Category: 191-07-1

Wang, Ziwei published the artcileEstimating the deposition of polycyclic aromatic hydrocarbons in human airways: The role of particle size, Category: catalysis-chemistry, the publication is Atmospheric Pollution Research (2022), 13(7), 101461, database is CAplus.

Most previous studies used atm. concentrations of polycyclic aromatic hydrocarbons (PAHs) to estimate the risk of exposure via inhalation, but neglected the disparities in the effects of particle size. In this study, an extensive literature search retrieved data from 35 cities on atm. PAHs and particle size distributions, and a multiple-path particle dosimetry model was used to simulate the PAH deposition in human airways. The results revealed that the median concentration of total PAHs was 38 (range, 0.6-2074.2) ng/m³, while the median concentration of benzo(a)pyrene equivalent (B[a]Peq) was 11 ng/m³. Together with exposure to congener-specific PAHs, the median deposited concentrations of total PAHs or B[a]Peq were the highest in particulate matter (PM) with diameters of 1-2.5 ¦Ìm, followed by > 1 ¦Ìm and coarse PM, which can be explained by the general increase in proportions of high mol. weight PAHs with decreasing PM size. While the deposited PAHs were dominated by 3-5 rings PAHs, the deposited B[a]Peq was concentrated in 5-ring. Moreover, although differences in the contributions of the ring number between deposited and ambient PAHs were negligible, the contributions of fine PM were 11.9% and 9.5% greater for deposited PAHs and B[a]Peq, resp. These results indicate that the risk of exposure to PAHs attached to fine PM is underestimated previously.

Atmospheric Pollution Research published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C6H12Br2, Category: catalysis-chemistry.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Akhmetov, Vladimir published the artcileAcenaphthenoannulation Induced by the Dual Lewis Acidity of Alumina, Category: catalysis-chemistry, the publication is Chemistry – A European Journal (2022), 28(31), e202200584, database is CAplus and MEDLINE.

Authors have discovered a dual (i. e., soft and hard) Lewis acidity of alumina that enables rapid one-pot ¦Ð-extension through the activation of terminal alkynes followed by C-F activation. The tandem reaction introduces an acenaphthene fragment – an essential moiety of geodesic polyarenes. This reaction provides quick access to elusive non-alternant polyarenes such as ¦Ð-extended buckybowls and helicenes through three-point annulation of the 1-(2-ethynyl-6-fluorophenyl)naphthalene moiety. The versatility of the developed method was demonstrated by the synthesis of unprecedented structural fragments of elusive geodesic graphene nanoribbons.

Chemistry – A European Journal published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C24H12, Category: catalysis-chemistry.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Li, Xinling published the artcileSize-fractionated nonpolar organic compounds of traffic aerosol emissions in a highway tunnel, Related Products of catalysis-chemistry, the publication is Environmental Pollution (Oxford, United Kingdom) (2022), 118501, database is CAplus and MEDLINE.

Size-fractionated aerosol samples (PM0.25, PM0.25-1, PM1-2.5, and PM2.5-10) were collected in a highway tunnel in Shanghai, China. The concentrations of nonpolar organic compounds (NPOCs), i.e., n-alkanes, polycyclic aromatic hydrocarbons (PAHs) and hopanes in the aerosol samples at the tunnel inlet and outlet, emission factors (EFs) of individual NPOCs in PM10, and EFs of size-fractionated individual NPOCs were analyzed comprehensively. NPOC concentrations in this tunnel were lower than the earlier tunnel results, which might be attributed to the tunnel configuration effect on the pollution dilution along the tunnel, in addition to the improvement of engine technol. and fuel quality during past decades. n-Alkane homologs for C14-C35 exhibited a smooth hump-like distribution pattern with the most abundance at C22 and 1-2 carbon number shifts of Cmax in comparison to those in other tunnels due to different fleet and fuel compositions The most abundant PAHs from diesel (e.g., Nap, Phe, Flu and Pyr) and gasoline (e.g., BghiF, BbkF, BeP, DBA and BghiP) vehicle emissions presented concentration increases of 1.8-5.8 times from the tunnel inlet to outlet. The individual n-alkane and PAH distributions exhibited obvious size dependence, while it was expected that the relative abundances and homolog distributions of hopanes were very similar for different size stages. Several diagnostic ratios, e.g., fossil/plant n-alkanes and LMW/HMW PAHs, were evidently size dependent, indicating different sources of size-fractionated n-alkanes and PAHs.

Environmental Pollution (Oxford, United Kingdom) published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C24H12, Related Products of catalysis-chemistry.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Elgengehi, Sara M. published the artcileAdsorption of chlorine oxyanions, as water disinfectant by-products, on graphene flakes: A quantum chemical investigation, Quality Control of 191-07-1, the publication is Surfaces and Interfaces (2022), 101601, database is CAplus.

Chlorine oxyanions namely: hypochlorite ClO^–, chlorite ClO^–₂, chlorate ClO^–₃, and perchlorate ClO^–₄, are considered to be harmful for public health since they are disinfectant byproducts and are usually found in the disinfection process of drinking water treatment plants (DWTPs). The removal of these oxyanions is, therefore, an important demand. In the current work, the adsorption of chlorine oxyanions on some graphene flakes (Gr) such as coronene (C₂₄H₁₂), circumcoronene (C₅H₁₈), and circumcircumcoronene (C₉₆H₂₄), has been theor. investigated. Favorable adequate (anion-¦Ð) interaction between the chlorine oxyanions and the electron-rich graphene flakes have been elucidated, where the stabilization largely originates from attractive electrostatic and dispersion effects. The exponential increase in the attractive electrostatic and dispersion components of the adsorption energies is found to be, in part, a consequence of a charge transfer contribution from the oxygen lone pairs of electrons of oxyanions (donors) to the low-lying ¦Ð*-orbitals of graphene flakes (acceptors). This finding means that the favorable anion-¦Ð interaction between a chlorine oxyanion and a graphene surface is not purely non-covalent.

Surfaces and Interfaces published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C24H12, Quality Control of 191-07-1.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Wang, Lizhi published the artcileOn-site measured emission factors of polycyclic aromatic hydrocarbons for different types of marine vessels, Safety of Coronene, the publication is Environmental Pollution (Oxford, United Kingdom) (2022), 118782, database is CAplus and MEDLINE.

A portable emission sampling system was used to perform on-site measurements of the emission factors (EFs; quantities of pollutants emitted per unit of energy consumed) of 29 polycyclic aromatic hydrocarbons (PAHs) for five types of marine vessels using light diesel in Hainan Province, China. Both gaseous- and particulate-phase PAHs from vessel emissions were sampled and measured using gas chromatog. coupled with mass spectrometry (GC-MS), and the PAH EFs were calculated based on the carbon mass balance method. The average EFs of gaseous- and particulate-phase PAHs were 6.2 ¡À 7.8 and 17 ¡À 26 mg/kg, with naphthalene (NAP) and phenanthrene (PHE) dominating the gaseous- and particulate-phase PAH emissions, resp. Among the five types of vessels, the EFs for small fishing boats were significantly higher than those for other types of vessels, and the lowest EFs were found for tug boats. Composition profiles and typical isomer ratios of PAHs were calculated for five types of vessels. Particulate-phase PAHs accounted for 63 ¡À 16% of the total emissions of 29 PAH species, and the particulate/gaseous-phase partitioning of PAHs was dominated by organic carbon (OC) absorption rather than black carbon (BC) adsorption. Emission factors of PAHs under different activity conditions were measured and calculated, and relatively higher EFs were found in the maneuvering mode for medium fishing boats and in the operating mode for engineering vessels. No significant differences were found among the PAH composition profiles under different activity conditions.

Environmental Pollution (Oxford, United Kingdom) published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C10H10O6, Safety of Coronene.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Ekner, Holly published the artcileDetermination of polycyclic aromatic hydrocarbons in commercial olive oils by HPLC/GC/MS – Occurrence, composition and sources, Synthetic Route of 191-07-1, the publication is Food Control (2022), 108528, database is CAplus.

Polycyclic aromatic hydrocarbons (PAHs) are a large class of organic compounds produced from incomplete combustion. Many PAHs are mutagenic and some are carcinogenic and pose a health risk to humans. Dietary intake of PAHs is a major route of exposure, where fats and edible oils are important contributors to overall dietary PAH exposure. Composed of hundreds of individual compounds as a complex mixture, only 16 PAHs are typically monitored in food and the environment. In this present study we analyzed 16 com. olive oil samples from different countries of origin and type (virgin or refined oil) for their content of 45 PAHs using a high-performance liquid chromatograph coupled to a gas chromatograph with a mass spectrometric detector. The content of the 45 PAHs varied between 9.17 and 94.7¦Ìg/kg (median: 30.1¦Ìg/kg) in the different olive oil samples. Only one sample didn’t meet the regulatory threshold levels for PAHs. The compositional profile of PAHs across the olive oil samples showed a high abundance of PAHs of lower mol. weights, and a large contribution of alkylated PAHs regardless of olive oil type. Direct contact with diesel exhaust emissions from mech. harvesters has previously shown to affect PAH levels in olive oils. Using diagnostic PAH ratios, biomass/coal combustion and/or petroleum/fossil fuel combustion were indicated as important sources. Source apportionment by Pos. Matrix Factorization revealed diesel exhaust emission and biomass combustion as the two major sources of PAHs followed by traffic emissions. This suggests that air quality may have a considerable impact on pollution levels in olive oils and thus indirectly affect dietary exposure.

Food Control published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C24H12, Synthetic Route of 191-07-1.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Nakagawa, Takeshi published the artcilePiezochromic luminescence of dicoronylene: Key for revealing hidden Raman modes at high pressure, HPLC of Formula: 191-07-1, the publication is Carbon (2022), 563-569, database is CAplus.

Mol. crystals of dicoronylene (C₄₈H₂₀), a member of very large polycyclic aromatic hydrocarbons (PAHs), exhibits strong red fluorescence under ambient conditions. This strong fluorescence induced by visible light excitation obscures entire Raman spectrum of dicoronylene. The authors employed in-situ high-pressure luminescence spectroscopy to observe a reversible piezochromic effect, in which the fluorescence exhibits a drastic red shift with a rapid quenching of intensity. At >4 GPa, under red shifted and reduced fluorescence, hidden Raman modes are observed with 532 nm green laser at ¡Ü20 GPa. The application of pressure can finely tune the fluorescence of dicoronylene, allowing the observation of the Raman spectrum with an appropriate laser wavelength and dicoronylene has high chem. stability among PAH mols. with multiple aromatic rings.

Carbon published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C24H12, HPLC of Formula: 191-07-1.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Veronesi, Stefano published the artcileMorphology and electronic properties of incipient soot by scanning tunneling microscopy and spectroscopy, Application of Coronene, the publication is Combustion and Flame, database is CAplus.

Soot nucleation is one of the most complex and debated steps of the soot formation process in combustion. In this work, we used scanning tunneling microscopy (STM) and spectroscopy (STS) to probe morphol. and electronic properties of incipient soot particles formed right behind the flame front of a lightly sooting laminar premixed flame of ethylene and air. Particles were thermophoretically sampled on an atomically flat gold film on a mica substrate. High-resolution STM images of incipient soot particles were obtained for the first time showing the morphol. of sub-5 nm incipient soot particles. High-resolution single-particle spectroscopic properties were measured confirming the semiconductor behavior of incipient soot particles with an electronic band gap ranging from 1.5 to 2 eV, consistent with earlier optical and spectroscopic observations.

Combustion and Flame published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C20H40O2, Application of Coronene.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Torres, Alejandro published the artcileElectrocatalytic Behavior of Tetrathiafulvalene (TTF) and Extended Tetrathiafulvalene (exTTF) [FeFe] Hydrogenase Mimics, Product Details of C24H12, the publication is ACS Organic & Inorganic Au (2022), 2(1), 23-33, database is CAplus.

TTF- and exTTF-containing [(¦Ì-S₂)Fe₂(CO)₆] complexes have been prepared by the photochem. reaction of TTF or exTTF and [(¦Ì-S₂)Fe₂(CO)₆]. These complexes are able to interact with PAHs. In the absence of air and in acid media an electrocatalytic dihydrogen evolution reaction (HER) occurs, similarly to analogous [(¦Ì-S₂)Fe₂(CO)₆] complexes. However, in the presence of air, the TTF and exTTF organic moieties strongly influence the electrochem. of these systems. The reported data may be valuable in the design of [FeFe] hydrogenase mimics able to combine the HER properties of the [FeFe] cores with the unique TTF properties.

ACS Organic & Inorganic Au published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C18H34N4O5S, Product Details of C24H12.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Zhou, Yuxin published the artcileMolecular Dynamics Study on the Condensation of PAH Molecules on Quasi Soot Surfaces, Synthetic Route of 191-07-1, the publication is Journal of Physical Chemistry A (2022), 126(4), 630-639, database is CAplus and MEDLINE.

In this paper, the condensation efficiency of polycyclic aromatic hydrocarbon (PAH) mols. up to coronene, from 500 to 2000 K, is calculated based on hundreds of collisions between a PAH mol. and the quasi soot surface, which is composed of stacked coronene mols. with periodic boundary conditions, using mol. dynamics simulations. The results show that the condensation efficiency increases with the PAH mol. mass but decreases as the temperature increases, following a Gaussian function. Meanwhile, when the presence of aliphatic chains on soot particle surfaces is considered, the condensation efficiency can be lowered by up to 40%, being affected more significantly at higher temperatures A condensation efficiency model is thus proposed from the mol. trajectories. Finally, when this newly proposed PAH condensation efficiency model is adopted, better agreement with the experiments is achieved in predicting soot volume fractions of an ethylene/oxygen/nitrogen mixture in a tandem jet-stirred reactor and a plug-flow reactor.

Journal of Physical Chemistry A published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C18H10, Synthetic Route of 191-07-1.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia