Publications related to Urea | EPFL Graph Search

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

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

Optical Urea Sensing in Sweat for Kidney Healthcare by Sensitive and Selective Non-enhanced Raman Spectroscopy

Christian Enz, Sandro Carrara, Assim Boukhayma, Ata Jedari Golparvar, Mattia Petrelli

Sweat biomarker analysis has attracted much interest in applications ranging from sports to wearable healthcare. Among all the sweat biomolecules, abnormal urea levels have been linked to several complications, particularly renal dysfunction. Here, we repo ...

SPIE-INT SOC OPTICAL ENGINEERING2023

The influence of the gas on the dynamics of cavitation bubbles

Davide Bernardo Preso

Cavitation bubbles, extensively investigated in fluid mechanics, present enduring challenges in hydraulic machinery, while holding considerable potential for practical applications in biomedicine and sonochemistry. Despite more than a century of research, ...

EPFL2023

Urea Derivative-Promoted CsPbl(2)Br Perovskite Solar Cells with High Open-Circuit Voltage

Bowen Yang, Yang Liu, Chen Li, Xin Guo

Inorganic perovskite solar cells (PSCs) have witnessed extraordinary advances owing to their prominent stability against thermal aging. However, they suffer from a phase transition from black phase to yellow phase under ambient conditions and serious energ ...

WILEY-V C H VERLAG GMBH2022

Poisoning of Mn-Ce/AC catalysts for low-temperature NH3-SCR of NO by K+ and its counter-ions (Cl- /NO3- /SO42- )

Oliver Kröcher, Davide Ferri, Rob Jeremiah G. Nuguid, Jie Yang

Mn-Ce/AC catalysts for low-temperature NH3-SCR of NOx were deliberately loaded with various potassium salts (KCl, KNO3, and K2SO4) to investigate the influence of the counter-ions on the poisoning impact. Whereas K salts poisoning had only marginal impact ...

ELSEVIER2022

In situ spectroscopic studies of the effect of water on the redox cycle of Cu ions in Cu-SSZ-13 during selective catalytic reduction of NOx

Oliver Kröcher, Davide Ferri, Rob Jeremiah G. Nuguid

The effect of water on the NH3-assisted selective catalytic reduction of NOx (NH3-SCR) has been largely neglected, despite the inevitable presence of water vapor in real emissions produced by fuel combustion. In this work, we investigated the role of water ...

Royal Society of Chemistry2022

Dynamic partitioning of branched-chain amino acids-derived nitrogen supports renal cancer progression

Vassily Hatzimanikatis, Maria Masid Barcon, Ming Yang

Metabolic reprogramming is critical for tumor initiation and progression. However, the exact impact of specific metabolic changes on cancer progression is poorly understood. Here, we integrate multimodal analyses of primary and metastatic clonally-related ...

Nature Portfolio2022

Monomeric Fe Species in Square Planar Geometry Active for Low Temperature NH3-SCR of NO

Oliver Kröcher, Davide Ferri

Monomeric Fe species in zeolites are considered to be the active sites for the low temperature activity toward ammonia-assisted selective catalytic reduction of nitrogen oxides (NH3-SCR) in exhaust gases. Herein, we report on a preparation method to synthe ...

AMER CHEMICAL SOC2022

Method and system for producing a carbonate-containing species-rich, nitrogen-containing species-free solution

Lyesse Laloui, Dimitrios Terzis

A method for producing a carbonate-containing species-rich, nitrogen-containing species-free solution from a urea-rich solution is proposed. The method comprising the steps of: providing a first reservoir comprising a first mixture including urea and a cat ...

2021

Boosting hydrogen production via urea electrolysis on an amorphous nickel phosphide/graphene hybrid structure

Paul Joseph Dyson, Zhaofu Fei, Lu Chen, Yun Tong

Overall urea electrolysis has favorable thermodynamic properties and can complement traditional water splitting by simultaneously purifying urea-rich waste streams. However, the kinetics of the reaction is slow and more efficient catalysts are required. In ...

SPRINGER2021

Diamine Synthesis via the Nitrogen-Directed Azidation of sigma- and pi-C-C Bonds

Jérôme Waser, Mingming Wang

Diamines are essential building blocks for the synthesis of agrochemicals, drugs, and organic materials, yet their synthesis remains challenging, as both nitrogens need to be differentiated and diverse substitution patterns (1,2, 1,3, or 1,4) are required. ...

2021

A Two Step Postsynthetic Modification Strategy: Appending Short Chain Polyamines to Zn-NH2-BDC MOF for Enhanced CO2 Adsorption

Wendy Lee Queen, Jordi Espin Marti, Mehrdad Asgari, Olga Trukhina, Ilia Kochetygov, Anita Justin

Functionalizing metal–organic frameworks (MOFs) with amines is a commonly used strategy to enhance their performance in CO2 capture applications. As such, in this work, a two-step strategy to covalently functionalize NH2-containing MOFs with short chain po ...

2021

Self-Propulsion of Active Colloids via Ion Release: Theory and Experiments

Ignacio Pagonabarraga Mora, Samuel Sanchez

We study the self-propulsion of a charged colloidal particle that releases ionic species using theory and experiments. We relax the assumptions of thin Debye length and weak nonequilibrium effects assumed in classical phoretic models. This leads to a numbe ...

2020

High-resolution cryo-EM structure of urease from the pathogen Yersinia enterocolitica

Henning Paul-Julius Stahlberg, Jasenko Zivanov

Urease converts urea into ammonia and carbon dioxide and makes urea available as a nitrogen source for all forms of life except animals. In human bacterial pathogens, ureases also aid in the invasion of acidic environments such as the stomach by raising th ...

Nature Research2020

Cellulose phosphorylation comparison and analysis of phosphorate position on cellulose fibers

David Lyndon Emsley, Jayasubba Reddy Yarava, Michel Bardet, Julien Bras

Chemical modifications of cellulose fibers as pretreatment for cellulose nanofibrils (CNF) production have been investigated to improve the production process and the quality of obtained cellulosic nanomaterial. In this study, phosphorylation of cellulose ...

ELSEVIER SCI LTD2020

C-13 Dynamic Nuclear Polarization using SA-BDPA at 6.7 T and 1.1 K: Coexistence of Pure Thermal Mixing and Well-Resolved Solid Effect

Rolf Gruetter, Andrea Capozzi, Hikari Ananda Infinity Yoshihara, Alice Radaelli

SA-BDPA is a water-soluble, narrow-line width radical previously used for dynamic nuclear polarization (DNP) signal enhancement in solid-state magic angle spinning NMR spectroscopy. Here, we report the first study using SA-BDPA under dissolution DNP condit ...

AMER CHEMICAL SOC2020

Selective Catalytic Reduction of NO with NH3 on Cu-SSZ-13: Deciphering the Low and High-temperature Rate-limiting Steps by Transient XAS Experiments

Oliver Kröcher, Davide Ferri, Adrian Marberger, Patrick Simon Steiger, Rob Jeremiah G. Nuguid

Cu-exchanged small-pore SSZ-13 catalysts have found wide use for the selective catalytic reduction (SCR) of nitrogen oxides from automotive exhaust gases. The transient working environment of the Cu-SSZ-13 catalyst during NH3-SCR requires studying the rate ...

Wiley-VCH Verlag2020

Techno-economic comparison of green ammonia production processes

François Maréchal, Jan Van Herle, Ligang Wang, Hanfei Zhang

To reduce the fossil-fuel consumption and the impacts of conventional ammonia production on climate change, green ammonia production processes using green hydrogen need to be investigated. For commercial production scale, potential alternatives can be base ...

2020

Ammonium is the preferred source of nitrogen for planktonic foraminifer and their dinoflagellate symbionts

Anders Meibom, Charlotte Madeleine Nicole Lekieffre, Emmanuelle Geslin

The symbiotic planktonic foraminiferaOrbulina universainhabits open ocean oligotrophic ecosystems where dissolved nutrients are scarce and often limit biological productivity. It has previously been proposed thatO. universameets its nitrogen (N) requiremen ...

ROYAL SOC2020

Pivotal Role of the Basic Character of Organic and Salt Catalysts in C-N Bond Forming Reactions of Amines with CO2

Paul Joseph Dyson, Martin Hulla

Organocatalysts promote a range of C-N bond forming reactions of amines with CO2. Herein, we review these reactions and attempt to identify the unifying features of the catalysts that allows them to promote a multitude of seemingly unrelated reactions. Ana ...

Wiley-VCH Verlag GmbH2020