Article
Engineering, Environmental
Hongru Shen, Defeng Zhao, Iida Pullinen, Sungah Kang, Luc Vereecken, Hendrik Fuchs, Ismail-Hakki Acir, Ralf Tillmann, Franz Rohrer, Juergen Wildt, Astrid Kiendler-Scharr, Andreas Wahner, Thomas F. Mentel
Summary: The study investigated the formation of gas-phase highly oxygenated organic molecules-organic nitrates (HOM-ON) from NO3-initiated oxidation of beta-pinene in the SAPHIR chamber. Results showed a mean molar yield of HOM-ON at 4.8%, with significant contributions to SOA formation, highlighting the importance of carbonylnitrates in the process.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Engineering, Environmental
Raphael Mayorga, Yu Xia, Zixu Zhao, Bo Long, Haofei Zhang
Summary: This study investigates the nighttime oxidation and secondary organic aerosol (SOA) formation mechanisms of limonene. The results show that limonene can be oxidized rapidly by ozone and nitrate radicals, leading to the formation of highly oxidized organic nitrates and nitrooxy peroxy radicals. Quantum chemical calculations and kinetic simulations reveal the main oxidation pathways, which explain the observed highly oxidized organic nitrates. The study also demonstrates the relevance of these mechanisms in the formation of organic aerosols in the nighttime atmosphere.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Olga E. Melkina, Vladimir A. Plyuta, Inessa A. Khmel, Gennadii B. Zavilgelsky
Summary: This study investigated the mechanisms of action of two volatile organic compounds on bacteria and found that (-)-limonene induces oxidative stress leading to DNA, protein, and membrane damage, while (+)-alpha-pinene only induces heat shock in bacteria. Additionally, it was shown that (-)-limonene completely inhibits the refolding process of heat-inactivated bacterial luciferase, while (+)-alpha-pinene partially inhibits this process in a mutant strain.
Article
Chemistry, Physical
Jean Philippe Renault, Stanislas Pommeret
Summary: In this study, first-principles molecular dynamics simulations based on density-functional theory were used to investigate the reactions of the solvated electron with nitrate or nitrous oxide. A strategy combining the in situ production of the aqueous electron followed by its reaction with either NO3- or N2O was devised. The simulations showed that electron transfer events occur on a sub-picosecond time scale and are controlled by the vibrational degree of freedom of the oxidants.
RADIATION PHYSICS AND CHEMISTRY
(2022)
Article
Chemistry, Organic
Thibaut Duhail, Tommaso Bortolato, Javier Mateos, Elsa Anselmi, Benson Jelier, Antonio Togni, Emmanuel Magnier, Guillaume Dagousset, Luca Dell'Amico
Summary: A light-driven method for the alpha-trifluoromethoxylation of ketones has been developed, showing good generality and efficiency under batch and flow conditions. The method demonstrates the potential in accessing a variety of elusive trifluoromethoxylated bioactive ingredients.
Article
Engineering, Environmental
Yu Wang, Tao Liu, Daocheng Gong, Hao Wang, Hai Guo, Minping Liao, Shuo Deng, Huang Cai, Boguang Wang
Summary: This study found that PAN was photochemically formed in the Nanling mountains of South China, with methylglyoxal, acetaldehyde, radicals, and other OVOCs as the main precursors. When polluted air masses invaded the area, anthropogenic aromatics intensified PAN formation. The net PAN formation reduced hydroxyl radical level, impaired local radical cycling, and suppressed local O3 production. These findings deepen our understanding of PAN photochemistry and the impact of anthropogenic intrusions on mountainous regions' background atmosphere.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Hari P. Upadhyaya
Summary: Kinetic studies were performed using computational methods to investigate the gas phase reaction between hydroxyl radical and tetrahydrothiophene, tetrahydrofuran, thio-phene, and furan. Rate coefficients were evaluated using the energy grained master equation solver based on energies of transition states and complexes calculated at G4MP2 level of theory. Different methods were used to optimize the structures and study their effectiveness and suitability. Theoretical rate coefficients were compared with experimental values, and the suitability of the method was discussed. It was observed that thiophene and furan exhibited multi-reference character, while tetrahydrothiophene and tetrahydrofuran results were reproduced with single reference methods.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Multidisciplinary Sciences
Dominique Grandjean, Caroline Elie, Capucine Gallet, Clotilde Julien, Vinciane Roger, Loic Desquilbet, Guillaume Alvergnat, Severine Delarue, Audrey Gabassi, Marine Minier, Laure Choupeaux, Solen Kerneis, Constance Delaugerre, Jerome Le Goff, Jean-Marc Treluyer
Summary: The study evaluates the diagnostic accuracy of canine olfaction in non-invasive detection of SARS-CoV-2 infection. The results show that canine detection has a high sensitivity and can be used as an alternative method in mass screening.
Article
Environmental Sciences
Xueqi Qiao, Mei Sun, Yifei Wang, Dong Zhang, Ruiqin Zhang, Bu Zhao, Jianbo Zhang
Summary: This study examined the relationship between PAN and PAN precursors using the RACM2 model in six episodes in Zhengzhou. Acetaldehyde oxidation was found to be the primary source of peroxyacetyl radical (PA), contributing over 70%. In photochemical and combined episodes, methylglyoxal and other radicals also played a role in PA formation. Alkene was identified as a first-generation precursor of PAN, while nitrous acid (HONO) promoted PAN formation in haze pollution. Sensitivity analysis revealed higher NOx/VOC ratios enhanced PAN sensitivity to HONO in photochemical and combined pollution.
ENVIRONMENTAL POLLUTION
(2023)
Article
Agriculture, Multidisciplinary
Jingwen Li, Zhixin Wang, Jonathan Crane, Yu Wang
Summary: This study investigated the contribution of volatile and non-volatile metabolites to the flavor variation of five carambola cultivars using a combination strategy of GC-MS/O-based volatilomics and LC-MS-based metabolomics. Several significant flavor-related pathways were identified, including amino acid biosynthesis or metabolism, terpenoids, fatty acids, sugar and organic acid, and flavonoids. The results showed that flavor traits of different carambola cultivars differed due to the up- or downregulation of metabolites in the flavor-related pathways. This study provides a valuable reference for breeders and researchers interested in the regulation of flavor.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2023)
Editorial Material
Plant Sciences
Sumit Ghosh
Summary: Forest vegetation emits terpene enantiomers, but their emission mechanisms and ecological functions are not well understood. In a study on tropical rainforest ecosystem, Byron et al. observed distinct diel trends and sources of enantiomer emission, as well as a significant change in (-)-alpha-pinene emission during severe drought, potentially promoting cloud formation.
TRENDS IN PLANT SCIENCE
(2023)
Article
Biochemistry & Molecular Biology
Fedor Y. Naumkin
Summary: Complexes of metal atoms with organic molecules are a class of systems with numerous applications, such as in metal-organic interfaces and organometallic chemistry. This study systematically investigates complexes with second-group metals, focusing on their structure, stability, charge distribution, polarity, and IR spectra. Three groups of isomers with different stability and physisorption or chemisorption characteristics are identified. Nonadditive stabilization in ternary systems and shape alterations of the aromatic component for different isomers and system sizes are also observed.
Article
Chemistry, Multidisciplinary
Marla P. DeVault, Anna C. Ziola, Paul J. Ziemann
Summary: Biogenic sources, particularly monoterpenes, are the main contributors to volatile organic compound (VOCs) emissions to the atmosphere. The reaction between monoterpenes and oxidants (such as OH radicals, NO3 radicals, or O-3) leads to the formation of oxidized products, some of which can form secondary organic aerosol (SOA) particles. This study investigates the reaction between NO3 radicals and five different monoterpenes, comparing their gas- and particle-phase products. The results provide insights into the role of molecular structure in VOC oxidation and particle-phase accretion reactions.
ACS EARTH AND SPACE CHEMISTRY
(2022)
Review
Environmental Sciences
Qi Pan, Qing-Yu Liu, Jing Zheng, Yan-Hong Li, Song Xiang, Xiao-Jie Sun, Xiao-Song He
Summary: Gas emitted from landfills contains a large quantity of volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs), some of which are carcinogenic, teratogenic, and mutagenic. The global hazards of VOCs and SVOCs in landfill gas to human health remain unclear. To quantify the global risk distributions of these pollutants, the composition and concentration data of VOCs and SVOCs from 72 landfills in 20 countries were collected and their human health risks were assessed. Organic compounds in landfill gas primarily result from the biodegradation of natural organic waste or the emissions and volatilization of chemical products. The respiratory system, particularly the lung, was found to be the major target organ of VOCs and SVOCs, with additional adverse health impacts ranging from headache and allergies to lung cancer. Aromatic and halogenated compounds were the primary sources of health risk, while ethyl acetate and acetone from the biodegradation of natural organic waste also exceeded the acceptable levels for human health. Overall, VOCs and SVOCs affected residents within 1,000 m of landfills. Air temperature, relative humidity, air pressure, wind direction, and wind speed were the major factors that influenced the health risks of VOCs and SVOCs. Currently, landfill risk assessments of VOCs and SVOCs are primarily based on respiratory inhalation, with health risks due to other exposure routes remaining poorly elucidated. In addition, potential health risks due to the transport and transformation of landfill gas emitted into the atmosphere should be further studied.
ENVIRONMENT INTERNATIONAL
(2023)
Article
Engineering, Environmental
Hao Wang, Haimei Wang, Keliang Wang, Jianyin Xiong, Shaodan Huang, Jack M. Wolfson, Petros Koutrakis
Summary: This study develops a two-layer analytical model to characterize the VOC/SVOC dermal uptake process, and extends it to predict VOC emissions from two-layer building materials or furniture. The key transport parameters of chemicals in every skin or material layer are determined via a hybrid optimization method using data from experiments and literature. The association between the absorption amount of studied chemicals into blood and age is preliminarily investigated, and dermal uptake is found to contribute significantly to the total exposure of examined SVOCs.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
