The generation and transformation mechanisms of reactive oxygen species in the environment and their implications for pollution control processes: a review.

Environmental Research, Journal Year: 2024, Volume and Issue: 260, P. 119592 - 119592

Published: July 14, 2024

Language: Английский

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Metal-catalyzed asymmetric reactions enabled by organic peroxides

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(5), P. 2326 - 2349

Published: Jan. 1, 2024

This review summarizes the advances in metal-catalyzed asymmetric reactions enabled by organic peroxides that have been found to exhibit multifunctionalities, for instance, applied as stoichiometric reactants, reagents, or catalytic amount reagents.

Language: Английский

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Rapid and Highly Selective Fe(IV) Generation by Fe(II)-Peroxyacid Advanced Oxidation Processes: Mechanistic Investigation via Kinetics and Density Functional Theory

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 14, 2024

High-valent iron (Fe(IV/V/VI)) has been widely applied in water decontamination. However, common Fe(II)-activating oxidants including hydrogen peroxide (H

Language: Английский

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Reactive Oxygen Species Formation and Peroxide and Carbonyl Decomposition in Aqueous Photolysis of Secondary Organic Aerosols

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(10), P. 4716 - 4726

Published: Feb. 27, 2024

The mechanism and kinetics of reactive oxygen species (ROS) formation when atmospheric secondary organic aerosol (SOA) is exposed to solar radiation are poorly understood. In this study, we combined an in situ UV–vis irradiation system with electron paramagnetic resonance (EPR) spectroscopy characterize the photolytic ROS aqueous extracts SOA formed by oxidation isoprene, α-pinene, α-terpineol, toluene. We observed substantial free radicals, including •OH, superoxide (HO2•), radicals (R•/RO•) upon irradiation. Compared dark conditions, radical yield was enhanced a factor ∼30 for •OH 2–10 emergence radicals. Total peroxide measurements showed decreases contents after photoirradiation, indicating that peroxides can be important source A liquid chromatography interfaced high-resolution mass spectrometry used detect number form adducts spin trap, BMPO. types detected photolysis model compounds indicated carbonyls Norrish type I mechanisms plays role formation. serves as driving force cloud fog processing SOA.

Language: Английский

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Observational evidence for Criegee intermediate oligomerization reactions relevant to aerosol formation in the troposphere

Nature Geoscience, Journal Year: 2024, Volume and Issue: 17(3), P. 219 - 226

Published: March 1, 2024

Language: Английский

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Photocatalytic O2 activation carried out by organic aerosol: A case study of 1, 8-naphthalic anhydride

Applied Catalysis B Environment and Energy, Journal Year: 2024, Volume and Issue: 349, P. 123889 - 123889

Published: April 24, 2024

Language: Английский

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Ozone Loss: A Surrogate for the Indoor Concentration of Ozone-Derived Products

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(36), P. 13569 - 13578

Published: Aug. 28, 2023

Ozone concentrations tend to be substantially lower indoors than outdoors, largely because of ozone reactions with indoor surfaces. When there are no sources ozone, a common condition, the net concentration gaseous products derived from chemistry scales linearly difference between outdoor and concentrations, termed "ozone loss." As such, loss is metric that might used by epidemiologists disentangle adverse health effects ozone's oxidation those exposure itself. The present paper examines characteristics, potential utility, limitations concept. We show for commonly occurring conditions, directly proportional total rate constant removal on surfaces (ksum) inversely air exchange (λ) plus surface (ksum). It follows ratio equal λ ksum. promising probing resulting exposures chemistry. Notwithstanding its virtues, practitioners using it should mindful discussed in this paper.

Language: Английский

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Temperature-Dependent Composition of Summertime PM_2.5 in Observations and Model Predictions across the Eastern U.S.

ACS Earth and Space Chemistry, Journal Year: 2024, Volume and Issue: 8(2), P. 381 - 392

Published: Feb. 5, 2024

Throughout the U.S., summertime fine particulate matter (PM2.5) exhibits a strong temperature (T) dependence. Reducing PM2.5 enhancement with T could reduce public health burden of now and in warmer future. Atmospheric models are critical tool for probing processes components driving observed behaviors. In this work, we describe how modeled aerosol abundance composition vary present-day Eastern specific attention to two major components: sulfate (SO42–) organic carbon (OC). Observations U.S. show an average measured PM2.5-T sensitivity 0.67 μg/m3/K, CMAQv5.4 regional model predictions closely matching value. Observed SO42– OC also increase T; however, has component-specific discrepancies observations. Specifically, underestimates concentrations their while overestimating T. Here, explore series interventions aimed at correcting these deviations. We conclude that relationship is driven by inorganic systems highly coupled, it possible design simultaneously address biases component as well responses

Language: Английский

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Applications of environmental mass spectrometry in atmospheric haze chemistry

TrAC Trends in Analytical Chemistry, Journal Year: 2024, Volume and Issue: 172, P. 117614 - 117614

Published: Feb. 21, 2024

Language: Английский

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Selecting Initial Conditions for Trajectory-Based Nonadiabatic Simulations

Accounts of Chemical Research, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 9, 2025

ConspectusPhotochemical reactions have always been the source of a great deal mystery. While classified as type chemical reaction, no doubts are allowed that general tenets ground-state chemistry do not directly apply to photochemical reactions. For typical understanding critical points potential (free) energy surface and embedding them in thermodynamics framework is often enough infer reaction yields or characteristic time scales. A working principle profile along minimum paths provides key information characterize reaction. These well-developed concepts, unfortunately, rarely stretch processes involving formation nonstationary state for molecular system after light absorption.Upon photoexcitation, molecule likely undergo internal conversion processes, is, changes electronic states mediated by couplings between nuclear motion, precisely what celebrated Born–Oppenheimer approximation neglects. coupled electron–nuclear coined nonadiabatic allow decay from one other nonradiatively. Understanding intricate dynamics pivotal rationalizing predicting outcome photoexcitation providing insights experiments conducted, example, advanced sources such free-electron lasers.Nowadays, most simulations based on approximations invoke near-classical depiction nuclei. This reliance due practical constraints, classical equations motion nuclei must be supplemented techniques hopping account transitions states. but overlooked aspect these selection initial conditions, specifically choice positions momenta dynamics, which can significantly influence how well mimic real quantum systems across various experimental scenarios. The conventional approach generating conditions typically maps onto phase space using Wigner quasiprobability function within harmonic approximation, followed second where undergoes sudden excitation.In this Account, we aim warn experienced user about possible limitations strategy initial-condition generation its inability accurately describe molecule. More specifically, argue phase-space distribution more represented through thermostat. method offers robust applied large, flexible, even solvated systems. Furthermore, reliability benchmarked against rigorous approaches path integral dynamics. Additionally, commonly used assumes vertical excitation molecule, reflects triggered laser pulses actual spectroscopic experiments. We discuss here generate any pulse. also strategies tackle continuous-wave laser.

Language: Английский

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