Publications associées à Umpolung of 1-alkoxy-3-acyloxy-1,3-dienes with sulfur dioxide and its application in polypropionate synthesis

Iodine oxoacids enhance nucleation of sulfuric acid particles in the atmosphere

Andrea Baccarini, Lubna Dada, André Welti, Houssni Lamkaddam, Imad El Haddad, Mihnea Surdu

The main nucleating vapor in the atmosphere is thought to be sulfuric acid (H2SO4), stabilized by ammonia (NH3). However, in marine and polar regions, NH3 is generally low, and H2SO4 is frequently found together with iodine oxoacids [HIOx, i.e., iodic acid ...

American Association for the Advancement of Science2023

Genomic insights into the coupling of a Chlorella-like microeukaryote and sulfur bacteria in the chemocline of permanently stratified Lake Cadagno

Christel Sybille Hassler

Meromictic Lake Cadagno is a permanently stratified system with a persistent microbial bloom within the oxic-anoxic boundary called the chemocline. The association between oxygenic and anoxygenic photosynthesis within the chemocline has been known for at l ...

SPRINGERNATURE2023

Poisoning Effects of Cerium Oxide (CeO2) on the Performance of Proton Exchange Membrane Fuel Cells (PEMFCs)

Jan Van Herle, Hossein Pourrahmani

In this study, the poisoning effects of cerium oxide (CeO2) as the contaminant on the performance of proton exchange membrane fuel cells (PEMFCs) are evaluated. An experimental setup was developed to analyze the performance characteristic (I-V) curves in c ...

MDPI2022

Active anaerobic methane oxidation and sulfur disproportionation in the deep terrestrial subsurface

Rizlan Bernier-Latmani, Manon Frutschi, Emma Bell, Chen Qian

Microbial life is widespread in the terrestrial subsurface and present down to several kilometers depth, but the energy sources that fuel metabolism in deep oligotrophic and anoxic environments remain unclear. In the deep crystalline bedrock of the Fennosc ...

2022

Investigation of new particle formation mechanisms and aerosol processes at Marambio Station, Antarctic Peninsula

Lubna Dada

Understanding chemical processes leading to the formation of atmospheric aerosol particles is crucial to improve our capabilities in predicting the future climate. However, those mechanisms are still inadequately characterized, especially in polar regions. ...

Copernicus GmbH2022

An evaluation of new particle formation events in Helsinki during a Baltic Sea cyanobacterial summer bloom

Marjan Marbouti, Lubna Dada

Several studies have investigated new particle formation (NPF) events from various sites ranging from pristine locations, including forest sites, to urban areas. However, there is still a dearth of studies investigating NPF processes and subsequent aerosol ...

Copernicus GmbH2022

Low‐Volatility Vapors and New Particle Formation Over the Southern Ocean During the Antarctic Circumnavigation Expedition

Robin Lewis Modini, Julia Schmale, Andrea Baccarini

During summer, the Southern Ocean is largely unaffected by anthropogenic emissions, which makes this region an ideal place to investigate marine natural aerosol sources and processes. A better understanding of natural aerosol is key to constrain the preind ...

2021

Evaluation of materials for iodine and technetium immobilization through sorption and redox-driven processes

Daniel Teav Sun, Wendy Lee Queen

Radioactive iodine-129 (I-129) and technetium-99 (Tc-9(9)) pose a risk to groundwater due to their long half-lives, toxicity, and high environmental mobility. Based on literature reviewed in Moore et al. (2019) and Pearce et aL (2019), natural and engineer ...

ELSEVIER2020

Active sulfur cycling in the terrestrial deep subsurface

Rizlan Bernier-Latmani, Manon Frutschi, Emma Bell, Chen Qian

The deep terrestrial subsurface remains an environment where there is limited understanding of the extant microbial metabolisms. At Olkiluoto, Finland, a deep geological repository is under construction for the final storage of spent nuclear fuel. It is th ...

2020

Iodic acid, sulfuric acid and methanesulfonic acid collected during the Arctic Ocean 2018 expedition

Julia Schmale, Andrea Baccarini

Measurements of iodic acid, sulfuric acid and methanesulfonic acid concentration in the gas phase obtained with a nitrate chemical ionization mass spectrometer (we used an APi-TOF mass spectrometer produced by Tofwerk AG coupled with a Chemical ionization ...

2020

Frequent new particle formation over the high Arctic pack ice by enhanced iodine emissions

Julia Schmale, Andrea Baccarini

In the central Arctic Ocean the formation of clouds and their properties are sensitive to the availability of cloud condensation nuclei (CCN). The vapors responsible for new particle formation (NPF), potentially leading to CCN, have remained unidentified s ...

Nature Research2020

Sulfuric acid condensation sink calculated for the Arctic Ocean 2018 expedition

Julia Schmale, Andrea Baccarini

The condensation sink is a measure of the sulfuric acid lifetime against condensation on preexisting aerosol particles. Dimensionally it is the inverse of a time (reported in per second) and it is calculated starting from the aerosol size distribution. A l ...

2020

Tribocorrosion of a CoCrMo alloy in sulfuric acid - Glycerol mixtures

Stefano Mischler, Shoufan Cao

This work reports on the tribocorrosion properties of a CoCrMo alloy sliding under imposed passive potential against alumina in sulfuric acid-glycerol mixtures exhibiting different viscosities and thus, in principle, lubrication properties. As expected, we ...

ELSEVIER SCIENCE SA2020

Ultrafine particle concentration measured during the Arctic Ocean 2018 expedition

Julia Schmale, Andrea Baccarini

The ultrafine particle (UFP) concentration is the concentration of particles having a diameter between 2.5 and 15 nm, it is reported in terms of particle number per cubic centimeter at a time resolution of 10 minutes. UFP are the smallest particles within ...

2020

Optimization of Lignin Extraction from Pine Wood for Fast Pyrolysis by Using γ-valerolactone-Based Binary Solvent System

Jeremy Luterbacher, Allen Puente-Urbina

Fast pyrolysis of lignin is a promising method to produce aromatic chemicals and fuels. Lignin structure and pyrolysis conditions determine the liquid yield and product selectivity. Extraction of pine wood using γ-valerolactone (GVL) mixed with water in th ...

2019

Hypobromous Acid as an Unaccounted Sink for Marine Dimethyl Sulfide?

Boris Droz, Urs von Gunten

Marine emissions of dimethyl sulfide (DMS) to the atmosphere play a fundamental role in the global sulfur (5) cycle and have important consequences for the Earth's radiative balance. In the ocean, DMS is mainly produced by marine algae and bacteria via cle ...

AMER CHEMICAL SOC2019

Development of New Strategies of Umpolung with Cyclic Hypervalent Iodine Reagents

Paola Caramenti

Organic chemistry is essential for the development of a modern society and technical progress requires the continuous development of synthetic methodologies Novel, efficient, selective and flexible protocols are employed to access complex frameworks from s ...

EPFL2019

Efficiency improvement of an all-vanadium redox flow battery by harvesting low-grade heat

Hubert Girault, Danick Reynard, Christopher Raymond Dennison, Alberto Battistel

Redox flow batteries (RFBs) are rugged systems, which can withstand several thousand cycles and last many years. However, they suffer from low energy density, low power density, and low efficiency. Integrating a Thermally Regenerative Electrochemical Cycle ...

2018

Organic-sulfur poisoning of solid oxide fuel cell operated on bio-syngas

Stefan Diethelm, Jan Van Herle, Christian Ludwig, Hossein Madi

This study experimentally analyzes the performance and degradation issues of an anode supported (AS) Ni-YSZ solid oxide fuel cell exposed to thiophene (C4H4S). The impact of this organic sulfur compound on the performance of SOFC Ni-YSZ anodes is reported ...

Elsevier2016

Development of Accurate and Efficient Electronic Structure Approaches for the Description of Organic Systems

Riccardo Petraglia

The overarching objective of this thesis is extending and adapting the set of computational tools available for describing molecular precursors of organic semiconductors. The research presented within develops adhering to three principle goals: (1) provide ...

EPFL2016