Mediaspace scheduled maintenance: Aug 25, 2026 07:00 - 12:00 AM. During this time, videos will be temporarily unavailable. Check status updates.

Concept

Cycle ozone-oxygène

Publications associées (30)

Nanocluster aerosol formation via ozone chemistry on worn clothing: Influence of environmental parameters

Dusan Licina, Shen Yang

Nanocluster aerosols (NCA, particles

Pergamon-Elsevier Science Ltd2024

Influence of Ventilation on Formation and Growth of 1-20 nm Particles via Ozone-Human Chemistry

Dusan Licina, Shen Yang, Marouane Merizak, Meixia Zhang

Ozone reaction with human surfaces is an important source of ultrafine particles indoors. However, 1-20 nm particles generated from ozone-human chemistry, which mark the first step of particle formation and growth, remain understudied. Ventilation and indo ...

Amer Chemical Soc2024

Nanocluster Aerosols from Ozone-Human Chemistry Are Dominated by Squalene-Ozone Reactions

Dusan Licina, Shen Yang

Nanocluster aerosols (NCAs,

Amer Chemical Soc2024

Squalene Depletion in Skin Following Human Exposure to Ozone under Controlled Chamber Conditions

Shen Yang

A major component of human skin oil is squalene, a highly unsaturated hydrocarbon that protects the skin from atmospheric oxidants. Skin oil, and thus squalene, is continuously replenished on the skin surface. Squalene is also quickly consumed through reac ...

Amer Chemical Soc2024

Critical Review on Bromate Formation during Ozonation and Control Options for Its Minimization

Urs von Gunten

Ozone is a commonly applied disinfectant and oxidantin drinkingwater and has more recently been implemented for enhanced municipalwastewater treatment for potable reuse and ecosystem protection. Onedrawback is the potential formation of bromate, a possible ...

AMER CHEMICAL SOC2023

Modelling the coupled mercury-halogen-ozone cycle in the central Arctic during spring

Julia Schmale, Ivo Fabio Beck, Hélène Paule Angot

Near-surface mercury and ozone depletion events occur in the lowest part of the atmosphere during Arctic spring. Mercury depletion is the first step in a process that transforms long-lived elemental mercury to more reactive forms within the Arctic that are ...

2023

Evaluation of the role of superoxide radical as chain carrier for the formation of hydroxyl radical during ozonation

Urs von Gunten, Gang Yu

Superoxide radicals (O-2(center dot-)) have been suggested as an important chain carrier in the radical chain reaction that promotes ozone (O-3) decomposition to hydroxyl radicals ((OH)-O-center dot) during ozonation. However, due to the difficulty in meas ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Arctic tropospheric ozone: assessment of current knowledge and model performance

Jakob Boyd Pernov, Luca Pozzoli, Ilann Ernest Valentin Bourgeois

As the third most important greenhouse gas (GHG) after carbon dioxide (CO2) and methane (CH4), tropospheric ozone (O3) is also an air pollutant causing damage to human health and ecosystems. This study brings together recent research on observations and mo ...

Copernicus Publications2023

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

Widespread detection of chlorine oxyacids in the Arctic atmosphere

Julia Schmale, Ivo Fabio Beck, Hélène Paule Angot

Observations are reported of HClO3 and HClO4 in the atmosphere and their widespread occurrence over the pan-Arctic during spring, providing further insights into atmospheric chlorine cycling in the polar environment. ...

Nature Portfolio2023

Ozonation of organic compounds in water and wastewater: A critical review

Urs von Gunten, Sung Eun Lim

Ozonation has been applied in water treatment for more than a century, first for disinfection, later for oxidation of inorganic and organic pollutants. In recent years, ozone has been increasingly applied for enhanced municipal wastewater treatment for eco ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Optical properties and photochemical production of hydroxyl radical and singlet oxygen after ozonation of dissolved organic matter

Urs von Gunten, Frank Jonathan Leresche

This study focuses on the effects of ozonation on the optical and photochemical properties of dissolved organic matter (DOM). Upon ozonation, a decrease in light absorption properties of DOM was observed concomitantly with a large increase in singlet oxyge ...

ROYAL SOC CHEMISTRY2021

Ozone Initiates Human-Derived Emission of Nanocluster Aerosols

Dusan Licina, Shen Yang

Nanocluster aerosols (NCAs, particles

AMER CHEMICAL SOC2021

Molecular-Level Transformation of Dissolved Organic Matter during Oxidation by Ozone and Hydroxyl Radical

Urs von Gunten

Ozonation of drinking and wastewater relies on ozone (O-3) and hydroxyl radical ((OH)-O-center dot) as oxidants. Both oxidants react with dissolved organic matter (DOM) and alter its composition, but the selectivity of the two oxidants and mechanisms of re ...

AMER CHEMICAL SOC2020

Ozone concentration measured during the Arctic Ocean 2018 expedition

Julia Schmale, Andrea Baccarini

Ozone was measured with a 2B Technology ozone monitor (model 205). The concentration is reported as a mixing ratio in parts per billion [ppb], at 60 seconds average. Ozone is a trace gas that can be formed directly in the troposphere (the most important fo ...

2020

Reactions of nitrogen-containing compounds with ozone: kinetics and mechanisms

Sung Eun Lim

Nitrogen-containing moieties are widespread in natural waters in dissolved organic nitrogen and micropollu-tants. They are often susceptible to an electrophilic attack of ozone because of the electron-rich nature of the neutral form of nitrogen in organic ...

EPFL2020

Indoor air treatment of refrigerated food chambers with synergetic association between cold plasma and photocatalysis: Process performance and photocatalytic poisoning

Sami Rtimi

The purpose of this study is to evaluate the efficiency of non-thermal plasma (NTP) and heterogeneous photocatalytic processes for indoor air treatment of refrigerated food chambers. Propionic acid and benzene were chosen as target pollutants to simulate o ...

ELSEVIER SCIENCE SA2020

Temporal and spatial analysis of ozone concentrations in Europe based on timescale decomposition and a multi-clustering approach

Satoshi Takahama, Eirini Boleti

Air quality measures that were implemented in Europe in the 1990s resulted in reductions of ozone precursor concentrations. In this study, the effect of these reductions on ozone is investigated by analyzing surface measurements of this pollutant for the t ...

Copernicus Publications2020

Statistical methods for accounting and understanding ozone trends derived from observations

Eirini Boleti

Emissions of ozone precursors have been regulated in Europe since around 1990 with air quality control measures, which resulted in reductions of nitrogen oxides and volatile organic compounds concentrations. In order to understand how these measures have a ...

EPFL2020

Ultraviolet Photodissociation of Peptides: New Insight on the Mobile Proton Model

Oleg Boyarkine, Aleksandr Pereverzev

In this work, we study the mechanism of peptide photodissociation by ultraviolet irradiation at 193 nm wavelength and discuss the role of ionization proton in this process. We found that substituting the ionization proton for the alkali metal cations (sodi ...

PLEIADES PUBLISHING INC2020