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Prasad G Mahajan, G B Kolekar, Shivajirao R Patil
Polyvinyl pyrrolidone (PVP) crowned chrysene nanoparticles (CHYNPs) were prepared by using a reprecipitation method. Dynamic light scattering (DLS) and scanning electron microscope (SEM) studies indicate that the monodispersed spherical nanoparticles bear a negative charge on their surfaces. The bathochromic spectral shift in the UV-visible and fluorescence spectrum of CHYNPs from chrysene (CHY) in acetone solution supports the J- type aggregation of nanoparticles. The aggregation-induced enhanced emission of CHYNPs at 486 and 522 nm decreases by increasing the concentration of the Ca(2)(+) ion solution...
January 5, 2017: Luminescence: the Journal of Biological and Chemical Luminescence
Simone Alves da Silva, Geni Rodrigues Sampaio, Elizabeth Aparecida Ferraz da Silva Torres
Among the different food categories, the oils and fats are important sources of exposure to polycyclic aromatic hydrocarbons (PAHs), a group of organic chemical contaminants. The use of a validated method is essential to obtain reliable analytical results since the legislation establishes maximum limits in different foods. The objective of this study was to optimize and validate a method for the quantification of four PAHs [benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(a)pyrene] in vegetable oils...
April 15, 2017: Food Chemistry
Tzu-Ting Yang, Su-Chen Ho, Lu-Te Chuang, Hsiao-Chi Chuang, Ya-Ting Li, Jyun-Jie Wu
This study investigated the effects of particle-bound polycyclic aromatic hydrocarbons (PAHs) produced from burning three incense types on and their bioreactivity in the RAW 264.7 murine macrophage cell line. Gas chromatography/mass spectrometry was used to determine the levels of 16 identified PAHs. Macrophages were exposed to incense particle extracts at concentrations of 0, 3.125, 6.25, 12.5, 25, 50, and 100 μg/mL for 24 h. After exposure, cell viability and nitric oxide (NO) and inflammatory mediator [tumor necrosis factor (TNF)-α] production of the cells were examined...
January 2017: Environmental Pollution
Edu Inam, Felicia Ibanga, Joseph Essien
Using gas chromatography-mass spectrometry and an incremental lifetime cancer risks (ILCRs) assessment model, the bioaccumulation and cancer risk of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) in leafy vegetables (Vernonia amygdalina and Lasianthera africanum) grown in soils within an automobile repair complex environment in Uyo, Nigeria was studied. The total PAHs concentrations recorded for soils ranged from 0.02 to 1.77 mg/kg. The highest level of 1.77 mg/kg was recorded for soils from the main automobile repair complex (site 1)...
December 2016: Environmental Monitoring and Assessment
Amir Karton
Density functional theory (DFT) is the only quantum-chemical avenue for calculating thermochemical/kinetic properties of large polycyclic aromatic hydrocarbons (PAHs) such as graphene nanoflakes. Using CCSD(T)/CBS PAH isomerization energies, we find that all generalized gradient approximation (GGA) and meta GGA DFT functionals have severe difficulties in describing isomerization energies in PAHs. The poor performance of these functionals is demonstrated by the following root-mean-square deviations (RMSDs) obtained for a database of C14 H10 and C18 H12 isomerization energies...
March 5, 2017: Journal of Computational Chemistry
Yaacov Netanel Oded, Sergey Pogodin, Israel Agranat
Intramolecular Scholl reaction of 1-benzoylpyrene (1) gave 8H-dibenzo[def,qr]chrysen-8-one (2) and 11H-indeno[2,1-a]pyren-11-one (3) in a 1:2 ratio. The structures of 2 and 3 were determined, using (1)H NMR, (13)C NMR, and IR spectroscopies. A DFT B3LYP/6-311G(d,p) study of the reaction's arenium-cation mechanism of (E)-1 and (Z)-1 giving 2 and 3, respectively, indicated the reaction's regioselectivity and kinetic control. The analogous reaction of 1-(1'-naphthoyl)pyrene gave exclusively 13H-benz[4,5]indeno[2,1-a]pyren-13-one...
November 18, 2016: Journal of Organic Chemistry
Jinpu Jia, Chunjuan Bi, Xue Guo, Xueping Wang, Xiaoxiao Zhou, Zhenlou Chen
Road dusts and agricultural soil samples were collected from eight sites close to steel mills, chemical plants, and municipal solid waste incinerator in suburban Shanghai. Sixteen polycyclic aromatic hydrocarbons (PAHs) in the United States Environmental Protection Agency (US EPA) priority controlled list were analyzed quantitatively using GC-MS. The total PAH concentrations ranged from 0.79 to 6.2 μg g(-1) in road dust samples with a mean value of 2.38 μg g(-1) and 0.26 to 0.54 μg g(-1) in agricultural soils with an average of 0...
January 2017: Environmental Science and Pollution Research International
Naoto Suzuki, Takeshi Fujita, Konstantin Yu Amsharov, Junji Ichikawa
Selective synthesis of benzo[f]tetraphenes or benzo[g]chrysenes was achieved via aromatic C-F bond cleavage and unprecedented regioselective C-C bond formation depending upon the choice of aluminium reagents. On treatment with AlCl3, 2-(biphenyl-2-yl)-1-fluoronaphthalenes afforded exclusively benzo[f]tetraphenes via C-C bond formation on the carbon atom γ to the original position of the fluorine substituent. In contrast, α-selective C-C bond formation was promoted by treatment with γ-Al2O3 to give benzo[g]chrysenes...
October 7, 2016: Chemical Communications: Chem Comm
Olga Monago-Maraña, Rocío L Pérez, Graciela M Escandar, Arsenio Muñoz de la Peña, Teresa Galeano-Díaz
This work presents a strategy for quantitating polycyclic aromatic hydrocarbons (PAHs) in smoked paprika samples. For this, a liquid chromatographic method with fluorimetric detection (HPLC-FLD) was optimized. To resolve some interference co-eluting with the target analytes, the second-order multivariate curve resolution-alternating least-squares (MCR-ALS) algorithm has been employed combined with this liquid chromatographic method. Among the eight PAHs quantified (fluorene, phenanthrene, anthracene, pyrene, chrysene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[a]pyrene) by HPLC-FLD, only in the case of fluorene, pyrene, and benzo[b]fluoranthene was it necessary to apply the second-order algorithm for their resolution...
November 2, 2016: Journal of Agricultural and Food Chemistry
Wenfen Zhang, Yanhao Zhang, Qiong Jiang, Wenjie Zhao, Ajuan Yu, Hong Chang, Ximei Lu, Fuwei Xie, Baoxian Ye, Shusheng Zhang
To satisfy the requirement of simultaneous extraction and characterization of diverse kinds of multi-target analytes, the preparation, characterization and application of a novel tetraazacalix[2]arene[2]triazine (TCT) coated magnetic nanoparticular (TCT MNP) adsorbent are presented in this paper. TCT assembles two benzene rings and two triazines with nitrogen cross-bridging links, which exhibits a unique structural framework and versatile recognition features based on the multiple recognition sites. These include π electron stacking, charge transfer, hydrogen bonding and ion-exchange...
October 7, 2016: Analytical Chemistry
Laura Pereira Garcia, Fernanda M L Gomes, Silvia Tfouni, Eduardo Vicente, Geovana D Savi, Karolina Santos, Vildes M Scussel
A total of 13 polycyclic aromatic hydrocarbons (PAHs) were surveyed in dry whole soybeans (Glycine max L.) sold for human consumption. The analysed samples were commercialised in vegetarian shops and food stores in Southern Brazil regions. The determination of PAHs levels was carried out by high performance liquid chromatography (HPLC)with fluorescence detection. PAHs were present in 89.7% of the samples. Chrysene (Chy) and 5 methyl chrysene (5MeChy) were the main PAHs detected (76.9% and 71.8%, respectively) followed by dibenzo(ai)pyrene (DaiP), however in a much less percentage of samples (23...
October 6, 2016: Food Additives & Contaminants. Part B, Surveillance
Jyotilima Saikia, Puja Khare, Prasenjit Saikia, Binoy K Saikia
In the present investigation, the concentrations of polycyclic aromatic hydrocarbons (PAHs) associated with PM2.5, PM10 and dust particles emitted from two tea processing industrial units were studied that uses high-sulfur coal as their energy source. A total of 16 PAHs (viz. naphthalene (Nap), acenaphthene (Ace), acenaphthylene (Acen), phenanthrene (Phe), fluorene (Flu), anthracene (Ant), fluoranthene (Fluo), pyrene (Pyr), benz[a]anthracene (BaA), chrysene (Chry), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), dibenz[a,h]anthracene (DBahA), indeno[1,2,3-cd]pyrene (IP) and benzo[ghi]perylene (BghiP) were measured...
September 27, 2016: Environmental Geochemistry and Health
Ruiming Guo, Luqing Pan, Pengfei Lin, Lei Zheng
This study aimed to investigate the detoxification responses, damage effects and biotransformation in scallop Chlamys farreri exposed to benzo[a]pyrene (BaP) (0.1, 1μg/L), chrysene (CHR) (0.1, 1μg/L) and BaP+CHR (0.1+0.1, 1+1μg/L) for 15days. Results demonstrated that BaP and CHR concentration (BaP<CHR) in tissues increased rapidly in a time and dose effect. The mRNA expression of aryl hydrocarbon receptor (AhR), cytochrome P450 1A1 (CYP1A1), CYP1B1, multidrug resistance protein 1 (MRP1/ABCC1), breast cancer resistance protein (BCRP/ABCG2) and P-glycoprotein (P-gp) were induced especially in the mixtures of BaP and CHR...
January 2017: Comparative Biochemistry and Physiology. Toxicology & Pharmacology: CBP
Kin-Fai Ho, Chih-Cheng Chang, Linwei Tian, Chi-Sing Chan, Benjamin A Musa Bandowe, Ka-Hei Lui, Kang-Yun Lee, Kai-Jen Chuang, Chien-Ying Liu, Zhi Ning, Hsiao-Chi Chuang
Induction of PM2.5-associated lung cancer in response to EGFR-tyrosine kinase inhibitors (EGFR-TKI) remains unclear. Polycyclic aromatic hydrocarbons (PAHs) and their polar derivatives (oxygenated PAHs: OPAHs and azaarenes: AZAs) were characterized in fine particulates (PM2.5) emitted from indoor coal combustion. Samples were collected in Xuanwei (Yunnan Province), a region in China with a high rate of lung cancer. Human lung adenocarcinoma cells A549 (with wild-type EGFR) and HCC827 (with EGFR mutation) were exposed to the PM2...
November 2016: Environmental Pollution
Angel Belles, Claire Alary, Justine Criquet, Gabriel Billon
In this paper, a method for evaluating the in-situ degradation of nitro polycyclic aromatic hydrocarbons (nitro-PAH) in sediments is presented. The methodology is adapted from the passive sampler technique, which commonly uses the dissipation rate of labeled compounds loaded in passive sampler devices to sense the environmental conditions of exposure. In the present study, polymeric passive samplers (made of polyethylene strips) loaded with a set of labeled polycyclic aromatic hydrocarbons (PAH) and nitro-PAH were immersed in sediments (in field and laboratory conditions) to track the degradation processes...
December 2016: Chemosphere
Cameron J Mackie, Alessandra Candian, Xinchuan Huang, Elena Maltseva, Annemieke Petrignani, Jos Oomens, Andrew L Mattioda, Wybren Jan Buma, Timothy J Lee, Alexander G G M Tielens
The study of interstellar polycyclic aromatic hydrocarbons (PAHs) relies heavily on theoretically predicted infrared spectra. Most earlier studies use scaled harmonic frequencies for band positions and the double harmonic approximation for intensities. However, recent high-resolution gas-phase experimental spectroscopic studies have shown that the harmonic approximation is not sufficient to reproduce experimental results. In our previous work, we presented the anharmonic theoretical spectra of three linear PAHs, showing the importance of including anharmonicities into the theoretical calculations...
August 28, 2016: Journal of Chemical Physics
Yoshiaki Shoji, Naoki Tanaka, Sho Muranaka, Naoki Shigeno, Haruka Sugiyama, Kumiko Takenouchi, Fatin Hajjaj, Takanori Fukushima
C-C bond coupling reactions illustrate the wealth of organic transformations, which are usually mediated by organotransition metal complexes. Here, we show that a borafluorene with a B-Cl moiety can mediate sequential alkyne insertion (1,2-carboboration) and deborylation/Csp(2)-Csp(2) coupling reactions, leading to aromatic molecules. The first step, which affords a borepin derivative, proceeds very efficiently between the borafluorene and various alkynes by simply mixing these two components. The second step is triggered by a one-electron oxidation of the borepin derivative, which results in the formation of a phenanthrene framework...
2016: Nature Communications
Carlos A Manzano, Derek Muir, Jane Kirk, Camilla Teixeira, May Siu, Xiaowa Wang, Jean-Pierre Charland, David Schindler, Erin Kelly
Atmospheric deposition of polycyclic aromatic compounds (PACs) via and onto snow, and their releasing during spring snowmelt has been a concern in the Athabasca Oil Sands Region of Alberta. This study was designed to evaluate the concentrations, loadings, and distribution of PACs in springtime snowpack and how they have changed since the first study in 2008. Snowpack samples were collected in late winters 2011-2014 at varying distances from the main developments. PAC concentration and deposition declined exponentially with distance, with pyrenes, chrysenes, and dibenzothiophenes dominating the distribution within the first 50 km...
September 2016: Environmental Monitoring and Assessment
Rafael Friedrich de Lima, Rafael Gomes Dionello, Maria do Carmo Ruaro Peralba, Simone Barrionuevo, Lauri Lourenço Radunz, Francisco Wilson Reichert Júnior
Grain drying using firewood as fuel for air heating, with direct fire, is still widely used in Brazil. The combustion of organic material, such as wood, can generate polycyclic aromatic hydrocarbons (PAHs) which are known to have carcinogenic potential. In the present work corn grain drying was carried out at three drying air temperatures: 60°C, 60/80°C and 80°C. Following the drying process, the presence and quantification of PAH in the corn grains was investigated. After extracting the PAHs of the matrix, the material was subjected to analysis by gas chromatography with mass detector...
January 15, 2017: Food Chemistry
Lingkui Meng, Takao Fujikawa, Motonobu Kuwayama, Yasutomo Segawa, Kenichiro Itami
A simple yet effective method for the formation of thiophene-fused π-systems is reported. When arylethynyl-substituted polycyclic arenes were heated in DMF in the presence of elemental sulfur, the corresponding thiophene-fused polycyclic arenes were obtained via cleavage of the ortho-C-H bond. Thus, arylethynylated naphthalenes, fluoranthenes, pyrenes, corannulenes, chrysenes, and benzo[c]naphtho[2,1-p]chrysenes were effectively converted into the corresponding thiophene-fused π-systems. Apart from polycyclic hydrocarbons, thiophene derivatives are also susceptible to this reaction...
August 17, 2016: Journal of the American Chemical Society
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