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1. A general approach to non-fullerene electron acceptors based on the corannulene motif

Author:
Barát, Viktor; Budanović, Maja; Halilovic, Dzeneta; Huh, June; Webster, Richard D.; Mahadevegowda, Surendra H.; Stuparu, Mihaiela C.
Source:
Chemical communications 2019 v.55 no.21 pp. 3113-3116
ISSN:
1364-548X
Subject:
polycyclic aromatic hydrocarbons,   etc   ; fullerene; oxidation; sulfur;     Show all 4 Subjects
Abstract:
... Here, we show that oxidation of exo-cyclic sulfur atoms enhances the molecular reduction potential of non-planar polycyclic aromatic hydrocarbons and allows for a systematic bridging of the electron affinity gap between corannulene, a fragment of fullerene C₆₀, and the prevalent fullerene-based electron acceptor phenyl-C₆₁-butyric acid methyl ester (PCBM). ...
DOI:
10.1039/c9cc00327d

2. Analytical progress and challenges for the detection of oxygenated polycyclic aromatic hydrocarbon transformation products in aqueous and soil environmental matrices: A review

Author:
Pulleyblank, Coren; Cipullo, Sabrina; Campo, Pablo; Kelleher, Brian; Coulon, Frederic
Source:
Critical reviews in environmental science and technology 2019 v.49 no.5 pp. 357-409
ISSN:
1547-6537
Subject:
polycyclic aromatic hydrocarbons,   etc   ; analytical methods; soil; toxicity;     Show all 4 Subjects
Abstract:
... Over the past 20 years, a growing body of research has raised concerns about the toxicity, fate, and transport of oxygenated transformation products of polycyclic aromatic hydrocarbons. Research targeting these diverse compounds in soil and water systems has been challenged by a lack of standard analytical techniques and suitable reference materials. However, recent efforts towards the consolidati ...
DOI:
10.1080/10643389.2018.1547622

3. Molecular insights into the initial formation of pyrolytic carbon upon carbon fiber surface

Author:
Chen, MingWei; Zhu, YinBo; Xia, Jun; Wu, HengAn
Source:
Carbon 2019 v.148 pp. 307-316
ISSN:
0008-6223
Subject:
polycyclic aromatic hydrocarbons,   etc   ; carbon; carbon fibers; microstructure; temperature;     Show all 5 Subjects
Abstract:
... Understanding the deposition process of pyrolytic carbon is essential in controlling its microstructure and consequent macroscale performance. Herein, using molecule dynamics (MD) simulations with the ReaxFF potential, we revealed the initial formation process of pyrolytic carbon near the simplified surface of carbon fiber. Three stages were identified in the deposition process, where polycyclic a ...
DOI:
10.1016/j.carbon.2019.04.003

4. The presence of nitroarenes formed by secondary atmospheric processes in the Japanese freshwater environment

Author:
Nagato, Edward G.; Hayakawa, Kazuichi
Source:
Environmental pollution 2019 v.250 pp. 554-558
ISSN:
0269-7491
Subject:
polycyclic aromatic hydrocarbons,   etc   ; automobiles; combustion; ecotoxicology; freshwater; isomers;     Show all 6 Subjects
Abstract:
... In this study, the concentrations and distributions of nitrated polycyclic aromatic hydrocarbons (NPAHs) were characterized in the freshwater environment of a Japanese city. While the NPAHs were few in number, they were found in pg/L concentrations and the specific isomers suggested the deposition of NPAHs formed via the atmospheric transformation of PAHs. The absence of NPAHs formed via primary c ...
DOI:
10.1016/j.envpol.2019.04.049

5. Multi-particle frits for packed capillary columns in electrochromatographic use

Author:
Sun, Jiannan; Yang, Shiwei; Cheng, Heyong; Wang, Yuanchao; Liu, Jinhua
Source:
Journal of chromatography 2019 v.1595 pp. 221-229
ISSN:
0021-9673
Subject:
polycyclic aromatic hydrocarbons,   etc   ; electrochromatography; mechanical properties; packaging materials; permeability; slurries;     Show all 6 Subjects
Abstract:
... Further development of capillary electrochromatography (CEC) is to some extent restricted by column technology. Packed capillary columns are most commonly used in CEC because of higher sample capacity and higher sensitivity than open tubular columns, and better reproducibility and uniformity than monolithic columns. Fritting is the core component for the fabrication of packed capillary columns. Th ...
DOI:
10.1016/j.chroma.2019.02.046

6. Evolving Fluorophores into Circularly Polarized Luminophores with a Chiral Naphthalene Tetramer: Proposal of Excimer Chirality Rule for Circularly Polarized Luminescence

Author:
Takaishi, Kazuto; Iwachido, Kazuhiro; Takehana, Ryosuke; Uchiyama, Masanobu; Ema, Tadashi
Source:
Journal of the American Chemical Society 2019 v.141 no.15 pp. 6185-6190
ISSN:
1520-5126
Subject:
polycyclic aromatic hydrocarbons,   etc   ; fluorescence; fluorescent dyes; optical isomerism;     Show all 4 Subjects
Abstract:
... A versatile method for converting various fluorescent polycyclic aromatic hydrocarbons into circularly polarized luminescence (CPL) excimer dyes with high gₗᵤₘ and ΦFL values is reported. This method involves the functionalization of a chiral quaternaphthyl with six fluorophores via ester linkages in the last step of the synthesis. The usefulness of this approach was demonstrated for 1-, 2-, and 4 ...
DOI:
10.1021/jacs.9b02582

7. Valence Bond Account of Triangular Polyaromatic Hydrocarbons with Spin: Combining Ab Initio and Phenomenological Approaches

Author:
Toader, Ana M.; Buta, Cristina M.; Frecus, Bogdan; Mischie, Alice; Cimpoesu, Fanica
Source:
Journal of physical chemistry 2019 v.123 no.11 pp. 6869-6880
ISSN:
1932-7455
Subject:
polycyclic aromatic hydrocarbons,   etc   ; density functional theory; electrons; physical chemistry; prediction;     Show all 5 Subjects
Abstract:
... We present computational analyses, methodological advances, and heuristic conclusions applied on a series of polyaromatic systems condensed in the shape of regular triangles, carrying spin, because of topological reasons. A new clue about the classification of title systems in three equivalency classes is presented. A conjugated hydrocarbon having n-hexagonal rings at one edge, carrying n – 1 unpa ...
DOI:
10.1021/acs.jpcc.8b12250

8. NBN-embedded Polycyclic Aromatic Hydrocarbons Containing Pentagonal and Heptagonal Rings

Author:
Fu, Yubin; Zhang, Ke; Dmitrieva, Evgenia; Liu, Fupin; Ma, Ji; Weigand, Jan J.; Popov, Alexey A.; Berger, Reinhard; Pisula, Wojciech; Liu, Junzhi; Feng, Xinliang
Source:
Organic letters 2019 v.21 no.5 pp. 1354-1358
ISSN:
1523-7052
Subject:
polycyclic aromatic hydrocarbons,   etc   ; X-radiation; chemical structure; electronics; oxidation; transistors;     Show all 6 Subjects
Abstract:
... Two novel nonhexagonal ring fused NBN-dibenzophenalenes (NBN-penta and NBN-hepta) were designed and synthesized. X-ray analysis reveals the planar structure of NBN-penta, while NBN-hepta displays a double-helical structure. Both compounds possess higher oxidation potential compared to the NBN-type zigzag-edged polycyclic aromatic hydrocarbons. The resultant NBN-penta and NBN-hepta exhibit global a ...
DOI:
10.1021/acs.orglett.9b00057

9. Structures of carbonaceous nanoparticles formed in various pyrolysis systems

Author:
Jander, Helga; Borchers, Christine; Böhm, Heidi; Emelianov, Alexander; Schulz, Christoph
Source:
Carbon 2019 v.150 pp. 244-258
ISSN:
0008-6223
Subject:
polycyclic aromatic hydrocarbons,   etc   ; carbon; crystallization; nanoparticles; particle size; pyrolysis; transmission electron microscopy;     Show all 7 Subjects
Abstract:
... In the pyrolysis of different hydrocarbon/carbon suboxid fuels formation of carbon particles with the special view to their structures was examined. For this, the following three very different pyrolysis systems were investigated experimentally i) a pyrolysis reactor, ii) a shock tube and iii) a plasma reactor with respect to the influence of varying reaction parameters on the carbonaceous nanopar ...
DOI:
10.1016/j.carbon.2019.02.034

10. Assessment of PM2.5 and PAH content in PM2.5 emitted from mobile source gasoline-fueled vehicles in concomitant with the vehicle model and mileages

Author:
Lin, Yuan-Chung; Li, Ya-Ching; Shangdiar, Sumarlin; Chou, Feng-Chih; Sheu, Yih-Terng; Cheng, Pei-Cheng
Source:
Chemosphere 2019 v.226 pp. 502-508
ISSN:
0045-6535
Subject:
polycyclic aromatic hydrocarbons,   etc   ; gas emissions; gas engines; gasoline; models; particulates; toxicity; urban population;     Show all 8 Subjects
Abstract:
... This study investigates the PM2.5 emission and analyses the PAHs content in PM2.5 emitted from gasoline-fueled vehicles. Outflow from the vehicles appear to be the ultimate source of PAHs in metro urban communities since the emission from gasoline vehicle increases the wellbeing hazard due to contiguity of exposure to gasoline exhaust. In this study, fifteen vehicles were randomly taken for sampli ...
DOI:
10.1016/j.chemosphere.2019.03.137

11. Effect of various chemical oxidation reagents on soil indigenous microbial diversity in remediation of soil contaminated by PAHs

Author:
Liao, Xiaoyong; Wu, Zeying; Li, You; Cao, Hongying; Su, Chunming
Source:
Chemosphere 2019 v.226 pp. 483-491
ISSN:
0045-6535
Subject:
polycyclic aromatic hydrocarbons,   etc   ; Pseudomonas; bioremediation; coal; microorganisms; oxidants; oxidation; polluted soils; potassium permanganate; total organic carbon;     Show all 10 Subjects
Abstract:
... Chemical oxidation is a promising pretreatment step coupled with bioremediation for removal of polycyclic aromatic hydrocarbons (PAHs). The effectiveness of Fenton, modified Fenton, potassium permanganate and activated persulfate oxidation treatments on the real contaminated soils collected from a coal gas plant (263.6 ± 73.3 mg kg−1 of the Σ16 PAHs) and a coking plant (385.2 ± 39.6 mg kg−1 of the ...
DOI:
10.1016/j.chemosphere.2019.03.126

12. Effects of asphalt source and mixing temperature on the generated asphalt fumes

Author:
Mo, Shicong; Wang, Yuhong; Xiong, Feng; Ai, Chunjin
Source:
Journal of hazardous materials 2019 v.371 pp. 342-351
ISSN:
0304-3894
Subject:
polycyclic aromatic hydrocarbons,   etc   ; bitumen; laboratory experimentation; mixing; occupational health and safety; particulates; pavements; risk assessment; temperature;     Show all 9 Subjects
Abstract:
... Asphalt fumes generated in pavement construction have been extensively studied from the perspective of occupational health. In this paper, they are examined from the perspective of material and construction. Asphalt binders from different sources were used to create standard mixtures. An asphalt fume generation and collection system was designed and built for generating fumes at simulated construc ...
DOI:
10.1016/j.jhazmat.2019.03.025

13. Emission behaviors of nitro- and oxy-polycyclic aromatic hydrocarbons during pyrolytic disposal of electronic wastes

Author:
Huang, HuiJing; Cai, ChuanYang; Yu, ShuangYu; Li, XinYue; Liu, Yu; Tao, Shu; Liu, WenXin
Source:
Chemosphere 2019 v.222 pp. 267-274
ISSN:
0045-6535
Subject:
polycyclic aromatic hydrocarbons,   etc   ; electronic wastes; emissions factor; molecular weight; particle size distribution; pyrolysis; temperature;     Show all 7 Subjects
Abstract:
... Emission factors (EFs) of polycyclic aromatic hydrocarbon (PAH) derivatives (12 nitro-PAHs and 4 oxy-PAHs) during the pyrolysis of two types of electronic waste (E-waste) were measured. Compositional profile, particle size distribution, gas-particle partitioning, correlations with precursor species and influences of pyrolytic temperature were investigated. The derivative products were dominated by ...
DOI:
10.1016/j.chemosphere.2019.01.125

14. Extremely small amounts of B[a]P residues remobilised in long-term contaminated soils: A strong case for greater focus on readily available and not total-extractable fractions in risk assessment

Author:
Umeh, Anthony C.; Duan, Luchun; Naidu, Ravi; Semple, Kirk T.
Source:
Journal of hazardous materials 2019 v.368 pp. 72-80
ISSN:
0304-3894
Subject:
polycyclic aromatic hydrocarbons,   etc   ; acetone; butanol; environmental health; methylene chloride; polluted soils; risk assessment; saponification; solvents;     Show all 9 Subjects
Abstract:
... There is a lack of understanding about the potential for remobilisation of polycyclic aromatic hydrocarbons (PAHs) residues in soils, specifically after the removal of readily available fractions, and the likelihood to cause harm to human and environmental health. Sequential solvent extractions, using butanol (BuOH), dichloromethane/acetone, and methanolic saponification were used to investigate t ...
DOI:
10.1016/j.jhazmat.2019.01.030

15. Distribution, source, and ecological risk assessment of PAHs among size and density fractions in contaminated sediments from the Yellow River of Henan section

Author:
Xi, Nannan; Guo, Wei; Feng, Jinglan; Liu, Shuhui; Sun, Jianhui
Source:
Environmental forensics 2019 v.20 no.2 pp. 171-181
ISSN:
1527-5930
Subject:
polycyclic aromatic hydrocarbons,   etc   ; environmental assessment; particle size; risk assessment; sediment contamination; sediments; toxicity; China; Yellow River;     Show all 9 Subjects
Abstract:
... This study investigated particle size and density distributions of polycyclic aromatic hydrocarbons (PAHs) in two surface sediments (JZ and KF), collected from the Yellow River of Henan section, China. The concentrations of Σ₁₅PAHs ranged from 35.6 to 45862 ng g⁻¹ dry wt, which were greatly elevated in coarse particles and low-density fractions. The Σ₁₅PAHs concentrations in low-density fractions ...
DOI:
10.1080/15275922.2019.1597778

16. Large-pore ordered mesoporous carbon as solid-phase microextraction coating for analysis of polycyclic aromatic hydrocarbons from aqueous media

Author:
Jiang, Hui; Hu, Xingru; Li, Yang; Qi, Junwen; Sun, Xiuyun; Wang, Lianjun; Li, Jiansheng
Source:
Talanta 2019 v.195 pp. 647-654
ISSN:
0039-9140
Subject:
polycyclic aromatic hydrocarbons,   etc   ; carbon; coatings; porosity; porous media; solid phase microextraction; surface area;     Show all 7 Subjects
Abstract:
... In this study, large pore ordered mesoporous carbon (LP-OMC) material was first applied as solid-phase microextraction (SPME) coating for the extraction of polycyclic aromatic hydrocarbons (PAHs) from aqueous media. The LP-OMC SPME fiber was prepared via the dip-coating method in-combination with evaporation-induced self-assembly (EISA) approach. The LP-OMC coating material possessed large specifi ...
DOI:
10.1016/j.talanta.2018.11.090

17. Catalytic pyrolysis of lignin in a cascade dual-catalyst system of modified red mud and HZSM-5 for aromatic hydrocarbon production

Author:
Wang, Shaoqing; Li, Zhihe; Bai, Xueyuan; Yi, Weiming; Fu, Peng
Source:
Bioresource technology 2019 v.278 pp. 66-72
ISSN:
0960-8524
Subject:
polycyclic aromatic hydrocarbons,   etc   ; biofuels; catalysts; environmental impact; lignin; pyrolysis; temperature; wastes;     Show all 8 Subjects
Abstract:
... Catalytic pyrolysis of lignin over a dual-catalyst system of modified red mud and HZSM-5 was carried out in a bench-scale micro-reactor. Effects of pyrolysis temperature, modified red mud to HZSM-5 ratio, catalysts to lignin ratio on the yield of products and selectivity of aromatic hydrocarbons were investigated. Results indicated that 550 °C was the optimal pyrolysis temperature with the maximal ...
DOI:
10.1016/j.biortech.2019.01.037

18. Comparison of extraction techniques for polycyclic aromatic hydrocarbons from lichen biomonitors

Author:
Van der Wat, Leandri; Forbes, Patricia B. C.
Source:
Environmental science and pollution research international 2019 v.26 no.11 pp. 11179-11190
ISSN:
0944-1344
Subject:
polycyclic aromatic hydrocarbons,   etc   ; energy; indicator species; lichens; microwave treatment; solvents; ultrasonic treatment;     Show all 7 Subjects
Abstract:
... Lichens are useful biomonitors for atmospheric polycyclic aromatic hydrocarbons (PAHs). Different sample preparation techniques were explored in this regard, including ultrasound-assisted solvent extraction, microwave-assisted extraction, Soxhlet, and the quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique. It was found that a QuEChERS technique using hexane:acetone (1:1, v/v), ne ...
DOI:
10.1007/s11356-019-04587-3

19. Different distribution of polycyclic aromatic hydrocarbons (PAHs) between Sphagnum and Ledum peat from an ombrotrophic bog in Northeast China

Author:
Wang, Zucheng; Li, Hongkai; Liu, Shasha
Source:
Journal of soils and sediments 2019 v.19 no.4 pp. 1735-1744
ISSN:
1439-0108
Subject:
polycyclic aromatic hydrocarbons,   etc   ; Ledum; Sphagnum; adsorption; bogs; cesium; peat; peatlands; radionuclides; sediments; China;     Show all 11 Subjects
Abstract:
... PURPOSE: The aims of this study are to investigate historical PAH deposition through the analysis of PAHs in bulk peat cores and reveal the different distribution of PAHs in Sphagnum and Ledum peat from peat cores. MATERIALS AND METHODS: Peat cores from Jingjiang peatland are collected, and Sphagnum peat samples are manually separated from bulk peat. The remaining bulk peat samples are defined as ...
DOI:
10.1007/s11368-018-2178-x

20. Effects of air/fuel ratio and ozone aging on physicochemical properties and oxidative potential of soot particles

Author:
Zhu, Jiali; Chen, Yueyue; Shang, Jing; Zhu, Tong
Source:
Chemosphere 2019 v.220 pp. 883-891
ISSN:
0045-6535
Subject:
polycyclic aromatic hydrocarbons,   etc   ; air; dithiothreitol; fuel combustion; fuels; organic carbon; ozone; soot; water solubility;     Show all 9 Subjects
Abstract:
... Fuel combustion conditions and atmospheric aging processes can affect the physicochemical properties of soot particles, which further change the oxidative potential (OP) of soot. In this study, we generated two soot samples under higher and lower air/fuel ratio (A/F) conditions, and further treated them with ozone (O3) at a level similar to that in the polluted atmosphere. The physicochemical prop ...
DOI:
10.1016/j.chemosphere.2018.12.107