Article
Environmental Sciences
Alexandra Tevlin, Elisabeth Galarneau, Tianchu Zhang, Hayley Hung
Summary: The concentrations of polycyclic aromatic compounds (PACs) in Canadian air and deposition show large variations, with higher levels near industrial emitters and lower levels in the Arctic. Reductions in industrial emissions can influence the environment near relevant facilities, but the impact in other areas is modest. Future research is needed to further investigate PACs in Canada.
ENVIRONMENTAL POLLUTION
(2021)
Article
Chemistry, Multidisciplinary
Ya Zou, Yi Han, Shaofei Wu, Xudong Hou, Chi Hao Eugene Chow, Jishan Wu
Summary: A planar dibenzo-peri-hexacene derivative was synthesized via FeCl3-mediated Scholl reaction, but an unexpected octagon-containing molecule was obtained when using DDQ and MeSO3H, with similar results confirmed under other conditions. X-ray crystallographic analysis showed no close pi-pi stacking, and DFT calculations revealed different mechanisms for the formation of hexagons and octagons under different conditions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Food Science & Technology
Yuzhu Li, Kezhou Cai, Gaofeng Hu, Qianhui Gu, Peijun Li, Baocai Xu, Conggui Chen
Summary: The study evaluated the influence of six sodium-reducing treatments on the formation of polycyclic aromatic hydrocarbons (PAHs) in baked bacon. Results showed that different treatments had varied effects on PAHs formation, likely involving Maillard reactions. pH adjustment played a crucial role in the impact of substitute salts on the generation of PAH4.
Article
Chemistry, Physical
Meng-Xu Jiang, Ioannis C. Giannakidis, Peter C. Samartzis, Agust Kvaran
Summary: Mass resolved REMPI spectra and electron and ion velocity map images were used to study the multiphoton-fragmentation processes of acetylene. The results showed that the formation of fragment ions increased with excitation energy and the three-photon dissociation processes played a significant role. The data also provided insights into secondary photodissociation processes and fragment energetics.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Mengna Zhao, Sai Ho Pun, Qi Gong, Qian Miao
Summary: The synthesis of new carbazole-fused polycyclic aromatics with interesting geometry and useful properties was explored using Scholl reactions. The oxidative coupling of carbazole units occurred in a regioselective manner, forming new carbon-carbon bonds preferably at C3 and C4 in N-alkyl carbazoles. A new N-containing aromatic bowl was characterized, and new p-type organic semiconductors exhibited field effect mobility of up to 0.070 cm(2) V-1 s(-1) in solution-processed thin-film transistors.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Environmental Sciences
Jiangyao Chen, Jiani Li, Xiaoyan Chen, Jianwei Gu, Taicheng An
Summary: This study investigates the interconversion between monocarbonyls and dicarbonyls and their role in the production of secondary organic aerosols (SOA) during the photochemical oxidation of aromatic hydrocarbons. The results show that the formation of monocarbonyls leads to a decrease in SOA production, while the presence of OH radicals affects the balance of photolysis and influences SOA formation. These interconversion reactions play a significant role in reducing SOA production.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Chemistry, Applied
Gizem Goker, Sezer Kiralan, Aziz Tekin, Ferruh Erdogdu
Summary: The study found that the formation of PAHs in olive pomace during drying is influenced by temperature and time, with the total PAH formation rate increasing with temperature. The activation energy and frequency factor values also increase as temperature rises.
Article
Thermodynamics
Chia Chun Lee, Manh-Vu Tran, Boon Thong Tan, Gianfranco Scribano, Cheng Tung Chong, Jong Boon Ooi
Summary: The study found that the addition of ethanol can increase the concentration of aromatic substances in methane diffusion flames, with the chemical effect being the main factor, followed by the dilution effect and the thermal effect. The increase in pressure accelerates the production of aromatics, as the narrowing of the flames improves air entrainment and significantly speeds up overall reactivity.
Article
Chemistry, Multidisciplinary
Tingting Zhang, Guizhi Mu, Shourong Zhang, Jialin Hou
Summary: The study investigated the reaction pathways from phenyl radicals to PAHs through addition reactions with C2H3 and C4H4, utilizing the G3 method to calculate rate constants and evaluating the influence of different additions on reaction rates. The improved model showed effectiveness in promoting PAH formations, with the C4H4 addition pathways being particularly beneficial for PAH formation in butane flames.
Article
Chemistry, Physical
Anita Schneiker, Gopi Ragupathy, Gabor Bazso, Gyorgy Tarczay
Summary: It is well-accepted that the formation of interstellar H-2 is catalyzed by small heterocycles on the surface of interstellar grains. This study investigated the reaction of H atoms with different heterocycles in solid para-H-2. The results revealed the formation of various radicals and suggested the important role of small heterocycles in interstellar H-2 formation. Additionally, it was found that the ratios of different c-C4HxO (x = 4-8) species in an astrophysical object are determined by the rate of H atom addition and abstraction reactions.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Energy & Fuels
Qiaojing Zhao, Shenjun Qin, Wenchao Shen, Yuzhuang Sun
Summary: Sulfur-containing polycyclic aromatic compounds (SPACs) are important compounds found in coal, and the different forms of sulfur in coal can affect their formation. By studying samples from the Yuzhou Coalfield and Dengfeng Coalfield, it was found that different sulfur forms lead to variations in SPAC content.
Article
Geochemistry & Geophysics
Marceau Lecasble, Laurent Remusat, Jean-Christophe Viennet, Boris Laurent, Sylvain Bernard
Summary: Carbonaceous chondrites contain various soluble compounds, including polycyclic aromatic hydrocarbons (PAHs). The origin of PAHs in these chondrites is debated, but they may provide information about accretion and alteration processes. The size and isotopic composition of PAHs can reveal information about these processes.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Engineering, Environmental
Bingcheng Lin, Guorui Liu, Guanglong Wu, Changzhi Chen, Yong Liang, Pu Wang, Jianping Guo, Lili Yang, Rong Jin, Yuxiang Sun, Minghui Zheng
Summary: This study simultaneously determined multiple organic pollutants in various stages of industrial-scale secondary copper smelting plants and revealed that the unintentional production and release of PBDEs from this industry is a concern. The formation pathway of brominated PAHs is consistent with that of chlorinated PAHs, while PBDD/Fs can also be formed from PBDEs as precursors.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Engineering, Environmental
Wenlong Li, Richard Park, Nick Alexandrou, Helena Dryfhout-Clark, Ken Brice, Hayley Hung
Summary: PAH concentrations in the Great Lakes Basin atmosphere have decreased between 1997 and 2017, with potential sources identified as coal, liquid fossil fuel, and biomass burning. The potential source regions for most sectors were located to the south or southwest of the sampling sites.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2021)
Article
Engineering, Environmental
Linjie Zhang, Lilan Zhang, Yue Shi, Zhihui Yang, Qijun Gong, Dong Sun
Summary: This study developed a method to quantify the variability of oceanic PAHs based on wind frequency and wind-speed-weighted wind frequency. The validity of this method was tested using in-situ survey data and publicly available data from other monsoonal open oceans. The results showed that wind frequency and wind-speed-weighted wind frequency could better explain the variation of dissolved and particulate PAHs in the surface ocean, respectively. This study suggests that the influence of seasonal atmospheric transport is important in describing and interpreting the distribution patterns of PAHs in monsoon-influenced low and mid-latitude open oceans, and provides a reference method for understanding the global-scale distribution patterns of PAHs in the ocean.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
