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Degradation of the highly complex polycyclic aromatic hydrocarbon coronene by the halophilic bacterial strain Halomonas caseinilytica, 10SCRN4D

Okeyode Ajibola H., Al-Thukair Assad, Chanbasha Basheer, Nazal Mazen K., Afuecheta Emmanuel, Musa Musa M., Algarni Shahad, Nzila Alexis

Archives of Environmental Protection

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2023

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Vol. 49, no 3

78--86

EN

Polycyclic aromatic hydrocarbons (PAHs) are significant pollutants found in petroleum products. There is ample literature on the biodegradation of PAHs containing less than five rings, but little has been done on those with more than five rings. Coronene (CRN), a seven-ring-containing PAH, has only been shown to be degraded by one bacterial strain. In this study, a bacterial strain 10SCRN4D was isolated through enrichment in the presence of CRN and 10% NaCl (w/v). Analysis of the 16S rRNA gene identified the strain as Halomonas caseinilytica. The strain was able to degrade CRN in media containing 16.5–165 μM CRN with a doubling time of 9–16 hours and grew in a wide range of salinity (0.5–10%, w/v) and temperature (30–50°C) with optimum conditions of pH 7, salinity 0.5%–10% (w/v), and temperature 37°C. Over 20 days, almost 35% of 16.5 μM CRN was degraded, reaching 76% degradation after 80 days as measured by gas chromatography. The strain was also able to degrade smaller molecular weight PAHs such as benzo[a]pyrene, pyrene, and phenanthrene. This is the first report of Halomonas caseinilytica degrading CRN as the sole carbon source in high salinity, and thus highlights the potential of this strain in bioremediation.

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Functionalization of the Si(1 1 1) 7 × 7 substrate with coronene molecules using simple molecular source

Przychodnia M., Czajka R., Koczorowski W.

Materials Science Poland

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2018

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Vol. 36, No. 1

86--92

EN

The present paper aims at describing a source designed and constructed to generate an organic molecular beam under ultrahigh vacuum conditions. The presented construction solution of the evaporation source allows for independent deposition of three different kinds of molecules. The probability of molecules fragmentation is minimized by using a thermocouple being in contact with a molecular crucible, which enables precise temperature control. In addition, cleanness and molecular beam density are monitored using a quadrupole mass spectrometer and quartz microbalance, respectively. The operational parameters of the molecular source are optimized and deposition rates are measured for the coronene molecule in the sublimation temperature range between 430 K and 460 K. The analysis of scanning tunneling microscope images of the Si(1 1 1) 7 × 7 substrate covered with the sub-monolayer of coronene molecules and comparison with previously published data has been used for verification of the molecular source operation.

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Schultz and Modified Schultz Polynomials of Coronene Polycyclic Aromatic Hydrocarbons

Farahani M. R.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 13, iss. 1

1-10

EN

Let G = (V;E) be a simple connected graph. The sets of vertices and edges of G are denoted by V = V(G) and E = E(G), respectively. In such a simple molecular graph, vertices represent atoms and edges represent bonds. The distance between the vertices u and v in V(G) of graph G is the number of edges in a shortest path connecting them, we denote by d(u,v). In graph theory, we have many invariant polynomials for a graph G. In this research, we computing the Schultz polynomial, Modified Schultz polynomial, Hosoya polynomial and their topological indices of a Hydrocarbon molecule, that we call “Coronene Polycyclic Aromatic Hydrocarbons”.

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DC conductivity in coronene thin films

Tkaczyk S. W., Świątek J.

Scientific Bulletin. Physics / Lodz University of Technology

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2006

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Vol. 26

93-98

EN

This paper contains the results of the investigations of coronene (C24H12) polycrystalline thin films. The purpose of the investigations was finding the mechanisms of DC conducivity in polycrystalline coronene structures. The charge transport is controlled by traps. The determined values of the activation energy are in the range from 0.01 to 0.05 eV in temperature rang 30-325 K.

PL

Praca zawiera wyniki badań cienkich polikrystalicznych warstw koronenu (C24H12). Celem przeprowadzonych badań było poznanie mechanizmów przewodnictwa stałoprądowego w polikrystalicznych strukturach koronenu. Pomiary przeprowadzono dla warstw o grubości od 0,3-1,1 µm. Wartość napięć polaryzujących próbkę wahała się w granicach od 0 V do 40 V, a zmiany temperatur dla których prowadzono badania zawierały się od 20 K do 325 K. Transport ładunku elektrycznego przez objętość materiału jest kontrolowany przez stany pułapkowe. Wyznaczona energia aktywacji zawierała się w granicach od 0,01 do 0,05 eV, dla temperatur od 30 K - 325 K.