Publications associées à Indicateur de pH

Silicon microresonator arrays: A comprehensive study on fabrication techniques and pH-controlled stress-induced variations in cantilever stiffness

Luis Guillermo Villanueva Torrijo, Annalisa De Pastina

We introduce a detailed design and fabrication process of Silicon microcantilever arrays for biomolecular detection in liquid environment, utilized with laser readout. We present typical fabrication problems and provide related solutions to obtain high qua ...

Elsevier2024

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, Giulio Farinelli, Ogadimma Cassandra Oji-Okoro

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

Acids from fruits generate photoactive Fe-complexes, enhancing solar disinfection of water (SODIS): A systematic study of the novel " fruto-Fenton " process, effective over a wide pH range (4-9)

César Pulgarin, Aline Laetitia Schaub, Stefanos Giannakis, Giulio Farinelli, Mona Kohantorabi

This study aimed to enhance solar disinfection (SODIS) by the photo-Fenton process, operated at natural pH, through the re-utilization of fruit wastes. For this purpose, pure organic acids present in fruits and alimentary wastes were tested and compared wi ...

Pergamon-Elsevier Science Ltd2024

Beyond the coupled distortion model: structural analysis of the single domain cupredoxin AcoP, a green mononuclear copper centre with original features

Luciano Andres Abriata

Cupredoxins are widely occurring copper-binding proteins with a typical Greek-key beta barrel fold. They are generally described as electron carriers that rely on a T1 copper centre coordinated by four ligands provided by the folded polypeptide. The discov ...

Royal Soc Chemistry2024

Microstructure - Electrochemical Surface Reactivity Relationship of Electrochemically Grown Manganese Oxides Films

Roberto Cestaro

This Thesis provides a comprehensive and correlative investigation of the microstructure, chemical state, and electrochemical reactivity of manganese oxide (MnOx) films, aiming to gain a deeper understanding of the deposition and dissolution mechanism of M ...

EPFL2024

Bacterial inactivation in sunlit surface waters is dominated by reactive species that emanate from the synergy between light, iron, and natural organic matter

César Pulgarin, Stefanos Giannakis, Jun Ma, Da Wang, Shuang Song

In this study, the synergistic and antagonistic effects of Fe species and coexisting natural organic matter (NOM) on the efficacy of solar light disinfection of water are investigated. Different initial iron species (Fe2+/Fe3+) and naturalorganic matter ty ...

Elsevier2023

Development of a magnetic calcium-alginate hydrogel-sphere encapsulated with Fe-Mn-Zr ternary metal composite for heavy metal adsorption

Xinyi Huang

Heavy metal contamination has become one of the greatest global environmental problems. In this study, a magnetic calcium-alginate hydrogel-sphere encapsulated with Fe-Mn-Zr ternary-metal composite (MCHETC) was prepared through a combined co-precipitation ...

2023

Expiratory Aerosol pH is a Driver of the Persistence of Airborne Influenza A Virus

Aline Laetitia Schaub

To mitigate the spread of a viral disease, it is crucial to understand the factors that influence airborne virus transmission. However, the micro-environment to which the virus is exposed in expiratory aerosol particles is highly complex. The relative humi ...

SWISS CHEMICAL SOC2023

Sunshine and a pinch of tropical soils: A natural, low-cost photo-Fenton variation for safer water, assisted by H2O2 or percabonate

César Pulgarin, Michaël Bensimon, Stefanos Giannakis, Thomas Guillaume, Jérémie Decker

Clean water is essential for human survival, but access to safe drinking water remains a challenge in resource -limited regions. Herein, we explored a low-cost but effective solution for water potabilization using natural iron sources from soils along with ...

ELSEVIER2023

Visible-light driven water oxidation and oxygen production at soft interfaces

Hubert Girault, Astrid Johana Olaya Avendano, Jorge Gustavo Uranga, Julieta Soledad Riva, Sara Natalia Moya Betancourt

The visible light driven water oxidation reaction (WOR) by the organic electron acceptor 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-quinodimethane (TCNQF(4)) was studied at the water|butyronitrile interface. The WOR was performed at neutral pH, and without any ...

Royal Society of Chemistry2022

Al uptake in calcium silicate hydrate and the effect of alkali hydroxide

Karen Scrivener, Barbara Lothenbach, Yan Yan

The effect of Al and of pH on the structure of calcium silicate hydrate (C-S-H), the most important hydration product in Portland and blended cement, was studied at Ca/Si similar to 1.0. The presence of Al led to higher amounts of secondary phases, larger ...

Pergamon-Elsevier Science Ltd2022

Configurable Organic Electrochemical Transistors with Printed Functional Materials for Multiplexed Sweat Analysis

Silvia Demuru

Monitoring human sweat with wearable biochemical sensors could give insights into the hydration, fatigue, and health status, tracking the variations of biomarkers non-invasively and in real-time. In this field, organic electrochemical transistors (OECTs) a ...

EPFL2022

Effect of alkali, aluminium and equilibration time on calcium-silicate-hydrates

Yu Yan

Calcium silicate hydrate (C-S-H) is the main hydration product in Portland and blended cements, and greatly affects durability and mechanical properties of the hydrated cement. In the presence of Al-rich supplementary cementitious materials (SCMs), C-(A-)S ...

EPFL2022

Effect of different ions on dissolution rates of silica and feldspars at high pH

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri, Mahdieh Shakoorioskooie

The dissolution kinetics of silica-containing minerals in aggregates influences strongly the process of ASR in concrete. In this paper, the effect of different ions on the dissolution rates of SiO2 (amorphous and quartz) and feldspars at high pH values was ...

Pergamon-Elsevier Science Ltd2022

Biostimulation as a sustainable solution for acid neutralization and uranium immobilization post acidic in-situ recovery

Rizlan Bernier-Latmani, Pierre Rossi, Thomas Coral

Major uranium (U) deposits worldwide are exploited by acid leaching, known as 'in-situ recovery' (ISR). ISR involves the injection of an acid fluid into ore-bearing aquifers and the pumping of the resulting metal-containing solution through cation exchange ...

2022

Expiratory Aerosol pH: The Overlooked Driver of Airborne Virus Inactivation

Tamar Kohn, Athanasios Nenes, Kalliopi Violaki, Ghislain Gilles Jean-Michel Motos, Walter Hugentobler, Aline Laetitia Schaub, Shannon Christa David

Respiratory viruses, including influenza virus and SARS-CoV-2, are transmitted by the airborne route. Air filtration and ventilation mechanically reduce the concentration of airborne viruses and are necessary tools for disease mitigation. However, they ign ...

2023

Active sites on copper-based catalysts for electrochemical CO2 reduction selectively to C2+ products

Jie Zhang

Electrochemical CO2 reduction (eCO2RR) towards value-added chemicals, powered by renewable electricity, is a promising technology for storing the intermittent renewable energy in the form of chemical bonds. Among the various products of eCO2RR, multi-carbo ...

EPFL2022

The effect of paste composition, aggregate mineralogy and temperature on the pore solution composition and the extent of ASR expansion

Karen Scrivener, Barbara Lothenbach, Mahsa Bagheri

The reaction kinetics of the alkali silica reaction depends on the composition of the pore solution. The evolution of the pore solution composition in different cement pastes and concretes was studied. Pastes containing silica fume or metakaolin had the lo ...

SPRINGER2022

Bulk Heterojunction Organic Semiconductor Photoanodes: Tuning Energy Levels to Optimize Electron Injection

Kevin Sivula, Jun Ho Yum, Liang Yao, Nestor Guijarro Carratala, Yongpeng Liu, Arvindh Sekar, Han-Hee Cho, Barbara Alexandra Primera Darwich, Juan Manuel Moreno Naranjo

The use of a bulk heterojunction of organic semiconductors to drive photoelectrochemical water splitting is an emerging trend; however, the optimum energy levels of the donor and acceptor have not been established for photoanode operation with respect to e ...

AMER CHEMICAL SOC2022

Molecular insights into the electrical double layer of colloidal oxide particles obtained through second harmonic scattering

Marie Bischoff

Photocatalytic applications play an essential role in the search for alternative energy sources and environmental decontamination techniques. It is of fundamental interest to understand on a molecular level the aqueous solid/liquid interface, where photoca ...

EPFL2022