scholarly journals Oxidation of Polynuclear Aromatic Hydrocarbons using Ruthenium-Ion-Catalyzed Oxidation: The Role of Aromatic Ring Number in Reaction Kinetics and Product Distribution

2017 ◽  
Vol 24 (3) ◽  
pp. 655-662 ◽  
Author(s):  
Ewa Nowicka ◽  
Tomos J. Clarke ◽  
Meenakshisundaram Sankar ◽  
Robert L. Jenkins ◽  
David W. Knight ◽  
...  
Keyword(s):  
Reaction Kinetics ◽  
Aromatic Ring ◽  
Aromatic Hydrocarbons ◽  
Product Distribution ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Ring Number ◽  
Catalyzed Oxidation

Role of Imperfections in the Regiospecific Photodimerization of some Polynuclear Aromatic Hydrocarbons in the Solid State

1976 ◽  
Vol 32 (1) ◽  
pp. 107-110
Author(s):  
J. P. Desvergne ◽  
H. Bouas-laurent ◽  
R. Lapouyade ◽  
J. M. Thomas ◽  
J. Gaultier ◽  
...  
Keyword(s):  
Solid State ◽  
Aromatic Hydrocarbons ◽  
Polynuclear Aromatic Hydrocarbons

scholarly journals Role of methyl group number on SOA formation from aromatic hydrocarbons photooxidation under low NO<sub><i>x</i></sub> conditions

2015 ◽  
Vol 15 (21) ◽  
pp. 31153-31196 ◽  
Author(s):  
L. Li ◽  
P. Tang ◽  
S. Nakao ◽  
C.-L. Chen ◽  
D. R. Cocker III
Keyword(s):  
Aromatic Hydrocarbon ◽  
Aromatic Ring ◽  
Aromatic Hydrocarbons ◽  
Methyl Groups ◽  
Methyl Group ◽  
Group Number ◽  
The Impact ◽  
First Time ◽  
Linear Trends

Abstract. Substitution of methyl groups onto the aromatic ring determines the SOA formation from the aromatic hydrocarbon precursor. This study links the number of methyl groups on the aromatic ring to SOA formation from aromatic hydrocarbons photooxidation under low NOx conditions (HC / NO > 10 ppb C : ppb). Aromatic hydrocarbons with increasing numbers of methyl groups are systematically studied. SOA formation from pentamethylbenzene and hexamethylbenzene are reported for the first time. A decreasing SOA yield with increasing number of methyl groups is observed. Linear trends are found in both f44 vs. f43 and O / C vs. H / C for SOA from aromatic hydrocarbons with zero to six methyl groups. An SOA oxidation state predictive method based on benzene is used to examine the effect of added methyl groups on aromatic oxidation under low NOx conditions. Further, the impact of methyl group number on density and volatility of SOA from aromatic hydrocarbons is explored. Finally, a mechanism for methyl group impact on SOA formation is suggested. Overall, this work suggests as more methyl groups are attached on the aromatic ring, SOA products from these aromatic hydrocarbons become less oxidized per mass/carbon.

scholarly journals Bacteria Belonging to the Genus Cycloclasticus Play a Primary Role in the Degradation of Aromatic Hydrocarbons Released in a Marine Environment

2002 ◽  
Vol 68 (11) ◽  
pp. 5625-5633 ◽  
Author(s):  
Yuki Kasai ◽  
Hideo Kishira ◽  
Shigeaki Harayama
Keyword(s):  
Crude Oil ◽  
Marine Environment ◽  
Aromatic Hydrocarbons ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Aerobic Degradation ◽  
Primary Role ◽  
Bacterial Group ◽  
Nitrogen And Phosphorus ◽  
Gravel Layer

ABSTRACT To identify the bacteria that play a major role in the aerobic degradation of petroleum polynuclear aromatic hydrocarbons (PAHs) in a marine environment, bacteria were enriched from seawater by using 2-methylnaphthalene, phenanthrene, or anthracene as a carbon and energy source. We found that members of the genus Cycloclasticus became predominant in the enrichment cultures. The Cycloclasticus strains isolated in this study could grow on crude oil and degraded PAH components of crude oil, including unsubstituted and substituted naphthalenes, dibenzothiophenes, phenanthrenes, and fluorenes. To deduce the role of Cycloclasticus strains in a coastal zone oil spill, propagation of this bacterial group on oil-coated grains of gravel immersed in seawater was investigated in beach-simulating tanks that were 1 m wide by 1.5 m long by 1 m high. The tanks were two-thirds filled with gravel, and seawater was continuously introduced into the tanks; the water level was varied between 30 cm above and 30 cm below the surface of the gravel layer to simulate a 12-h tidal cycle. The number of Cycloclasticus cells associated with the grains was on the order of 103 cells/g of grains before crude oil was added to the tanks and increased to 3 × 106 cells/g of grains after crude oil was added. The number increased further after 14 days to 108 cells/g of grains when nitrogen and phosphorus fertilizers were added, while the number remained 3 × 106 cells/g of grains when no fertilizers were added. PAH degradation proceeded parallel with the growth of Cycloclasticus cells on the surfaces of the oil-polluted grains of gravel. These observations suggest that bacteria belonging to the genus Cycloclasticus play an important role in the degradation of petroleum PAHs in a marine environment.

Polycyclic aromatic hydrocarbon (PAH) formation from benzyl radicals: a reaction kinetics study

2016 ◽  
Vol 18 (11) ◽  
pp. 8120-8131 ◽  
Author(s):  
Sourab Sinha ◽  
Abhijeet Raj
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
High Temperature ◽  
Polycyclic Aromatic Hydrocarbon ◽  
Aromatic Hydrocarbon ◽  
Reaction Kinetics ◽  
Aromatic Hydrocarbons ◽  
Kinetics Study ◽  
Benzyl Radicals ◽  
Polycyclic Aromatic

The role of resonantly stabilized benzyl radicals in the formation of polycyclic aromatic hydrocarbons (phenanthrene and anthracene) in high-temperature flame environments has been explored.

The role of aromatic ring number in phenolic compound-conjugated chitosan injectables for sustained therapeutic antiglaucoma efficacy

2020 ◽  
Vol 231 ◽  
pp. 115770 ◽  
Author(s):  
Duc Dung Nguyen ◽  
Li-Jyuan Luo ◽  
Shingjiang Jessie Lue ◽  
Jui-Yang Lai
Keyword(s):  
Phenolic Compound ◽  
Aromatic Ring ◽  
Ring Number

scholarly journals Role of methyl group number on SOA formation from monocyclic aromatic hydrocarbons photooxidation under low-NO<sub><i>x</i></sub> conditions

2016 ◽  
Vol 16 (4) ◽  
pp. 2255-2272 ◽  
Author(s):  
L. Li ◽  
P. Tang ◽  
S. Nakao ◽  
C.-L. Chen ◽  
D. R. Cocker III
Keyword(s):  
Chemical Composition ◽  
Aromatic Ring ◽  
Aromatic Hydrocarbons ◽  
Methyl Groups ◽  
Methyl Group ◽  
Monocyclic Aromatic Hydrocarbons ◽  
Group Number ◽  
The Impact ◽  
First Time

Abstract. Substitution of methyl groups onto the aromatic ring determines the secondary organic aerosol (SOA) formation from the monocyclic aromatic hydrocarbon precursor (SOA yield and chemical composition). This study links the number of methyl groups on the aromatic ring to SOA formation from monocyclic aromatic hydrocarbons photooxidation under low-NOx conditions (HC/NO  >  10 ppbC : ppb). Monocyclic aromatic hydrocarbons with increasing numbers of methyl groups are systematically studied. SOA formation from pentamethylbenzene and hexamethylbenzene are reported for the first time. A decreasing SOA yield with increasing number of methyl groups is observed. Linear trends are found in both f44 vs. f43 and O / C vs. H / C for SOA from monocyclic aromatic hydrocarbons with zero to six methyl groups. An SOA oxidation state predictive method based on benzene is used to examine the effect of added methyl groups on aromatic oxidation under low-NOx conditions. Further, the impact of methyl group number on density and volatility of SOA from monocyclic aromatic hydrocarbons is explored. Finally, a mechanism for methyl group impact on SOA formation is suggested. Overall, this work suggests that, as more methyl groups are attached on the aromatic ring, SOA products from these monocyclic aromatic hydrocarbons become less oxidized per mass/carbon on the basis of SOA yield or chemical composition.

scholarly journals Extractive Dearomatization of Naphthalane Oil Fraction with Ionic Liquid and -N-Methyl-2-Pyrrolidone

2015 ◽  
Vol 11 (6) ◽  
pp. 3622-3629
Author(s):  
Vagif М. Abbasov ◽  
Leylufer I. Aliyeva ◽  
Parvana A. Movsumova ◽  
Almaz M. Tagieva ◽  
Gultakin A. Najafova ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Spectral Analysis ◽  
Aromatic Hydrocarbons ◽  
Extraction Method ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Selective Treatment ◽  
Oil Fraction ◽  
Residual Amount ◽  
Therapeutic Properties

In the article are given an analysis of the results of researches carried out for the purpose of selective treatment of the Naphthalane oil fraction boiling at 260-3400C with ionic liquid (IL) -morfolinphormiate synthesized on the basis formic acid + morpholine and - N-methyl-2-pyrrolidon (N-MP) and  as an extractant. The aim is to remove poisonous components -  sulfur compounds and toxic carcinogenic polynuclear aromatic hydrocarbons in order to improve therapeutic properties of Naphthalane oil cut. For this purpose we have used extraction method. On the basis of the conducted researches the role of -N-methyl-2-pyrrolidone and IL-morpholinephormiatee in extraction conditions have been determined in selective treatment of Nafthalan oil, according to the results of spectral analysis residual amount of aromatic hydrocarbons decreased from 18.5% wt accordance to 2%, 1.5%. As well as the amount of sulphur decreased from 0.0354% to 0.010%,  0.011% and 0.019%.In the next stage the treated raffinates with N-methyl-2-pyrrolidone has been purified on silica. In a result amount of aromatic hydrocarbons drastically decrease to be 0.07% and 0.02%. As a result we aquire transparency and at the same time the percentage amount of aromatic hydrocarbons drastically decreased from 2% to 0,07%, 1.5%, to 0.02%. Raffinates obtained in a 2-4 stage dearomatization with N-MP and IL. Raffinate are measured on NMR, UV and IR spectral analysis.

scholarly journals Composition Studies on Tobacco. XXlll: Pyrolytic and Structural Investigations on the Polyphenol-amino Acid Pigments of Leaf

1966 ◽  
Vol 3 (6) ◽  
Author(s):  
O.T.O. T. Chortyk ◽  
W. S. Schlotzhauer ◽  
R. L. Stedman
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Chlorogenic Acid ◽  
Aromatic Hydrocarbons ◽  
Aromatic Compounds ◽  
Composition Studies ◽  
Aqueous Extraction ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Structural Investigations

AbstractThe complex polyphenolic pigments of Turkish tobacco have been pyrolyzed to determine their possible contribution to the formation of aromatic compounds, especially polynuclear aromatic hydrocarbons (PAH), of smoke. The dark brown pigments were initially obtained by a basic aqueous extraction of tobacco. Various hydrolytic procedures showed the presence of rutin, chlorogenic acid, and a series of amino acids; some information on the structure of these pigments is presented. The pyrolysis of the pigments was carried out at 850°C and the products were fractionated to reveal the presence of more than a dozen PAH. Addition of pigments to cigarettes gave an increase in the level of benzo[a]pyrene in the smoke. The possible role of the polyphenolic pigments as a source of PAH in smoke is discussed

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