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

Oxidation processes and me

This publication summarizes my journey in the field of chemical oxidation processes for water treatment over the last 30+ years. Initially, the efficiency of the application of chemical oxidants for micropollutant abatement was assessed by the abatement of ...

Pergamon-Elsevier Science Ltd2024

The Mn(VII)-H2O2 oxidation process: Abatement of electron-deficient N-containing organic compounds

Urs von Gunten, Ke Xu

Chemical oxidants applied in water treatment are electrophiles, which preferentially attack sites with higher electron density. This typically results in less efficient oxidative abatement of organic compounds with electronwithdrawing substituents. In this ...

Elsevier Science Sa2024

Reactivity of Cyanobacteria Metabolites with Ozone: Multicompound Competition Kinetics

Urs von Gunten

Cyanobacterial blooms occur at increasing frequency and intensity, notably in freshwater. This leads to the introduction of complex mixtures of their products, i.e., cyano-metabolites, to drinking water treatment plants. To assess the fate of cyano-metabol ...

Amer Chemical Soc2024

New Applications of 1,3,2-Diazaphospholenes in Catalysis

Johannes Klett

The constant urge to construct new molecules in an economical and sustainable fashion led to the development of numerous metal-catalyzed transformations. Organocatalysts consisting of abundant and more sustainable elements offer an elegant solution to over ...

EPFL2024

Charge-Transfer States in Organic Nanowires

Lucile Annie Chassat

Charge separation processes in organic semiconductors play a pivotal role in diverse applications ranging from photovoltaics to photocatalysis. Understanding these mechanisms, particularly the role of hybrid charge-transfer (CT) states, is essential for ad ...

EPFL2024

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

Dusan Licina, Shen Yang

Nanocluster aerosols (NCA, particles

Pergamon-Elsevier Science Ltd2024

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

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

Treeline displacement may affect lake dissolved organic matter processing at high latitudes and altitudes

Hannes Markus Peter

Climate change induced shifts in treeline position, both towards higher altitudes and latitudes induce changes in soil organic matter. Eventually, soil organic matter is transported to alpine and subarctic lakes with yet unknown consequences for dissolved ...

Nature Portfolio2024

In Situ Synthesis of CuxO/N Doped Graphdiyne with Pyridine N Configuration for Ammonia Production via Nitrate Reduction

Sophia Haussener, Roberto Valenza, Jian Li

Electroreduction of nitrate to ammonia provides an interesting pathway for wastewater treatment and valorization. Cu-based catalysts are active for the conversion of NO3− to NO2− but suffer from an inefficient hydrogenation process of NO2−. Herein, CuxO/N- ...

2024

Optimal regimes for algorithm-assisted human decision-making

Mats Julius Stensrud, Aaron Leor Sarvet

We consider optimal regimes for algorithm-assisted human decision-making. Such regimes are decision functions of measured pre-treatment variables and, by leveraging natural treatment values, enjoy a superoptimality property whereby they are guaranteed to o ...

2024

Photo-Fenton inactivation of MS2 bacteriophage at alkaline pH by Fe salts or nm to μm-sized oxides, and the Janus-faced effects of natural organic matter in surface waters

César Pulgarin, Stefanos Giannakis, Ogadimma Cassandra Oji-Okoro, Giulio Farinelli

In this study, MS2 bacteriophage was inactivated by homogeneous and heterogeneous photo-Fenton processes in an alkaline matrix (pH 8) using low concentrations of H2O2 and iron forms (1 mg/L), including Fe(II), Fe(III), and Fe (hydr)oxides. As a reference, ...

Elsevier2024

Novel Alkynylation Methods through the Combination of Hypervalent Iodine Reagents and Alkynyl-trifluoroborate Salts

Julien Aymeric Borrel

The alkyne motif is a versatile functional group often encountered in organic chemistry. It can be involved in various transformations such as the alkyne-azide cycloaddition and has found widespread application in medicinal chemistry, chemical biology and ...

EPFL2024

Microbial genome collection of aerobic granular sludge cultivated in sequencing batch reactors using different carbon source mixtures

Aline Sondra Adler, Christof Holliger, Pilar Natalia Rodilla Ramírez, Laetitia Janine Andrée Cardona, Jaspreet Singh Saini, Ruizhe Pei

Aerobic granular sludge (AGS) consists of a microbial consortium that has an important role in wastewater treatment. This study investigates AGS microorganisms cultivated in a laboratory-scale sequencing batch reactor. Metagenomic sequencing was conducted ...

Amer Soc Microbiology2024

Monitoring an Emergent Pathogen at Low Incidence in Wastewater Using qPCR: Mpox in Switzerland

Tamar Kohn, Timothy R. Julian

Wastewater-based epidemiology offers a complementary approach to clinical case-based surveillance of emergent diseases and can help identify regions with infected people to prioritize clinical surveillance strategies. However, tracking emergent diseases in ...

2024

MRI characterization of in vitro clots at 3T and 7T: A technical note

François Lazeyras, Lijing Xin

In acute ischemic stroke, the composition of the occlusive clot can be associated with the underlying pathophysiology and the response to treatment. For these reasons, it is important to characterize the clot composition from clinical scans. We examine the ...

Masson Editeur2024

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

Oxidative Water Treatment: The Track Ahead

Urs von Gunten, Yun Ho Lee

Chemical oxidation has been applied in municipal water treatment for more than a century, initially for disinfection. In the early decades, chlorine disinfection was adopted in the fight against waterborne disease. However, the oxidative properties of chlo ...

2023