng Wang

During the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE) and 2013 Nucleation in California Experiment (NiCE) field campaigns, a predominantly organic aerosol (> 85% by mass) was observed in the free troposphere over marine stratocumulus o ...

Wiley-Blackwell2014

Relative Reactivity of Biogenic and Chemogenic Uraninite and Biogenic Non-Crystalline U(IV)

Rizlan Bernier-Latmani

Aqueous chemical extractions and X-ray absorption spectroscopy (XAS) analyses were conducted to investigate the reactivity of chemogenic uraninite, nanoparticulate biogenic uraninite, and biogenic monomeric U(IV) species. The analyses were conducted in sys ...

2013

Electrical conductivity in a partially molten crust from measurements on metasedimentary enclaves

Marie Estelle Solange Violay

The complex electrical impedance of a garnet-biotite-sillimanite residual enclave in the Neogene dacite of El Hoyazo (SE Spain) has been determined up to 978. °C at 200-300. MPa. This well studied material represents a direct sampling of the Alborán Domain ...

2013

Diversity in the Archean Biosphere: New Insights from NanoSIMS

Anders Meibom, François Robert

The origin of organic microstructures in the similar to 3 Ga Farrel Quartzite is controversial due to their relatively poor state of preservation, the Archean age of the cherts in which they occur, and the unusual spindle-like morphology of some of the for ...

2010

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