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Concept

Protoxyde d'azote

Publications associées (29)

The simultaneous Selective Catalytic Reduction of N2O and NO over Fe-exchanged zeolites

Filippo Buttignol

Iron-exchanged zeolites are industrial heterogeneous catalysts deployed to remediate anthropogenic emissions of both nitrous oxide (N2O) and nitrogen oxides (NOx = NO + NO2). Despite the extensive scientific attention received, limited knowledge is availab ...

EPFL2024

Atmospheric isoprene measurements reveal larger-than-expected Southern Ocean emissions

Julia Schmale, Andrea Baccarini

Isoprene is a key trace component of the atmosphere emitted by vegetation and other organisms. It is highly reactive and can impact atmospheric composition and climate by affecting the greenhouse gases ozone and methane and secondary organic aerosol format ...

Nature Research2024

Homogeneous catalysis with nitrous oxide

Kay Severin

Nitrous oxide (N2O; ‘laughing gas’) is a powerful oxidant, but chemical transformations are hampered by the inert character of this gas. Recent advances in using N2O as an oxidant in metal-catalyzed reactions are discussed. The focus will be on reactions t ...

2023

Metabolic Performance and Fate of Electrons during Nitrate-Reducing Fe(II) Oxidation by the Autotrophic Enrichment Culture KS Grown at Different Initial Fe/N Ratios

Natalia Jakus

Autotrophic nitrate-reducing Fe(II)-oxidizing (NRFeOx) microorganisms fix CO2 and oxidize Fe(II) coupled to denitrification, influencing carbon, iron, and nitrogen cycles in pH-neutral, anoxic environments. However, the distribution of electrons from Fe(II ...

AMER SOC MICROBIOLOGY2023

Size-resolved inhalation intake fractions for particles released from human activities in residential indoor environments

Dusan Licina, Marouane Merizak

Inhalation exposure to elevated concentrations of airborne particulate matter is a public health concern. Assessment of exposure can be enhanced through better knowledge of source-receptor relationships, which can be characterized through the inhalation in ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Nitrogen oxides in the free troposphere: implications for tropospheric oxidants and the interpretation of satellite NO2 measurements

Ilann Ernest Valentin Bourgeois

Satellite-based retrievals of tropospheric NO(2)columns are widely used to infer NOx (equivalent to NO + NO2) emissions. These retrievals rely on model information for the vertical distribution of NO2. The free tropospheric background above 2 km is particu ...

Copernicus GmbH2023

Synthetic chemistry with nitrous oxide and triazenes

Iris Roswitha Landman

Nitrous oxide (N2O) has gained much interest because of its physiological effects ("laughing gas") and its negative environmental impact ("greenhouse gas", "ozone-depleting substance"): It has a lifetime of more than 100 years in the atmosphere. Its persis ...

EPFL2022

Unexpectedly minor nitrous oxide emissions from fluvial networks draining permafrost catchments of the East Qinghai-Tibet Plateau

Tom Ian Battin

Streams and rivers emit substantial amounts of nitrous oxide (N2O) and are therefore an essential component of global nitrogen (N) cycle. Permafrost soils store a large reservoir of dormant N that, upon thawing, can enter fluvial networks and partly degrad ...

Nature Research2022

Isolation, Characterisation and Reactivity of N-Heterocyclic Diazoolefins

Paul Varava

Examples for applications of nitrous oxide in organic synthesis remain rare up until today. First mayor contributions of our group were published in 2012, when nitrous oxide was successfully captured by N-heterocyclic carbenes. Subsequent studies investiga ...

EPFL2022

Nitrous oxide as a diazo transfer reagent: the synthesis of triazolopyridines

Kay Severin, Farzaneh Fadaei Tirani, Iris Roswitha Landman

Nitrous oxide is a potential diazo transfer reagent, but its applications in organic chemistry are scarce. Here, we show that triazolopyridines and triazoloquinolines are formed in the reactions of metallated 2-alkylpyridines or 2-alkylquinolines with N2O. ...

Royal Society of Chemistry2021

Ozone Initiates Human-Derived Emission of Nanocluster Aerosols

Dusan Licina, Shen Yang

Nanocluster aerosols (NCAs, particles

AMER CHEMICAL SOC2021

Isolation and characterization of diazoolefins

Rosario Scopelliti, Kay Severin, Farzaneh Fadaei Tirani, Zhaowen Dong, Paul Varava

Diazoolefins tend to be highly reactive compounds that rapidly lose dinitrogen. So far, most experimental evidence for diazoolefins is indirect, via trapping experiments. Here we show that diazoolefins are observed to form in reactions of N-heterocyclic ol ...

2021

Historical Changes in Seasonal Aerosol Acidity in the Po Valley (Italy) as Inferred from Fog Water and Aerosol Measurements

Athanasios Nenes

Acidity profoundly affects almost every aspect that shapes the composition of ambient particles and their environmental impact. Thermodynamic analysis of gas-particle composition datasets offers robust estimates of acidity, but they are not available for l ...

AMER CHEMICAL SOC2021

N2O Decomposition over Fe-ZSM-5: A Systematic Study in the Generation of Active Sites

Lioubov Kiwi, Bryan Bromley

We have carried out a systematic investigation of the critical activation parameters (i.e., final temperature (673-1273 K), atmosphere (He vs. O-2/He), and final isothermal hold (1 min-15 h) on the generation of "alpha-sites", responsible for the direct N2 ...

2020

Evaluation of Total Reactive Oxide Ratios and Working Solution Ratios on Strength Development in Fly Ash-Based Geopolymers

Venkata Prasanna Bhagath Singh Gangapatnam

Fly ash-based geopolymers are being developed as sustainable alternate binders for producing concrete. The consistent production of a stable geopolymeric binder suitable for use in structural applications from alkaline activation of low-calcium fly ash was ...

2020

Pencil Graphite Needle-Shaped Biosensor for Anaesthetic Monitoring in Human Serum

Sandro Carrara, Danilo Demarchi, Simone Aiassa

Direct and online continuous monitoring of anaesthetic intake by the patient's blood stream improves practices in the critical procedure of anaesthesia. Several systems have been proposed to address this challenge. Electrochemical techniques are highly app ...

IEEE2020

Enhanced transformation of sulfonamide antibiotics by manganese(IV) oxide in the presence of model humic constituents

Urs von Gunten, Jun Ma, Jin Jiang

In this study, a manganese(IV) oxide-mediator (MnO2-mediator) system for the abatement of sulfonamide antibiotics was evaluated. Two simple model humic constituents, syringaldehyde (SA) and acetosyringone (AS), could promote the transformation of sulfonami ...

PERGAMON-ELSEVIER SCIENCE LTD2019

Response of N2O production rate to ocean acidification in the western North Pacific

Florian Frédéric Vincent Breider

Ocean acidification, induced by the increase in anthropogenic CO2 emissions, has a profound impact on marine organisms and biogeochemical processes1. The response of marine microbial activities to ocean acidification might play a crucial role in the future ...

Nature Publishing Group2019

Synthesis of Organic Super-Electron-Donors by Reaction of Nitrous Oxide with N-Heterocyclic Olefins

Rosario Scopelliti, Kay Severin, Farzaneh Fadaei Tirani, Andrzej Sienkiewicz, Basile Curchod, Léonard Yannick Maurice Eymann, Paul Varava, Ophélie Marie Planes, Yizhu Liu

The reaction of nitrous oxide (N2O) with N-heterocyclic olefins (NHOs) results in cleavage of the N–O bond and formation of azo-bridged NHO dimers. The latter represent very electron-rich compounds with a low ionization energy. Cyclic voltammetry studies s ...

2019

Effects of Atmospheric Processing on the Oxidative Potential of Biomass Burning Organic Aerosols

Athanasios Nenes, Kalliopi Violaki

Oxidative potential (OP), which is the ability of certain components in atmospheric particles to generate reactive oxidative species (ROS) and deplete antioxidants in vivo, is a prevailing toxicological mechanism underlying the adverse health effects assoc ...

AMER CHEMICAL SOC2019