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Sample records for anthracene

  1. Thermal and Optoelectronic Properties of Anthracene and Dibenz[a,c]Anthracene

    Institute of Scientific and Technical Information of China (English)

    MUDDASIR Hanif; WANG Zhi-ming; YANG Bing; LU Ping; MA Yu-guang

    2013-01-01

    The basic characteristics of anthracene(AN) and dibenz[a,c]anthracene(D[a,c]A) derivatives,important semiconductors,were systematically studied.Differential scanning calorimetry(DSC) shows that D[a,c]A has the reversibility of solid and liquid phases.Thermalgravimetric analysis(TGA) shows that D[a,c]A exhibits higher Td(decomposition temperature),which indicates D[a,c]A,as active layers,should be more suitable to being made into stable devices.D[a,c]A shows blue-shifted UV-Vis absorption and emission despite increased conjugation compared to anthracene due to different symmetries.Both the compounds are planar and show weak blue fluorescence in the tetrahydrofuran(THF) solution and higher fluorescence in the solid-state,due to different energy levels in solution and solid-state,explained via Jablonski diagram.

  2. o-Carborane-based anthracene: a variety of emission behaviors.

    Science.gov (United States)

    Naito, Hirofumi; Morisaki, Yasuhiro; Chujo, Yoshiki

    2015-04-20

    An o-carborane-based anthracene was synthesized, and single crystals, with incorporated solvent molecules, were obtained from the CHCl3 , CH2 Cl2 , and C6 H6 solutions. The anthracene ring in the crystal is highly distorted by the formation of a π-stacked dimer between the anthracene units. The crystals exhibited a variety of emission behaviors such as aggregation-induced emission (AIE), crystallization-induced emission (CIE), aggregation-caused quenching (ACQ), and multichromism. PMID:25729004

  3. Anthracene dosimeter characterization under radiotherapy photons

    International Nuclear Information System (INIS)

    New radiotherapy techniques such as intensity-modulated radiation therapy and stereotactic radiosurgery have increased the need for dosimeters that can provide measurements in real time with high spatial resolution. Organic scintillation dosimeters are able to measure with accuracy small radiation fields and fields with high gradients, besides having advantages such as water and soft tissue equivalence and the possibility to be used in vivo. Anthracene is an organic scintillator crystal with the highest known scintillation efficiency among organic scintillation materials. The objective of this work is to characterize the anthracene as a dosimeter under radiotherapy photons energies, analysing its signal against average granulosity, intern capsule diameter, absorbed dose, absorbed dose rate, photon energy and its spatial resolution; with the last one analysed under three methods (edge spread function, line spread function and modulation transfer function). The photons energies used were 1.25 MeV (60Co), 0.661 MeV (137Cs) and X-rays (effective energies of 28.4; 46.5; 48.5; 94.0 e 106.0 keV). The scintillation detection system consisted of an optical fiber with one end attached to the anthracene capsule and the other to a photomultiplier tube maintained by power supply followed by an electrometer. Once Cerenkov radiation occurs in the optical fiber, it was removed from the total scintillation signal trough the subtraction of the signal, taken irradiating the optical fiber without the anthracene attached to one of its extremity. From results obtained, one can infer that the dosimeter signal increases proportionally with average granulosity and intern capsule diameter. The signal is linearly dependent of absorbed dose, linearly dependent of low photons energies and independent for high photons energies, as well as independent of the absorbed dose rate. From the spatial resolution values obtained it was possible to infer that the one obtained through modulation transfer

  4. Preparation and spectral characteristics of anthracene/tetracene mixed crystals

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A series of tetracene-doped anthracene crystals with different doping concentrations(the highest mo-lar ratio 100:1) are grown from solution.Crystal structures and optical characteristics of the above mixed crystals are investigated at room temperature.By changing the doping concentrations,the fluorescence can be adjusted from blue-green to green and even to yellow-green.The emission spectra of anthracene/tetracene(An/Te) mixed crystals reveal the sensitized fluorescence of tetracene and the partial quenching of anthracene emission.The data of transient photoluminescence(PL) decays illus-trate that in An/Te mixed crystals,the decay of anthracene becomes faster,while the PL lifetime of tet-racene is longer than that of the tetracene single crystals.All above experimental results suggest that there is excitation energy transfer from anthracene to tetracene in the mixed crystals.

  5. Assessing Anthracene and Arsenic Contamination within Buffalo River Sediments

    OpenAIRE

    Adrian Gawedzki; K. Wayne Forsythe

    2012-01-01

    Anthracene and arsenic contamination concentrations at various depths in the Buffalo River were analyzed in this study. Anthracene is known to cause damage to human skin and arsenic has been linked to lung and liver cancer. The Buffalo River is labelled as an Area of Concern defined by the Great Lakes Water Quality Agreement between Canada and the United States. It has a long history of industrial activity located in its near vicinity that has contributed to its pollution. An ordinary kriging...

  6. Anthracene + Pyrene Solid Mixtures: Eutectic and Azeotropic Character.

    Science.gov (United States)

    Rice, James W; Fu, Jinxia; Suuberg, Eric M

    2010-09-01

    To better characterize the thermodynamic behavior of a binary polycyclic aromatic hydrocarbon mixture, thermochemical and vapor pressure experiments were used to examine the phase behavior of the anthracene (1) + pyrene (2) system. A solid-liquid phase diagram was mapped for the mixture. A eutectic point occurs at 404 K at x(1) = 0.22. A model based on eutectic formation can be used to predict the enthalpy of fusion associated with the mixture. For mixtures that contain x(1) < 0.90, the enthalpy of fusion is near that of pure pyrene. This and X-ray diffraction results indicate that mixtures of anthracene and pyrene have pyrene-like crystal structures and energetics until the composition nears that of pure anthracene. Solid-vapor equilibrium studies show that mixtures of anthracene and pyrene form solid azeotropes at x(1) of 0.03 and 0.14. Additionally, mixtures at x(1) = 0.99 sublime at the vapor pressure of pure anthracene, suggesting that anthracene behavior is not significantly influenced by x(2) = 0.01 in the crystal structure.

  7. Fungal biodegradation of anthracene-polluted cork: A comparative study.

    Science.gov (United States)

    Jové, Patrícia; Olivella, Maria À; Camarero, Susana; Caixach, Josep; Planas, Carles; Cano, Laura; De Las Heras, Francesc X

    2016-01-01

    The efficiency of cork waste in adsorbing aqueous polycyclic aromatic hydrocarbons (PAHs) has been previously reported. Biodegradation of contaminated cork using filamentous fungi could be a good alternative for detoxifying cork to facilitate its final processing. For this purpose, the degradation efficiency of anthracene by three ligninolytic white-rot fungi (Phanerochaete chrysosporium, Irpex lacteus and Pleurotus ostreatus) and three non-ligninolytic fungi which are found in the cork itself (Aspergillus niger, Penicillium simplicissimum and Mucor racemosus) are compared. Anthracene degradation by all fungi was examined in solid-phase cultures after 0, 16, 30 and 61 days. The degradation products of anthracene by P. simplicissimum and I. lacteus were also identified by GC-MS and a metabolic pathway was proposed for P. simplicissimum. Results show that all the fungi tested degraded anthracene. After 61 days of incubation, approximately 86%, 40%, and 38% of the initial concentration of anthracene (i.e., 100 µM) was degraded by P. simplicissimum, P. chrysosporium and I. lacteus, respectively. The rest of the fungi degraded anthracene to a lesser extent (cork itself, could be used as an efficient degrader of PAH-contaminated cork.

  8. Transformation of anthracene on various cation-modified clay minerals.

    Science.gov (United States)

    Li, Li; Jia, Hanzhong; Li, Xiyou; Wang, Chuanyi

    2015-01-01

    In this study, anthracene was employed as a probe to explore the potential catalytic effect of clay minerals in soil environment. Clay minerals saturated with various exchangeable cations were tested. The rate of anthracene transformation follows the order: Fe-smectite > Cu-smectite > Al-smectite ≈ Ca-smectite ≈ Mg-smectite ≈ Na-smectite. This suggests that transition-metal ions such as Fe(III) play an important role in anthracene transformation. Among Fe(III)-saturated clays, Fe(III)-smectite exhibits the highest catalytic activity followed by Fe(III)-illite, Fe(III)-pyrophyllite, and Fe(III)-kaolinite, which is in agreement with the interlayer Fe(III) content. Moreover, effects by two common environmental factors, pH and relative humidity (RH), were evaluated. With an increase in pH or RH, the rate of anthracene transformation decreases rapidly at first and then is leveled off. GC-MS analysis identifies that the final product of anthracene transformation is 9,10-anthraquinone, a more bioavailable molecule compared to anthracene. The transformation process mainly involves cation-π bonding, electron transfer leading to cation radical, and further oxidation by chemisorbed O2. The present work provides valuable insights into the abiotic transformation and the fate of PAHs in the soil environment and the development of contaminated land remediation technologies.

  9. Electronic structures and optical properties of two anthracene derivatives

    Institute of Scientific and Technical Information of China (English)

    ZHANG Peng; XIA Baohui; SUN Yinghui; YANG Bing; TIAN Wenjing; WANG Yue; ZHANG Guo

    2006-01-01

    The electronic structures and the optical properties of two anthracene derivatives, DBMA and DAA, are investigated by both experimental techniques and quantum chemical calculations. The cyclic voltammetry and differential pulse polarograph measurement revealed that the introduction of benzol-imidazol and pyrrolo-pyridine group on the anthracene block can affect the electrochemical behavior of DBMA and DAA. Both UV/visible absorption and emission spectra of DBMA and DAA are red-shifted in contrast to the unsubstituted anthracene, so that the anthracene derivatives emit at blue-green region and the luminescence yields are remarkably elevated (over 90%). The B3LYP/6-31G theoretical calculations explored that the electronic structures of the anthracene derivatives are perturbed by the side substitutes on the anthracene block, and the slight variation of the electronic structures results in the enhanced electron accepting ability and the decrease of the HOMO-LUMO energy gap,which is the origin of the emission to be shifted to blue-green region. The non-planar geometry structures of DBMA and DAA are responsible for the excellent luminescence yields.

  10. Interaction Mechanism of Anthracene with Benzoic Acid and Its Derivatives

    Institute of Scientific and Technical Information of China (English)

    HE Ying-Ying; WANG Xiao-Chang; FAN Xiao-Yuan; ZHAO Bo; JIN Peng-Kang

    2008-01-01

    Interaction mechanism of anthracene, one of the typical polycyclic aromatic hydrocarbons, with benzoic acid and its hydroxyl-substituted derivatives, o-hydroxylbenzoic acid and p-hydroxylbenzoic acid, were studied using FFIR, UV and fluorescence spectra. The experiments confirmed that there was a specific and oriented interaction between anthracene and the aromatic carboxylic acids, and the bonding mode depended on both the chemical struc- ture of reactants and acidity of solution. The π-H hydrogen bond played a main role in the interaction between an-thracene and the aromatic carboxylic proton of benzoic acid or o-hydroxylbenzoic acid when pH≤pK, and the π-π electron donor-acceptor (EDA) interaction increasingly became the main binding mode when pH>pK. The de-crease of interaction intensity of benzoic acid was observed by introducing hydroxyl at its ortho position. The spe-cial D-π-A structure of p-hydroxylbenzoic acid made it easy to form the planar multi-molecule congeries that could interact with anthracene, so the interaction between anthracene and p-hydroxylbenzoic acid always followed the π-π EDA model no matter the solution acidity. For p-hydroxylbenzoic acid, the π-π interaction mode remained un-changed when pH increased from 2.0 to 10.0, and the binding intensity was higher than that between benzoic acid and anthracene because of the formation of the multi-molecule congeries.

  11. Blue Fluorescent Materials Composed of Anthracene-Aryl Amine-Anthracene Derivatives for Organic Light-Emitting Diodes.

    Science.gov (United States)

    Lee, Seul Bee; Song, Ji Young; Yang, Hyung Jin; Kim, Young Kwan; Yoon, Seung Soo

    2015-07-01

    Blue fluorescent emitters based on anthracene-aryl amine-anthracene derivatives were studied for efficient OLEDs. Compound 1 exhibited efficient EL propereties with luminous and power efficien- cies of 4.50 cd/A and 1.75 lm/W at 200 mA/cm2, respectively and CIE coordinates of (0.18, 0.26) at 7.0 V.

  12. Assessing Anthracene and Arsenic Contamination within Buffalo River Sediments

    Directory of Open Access Journals (Sweden)

    Adrian Gawedzki

    2012-01-01

    Full Text Available Anthracene and arsenic contamination concentrations at various depths in the Buffalo River were analyzed in this study. Anthracene is known to cause damage to human skin and arsenic has been linked to lung and liver cancer. The Buffalo River is labelled as an Area of Concern defined by the Great Lakes Water Quality Agreement between Canada and the United States. It has a long history of industrial activity located in its near vicinity that has contributed to its pollution. An ordinary kriging spatial interpolation technique was used to calculate estimates between sample locations for anthracene and arsenic at various depths. The results show that both anthracene and arsenic surface sediment (0–30 cm is less contaminated than all subsurface depths. There is variability of pollution within the different subsurface levels (30–60 cm, 60–90 cm, 90–120 cm, 120–150 cm and along the river course, but major clusters are identified throughout all depths for both anthracene and arsenic.

  13. Degradation of anthracene, pyrene and benzo[a]anthracene in aqueous solution by chlorine dioxide

    Institute of Scientific and Technical Information of China (English)

    LIU; Jinquan; HUANG; Junli; SU; Liqiang; CAO; Xiangyu; JI; Ying

    2006-01-01

    Polycyclic aromatic hydrocarbons (PAHs) constitute an important group of micropollutants, which are known to be mutagenic, carcinogenic and/or co-carcinogenic and relatively persistent in the environment. The effects of chlorine dioxide (ClO2) on the degradation of anthracene (ANTH), pyrene (PYR) and benzo[a]anthracene (BaA) in aqueous solution were investigated using high performance liquid chromatography (HPLC). In preliminary experiments, it was observed that ClO2 could remove these three PAHs effectively within a short time. Several factors including reaction time, the concentration of ClO2 and pH of the reaction mixture influencing the degradation ratio of PAHs have been studied by batch experiments. The results showed that the degradation ratio of PAHs was affected by reaction time and the concentration of ClO2 instead of pH. The degradation ratio of ANTH, PYR and BaA could reach their maximum as approximately 99.0%, 67.5% and 89.5%, respectively, under the condition as follows: reaction time 30, 60 and 120 min, the concentration of ClO2 0.1, 0.4 and 0.5 mmol·L-1, and pH 7.2. ANTH was selected as the representative to study the reaction mechanism with ClO2. The oxidation products formed in the reaction of ANTH with ClO2 were tentatively identified by gas chromatography-mass spectrometry (GC-MS), and the results showed that the main product was 9, 10-anthraquinone, which could be biodegraded more easily and quickly than ANTH. Through analyzing the reaction properties of ANTH and ClO2, the possible pathway for the ANTH-ClO2 reaction was proposed based on the theory of single electron transfer (SET).

  14. Toxic photoproducts of phenanthrene and anthracene in sunlight

    Energy Technology Data Exchange (ETDEWEB)

    Duxbury, C.L.; McConkey, B.J.; Mallakin, A.; Dixon, D.G.; Greenberg, B.M. [Univ. of Waterloo, Ontario (Canada). Dept. of Biology

    1995-12-31

    Phenanthrene and anthracene, two of the most prevalent PAHs, undergo significant increases in toxicity on exposure to sunlight. Over a period of several days exposure to light, the toxicity of an aqueous solution of phenanthrene or anthracene increased dramatically. This increase in toxicity is largely due to the primary products formed by these two PAHs due to light exposure. These compounds are more toxic than the parent compounds at equimolar concentrations. Although anthracene is a potent photosensitizer, phenanthrene did not exhibit a significant increase in toxicity due to photosensitization. Photo-oxidation was the principal cause of photoinduced toxicity, with 9,10-phenanthrenequinone being the primary product. This compound is more water soluble than phenanthrene increasing its bioavailability. In addition, mixtures of phenanthrene and 9,10-phenanthrenequinone exhibited toxicity similar to the quinone added alone. This was shown by joint toxicity testing using Lemna gibba and Daphnia magna. These two organisms are currently being used in the lab to further test individual oxidized products of anthracene and phenanthrene that occur as a result of exposure to sunlight.

  15. Infrared spectroscopy of fullerene C60/anthracene adducts

    CERN Document Server

    Garcia-Hernandez, D A; Manchado, A

    2013-01-01

    Recent Spitzer Space Telescope observations of several astrophysical environments such as Planetary Nebulae, Reflection Nebulae, and R Coronae Borealis stars show the simultaneous presence of mid-infrared features attributed to neutral fullerene molecules (i.e., C60) and polycyclic aromatic hydrocarbons (PAHs). If C60 fullerenes and PAHs coexist in fullerene-rich space environments, then C60 may easily form adducts with a number of different PAH molecules; at least with catacondensed PAHs. Here we present the laboratory infrared spectra (~2-25 um) of C60 fullerene and anthracene Dies-Alder mono- and bis-adducts as produced by sonochemical synthesis. We find that C60/anthracene Diels-Alder adducts display spectral features strikingly similar to those from C60 (and C70) fullerenes and other unidentified infrared emission features. Thus, fullerene-adducts - if formed under astrophysical conditions and stable/abundant enough - may contribute to the infrared emission features observed in fullerene-containing circu...

  16. Photocatalytic Degradation of Anthracene in Closed System Reactor

    Directory of Open Access Journals (Sweden)

    Faiq F. Karam

    2014-01-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs represent a large class of persistent organic pollutants in an environment of special concern because they have carcinogenic and mutagenic activity. In this paper, we focus on and discuss the effect of different parameters, for instance, initial concentration of Anthracene, temperature, and light intensity, on the degradation rate. These parameters were adjusted at pH 6.8 in the presence of the semiconductor materials (TiO2 as photocatalysts over UV light. The main product of Anthracene photodegradation is 9,10-Anthraquinone which isidentified and compared with the standard compound by GC-MS. Our results indicate that the optimum conditions for the best rate of degradation are 25 ppm concentration of Anthracene, regulating the reaction vessel at 308.15 K and 2.5 mW/cm2 of light intensity at 175 mg/100 mL of titanium dioxide (P25.

  17. Density Functional Studies of Molecular Polarizabilities. 7. Anthracene and Phenanthrene

    Directory of Open Access Journals (Sweden)

    Humberto J. Soscun Machado

    2000-03-01

    Full Text Available We report accurate Ab Initio studies of the static dipole polarizabilities of anthracene and phenanthrene. Geometries were optimized at the HF/6-311G(3d,2p level of theory. Dipole polarizabilities were calculated at the HF/6-311++G(3d,2p and BLYP/6-311++G(3d,2p levels of theory, using HF/6-311G(3d,2p geometries. The calculated dipole polarizabilities for anthracene are compared with experiment. Inclusion of electron correlation using the BLYP procedure increases the L and M components of the dipole polarizability, but not the perpendicular (N component. Examination of corresponding BLYP results for the polyacene series benzene, naphthalene and anthracene shows that the normal component of the dipole polarizability scales linearly with the number of benzene ring units, with an increment of 20.8 au. The medium component also scales linearly with an increment of 42.8 atomic units. The long component does not scale linearly. Semi-emiprical AM1 calculations are also given for comparison; the normal component of the dipole polarizability tensor is poorly represented by such calculations.

  18. The effects of anthracene and methylated anthracenes on gap junctional intercellular communication in rat liver epithelial cells.

    Science.gov (United States)

    Upham, B L; Weis, L M; Rummel, A M; Masten, S J; Trosko, J E

    1996-12-01

    Polycyclic aromatic hydrocarbons (PAHs), many of which are known carcinogens, are derived from the pyrolysis of organic materials. A rich source of PAHs is cigarette smoke, which contains methylated anthracenes and phenanthrenes as the predominant PAHs. The tumor-promoting activity of cigarette smoke has been well documented. The down-regulation of gap junction intercellular communication (GJIC) by nongenotoxic chemicals and several oncogenes has been implicated in tumor promotion. Therefore, we determined the effects of the three isomers of methylanthracene on GJIC in WB-F344 rat liver epithelial cells. Anthracene and 2-methylanthracene did not significantly inhibit GJIC, whereas anthracene methylated in the 1 or 9 position reversibly inhibited GJIC with I50 values of 22 and 36 microM, respectively. Inhibition occurred within 15 min. In conclusion, the biological effect of methylanthracene depends on the ring position of the methyl group, and these inhibitory isomers could play a potential role in tumor promotion of methylated PAH-rich mixtures such as cigarette smoke and crude oil products. PMID:8954755

  19. The Use of Demulsifiers for Separating Water from Anthracene Oil

    Directory of Open Access Journals (Sweden)

    Zečević, N.

    2008-03-01

    Full Text Available The main feedstocks for the production of oil-furnace carbon black are different kinds of liquid hydrocarbons. The quality and utilization of oil-furnace carbon black mainly depends on the type of liquid hydrocarbons contained in the oil feedstocks.In practice, both carbochemical and petrochemical oils are used as feedstock sources. Carbochemical oils are fractions obtained during coal tar distillation. Anthracene oil is one of these oils. Depending on the conditions of distillation, coal tars contain up to w = 18·10 –2 highly aromatic fractions, which can be used as carbon black feedstock. The sulphur fraction of these oils can vary between w = 0.5 and 0.7·10 –2, depending on the origin of the coal. The availability of carbochemical oils obtained from coal tar is largely dependent on the production of coke used in the manufacture of steel. The quantities available today are insufficient to satisfy the demand for carbon black feedstock. In addition, in highly industrialized countries, production of carbochemicaloils is declining.Although, carbochemical oils are preferred in terms of efficiency, petrochemical oils are more important in terms of quantities available, particularly in the production of furnace blacks. These are residual oils resulting either from catalytic cracking processes or from the production of olefins in steam crackers using naphtha or gas oil as raw material. Nevertheless, the choice of carbon black feedstock is not determined merely by price and efficiency, but also by specific quality criteria. However, due to their origin, the feedstocks are mixtures of a large number of individual substances and are, therefore, not easy to characterize. More than 200 different components have been recorded in the range detectable by gas chromatography.Some important components of carbon black feedstock are listed in table 1.1 An important parameter for the evaluation of carbon black feedstock is density, since it increases with

  20. Measurement of the Mean Inner Potentials of Anthracene and Naphthalene

    Science.gov (United States)

    Lunt, Richard R.; Kéna-Cohen, Stéphane; Benziger, Jay B.; Forrest, Stephen R.

    2009-02-01

    The mean inner potential in metals, insulators, and semiconductors provides fundamental information regarding the electronic structure of the material. Here, we measure the mean inner potentials of the two archetype linear polyacenes: anthracence and naphthalene. We determine the mean inner potentials of single crystalline anthracene of 5.9 V (±0.3V), and naphthalene of 5.4 V (±0.3V) based on analysis of Kikuchi patterns observed using high-pressure reflection high energy electron diffraction. We show that the inner potential of a range of organic molecular semiconductors can be estimated from their diamagnetic susceptibilities.

  1. Anthracene + Pyrene Solid Mixtures: Eutectic and Azeotropic Character

    OpenAIRE

    Rice, James W.; Fu, Jinxia; Suuberg, Eric M.

    2010-01-01

    To better characterize the thermodynamic behavior of a binary polycyclic aromatic hydrocarbon mixture, thermochemical and vapor pressure experiments were used to examine the phase behavior of the anthracene (1) + pyrene (2) system. A solid-liquid phase diagram was mapped for the mixture. A eutectic point occurs at 404 K at x1 = 0.22. A model based on eutectic formation can be used to predict the enthalpy of fusion associated with the mixture. For mixtures that contain x1 < 0.90, the enthalpy ...

  2. Macrocrystals of Colloidal Quantum Dots in Anthracene: Exciton Transfer and Polarized Emission

    Science.gov (United States)

    Soran-Erdem, Zeliha; Erdem, Talha; Hernandez-Martinez, Pedro Ludwig; Akgul, Mehmet Zafer; Gaponik, Nikolai; Demir, Hilmi Volkan

    We systematically investigate the exciton energy transfer from anthracene host (donor) to quantum dots (acceptor) in a centimeter-scale macrocrystal of nonpolar colloidal quantum dots incorporated into anthracene. The decrease in photoluminescence lifetime of the donor anthracene indicate a strong energy transfer with increasing quantum dot concentration in the macrocrystals. In addition, anisotropic emission from the isotropic quantum dots in anthracene macrocrystals was observed. The quantum dots inside the anthracene host acquired a polarization ratio of ~1.5 at 0 degree collection angle, and this increases to ~2.5 at the collection angle of 60 degree. Finally, a proof-of-concept application of these excitonic macrocrystals as tunable color converters was employed in light-emitting diodes. Bilkent University.

  3. Enhanced tolerance and remediation of anthracene by transgenic tobacco plants expressing a fungal glutathione transferase gene

    Energy Technology Data Exchange (ETDEWEB)

    Dixit, Prachy; Mukherjee, Prasun K.; Sherkhane, Pramod D.; Kale, Sharad P. [Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Eapen, Susan, E-mail: eapenhome@yahoo.com [Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2011-08-15

    Highlights: {yields} Transgenic plants expressing a TvGST gene were tested for tolerance, uptake and degradation of anthracene. {yields} Transgenic plants were more tolerant to anthracene and take up more anthracene from soil and solutions compared to control plants. {yields} Using in vitro T{sub 1} seedlings, we showed that anthracene-a three fused benzene ring compound was phytodegraded to naphthalene derivatives, having two benzene rings. {yields} This is the first time that a transgenic plant was shown to have the potential to phytodegrade anthracene. - Abstract: Plants can be used for remediation of polyaromatic hydrocarbons, which are known to be a major concern for human health. Metabolism of xenobiotic compounds in plants occurs in three phases and glutathione transferases (GST) mediate phase II of xenobiotic transformation. Plants, although have GSTs, they are not very efficient for degradation of exogenous recalcitrant xenobiotics including polyaromatic hydrocarbons. Hence, heterologous expression of efficient GSTs in plants may improve their remediation and degradation potential of xenobiotics. In the present study, we investigated the potential of transgenic tobacco plants expressing a Trichoderma virens GST for tolerance, remediation and degradation of anthracene-a recalcitrant polyaromatic hydrocarbon. Transgenic plants with fungal GST showed enhanced tolerance to anthracene compared to control plants. Remediation of {sup 14}C uniformly labeled anthracene from solutions and soil by transgenic tobacco plants was higher compared to wild-type plants. Transgenic plants (T{sub 0} and T{sub 1}) degraded anthracene to naphthalene derivatives, while no such degradation was observed in wild-type plants. The present work has shown that in planta expression of a fungal GST in tobacco imparted enhanced tolerance as well as higher remediation potential of anthracene compared to wild-type plants.

  4. Direct Modulation of Microtubule Stability Contributes to Anthracene General Anesthesia

    Science.gov (United States)

    Emerson, Daniel J.; Weiser, Brian P.; Psonis, John; Liao, Zhengzheng; Taratula, Olena; Fiamengo, Ashley; Wang, Xiaozhao; Sugasawa, Keizo; Smith, Amos B.; Eckenhoff, Roderic G; Dmochowski, Ivan J.

    2013-01-01

    Recently, we identified 1-aminoanthracene as a fluorescent general anesthetic. To investigate the mechanism of action, a photoactive analogue, 1-azidoanthracene, was synthesized. Administration of 1-azidoanthracene to albino stage 40–47 tadpoles was found to immobilize animals upon near-UV irradiation of the forebrain region. The immobilization was often reversible, but it was characterized by a longer duration consistent with covalent attachment of the ligand to functionally important targets. IEF/SDS-PAGE examination of irradiated tadpole brain homogenate revealed labeled protein, identified by mass spectrometry as β-tubulin. In vitro assays with aminoanthracene-cross-linked tubulin indicated inhibition of microtubule polymerization, similar to colchicine. Tandem mass spectrometry confirmed anthracene binding near the colchicine site. Stage 40–47 tadpoles were also incubated 1 h with microtubule stabilizing agents, epothilone D or discodermolide, followed by dosing with 1-aminoanthracene. The effective concentration of 1-aminoanthracene required to immobilize the tadpoles was significantly increased in the presence of either microtubule stabilizing agent. Epothilone D similarly mitigated the effects of a clinical neurosteroid general anesthetic, allopregnanolone, believed to occupy the colchicine site in tubulin. We conclude that neuronal microtubules are “on-pathway” targets for anthracene general anesthetics and may also represent functional targets for some neurosteroid general anesthetics. PMID:23484901

  5. Copolyacrylates with phenylalanine and anthracene entities prepared by ATRP and microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Buruiana, E.C., E-mail: emilbur@icmpp.r [Romanian Academy, Petru Poni Institute of Macromolecular Chemistry, Grigore Ghica Voda Alley 41A, 700487 Iasi (Romania); Murariu, Mioara; Buruiana, Tinca [Romanian Academy, Petru Poni Institute of Macromolecular Chemistry, Grigore Ghica Voda Alley 41A, 700487 Iasi (Romania)

    2010-10-15

    In this study, two amino acid copolymers containing anthracene incorporated either on the one end, poly(N-acryloyl-L-phenylalanine-co-methyl methacrylate)-1 or as pendant groups, poly-(N-acryloyl-L-phenylalanine-co-methyl methacrylate)-2 were prepared directly from N-acryloyl-L-phenylalanine (APhe) and methyl methacrylate (MMA) through atom transfer radical polymerization (ATRP) and microwave-assisted synthesis. In the first case, 9-(chloromethyl)anthracene was used as an ATRP-initiator to obtain a copolymer that contains amino acid sequences and anthracene end-capped units (0.03 molar fraction). Rapid synthesis of copolymer under microwave irradiation (250 W) in the presence of 1,1'-azobis(cyclohexanecarbonitrile) used as an initiator was followed of a functionalization of the formed copolymer with an anthracene derivative yielding copolyacrylate with pendant anthracene (0.02 molar fraction). The structure of the copolymers was verified by {sup 1}H NMR, UV-Vis and FTIR spectroscopy, gel permeation chromatography (GPC), and fluorescence spectroscopy. The fluorescence quenching process of anthracene which exists in copolymers by FeCl{sub 3}, cobalt acetate, nitrobenzene, maleic anhydride, diethylaniline and nitromethane in DMF solutions shows that this involves an electron transfer between the excited state anthracene and the present transitional metal cations, more efficiently being FeCl{sub 3} for poly-(APhe-co-MMA)-1 and cobalt acetate for the latter copolymer.

  6. The onset of anthracene phototoxicity to Lemna gibba and the protective effects of humic acid

    Energy Technology Data Exchange (ETDEWEB)

    Gensemer, R.W. [Univ. of Guelph, Ontario (Canada); Dixon, D.G.; Greenberg, B.M. [Univ. of Waterloo, Ontario (Canada)

    1994-12-31

    The toxicity of anthracene to the freshwater duckweed Lemna gibba is strongly photo-induced in the presence of light containing natural levels of ultraviolet (UV) radiation. This was demonstrated using 8-day static renewal bioassays at an anthracene concentration of 2 mg-L{sup {minus}1}. Plants were incubated under simulated solar radiation (SSR) which mimics UV levels found in natural sunlight at a visible:UV-A:UV-B ratio of 100:10:1. Anthracene phototoxicity was expressed as inhibition of population growth and fluorescence induction decreases in chlorophyll content, and changes in low-temperature chlorophyll fluorescence emission scans. Furthermore, adding 6.2 mg-L-1 of an artificial humic acid ameliorated anthracene phototoxicity even though HA is also photo modified by UV light. However, anthracene inhibited photosynthesis days before the endpoint assays were performed. Therefore, the authors repeated these experiments at short time intervals following exposure to both light and chemical. Anthracene phototoxicity occurred after only 1 hour as detected by chlorophyll fluorescence induction, whereas chlorophyll contents and low-temperature fluorescence emission scans were not affected until 24--48 hours, respectively. Humic acid again ameliorated anthracene toxicity by delaying the negative physiological events by approximately 24 hours.

  7. Excited state kinetics of anthracene-bridge-aniline intramolecular exciplexes

    DEFF Research Database (Denmark)

    Thyrhaug, Erling; Hammershøj, Peter; Kjær, Kasper Skov;

    2014-01-01

    excited anthracene state (LE) and an excited state complex (exciplex, EP) in non-polar solvents. The kinetics of the excited state processes were established in decalin from the time-resolved emission, and was shown to be strongly influenced by an electron-transfer state (ET). For quantitative studies...... of the excited state dynamics, the presence of this state required the development of a numerical three-excited-state kinetic model to replace the commonly used two-excited-state model. The experimental results shows that the reaction rates are strongly influenced both by substituents and solvent, illustrating...... the importance of including all relevant states in the kinetic modeling. Ultimately it is established that the excited state dynamics can conveniently be followed by optical methods, and the applicability of the system as a model system in time-resolved X-ray scattering experiments is discussed....

  8. Photoluminescence and conductivity studies of anthracene-functionalized ruthenium nanoparticles

    Science.gov (United States)

    Chen, Wei; Pradhan, Sulolit; Chen, Shaowei

    2011-05-01

    Carbene-stabilized ruthenium nanoparticles were functionalized with anthryl moieties by olefin metathesis reactions with 9-vinylanthracene, at a surface concentration of about 19.7%, as estimated by 1H NMR spectroscopic measurements. Because of the conjugated metal-ligand interfacial bonding interactions, UV-vis measurements of the resulting nanoparticles showed a new broad absorption band centered at 612 nm, in addition to the peaks observed with monomeric vinylanthracene. FTIR measurements depicted apparent red-shifts of the aromatic vibrational stretches as compared to those of the monomeric vinylanthracene, suggestive of decreasing bonding order of the aromatic moieties as a result of extended conjugation between the particle-bound anthracene groups. Photoluminescence measurements confirmed the notion that effective intraparticle charge delocalization occurred by virtue of the conjugated metal-ligand interfacial bonding interactions, with apparent red-shifts of the excitation peaks and blue-shifts of the emission features, as compared to those of the monomeric vinylanthracene. The diminishment of the Stokes shift was, at least in part, attributed to the different chemical environments surrounding the anthryl moieties on the nanoparticle surface. Electronic conductivity measurements showed that because of the conjugated Ru z.dbd C π bonds, the activation energy for interparticle charge transport was about one order of magnitude lower than that observed with particles passivated by alkanethiolates. Additionally, whereas the original carbene-stabilized nanoparticles exhibited a semiconductor-metal transition within the temperature range of 100 to 320 K, anthracene-functionalized nanoparticles displayed apparent semiconducting behaviors with the ensemble conductivity increasing monotonically with temperature, most likely due to the disordering within the nanoparticle solids that arose from the different structures of the carbene ligands and anthryl moieties. These

  9. Biodegradation of naphthalene and anthracene by chemo-tactically active rhizobacteria of populus deltoides

    Directory of Open Access Journals (Sweden)

    Sandeep Bisht

    2010-12-01

    Full Text Available Several naphthalene and anthracene degrading bacteria were isolated from rhizosphere of Populus deltoides, which were growing in non-contaminated soil. Among these, four isolates, i.e. Kurthia sp., Micrococcus varians, Deinococcus radiodurans and Bacillus circulans utilized chrysene, benzene, toluene and xylene, in addition to anthracene and naphthalene. Kurthia sp and B. circulans showed positive chemotactic response for naphthalene and anthracene. The mean growth rate constant (K of isolates were found to increase with successive increase in substrate concentration (0.5 to 1.0 mg/50ml. B. circulans SBA12 and Kurthia SBA4 degraded 87.5% and 86.6% of anthracene while, Kurthia sp. SBA4, B. circulans SBA12, and M. varians SBA8 degraded 85.3 %, 95.8 % and 86.8 % of naphthalene respectively after 6 days of incubation as determined by HPLC analysis.

  10. Anthracene-fused BODIPYs as near-infrared dyes with high photostability

    KAUST Repository

    Zeng, Lintao

    2011-11-18

    An anthracene unit was successfully fused to the zigzag edge of a boron dipyrromethene (BODIPY) core by an FeCl 3-mediated oxidative cyclodehydrogenation reaction. Meanwhile, a dimer was also formed by both intramolecular cyclization and intermolecular coupling. The anthracene-fused BODIPY monomer 7a and dimer 7b showed small energy gaps (∼1.4 eV) and near-infrared absorption/emission. Moreover, they exhibited high photostability. © 2011 American Chemical Society.

  11. Consequences of Environmentally Hazardous Polycyclic Aromatic Hydrocarbon- Anthracene Treatment on Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Jignasha G Patel

    2015-09-01

    Full Text Available The study was aimed to determine the chronic toxicity of Polynuclear aromatic hydrocarbon – Anthracene in response to pigments and metabolic study on three different cyanobacterial species such as Synechocystis sp., Anabaena fertilissima, and Nostoc muscorum. Test organisms were treated at different doses and encountered LC50/Mean Lethal Concentration (at which 50% lethality/ growth reduction occur separately at 7.0 ppm for Synechocystis sp, 5.0 ppm for Anabaena fertilissima and 1.5 ppm for Nostoc muscorum. The influence of anthracene on pigments, metabolites and enzymes was carried out. The test doses caused concentration dependent and decreased pigments like carotenoids and phycobilliproteins. Depletion of carbohydrate by 65 to 80% and proteins by 58 to 78% was encountered with rise in Anthracene concentrations after 16th day exposure in case of Synechocystis sp however, phenols were found to raise by 26 to 37% with increased anthracene concentrations. Similar trend also observed in other two tested blue green algae. Thus the Synechocystis sp.is more tolerant to anthracene treatments as compare to Anabaena fertillissima but Nostoc muscorum showed highest sensitivity to anthracene.

  12. Syntheses and Chemosensory of Anthracene and Phenanthrene Bisimide Derivatives

    Science.gov (United States)

    Bogusz, Zachary A.

    2004-01-01

    As the present technology of biochemical weapons advances, it is essential for science to attempt to prepare our nation for such an occurrence. Various areas of current research are devoted to precautionary measures and potential antidotes for national security. A practical application of these precautions would be the development of a chemical capable of detecting harmful gas. The benefits of being capable to synthesis a chemical compound that would warn and identify potentially deadly gases would ensure a higher level of safety. The chemicals in question can be generalized as bisimide anthracene derivatives. The idea behind these compounds is that in the presence of certain nerve gases, the compound will actually fluoresce, giving an indication that there is a strong likelihood of the presence of a nerve gas and ensure the proper precautionary measures are taken. The fluorescence is due to the quenching of an electric proton transfer within the structure of the molecule. The system proves to be very unique on account of the fact that the fluorescence can be "turned off" by reducing the system. By utilizing the synthesis designed by Dr. Faysal Ilhan, four distinct compounds can be synthesized through photochemical reactions involving para- and ortho- diketones. The photochemistry involved is very modem and much research is being devoted to fully understanding the possibilities and alternative applications of such materials. and meta-nitro anthracene bisimide (ABI-NO2), the amine of each (ABI-NH2), a para- and meta-nitro phenanthrene bisimjde (PBI-NO2), and the amine of each (PBI-NH2). Upon synthesizing these distinct compounds, I must then purify and analyze them in order to obtain any relevant trends, behaviors, and characteristics. The chemical composition analyses that will be conducted are the procedures taken by Dr. Daniel Tyson on previous experiments. The results generated from the data will point further research in the correct direction and hopefully

  13. Long-term reproductive and behavioral toxicity of anthracene to fish in the presence of solar ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hall, A.T. [Sandoz Agro, Inc., Des Plaines, IL (United States); Oris, J.T. [Miami Univ. Oxford, OH (United States)

    1994-12-31

    The long-term, low-level effects of anthracene in the presence of solar ultraviolet radiation (SUVR) were examined in the fathead minnow (Pimephales promelas). Adult fish exposed to anthracene exhibited reduced egg laying capacity, with altered oocyte maturation as a potential mechanism of action. Eggs and larvae maternally exposed to anthracene exhibited reduced hatching success and severe developmental abnormalities when incubated under SUVR. The combination of reduced egg output and developmental effects resulted in an inhibition in reproductive capacity in the range of 70--100%. Maternal transfer of anthracene to eggs was efficient; the BCF was 717 for maternally exposed eggs. However, anthracene deputation from eggs after oviposition with only maternal PAH exposure was rapid; anthracene half-life from eggs equaled 1.3 days. Exposure to anthracene under SUVR altered locomotor activity patterns in fathead minnows by inducing hyperactivity or hypoactivity during the light or dark phases of the photoperiod, respectively. Altered activity patterns indicated potential effects of anthracene on the nervous system and/or pineal gland. These alterations disrupted normal activity patterns and reproductive behaviors, and thus have major implications on a fish`s ability to survive and reproduce. Anthracene, a model phototoxic PAH, has many potential sites of toxic action, and any organism exposed to such contaminants will be an considerable SUVR-enhanced risk in the environment.

  14. Optical absorption of the anthracene and temperature-dependent capacitance-voltage characteristics of the Au/anthracene/n-Si heterojunction in metal-organic-semiconductor configuration

    Science.gov (United States)

    Kaçus, H.; Aydoğan, Ş.; Ekinci, D.; Kurudirek, S. V.; Türüt, A.

    2015-11-01

    An anthracene film has been deposited on an n-type silicon to fabricate an Au/anthracene/n-Si junction device. The band gap of the anthracene film has been determined from the optical measurement as Eg=1.65 eV. After the fabrication of the Au/anthracene/n-Si junction device, temperature dependent capacitance-voltage characteristics in the range of 160-300 K were studied to obtain the junction parameters of the device. The diffusion potential, barrier height, Fermi energy level and donor concentration parameters have been determined from the linear 1/C2-V curves with reverse bias at all temperatures. Both Fermi energy level and the barrier height increased with the increasing temperature. Temperature-dependence of the barrier height has been attributed to inhomogeneous barrier, traps and interface states. The ionized donor concentrations have varied with the temperature in an unsystematic manner due to the trapping/de-trapping of the charges at various temperatures.

  15. Preparation of low toxicity pitches by thermal oxidative condensation of anthracene oil.

    Science.gov (United States)

    Alvarez, Patricia; Granda, Marcos; Sutil, Juan; Santamaría, Ricardo; Blanco, Clara; Menéndez, Rosa; José Fernández, Juan; Viña, José Antonio

    2009-11-01

    This article describes a novel industrial procedure for producing new pitches of low toxicity from anthracene oil, a byproduct of coal tar distillation. The procedure involves oxidative treatment in order to polymerize and condense the anthracene oil components followed by thermal treatment and distillation in order to obtain a pitch with the desired parameters. This sequence (oxidative treatment/thermal treatment/distillation) was repeated four times under reaction conditions of increasing severity in four cycles of anthracene oil processing to obtain the four pitches. The pitches had similar characteristics to those of standard binder coal tar pitches (e.g., softening point and wetting capacity). Because of the inherent composition of the parent anthracene oil, the pitches were found to be totally free of solid particles, i.e., primary quinoline insolubles and metals. The gas chromatography and gas chromatography/mass spectroscopy results revealed a consecutive decrease in toxicity with successive cycles of anthracene oil processing. Thus, the benzo[a]pyrene content decreased from 11.2 mg/g for the pitch in cycle one to 1.5 mg/g for the pitch with four processing cycles. The carcinogenicity of the pitches, evaluated on the basis of benzo[a]pyrene toxic equivalency factors, also followed the same tendency. The final carcinogenity values are nearly all lower than those of standard binder coal tar pitches.

  16. Influences of humic acid and fulvic acid on horizontal leaching behavior of anthracene in soil barriers.

    Science.gov (United States)

    Yu, Sheng; Li, Bang-Yu; Chen, Yi-Hu

    2015-12-01

    The influences of humic acid (HA) and fulvic acid (FA) on horizontal leaching behaviors of anthracene in barriers were investigated. Soil colloids (≤1 μm) were of concern because of their abilities of colloid-facilitated transport for hydrophobic organic compounds with soluble and insoluble organic matters. Through freely out of the barriers in the presence of soil colloids with FA added, the higher concentrations of anthracene were from 320 μg L(-1) (D1 and D3) to 390 μg L(-1) (D2 and D4) with 1 to 20 cm in length. The contents of anthracene were distributed evenly at 25 ng g(-1) dry weight (DW) (D1 and D3) and 11 ng g(-1) DW (D2 and D4) in barriers. Therefore, anthracene leaching behaviors were mainly induced by soil colloids with soluble organic matters. The insoluble organic matters would facilitate anthracene onto soil colloids and enhance the movement in and through porous media of soil matrix. PMID:26300357

  17. (E)-Methyl 3-(10-bromo­anthracen-9-yl)acrylate

    Science.gov (United States)

    Bugenhagen, Bernhard; Al Jasem, Yosef; Hindawi, Bassam al; Al Rawashdeh, Nathir; Thiemann, Thies

    2013-01-01

    In the title mol­ecule, C18H13BrO2, the anthracene unit forms an angle of 46.91 (2)° with the mean plane of the methyl acrylate moiety. In the crystal, the mol­ecules arrange themselves into strands parallel to [010] and, due to the crystal symmetry, there are eight strands crossing the unit cell. In each strand, mol­ecules form short C—H⋯O and C—H⋯π contacts and have their anthracene groups parallel to each other. Neighboring strands, related by a c-glide operation, are connected via C—H⋯O inter­actions and form a layer parallel to (100). The arrangement of the acrylate and anthracene groups in the crystal do not allow for [2 + 2] or [4 + 4] cyclo­addition. PMID:24046689

  18. Changes in bacterial community of anthracene bioremediation in municipal solid waste composting soil

    Institute of Scientific and Technical Information of China (English)

    Shu-ying ZHANG; Qing-feng WANG; Rui WAN; Shu-guang XIE

    2011-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are common contaminants in a municipal solid waste (MSW) composting site.Knowledge of changes in microbial structure is useful to identify particular PAH degraders.However,the microbial community in the MSW composting soil and its change associated with prolonged exposure to PAHs and subsequent biodegradation remain largely unknown.In this study,anthracene was selected as a model compound.The bacterial community structure was investigated using terminal restriction fragment length polymorphism (TRFLP) and 16S rRNA gene clone library analysis.The two bimolecular tools revealed a large shift of bacterial community structure after anthracene amendment and subsequent biodegradation.Genera Methylophilus,Mesorhizobium,and Terrimonas had potential links to anthracene biodegradation,suggesting a consortium playing an active role.

  19. Novel Organic Sensitizers Containing 2,6-Difunctionalized Anthracene Unit for Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Jiann T. Lin

    2012-08-01

    Full Text Available A series of new organic dyes comprising different amines as electron donors, 2-(6-substituted-anthracen-2-yl-thiophene as the π-conjugated bridge, and cyanoacrylic acid group as an electron acceptor and anchoring group, have been synthesized. There exists charge transfer transition from arylamine and anthracene to the acceptor in these compounds, as evidenced from the photophysical measurements and the computational results. Under one sun (AM 1.5 illumination, dye-sensitized solar cells (DSSCs using these dyes as the sensitizers exhibited efficiencies ranging from 1.62% to 2.88%, surpassing that using 9,10-difunctionalized anthracene-based sensitizer.

  20. SYNTHESIS OF 1,2-ACEANTHRYLENEDIONE THROUGH ACYLATION OF ANTHRACENE WITH OXALYL CHLORIDE

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chunyan; CHEN Min; YU Long; JIANG Deli YAN Yongsheng

    2007-01-01

    Acylation of anthracene and oxalyl chloride in the presence of anhydrous AlCl3 was investigated. Pure 1,2-aceanthrylenedione, which is used as new functional macromolecule, was prepared by extraction and recrystallation. The structure of 1,2-aceanthrylenedione was identified by measure of melting point, GC/MS, FTIR and 1HNMR analyses. The influences of various parameters,such as solvent, dosage of catalyst, molar ratio of anthracene to oxalyl chloride, reaction temperature, and reaction time were studied. The anhydrous AlCl3 was found to catalyze the reaction with high yeild and good selectivity. When the reaction temperature is 303K, reaction time is 5h and molar ratio of anthracene to oxalyl chloride is 1:2, the yield and selectivity of 1,2-aceanthrylenedione is 83.8 % and 92.3% respectively.

  1. SYNTHESIS OF 1,2-ACEANTHRYLENEDIONE THROUGH ACYLATION OF ANTHRACENE WITH OXALYL CHLORIDE

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Acylation of anthracene and oxalyl chloride in the presence of anhydrous AlCl3 was investigated. Pure 1,2-aceanthrylenedione, which is used as new functional macromolecule, was prepared by extraction and recrystallation. The structure of 1,2-aceanthrylenedione was identified by measure of melting point, GC/MS, FTIR and 1HNMR analyses. The influences of various parameters, such as solvent, dosage of catalyst, molar ratio of anthracene to oxalyl chloride, reaction temperature, and reaction time were studied. The anhydrous AlCl3 was found to catalyze the reaction with high yeild and good selectivity. When the reaction temperature is 303K, reaction time is 5h and molar ratio of anthracene to oxalyl chloride is 1:2, the yield and selectivity of 1,2-aceanthrylenedione is 83.8 % and 92.3% respectively.

  2. Fluorescence quenching of anthracene by N, N-diethylaniline in the O/W microemulsion

    Institute of Scientific and Technical Information of China (English)

    郭霞; 徐慧; 郭荣

    2000-01-01

    Photoinduced electron-transfer system of anthracene-N , N-di-ethylaniline (DEA) was studied in the oil in water (O/W) microemulsuins formed by SDS (sodium dodecyl sulfate), BA(benzyl alcohol) and H2O. The time-resolved fluorescence study showed that the fluorescence quenching of the excited anthracene by DEA occurs at the interface of the O/W micreomulsions Besides as the quencher of the excited anthrace ne, N, N-diethylaniine could act as a cosurfactant to change the structures of the microemulsions, just as BA did. The quenching rate constants for the different structures of the system were determined.

  3. (E)-Methyl 3-(10-bromo­anthracen-9-yl)acrylate

    OpenAIRE

    Bernhard Bugenhagen; Yosef Al Jasem; Bassam al Hindawi; Nathir Al Rawashdeh; Thies Thiemann

    2013-01-01

    In the title molecule, C18H13BrO2, the anthracene unit forms an angle of 46.91 (2)° with the mean plane of the methyl acrylate moiety. In the crystal, the molecules arrange themselves into strands parallel to [010] and, due to the crystal symmetry, there are eight strands crossing the unit cell. In each strand, molecules form short C—H...O and C—H...π contacts and have their anthracene groups parallel to each other. Neighboring strands, related by a c-glide operati...

  4. Growth of optical-quality anthracene crystals doped with dibenzoterrylene for controlled single photon production

    International Nuclear Information System (INIS)

    Dibenzoterrylene (DBT) molecules within a crystalline anthracene matrix show promise as quantum emitters for controlled, single photon production. We present the design and construction of a chamber in which we reproducibly grow doped anthracene crystals of optical quality that are several mm across and a few μm thick. We demonstrate control of the DBT concentration over the range 6–300 parts per trillion and show that these DBT molecules are stable single-photon emitters. We interpret our data with a simple model that provides some information on the vapour pressure of DBT

  5. Synthesis, crystal structures and photoluminescence of anthracen- and pyrene-based coumarin derivatives.

    Science.gov (United States)

    Zhang, Hui; Tong, Hao; Zhao, Yuling; Yu, Tianzhi; Zhang, Peng; Li, Jianfeng; Fan, Duowang

    2015-11-01

    Two new anthracen- and pyrene-based coumarin derivatives, 3-(4-(anthracen-10-yl)phenyl)coumarin (4) and 3-(4-(pyrene-1-yl)phenyl)coumarin (5), were synthesized and characterized by FT-IR, (1)H NMR, element analysis and single crystal X-ray crystallography. The UV-vis absorption and photoluminescence spectra of these coumarin derivatives were investigated. The results show that compound 4 and 5 exhibit blue and blue-green emissions, respectively, under ultraviolet light excitation. Compared with the compound 4, the emission peak of compound 5 was bathochromically shifted by about 80 nm due to the more planar structure and larger π-conjugation.

  6. Synthesis and electroluminescent properties of anthracene derivatives containing electron-withdrawing oxide moieties

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jhin-yeong; Na, Eun Jae; Park, Soo Na [Department of Chemistry, Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of); Lee, Seok Jae [Department of Information Display, Hongik University, Seoul, 121-791 (Korea, Republic of); Kim, Young Kwan, E-mail: kimyk@wow.hongik.ac.kr [Department of Information Display, Hongik University, Seoul, 121-791 (Korea, Republic of); Yoon, Seung Soo, E-mail: ssyoon@skku.edu [Department of Chemistry, Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of)

    2014-10-15

    Highlights: • Blue fluorescent material is important for application in full-color displays. • We have synthesized emitters based on anthracene connected with oxide moieties. • 1C shows a highly efficient blue EL emission due to electron-injection property. - Abstract: A series of new blue-emitting materials: (4-(10-(naphthalen-2-yl)anthracen-9-yl)phenyl)(phenyl)methanone (1); 9-(naphthalen-2-yl)-10-(4-((diphenyl)phosphine oxide)phenyl)anthracene (2); 9-(naphthalen-2-yl)-10-(4-(phenylsulfonyl)phenyl)anthracene (3) were designed and synthesized via Suzuki cross-coupling reaction. Multilayer OLEDs were fabricated in the following sequence: ITO (180 nm)/NPB (50 nm)/blue materials 1–3 (30 nm)/TPBi (15 nm)/Liq (2 nm)/Al (100 nm). All devices showed the efficient blue EL emissions. In particular, the device using 1 as an emitter exhibited efficient blue electroluminescent properties with a maximum luminous, power, external quantum efficiency and CIE coordinates of 0.36 cd/A, 0.90 lm/W, 0.55% at 20 mA/cm{sup 2} and (x = 0.16, y = 0.20) at 10.0 V, respectively.

  7. Activation energies for fragmentation channels of anthracene dications : Experiment and theory

    NARCIS (Netherlands)

    Reitsma, G.; Zettergren, H.; Martin, S.; Bredy, R.; Chen, L.; Bernard, J.; Hoekstra, R.; Schlathölter, Thomas

    2012-01-01

    We have studied the fragmentation of the polycyclic aromatic hydrocarbon anthracene (C14H10) after double electron transfer to a 5 keV proton. The excitation energies leading to the most relevant dissociation and fission channels of the resulting molecular dication were directly determined experimen

  8. Exploiting anthracene photodimerization within peptides: light induced sequence-selective DNA binding.

    Science.gov (United States)

    Bullen, Gemma A; Tucker, James H R; Peacock, Anna F A

    2015-05-11

    The unprecedented use of anthracene photodimerization within a protein or peptide system is explored through its incorporation into a DNA-binding peptide, derived from the GCN4 transcription factor. This study demonstrates an effective and dynamic interplay between a photoreaction and a peptide-DNA assembly, with each process able to exert control over the other.

  9. Excimer-like electroluminescence from thin films of switchable supermolecular anthracene-based rotaxanes

    NARCIS (Netherlands)

    Giro, G.; Cocchi, M.; Fattori, V.; Gadret, G.; Ruani, G.; Murgia, M.; Cavallini, M.; Biscarini, F.; Zamboni, R.; Loontjens, T.; Thies, J.; Leigh, D.A.; Morales, A.F.

    2001-01-01

    Thin films of 10-[3,5-di(terbutyl)phenoxy]decyl-2-({2-[(9-anthrylcarbonyl)amino]acetyl}amino) acetate (ANTPEP), the thread of an anthracene-based rotaxane, have been processed by the spin coating technique in a polycarbonate (PC) matrix. A single layer organic light emitting diode (OLED) has been de

  10. Synthesis of pentacyclic 13-azadibenzo[a,de]anthracenes via anionic cascade ring closure

    DEFF Research Database (Denmark)

    Kristensen, Jesper Langgaard; Vedsø, P.; Begtrup, M.

    2003-01-01

    Bromine-lithium exchange using tert-butyllithium at -78 °C initiates a cascade process whereby either xanthone derivatives or pentacyclic 13-azadibenzo[a,de]anthracenes are produced in high yields. The reaction proceeds via a sequential intramolecular trapping of organolithium intermediates....

  11. Efficient laser desorption ionization mass spectrometry of polycyclic aromatic hydrocarbons using excitation energy transfer from anthracene

    International Nuclear Information System (INIS)

    Highlights: ► Femtomolar detection of PAHs such as perylene and benzopyrene was achieved. ► Photoexcited anthracene molecules transferred their energy to PAHs. ► Electronically excited PAHs were then excited to be ions. ► Two-photon ionization process was necessary to complete the ionization process. ► The number of defect sites could be reduced by the annealing procedure. - Abstract: Polycyclic aromatic hydrocarbons (PAHs), such as perylene and benzopyrene, doped at amounts on the order of femtomol (∼10−15 mol) in anthracene crystals could be detected by laser desorption ionization mass spectrometry. Sensitivity was roughly 103 times higher than that of LDI method in our experimental conditions. It was revealed from the excitation power dependence of the peak intensity of PAHs on the mass spectra that two-photon excitation in one UV pulse was necessary to complete the ionization process. It was also clarified that the number of defect sites that trap excitons generated in anthracene crystals could be reduced by the annealing procedure, by which an efficient energy transfer between anthracene and PAHs became possible

  12. N-[(E-Anthracen-9-ylmethylidene]-3,4-dimethyl-1,2-oxazol-5-amine

    Directory of Open Access Journals (Sweden)

    Abdullah M. Asiri

    2011-12-01

    Full Text Available In the title compound, C20H16N2O, an intramolecular C—H...N forms an S(6 ring motif. In the crystal, the molecules are stacked with their anthracene ring planes in sheets along [100].

  13. Design and electrical characterization of Au/Anthracene/p-Si/Al organic/inorganic heterojunction

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ghamdi, Attieh A., E-mail: aaaalghamdi4@kau.edu.sa [Center of Nanotechnology, King Abdulaziz University, Department of Physics, North Jeddah (Saudi Arabia); Nawar, Ahmed M.; El-Tantawy, Farid [Department of Physics, Faculty of Science, Suez Canal University, Ismailia (Egypt); Yaghmour, S.J. [Department of Physics, King Abdulaziz University, North Jeddah (Saudi Arabia); Azam, Ameer [Center of Nanotechnology, King Abdulaziz University, Department of Physics, North Jeddah (Saudi Arabia)

    2015-02-15

    Highlights: • We have successfully fabricated a Au/Anthracene/p-Si/Al organic/inorganic heterojunction. • The calculated series resistance and the shunt resistance of the device were found to be 440 Ω and 1.47 MΩ, respectively. • The Cheung-Cheung and Norde’s models were used to investigate and determine the heterojunction parameters. • Essential junction parameters and performance of heterojunction established a photovoltaic behavior. • Open circuit voltage (V{sub oc}) 0.382 V, short circuit photocurrent (I{sub SC}) 0.72 mA and power conversion efficiency (η) of 4.65%. - Abstract: Hybrid organic/inorganic heterojunction of nanocrystalline Anthracene and p-Si was fabricated by using a conventional thermal evaporation technique. The crystal and molecular structure of the Anthracene thin films were analyzed by means of X-ray diffraction (XRD), and Fourier Transformation-Infra Red (FT-IR) spectroscopy. The morphologies of the Anthracene/p-Si were investigated by scanning electron microscopy (SEM). The dark current-voltage (I-V) characteristics of Au/Anthracene/p-Si/Al heterojunction were investigated at room temperature (293 K). The calculated series resistance and the shunt resistance of the device were found to be 440 Ω and 1.47 MΩ, respectively. The Cheung-Cheung and Norde’s models were used to investigate and determine the heterojunction parameters. The ideality factor and barrier height values of the Au/Anthracene/p-Si/Al diode were obtained to be 1.1 and 0.464 eV, respectively. The dependence of capacitance-voltage (C{sup -2}-V) for the device Anthracene/p-Si was found to be almost linear. Essential junction parameters and performance of heterojunction established a photovoltaic behavior with an open circuit voltage (V{sub oc}) 0.382 V, short circuit photocurrent (I{sub SC}) 0.72 mA and power conversion efficiency (η) of 4.65%.

  14. Flocculant in wastewater affects dynamics of inorganic N and accelerates removal of phenanthrene and anthracene in soil.

    Science.gov (United States)

    Fernandez-Luqueno, F; Thalasso, F; Luna-Guido, M L; Ceballos-Ramírez, J M; Ordoñez-Ruiz, I M; Dendooven, L

    2009-06-01

    Recycling of municipal wastewater requires treatment with flocculants, such as polyacrylamide. It is unknown how polyacrylamide in sludge affects removal of polycyclic aromatic hydrocarbons (PAH) from soil. An alkaline-saline soil and an agricultural soil were contaminated with phenanthrene and anthracene. Sludge with or without polyacrylamide was added while emission of CO(2) and concentrations of NH(4)(+), NO(3)(-), NO(2)(-), phenanthrene and anthracene were monitored in an aerobic incubation experiment. Polyacrylamide in the sludge had no effect on the production of CO(2), but it reduced the concentration of NH(4)(+), increased the concentration of NO(3)(-) in the Acolman soil and NO(2)(-) in the Texcoco soil, and increased N mineralization compared to the soil amended with sludge without polyacrylamide. After 112d, polyacrylamide accelerated the removal of anthracene from both soils and that of phenanthrene in the Acolman soil. It was found that polyacrylamide accelerated removal of phenanthrene and anthracene from soil.

  15. Well-defined Polymethylene-Based Co/Terpolymers by Combining Anthracene/Maleimide Diels-Alder Reaction with Polyhomologation

    KAUST Repository

    Hadjichristidis, Nikolaos

    2015-05-26

    A novel strategy towards well-defined polymethylene-based co/terpolymers, by combining anthracene/maleimide Diels-Alder reaction with polyhomologation, is presented. For the synthesis of diblock copolymers the following approach was applied: a) synthesis of α-anthracene-ω-hydroxy- polymethylene by polyhomologation using tri (9-anthracene-methyl propyl ether) borane as initiator, b) synthesis of furan-protected-maleimide-terminated poly (ε-caprolactone) or polyethylene glycol and c). Diels-Alder reaction between the anthracene and maleimide-terminated polymers. In the case of triblock terpolymers the α-anthracene-ω-hydroxy-polymethylene was used as macroinitiator for the ring-opening polymerization of D, L-lactide to afford an anthracene-terminated PM-b-PLA copolymer, followed by Diels-Alder reaction with furan-protected maleimide-terminated poly (ε-caprolactone) or polyethylene glycol to give the triblock terpolymers. All intermediate and final products were characterized by SEC, 1H NMR, UV-VIS spectroscopy and DSC.

  16. Molecular dynamics of dibenz[a,h]anthracene and its metabolite interacting with lung surfactant phospholipid bilayers.

    Science.gov (United States)

    Padilla-Chavarría, Helmut I; Guizado, Teobaldo R C; Pimentel, Andre S

    2015-08-28

    The interaction of dibenz[a,h]anthracene and its ultimate carcinogenic 3,4-diol-1,2-epoxide with lung surfactant phospholipid bilayers was successfully performed using molecular dynamics. The DPPC/DPPG/cholesterol bilayer (64 : 64 : 2) was used as the lung surfactant phospholipid bilayer model and compared with the DPPC bilayer as a reference. Dibenz[a,h]anthracene and its 3,4-diol-1,2-epoxide were inserted in water and lipid phases in order to investigate their interactions with the lung surfactant phospholipid bilayers. The radial distribution function between two P atoms in polar heads shows that the 3,4-diol-1,2-epoxide affects the order between the P atoms in the DPPC/DPPG/cholesterol model more than dibenz[a,h]anthracene, which is a consequence of its preference for the polar heads and dibenz[a,h]anthracene prefers to be located in the hydrocarbon chain of the phospholipid bilayers. Dibenz[a,h]anthracene and its 3,4-diol-1,2-epoxide may form aggregates in water and lipid phases, and in the water-lipid interface. The implications for the possible effect of dibenz[a,h]anthracene and its 3,4-diol-1,2-epoxide in the lung surfactant phospholipid bilayers are discussed.

  17. Monitoring cellular uptake and cytotoxicity of copper(II) complex using a fluorescent anthracene thiosemicarbazone ligand.

    Science.gov (United States)

    Kate, Anup N; Kumbhar, Anupa A; Khan, Ayesha A; Joshi, Pranaya V; Puranik, Vedavati G

    2014-01-15

    The thiosemicarbazone derivative of anthracene (ATSC, anthracene thiosemicarbazone 1) and its copper(II) complex (CuATSC, 2) were synthesized and characterized by spectroscopic, electrochemical, and crystallographic techniques. Interaction of 1 and 2 with calf thymus (CT) DNA was explored using absorption and emission spectral methods, and viscosity measurements reveal a partial-intercalation binding mode. Their protein binding ability was monitored by the quenching of tryptophan emission using bovine serum albumin (BSA) as a model protein. Furthermore, their cellular uptake, in vitro cytotoxicity testing on the HeLa cell line, and flow cytometric analysis were carried out to ascertain the mode of cell death. Cell cycle analysis indicated that 1 and 2 cause cell cycle arrest in sub-G1 phase. PMID:24328322

  18. Research on Synthesizing Disperser with Fraction of Anthracene Oil for Coal Water Slurry

    Institute of Scientific and Technical Information of China (English)

    WU Guo-guang; GUO Zhao-bing; WU Jian-jun; XIE Qiang; WANG Xiao-chun

    2003-01-01

    Experiment of synthesizing a disperser for coal water slurry (CWS) by using fractions of anthracene oil from high-temperature coal tar was performed. The orthogonal test was used to investigate the influence of temperature, time, quantity of sulfonation agent and condensation agent and the interaction of these factors on properties of the disperser. The result shows that the influence of temperature, time, quantity of sulfonation agent and condensation agent, and the interaction of sulfonation time and sulfonation agent has a significant influence on the properties of disperser. The optimal condition of synthesis is that in 150g of the fractions of anthracene oil, 40 mL of sulfonation agent is added and sulfonated for 3 h at 130℃, then, 10 mL of condensing agent is added and condensated for 1.5 h at 115 ℃.

  19. Synthesis and Luminescent Property of Poly(9-(3-vinyl-phenyl)-anthracene).

    Science.gov (United States)

    Lee, Sunmi; Shin, Hwangyu; Park, Beom-Soo Michael; Lee, Jaehyun; Park, Jongwook

    2015-07-01

    Polymer light-emitting diodes (PLEDs) have attracted much attention from academia and industry field because of their various applications such as large area flat-panel displays and lightings. In this paper, we suggest new blue emitting polymer based on anthracene, Poly(9-(3-Vinyl-phenyl)-anthracene) (PVPA). From NMR data, vinyl group protons were disappeared and aromatic protons showed broad proton peaks because of polymer characteristics. PVPA had film property well and it exhibited vivid PL maximum values of 431, 455, 482 nm and broad PL spectrum. Three dopants for green, red, yellow were used to PVPA, all energy transfer was happened well. By using rubrene dopant of yellow emission, doped film provided white PL. PMID:26373155

  20. Diffusion of anthracene derivatives on Cu(111) studied by STM and DFT

    Science.gov (United States)

    Wyrick, Jonathan; Bartels, Ludwig; Einstein, Theodore

    2014-03-01

    Substituted anthracenes have drawn attention due to their ability to diffuse uniaxially on a Cu(111) surface. We compare anthracene to three of its derivatives whose 9,10 hydrogens are replaced by elements of the chalcogen group that act as linkers binding the molecules to a Cu(111) substrate. DFT calculations shed light on STM imaging and diffusion studies on the three substituted species. We present an analysis of the DFT results in which energetic contributions to the diffusion barriers are partitioned among the Kohn-Sham orbitals, allowing us to make assignments as to how each orbital affects diffusion for each species and draw comparisons between them. Present address: Center for Nanoscale Science and Technology, NIST, Gaithersburg, MD.

  1. Scintillation characteristics on anthracene-doped naphthalene crystal for 137Cs-γ ray source

    International Nuclear Information System (INIS)

    In this paper, we report scintillation characterizations on anthracene-doped naphthalene (NA) crystal. Crystals of this scintillator have been grown using the Bridgman-growth process. The peak of NA crystal emission is at 425 nm. The luminescence intensity of the NA crystal is 3 times that of pure naphthalene crystal. Naphthalene when doped with anthracene has high light output and fast principal decay constant (137Cs source), energy resolution of 18% (FWHM) has been recorded at room temperature for NA crystals coupled to a photomultiplier. The pulse height of NA is 10 times greater than the pure naphthalene crystal. The NA detector exhibited a good timing performance compared to trans-stilbene detector

  2. Scintillation characteristics on anthracene-doped naphthalene crystal for {sup 137}Cs-{gamma} ray source

    Energy Technology Data Exchange (ETDEWEB)

    Balamurugan, N. [Crystal Growth Centre, Anna University, Chennai 600025 (India); Arulchakkaravarthi, A. [Electrical Engineering Department, University of South Carolina, SC (United States); Ramasamy, P. [Crystal Growth Centre, Anna University, Chennai 600025 (India) and SSN College of Engineering, Kalavakkam 603110 (India)]. E-mail: pramasamy@annauniv.edu

    2006-12-01

    In this paper, we report scintillation characterizations on anthracene-doped naphthalene (NA) crystal. Crystals of this scintillator have been grown using the Bridgman-growth process. The peak of NA crystal emission is at 425 nm. The luminescence intensity of the NA crystal is 3 times that of pure naphthalene crystal. Naphthalene when doped with anthracene has high light output and fast principal decay constant (<30 ns). For 662 keV {gamma} rays ({sup 137}Cs source), energy resolution of 18% (FWHM) has been recorded at room temperature for NA crystals coupled to a photomultiplier. The pulse height of NA is 10 times greater than the pure naphthalene crystal. The NA detector exhibited a good timing performance compared to trans-stilbene detector.

  3. Inhibiting the photosensitized oxidation of anthracene and tryptophan by means of natural antioxidants

    Science.gov (United States)

    Aksenova, N. A.; Vyzhlova, E. N.; Malinovskaya, V. V.; Parfenov, V. V.; Solov'eva, A. B.; Timashev, P. S.

    2013-08-01

    It is shown that model reactions of photosensitized oxidation of anthracene and tryptophan can be used for evaluation and comparison of antioxidant activity of various classes of compounds. Inhibition of the oxidation of substrates in the presence of the familiar antioxidants tocopherol (vitamin E), ascorbic acid (vitamin C), and mixtures of these vitamins with methionine, and in the presence of reputed antioxidants dihydroquercetin and taurine, are considered. It is concluded that all of the above compounds except for taurine have antioxidant properties; i.e., they reduce the rate constants of the photosensitized oxidation of anthracene and tryptophan. It is found that the inhibition of oxidation is associated with the interaction between antioxidants and singlet oxygen. Analysis of the kinetic dependences of the photosensitized oxidation of substrates in the presence of antioxidants reveals that a mixture of vitamins inhibits the process most efficiently, and inhibition occurs at the initial stages due to more active interaction between singlet oxygen and vitamin C

  4. A molecular dynamics study on slow ion interactions with the polycyclic aromatic hydrocarbon molecule anthracene

    International Nuclear Information System (INIS)

    Atomic collisions with polycyclic aromatic hydrocarbon (PAH) molecules are astrophysically particularly relevant for collision energies of less than 1 keV. In this regime, the interaction dynamics are dominated by elastic interactions. We have employed a molecular dynamics simulation based on analytical interaction potentials to model the interaction of low energy hydrogen and helium projectiles with isolated anthracene (C14H10) molecules. This approach allows for a very detailed investigation of the elastic interaction dynamics on an event by event basis. From the simulation data the threshold projectile kinetic energies above which direct C atom knock out sets in were determined. Anthracene differential energy transfer cross sections and total (dissociation) cross sections were computed for a wide range of projectile kinetic energies. The obtained results are interpreted in the context of PAH destruction in astrophysical environments.

  5. Discovery of novel dihydro-9,10-ethano-anthracene carboxamides as glucocorticoid receptor modulators.

    Science.gov (United States)

    Yang, Bingwei V; Vaccaro, Wayne; Doweyko, Arthur M; Doweyko, Lidia M; Huynh, Tram; Tortolani, David; Nadler, Steven G; McKay, Lorraine; Somerville, John; Holloway, Deborah A; Habte, Sium; Weinstein, David S; Barrish, Joel C

    2009-04-15

    A series of dihydro-9,10-ethano-anthracene-11-carboxamides as novel glucocorticoid receptor modulators is reported. SAR exploration identified compounds from this series displaying a promising dissociation profile in discriminating between transrepression and transactivation activities. 17a is a partial agonist of GR-mediated transactivation which elicits potent and efficacious transrepression in reporter gene assays. A hypothetical binding mode is provided which accounts for the induction of functional activity by a bridgehead methyl group. PMID:19321341

  6. Crystal structure of [(1,2,3,4,11,12-η-anthracene]tris(trimethylstannylcobalt(III

    Directory of Open Access Journals (Sweden)

    William W. Brennessel

    2014-11-01

    Full Text Available The asymmetric unit of the title structure, [Co(η6-C14H10{Sn(CH33}3], contains two independent molecules. Each anthracene ligand is η6-coordinating to a CoIII cation and is nearly planar [fold angles of 5.4 (3 and 9.7 (3°], as would be expected for its behaving almost entirely as a donor to a high-oxidation-state metal center. The slight fold in each anthracene ligand gives rise to slightly longer Co—C bond lengths to the ring junction carbon atoms than to the other four. Each CoIII cation is further coordinated by three Sn(CH33 ligands, giving each molecule a three-legged piano-stool geometry. In each of the two independent molecules, the trio of SnMe3 ligands are modeled as disordered over two positions, rotated by approximately 30%, such that the C atoms nearly overlap. In one molecule, the disorder ratio refined to 0.9365 (8:0.0635 (8, while that for the other refined to 0.9686 (8:0.0314 (8. The molecules are well separated, and thus no significant intermolecular interactions are observed. The compound is of interest as the first structure report of an η6-anthracene cobalt(III complex.

  7. Hydrogenation of Anthracene in Supercritical Carbon Dioxide Solvent Using Ni Supported on Hβ-Zeolite Catalyst

    Directory of Open Access Journals (Sweden)

    Ashraf Aly Hassan

    2012-01-01

    Full Text Available Catalytic hydrogenation of anthracene was studied over Ni supported on Hβ-zeolite catalyst under supercritical carbon dioxide (sc-CO2 solvent. Hydrogenation of anthracene in sc-CO2 yielded 100% conversion at 100 °C, which is attributed to the reduced mass transfer limitations, and increased solubility of H2 and substrate in the reaction medium. The total pressure of 7 MPa was found to be optimum for high selectivity of octahydroanthracene (OHA. The conversion and selectivity for OHA increased with an increase in H2 partial pressure, which is attributed to higher concentration of hydrogen atoms at higher H2 pressures. The selectivity reduced the pressure below 7 MPa because of enhanced desorption of the tetrahydro-molecules and intermediates from Ni active sites, due to higher solubility of the surface species in sc-CO2. The selectivity of OHA increased with the increase in catalyst weight and reaction time. The rate of hydrogenation of anthracene was compared with that found for napthalene and phenanthrene. The use of acetonitrile as co-solvent or expanded liquid with CO2 decreased the catalytic activity.

  8. Semiconducting Polymers Consisting of Anthracene and Benzotriazole Units for Organic Solar Cells.

    Science.gov (United States)

    Shin, Seung Ah; Kim, Ji-Hoon; Park, Jong Baek; Hwang, Do-Hoon

    2015-02-01

    An alternating copolymer composed of 2,6-dibromo-9,10-bis(2-ethylhexyloxy)anthracene and benzotriazole units, poly(An-alt-BTz), was synthesized, through a Suzuki cross-coupling polymerization, for use in photovoltaic devices as a p-type electron donor. For the reduction of the bandgap energy of benzotriazole units, 5,5'-dibromo-2,2'-bithiophene, or 2,5-dibromothieno [3,2-b] thiophene units were introduced into the polymer. Poly(anthracene-co-benzotriazole-co-bithiophene(thienothiophene))s were synthesized using the same polymerization reactions. The measured optical bandgap energy of poly(anthracene-alt-benzotriazole) was 2.62 eV. As the contents of the flat comonomer units in the ter-polymers increased, the bandgap energies of the resulting polymers decreased up to 1.95 eV. The energy levels of the HOMO and the LUMO of the copolymers were determined from the cyclic voltammetry. Photovoltaic devices were fabricated with the polymers as electron donors and PC71 BM as an electron acceptor. One of the fabricated devices showed the maximum PCE of 0.74% with 0.57 V of VOC, 2.59 mA/cm2 of JSC, and 0.48 of FF under AM 1.5G (100 mW/cm2) condition. PMID:26353683

  9. Antioxidant Potential of Anthrarobin (1, 2, 10 trihydroxy anthracene) and its Acyl Derivatives

    International Nuclear Information System (INIS)

    The current study explores the antioxidant potential of anthrarobin and its synthesized derivatives determined by various methods including DPPH radical scavenging ability, reducing power and superoxide scavenging activity. Anthrarobin was acetylated with acetic anhydride in the presence of pyridine to afford anthracen-1, 10-dihydroxy-2-acetate (1), anthracen-1-hydroxy-2, 10-diacetate (2) and anthracen-1, 2, 10-triacetate (3). Anthrarobin exhibited good antioxidant potential with 68 and 78% at 50 meuM and 100 meuM concentrations, respectively. Reducing power of anthrarobin increases with increase in concentration in a dose-dependent manner as could be seen from 37 and 54% activity at the concentration of 50 and 100 meuM, respectively. 3-Tetra-butyl-4-hydroxyanisole (BHA) used as standard showed 84 and 93% activities at 50 and 100 meuM, respectively. BHA and anthrarobin were compared to determine that how much superoxide radicals were scavenged in alkaline DMSO by different concentrations. It was found that 50 meuM of anthrarobin was needed to scavenge 50% radicals while 12.5 meuM of BHA scavenged 50% radicals in DMSO. It is concluded that anthrarobin has highest antioxidant potential as compared to its derivatives. It is postulated that position and numbers of hydroxyl group in anthrarobin are responsible for antioxidant potential and the activity decreases with the substitution of acyl groups at various positions in synthesized derivatives. (author)

  10. Picosecond ion-pair dynamics following CT excitation of EDA complexes of tetranitromethane with anthracene

    Energy Technology Data Exchange (ETDEWEB)

    Han, Chul Hee [Sun Moon University, Asan (Korea, Republic of)

    1995-11-15

    It was well known that CT (Charge Transfer band) excitation of EDA (Electron Donor Acceptor) complex of Aromatic compound and Tetranitromethane (TNM) produces covalent adduct as the final product; however, it was not until the picosecond study on the Anthracene EDA complexes with Tetranitromethane that the dynamics associated with the covalent adduct formation and other related processes became quantitatively evaluated. According to the current understanding of the subject, picosecond excitation of EDA complex produces Contact Ion Pair (CIP) instantaneously, and this CIP is subject to two main competing processes; Ion-Pair collapse to form a covalent adduct and separation by solvent to form solvent separated Ion Pair (SSIP). In addition to these processes, Ion-pair exchange is possible with the added salt such as Tetra-n-butylammoniumperchlorate (TBA{sup +}P{sup -}) or Tetra-n-butyl-ammonium trinitromethide (TBA{sup +}T{sup -}). Previous picosecond study on the Anthracene EDA complexes with TNM employed a series of 9-X-anthracenes, where the substituents (X) of varying electrophilic character were used to modulate the ion-pair dynamics in various solvent with or without the added salts. Their work on the solvent effect and salt effect has revealed the importance of the ionic character of CIP in its solution dynamics.

  11. Picosecond ion-pair dynamics following CT excitation of EDA complexes of tetranitromethane with anthracene

    International Nuclear Information System (INIS)

    It was well known that CT (Charge Transfer band) excitation of EDA (Electron Donor Acceptor) complex of Aromatic compound and Tetranitromethane (TNM) produces covalent adduct as the final product; however, it was not until the picosecond study on the Anthracene EDA complexes with Tetranitromethane that the dynamics associated with the covalent adduct formation and other related processes became quantitatively evaluated. According to the current understanding of the subject, picosecond excitation of EDA complex produces Contact Ion Pair (CIP) instantaneously, and this CIP is subject to two main competing processes; Ion-Pair collapse to form a covalent adduct and separation by solvent to form solvent separated Ion Pair (SSIP). In addition to these processes, Ion-pair exchange is possible with the added salt such as Tetra-n-butylammoniumperchlorate (TBA+P-) or Tetra-n-butyl-ammonium trinitromethide (TBA+T-). Previous picosecond study on the Anthracene EDA complexes with TNM employed a series of 9-X-anthracenes, where the substituents (X) of varying electrophilic character were used to modulate the ion-pair dynamics in various solvent with or without the added salts. Their work on the solvent effect and salt effect has revealed the importance of the ionic character of CIP in its solution dynamics.

  12. Usefulness of a Technique Based on Negative Corona Discharge for the Degradation of Selected, Condensed PAHs: Application to the Oxidation of Anthracene and Similar Structures

    OpenAIRE

    Tessier, D.; OGUIC, C.; PINART, J.

    2001-01-01

    The usefulness of negative corona discharge for oxidation of condensed polycyclic aromatic hydrocarbons (PAHs), including anthracene, naphthalene and 2,3-benzanthracene, adsorbed on a solid substrate is evaluated. In the case of anthracene, the application of corona discharge under high voltage (10-20 kV) for 10 to 180 min with a current intensity of 5-120 m A in a controlled, humid atmosphere leads to the progressive formation of anthraquinone. A kinetic study of the anthracene o...

  13. A new family of donor-acceptor systems comprising tin(IV) porphyrin and anthracene subunits: Synthesis, spectroscopy and energy transfer studies

    Indian Academy of Sciences (India)

    A Ashok Kumar; L Giribabu; Bhaskar G Maiya

    2002-12-01

    A new family of covalently linked `Sn(IV) porphyrin-anthracene’ diad (1), triad (2) and tetrad (3) donor-acceptor (D-A) systems have been designed and synthesized in good-to-moderate yields. While diad 1 possesses one anthracene subunit at the peripheral (meso) position of the tin(IV) porphyrin scaffold, triad 2 possesses two trans axial anthracene subunits at the tin(IV) centre. On the other hand, tetrad 3 is endowed with both the peripheral and axial anthracene subunits in its architecture. These D-A systems have been fully characterised by elemental analysis, FAB-MS, UV-Vis, 1H and 13C NMR and electrochemical methods. UV-Vis, NMR and redox data suggest the absence of intramolecular - interaction between the porphyrin and the anthracene/s in 1-3. Fluorescence from the anthracene subunit in 1 and 3 is found to be quenched in comparison with the fluorescence of free anthracene in four different solvents. This is not the case with compound 2. Excitation spectral data provides evidence for an intramolecular excitation energy transfer (EET) from the singlet anthracene to the porphyrin in 1 and 3. The energy transfer efficiency is in the order: 2 (almost negligible) < 3 (∼ 30%) < 1 (nearly quantitative), with the peripheral anthracene → porphyrin pathway being largely favoured. This orientation dependence of EET could be analysed using Forster’s dipole dipole mechanism.

  14. Generation of Renewable Power from Biodegradation of Anthracene in a Microbial Fuel Cell Reactor Using Different Bacterial Inocula

    Directory of Open Access Journals (Sweden)

    A.N.Z. Alshehri

    2015-06-01

    Full Text Available Microbial fuel cells (MFCs are increasingly attracting attention as a sustainable technology as they convert chemical energy in organic pollutants to renewable electricity. Anthracene is a polycyclic aromatic hydrocarbon (PAH that presents a high pollution and health risk. In this study, anthracene degradation with electricity production in Single – chamber air cathode MFC was investigated with respect to values of its biodegradation and MFC performance using different inocula combinations (Anaerobic sludge (AS, Pseudomonas putida (PP, Geobacter sulfurreducens (GS, Shewanella putrefaciens(SP, mixed cultures, and combinations thereof. All the inocula showed high potentials for anthracene degradation efficiency and power density, ranged 41 – 98 % within 120 – 216h and 110.08 – 156.06 mW/m2, respectively. The best overall performing inoculum was anaerobic sludge supplemented with P. putida (AS+PP, having a degradation rate, degradation efficiency, COD removal, maximum power density and coulombic efficiency of 38 μM/d, 98 %, 83 %, 156.06 mW/m2 and 21, respectively. Effect of initial anthracene concentration was also investigated. Results indicated that increasing of initial anthracene concentration to 40 mg/L has a positive effect on both the anthracene degradation rate and the power density by 79 and 83.93 %, respectively, which attained by the best inoculum AS+PP (degradation rate of 41 μM/d and a maximum power density of 287.04 mW/m2.This study highlights the possibility of using MFCs technology to generate renewable electricity and achieve high degradation rates of anthracene simultaneously, through co-metabolism.

  15. Novel anthracene-based fluorescent sensor for selective recognition of acetate anions in protic media

    Science.gov (United States)

    Xu, Kuoxi; Kong, Huajie; Li, Qian; Song, Pan; Dai, Yanpeng; Yang, Li

    2015-02-01

    Novel 9-substituted anthracene derivatives were synthesized and characterized by IR, HRMS, 1H and 13C NMR. The fluorescence titration experiments were explored to study the interaction between the compounds and some anions, such as H2PO4-, P2O74-, F-, Cl-, Br-, I-, AcO- in H2O (0.01 M HEPES, pH = 7.4) under imitated physiological conditions. One of these compounds, bearing a phenylalaninol unit, showed specific fluorescence enhancement with acetate anion. The sensor L1 was found to present good selective fluorescence sensing ability to acetate anion through photoinduced electron-transfer mechanism in protic media.

  16. White organic light-emitting diodes with 9, 10-bis (2-naphthyl) anthracene

    Energy Technology Data Exchange (ETDEWEB)

    Guan Yunxia; Niu Lianbin [Key Laboratory of Optical Engineering, College of Physics and Information Technology, Chongqing Normal University, Chongqing 400047 (China)], E-mail: gyxybsy@126.com, E-mail: niulb03@126.com

    2009-03-01

    White organic light-emitting diodes were fabricated by 9, 10-bis (2-naphthyl) anthracene (ADN) doped with Rubrene with a structure of ITO/copper phthalocyanine (CuPc) / NPB /ADN: Rubrene /Alq{sub 3} /CsF/Mg:Ag/Ag. Multilayer organic devices using AND and Rubrene as an emitting layer produced white emissions with good chromaticity and luminous efficiency as high as 5.93 cd/A. This performance can be explained by Foerster energy transfer from the blue-emitting host to the orange-emitting dopant.

  17. Bioastrophysical Aspects of Low Energy Ion Irradiation of Frozen Anthracene Containing Water

    Energy Technology Data Exchange (ETDEWEB)

    Tuleta, M.; Gabla, L.; Madej, J.

    2001-08-13

    The origin of life on Earth remains a fascinating mystery in spite of many theories existing on this subject. However, it seems that simple prebiotic molecules could play an essential role in the formation of more complex organisms. In our experiment, we synthesized a class of these molecules (quinones) bombarding frozen anthracene containing water with low energy hydrogen ions. This experiment roughly simulated the astrophysical conditions which one can find in the solar system. Thus, we can hypothesize that prebiotic molecules could be created by interaction of the solar wind with interplanetary dust grains. The delivery of these molecules to early Earth may have contributed to the generation of life on our planet.

  18. (E)-1-(4-Meth-oxy-anthracen-1-yl)-2-phenyl-diazene.

    Science.gov (United States)

    Crochet, Aurelien; Fromm, Katharina M; Kurteva, Vanya; Antonov, Liudmil

    2011-04-01

    The title compound, C(21)H(16)N(2)O, has an E-conformation about the diazene N=N bond. It is reasonably planar with the phenyl ring being inclined to the mean plane of the anthracene moiety [planar to within 0.077 (3) Å] by 6.43 (10)°. The crystal structure is stabilized by C-H⋯π and weak π-π inter-actions [centroid-centroid distances of 3.7192 (16) and 3.8382 (15) Å], leading to the formation of two-dimensional networks stacking along [001] and lying parallel to (110).

  19. Bioastrophysical Aspects of Low Energy Ion Irradiation of Frozen Anthracene Containing Water

    International Nuclear Information System (INIS)

    The origin of life on Earth remains a fascinating mystery in spite of many theories existing on this subject. However, it seems that simple prebiotic molecules could play an essential role in the formation of more complex organisms. In our experiment, we synthesized a class of these molecules (quinones) bombarding frozen anthracene containing water with low energy hydrogen ions. This experiment roughly simulated the astrophysical conditions which one can find in the solar system. Thus, we can hypothesize that prebiotic molecules could be created by interaction of the solar wind with interplanetary dust grains. The delivery of these molecules to early Earth may have contributed to the generation of life on our planet

  20. New 1,4-anthracene-9,10-dione derivatives as potential anticancer agents.

    Science.gov (United States)

    Zagotto, G; Supino, R; Favini, E; Moro, S; Palumbo, M

    2000-01-01

    The amino-substituted anthracene-9,10-dione (9,10-anthraquinone) derivatives represent one of the most important classes of potential anticancer agents. To better understand the basic rules governing DNA sequence specificity, we have recently synthesized a new class of D- and L-aminoacyl-anthraquinone derivatives. We have tested these new compounds as cytotoxic agents, and we have correlated their activity with the configuration of the chiral aminoacyl moiety. Molecular modeling studies have been performed to compare the test drugs in terms of steric overlapping. PMID:10755224

  1. Towards nanoprobes for conduction in molecular crystals: Dibenzoterrylene in anthracene crystals

    International Nuclear Information System (INIS)

    The miniaturization of electronic devices and structures brings along the quest for instruments that operate on mesoscopic and nanometric scales. In these structures, nano-instruments could elucidate the rich variety of physical processes, an understanding of which will be necessary to develop and to predict the function of new nanoscale devices. For this purpose, we propose to use single molecules as nanoprobes and to address the probes individually by means of optical single molecule microscopy and spectroscopy. This would allow us to study the conduction in molecular crystals. Here, we compare different material systems and show that dibenzoterrylene in an anthracene crystal is a promising candidate system

  2. A panchromatic anthracene-fused porphyrin sensitizer for dye-sensitized solar cells

    KAUST Repository

    Ball, James M.

    2012-01-01

    The development of ruthenium-free sensitizers which absorb light over a broad range of the solar spectrum is important for improving the power conversion efficiency of dye-sensitized solar cells. Here we study three chemically tailored porphyrin-based dyes. We show that by fusing the porphyrin core to an anthracene unit, we can extend the conjugation length and lower the optical gap, shifting the absorption spectrum into the near-infrared (NIR). All three dyes were tested in dye-sensitized solar cells, using both titanium dioxide and tin dioxide as the electron-transport material. Solar cells incorporating the anthracene-fused porphyrin dye exhibit photocurrent collection at wavelengths up to about 1100 nm, which is the longest reported for a porphyrin-based system. Despite extending the photon absorption bandwidth, device efficiency is found to be low, which is a common property of cells based on porphyrin dyes with NIR absorption. We show that in the present case the efficiency is reduced by inefficient electron injection into the oxide, as opposed to dye regeneration, and highlight some important design considerations for panchromatic sensitizers. © 2012 The Royal Society of Chemistry.

  3. Synthesis, characterization, optical and electrical properties of bis(phenylvinyl)anthracene-based polymers

    Science.gov (United States)

    Mansour, Nadia; Hriz, Khaled; Jaballah, Nejmeddine; Kreher, David; Majdoub, Mustapha

    2016-08-01

    A series of bis(phenylvinyl)anthracene-based polymers containing different lengths of polar ethylene glycol groups in the main chain (P1-3) were efficiently synthesized by Wittig polycondensation. These polymers are fully soluble in volatile solvents, which helped a lot to obtain high quality films. Moreover, these semi-conducting materials exhibited semi-crystalline morphology with relatively high glass transition temperature. In this article, the UV-visible absorption and fluorescence properties of P1-3 were studied consequently both in solution and as thin solid film: tan absorption-onset at 433 nm was observed and all these bis(phenylvinyl)anthracene-based polymers (P1-3) show a blue emission in solution, fluorescence quantum efficiencies being respectively 52% for P1, 75% for P2 and 67% for P3. In addition, the HOMO/LUMO energy levels were evaluated by cyclic voltammetry measurements and indicate a p-type semi-conducting materials. Finally, the electrical properties of P1-3 were investigated by recording current-tension characteristics and these experimental results were modeled by the current space-charge-limited (SCLC) mechanism.

  4. Formation and Stabilization of Environmentally Persistent Free Radicals Induced by the Interaction of Anthracene with Fe(III)-Modified Clays.

    Science.gov (United States)

    Jia, Hanzhong; Nulaji, Gulimire; Gao, Hongwei; Wang, Fu; Zhu, Yunqing; Wang, Chuanyi

    2016-06-21

    Environmentally persistent free radicals (EPFRs) are occasionally detected in Superfund sites but the formation of EPFRs induced by polycyclic aromatic hydrocarbons (PAHs) is not well understood. In the present work, the formation of EPFRs on anthracene-contaminated clay minerals was quantitatively monitored via electron paramagnetic resonance (EPR) spectroscopy, and surface/interface-related environmental influential factors were systematically explored. The obtained results suggest that EPFRs are more readily formed on anthracene-contaminated Fe(III)-montmorillonite than in other tested systems. Depending on the reaction condition, more than one type of organic radicals including anthracene-based radical cations with g-factors of 2.0028-2.0030 and oxygenic carbon-centered radicals featured by g-factors of 2.0032-2.0038 were identified. The formed EPFRs are stabilized by their interaction with interlayer surfaces, and such surface-bound EPFRs exhibit slow decay with 1/e-lifetime of 38.46 days. Transformation pathway and possible mechanism are proposed on the basis of experimental results and quantum mechanical simulations. Overall, the formation of EPFRs involves single-electron-transfer from anthracene to Fe(III) initially, followed by H2O addition on formed aromatic radical cation. Because of their potential exposure in soil and atmosphere, such clay surface-associated EPFRs might induce more serious toxicity than PAHs and exerts significant impacts on human health. PMID:27224055

  5. Coordination Complexes as Catalysts: The Oxidation of Anthracene by Hydrogen Peroxide in the Presence of VO(acac)[subscript 2

    Science.gov (United States)

    Charleton, Kimberly D. M.; Prokopchuk, Ernest M.

    2011-01-01

    A laboratory experiment aimed at students who are studying coordination chemistry of transition-metal complexes is described. A simple vanadyl acetylacetonate complex can be used as a catalyst in the hydrogen peroxide oxidation of anthracene to produce anthraquinone. The reaction can be performed under a variety of reaction conditions, ideally by…

  6. Confined growth of carbon nanoforms in one-dimension by fusion of anthracene rings inside the pores of MCM-41

    Science.gov (United States)

    Bosch-Navarro, Concha; Coronado, Eugenio; Martí-Gastaldo, Carlos; Amorós, Pedro

    2014-06-01

    We report a simple two-step procedure that uses anthracene, a cheap polyaromatic hydrocarbon with low melting point, as a molecular precursor to produce carbon nanoforms (CNFs). First, we describe the chemical synthesis of graphite from the fusion of anthracene rings at relatively low temperature (520 °C) followed by cyclodehydrogenation. Next, we extend this protocol to the synthesis of CNFs by confining the molecular precursor in a mesoporous host like MCM-41. The confined environment favors one-dimensional growth of CNFs with sizes controlled by the pores of the mesoporous host.We report a simple two-step procedure that uses anthracene, a cheap polyaromatic hydrocarbon with low melting point, as a molecular precursor to produce carbon nanoforms (CNFs). First, we describe the chemical synthesis of graphite from the fusion of anthracene rings at relatively low temperature (520 °C) followed by cyclodehydrogenation. Next, we extend this protocol to the synthesis of CNFs by confining the molecular precursor in a mesoporous host like MCM-41. The confined environment favors one-dimensional growth of CNFs with sizes controlled by the pores of the mesoporous host. Electronic supplementary information (ESI) available: Synthesis details, SEM and additional HR-TEM images, FT-IR spectra, EDAX microanalysis and pore distribution of loaded MCM41@anth. See DOI: 10.1039/c3nr06669j

  7. Molecular self-healing mechanisms between C60-fullerene and anthracene unveiled by Raman and two-dimensional correlation spectroscopy.

    Science.gov (United States)

    Geitner, R; Kötteritzsch, J; Siegmann, M; Fritzsch, R; Bocklitz, T W; Hager, M D; Schubert, U S; Gräfe, S; Dietzek, B; Schmitt, M; Popp, J

    2016-07-21

    The self-healing polymer P(LMA-co-MeAMMA) crosslinked with C60-fullerene has been studied by FT-Raman spectroscopy in combination with two-dimensional (2D) correlation analysis and density functional theory calculations. To unveil the molecular changes during the self-healing process mediated by the Diels-Alder equilibrium between 10-methyl-9-anthracenyl groups and C60-fullerene different anthracene-C60-fullerene adducts have been synthesized and characterized by time-, concentration- and temperature-dependent FT-Raman measurements. The self-healing process could be monitored via the C60-fullerene vibrations at 270, 432 and 1469 cm(-1). Furthermore, the detailed analysis of the concentration-dependent FT-Raman spectra point towards the formation of anthracene-C60-fullerene adducts with an unusual high amount of anthracene bound to C60-fullerene in the polymer film, while the 2D correlation analysis of the temperature-dependent Raman spectra suggests a stepwise dissociation of anthracene-C60-fullerene adducts, which are responsible for the self-healing of the polymer. PMID:27327116

  8. Uptake of 7,12-dimethylbenz(a)anthracene and benzo(a)pyrene in melanin-containing tissues

    Energy Technology Data Exchange (ETDEWEB)

    Roberto, A.; Larsson, B.S. [Uppsala Univ., Dept. of Pharmaceutical Biosciences, Div. of Toxicology, Uppsala (Sweden); Tjaelve, H. [The Swedish Univ. of Agricultural Sciences, Dept. of Pharmacology and Toxicology, Uppsala (Sweden)

    1996-08-01

    It is widely accepted that UV exposure is the main etiological factor for malignant melanoma. Epidemiologic studies, however, have indicated that also chemical carcinogens may be a risk factor for the disease. Polycyclic aromatic hydrocarbons such as 7,12-dimethylbenz(a)anthracene and benzo(a)pyrene represent an important class of carcinogenic chemicals. It is known that 7,12-dimethylbenz(a)anthracene can induce melanotic tumours in various animal species, and human melanocytes in culture have been found to be capable of metabolizing benzo(a)pyrene to its proximate carcinogen benzo(a)pyrene-7,8-diol. In the present study the disposition of {sup 14}C- and {sup 3}H-7,12-dimethylbenz(a)anthracene and {sup 14}C-benzo(a)pyrene was studied in pigmented and albino mice and Syrian golden hamsters by whole-body autoradiography. The results showed pronounced retention of label in the melanin-containing structures of the eyes and the hair follicles in the pigmented animals. The labelling of the corresponding structures in the albino animals was low. Additional experiments showed that 7,12-dimethylbenz(a)anthracene and benzo(a)pyrene as well as some of their metabolites are bound to melanin in vitro. The specific localization of the polycyclic aromatic hydrocarbons in pigmented tissues due to melanin affinity, combined with bioactivating capacity of melanocytes, suggest that these substances may play a role in the induction of malignant melanoma. (au).

  9. Quinoline-Substituted 10-(naphthalene-7-yl)anthracene Derivatives for Blue Fluorescent Organic Light-Emitting Diodes.

    Science.gov (United States)

    Kim, Chanwoo; Park, Soo Na; Lee, Seul Bee; Kim, Young Seok; Lee, Ho Won; Kim, Young Kwan; Yoon, Seung Soo

    2016-02-01

    In this study, we have designed and synthesized blue emitters based on quinoline-substituted 10-(naphthalene-7-yl)anthracene. Particularly, a material exhibited highly efficient blue electroluminescence with CIE coordinates of (0.15, 0.18). PMID:27433688

  10. Photochemical Reaction of 7,12-Dimethylbenz[a]anthracene (DMBA and Formation of DNA Covalent Adducts

    Directory of Open Access Journals (Sweden)

    Peter P. Fu

    2005-04-01

    Full Text Available DMBA, 7,12-dimethylbenz[a]anthracene, is a widely studied polycyclic aromatic hydrocarbon that has long been recognized as a probable human carcinogen. It has been found that DMBA is phototoxic in bacteria as well as in animal or human cells and photomutagenic in Salmonella typhimurium strain TA102. This article tempts to explain the photochemistry and photomutagenicity mechanism. Light irradiation converts DMBA into several photoproducts including benz[a]anthracene-7,12-dione, 7-hydroxy-12-keto-7-methylbenz[a]anthracene, 7,12-epidioxy-7,12-dihydro-DMBA, 7-hydroxymethyl-12-methylbenz[a]anthracene and 12-hydroxymethyl-7-methylbenz[a]anthracene. Structures of these photoproducts have been identified by either comparison with authentic samples or by NMR/MS. At least four other photoproducts need to be assigned. Photo-irradiation of DMBA in the presence of calf thymus DNA was similarly conducted and light-induced DMBA-DNA adducts were analyzed by 32P-postlabeling/TLC, which indicates that multiple DNA adducts were formed. This indicates that formation of DNA adducts might be the source of photomutagenicity of DMBA. Metabolites obtained from the metabolism of DMBA by rat liver microsomes were reacted with calf thymus DNA and the resulting DNA adducts were analyzed by 32P-postlabeling/TLC under identical conditions. Comparison of the DNA adduct profiles indicates that the DNA adducts formed from photo-irradiation are different from the DNA adducts formed due to the reaction of DMBA metabolites with DNA. These results suggest that photo-irradiation of DMBA can lead to genotoxicity through activation pathways different from those by microsomal metabolism of DMBA.

  11. Polymorphism in Self-Assembled Structures of 9-Anthracene Carboxylic Acid on Ag(111

    Directory of Open Access Journals (Sweden)

    Bo Xu

    2012-06-01

    Full Text Available Surface self-assembly process of 9-anthracene carboxylic acid (AnCA on Ag(111 was investigated using STM. Depending on the molecular surface density, four spontaneously formed and one annealed AnCA ordered phases were observed, namely a straight belt phase, a zigzag double-belt phase, two simpler dimer phases, and a kagome phase. The two high-density belt phases possess large unit cells on the scale length of 10 nm, which are seldom observed in molecular self-assembled structures. This structural diversity stems from a complicated competition of different interactions of AnCA molecules on metal surface, including intermolecular and molecular-substrate interactions, as well as the steric demand from high molecular surface density.

  12. Investigating the anisotropic scintillation response in anthracene through neutron, gamma-ray, and muon measurements

    CERN Document Server

    Schuster, Patricia

    2015-01-01

    This paper reports a series of measurements that characterize the directional dependence of the scintillation response of crystalline anthracene to incident DT neutrons, DD neutrons, Cs-137 gamma rays, and, for the first time, cosmic ray muons. The neutron measurements give the amplitude and pulse shape dependence on the proton recoil direction over one hemisphere of the crystal, confirming and extending previous results in the literature. In similar measurements using incident gamma rays, no directional effect is evident, and any anisotropy with respect to the electron recoil direction is constrained to have a magnitude of less than a tenth of that present in the proton recoil events. Cosmic muons are measured at two directions, and no anisotropy is observed. This set of observations indicates that high dE/dx is necessary for an anisotropy to be present for a given type of scintillation event, which in turn could be used to discriminate among different hypotheses for the underlying causes of the anisotropy, ...

  13. Synthesis and characterization of Al- and Ti-MCM-41 materials: application to oxidation of anthracene

    Directory of Open Access Journals (Sweden)

    R. S. Araújo

    2007-03-01

    Full Text Available The synthesis and characterization of new molecular sieves of the MCM-41 type are presented in this study. Samples were obtained from the alkoxides of Si, Ti and Al and different long-chain amine and alkylammonium salts surfactants, by the sol-gel method, through moderate agitation at room temperature. The reactions were conducted in two steps, acid hydrolysis (pH=2 and alkaline condensation (pH=10, both taking about 90min. The synthesized crystals were characterized using infrared spectroscopy, thermogravimetry and X-Ray diffraction. Pore diameters and surface areas were measured by N2 adsorption at 77K. Catalytic tests were conducted for anthracene oxidation using different oxidants (H2O2, alkylhydroperoxide and organic solvents (benzene, tetrahydrofuran.

  14. Diazaquinomycins E–G, Novel Diaza-Anthracene Analogs from a Marine-Derived Streptomyces sp.

    Directory of Open Access Journals (Sweden)

    Michael W. Mullowney

    2014-06-01

    Full Text Available As part of our program to identify novel secondary metabolites that target drug-resistant ovarian cancers, a screening of our aquatic-derived actinomycete fraction library against a cisplatin-resistant ovarian cancer cell line (OVCAR5 led to the isolation of novel diaza-anthracene antibiotic diazaquinomycin E (DAQE; 1, the isomeric mixture of diazaquinomycin F (DAQF; 2 and diazaquinomycin G (DAQG; 3, and known analog diazaquinomycin A (DAQA; 4. The structures of DAQF and DAQG were solved through deconvolution of X-Ray diffraction data of their corresponding co-crystal. DAQE and DAQA exhibited moderate LC50 values against OVCAR5 of 9.0 and 8.8 μM, respectively. At lethal concentrations of DAQA, evidence of DNA damage was observed via induction of apoptosis through cleaved-PARP. Herein, we will discuss the isolation, structure elucidation, and biological activity of these secondary metabolites.

  15. A Dipolar Anthracene Dye: Synthesis, Optical Properties and Two-photon Tissue Imaging.

    Science.gov (United States)

    Moon, Hyunsoo; Jun, Yong Woong; Kim, Dokyoung; Ryu, Hye Gun; Wang, Taejun; Kim, Ki Hean; Huh, Youngbuhm; Jung, Junyang; Ahn, Kyo Han

    2016-09-20

    Two-photon microscopy is a powerful tool for studying biological systems. In search of novel two-photon absorbing dyes for bioimaging, we synthesized a new anthracene-based dipolar dye (anthradan) and evaluated its two-photon absorbing and imaging properties. The new anthradan, 9,10-bis(o-dimethoxy-phenyl)-anthradan, absorbs and emits at longer wavelengths than acedan, a well-known two-photon absorbing dye. It is also stable under two-photon excitation conditions and biocompatible, and thus used for two-photon imaging of mouse organ tissues to show bright, near-red fluorescence along with negligible autofluorescence. Such an anthradan thus holds promise as a new class of two-photon absorbing dyes for the development of fluorescent probes and tags for biological systems. PMID:27535006

  16. Intramolecular Charge-Transfer Interaction of Donor-Acceptor-Donor Arrays Based on Anthracene Bisimide.

    Science.gov (United States)

    Iwanaga, Tetsuo; Ogawa, Marina; Yamauchi, Tomokazu; Toyota, Shinji

    2016-05-20

    We designed anthracene bisimide (ABI) derivatives having two triphenylamine (TPA) groups as donor units at the 9,10-positions to form a novel π-conjugated donor-acceptor system. These compounds and their analogues with ethynylene linkers were synthesized by Suzuki-Miyaura and Sonogashira coupling reactions, respectively. In UV-vis spectra, the linker-free derivatives showed broad absorption bands arising from intramolecular charge-transfer interactions. Introducing ethynylene linkers resulted in a considerable red shift of the absorption bands. In fluorescence spectra, the ethynylene derivatives showed intense emission bands at 600-650 nm. Their photophysical and electrochemical properties were compared with those of the corresponding mono TPA derivatives on the basis of theoretical calculations and cyclic voltammetry to evaluate the intramolecular electronic interactions between the donor and acceptor units.

  17. IONIZATION AND FRAGMENTATION OF ANTHRACENE UPON INTERACTION WITH keV PROTONS AND α PARTICLES

    International Nuclear Information System (INIS)

    The interaction of keV ions with polyaromatic hydrocarbons is dominated by charge exchange and electronic stopping. We have studied the response of the polyaromatic hydrocarbon anthracene (C14H10) upon keV H+ and He2+ impact using high-resolution time-of-flight mass spectrometry. Extensive fragmentation into small CnH q+m as well as formation of up to triply charged parent ions is observed. Ab initio electron densities are used to calculate the molecular excitation due to electronic stopping. Fragment yields increase with the increase of electronic stopping as a function of projectile velocity. For equal electronic stopping, He2+ is found to induce more fragmentation than H+. The difference in fragmentation is concluded to be due to two electron processes, which are relevant channels only for He2+.

  18. A multielectrochromic copolymer based on anthracene and thiophene via electrochemical copolymerization in boron trifluoride diethyl etherate

    International Nuclear Information System (INIS)

    Highlights: ► A copolymer film based on anthracene and thiophene has been successfully deposited on ITO electrode in boron trifluoride diethyl etherate. ► The formation of the copolymer has been confirmed by CVs, FT-IR and XPS. ► The copolymer film presents multicolor electrochromism (yellowish red, yellow, yellow green, blue green, light blue and dark blue). ► The film has good electrochromic properties such as fast switching rate, reasonable coloration efficiency and stability. - Abstract: A copolymer based on thiophene and anthracene was prepared on indium tin oxide (ITO) glass electrode via electrochemical copolymerization in boron trifluoride diethyl etherate (BFEE). The resultant copolymer is characterized by cyclic voltammetry, FT-IR, XPS, SEM and spectroelectrochemical analysis. The copolymer film presents multicolor electrochromism and can exhibit six colors (yellowish red, yellow, yellow green, blue green, light blue and dark blue) under various applied potentials. The optical contrasts of the copolymer film at 491, 767 and 1100 nm are 21%, 38% and 37%, respectively, and the corresponding switching rates are 1.9, 1.3 and 2.3 s. The film has superior coloration efficiency which is calculated to be 327 cm2 C−1 (491 nm), 240 cm2 C−1 (767 nm) and 296 cm2 C−1 (1100 nm). Furthermore, the film presents reasonable electrochemical and optical stability which retains 73% of its original electroactivity after 500 cycles and 73.6% of its optical contrast after 800 steps. All of these indicate the satisfactory electrochromic properties of the copolymer film.

  19. Raman and surface enhanced Raman scattering study of the orientation of cruciform 9,10-anthracene thiophene and furan derivatives deposited on a gold colloidal surface

    Science.gov (United States)

    Muñoz-Pérez, J.; Leyton, P.; Paipa, C.; Soto, J. P.; Brunet, J.; Gómez-Jeria, J. S.; Campos-Vallette, M. M.

    2016-10-01

    The 9,10-di(thiophen-2-yl)anthracene (TAT), 9,10-di(furan-2-yl)anthracene (FAF) and 2-[(10-(thiophen-2-yl)anthracen-9-yl)]furan (TAF) cruciform molecular systems were synthesized using one-step coupling reactions and structurally characterized via Raman, infrared, 1H NMR, 13C NMR and mass spectroscopies. The orientation of the analytes on a gold colloidal surface was inferred from a surface-enhanced Raman scattering (SERS) study. The metal surface interaction was driven by the S and O atoms of the thiophene and furan α-substituents, and the plane of the anthracene fragment remained parallel to the surface. Theoretical calculations based on a simplified molecular model for the analyte-surface interaction provide a good representation of the experimental data.

  20. Fluorescence Quenching of Anthracene by N,N-Diethylaniline and Phenothiazine in Triton X-100/n-C10H21OH/H2O Microemulsion

    Institute of Scientific and Technical Information of China (English)

    GUO Xia; XU Hui; GUO Rong

    2003-01-01

    The photo-induced electron transfer reactions of anthracene with N,N-diethylaniline(DEA) and phenothiazine(PTZ) occur in the membrane phase of a Triton X-100/n-C10H21OH(1-decanol)/H2O microemulsion. DEA and PTZ exist in the membrane phase of the microemulsion. Anthracene exists in the oil continuous phase of the W/O microemulsion and in the oil core and membrane phase of the O/W microemulsion.

  1. Design of Poly(L-lactide)-Poly(ethylene glycol) Copolymer with Light-Induced Shape-Memory Effect Triggered by Pendant Anthracene Groups.

    Science.gov (United States)

    Xie, Hui; He, Man-jie; Deng, Xiao-Ying; Du, Lan; Fan, Cheng-Jie; Yang, Ke-Ke; Wang, Yu-Zhong

    2016-04-13

    A novel light-induced shape-memory material based on poly(l-lactide)-poly(ethylene glycol) copolymer is developed successfully by dangling the photoresponsive anthracene group on the PEG soft segment selectively. For synthesis strategy, the preprepared photoresponsive monomer N,N-bis(2-hydroxyethyl)-9-anthracene-methanamine (BHEAA) is first embedded into PEG chains; then, we couple this anthracene-functionalized PEG precursor with PLA precursor to result in PLA-PEG-A copolymer. The composition of target product can be well-defined by simply adjusting the feed ratio. The chemical structures of intermediate and final products are confirmed by (1)H NMR. Differential scanning calorimetry analysis of material reveals that the PEG soft segment became noncrystallizable when 4% or more BHEAA is introduced, and this feature is beneficial to the mobility of anthracene groups in polymer matrix. The static tensile tests show that the samples exhibit rubberlike mechanical properties except for the PLA-dominant one. The reversibility of [4 + 4] cycloaddition reaction between pendant anthracene groups in PLA-PEG-A film is demonstrated by UV-vis. Eventually, the light-induced shape-memory effect (LSME) is successfully realized in PLA-PEG-A. The results of cyclic photomechanical tests also reveal that the content of PLA hard segment as well as photosensitive anthracene moieties plays a crucial role in LSME.

  2. Anthraphane: An Anthracene-Based, Propeller-Shaped D(3h)-Symmetric Hydrocarbon Cyclophane and Its Layered Single Crystal Structures.

    Science.gov (United States)

    Servalli, Marco; Trapp, Nils; Wörle, Michael; Klärner, Frank-Gerrit

    2016-03-18

    The novel hydrocarbon propeller-shaped D3h-symmetric cyclophane (3), "anthraphane", was prepared through a revisited and optimized gram-scale synthesis of the key building block anthracene-1,8-ditriflate 7. Anthraphane has a high tendency to crystallize and single crystals in size ranges of 100-200 μm are easily obtained from different solvents. The crystallization behavior of 3 was extensively studied to unravel packing motifs and determine whether the packing can be steered into a desired direction, so to allow topochemical photopolymerization. SC-XRD shows that anthraphane packs in layers irrespective of the solvent used for crystallization. However, within the layers, intermolecular arrangements and π-π interactions of the anthracene units vary strongly. Four interaction motifs for the anthracene moieties are observed and discussed in detail: two types of exclusively edge-to-face (etf), a mixture of edge-to-face and face-to-face (ftf), and no anthracene-anthracene interaction at all. To elucidate why an exclusive ftf stacking was not observed, electrostatic potential surface (EPS) calculations with the semiempirical PM3 method were performed. They show qualitatively that the anthracene faces bear a strong negative surface potential, which may be the cause for this cyclophane to avoid ftf interactions. This combined crystallographic and computational study provides valuable insights on how to create all-ftf packings. PMID:26919259

  3. Anthracene and TCNQ doping of substituted nickel phthalocyanine: Effects on the electrical and optical properties of spin coated thin films

    Directory of Open Access Journals (Sweden)

    Hassan Aseel K.

    2013-08-01

    Full Text Available In this work, we study the controlled doping of thin films of substituted nickel phthalocyanine, NiPcR8, where R=-SC6H13, with anthracene and TCNQ and investigate the effects of the extent of this doping on the optical and electrical properties of NiPcR8 films. Optical constants, namely index of refraction (n and extinction coefficient (k have increased for both types of doping, as determined from spectroscopic ellipsometry measurements. Conductivity is shown to increase by about four orders of magnitudes compared to pure NiPcR8 films as a result of anthracene doping while TCNQ has resulted in almost six orders of magnitudes increase in the film’s conductivity.

  4. Pathway-Dependent Post-assembly Modification of an Anthracene-Edged M(II)4L6 Tetrahedron.

    Science.gov (United States)

    Ronson, Tanya K; Pilgrim, Ben S; Nitschke, Jonathan R

    2016-08-24

    Fe(II)4L6 tetrahedral cage 1 undergoes post-assembly modification (PAM) via a Diels-Alder cycloaddition of the anthracene panels of the cage with tetracyanoethylene (TCNE). The modified cage 2 possesses an enclosed cavity suitable for encapsulation of the fullerene C60, whereas original cage 1 forms a unique covalent adduct through a Diels-Alder cycloaddition of three of its anthracene ligands with C60. This adduct undergoes further PAM via reaction of the remaining three ligands with TCNE, enabling the isolation of two distinct products depending on the order of addition of C60 and TCNE. Modified cage 2 was also able to bind an anionic guest, [Co(C2B9H11)2](-), which was not encapsulated by the original cage, demonstrating the potential of PAM for tuning the binding properties of supramolecular hosts.

  5. Effect of Indole-3-Acetic Acid-Producing Bacteria on Phytoremediation of Soil Contaminated with Phenanthrene and Anthracene by Mungbean

    OpenAIRE

    Waraporn Chouychai; Thidarat Paemsom; Chittra Pobsuwan; Khanitta Somtrakoon; Hung Lee

    2016-01-01

    The use of indole-3-acetic acid (IAA)-producing bacteria isolated from non-contaminated weed rhizosphere to enhance plant growth and PAH phytoremediation capacity was investigated. IAA-producing bacterial isolates, designated NSRU1, NSRU2, and NSRU3, were isolated from the rhizosphere of Eleusine indica (Poaceae) and Chromolaena odorata (Asteraceae). The isolates were able to produce IAA in nutrient broth. However, when grown in the presence of 100 mg/l of either phenanthrene or anthracene, t...

  6. On the spin distribution in bridged anthracene-viologen molecules : an electron-nuclear double resonance study

    OpenAIRE

    Sariciftci, Serdar; Werner, Andreas; Grupp, Arthur; Mehring, Michael; Götz, Günther; Bäuerle, Peter; Effenberger, Franz

    1992-01-01

    Studies on the spin distribution in the radical state of anthracene-σ bridge viologen supermolecules with different bridge units are reported. Electronnuclear double resonance experiments (ENDOR) were performed on electrochemically reduced molecules. Proton hyperfine coupling constants at different molecular sites were obtained and are discussed in detail. The experimentally determined values are compared with quantum chemical calculations of the INDO type. The observed spin distribution...

  7. Effect of Indole-3-Acetic Acid-Producing Bacteria on Phytoremediation of Soil Contaminated with Phenanthrene and Anthracene by Mungbean

    Directory of Open Access Journals (Sweden)

    Waraporn Chouychai

    2016-07-01

    Full Text Available The use of indole-3-acetic acid (IAA-producing bacteria isolated from non-contaminated weed rhizosphere to enhance plant growth and PAH phytoremediation capacity was investigated. IAA-producing bacterial isolates, designated NSRU1, NSRU2, and NSRU3, were isolated from the rhizosphere of Eleusine indica (Poaceae and Chromolaena odorata (Asteraceae. The isolates were able to produce IAA in nutrient broth. However, when grown in the presence of 100 mg/l of either phenanthrene or anthracene, the amount of IAA produced by each isolate was reduced significantly. Mungbean seedlings were planted in 100 mg/kg phenanthrene- or anthracene-contaminated soil without or with inoculation of ≈106 CFU/g dry soil with one of the bacterial isolates. Inoculation with either NSRU1 or NSRU2 was effective at enhancing shoot length of mungbean in phenanthrene-contaminated soil on day 16. Also, inoculation with isolate NSRU1 led to increased root dry weight of mungbean in phenanthrene-contaminated soil on day 30. Phenanthrene and anthracene degradation on day 16 and 30 in planted and inoculated soil ranged between 92 - 93.8% and 92.2 - 94.1%, respectively, which were not significantly different from planted and uninoculated soil (93.9 and 94.9%. These data showed that IAA-producing bacteria could enhance plant growth, but was unable to increase PAH biodegradation under the conditions tested.

  8. Self-Assembly of Amphiphilic Anthracene-Functionalized β-Cyclodextrin (CD-AN) through Multi-Micelle Aggregation.

    Science.gov (United States)

    Zhang, Yuannan; Xu, Hongjie; Ma, Xiaodong; Shi, Zixing; Yin, Jie; Jiang, Xuesong

    2016-06-01

    Multi-micelle aggregation (MMA) mechanism is widely acknowledged to explicate large spherical micelles self-assembly, but the process of MMA during self-assembly is hard to observe. Herein, a novel kind of strong, regular microspheres fabricated from self-assembly of amphiphilic anthracene-functionalized β-cyclodextrin (CD-AN) via Cu(I)-catalyzed azide-alkyne click reactions is reported. The obtained CD-AN amphiphiles can self-assemble in water from primary core-shell micelles to secondary aggregates with the diameter changing from several tens nm to around 600-700 nm via MMA process according to the images of scanning electron microscopy, transmission electron microscopy, and atomic force microscopy as well as the dynamic light scattering measurements, followed by further crosslinking through photo-dimerization of anthracene. What merits special attention is that such photo-crosslinked self-assemblies are able to disaggregate reversibly into primary nanoparticles when changing the solution conditions, which is benefited from the designed regular structure of CD-AN and the rigid ranging of anthracene during assembly, thus confirming the process of MMA. PMID:27145434

  9. Vibrational properties of organic donor-acceptor molecular crystals: Anthracene-pyromellitic-dianhydride (PMDA) as a case study

    International Nuclear Information System (INIS)

    We establish a reliable quantum-mechanical approach to evaluate the vibrational properties of donor-acceptor molecular crystals. The anthracene-PMDA (PMDA = pyromellitic dianhydride) crystal, where anthracene acts as the electron donor and PMDA as the electron acceptor, is taken as a representative system for which experimental non-resonance Raman spectra are also reported. We first investigate the impact that the amount of nonlocal Hartree-Fock exchange (HFE) included in a hybrid density functional has on the geometry, normal vibrational modes, electronic coupling, and electron-vibrational (phonon) couplings. The comparison between experimental and theoretical Raman spectra indicates that the results based on the αPBE functional with 25%-35% HFE are in better agreement with the experimental results compared to those obtained with the pure PBE functional. Then, taking αPBE with 25% HFE, we assign the vibrational modes and examine their contributions to the relaxation energy related to the nonlocal electron-vibration interactions. The results show that the largest contribution (about 90%) is due to electron interactions with low-frequency vibrational modes. The relaxation energy in anthracene-PMDA is found to be about five times smaller than the electronic coupling

  10. Vibrational properties of organic donor-acceptor molecular crystals: Anthracene-pyromellitic-dianhydride (PMDA) as a case study

    KAUST Repository

    Fonari, A.

    2015-12-10

    We establish a reliable quantum-mechanical approach to evaluate the vibrational properties of donor-acceptor molecular crystals. The anthracene-PMDA (PMDA = pyromellitic dianhydride) crystal, where anthracene acts as the electron donor and PMDA as the electron acceptor, is taken as a representative system for which experimental non-resonance Raman spectra are also reported. We first investigate the impact that the amount of nonlocal Hartree-Fock exchange (HFE) included in a hybrid density functional has on the geometry, normal vibrational modes, electronic coupling, and electron-vibrational (phonon) couplings. The comparison between experimental and theoreticalRaman spectra indicates that the results based on the αPBE functional with 25%-35% HFE are in better agreement with the experimental results compared to those obtained with the pure PBE functional. Then, taking αPBE with 25% HFE, we assign the vibrational modes and examine their contributions to the relaxation energy related to the nonlocal electron-vibration interactions. The results show that the largest contribution (about 90%) is due to electron interactions with low-frequency vibrational modes. The relaxation energy in anthracene-PMDA is found to be about five times smaller than the electronic coupling.

  11. Vibrational properties of organic donor-acceptor molecular crystals: Anthracene-pyromellitic-dianhydride (PMDA) as a case study

    Energy Technology Data Exchange (ETDEWEB)

    Fonari, A.; Corbin, N. S.; Coropceanu, V., E-mail: jean-luc.bredas@kaust.edu.sa, E-mail: coropceanu@gatech.edu [School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332-0400 (United States); Vermeulen, D.; McNeil, L. E. [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3255 (United States); Goetz, K. P.; Jurchescu, O. D. [Department of Physics, Wake Forest University, Winston-Salem, North Carolina 27109-7507 (United States); Bredas, J. L., E-mail: jean-luc.bredas@kaust.edu.sa, E-mail: coropceanu@gatech.edu [School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332-0400 (United States); Solar and Photovoltaics Engineering Research Center, Division of Physical Science and Engineering, King Abdullah University of Science and Technology, Thuwal 23955-6900 (Saudi Arabia)

    2015-12-14

    We establish a reliable quantum-mechanical approach to evaluate the vibrational properties of donor-acceptor molecular crystals. The anthracene-PMDA (PMDA = pyromellitic dianhydride) crystal, where anthracene acts as the electron donor and PMDA as the electron acceptor, is taken as a representative system for which experimental non-resonance Raman spectra are also reported. We first investigate the impact that the amount of nonlocal Hartree-Fock exchange (HFE) included in a hybrid density functional has on the geometry, normal vibrational modes, electronic coupling, and electron-vibrational (phonon) couplings. The comparison between experimental and theoretical Raman spectra indicates that the results based on the αPBE functional with 25%-35% HFE are in better agreement with the experimental results compared to those obtained with the pure PBE functional. Then, taking αPBE with 25% HFE, we assign the vibrational modes and examine their contributions to the relaxation energy related to the nonlocal electron-vibration interactions. The results show that the largest contribution (about 90%) is due to electron interactions with low-frequency vibrational modes. The relaxation energy in anthracene-PMDA is found to be about five times smaller than the electronic coupling.

  12. Bioavailability and dissipation of anthracene from soil with different alkalinity and salinity.

    Science.gov (United States)

    Castro-Silva, Carolina; Ruiz-Valdiviezo, Víctor Manuel; Rivas-Rivera, Sandra Gabriela; Sosa-Trinidad, Alma Rosa; Luna-Guido, Marco; Delgado-Balbuena, Laura; Marsch, Rodolfo; Dendooven, Luc

    2015-01-01

    Bioavailability of contaminants, such as anthracene (Anthra), a polycyclic aromatic hydrocarbon (PAHs), and their removal from soil has been related to their extractability with non-exhaustive techniques, such as hydroxypropyl-beta-cyclodextrin (HPCD) or n-butanol. Anthra was extracted with HPCD, n-butanol and by exhaustive ultrasonic extraction method from sterilized and unsterilized alkaline soil of the former lake Texcoco, having pH ranging from pH 8.2 to 10.1 and electrolytic conductivity varying from 1.2 dS m(-1) to 95.2 dS m(-1), respectively. About 24.4 and 37.6% of Anthra was removed biologically from soil as estimated by exhaustive technique after 56 days. The percentage of Anthra that was removed from soil by exhaustive technique was not related to the amount thatwas extractable with HPCD or n-butanol. It was found that the Anthra extractable with n-butanol or HPCD did not correlate well with the removal of the contaminant from soil. In this study, the removal of Anthra from soil could not be predicted by the amount of Anthra that was extracted with n-butanol or HPCD .

  13. Discrimination of Primary Alkyl and Arylamines by a New Binaphthyl-Azacrown-Anthracene Fluorophore

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyu Jung; Li, Yinan; Kim, Kwang Soo; Hyun, Myung Ho [Pusan National Univ., Busan (Korea, Republic of)

    2010-04-15

    A new binaphthyl-azacrown-anthracene fluorophore (1) was prepared and utilized as a selective fluorescent chemosensor for the discrimination of primary alkyl and arylamine HCl salts in ethanol. Primary arylamine HCl salts were found to induce large CHEF effects with the excitation wavelength of 390 nm. On the other hand, primary alkylamine HCl salts were found not to induce any CHEF effect with the excitation wavelength of 390 nm. From the {sup 1}H NMR titration study, we found that primary arylamine HCl salts form complex effectively with compound 1 while primary alkylamine HCl salts do not. The development of highly sensitive and selective detection techniques for the discrimination of biologically toxic materials is of considerable importance in the fields of chemical, biological, and environmental sciences. Primary arylamines originated from occupational sources and/or tobacco smoking are known to be carcinogenic. For example, 4-aminobiphenyl, 2-naphthylamine and benzidine have been known to induce bladder cancer. In this instance, the methods for the detection of primary arylamines are quite important.

  14. Monte Carlo Study of the Fish-like Patterns of Anthracenes on Cu(111)

    Science.gov (United States)

    Kim, Kwangmoo; Einstein, T. L.; Sun, Dezheng; Kim, Dae-Ho; Bartels, Ludwig

    2011-03-01

    Using Monte Carlo calculations of the two-dimensional triangular lattice with a 2-component 3-state Potts model, we demonstrate a mechanism for the spontaneous formation of fish-like patterns of anthracene (AC) molecules on Cu(111) by sputtering and annealing, then cooling to ~ 80 K. The two components are an AC on a hollow site and another on a bridge site of Cu(111). The liquid crystal model with two separate parts, positional and orientational, only explains a part of the fish-like pattern, not the whole regular pattern. Our model fixes the positional order of AC's into the triangular lattice and the orientational order into three angles as observed in the experiments. The variation of the coverages of AC's is reflected in the change of the ratio of two components in our model. We also try to understand the compression of AC's with the introduction of Gaussian dispersion of AC's about their triangular lattice sites. Supported primarily by NSF Grants CHE 07-50334 with a secondary support from NSF-MRSEC at the University of Maryland, DMR05-20471. Work at UCR supported primarily by NSF CHE 07-49949.

  15. Optical Properties of Oligo(fluorene-vinylene) Functionalized Anthracene Linear Oligomers: Effect of π-extension

    Institute of Scientific and Technical Information of China (English)

    Tian-hao Huang; Li-li Qu; Zhi-hui Kang; Ying-hui Wang; Ran Lu; Er-long Miao; Fei Wang

    2013-01-01

    The photo-physical properties of oligo(fluorene-vinylene) functionalized anthracene linear oligomers (An-OFVn (n=1-4)) have been systemically investigated through experimental and theoretical methods.The steady-state spectral measurement shows that the increasing of fluorene-vinylene (FV) group could lead to the red shift of absorption spectra and restrain the excimer formation between oligomers.Quantum chemical calculations exhibit that the energy levels of HOMO,LUMO,and the band gap gradually converge to a constant in accompany with the increasing of FV unit.Meanwhile,the electronic cloud which distributes on the branch arms,also gradually enhances and makes the absorption spectral shape of oligomers become similar to that of branch arms step by step.The time-resolved fluorescence tests exhibits that the lifetime of excimer emission would be ahmost invariable after the number of FV group in oligomer is >2.In nonlinear optical test,the two-photon photoluminescence efficiency and two-photon absorption cross-section will both gradually enhance and be close to an extrenum after the number of FV unit is equal to 4.These results will provide a guideline for the design of novel photo-electronic materials.

  16. Biodegradation of anthracene and fluoranthene by fungi isolated from an experimental constructed wetland for wastewater treatment.

    Science.gov (United States)

    Giraud, F; Guiraud, P; Kadri, M; Blake, G; Steiman, R

    2001-12-01

    Pilot-scale constructed wetlands were used to treat water contaminated by polycyclic aromatic hydrocarbons (PAHs), particularly fluoranthene, and the possible role of fungi present in these ecosystems was investigated. A total of 40 fungal species (24 genera) were isolated and identified from samples (gravel and sediments) from a contaminated wetland and a control wetland. All of them were assayed for their ability to remove anthracene (AC) and fluoranthene (FA) from liquid medium. FA was degraded efficiently by 33 species while only 2 species were able to remove AC over 70%. A selection of 10 strains of micromycetes belonging to various taxonomic groups was further investigated for FA and AC degradation, toxicity assays and phenoloxidases (POx) detection. Interesting and not previously reported species were revealed (Absidia cylindrospora, Cladosporium sphaerospermum, and Ulocladium chartarum). They were all able to highly degrade the PAH-model compounds chosen. An interesting inducibility was noted for Ulocladium chartarum. Degradative ability of fungi was not related to their extracellular POx activity. This study may contribute to the improvement of constructed wetlands for water treatment, which may be enriched in efficient fungi. PMID:11791842

  17. Crystal induced phosphorescence from Benz(a)anthracene microcrystals at room temperature.

    Science.gov (United States)

    Maity, Samir; Mazumdar, Prativa; Shyamal, Milan; Sahoo, Gobinda Prasad; Misra, Ajay

    2016-03-15

    Pure organic compounds that are also phosphorescent at room temperature are very rare in literature. Here, we report efficient phosphorescence emission from aggregated hydrosol of Benz(a)anthracene (BaA) at room temperature. Aggregated hydrosol of BaA has been synthesized by re-precipitation method and SDS is used as morphology directing agent. Morphology of the particles is characterized using optical and scanning electronic microcopy (SEM). Photophysical properties of the aggregated hydrosol are carried out using UV-vis, steady state and time resolved fluorescence study. The large stoke shifted structured emission from aggregated hydrosol of BaA has been explained due to phosphorescence emission of BaA at room temperature. In the crystalline state, the restricted intermolecular motions (RIM) such as rotations and vibrations are activated by crystal lattice. This rigidification effect makes the chromophore phosphorescent at room temperature. The possible stacking arrangement of the neighboring BaA within the aggregates has been substantiated by computing second order Fukui parameter as local reactivity descriptors. Computational study also reveals that the neighboring BaA molecules are present in parallel slipped conformation in its aggregated crystalline form. PMID:26720419

  18. The anharmonic quartic force field infrared spectra of three polycyclic aromatic hydrocarbons: Naphthalene, anthracene, and tetracene

    Energy Technology Data Exchange (ETDEWEB)

    Mackie, Cameron J., E-mail: mackie@strw.leidenuniv.nl; Candian, Alessandra; Tielens, Alexander G. G. M. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Huang, Xinchuan [SETI Institute, 189 Bernardo Avenue, Suite 100, Mountain View, California 94043 (United States); Maltseva, Elena; Buma, Wybren Jan [University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Petrignani, Annemieke [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Radboud University, FELIX Laboratory, Toernooiveld 7, 6525 ED Nijmegen (Netherlands); Oomens, Jos [Radboud University, FELIX Laboratory, Toernooiveld 7, 6525 ED Nijmegen (Netherlands); Lee, Timothy J. [NASA Ames Research Center, Moffett Field, California 94035-1000 (United States)

    2015-12-14

    Current efforts to characterize and study interstellar polycyclic aromatic hydrocarbons (PAHs) rely heavily on theoretically predicted infrared (IR) spectra. Generally, such studies use the scaled harmonic frequencies for band positions and double harmonic approximation for intensities of species, and then compare these calculated spectra with experimental spectra obtained under matrix isolation conditions. High-resolution gas-phase experimental spectroscopic studies have recently revealed that the double harmonic approximation is not sufficient for reliable spectra prediction. In this paper, we present the anharmonic theoretical spectra of three PAHs: naphthalene, anthracene, and tetracene, computed with a locally modified version of the SPECTRO program using Cartesian derivatives transformed from Gaussian 09 normal coordinate force constants. Proper treatments of Fermi resonances lead to an impressive improvement on the agreement between the observed and theoretical spectra, especially in the C–H stretching region. All major IR absorption features in the full-scale matrix-isolated spectra, the high-temperature gas-phase spectra, and the most recent high-resolution gas-phase spectra obtained under supersonically cooled molecular beam conditions in the CH-stretching region are assigned.

  19. Toxicity of 14 photooxidized anthracene derivatives to Lemna gibba L.G-3

    Energy Technology Data Exchange (ETDEWEB)

    Mallakin, A.; MacConkey, B.J.; McKibbenyen, B.; Sniekusyen, V.; Dixon, D.G.; Greenberg, B.M. [Univ. of Waterloo, Ontario (Canada)

    1995-12-31

    Phototoxicity of PAHs is known to occur via photosensitization reactions and potentially by photomodification of chemicals to more toxic species. The hazards enhancement of polycyclic aromatic hydrocarbon (PAHs) toxicity to plants by artificial light source and natural solar radiation has been recently demonstrated. Growth and chlorosis were used as end points to assess the photoinduced toxicity to 14 oxygenated anthracene derivatives to Lemna gibba. Reversed-phase liquid chromatography (HPLC) equipped with diode array detector was used as analytical technique for measurement of polycyclic aromatic hydrocarbons photomodification products and to study the modification kinetics. The toxicity bioassays were performed both under visible light and simulated solar radiation (SSR), which mimicked the relative load of UV + visible light in solar radiation. Comparative studies with visible and SSR showed that the phototoxicity of these chemicals was activated, with UV radiation being the most influenced spectral region in enhancing the harmful effects of the chemicals. Photomodified PAHs exhibited toxicity in visible light and increased toxicity in simulate solar radiation. The rates of photomodification of chemicals were quite different but rapid enough to contribute to toxicity. There was increase in inhibition of growth of plants, relative to control, with increasing in rate of photomodification of the oxygenated PAHs.

  20. Diindeno-fusion of an anthracene as a design strategy for stable organic biradicals

    Science.gov (United States)

    Rudebusch, Gabriel E.; Zafra, José L.; Jorner, Kjell; Fukuda, Kotaro; Marshall, Jonathan L.; Arrechea-Marcos, Iratxe; Espejo, Guzmán L.; Ponce Ortiz, Rocío; Gómez-García, Carlos J.; Zakharov, Lev N.; Nakano, Masayoshi; Ottosson, Henrik; Casado, Juan; Haley, Michael M.

    2016-08-01

    The consequence of unpaired electrons in organic molecules has fascinated and confounded chemists for over a century. The study of open-shell molecules has been rekindled in recent years as new synthetic methods, improved spectroscopic techniques and powerful computational tools have been brought to bear on this field. Nonetheless, it is the intrinsic instability of the biradical species that limits the practicality of this research. Here we report the synthesis and characterization of a molecule based on the diindeno[b,i]anthracene framework that exhibits pronounced open-shell character yet possesses remarkable stability. The synthetic route is rapid, efficient and possible on the gram scale. The molecular structure was confirmed through single-crystal X-ray diffraction. From variable-temperature Raman spectroscopy and magnetic susceptibility measurements a thermally accessible triplet excited state was found. Organic field-effect transistor device data show an ambipolar performance with balanced electron and hole mobilities. Our results demonstrate the rational design and synthesis of an air- and temperature-stable biradical compound.

  1. Facile and economical synthesis of high-contrast multielectrochromic copolymers based on anthracene and 3,4-ethylenedioxythiophene via electrocopolymerization in boron trifluoride diethyl etherate

    International Nuclear Information System (INIS)

    Highlights: ► We prepared copolymers based on anthracene and EDOT in BFEE solution. ► The copolymer film exhibits multicolor electrochromism and tunable color change with the feed ratio. ► The copolymer prepared with the feed ratio of anthracene/EDOT at 1/4 has a maximum optical contrast of 82% at 503 nm. ► The copolymer film presents reasonable switching response, good color retaining ability and electrochemical stability. - Abstract: Copolymers based on anthracene and 3,4-ethylenedioxythiophene (EDOT) are successfully electrodeposited on ITO electrodes in boron trifluoride diethyl etherate (BFEE). The resultant copolymers are characterized by cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and spectroelectrochemical analysis. The copolymer films can present multicolor electrochromism under various applied potentials and the color change can be tuned through controlling the feed ratio of anthracene/EDOT. With the feed ratio of anthracene/EDOT at 1/4, the prepared copolymer shows a maximum optical contrast of 82% at 503 nm which is much near to the highest optical contrast of electrochromic materials. The switching time and coloration efficiency at 507 nm are 2.3 s and 278 cm C−1, respectively. Furthermore, the copolymer exhibits excellent electrochemical stability which retains 89.8% of its original electroactivity after 2000 cycles.

  2. Organic light-emitting diodes based on 9-(2-naphthyl)anthracene derivatives with a triphenylsilane unit as the deep-blue emitting layer

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ji Young; Lee, Seul Bee [Department of Chemistry, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Lee, Seok Jae [Department of Information Display, Hongik University, Seoul 121-791 (Korea, Republic of); Kim, Young Kwan, E-mail: kimyk@wow.hongik.ac.kr [Department of Information Display, Hongik University, Seoul 121-791 (Korea, Republic of); Yoon, Seung Soo, E-mail: ssyoon@skku.edu [Department of Chemistry, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2015-02-27

    A series of 9-(2-naphthyl)anthracene derivatives with a triphenylsilane unit, which prevented molecular aggregation and self-quenching effect, was designed and synthesized. By using various bridges between the 9-(2-naphthyl)anthracene group and the triphenylsilane unit, five deep-blue emitters were obtained and applied as non-doped emitting materials in organic light-emitting diodes (OLEDs) with a device structure of indium–tin-oxide (ITO) (180 nm)/4,4-bis(N-(1-naphthyl)-N-phenylamino)biphenyl (NPB) (50 nm)/emitting materials (30 nm)/4,7-diphenyl-1,10-phenanthroline (Bphen) (30 nm)/lithium quinolate (Liq) (2 nm)/Aluminium (100 nm). All devices showed blue emissions and their electroluminescence efficiencies are sensitive to the structural changes of the emitting materials. In particular, a device using 9-(2-naphthalenyl)-10-[6-(triphenylsilyl)-2-naphthalenyl]-anthracene (4) exhibited high luminous, power and quantum efficiencies of 2.28 cd/A, 1.42 lm/W and 2.40% at 20 mA/cm{sup 2}, respectively, and this device showed the deep blue emission with the CIE coordinates of (0.16, 0.10) at 6.0 V. - Highlights: • We synthesized 9-(2-naphthyl)anthracene derivatives with a triphenylsilane unit. • We study the conjugation-length effect on the electroluminescence properties. • The bulky triphenylsilane-anthracene derivatives show resistance to self-aggregation.

  3. Synthesis, characterization and properties of yellow-light-emitting polyethers containing bis(styryl)anthracene units

    Energy Technology Data Exchange (ETDEWEB)

    Gioti, M., E-mail: mgiot@physics.auth.gr; Pitsalidis, C., E-mail: mgiot@physics.auth.gr; Tzounis, L.; Logothetidis, S., E-mail: logot@auth.gr [Laboratory for Thin Films-Nanosystems and Nanometrology (LTFN), Physics Department, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece); Andreopoulou, A. K.; Kallitsis, J. K. [Department of Chemistry, University of Patras, University Campus, Rio-Patras GR26504, Greece and Foundation for Research and Technology Hellas, Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Platani Str., Patras GR26504 (Greece); Mparmpoutsis, E. [Department of Chemistry, University of Patras, University Campus, Rio-Patras GR26504 (Greece)

    2015-02-17

    Aromatic aliphatic polyethers containing bis(styryl)anthracene units in the main chain separated by flexible spacer of 11 (AND52) or 12 (AND53) methylene units, were synthesized and characterized aiming to be applied as emitting materials in polymer light emitting diode (PLED) devices. The polymers are soluble in common organic solvents and have average molecular weight of about 15kDa. Differentiations owing to an odd-even number of methylene units (χ=11 vs χ=12) are observed in their optical properties in solid state. Thin films as well as PLED devices were fabricated via conventional spin-coating process. Initially, various parameters have been investigated concerning the solubility of the polymers, the effect of film thickness on the electrical properties, and their thermal stability. The optical properties of the two polymers were investigated by NIR-Vis-far UV spectroscopic ellipsometry (SE). The accurate determination of the thickness and the optical constants (refractive index and dielectric function as a function of wavelength) were derived. These provide substantial insights into the final design of the optimum final multi-layer structure of the PLEDs, if we take into account that the external quantum efficiency (EQE) of electroluminescence (EL) strongly depends on the optical interference of the beams of emitted light that have been multiply reflected from the layer interfaces. The morphological characterization of the AND52 and AND53 polymeric thin films was carried out using atomic force microscopy (AFM), while current density-voltage (J-V) characteristics of the devices were studied by electrical measurements. The single PLED devices were switched on at relatively low operation voltages, showing the potential as backplanes for active matrix PLED applications. In this perspective, it can be assumed that further studies of the presented materials will enable the development of flexible PLEDs with the possibility to scale up their dimensions for bigger

  4. A search for interstellar anthracene towards the Perseus anomalous microwave emission region

    Science.gov (United States)

    Iglesias-Groth, S.; Manchado, A.; Rebolo, R.; González Hernández, J. I.; García-Hernández, D. A.; Lambert, D. L.

    2010-10-01

    We report the discovery of a new broad interstellar (or circumstellar) band at 7088.8 +/- 2.0 Å coincident to within the measurement uncertainties with the strongest band of the anthracene cation (C14H10+) as measured in gas-phase laboratory spectroscopy at low temperatures. The band is detected in the line of sight of star Cernis 52, a likely member of the very young star cluster IC 348, and is probably associated with cold absorbing material in an intervening molecular cloud of the Perseus star-forming region where various experiments have recently detected anomalous microwave emission. From the measured intensity and available oscillator strength we find a column density of implying that ~0.008 per cent of the carbon in the cloud could be in the form of C14H10+. A similar abundance has been recently claimed for the naphthalene cation in this cloud. This is the first location outside the Solar system where specific polycyclic aromatic hydrocarbons (PAHs) are identified. We report observations of interstellar lines of CH and CH+ that support a rather high column density for these species and for molecular hydrogen. The strength ratio of the two prominent diffuse interstellar bands at 5780 and 5797 Å suggests the presence of a `zeta'-type cloud in the line of sight (consistent with steep far-ultraviolet extinction and high molecular content). The presence of PAH cations and other related hydrogenated carbon molecules which are likely to occur in this type of clouds reinforces the suggestion that electric dipole radiation from fast-spinning PAHs is responsible of the anomalous microwave emission detected towards Perseus.

  5. Anthracene appended pyridinium amide–urea conjugate in selective fluorometric sensing of L-N-acetylvaline salt

    OpenAIRE

    Kumaresh Ghosh; Tanmay Sarkar; Chattopadhyay, Asoke P

    2010-01-01

    A new anthracene labeled pyridinium amide–urea conjugate 1 has been designed and synthesized. The receptor shows a different fluorometric response with L-N-acetylvaline and L-N-acetylalanine salts in CH3CN in contrast to the other salts of L-N-acetyl α-amino acids and (S)-α-hydroxy acids studied. Upon complexation of the tetrabutylammonium salt of L-N-acetylvaline, the emission of 1 increases accompanied by the formation of a new band at higher wavelength and this characterist...

  6. Anthracene appended pyridinium amide–urea conjugate in selective fluorometric sensing of L-N-acetylvaline salt

    OpenAIRE

    Ghosh, Kumaresh; Sarkar, Tanmay; Chattopadhyay, Asoke P

    2010-01-01

    A new anthracene labeled pyridinium amide–urea conjugate 1 has been designed and synthesized. The receptor shows a different fluorometric response with L-N-acetylvaline and L-N-acetylalanine salts in CH3CN in contrast to the other salts of L-N-acetyl α-amino acids and (S)-α-hydroxy acids studied. Upon complexation of the tetrabutylammonium salt of L-N-acetylvaline, the emission of 1 increases accompanied by the formation of a new band at higher wavelength and this characteristic change distin...

  7. Toxicity of benz(a)anthracene and fluoranthene to marine phytoplankton in culture: Does cell size really matter?

    Energy Technology Data Exchange (ETDEWEB)

    Othman, Hiba Ben [UMR 5119 ECOSYM, CNRS-IRD-Universite Montpellier II-Ifremer-Universite Montpellier I, SMEL 2 rue des Chantiers, F-34200 Sete (France); Laboratoire de Cytologie Vegetale et Phytoplanctonologie, Faculte des Sciences de Bizerte, Universite de Carthage, Zarzouna 7021, Bizerte (Tunisia); Leboulanger, Christophe, E-mail: christophe.leboulanger@ird.fr [UMR 5119 ECOSYM, CNRS-IRD-Universite Montpellier II-Ifremer-Universite Montpellier I, SMEL 2 rue des Chantiers, F-34200 Sete (France); Le Floc' h, Emilie [UMS MEDIMEER, CNRS-Universite Montpellier II, SMEL 2 rue des Chantiers F-34200 Sete (France); Hadj Mabrouk, Hassine; Sakka Hlaili, Asma [Laboratoire de Cytologie Vegetale et Phytoplanctonologie, Faculte des Sciences de Bizerte, Universite de Carthage, Zarzouna 7021, Bizerte (Tunisia)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Polycyclic aromatic hydrocarbons (PAHs) in the marine environment are a hazardous chemical legacy. Black-Right-Pointing-Pointer Benz(a)anthracene and fluoranthene are toxic to phytoplankton photosynthesis and growth in culture. Black-Right-Pointing-Pointer Acute (photosynthesis) and chronic (population growth) effects have different thresholds. Black-Right-Pointing-Pointer Toxicity depends on both the species selected as a model and the compound considered. Black-Right-Pointing-Pointer Further study of the size/sensitivity relationship is required to draw more general conclusions. - Abstract: The toxicity of benz(a)anthracene and fluoranthene (polycyclic aromatic hydrocarbons, PAHs) was evaluated on seven species of marine algae in culture belonging to pico-, nano-, and microphytoplankton, exposed to increasing concentrations of up to 2 mg L{sup -1}. The short-term (24 h) toxicity was assessed using chlorophyll a fluorescence transients, linked to photosynthetic parameters. The maximum quantum yield Fv/Fm was lower at the highest concentrations tested and the toxicity thresholds were species-dependent. For acute effects, fluoranthene was more toxic than benz(a)anthracene, with LOECs of 50.6 and 186 {mu}g L{sup -1}, respectively. After 72 h exposure, there was a dose-dependent decrease in cell density, fluoranthene being more toxic than benz(a)anthracene. The population endpoint at 72 h was affected to a greater extent than the photosynthetic endpoint at 24 h. EC50 was evaluated using the Hill model, and species sensitivity was negatively correlated to cell biovolume. The largest species tested, the dinoflagellate Alexandrium catenella, was almost insensitive to either PAH. The population endpoint EC50s for fluoranthene varied from 54 {mu}g L{sup -1} for the picophytoplankton Picochlorum sp. to 418 {mu}g L{sup -1} for the larger diatom Chaetoceros muelleri. The size/sensitivity relationship is proposed as a useful model when

  8. Stereoselective metabolism of dibenz(a,h)anthracene to trans-dihydrodiols and their activation to bacterial mutagens.

    OpenAIRE

    Platt, K L; Schollmeier, M.; Frank, H; Oesch, F

    1990-01-01

    Dibenz(a,h)anthracene (DBA), a carcinogenic, polycyclic aromatic hydrocarbon ubiquitous in the environment, is metabolized by the hepatic microsomal fraction of immature Sprague-Dawley rats pretreated with Aroclor 1254 to 27 ethyl acetate-extractable metabolites. More than half of these metabolites (51%) consisted of trans-1,2-; -3,4-; and -5,6-dihydrodiols including their identified secondary metabolites. The three trans-dihydrodiols (4.9, 15.8, and 0.6% of total metabolic conversion) were h...

  9. Mono- and Dinuclear Manganese Carbonyls Supported by 1,8-Disubstituted (L = Py, SMe, SH) Anthracene Ligand Scaffolds.

    Science.gov (United States)

    Manes, Taylor A; Rose, Michael J

    2016-06-01

    Presented herein is a synthetic scheme to generate symmetric and asymmetric ligands based on a 1,8-disubstituted anthracene scaffold. The metal-binding scaffolds were prepared by aryl chloride activation of 1,8-dichloroanthracene using Suzuki-type couplings facilitated by [Pd(dba)2] as a Pd source; the choice of cocatalyst (XPhos or SPhos) yielded symmetrically or asymmetrically substituted scaffolds (respectively): namely, Anth-SMe2 (3), Anth-N2 (4), and Anth-NSMe (6). The ligands exhibit a nonplanar geometry in the solid state (X-ray), owing to steric hindrance between the anthracene scaffold and the coupled aryl units. To determine the flexibility and binding characteristics of the anthracene-based ligands, the symmetric scaffolds were complexed with [Mn(CO)5Br] to afford the mononuclear species [(Anth-SMe2)Mn(CO)3Br] (8) and [(Anth-N2)Mn(CO)3Br] (9), in which the donor moieties chelate the Mn center in a cis fashion. The asymmetric ligand Anth-NSMe (6) binds preferentially through the py moieties, affording the bis-ligated complex [(Anth-NSMe)2Mn(CO)3Br] (10), wherein the thioether-S donors remain unbound. Alternatively, deprotection of the thioether in 6 affords the free thiol ligand Anth-NSH (7), which more readily binds the Mn center. Complexation of 7 ultimately affords the mixed-valence Mn(I)/Mn(II) dimer of formula [(Anth-NS)3Mn2(CO)3] (11), which exhibits a fac-{Mn(CO)3} unit supported by a triad of bridging thiolates, which are in turn ligated to a supporting Mn(II) center (EPR: |D| = 0.053 cm(-1), E/|D| = 0.3, Aiso = -150 MHz). All of the metal complexes have been characterized by single-crystal X-ray diffraction, IR spectroscopy and NMR/EPR measurements-all of which demonstrate that the meta-linked, anthracene-based ligand scaffold is a viable approach for the coordination of metal carbonyls. PMID:27195661

  10. Chemical insight from density functional modeling of molecular adsorption: Tracking the bonding and diffusion of anthracene derivatives on Cu(111) with molecular orbitals

    Science.gov (United States)

    Wyrick, Jonathan; Einstein, T. L.; Bartels, Ludwig

    2015-03-01

    We present a method of analyzing the results of density functional modeling of molecular adsorption in terms of an analogue of molecular orbitals. This approach permits intuitive chemical insight into the adsorption process. Applied to a set of anthracene derivates (anthracene, 9,10-anthraquinone, 9,10-dithioanthracene, and 9,10-diselenonanthracene), we follow the electronic states of the molecules that are involved in the bonding process and correlate them to both the molecular adsorption geometry and the species' diffusive behavior. We additionally provide computational code to easily repeat this analysis on any system.

  11. Effects of humic acids and microorganisms on decabromodiphenyl ether, 4,4′-dibromodiphenyl ether and anthracene transportation in soil

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this study, effects of humic acids (HA) and microorganisms on the migration of hydrophobic organic contaminants (HOCs), decabromodiphenyl ether (BDE-209), 4,4′-dibromodiphenyl ether (BDE-15) and anthracene, in soils were examined. More soil particles were dispersed into the colloidal phase (0.22-1 μm) in the presence of HA and/or microorganisms as a result of increased erosion and friction. The study suggested that PBDEs (BDE-209 and BDE-15) and anthracene in soils would be transported to other places by soil colloids with surface and underground water flow given the high concentrations of HA and microorganisms in the natural environment.

  12. Chemical insight from density functional modeling of molecular adsorption: Tracking the bonding and diffusion of anthracene derivatives on Cu(111) with molecular orbitals

    Energy Technology Data Exchange (ETDEWEB)

    Wyrick, Jonathan; Bartels, Ludwig, E-mail: ludwig.bartels@ucr.edu [Pierce Hall, University of California-Riverside, Riverside, California 92521 (United States); Einstein, T. L. [Department of Physics and Condensed Matter Theory Center, University of Maryland, College Park, Maryland 20742-4111 (United States)

    2015-03-14

    We present a method of analyzing the results of density functional modeling of molecular adsorption in terms of an analogue of molecular orbitals. This approach permits intuitive chemical insight into the adsorption process. Applied to a set of anthracene derivates (anthracene, 9,10-anthraquinone, 9,10-dithioanthracene, and 9,10-diselenonanthracene), we follow the electronic states of the molecules that are involved in the bonding process and correlate them to both the molecular adsorption geometry and the species’ diffusive behavior. We additionally provide computational code to easily repeat this analysis on any system.

  13. Effects of anthracene on filtration rates, antioxidant defense system, and redox proteomics in the Mediterranean clam Ruditapes decussatus (Mollusca: Bivalvia).

    Science.gov (United States)

    Sellami, Badreddine; Khazri, Abdelhafidh; Louati, Héla; Dellali, Mohamed; Driss, Mouhamed Ridha; Aïssa, Patricia; Mahmoudi, Ezzeddine; Hamouda, Beyrem; Coelho, Ana Varela; Sheehan, David

    2015-07-01

    This study aimed at analyzing the impact of a toxic polyaromatic hydrocarbon (PAH), anthracene (ANT), on Ruditapes decussatus collected from a Tunisian coastal lagoon (Bizerte Lagoon). Filtration rates, several antioxidant enzymes--superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione transferase (GST)--as well as indices of protein oxidation status were determined in various tissues of this bivalve. Specimens were exposed to 100 μg/L of ANT for 2 days. ANT levels were evaluated using HPLC and were detected in the gill and digestive gland at different amounts. ANT exposure altered the behavior of bivalves by changing the siphon movement and decreasing filtration rate significantly. The enzymatic results indicated that ANT exposure affected the oxidative stress status of the gills of R. decussatus. In addition, modification of proteins was detected in the gills using redox proteomics after ANT treatment. Three protein spots were successfully identified by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry (MALDI-TOF-MS). These proteins can be roughly related to muscle contraction function. In contrast, no significant modification of enzymatic and protein responses was detected in the digestive gland after ANT treatment. These data demonstrate that combined behavioral and biochemical analyses are a powerful tool to provide valuable insights into possible mechanisms of toxicity of anthracene in R. decussatus. Additionally, the results highlight the potential of the gill as a valuable candidate for investigating PAH toxicity. PMID:25779113

  14. Sterilization affects soil organic matter chemistry and bioaccumulation of spiked p,p'-DDE and anthracene by earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Kelsey, Jason W., E-mail: kelsey@muhlenberg.ed [Program in Environmental Science and Department of Chemistry, Muhlenberg College, 2400 Chew Street, Allentown, PA 18104 (United States); Slizovskiy, Ilya B.; Peters, Richard D.; Melnick, Adam M. [Program in Environmental Science and Department of Chemistry, Muhlenberg College, 2400 Chew Street, Allentown, PA 18104 (United States)

    2010-06-15

    Laboratory experiments were conducted to assess the effects of soil sterilization on the bioavailability of spiked p,p'-DDE and anthracene to the earthworms Eisenia fetida and Lumbricus terrestris. Physical and chemical changes to soil organic matter (SOM) induced by sterilization were also studied. Uptake of both compounds added after soil was autoclaved or gamma irradiated increased for E. fetida. Sterilization had no effect on bioaccumulation of p,p'-DDE by L. terrestris, and anthracene uptake increased only in gamma-irradiated soils. Analyses by FT-IR and DSC indicate sterilization alters SOM chemistry and may reduce pollutant sorption. Chemical changes to SOM were tentatively linked to changes in bioaccumulation, although the effects were compound and species specific. Artifacts produced by sterilization could lead to inaccurate risk assessments of contaminated sites if assumptions derived from studies carried out in sterilized soil are used. Ultimately, knowledge of SOM chemistry could aid predictions of bioaccumulation of organic pollutants. - Soil sterilization affects soil organic matter chemistry and pollutant bioaccumulation.

  15. Excellent deep-blue emitting materials based on anthracene derivatives for non-doped organic light-emitting diodes

    Science.gov (United States)

    Wang, Zhiqiang; Liu, Wei; Xu, Chen; Ji, Baoming; Zheng, Caijun; Zhang, Xiaohong

    2016-08-01

    Two deep-blue emitting materials 2-tert-butyl-9,10-bis(3,5-diphenylphenyl)anthracene (An-1) and 2-tert-butyl-9,10-bis(3,5-diphenylbiphenyl-4‧-yl)anthracene (An-2) were successfully synthesized by the Pd-catalyzed Suzuki coupling reaction. Both of these compounds have high thermal stabilities and show strong deep-blue emission as solid-state film as well as in n-hexane solution. Two non-doped electroluminescent devices employing An-1 and An-2 as emitting layers were fabricated by vacuum vapor deposition. These devices exhibited highly efficient and stable deep-blue emission with high color purity. The CIE coordinate and maximum EQE of An-1 based device are 4.2% and (0.16, 0.06), respectively. Device based on An-2 achieved a maximum EQE of 4.0% and a CIE coordinate of (0.16, 0.10).

  16. Mass spectrometric analysis of 7-sulfoxymethyl-12-methylbenz[a]anthracene and related electrophilic polycyclic aromatic hydrocarbon metabolites.

    Science.gov (United States)

    Lehner, Andreas F; Horn, Jamie; Flesher, James W

    2004-11-01

    The Meso-region theory of polycyclic aromatic hydrocarbon (PAH) carcinogenesis predicts that the development of pronounced carcinogenicity depends on the introduction of a good leaving group on alkyl side-chains attached to the exceptionally reactive meso-anthracenic or L-region positions of PAHs. Thus, the first step in carcinogenesis by methylated PAHs such as 7,12-dimethylbenz[a]anthracene (DMBA) would be the hydroxylation of the L-region methyl groups, particularly the 7-methyl group. The second would be the formation of a metabolite, e.g. a sulfate ester, which is expected to be a good leaving group capable of generating a highly reactive benzylic carbocation. 7-Hydroxymethyl-12-methylbenz[a]anthracene (7-HMBA) is a metabolite of DMBA, and sulfation of 7-HMBA to a 7-sulfoxymethyl metabolite (7-SMBA) is a known Phase II metabolic process designed to facilitate excretion, but actually enabling more destructive side-reactions. These side-reactions occur with generation of an electrophilic 7-methylene carbonium ion, and/or by in vivo halide exchange to provide neutral side-products more capable of entering cells, especially those of DMBA target tissues. Electrospray ionization mass spectrometry (MS) enabled us to visualize 7-SMBA as an intact m/z 351 conjugate anion by negative mode, and as a released m/z 255 carbonium ion by positive mode. Upon prolonged refrigeration, 7-SMBA accumulated an m/z 383 photooxide, which appeared capable of re-evolving the starting material as visualized by tandem quadrupole MS, or MS/MS. The 7-SMBA carbonium ion provided interpretable fragments when studied by fragment ion MS/MS, including those representing the loss of up to several protons. Subtle differences in this property were encountered upon perturbing 7-SMBA, either by warming it at 37 degrees C for 2 h or by substituting the initial sulfoxy group with an iodo group. Side-reactions accounting for such proton losses are proposed, and are of interest whether they occur in the

  17. Mass spectrometric analysis of 7-sulfoxymethyl-12-methylbenz[a]anthracene and related electrophilic polycyclic aromatic hydrocarbon metabolites.

    Science.gov (United States)

    Lehner, Andreas F; Horn, Jamie; Flesher, James W

    2004-11-01

    The Meso-region theory of polycyclic aromatic hydrocarbon (PAH) carcinogenesis predicts that the development of pronounced carcinogenicity depends on the introduction of a good leaving group on alkyl side-chains attached to the exceptionally reactive meso-anthracenic or L-region positions of PAHs. Thus, the first step in carcinogenesis by methylated PAHs such as 7,12-dimethylbenz[a]anthracene (DMBA) would be the hydroxylation of the L-region methyl groups, particularly the 7-methyl group. The second would be the formation of a metabolite, e.g. a sulfate ester, which is expected to be a good leaving group capable of generating a highly reactive benzylic carbocation. 7-Hydroxymethyl-12-methylbenz[a]anthracene (7-HMBA) is a metabolite of DMBA, and sulfation of 7-HMBA to a 7-sulfoxymethyl metabolite (7-SMBA) is a known Phase II metabolic process designed to facilitate excretion, but actually enabling more destructive side-reactions. These side-reactions occur with generation of an electrophilic 7-methylene carbonium ion, and/or by in vivo halide exchange to provide neutral side-products more capable of entering cells, especially those of DMBA target tissues. Electrospray ionization mass spectrometry (MS) enabled us to visualize 7-SMBA as an intact m/z 351 conjugate anion by negative mode, and as a released m/z 255 carbonium ion by positive mode. Upon prolonged refrigeration, 7-SMBA accumulated an m/z 383 photooxide, which appeared capable of re-evolving the starting material as visualized by tandem quadrupole MS, or MS/MS. The 7-SMBA carbonium ion provided interpretable fragments when studied by fragment ion MS/MS, including those representing the loss of up to several protons. Subtle differences in this property were encountered upon perturbing 7-SMBA, either by warming it at 37 degrees C for 2 h or by substituting the initial sulfoxy group with an iodo group. Side-reactions accounting for such proton losses are proposed, and are of interest whether they occur in the

  18. Effect of Rosmarinus officinalis in modulating 7,12-dimethylbenz(a)anthracene induced skin tumorigenesis in mice.

    Science.gov (United States)

    Sancheti, Garima; Goyal, P K

    2006-11-01

    The chemopreventive potential of rosemary (Rosmarinus officinalis) on 7,12-dimethlybenz(a)anthracene (DMBA) initiated and croton oil promoted mouse skin tumorigenesis was assessed. The modulatory effects of R. officinalis was monitored on the basis of the average latency period, tumor incidence, tumor burden, tumor yield, tumor weight and diameter as well as lipid peroxidation and glutathione level. The results indicate that R. officinalis leaves extract could prolong the latency period of tumor occurrence, decrease the tumor incidence, tumor burden and tumor yield. The average weight and diameter of tumors recorded were comparatively lower in the rosemary extract treated mouse groups. The level of lipid peroxidation was significantly reduced in blood serum and liver. Furthermore, depleted levels of glutathione were restored in RE-administered animal groups. Thus, at a dose rate of 500 mg/kg body wt/mouse, the oral administration of rosemary extract was found to be significantly protective against two-stage skin tumorigenesis. PMID:16927448

  19. Chemopreventive potential of Tribulus terrestris against 7,12- dimethylbenz (a) anthracene induced skin papillomagenesis in mice.

    Science.gov (United States)

    Kumar, Manish; Soni, Anil Kumar; Shukla, Shalini; Kumar, Ashok

    2006-01-01

    In the present investigation, the chemopreventive potential of aqueous extracts of the root and fruit of Tribulus terrestris (an Ayurvedic medicinal plant) on 7, 12 - dimethylbenz (a) anthracene (DMBA) induced papillomagenesis in male Swiss albino mice was studied. A significant reduction in tumor incidence, tumor burden and cumulative number of papillomas was observed, along with a significant increase in average latent period in mice treated orally with Tribulus terrestris suspension continuously at pre, peri and post-initiation stages of papillomagenesis as compared to the control group treated with DMBA and croton oil alone. Treatment with Tribulus terrestris suspension by oral gavage for 7 days resulted in a significant increase in the reduced glutathione content in the liver (P< 0.001 for both root and fruit extracts). Conversely, lipid peroxidation levels were significantly decreased (P< 0.001). PMID:16839225

  20. Diagnostics for specific PAHs in the far-IR: searching neutral naphthalene and anthracene in the Red Rectangle

    CERN Document Server

    Mulas, G; Joblin, C; Toublanc, D

    2006-01-01

    Context. In the framework of the interstellar polycyclic aromatic hydrocarbons (PAHs) hypothesis, far-IR skeletal bands are expected to be a fingerprint of single species in this class. Aims. We address the question of detectability of low energy PAH vibrational bands, with respect to spectral contrast and intensity ratio with ``classical'' Aromatic Infrared Bands (AIBs). Methods. We extend our extablished Monte-Carlo model of the photophysics of specific PAHs in astronomical environments, to include rotational and anharmonic band structure. The required molecular parameters were calculated in the framework of the Density Functional Theory. Results. We calculate the detailed spectral profiles of three low-energy vibrational bands of neutral naphthalene, and four low-energy vibrational bands of neutral anthracene. They are used to establish detectability constraints based on intensity ratios with ``classical'' AIBs. A general procedure is suggested to select promising diagnostics, and tested on available Infra...

  1. Pattern of distribution of dimethylbenz(a)anthracene in the Amazon molly, Poecilia formosa (Girard), after intraperitoneal injection

    Energy Technology Data Exchange (ETDEWEB)

    Woodhead, A.D.; Bornbusch, A.

    1983-01-01

    The present paper describes the distribution and accumulation labelled dimethylbenz(a)anthracene (DMBA) in the Amazon molly after intraperitoneal injection. The study was made to see whether there was preferential accumulation of the compound in the spleen; the findings showed that this was not the case. Two hours after injection, DMBA was present throughout the body, except in the brain and the ovary. There was enhanced deposition at four sites, in the macrophages of the atrium of the heart and the peritoneum, the liver and the exocrine pancreas. DMBA was taken up by reticuloendothelial macrophages for 78 h after injection, then it was lost. The accumulation and disappearance of radioactive label seen in the liver and pancreatic cells probably represented the pattern of metabolism of the compound. By 400 h after injection there was little DMBA remaining. Label accumulated in the ameloblasts, which secrete the enamel capping of the teeth. 12 references, 3 figures, 1 table.

  2. Novel “turn on” fluorescent sensors based on anthracene and carbazone units for Cu (II) ion in CH{sub 3}CN–H{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Erdemir, Serkan, E-mail: serdemir82@gmail.com; Malkondu, Sait

    2015-02-15

    Two novel anthracene-based receptors containing Schiff base and urea groups (AOC and ATC) were synthesized in one step and full characterized. The optical properties of receptors AOC and ATC towards metal ions were investigated by UV–visible and fluorescence spectroscopy. It was found that both receptors AOC and ATC show highly selectivity towards Cu{sup 2+} over other 17 metal ions in CH{sub 3}CN–H{sub 2}O (9/1, v/v). - Highlights: • Novel fluorescent sensors based on anthracene and carbazide AOC and ATC were synthesized. • The optical properties of AOC and ATC were observed by UV–visible and fluorescence spectroscopy. • AOC and ATC showed highly selective and sensitive to Cu{sup 2+} over other 17 metal ions.

  3. Mass Spectrometric Fragmentation of 1,8-Bis[4-substituted-(oxazolin-2-yl)] anthracenes: Ring-contraction Rearrangement of Oxazoline Ring under Electron-Impact Ionization Conditions

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The mass spectrometric fragmentation of 1,8-bis[4-substituted(oxazolin-2-yl)] anthracenes(AnBOXes) was investigated by using mass-analyzed ion kinetic energy spectrometry under electron-impact ionization conditions. All the compounds could undergo a ring contraction by the loss of an RCH=CH2 molecule to form 1-oxazirinyl-8-(oxazolin-2-yl) anthracene ions, which could further lose an R radical, followed by the loss of oxazoline. These ions could also eliminate an R radical and subsequently undergo ring-contraction rearrangements to lose a CHCH2O fragment and an epoxide molecule, respectively. The ions that are formed could further lose CHCH2O and CH2=CH fragments. Several ring-contraction rearrangements of the oxazoline ring were observed under electron-impact ionization conditions.

  4. Quantitative structure–activity relationships for chronic toxicity of alkyl-chrysenes and alkyl-benz[a]anthracenes to Japanese medaka embryos (Oryzias latipes)

    International Nuclear Information System (INIS)

    Highlights: • Medaka embryos were exposed to alkyl chrysenes and benzo[a]anthracenes (BAA). • Concentrations were kept constant by partition controlled delivery. • Chrysene was not toxic within solubility limits, in contrast to BAA. • Alkylation increased the toxicity of chrysene and BAA. • Toxicity was related to hydrophobicity and to specific modes of action. - Abstract: Alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) are a class of compounds found at significant concentrations in crude oils, and likely the main constituents responsible for the chronic toxicity of oil to fish. Alkyl substituents at different locations on the aromatic rings change the size and shape of PAH molecules, which results in different interactions with tissue receptors and different severities of toxicity. The present study is the first to report the toxicity of several alkylated derivatives of chrysene and benz[a]anthracene to the embryos of Japanese medaka (Oryzias latipes) using the partition controlled delivery (PCD) method of exposure. The PCD method maintained the desired exposure concentrations by equilibrium partitioning of hydrophobic test compounds from polydimethylsiloxane (PDMS) films. Test concentrations declined by only 13% over a period of 17 days. Based on the prevalence of signs of blue sac disease (BSD), as expressed by median effective concentrations (EC50s), benz[a]anthracene (B[a]A) was more toxic than chrysene. Alkylation generally increased toxicity, except at position 2 of B[a]A. Alkyl-PAHs substituted in the middle region had a lower EC50 than those substituted at the distal region. Except for B[a]A and 7-methylbenz[a]anthracene (7-MB), estimated EC50 values were higher than their solubility limits, which resulted in limited toxicity within the range of test concentrations. The regression between log EC50s and log Kow values provided a rough estimation of structure–activity relationships for alkyl-PAHs, but Kow alone did not provide a complete

  5. Pro-apoptotic and anti-inflammatory potential of andrographolide during 7,12-dimethylbenz[a]anthracene induced hamster buccal pouch carcinogenesis

    OpenAIRE

    Karthikeyan Sekar; Baskaran Nagarethinam; Arjun Kumar Singh; Manoharan Shanmugam

    2012-01-01

    Objective: Aim of the present study was to investigate the modulating effect of andrographolide on apoptotic and inflammatory markers during 7,12-dimethyl-benz[a]anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Methods: Oral tumors were developed in the buccal pouch of golden Syrian hamsters by painting with 0.5% DMBA in liquid paraffin three times a week for 14 weeks. The expression pattern of molecular markers were assayed using immunohistochemistry (p53, Bcl-2 and Bax), ELISA...

  6. Covalent functionalization of single-walled carbon nanotubes with anthracene by green chemical approach and their temperature dependent magnetic and electrical conductivity studies

    Energy Technology Data Exchange (ETDEWEB)

    Hariharasubramanian, A. [Organic Chemistry Division, School of Advanced Sciences, VIT University, Vellore 632014, Tamilnadu (India); Dominic Ravichandran, Y., E-mail: ydominic64@yahoo.co.in [Organic Chemistry Division, School of Advanced Sciences, VIT University, Vellore 632014, Tamilnadu (India); Rajesh, R.; Rajendra Kumar, K. [Organic Chemistry Division, School of Advanced Sciences, VIT University, Vellore 632014, Tamilnadu (India); Kanagaraj, M.; Arumugam, S. [Centre for High Pressure Research, School of Physics, Bharathidasan University, Thiruchirapalli 620024 (India)

    2014-01-15

    Single-walled carbon nanotubes (SWCNTs) were covalently functionalized with anthracene in molten urea by a green chemical approach. The anthracene functionalized single-walled carbon nanotubes (Ant-f-SWCNTs) were examined along with SWCNTs, using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, powder X-Ray diffraction (XRD), and scanning, and transmission electron microscopy. The observations revealed the functionalization of SWCNTs by anthracene. The temperature dependent magnetization (300–5 K) and electrical resistivity were also measured for both SWCNTs and Ant-f-SWCNTs. The electrical resistivity of Ant-f-SWCNTs at 300 K was found to be 1.27 KΩm, which is much lower than 388.55 KΩm for pristine. This indicated a 300 fold increase in conductivity at room temperature for Ant-f-SWCNTs when compared to SWCNTs. The temperature dependence of the conductivity provided an indication of the semiconducting behaviour. - Highlights: • SWCNTs were functionalized using 2-aminoanthracene by green chemistry. • Characterized by FTIR, Raman, XRD, SEM and TEM. • Temperature dependent magnetization and conductivity were investigated. • 300 fold increase in conductivity was observed for Ant-f-SWCNTs. • Semiconductor behaviour was observed in the case of Ant-f-SWCNTs.

  7. Using acetone as solvent to study removal of anthracene in soil inhibits microbial activity and alters nitrogen dynamics.

    Science.gov (United States)

    Núñez, Edgar Vázquez; Rodríguez, Viviana; Gaytán, Alejandro García; Luna-Guido, Marco; Betancur-Galvis, Liliana A; Marsch, Rodolfo; Dendooven, Luc

    2009-08-01

    Acetone is often used as a carrier to contaminate soil with polycyclic aromatic hydrocarbons (PAHs) and then to study the factors that control their removal. Acetone is an organic solvent that might affect soil processes. An alkaline saline (Texcoco soil) and an agricultural soil (Acolman soil) were amended with or without acetone, nitrogen + phosphorus (NP), and contaminated with anthracene at 520 mg/kg soil while emissions of CO2 and N2O and concentrations of NH4+, NO2(-) and NO3(-) were monitored. The CO2 emission rate decreased greater than 10 times in the soils amended with acetone. Emission of N2O decreased 70 times in the Acolman soil amended with acetone and NP and 5 times in the Texcoco soil. The concentration of NH4+ decreased in the unamended Acolman and Texcoco soil but increased when acetone was added in the first and remained constant in the latter. Acetone inhibited the increase in the amount of NO3(-) in the Acolman soil but not in the Texcoco soil. It was found that microbial activity as evidenced by the emission of CO2, nitrification, and production of N2O were inhibited by acetone. The amount of acetone used as solvent should thus be kept to a minimum, but it can be assumed that its effect on soil processes will be temporary, as microorganisms are known to repopulate soil quickly.

  8. Anthracene excimer-based "turn on" fluorescent sensor for Cr(3+) and Fe(3+) ions: Its application to living cells.

    Science.gov (United States)

    Erdemir, Serkan; Kocyigit, Ozcan

    2016-09-01

    A novel anthracene based fluorescent probe containing benzothiazole group (BFA) was designed and synthesized. The cation binding properties of BFA were studied in the presence of various cations. Both UV-vis and fluorescence spectroscopic studies indicated that BFA was highly sensitive and selective toward trivalent cations (Cr(3+) and Fe(3+)), while there was no response to monovalent, divalent cations and also Al(3+) ion. The interaction of BFA with Cr(3+) and Fe(3+) caused a significant enhancement in emission intensity due to the combination of a unique anthracenyl static excimer formation, the restricted C=N isomerization and the suppression of highly efficient photoinduced electron transfer (PET) process. The detection limits of BFA for Cr(3+) and Fe(3+) were 0.46 and 0.45µM, which presented a pronounced sensitivity toward Cr(3+) and Fe(3+), respectively. Also, possible utilization of BFA as bio-imaging fluorescent probe to detect Cr(3+) and Fe(3+) in human prostate cancer cell lines was observed by confocal fluorescence microscopy. PMID:27343579

  9. Chemopreventive potential of fungal taxol against 7, 12-dimethylbenz[a]anthracene induced mammary gland carcinogenesis in Sprague Dawley rats.

    Science.gov (United States)

    Gokul Raj, Kathamuthu; Chidambaram, Ranganathan; Varunkumar, Krishnamoorthy; Ravikumar, Vilwanathan; Pandi, Mohan

    2015-11-15

    Breast cancer is the second most prevalent cancer and foremost global public health problem. The present study was designed to appraise the chemopreventive potential of fungal taxol against 7,12-dimethylbenz[a]anthracene (DMBA) induced mammary gland carcinogenesis in Sprague Dawley rats. After 90 days of tumor induction, fungal and authentic taxol were given intraperitoneally once in a week for four weeks. Infrared thermal imaging analysis, serum biochemical parameters such as lipid peroxidase (LPO), creatinine, enzymic and non enzymic antioxidants, liver markers tests such as alanine transaminase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglycerides (TG) and lipoproteins was analysed. In addition, histopathological observation (breast, kidney and liver), immunohistochemical analysis (p53 and Her2/neu) and western blotting experiments (bcl-2, bax and caspase-9) were performed both in control and experimental animals. In thermal imaging, decreased temperature was observed in rat treated with fungal and authentic taxol when compared to tumor induced rats. The significant decrease in LPO, creatinine, ALT, AST, TC, TG, lipoproteins and increase in enzymic, non-enzymic antioxidants were exemplified in serum of treated groups. Further histopathology, immunohistochemical and western blot analysis (bax, cas-9 and bcl-2) of apoptotic markers in breast tissues clearly showed the anti-carcinogenic property of fungal taxol. Our findings implement that fungal taxol is a potential chemo preventive agent against DMBA induced mammary gland carcinogenesis.

  10. Terahertz spectroscopy and solid-state density functional theory calculation of anthracene: Effect of dispersion force on the vibrational modes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Feng; Tominaga, Keisuke, E-mail: atmyh@ntu.edu.tw, E-mail: tominaga@kobe-u.ca.jp, E-mail: junichi.nishizawa@hanken.jp [Molecular Photoscience Research Center, Kobe University, Nada, Kobe 657-0013 (Japan); Hayashi, Michitoshi, E-mail: atmyh@ntu.edu.tw, E-mail: tominaga@kobe-u.ca.jp, E-mail: junichi.nishizawa@hanken.jp; Wang, Houng-Wei [Center for Condensed Matter Sciences, National Taiwan University, 1 Roosevelt Rd., Sec. 4, Taipei 10617, Taiwan (China); Kambara, Ohki; Sasaki, Tetsuo [Research Institute of Electronics, Shizuoka University, 3-5-1 Jyohoku, Naka-ku, Hamamatsu, Shizuoka 432-8561 (Japan); Nishizawa, Jun-ichi, E-mail: atmyh@ntu.edu.tw, E-mail: tominaga@kobe-u.ca.jp, E-mail: junichi.nishizawa@hanken.jp [Jun-ichi Nishizawa Memorial Research Center, Tohoku University, 519-1176 Aoba, Aramaki, Aoba-ku, Sendai 980-0845 (Japan)

    2014-05-07

    The phonon modes of molecular crystals in the terahertz frequency region often feature delicately coupled inter- and intra-molecular vibrations. Recent advances in density functional theory such as DFT-D{sup *} have enabled accurate frequency calculation. However, the nature of normal modes has not been quantitatively discussed against experimental criteria such as isotope shift (IS) and correlation field splitting (CFS). Here, we report an analytical mode-decoupling method that allows for the decomposition of a normal mode of interest into intermolecular translation, libration, and intramolecular vibrational motions. We show an application of this method using the crystalline anthracene system as an example. The relationship between the experimentally obtained IS and the IS obtained by PBE-D{sup *} simulation indicates that two distinctive regions exist. Region I is associated with a pure intermolecular translation, whereas region II features coupled intramolecular vibrations that are further coupled by a weak intermolecular translation. We find that the PBE-D{sup *} data show excellent agreement with the experimental data in terms of IS and CFS in region II; however, PBE-D{sup *} produces significant deviations in IS in region I where strong coupling between inter- and intra-molecular vibrations contributes to normal modes. The result of this analysis is expected to facilitate future improvement of DFT-D{sup *}.

  11. Soil sterilization affects aging-related sequestration and bioavailability of p,p'-DDE and anthracene to earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Slizovskiy, Ilya B. [Program in Environmental Science and Department of Chemistry, Muhlenberg College, Allentown, PA 18104 (United States); Kelsey, Jason W., E-mail: Kelsey@muhlenberg.ed [Program in Environmental Science and Department of Chemistry, Muhlenberg College, Allentown, PA 18104 (United States)

    2010-10-15

    Laboratory experiments investigated the effects of soil sterilization and compound aging on the bioaccumulation of spiked p,p'-DDE and anthracene by Eisenia fetida and Lumbricus terrestris. Declines in bioavailability occurred as pollutant residence time in both sterile and non-sterile soils increased from 3 to 203 d. Accumulation was generally higher in sterile soils during initial periods of aging (from 3-103 d). By 203 d, however, bioavailability of the compounds was unaffected by sterilization. Gamma irradiation and autoclaving may have altered bioavailability by inducing changes in the chemistry of soil organic matter (SOM). The results support a dual-mode partitioning sorption model in which the SOM components associated with short-term sorption (the 'soft' or 'rubbery' phases) are more affected than are the components associated with long-term sorption (the 'glassy' or microcrystalline phases). Risk assessments based on data from experiments in which sterile soil was used could overestimate exposure and bioaccumulation of pollutants. - Soil sterilization affects aging-related sequestration of organic contaminants.

  12. Microemulsions of N-alkylimidazolium ionic liquid and their performance as microreactors for the photocycloaddition of 9-substituted anthracenes.

    Science.gov (United States)

    Li, Xin-Wei; Zhang, Jin; Zheng, Li-Qiang; Chen, Bin; Wu, Li-Zhu; Lv, Feng-Feng; Dong, Bin; Tung, Chen-Ho

    2009-05-19

    The phase behavior of the ternary system consisting of an ionic liquid (1-tetradecyl-3-methylimidazolium bromide [C14mim]Br), p-xylene, and water were investigated. Depending on the composition of the ternary system, formation of hexagonal and lamellar liquid crystals as well as microemulsions was observed. 1H NMR spectroscopy study, 2D ROESY spectroscopic analysis, and rheological measurements of the microemulsions indicated that p-xylene is preferably located in the hydrophobic core and the palisade shells of the microemulsions. The sizes of the microemulsion droplets for the samples with water/[C14mim]Br ratio of 78:22 are measured by both dynamic light scattering (DLS) and transmission electron microscopy with the freeze-fracture technique (FF-TEM). Upon change of the mole ratio of the solubilized xylene to [C14mim]Br from 0 to 2.4, the diameters of the microemulsion droplets increase from ca. 20 to 90 nm and size distribution gets broad. These microemulsions can solubilize and preorientate anthracene derivatives with a polar 9-substituent, and thus may enhance the head-to-head cyclomers in the photocyclization of these substrates. PMID:19432490

  13. Unexpected formation of π-expanded isoquinoline from anthracene possessing four electron-donating groups via the Duff reaction.

    Science.gov (United States)

    Węcławski, Marek K; Deperasińska, Irena; Leniak, Arkadiusz; Banasiewicz, Marzena; Kozankiewicz, Bolesław; Gryko, Daniel T

    2016-08-01

    New synthetic methods leading towards π-expanded heterocycles are sought after mainly due to their promising opto-electronic properties. Subjecting 1,5,9,10-tetramethoxyanthracene to the modern Duff reaction conditions led to the formation of a compound possessing the 2-azabenzoanthrone (dibenzo[de,h]isoquinolin-7-on) skeleton instead of the expected dialdehyde. This non-typical course of reaction can be rationalized by the double electrophilic aromatic substitution at two neighboring electron-rich positions of anthracene followed by oxidation of the resulting intermediate to form a pyridine ring. Optical studies supported by the quantum chemistry calculations indicated the lack of excited-state intramolecular proton transfer (ESIPT); for energy reasons, only one tautomeric form, with a hydrogen atom bonded to one of the two nearby oxygen atoms, was populated in the electronic ground S0 and in the excited S1 states. Nonradiative depopulation of the S1 state proceeded via internal conversion stimulated by the presence of the low frequency vibrational modes. Our serendipitous discovery represents the most complex case of rearrangement of aromatic compounds under Duff reaction conditions and could help to design analogous processes. At the same time this is the simplest method for the synthesis of derivatives of 2-azabenzoanthrone. PMID:27367169

  14. Effect of anthracene on the interaction between Platymonas helgolandica var. tsingtaoensis and Heterosigma akashiwo in laboratory cultures

    Science.gov (United States)

    Bi, Rong; Wang, You; Wang, Renjun; Li, Wei; Tang, Xuexi

    2015-02-01

    Two species of marine phytoplankton, Platymonas helgolandica var. tsingtaoensis and Heterosigma akashiwo, were cultivated in bi-algal cultures to investigate the effect of anthracene (ANT) on the interaction between them. Without ANT, H. akashiwo out-competed P. helgolandica at low initial biomass ratios ( P. helgolandica ( P): H. akashiwo ( H) = 1:4 and 1:1), but not at the highest ( P: H = 4:1). This observation was consistent with the description in Lotka-Volterra two species competition model. It was found that P. helgolandica was excluded at low initial biomass ratios, while the unstable equilibrium between two species was predicted at the highest. For both species, carrying capacity and maximal specific growth rate decreased in bi-algal cultures compared to those in monocultures. H. akashiwo exhibited a higher sensitivity to ANT than P. helgolandica. This resulted markedly in a reduced cell density of H. akashiwo but an increased cell density of P. helgolandica. Carrying capacity of P. helgolandica was consistently higher in bi-algal cultures with ANT than those without ANT, suggesting that ANT, through the elimination of H. akashiwo, generated the dominance of P. helgolandica independently of initial biomass ratios. This study showed a density-dependent effect of harmful alga ( H. akashiwo) on dietary alga ( P. helgolandica), and indicated that ocean pollutant ANT could induce the succession of marine phytoplankton.

  15. Effect of Anthracene on the Interaction BetweenPlatymonas helgolandicavar. tsingtaoensis andHeterosigma akashiwo in Laboratory Cultures

    Institute of Scientific and Technical Information of China (English)

    BI Rong; WANG You; WANG Renjun; LI Wei; TANG Xuexi

    2015-01-01

    Two species of marine phytoplankton,Platymonas helgolandicavar. tsingtaoensis andHeterosigma akashiwo, were cul-tivated in bi-algal cultures to investigate the effect of anthracene (ANT) on the interaction between them. Without ANT,H. akashiwo out-competedP. helgolandica at low initial biomass ratios (P. helgolandica (P): H. akashiwo (H)=1:4 and 1:1), but not at the highest (P:H=4:1). This observation was consistent with the description in Lotka-Volterra two species competition model. It was found that P. helgolandica was excluded at low initial biomass ratios, while the unstable equilibrium between two species was predicted at the highest. For both species, carrying capacity and maximal specific growth rate decreased in bi-algal cultures compared to those in monocultures.H. akashiwo exhibited a higher sensitivity to ANT thanP. helgolandica. This resulted markedly in a reduced cell den-sity ofH. akashiwo but an increased cell density ofP. helgolandica. Carrying capacity ofP. helgolandica was consistently higher in bi-algal cultures with ANT than those without ANT, suggesting that ANT, through the elimination ofH. akashiwo, generated the dominance ofP. helgolandica independently of initial biomass ratios. This study showed a density-dependent effect of harmful alga (H. akashiwo) on dietary alga (P. helgolandica), and indicated that ocean pollutant ANT could induce the succession of marine phytoplankton.

  16. Taurine Regulates Mitochondrial Function During 7,12-Dimethyl Benz[a]anthracene Induced Experimental Mammary Carcinogenesis

    Directory of Open Access Journals (Sweden)

    Manickam Kalappan Vanitha

    2015-09-01

    Full Text Available Objectives: The present study was undertaken to determine the modulatory effect of taurine on the liver mitochondrial enzyme system with reference to mitochondrial lipid peroxidation (LPO, antioxidants, major tricarboxylic acid cycle enzymes, and electron transport chain enzymes during 7,12-dimethyl benz[a]anthracene (DMBA induced breast cancer in Sprague-Dawley rats. Methods: Animals in which breast cancer had been induced by using DMBA (25 mg/kg body weight showed an increase in mitochondrial LPO together with decreases in enzymic antioxidants (superoxide dismutase (SOD, catalase (CAT, glutathione peroxidase (GPx, glutathione reductase (GR and glutathione-S-transferase (GST, non-enzymic antioxidants (reduced glutathione (GSH, vitamin C, and vitamin E, in citric acid cycle enzymes (isocitrate dehydrogenase (ICDH, alpha ketoglutarate dehydrogenase (alpha KDH, succinate dehydrogenase (SDH and malate dehydrogenase (MDH, and in electron transport chain (ETC complexes. Results: Taurine (100 mg/kg body weight treatment decreased liver mitochondrial LPO and augmented the activities/levels of enzymic, and non-enzymic antioxidants, tricarboxylic acid cycle enzymes and ETC complexes. Conclusion: The results of our present study demonstrated the chemotherapeutic efficacy of taurine treatment for DMBA-induced breast carcinomas.

  17. Anthracene-containing wide-band-gap conjugated polymers for high-open-circuit-voltage polymer solar cells.

    Science.gov (United States)

    Gong, Xue; Li, Cuihong; Lu, Zhen; Li, Guangwu; Mei, Qiang; Fang, Tao; Bo, Zhishan

    2013-07-25

    The synthesis, characterization, and photophysical and photovoltaic properties of two anthracene-containing wide-band-gap donor and acceptor (D-A) alternating conjugated polymers (P1 and P2) are described. These two polymers absorb in the range of 300-600 nm with a band gap of about 2.12 eV. Polymer solar cells with P1:PC71 BM as the active layer demonstrate a power conversion efficiency (PCE) of 2.23% with a high Voc of 0.96 V, a Jsc of 4.4 mA cm(-2) , and a comparable fill factor (FF) of 0.53 under simulated solar illumination of AM 1.5 G (100 mW cm(-2) ). In addition, P2:PC71 BM blend-based solar cells exhibit a PCE of 1.42% with a comparable Voc of 0.89 V, a Jsc of 3.0 mA cm(-2) , and an FF of 0.53.

  18. CO-induction of rat intestinal cancers with 7,12-dimethylbenz(a)anthracene and medroxyprogesterone acetate

    Energy Technology Data Exchange (ETDEWEB)

    Hass, G.; Galt, R.; Coogan, P.; Friese, J.

    1986-03-01

    Medroxy progesterone acetate (P) is a progestin used for treatment of sex hormone-dependent human cancers. In a study of its action, 7,12-dimethyl-benz(a)anthracene (DMBA) was given, i.g., to 50-52 day old intact or gonadectomized Sprague-Dawley rats of both sexes. Groups were given 0, 5, 25 or 100 mg of P +/- 2, .5, .1, .01 or .001 mg of 17 beta estradiol (E2), s.c., each week for 12-36 weeks. Those given P often developed, independent of sex or gonadectomy, multiple intestinal adenomas and carcinomas, especially in the jejunum. At doses of P tumor incidence was as follows: 0 mg, 2/63; 5 mg, 18/96; 25 mg, 35/57; 100 mg, 72/155. Combinations of P with doses of E2 at 2, .5 or .1 mg reduced tumor incidence 65%. At 25 or 100 mg doses of P, DMBA induction of mammary tumors was inhibited, while atrophy of ovaries and adrenal cortex was impressive. Hence, this is the only progestin, which favors DMBA induction of tumors of the rat intestine, while extinguishing mammary tumors. This matter may bear on presence of hormone receptors in human colo-rectal cancers.

  19. Enhanced susceptibility of ovaries from obese mice to 7,12-dimethylbenz[a]anthracene-induced DNA damage

    International Nuclear Information System (INIS)

    7,12-Dimethylbenz[a]anthracene (DMBA) depletes ovarian follicles and induces DNA damage in extra-ovarian tissues, thus, we investigated ovarian DMBA-induced DNA damage. Additionally, since obesity is associated with increased offspring birth defect incidence, we hypothesized that a DMBA-induced DNA damage response (DDR) is compromised in ovaries from obese females. Wild type (lean) non agouti (a/a) and KK.Cg-Ay/J heterozygote (obese) mice were dosed with sesame oil or DMBA (1 mg/kg; intraperitoneal injection) at 18 weeks of age, for 14 days. Total ovarian RNA and protein were isolated and abundance of Ataxia telangiectasia mutated (Atm), X-ray repair complementing defective repair in Chinese hamster cells 6 (Xrcc6), breast cancer type 1 (Brca1), Rad 51 homolog (Rad51), poly [ADP-ribose] polymerase 1 (Parp1) and protein kinase, DNA-activated, catalytic polypeptide (Prkdc) were quantified by RT-PCR or Western blot. Phosphorylated histone H2AX (γH2AX) level was determined by Western blotting. Obesity decreased (P < 0.05) basal protein abundance of PRKDC and BRCA1 proteins but increased (P < 0.05) γH2AX and PARP1 proteins. Ovarian ATM, XRCC6, PRKDC, RAD51 and PARP1 proteins were increased (P < 0.05) by DMBA exposure in lean mice. A blunted DMBA-induced increase (P < 0.05) in XRCC6, PRKDC, RAD51 and BRCA1 was observed in ovaries from obese mice, relative to lean counterparts. Taken together, DMBA exposure induced γH2AX as well as the ovarian DDR, supporting that DMBA causes ovarian DNA damage. Additionally, ovarian DDR was partially attenuated in obese females raising concern that obesity may be an additive factor during chemical-induced ovotoxicity. - Highlights: • DMBA induces markers of ovarian DNA damage. • Obesity induces low level ovarian DNA damage. • DMBA-induced DNA repair response is altered by obesity

  20. Enhanced susceptibility of ovaries from obese mice to 7,12-dimethylbenz[a]anthracene-induced DNA damage

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Nteeba, Jackson, E-mail: nteeba@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2014-12-01

    7,12-Dimethylbenz[a]anthracene (DMBA) depletes ovarian follicles and induces DNA damage in extra-ovarian tissues, thus, we investigated ovarian DMBA-induced DNA damage. Additionally, since obesity is associated with increased offspring birth defect incidence, we hypothesized that a DMBA-induced DNA damage response (DDR) is compromised in ovaries from obese females. Wild type (lean) non agouti (a/a) and KK.Cg-Ay/J heterozygote (obese) mice were dosed with sesame oil or DMBA (1 mg/kg; intraperitoneal injection) at 18 weeks of age, for 14 days. Total ovarian RNA and protein were isolated and abundance of Ataxia telangiectasia mutated (Atm), X-ray repair complementing defective repair in Chinese hamster cells 6 (Xrcc6), breast cancer type 1 (Brca1), Rad 51 homolog (Rad51), poly [ADP-ribose] polymerase 1 (Parp1) and protein kinase, DNA-activated, catalytic polypeptide (Prkdc) were quantified by RT-PCR or Western blot. Phosphorylated histone H2AX (γH2AX) level was determined by Western blotting. Obesity decreased (P < 0.05) basal protein abundance of PRKDC and BRCA1 proteins but increased (P < 0.05) γH2AX and PARP1 proteins. Ovarian ATM, XRCC6, PRKDC, RAD51 and PARP1 proteins were increased (P < 0.05) by DMBA exposure in lean mice. A blunted DMBA-induced increase (P < 0.05) in XRCC6, PRKDC, RAD51 and BRCA1 was observed in ovaries from obese mice, relative to lean counterparts. Taken together, DMBA exposure induced γH2AX as well as the ovarian DDR, supporting that DMBA causes ovarian DNA damage. Additionally, ovarian DDR was partially attenuated in obese females raising concern that obesity may be an additive factor during chemical-induced ovotoxicity. - Highlights: • DMBA induces markers of ovarian DNA damage. • Obesity induces low level ovarian DNA damage. • DMBA-induced DNA repair response is altered by obesity.

  1. Aggressive mammary carcinoma progression in Nrf2 knockout mice treated with 7,12-dimethylbenz[a]anthracene

    International Nuclear Information System (INIS)

    Activation of nuclear factor erythroid 2-related factor (Nrf2), which belongs to the basic leucine zipper transcription factor family, is a strategy for cancer chemopreventive phytochemicals. It is an important regulator of genes induced by oxidative stress, such as glutathione S-transferases, heme oxygenase-1 and peroxiredoxin 1, by activating the antioxidant response element (ARE). We hypothesized that (1) the citrus coumarin auraptene may suppress premalignant mammary lesions via activation of Nrf2/ARE, and (2) that Nrf2 knockout (KO) mice would be more susceptible to mammary carcinogenesis. Premalignant lesions and mammary carcinomas were induced by medroxyprogesterone acetate and 7,12-dimethylbenz[a]anthracene treatment. The 10-week pre-malignant study was performed in which 8 groups of 10 each female wild-type (WT) and KO mice were fed either control diet or diets containing auraptene (500 ppm). A carcinogenesis study was also conducted in KO vs. WT mice (n = 30-34). Comparisons between groups were evaluated using ANOVA and Kaplan-Meier Survival statistics, and the Mann-Whitney U-test. All mice treated with carcinogen exhibited premalignant lesions but there were no differences by genotype or diet. In the KO mice, there was a dramatic increase in mammary carcinoma growth rate, size, and weight. Although there was no difference in overall survival, the KO mice had significantly lower mammary tumor-free survival. Also, in the KO mammary carcinomas, the active forms of NF-κB and β-catenin were increased ~2-fold whereas no differences in oxidized proteins were observed. Many other tumors were observed, including lymphomas. Interestingly, the incidences of lung adenomas in the KO mice were significantly higher than in the WT mice. We report, for the first time, that there was no apparent difference in the formation of premalignant lesions, but rather, the KO mice exhibited rapid, aggressive mammary carcinoma progression

  2. Inhibition of 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis by S-allylcysteine.

    Science.gov (United States)

    Balasenthil, S; Nagini, S

    2000-07-01

    Consumption of garlic has been reported to be associated with decreased risk of cancer. We used the 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinoma model to assess the oral chemopreventive potential of S-allylcysteine (SAC), a water-soluble constituent of garlic. Hamsters were divided into four groups of six animals each. The right buccal pouches of the animals in group I were painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in group II were painted with DMBA as in group I and in addition received 200 mg/kg body weight SAC intragastrically three times a week on days alternate to DMBA application. Group III animals received SAC as in group II. Animals in group IV received neither DMBA nor SAC and served as control. The hamsters were killed after an experimental period of 14 weeks. Biochemical measurements were carried out on tumour and normal pouch tissues. Measurement of lipid peroxidation, reduced glutathione (GSH), glutathione peroxidase (GPx) and glutathione S-transferase (GST) was used to monitor the chemopreventive potential of SAC. All hamsters painted with DMBA alone for 14 weeks developed well-differentiated squamous cell carcinomas. Diminished lipid peroxidation in the oral tumour tissue was accompanied by a significant increase in the levels of GSH, GPx and GST. Administration of SAC significantly suppressed DMBA-induced oral carcinogenesis as revealed by the absence of neoplasms. The results of the present study suggest that garlic may exert its chemopreventive effects by modulating lipid peroxidation and enhancing the levels of GSH, GPx and GST. PMID:10899678

  3. S-allylcysteine, a garlic constituent, inhibits 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

    Science.gov (United States)

    Balasenthil, S; Ramachandran, C R; Nagini, S

    2001-01-01

    The effect of S-allylcysteine (SAC), a water-soluble garlic constituent, on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis was investigated in male Syrian hamstes. Forty hamsters were divided into 4 groups of 10 animals. The right buccal pouches of the animals in Group I were painted with a 0.5% solution of DMBA in liquid paraffin three times a week. The animals in Group II were painted with DMBA as in Group I and, in addition, received 200 mg/kg body wt p.o. SAC three times a week on days alternate to DMBA application. Group III animals received SAC as in Group II. Group IV animals received neither DMBA nor SAC and served as the control. The hamsters were killed after an experimental period of 14 wk. Measurement of lipid peroxidation, the antioxidant enzymes superoxide dismutase (SOD) and catalase, in the buccal pouch mucosa, liver, and circulation was used to monitor the chemopreventive potential of SAC. All hamsters painted with DMBA alone developed tumors identified histologically as well-differentiated squamous cell carcinomas. In hamsters bearing DMBA-induced buccal pouch tumors, diminished lipid peroxidation in the tumor tissue was accompanied by decreased activities of SOD and catalase, whereas in the liver and circulation, enhanced lipid peroxidation was associated with compromised antioxidant defenses. Administration of SAC suppressed the incidence of DMBA-induced HBP tumors as revealed by the absence of carcinomas. Histologically, only keratosis was observed. SAC modulated DMBA-induced decreased susceptibility of the HBP to lipid peroxidation while simultaneously enhancing SOD and catalase activities, whereas in the liver and circulation, SAC decreased the extent of lipid peroxidation and significantly enhanced antioxidant activities. We suggest that SAC exerts its chemopreventive effects by modulating lipid peroxidation and enhancing antioxidant activities in the target organ as well as in the liver and

  4. Aggressive mammary carcinoma progression in Nrf2 knockout mice treated with 7,12-dimethylbenz[a]anthracene

    Directory of Open Access Journals (Sweden)

    Yamamoto Masayuki

    2010-10-01

    Full Text Available Abstract Background Activation of nuclear factor erythroid 2-related factor (Nrf2, which belongs to the basic leucine zipper transcription factor family, is a strategy for cancer chemopreventive phytochemicals. It is an important regulator of genes induced by oxidative stress, such as glutathione S-transferases, heme oxygenase-1 and peroxiredoxin 1, by activating the antioxidant response element (ARE. We hypothesized that (1 the citrus coumarin auraptene may suppress premalignant mammary lesions via activation of Nrf2/ARE, and (2 that Nrf2 knockout (KO mice would be more susceptible to mammary carcinogenesis. Methods Premalignant lesions and mammary carcinomas were induced by medroxyprogesterone acetate and 7,12-dimethylbenz[a]anthracene treatment. The 10-week pre-malignant study was performed in which 8 groups of 10 each female wild-type (WT and KO mice were fed either control diet or diets containing auraptene (500 ppm. A carcinogenesis study was also conducted in KO vs. WT mice (n = 30-34. Comparisons between groups were evaluated using ANOVA and Kaplan-Meier Survival statistics, and the Mann-Whitney U-test. Results All mice treated with carcinogen exhibited premalignant lesions but there were no differences by genotype or diet. In the KO mice, there was a dramatic increase in mammary carcinoma growth rate, size, and weight. Although there was no difference in overall survival, the KO mice had significantly lower mammary tumor-free survival. Also, in the KO mammary carcinomas, the active forms of NF-κB and β-catenin were increased ~2-fold whereas no differences in oxidized proteins were observed. Many other tumors were observed, including lymphomas. Interestingly, the incidences of lung adenomas in the KO mice were significantly higher than in the WT mice. Conclusions We report, for the first time, that there was no apparent difference in the formation of premalignant lesions, but rather, the KO mice exhibited rapid, aggressive mammary

  5. Caribbean yellow band disease compromises the activity of catalase and glutathione S-transferase in the reef-building coral Orbicella faveolata exposed to anthracene.

    Science.gov (United States)

    Montilla, Luis Miguel; Ramos, Ruth; García, Elia; Cróquer, Aldo

    2016-05-01

    Healthy and diseased corals are threatened by different anthropogenic sources, such as pollution, a problem expected to become more severe in the near future. Despite the fact that coastal pollution and coral diseases might represent a serious threat to coral reef health, there is a paucity of controlled experiments showing whether the response of diseased and healthy corals to xenobiotics differs. In this study, we exposed healthy and Caribbean yellow band disease (CYBD)-affected Orbicella faveolata colonies to 3 sublethal concentrations of anthracene to test if enzymatic responses to this hydrocarbon were compromised in CYBD-affected tissues. For this, a 2-factorial fully orthogonal design was used in a controlled laboratory bioassay, using tissue condition (2 levels: apparently healthy and diseased) and pollutant concentration (4 levels: experimental control, 10, 30 and 100 ppb concentration) as fixed factors. A permutation-based ANOVA (PERMANOVA) was used to test the effects of condition and concentration on the specific activity of 3 enzymatic biomarkers: catalase, glutathione S-transferase, and glutathione peroxidase. We found a significant interaction between the concentration of anthracene and the colony condition for catalase (Pseudo-F = 3.84, df = 3, p < 0.05) and glutathione S-transferase (Pseudo-F = 3.29, df = 3, p < 0.05). Moreover, our results indicated that the enzymatic response to anthracene in CYBD-affected tissues was compromised, as the activity of these enzymes decreased 3- to 4-fold compared to healthy tissues. These results suggest that under a potential scenario of increasing hydrocarbon coastal pollution, colonies of O. faveolata affected with CYBD might become more vulnerable to the deleterious effects of chemical pollution.

  6. Supramolecular Self-Assembly of Histidine-Capped-Dialkoxy-Anthracene: A Visible Light Triggered Platform for facile siRNA Delivery

    KAUST Repository

    Patil, Sachin

    2016-06-29

    Supramolecular self-assembly of histidine-capped-dialkoxy-anthracene (HDA) results in the formation of light responsive nanostructures.Single-crystal X-ray diffraction analysis of HDA shows two types of hydrogen bonding. The first hydrogen bond is established between the imidazole moieties while the second involves the oxygen atom of one amide group and the hydrogen atom of a second amide group. When protonated in acidic aqueous media, HDA successfully complexes siRNA yielding spherical nanostructures. This biocompatible platform controllably delivers siRNA with high efficacy upon visible light irradiation leading up to 90% of gene silencing in live cells.

  7. Miscibility of Two Components in a Binary Mixture of 9-Phenyl Anthracene Mixed with Stearic Acid or Polymethyl Methacrylate at Air-Water Interface

    Institute of Scientific and Technical Information of China (English)

    P. K. Paul; Md. N. Islam; D. Bhattacharjee; S. A. Hussain

    2007-01-01

    We report the miscibility characteristics of two components in a binary mixture of 9-phenyl anthracene (PA) mixed with stearic acid (SA) or polymethyl methacrylate (PMMA). The behaviour of surface pressure versus area per molecule isotherms reveal that the area per molecule decreases systematically with increasing molefractions of PA. The characteristics of areas per molecule versus molefractions and collapse pressure vs molefraction indicate that various interactions involved among the sample and matrix molecules. The interaction scheme is found to change with the change in surface pressure and molefraction of mixing. Scanning electron microscopic study confirms the aggregation of PA molecules in the mixed films.

  8. Effects of UVB and 7, 12, dimethylbenz(alpha)anthracene (DMBA) on epidermal melanocytes of the tail in C57BL mice

    Energy Technology Data Exchange (ETDEWEB)

    Blog, F.B.; Szabo, G.

    1979-12-01

    The morphological and numerical changes in the epidermal melanocyte system of the tail of C57BL mice were studied after exposure to 7, 12, dimethylbenz(alpha)anthracene(DMBA) followed by UVB irradiation. Biopsies were studied by the combined skin-splitting DOPA and electron microscopic techniques. After 10 weeks of DMBA treatment the following changes were observed: the original brick-like arrangement of melanocytes became confluent, melanocytes were irregularly shaped, dendrites shortened and clumped together, and the outer root sheaths of the hair follicles became covered with melanocytes. Damage of melanocytes by the DMBA treatment was seen, but no inflammation or tumor formation was observed.

  9. Quantitative structure–activity relationships for chronic toxicity of alkyl-chrysenes and alkyl-benz[a]anthracenes to Japanese medaka embryos (Oryzias latipes)

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Hongkang [Department of Biology, Queen' s University, Kingston, Ontario K7L3N6 (Canada); Morandi, Garrett D. [School of Environmental Studies, Queen' s University, Kingston, Ontario K7L3N6 (Canada); Brown, R. Stephen [School of Environmental Studies, Queen' s University, Kingston, Ontario K7L3N6 (Canada); Department of Chemistry, Queen' s University, Kingston, Ontario K7L3N6 (Canada); Snieckus, Victor; Rantanen, Toni [Department of Chemistry, Queen' s University, Kingston, Ontario K7L3N6 (Canada); Jørgensen, Kåre B. [Department of Mathematics and Natural Sciences, University of Stavanger, 4036 Stavanger (Norway); Hodson, Peter V., E-mail: peter.hodson@queensu.ca [Department of Biology, Queen' s University, Kingston, Ontario K7L3N6 (Canada); School of Environmental Studies, Queen' s University, Kingston, Ontario K7L3N6 (Canada)

    2015-02-15

    Highlights: • Medaka embryos were exposed to alkyl chrysenes and benzo[a]anthracenes (BAA). • Concentrations were kept constant by partition controlled delivery. • Chrysene was not toxic within solubility limits, in contrast to BAA. • Alkylation increased the toxicity of chrysene and BAA. • Toxicity was related to hydrophobicity and to specific modes of action. - Abstract: Alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) are a class of compounds found at significant concentrations in crude oils, and likely the main constituents responsible for the chronic toxicity of oil to fish. Alkyl substituents at different locations on the aromatic rings change the size and shape of PAH molecules, which results in different interactions with tissue receptors and different severities of toxicity. The present study is the first to report the toxicity of several alkylated derivatives of chrysene and benz[a]anthracene to the embryos of Japanese medaka (Oryzias latipes) using the partition controlled delivery (PCD) method of exposure. The PCD method maintained the desired exposure concentrations by equilibrium partitioning of hydrophobic test compounds from polydimethylsiloxane (PDMS) films. Test concentrations declined by only 13% over a period of 17 days. Based on the prevalence of signs of blue sac disease (BSD), as expressed by median effective concentrations (EC50s), benz[a]anthracene (B[a]A) was more toxic than chrysene. Alkylation generally increased toxicity, except at position 2 of B[a]A. Alkyl-PAHs substituted in the middle region had a lower EC50 than those substituted at the distal region. Except for B[a]A and 7-methylbenz[a]anthracene (7-MB), estimated EC50 values were higher than their solubility limits, which resulted in limited toxicity within the range of test concentrations. The regression between log EC50s and log K{sub ow} values provided a rough estimation of structure–activity relationships for alkyl-PAHs, but K{sub ow} alone did not provide

  10. Protective role for ovarian glutathione S-transferase isoform pi during 7,12-dimethylbenz[a]anthracene-induced ovotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Poulomi, E-mail: poulomib@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2012-04-15

    7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles at all developmental stages. This study investigated a role for the glutathione S-transferase (Gst) isoforms alpha (a), mu (m) and pi (p) and the transcription factors, Ahr and Nrf2, during DMBA-induced ovotoxicity, and their regulation by phosphatidylinositol-3 kinase (PI3K) signaling. Negative regulation of JNK by GSTP during DMBA exposure was also studied. Post-natal day (PND) 4 Fischer 344 rat ovaries were exposed to vehicle control (1% DMSO) ± DMBA (1 μM) or vehicle control (1% DMSO) ± LY294002 (PI3K inhibitor; 20 μM) for 1, 2, 4, or 6 days. Total RNA or protein was isolated, followed by RT-PCR or Western blotting to determine mRNA or protein level, respectively. Immunoprecipitation using an anti-GSTP antibody was performed to determine interaction between GSTP and JNK, followed by Western blotting to determine JNK and p-c-Jun protein level. DMBA had no impact on Gsta, Gstm or Nrf2 mRNA level, but increased Gstp mRNA and protein after 2 days. Ahr mRNA and protein increased after 2 and 4 days of DMBA exposure, respectively and DMBA increased NRF2 protein level after 4 days. JNK bound to GSTP was increased during DMBA exposure, with a concomitant decrease in unbound JNK and p-c-Jun. Ahr and Gstp mRNA were decreased (2 days) and increased (4 days) by PI3K inhibition, while Gstm mRNA increased (P < 0.05) after both time points, and there was no effect on Nrf2 mRNA. PI3K inhibition increased AHR, NRF2 and GSTP protein level. These findings support involvement of ovarian GSTP during DMBA exposure, and indicate a regulatory role for the PI3K signaling pathway on ovarian xenobiotic metabolism gene expression. -- Highlights: ► Ovarian GSTP is activated in response to DMBA exposure. ► AhR and Nrf2 transcription factors are up-regulated by DMBA. ► PI3K signaling regulates Ahr, Nrf2 and Gstp expression. ► GSTP negatively regulates ovarian JNK in response to DMBA exposure.

  11. 7,12-Dimethylbenz[a]anthracene exposure induces the DNA repair response in neonatal rat ovaries

    International Nuclear Information System (INIS)

    7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles at all stages of development. This study investigated DMBA-induced DNA double strand break (DSB) formation with subsequent activation of the ovarian DNA repair response in models of pre-antral or pre-ovulatory follicle loss. Postnatal day (PND) 4 Fisher 344 (F344) rat ovaries were cultured for 4 days followed by single exposures of vehicle control (1% DMSO) or DMBA (12.5 nM or 75 nM) and maintained in culture for 4 or 8 days. Alternately, PND4 F344 rat ovaries were exposed to 1 μM DMBA at the start of culture for 2 days. Total RNA or protein was isolated, followed by qPCR or Western blotting to quantify mRNA or protein level, respectively. γH2AX and phosphorylated ATM were localized and quantified using immunofluorescence staining. DMBA exposure increased caspase 3 and γH2AX protein. Additionally, DMBA (12.5 nM and 1 μM) increased levels of mRNA encoding Atm, Xrcc6, Brca1 and Rad51. In contrast, Parp1 mRNA was decreased on d4 and increased on d8 of DMBA exposure, while PARP1 protein increased after 8 days of DMBA exposure. Total ATM increased in a concentration-dependent temporal pattern (75 nM d4; 12.5 nM d8), while pATM was localized in large primary and secondary follicles and increased after 8 days of 75 nM DMBA exposure compared to both control and 12.5 nM DMBA. These findings support that, despite some concentration effects, DMBA induces ovarian DNA damage and that DNA repair mechanisms are induced as a potential mechanism to prevent follicle loss. - Highlights: • DMBA exposure increases ovarian caspase-3 protein expression. • DMBA exposure increases the γH2AX protein in oocytes. • DMBA exposure activates a DNA repair response in the ovary

  12. Trianthema portulacastrum Linn. exerts chemoprevention of 7,12-dimethylbenz(a)anthracene-induced mammary tumorigenesis in rats

    Energy Technology Data Exchange (ETDEWEB)

    Bishayee, Anupam, E-mail: abishayee@auhs.edu [Department of Pharmaceutical Sciences, School of Pharmacy, American University of Health Sciences, Signal Hill, CA 90755 (United States); Mandal, Animesh [Cancer Therapeutics and Chemoprevention Group, Department of Pharmaceutical Sciences, College of Pharmacy, Northeast Ohio Medical University, Rootstown, OH 44272 (United States)

    2014-10-15

    Highlights: • Dietary administration of an ethanolic extract of aerial parts of T. portulacastrum (TPE) exhibits a striking chemopreventive effect in an experimentally induced classical animal model of breast cancer. • The mammary tumor-inhibitory effect of TPE could be achieved, at least in part, though intervention of key hallmark capabilities of tumor cells, such as abnormal cell proliferation and evasion of apoptosis. • TPE is capable of diminishing activated canonical Wnt/β-catenin signaling to exhibit antiproliferative, proapoptotic and oncostatic effects during this early-stage mammary carcinoma. • These results coupled with a safety profile of T. portulacastrum may encourage further studies to understand the full potential of this dietary plant for chemoprevention of breast cancer. - Abstract: Due to limited treatment options for advanced-stage metastatic breast cancer, a high priority should be given to develop non-toxic chemopreventive drugs. The value of various natural and dietary agents to reduce the risk of developing breast cancer is well established. Trianthema portulacastrum Linn. (Aizoaceae), a dietary and medicinal plant, has been found to exert antihepatotoxic and antihepatocarcinogenic properties in rodents. This study was initiated to investigate mechanism-based chemopreventive potential of an ethanolic extract of T. portulacastrum (TPE) against 7,12-dimethylbenz(a)anthracene (DMBA)-initiated rat mammary gland carcinogenesis, an experimental tumor model that closely resembles human breast cancer. Rats had access to a basal diet supplemented with TPE to yield three dietary doses of the extract, i.e., 50, 100 and 200 mg/kg body weight. Following two weeks of TPE treatment, mammary tumorigenesis was initiated by oral administration of DMBA (50 mg/kg body weight). At the end of the study (16 weeks after DMBA exposure), TPE exhibited a striking reduction of DMBA-induced mammary tumor incidence, total tumor burden and average tumor weight

  13. UVA Photoirradiation of Oxygenated Benz[a]anthracene and 3-Methylcholanthene - Generation of Singlet Oxygen and Induction of Lipid Peroxidation

    Directory of Open Access Journals (Sweden)

    Diógenes Herreño Sáenz

    2008-03-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs are widespread genotoxic environmental pollutants and potentially pose a health risk to humans. Although the biological and toxicological activities, including metabolism, mutagenicity, and carcinogenicity, of PAHs have been thoroughly studied, their phototoxicity and photo-induced biological activity have not been well examined. We have long been interested in phototoxicity of PAHs and their derivatives induced by irradiation with UV light. In this paper we report the photoirradiation of a series of oxygenated benz[a]anthracene (BA and 3-methylcholanthene (3-MC by UVA light in the presence of a lipid, methyl linoleate. The studied PAHs include 2-hydroxy-BA (2-OH-BA, 3-hydroxy-BA (3-OH-BA, 5-hydroxymethyl-BA (5-CH2OH-BA, 7-hydroxymethyl-BA (7-CH2OH-BA, 12-hydroxymethyl-BA (12-CH2OH-BA, 7-hydroxymethyl-12-methyl-BA (7-CH2OH-12-MBA, 5-formyl-BA (5-CHO-BA, BA 5,6-cis-dihydrodiol (BA 5,6-cis-diol, 1-hydroxy-3- methylcholanthene (1-OH-3-MC, 1-keto-3-methylcholanthene (1-keto-3-MC, and 3-MC 1,2-diol. The results indicate that upon photoirradiation by UVA at 7 and 21 J/cm2, respectively all these compounds induced lipid peroxidation and exhibited a relationship between the dose of the light and the level of lipid peroxidation induced. To determine whether or not photoirradiation of these compounds by UVA light produces ROS, an ESR spin-trap technique was employed to provide direct evidence. Photoirradiation of 3-keto-3-MC by UVA (at 389 nm in the presence of 2,2,6,6-tetramethylpiperidine (TEMP, a specific probe for singlet oxygen, resulted in the formation of TEMPO, indicating that singlet oxygen was generated. These overall results suggest that UVA photoirradiation of oxygenated BA and 3-methylcholanthrene generates singlet oxygen, one of the reactive oxygen species (ROS, which induce lipid peroxidation.

  14. Impact of 7,12-dimethylbenz[a]anthracene exposure on connexin gap junction proteins in cultured rat ovaries

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2014-01-15

    7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles in a concentration-dependent manner. The impact of DMBA on connexin (CX) proteins that mediate communication between follicular cell types along with pro-apoptotic factors p53 and Bax were investigated. Postnatal day (PND) 4 Fisher 344 rat ovaries were cultured for 4 days in vehicle medium (1% DMSO) followed by a single exposure to vehicle control (1% DMSO) or DMBA (12.5 nM or 75 nM) and cultured for 4 or 8 days. RT-PCR was performed to quantify Cx37, Cx43, p53 and Bax mRNA level. Western blotting and immunofluorescence staining were performed to determine CX37 or CX43 level and/or localization. Cx37 mRNA and protein increased (P < 0.05) at 4 days of 12.5 nM DMBA exposure. Relative to vehicle control-treated ovaries, mRNA encoding Cx43 decreased (P < 0.05) but CX43 protein increased (P < 0.05) at 4 days by both DMBA exposures. mRNA expression of pro-apoptotic p53 was decreased (P < 0.05) but no changes in Bax expression were observed after 4 days of DMBA exposures. In contrast, after 8 days, DMBA decreased Cx37 and Cx43 mRNA and protein but increased both p53 and Bax mRNA levels. CX43 protein was located between granulosa cells, while CX37 was located at the oocyte cell surface of all follicle stages. These findings support that DMBA exposure impacts ovarian Cx37 and Cx43 mRNA and protein prior to both observed changes in pro-apoptotic p53 and Bax and follicle loss. It is possible that such interference in follicular cell communication is detrimental to follicle viability, and may play a role in DMBA-induced follicular atresia. - Highlights: • DMBA increases Cx37 and Cx43 expression prior to follicle loss. • During follicle loss both Cx37 and Cx43 expressions are reduced. • CX43 protein is absent in follicle remnants lacking an oocyte.

  15. Anthracene coupled thiourea as a colorimetric sensor for F{sup −}/Cu{sup 2+} and fluorescent sensor for Hg{sup 2+}/picric acid

    Energy Technology Data Exchange (ETDEWEB)

    Udhayakumari, Duraisamy [Organic and Polymer Synthesis Laboratory, Department of Chemistry, National Institute of Technology, Tiruchirappalli-620 015 (India); Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan, ROC (China); Velmathi, Sivan, E-mail: velmathis@nitt.edu [Organic and Polymer Synthesis Laboratory, Department of Chemistry, National Institute of Technology, Tiruchirappalli-620 015 (India); Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan, ROC (China); Venkatesan, Parthiban; Wu, Shu-Pao [Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan, ROC (China)

    2015-05-15

    A new dual chemosensor (Z)-2-(anthracen-9-ylmethylene)-N-phenylhydrazinecarbothioamide R1 was synthesized by incorporating a thiourea derivative as a binding unit and an anthracene group as a fluorescence signalling unit. R1 selectively binds with Cu{sup 2+} and Hg{sup 2+} ions in aqueous medium. R1 exhibits highly selective recognition towards F{sup −} ion and picric acid in organic medium. Fluorescence quenching was observed in case of R1 with Cu{sup 2+} and Hg{sup 2+} ions over commonly coexistent metal ions. Furthermore, fluorescence imaging experiments of Cu{sup 2+} and Hg{sup 2+} ions in living RAW 264.7 cells demonstrate its value of practical applications in biological systems. - Highlights: • R1 exhibited highly selective recognition towards Cu{sup 2+}, Hg{sup 2+} and F{sup −} ions. • The anion detection by R1 is further confirmed by {sup 1}H NMR titration method. • Detection of Cu{sup 2+} and Hg{sup 2+} ion in the living cell was achieved using fluorescence microscope. • R1 selectively sense picric acid over other nitroaromatics.

  16. Characterization and determination of the thermodynamic and kinetic properties of the adsorption of molybdenum (VI) onto microcrystalline anthracene modified with 8-hydroxyquinoline

    International Nuclear Information System (INIS)

    A reliable and effective method for the determination of trace molybdenum in effluents is proposed. Molybdenum (VI) is analyzed by Microwave Plasma Torch Optical Emission Spectrometry (MPT-OES) based on the adsorption collection onto microcrystalline anthracene modified with 8-hydroxyquinoline. The possible reaction mechanism was discussed in detail and the optimum conditions for adsorption of Mo (VI) were confirmed. The experimental data were fitted well with the pseudo-second-order kinetic model and Langmuir model at all studied temperatures. The calculated thermodynamic parameters (ΔGT, ΔHT and ΔST) showed that the adsorption of molybdenum onto microcrystalline anthracene was feasible, spontaneous and endothermic at 280-320 K. The recovery of this method is in the range of 96.5%-103.3% with preconcentration factor of 100 and the limit detection after preconcentration is 0.078 μg L-1. The proposed method has been successfully applied to the determination of trace Mo (VI) in environmental water samples with satisfactory results. Highlights: → The preparation of the sorbent, MICRO-AN-8-hydroxyquinoline, is relatively simple. → Excellent properties of the sorbent have been illustrated in detail. → Exhaustive data concerning Mo(VI) adsorption behavior are provided. → Adsorption mechanism is firstly discussed from the view of ion-exchange reaction. → Offer reference for the studies on other metal ions adsorption onto the sorbent.

  17. Full-dimensional multilayer multiconfigurational time-dependent Hartree study of electron transfer dynamics in the anthracene/C60 complex

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yu; Zheng, Jie; Lan, Zhenggang, E-mail: lanzg@qibebt.ac.cn [CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101 (China); University of Chinese Academy of Sciences, Beijing 100049 (China)

    2015-02-28

    Electron transfer at the donor-acceptor heterojunctions plays a critical role in the photoinduced process during the solar energy conversion in organic photovoltaic materials. We theoretically investigate the electron transfer process in the anthracene/C60 donor-acceptor complex by using quantum dynamics calculations. The electron-transfer model Hamiltonian with full dimensionality was built by quantum-chemical calculations. The quantum dynamics calculations were performed using the multiconfigurational time-dependent Hartree (MCTDH) theory and multilayer (ML) MCTDH methods. The latter approach (ML-MCTDH) allows us to conduct the comprehensive study on the quantum evolution of the full-dimensional electron-transfer model including 4 electronic states and 246 vibrational degrees of freedom. Our quantum dynamics calculations exhibit the ultrafast anthracene → C60 charge transfer process because of the strong coupling between excitonic and charge transfer states. This work demonstrates that the ML-MCTDH is a very powerful method to treat the quantum evolution of complex systems.

  18. Determination of the Residual Anthracene Concentration in Cultures of Haloalkalitolerant Actinomycetes by Excitation Fluorescence, Emission Fluorescence, and Synchronous Fluorescence: Comparative Study

    Directory of Open Access Journals (Sweden)

    Reyna del Carmen Lara-Severino

    2016-01-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs are compounds that can be quantified by fluorescence due to their high quantum yield. Haloalkalitolerant bacteria tolerate wide concentration ranges of NaCl and pH. They are potentially useful in the PAHs bioremediation of saline environments. However, it is known that salinity of the sample affects fluorescence signal regardless of the method. The objective of this work was to carry out a comparative study based on the sensitivity, linearity, and detection limits of the excitation, emission, and synchronous fluorescence methods, during the quantification of the residual anthracene concentration from the following haloalkalitolerant actinomycetes cultures Kocuria rosea, Kocuria palustris, Microbacterium testaceum, and 4 strains of Nocardia farcinica, in order to establish the proper fluorescence method to study the PAHs biodegrading capacity of haloalkalitolerant actinobacteria. The study demonstrated statistical differences among the strains and among the fluorescence methods regarding the anthracene residual concentration. The results showed that excitation and emission fluorescence methods performed very similarly but sensitivity in excitation fluorescence is slightly higher. Synchronous fluorescence using Δλ=150 nm is not the most convenient method. Therefore we propose the excitation fluorescence as the fluorescence method to be used in the study of the PAHs biodegrading capacity of haloalkalitolerant actinomycetes.

  19. Trace Copper Determination in Environmental Samples via Separation and Preconcentration on Microcrystalline Anthracene%微晶蒽分离富集测定痕量铜(Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    王旭; 郑立庆; 李全民

    2011-01-01

    建立了一种利用微晶蒽吸附分离富集环境水样中痕量Cu(Ⅱ)的新方法.研究表明,pH =3.0时,Cu(Ⅱ)与1-(2-吡啶偶氮)-2-萘酚形成红棕色螯合物被微晶蒽定量吸附,而Pb(Ⅱ)、in(Ⅱ)、Co(Ⅱ)、Ni(Ⅱ)、Cd(Ⅱ)、Zn(Ⅱ)、Fe(Ⅲ)和Al(Ⅲ)等完全留在溶液中,从而实现Cu(Ⅱ)与它们的分离.该方法可直接用于1L水样中痕量Cu(Ⅱ)的分离与富集,富集倍数达200倍,回收率91.0%~104.0%,最低检出限为0.026 μg/L;应用于不同水样中Cu(Ⅱ)的测定,结果令人满意.%A new method using microcrystalline anthracene as an adsorbent to separate and preconcentrate trace copper in environmental water samples has been developed. Effects of different parameters, such as the acidity, types of salt, amounts of l-(2-pyridylazo)-2-naphthol( PAN) and anthracene, preconcentration time, etc. On the enrichment yield of Cu(II) have been investigated. The results indicate that at pH =3. 00, a red chelate complex generated by the reaction between Cu( II ) and PAN can be quantitatively adsorbed on the surface of microcrystalline anthracene, whereas Pb(II) , Mn( D), Co(E), Ni(II), Cd(II), Zn(fl), Fe(Ⅲ), Al(Ⅲ) etc. Completely remain in the solution. Therefore, the aim of separation and preconcentration of trace copper could be achieved. The possible reaction mechanism of the enrichment of copper is discussed in detail in this paper. The recovery is in the range of 91. 0% ~ 104. 0% with the enrichment factor of 200. The limit of detection after preconcentration is 0. 026 μg/L. The proposed method could be directly applied to the determination of trace copper in different environmental water samples of large volume( 1 L) with satisfactory results.

  20. Therapeutic effect of centchroman alone and in combination with glycine soya on 7,12-dimethylbenz[alpha]anthracene-induced breast tumor in rat.

    Science.gov (United States)

    Mishra, Rajeev; Tiwari, Ashutosh; Bhadauria, Smrati; Mishra, Jyoti; Murthy, P K; Murthy, P S R

    2010-06-01

    Centchroman is a non-steroidal oral contraceptive and has been found to be a candidate drug for breast cancer exhibiting partial to complete remission of lesions in 40.5% of breast cancer patients. The therapeutic efficacy of centchroman was monitored alone and together with glycine soya on growth of 7,12-dimethylbenz[alpha]anthracene-induced breast tumor in rat. The tumor regression was monitored at different doses of centchroman alone ranging from 0 to 10 mg kg(-1) and with glycine soya from 1x10(4) to 5x10(4) mg kg(-1) per day until 5weeks treatment. An optimum tumor treatment opus was established with varying treatment parameters including doses of therapeutic agents and treatment period. The tumors were found to be static with a strong anti-estrogenic effect. Overall our study shows that both centchroman and glycine soya alone and jointly combat with breast cancer.

  1. Evolution of energy deposition processes in anthracene single crystal from photochemistry to radiation chemistry under excitation with synchrotron radiation from 3 to 700 eV

    International Nuclear Information System (INIS)

    Absolute values of quantum yield Φ(hν) of singlet exciton formation in anthracene single crystals were measured as a function of photon energy hν, with the usage of synchrotron radiation (SR) in 3-700 eV region. Values of Φ(hν) were found to increase linearly for hν≥75 eV. For hν≤40 eV, values of Φ(hν) gave a wealth of structures and are not linear to hν. Because number of secondary electrons produced by radiation is thought to increase in proportional to the incident photon energy, it is natural to conclude that the radiation chemistry effect becomes dominant above 75 eV. On the other hand, values of Φ(hν) showed response due to resonance rather than linear dependence with hν, which implies that the photochemical effect is dominant below 40 eV

  2. Improved efficiency in organic light-emitting devices with tris-(8-hydroxyquinoline) aluminium doped 9,10-di(2-naphthyl) anthracene emission layer

    International Nuclear Information System (INIS)

    Organic light-emitting devices with tris-(8-hydroxyquinoline) aluminium (Alq3) doped 9,10-di(2-naphthyl) anthracene (ADN) as the emission layer (EML) have been fabricated. These devices exhibit efficient electroluminescence (EL) originated from the Alq3 as the mass ratio of Alq3 to ADN was varied from 1 to 50%. The devices with an optimal Alq3 mass ratio of 10 wt% showed a peak EL efficiency and an external quantum efficiency of 9.1 cd A-1 and 2.7% at a luminance of 1371 cd m-2, which is improved by a factor of 2.2 compared with 4.1 cd A-1 and 1.2% at a luminance of 3267 cd m-2 for conventional devices with the neat Alq3 as the EML.

  3. Oral artemisinin prevents and delays the development of 7,12-dimethylbenz[a]anthracene (DMBA)-induced breast cancer in the rat.

    Science.gov (United States)

    Lai, Henry; Singh, Narendra P

    2006-01-01

    Artemisinin, a compound isolated from the sweet wormwood Artemisia annua L., has previously been shown to have selective toxicity towards cancer cells in vitro. In the present experiment, we studied the potential of artemisinin to prevent breast cancer development in rats treated with a single oral dose (50mg/kg) of 7,12-dimethylbenz[a]anthracene (DMBA), known to induce multiple breast tumors. Starting from the day immediately after DMBA treatment, one group of rats was provided with a powdered rat-chow containing 0.02% artemisinin, whereas a control group was provided with plain powdered food. For 40 weeks, both groups of rats were monitored for breast tumors. Oral artemisinin significantly delayed (Pcancer development in the monitoring period. In addition, breast tumors in artemisinin-fed rats were significantly fewer (Pcancer-chemoprevention agent. PMID:16356830

  4. Anthracene/phenothiazine π-conjugated sensitizers for dye-sensitized solar cells using redox mediator in organic and water-based solvents.

    Science.gov (United States)

    Lin, Ryan Yeh-Yung; Chuang, Tzu-Man; Wu, Feng-Ling; Chen, Pei-Yu; Chu, Te-Chun; Ni, Jen-Shyang; Fan, Miao-Syuan; Lo, Yih-Hsing; Ho, Kuo-Chuan; Lin, Jiann T

    2015-01-01

    Metal-free dyes (MD1 to MD5) containing an anthracene/phenothiazine unit in the spacer have been synthesized. The conversion efficiency (7.13 %) of the dye-sensitized solar cell using MD3 as the sensitizer reached approximately 85 % of the N719-based standard cell (8.47 %). The cell efficiency (8.42 %) of MD3-based dye-sensitized solar cells (DSSCs) with addition of chenodeoxycholic acid is comparable with that of N719-based standard cell. The MD3 water-based DSSCs using a dual-TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl)/iodide electrolyte exhibited very promising cell performance of 4.96 % with an excellent Voc of 0.77 V.

  5. Entropy Variation in the Two-dimensional Phase Transition of Anthracene Adsorbed at the Hg Electrode/Ethylene Glycol Solution Interface

    Directory of Open Access Journals (Sweden)

    Claudio Fontanesi

    2010-03-01

    Full Text Available The adsorption of anthracene (C14H10, at the mercury electrode/ethylene glycol (EG solution interface, is characterized by a low and almost constant capacity (about 8 μF cm−2 region (capacitive “pit” or “plateau” in capacity vs. potential curves, upon selection of suitable values of temperature, bulk concentration and applied potential values. This result is rationalized assuming the occurrence of a 2D phase transition between two distinct adsorbed phases: (i a “disordered” phase, characterized by a flat “parallel” disposition of the aromatic moiety on the electrode surface (ii an “ordered” phase, characterized by a “perpendicular” disposition of the aromatic moiety on the electrode surface. The experimental evidence is rationalized by considering the chemical potential as an explicit function of the “electric field/adsorbed molecule” interaction. Such a modelistic approach enables the determination of the relevant standard entropy variation.

  6. Effect of permethrin, anthracene and mixture exposure on shell components, enzymatic activities and proteins status in the Mediterranean clam Venerupis decussata

    Energy Technology Data Exchange (ETDEWEB)

    Sellami, Badreddine, E-mail: sellamibadreddine@gmail.com [Laboratory of Environment Biomonitoring, Coastal Ecology Unit, Faculty of Sciences of Bizerta, University of Carthage, 7021 Zarzouna (Tunisia); Khazri, Abdelhafidh [Laboratory of Environment Biomonitoring, Coastal Ecology Unit, Faculty of Sciences of Bizerta, University of Carthage, 7021 Zarzouna (Tunisia); Mezni, Amine [Unit of Research 99/UR12-30, Department of Chemistry, Faculty of Sciences of Bizerte, 7021 Jarzouna (Tunisia); Louati, Héla; Dellali, Mohamed; Aissa, Patricia; Mahmoudi, Ezzeddine; Beyrem, Hamouda [Laboratory of Environment Biomonitoring, Coastal Ecology Unit, Faculty of Sciences of Bizerta, University of Carthage, 7021 Zarzouna (Tunisia); Sheehan, David, E-mail: d.sheehan@ucc.ie [Environmental Research Institute and Department of Biochemistry, University College Cork, Western Gateway Building, Western Road, Cork (Ireland)

    2015-01-15

    Highlights: • We assessed toxicity of anthracene, permethrin and their mixture on clams. • Tissue and stressor-dependent changes were observed in biochemical responses. • Permethrin induces phase transition from aragonite to calcite in shell structure. • Interactive effects were observed on digestive gland and gill biomarkers. • Both approaches give new vision to risk assessment of organic pollution. - Abstract: Anthracene (ANT) and permethrin (PER) are two of the more toxic compounds reaching the marine environment. This study aimed to determine the impact of these molecules on Venerupis decussata, an economically important species cultured on the Tunisian coast. Shell structure and its possible transformation upon exposure to the two contaminants were studied by X-ray diffraction and gravimetric analyses. Results revealed a phase transition in shell composition from aragonite to calcite after PER exposure, to a mixture of PER and ANT (Mix) but not for ANT alone. Catalase (CAT), superoxide dismutase (SOD) and glutathione transferase (GST) activities were determined in digestive gland and gills after exposure to ANT, PER and Mix to assess the impact of the contamination on the oxidative status of V. decussata. Enzyme activities increased in the digestive gland after PER treatment and in the gills after ANT treatment. PER exposure significantly reduced the levels of free thiols and increased levels of carbonylated proteins in the digestive gland, as compared to controls. In contrast, ANT exposure significantly reduced free thiols and increased the number of carbonylated proteins in the gills. Mix induced additive effects as measured by both enzymatic and proteomic approaches. The present study suggests that PER has a strong effect on shell structure; that PER and ANT exposure generate compound-dependent oxidative stress in the tissues of V. decussata and that a mixture of the two compounds has synergistic effects on biochemical response.

  7. Ameliorative effect of Ananus comosus peel on 7, 12 dimethylbenz(α)anthracene induced mammary carcinogenesis with reference to oxidative stresss

    Institute of Scientific and Technical Information of China (English)

    M Kalaiselvi; D Gomathi; G Ravikumar; K Devaki; C Uma

    2013-01-01

    Objective: To Ananus comosus (A. comosus), has demonstrated a wide variety of biological activities which make it a good plant source for the treatment of many oxidative stress mediated diseases. The present study was aimed to evaluate therapeutic potential by assaying the activities of oxidative stress parameters in 7, 12 dimethylbenz(α)anthracene induced breast cancer rats. Methods: Animals were divided into five groups of six animals. Group I served as control, group II induced mammary carcinogenesis by 7, 12 dimethylbenz(α)anthracene, group III and IV are treatment groups (plant extract 250 mg/kg body weight and standard drug 10 mg/kg body weight) and group V served as animals treated with plant extract alone. All the animals were sacrificed after 30 days treatment and breast tissues are used for the analysis of protein content, enzymic and non-enzymic antioxidants using standard protocols. Results: The oral administrations of ethanolic peel extract of A. comosus (250 mg/kg body weight) to breast cancer bearing rats for 30 days demonstrated a significant (P<0.05) increased in body weight, tissue weight, protein content, enzymatic and non enzymatic levels. The altered activities of lipid peroxidation and tumor weight in breast tissue of control and experimental cancer bearing rats were significantly (P<0.05) were reverted to near normal levels by the administration of ethanolic extract suggesting that the extract have quenching capacity against free radicals thereby exhibiting anticancer potential of A. comosus in breast cancer bearing rats. Conclusions: Thus, modulatory effects of A. comosus on attenuating the lipid peroxidation and upregulation of oxidative stress key enzymes like enzymatic and non-enzymatic antioxidants, protein content afford a pledge for widespread use for the treatment of breast cancer in the future.

  8. Vertical and adiabatic excitations in anthracene from quantum Monte Carlo: Constrained energy minimization for structural and electronic excited-state properties in the JAGP ansatz

    Energy Technology Data Exchange (ETDEWEB)

    Dupuy, Nicolas, E-mail: nicolas.dupuy@impmc.upmc.fr [Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Université Pierre et Marie Curie, case 115, 4 place Jussieu, 75252 Paris Cedex 05 (France); Bouaouli, Samira, E-mail: samira.bouaouli@lct.jussieu.fr [Laboratoire de Chimie Théorique, Université Pierre et Marie Curie, case 115, 4 place Jussieu, 75252 Paris Cedex 05 (France); Mauri, Francesco, E-mail: francesco.mauri@impmc.upmc.fr; Casula, Michele, E-mail: michele.casula@impmc.upmc.fr [CNRS and Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, Université Pierre et Marie Curie, case 115, 4 place Jussieu, 75252 Paris Cedex 05 (France); Sorella, Sandro, E-mail: sorella@sissa.it [International School for Advanced Studies (SISSA), Via Beirut 2-4, 34014 Trieste, Italy and INFM Democritos National Simulation Center, Trieste (Italy)

    2015-06-07

    We study the ionization energy, electron affinity, and the π → π{sup ∗} ({sup 1}L{sub a}) excitation energy of the anthracene molecule, by means of variational quantum Monte Carlo (QMC) methods based on a Jastrow correlated antisymmetrized geminal power (JAGP) wave function, developed on molecular orbitals (MOs). The MO-based JAGP ansatz allows one to rigorously treat electron transitions, such as the HOMO → LUMO one, which underlies the {sup 1}L{sub a} excited state. We present a QMC optimization scheme able to preserve the rank of the antisymmetrized geminal power matrix, thanks to a constrained minimization with projectors built upon symmetry selected MOs. We show that this approach leads to stable energy minimization and geometry relaxation of both ground and excited states, performed consistently within the correlated QMC framework. Geometry optimization of excited states is needed to make a reliable and direct comparison with experimental adiabatic excitation energies. This is particularly important in π-conjugated and polycyclic aromatic hydrocarbons, where there is a strong interplay between low-lying energy excitations and structural modifications, playing a functional role in many photochemical processes. Anthracene is an ideal benchmark to test these effects. Its geometry relaxation energies upon electron excitation are of up to 0.3 eV in the neutral {sup 1}L{sub a} excited state, while they are of the order of 0.1 eV in electron addition and removal processes. Significant modifications of the ground state bond length alternation are revealed in the QMC excited state geometry optimizations. Our QMC study yields benchmark results for both geometries and energies, with values below chemical accuracy if compared to experiments, once zero point energy effects are taken into account.

  9. Vertical and adiabatic excitations in anthracene from quantum Monte Carlo: Constrained energy minimization for structural and electronic excited-state properties in the JAGP ansatz

    Science.gov (United States)

    Dupuy, Nicolas; Bouaouli, Samira; Mauri, Francesco; Sorella, Sandro; Casula, Michele

    2015-06-01

    We study the ionization energy, electron affinity, and the π → π∗ (1La) excitation energy of the anthracene molecule, by means of variational quantum Monte Carlo (QMC) methods based on a Jastrow correlated antisymmetrized geminal power (JAGP) wave function, developed on molecular orbitals (MOs). The MO-based JAGP ansatz allows one to rigorously treat electron transitions, such as the HOMO → LUMO one, which underlies the 1La excited state. We present a QMC optimization scheme able to preserve the rank of the antisymmetrized geminal power matrix, thanks to a constrained minimization with projectors built upon symmetry selected MOs. We show that this approach leads to stable energy minimization and geometry relaxation of both ground and excited states, performed consistently within the correlated QMC framework. Geometry optimization of excited states is needed to make a reliable and direct comparison with experimental adiabatic excitation energies. This is particularly important in π-conjugated and polycyclic aromatic hydrocarbons, where there is a strong interplay between low-lying energy excitations and structural modifications, playing a functional role in many photochemical processes. Anthracene is an ideal benchmark to test these effects. Its geometry relaxation energies upon electron excitation are of up to 0.3 eV in the neutral 1La excited state, while they are of the order of 0.1 eV in electron addition and removal processes. Significant modifications of the ground state bond length alternation are revealed in the QMC excited state geometry optimizations. Our QMC study yields benchmark results for both geometries and energies, with values below chemical accuracy if compared to experiments, once zero point energy effects are taken into account.

  10. Exploring the interaction of mercury(II) by N(2)S(2) and NS(3) anthracene-containing macrocyclic ligands: photophysical, analytical, and structural studies.

    Science.gov (United States)

    Tamayo, Abel; Pedras, Bruno; Lodeiro, Carlos; Escriche, Lluis; Casabó, Jaume; Capelo, José Luis; Covelo, Berta; Kivekäs, Raikko; Sillanpää, Reijo

    2007-09-17

    The complexation properties toward Hg(II) of six macrocyclic ligands, 3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L1), 7-(9-anthracenylmethyl)-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L2), 7-(10-methyl-9-anthracenylmethyl)-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L3), 7,7'-[9,10-anthracenediylbis(methylene)]bis-3,11-dithia-7,17-diazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L4), 1,4,7-trithia-11-azacyclotetradecane (L5), and 11,-(anthracen-9-ylmethyl)-1,4,7-trithia-11-azacyclotetradecane (L6), were studied. The stoichiometries of the formed species were determined from absorption and fluorescence titrations. In these anthracene-containing macrocycles, a fluorescent quenching of the emission was found upon Hg(II) addition. The X-ray crystal structure of [HgCl2(L2)] x 1/2CH2Cl2 was determined. The asymmetric unit contains two independent [HgCl2(L2)] molecules and one dichloromethane molecule. Each Hg(II) ion is coordinated by the pyridine nitrogen, the two sulfur atoms of one L2 molecule, and two chloride ions. Analytical studies using solvent extraction separation of Hg(II) from aqueous solutions were performed to determine the Hg(II) extraction capability of ligands L1, L2, and L5.

  11. Effects of anthracene and UV-B radiation on larvae of Argopecten irradians%蒽和UV-B辐射增强对海湾扇贝早期发育的影响

    Institute of Scientific and Technical Information of China (English)

    谭海丽; 王玉堃; 唐学玺; 周斌; 王其翔; 王悠

    2013-01-01

    The effects of anthracene and UV-B radiation on the early stage embryos development of benthos, and the single and joint a-cute toxicological effects of anthracene and UV-B radiation on the trochophore and D larvae of Argopecten irradians under the controlled laboratory conditions were studied. The results showed that with the increase of time and the anthracenes concentration or the increase of days and radiation does, the liabilities of the trochophore and D larvae declined. With the combination of anthracene and UV-B radiation , the liabilities of trochophore and D larvae were lower than those in the single action. Compared to D larvae, the trochophore was more sensitive to anthracene and UV-B radiation.%为了探讨蒽和UV-B辐射对底栖生物早期发育的影响,在实验生态学的条件下,选择海湾扇贝(Argopecten irradians)担轮幼虫和D型幼虫作为受试生物进行单一和联合急性毒性试验.结果表明:在实验的蒽浓度和UV-B辐射剂量下,随着蒽浓度和作用时间的增加,海湾扇贝担轮幼虫和D型幼虫的存活率逐渐降低;随着UV-B辐射剂量和辐射天数的增加,海湾扇贝担轮幼虫和D型幼虫存活率下降;在蒽和UV-B辐射共同作用对担轮幼虫和D型幼虫处理时,其两个发育阶段的存活率较两者单独作用的存活率均低很多;担轮幼虫较D型幼虫对蒽和UV-B辐射更敏感.

  12. Effect of permethrin, anthracene and mixture exposure on shell components, enzymatic activities and proteins status in the Mediterranean clam Venerupis decussata.

    Science.gov (United States)

    Sellami, Badreddine; Khazri, Abdelhafidh; Mezni, Amine; Louati, Héla; Dellali, Mohamed; Aissa, Patricia; Mahmoudi, Ezzeddine; Beyrem, Hamouda; Sheehan, David

    2015-01-01

    Anthracene (ANT) and permethrin (PER) are two of the more toxic compounds reaching the marine environment. This study aimed to determine the impact of these molecules on Venerupis decussata, an economically important species cultured on the Tunisian coast. Shell structure and its possible transformation upon exposure to the two contaminants were studied by X-ray diffraction and gravimetric analyses. Results revealed a phase transition in shell composition from aragonite to calcite after PER exposure, to a mixture of PER and ANT (Mix) but not for ANT alone. Catalase (CAT), superoxide dismutase (SOD) and glutathione transferase (GST) activities were determined in digestive gland and gills after exposure to ANT, PER and Mix to assess the impact of the contamination on the oxidative status of V. decussata. Enzyme activities increased in the digestive gland after PER treatment and in the gills after ANT treatment. PER exposure significantly reduced the levels of free thiols and increased levels of carbonylated proteins in the digestive gland, as compared to controls. In contrast, ANT exposure significantly reduced free thiols and increased the number of carbonylated proteins in the gills. Mix induced additive effects as measured by both enzymatic and proteomic approaches. The present study suggests that PER has a strong effect on shell structure; that PER and ANT exposure generate compound-dependent oxidative stress in the tissues of V. decussata and that a mixture of the two compounds has synergistic effects on biochemical response. PMID:25461742

  13. The anharmonic quartic force field infrared spectra of five non-linear polycyclic aromatic hydrocarbons: Benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene.

    Science.gov (United States)

    Mackie, Cameron J; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Mattioda, Andrew L; Buma, Wybren Jan; Lee, Timothy J; Tielens, Alexander G G M

    2016-08-28

    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. In this paper, we continue this work by extending the study to include five non-linear PAHs (benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene), thereby allowing us to make a full assessment of how edge structure, symmetry, and size influence the effects of anharmonicities. The theoretical anharmonic spectra are compared to spectra obtained under matrix isolation low-temperature conditions, low-resolution, high-temperature gas-phase conditions, and high-resolution, low-temperature gas-phase conditions. Overall, excellent agreement is observed between the theoretical and experimental spectra although the experimental spectra show subtle but significant differences. PMID:27586928

  14. Modulation of lipid peroxidation and antioxidant status upon administration of 'Shemamruthaa' in 7,12-dimethylbenz[a]anthracene induced mammary carcinoma bearing rats

    Institute of Scientific and Technical Information of China (English)

    Ayyakkannu Purushothaman; Elumalai Nandhakumar; Panchanatham Sachdanandam

    2012-01-01

    Objective: To investigate the therapeutic efficacy of a Shemamruthaa (SM), (combination of Hibiscus rosasinensis (H. rosasinensis) flowers, fruits of Phyllanthus emblica (P. emblica) and pure honey in definite ratio), against lipid peroxidation (LPO) and antioxidant status in experimentally induced mammary carcinoma rats. Methods: Adult female Sprague-Dawley rats were used for the study and were divided into four groups. Group I control animals received standard pellet diet and water ad libitum. Group II rats were induced with 7,12-dimethyl benz[a]anthracene (DMBA) (25 mg in 1 mL olive oil) by gastric intubation, whereas another set of DMBA-induced rats were treated with SM (400 mg/kg body weight/d) in olive oil orally by gastric intubation for 14 d after 3 months of induction period (group III). Group IV rats served as SM-treated control animals. At the end of the experimental period, the rats were anaesthetised and sacrificed and used for biochemical measures and histology studies. Results: The LPO was increased and antioxidant levels were decreased in the serum, liver and mammary tissues of cancer-induced rats. The administration of SM drug significantly (P<0.05) decreased LPO and reversed the status of antioxidants to near normal level in cancer-bearing animals. Conclusions: The results obtained indicate the additive and synergistic action of constituents’ plants in the SM drug against oxidative damage and its protective role in DMBA induced mammary cancer.

  15. The anharmonic quartic force field infrared spectra of five non-linear polycyclic aromatic hydrocarbons: Benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene

    Science.gov (United States)

    Mackie, Cameron J.; Candian, Alessandra; Huang, Xinchuan; Maltseva, Elena; Petrignani, Annemieke; Oomens, Jos; Mattioda, Andrew L.; Buma, Wybren Jan; Lee, Timothy J.; Tielens, Alexander G. G. M.

    2016-08-01

    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. In this paper, we continue this work by extending the study to include five non-linear PAHs (benz[a]anthracene, chrysene, phenanthrene, pyrene, and triphenylene), thereby allowing us to make a full assessment of how edge structure, symmetry, and size influence the effects of anharmonicities. The theoretical anharmonic spectra are compared to spectra obtained under matrix isolation low-temperature conditions, low-resolution, high-temperature gas-phase conditions, and high-resolution, low-temperature gas-phase conditions. Overall, excellent agreement is observed between the theoretical and experimental spectra although the experimental spectra show subtle but significant differences.

  16. Quercetin attenuates the development of 7, 12-dimethyl benz (a) anthracene (DMBA) and croton oil-induced skin cancer in mice

    Institute of Scientific and Technical Information of China (English)

    Huma Ali; Savita Dixit

    2015-01-01

    To evaluate the chemopreventive potential of quercetin in an experimental skin carcinogenesis mouse model.Skin tumor was induced by topical application of 7,12-dimethyl Benz (a) anthracene (DMBA) and Croton oil in Swiss albino mouse.Quercetin was orally administered at a concentration of 200 mg/kg and 400 mg/kg body weight daily for 16 weeks in mouse to evaluate chemopreventive potential.Skin cancer was assessed by histopathological analysis.We found that quercetin reduced the tumor size and the cumulative number of papillomas.The mean latent period was significantly increased as compared to carcinogen treated controls.Quercetin significantly decreased the serum levds of glutamate oxalate transaminase,glutamate pyruvate transaminase,alkaline phosphatase and bilirubin.It significantly increased the levels of glutathione,superoxide dismutase and catalase.The elevated level of lipid peroxides in the control group was significantly inhibited by quercetin.Futhermore,DNA damage was significantly decreased in quercetin treated mice as compared to DMBA and croton oil treated mice.The results suggest that quercetin exerts chemopreventive effect on DMBA and croton oil induced skin cancer in mice by increasing antioxidant activities.

  17. Eu3+/Sm3+ hybrids based with 8-hydroxybenz[de]anthracen-7-one organically modified mesoporous silica SBA-15/16

    Science.gov (United States)

    Gu, Yan-Jing; Yan, Bing

    2015-12-01

    A series of organic-inorganic hybrid materials were prepared by linking lanthanide (Eu3+, Sm3+) complexes to mesoporous SBA-15/SBA-16 through 8-hydroxybenz[de]anthracen-7-one modified silane (HBA-Si) as linker. The physical characterizations of these hybrids revealed that they all have high surface area, uniformity in mesostructure. The luminescence properties of these covalently bonded materials (denoted as Ln(HBA-SBA-15)3phen and Ln(HBA-SBA-16)3phen) were compared with ternary complexes (Ln(HBA)3phen) (Ln = Eu, Sm). Eu(HBA-SBA-15(16))3phen hybrids display better thermal stability, whose luminescent lifetimes and quantum efficiencies were matchable with those of Eu(HBA)3phen complex in spite of its much lower effective condensation of Eu3+ species. In addition, the luminescent performance of functionalized SBA-15 hybrids was more favorable than that of functionalized SBA-16 hybrids, revealing that SBA-15 was a better host material for lanthanide complex than mesoporous silica SBA-16.

  18. Paternal selenium deficiency but not supplementation during preconception alters mammary gland development and 7,12-dimethylbenz[a]anthracene-induced mammary carcinogenesis in female rat offspring.

    Science.gov (United States)

    Guido, Luiza N; Fontelles, Camile C; Rosim, Mariana P; Pires, Vanessa C; Cozzolino, Silvia M F; Castro, Inar A; Bolaños-Jiménez, Francisco; Barbisan, Luis F; Ong, Thomas P

    2016-10-15

    Breast cancer is a global public health problem and accumulating evidence indicates early-life exposures as relevant factors in the disease risk determination. Recent studies have shown that paternal nutrition can influence offspring health including breast cancer risk. Selenium is a micronutrient with essential role in central aspects of embryogenesis, male fertility and cancer and that has been extensively studied as a chemopreventive agent in several breast cancer experimental models. Thus, we designed an animal study to evaluate whether paternal selenium deficiency or supplementation during preconception could affect the female offspring mammary gland development and breast cancer susceptibility. Male Sprague-Dawley rats were fed AIN93-G diet containing 0.15 ppm (control diet), 0.05 ppm (deficient diet) or 1 ppm (supplemented diet) of selenium for 9 weeks and mated with control female rats. Mammary carcinogenesis was induced with 7,12-dimethylbenz[a]anthracene (DMBA) in their female offspring. Paternal selenium deficiency increased the number of terminal end buds, epithelial elongation and cell proliferation in the mammary gland of the female rat offspring and these effects were associated with higher susceptibility to DMBA-induced mammary tumors (increased incidence and higher grade tumors). On the other hand, paternal selenium supplementation did not influence any of these parameters. These results highlight the importance of father's nutrition including selenium status as a relevant factor affecting daughter's breast cancer risk and paternal preconception as a potential developmental stage to start disease preventive strategies. PMID:27270969

  19. The mechanism of anthracene interaction with photosynthetic apparatus: A study using intact cells, thylakoid membranes and PS II complexes isolated from Chlamydomonas reinhardtii

    Energy Technology Data Exchange (ETDEWEB)

    Aksmann, Anna, E-mail: bioaak@ug.edu.pl [Department of Plant Physiology, University of Gdansk, Al. Marszalka Pilsudskiego 46, 81-378 Gdynia (Poland); Shutova, Tatiana; Samuelsson, Goeran [Umea Plant Science Centre, Department of Plant Physiology, Umea University, SE 90187 Umea (Sweden); Tukaj, Zbigniew [Department of Plant Physiology, University of Gdansk, Al. Marszalka Pilsudskiego 46, 81-378 Gdynia (Poland)

    2011-08-15

    Intact cells of Chlamydomonas reinhardtii as well as isolated thylakoid membranes and photosystem II complexes were used to examine a possible mechanism of anthracene (ANT) interaction with the photosynthetic apparatus. Since ANT concentrations above 1 mM were required to significantly inhibit the rate of oxygen evolution in PS II membrane fragments it may indicate that the toxicant did not directly interact with this photosystem. On the other hand, stimulation of oxygen uptake by ANT-treated thylakoids suggested that ANT could either act as an artificial electron acceptor in the photosynthetic electron transport chain or function as an uncoupler. Electron transfer from excited chlorophyll to ANT is impossible due to the very low reduction potential of ANT and therefore we propose that toxic concentrations of ANT increase the thylakoid membrane permeability and thereby function as an uncoupler, enhancing electron transport in vitro. Hence, its unspecific interference with photosynthetic membranes in vitro suggests that the inhibitory effect observed on intact cell photosynthesis is caused by uncoupling of phosphorylation.

  20. The mechanism of anthracene interaction with photosynthetic apparatus: A study using intact cells, thylakoid membranes and PS II complexes isolated from Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    Intact cells of Chlamydomonas reinhardtii as well as isolated thylakoid membranes and photosystem II complexes were used to examine a possible mechanism of anthracene (ANT) interaction with the photosynthetic apparatus. Since ANT concentrations above 1 mM were required to significantly inhibit the rate of oxygen evolution in PS II membrane fragments it may indicate that the toxicant did not directly interact with this photosystem. On the other hand, stimulation of oxygen uptake by ANT-treated thylakoids suggested that ANT could either act as an artificial electron acceptor in the photosynthetic electron transport chain or function as an uncoupler. Electron transfer from excited chlorophyll to ANT is impossible due to the very low reduction potential of ANT and therefore we propose that toxic concentrations of ANT increase the thylakoid membrane permeability and thereby function as an uncoupler, enhancing electron transport in vitro. Hence, its unspecific interference with photosynthetic membranes in vitro suggests that the inhibitory effect observed on intact cell photosynthesis is caused by uncoupling of phosphorylation.

  1. Combination between Taxol-Encapsulated Liposomes and Eruca sativa Seed Extract Suppresses Mammary Tumors in Female Rats Induced by 7,12 Dimethylbenz(α)anthracene.

    Science.gov (United States)

    Shaban, Nadia; Abdel-Rahman, Salah; Haggag, Amany; Awad, Doaa; Bassiouny, Ahmad; Talaat, Iman

    2016-01-01

    Taxol (paclitaxel) is a powerful anti-cancer drug widely used against several types of malignant tumors. Because Taxol may exert several side effects, a variety of formulations have been developed. One of these features liposomes, regarded as one of the most promising drug carriers, biocompatible and best able to reduce drug toxicity without changing efficacy against tumor cells. Eruca sativa seed extract (SE) is considered a promising natural product from cruciferous vegetables against breast cancer, increasing chemotherapeutic and eliminating harmful side effects. The effects of Taxol-encapsulated liposomes (T) alone and in combination between Eruca sativa seed extract on nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2) and B-cell lymphoma-2 (Bcl-2) gene expression levels were investigated in rat mammary gland carcinogenesis induced by 7,12 dimethylbenz(α) anthracene (DMBA) using qRT-PCR. The results showed that DMBA increased NF-κB, COX-2 and Bcl-2 gene expression levels and lipid peroxidation (LP), while decreasing glutathione-S-transferase (GST) and superoxide dismutase (SOD) activities and total antioxidant concentration (TAC) compared to the control group. T and T-SE treatment reduced NF-κB, COX-2 and Bcl-2 gene expression levels and LP. Hence, T and T-SE treatment appeared to reduce inflammation and cell proliferation, while increasing apoptosis, GST and SOD activities and TAC.

  2. DNA excision repair in human cells treated with ultraviolet radiation and 7,12-dimethylbenz[a]anthracene 5,6-oxide

    International Nuclear Information System (INIS)

    Excision repair was measured in normal human and xeroderma pigmentosum group C cells treated with 7,12-dimethylbenz[a]anthracene 5,6-oxide and with ultraviolet radiation by the techniques of unscheduled DNA synthesis, repair replication, a modification of bromodeoxyuridine photolysis employing the dye Hoechst 33258 and 365 nm radiation, and endonuclease-sensitive sites assay. Radioautography and repair replication showed that in normal cells the magnitude of repair after a saturation dose of the epoxide (approx. 10 μM) to be 0.1-0.2 that after a saturating ultraviolet dose (20 J/m2 at 254), though survival data showed that both doses gave nearly similar killings. Repair was of the long-patch type and repair kinetics after the epoxide treatment were similar to ultraviolet. After a combined treatment with both agents, unscheduled synthesis in normal cells was more than additive, although, considering the experimental errors, these data and those of repair replication are consistent with additivity. The epoxide did not inhibit loss of sites sensitive to the ultraviolet endonuclease. However, after a combined treatment to xeroderma pigmentosum cells there was appreciably less unscheduled synthesis than for the sum of both treatments and the epoxide inhibited the loss of nuclease-sensitive sites. (Auth.)

  3. Apoptosis induction by S-allylcysteine, a garlic constituent, during 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

    Science.gov (United States)

    Balasenthil, S; Rao, K S; Nagini, S

    2002-09-01

    The apoptosis-inducing capacity of S-allylcysteine (SAC), a water-soluble garlic constituent, during 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch (HBP) carcinogenesis was investigated in male Syrian hamsters using DNA fragmentation and the apoptosis-associated proteins, tissue transglutaminase (tTG) and Bcl-2. Hamsters were divided into four groups of six animals each. Animals in group 1 were painted with a 0.5% solution of DMBA in liquid paraffin on the right buccal pouches three times a week for 14 weeks. Group 2 animals painted with DMBA as in group 1, in addition received 200 mg kg(-1) body weight SAC orally on days alternate to DMBA application. Group 3 animals received SAC as in group 2. Group 4 animals received neither DMBA nor SAC and served as the control. The experiment was terminated at the end of 14 weeks. Administration of SAC (200 mg kg(-1) body weight) to animals painted with DMBA inhibited DMBA-induced HBP carcinogenesis as revealed by the absence of neoplasms, induction of tTG and inhibition of Bcl-2 expression. The results of the present study suggest that SAC may exert its chemopreventive effect by inducing apoptosis. PMID:12125104

  4. Red Mold Rice Mitigates Oral Carcinogenesis in 7,12-Dimethyl-1,2-Benz[a]anthracene-Induced Oral Carcinogenesis in Hamster

    Directory of Open Access Journals (Sweden)

    Ruei-Lan Tsai

    2011-01-01

    Full Text Available The prevalence of oral tumor has exponentially increased in recent years; however, the effective therapies or prevention strategies are not sufficient. Red mold rice is a traditional Chinese food, and several reports have demonstrated that red mold rice had an anti-tumor effect. However, the possible anti-tumor mechanisms of the red mold rice are unclear. In this study, we examined the anti-tumor effect of red mold rice on 7,12-dimethyl-1,2-benz[a]anthracene (DMBA-induced oral tumor in hamster. The ethanol extract of red mold rice (RMRE treatment significantly decreases the levels of DMBA-induced reactive oxygen species, nitro oxide and prostaglandin E2 than those of the lovastatin-treated group (P < .001. Moreover, RMRE decreases the formation of oral tumor induced by DMBA. Monacolin K, monascin, ankaflavin or other red mold rice metabolites had been reported to decrease inflammation and oxidative stress and exerted anti-tumor effects. Therefore, we evaluated the anti-inflammation and anti-oxidative stress effects of monacolin K, monascin, ankaflavin and citrinin in lipopolysaccharide-treated RAW264.7 cells. We found that RMRE reduced the LPS-induced nitrite levels in RAW264.7 cells better than monacolin K, monascin, ankaflavin or citrinin (P < .05.

  5. Photodynamic cytotoxicity of mammalian cells exposed to sunlight-simulating near ultraviolet light in the presence of the carcinogen 7, 12-dimethylbenz(a)anthracene

    International Nuclear Information System (INIS)

    The coal-derived carcinogen 7,12-dimethylbenz(a)anthracene (DMBA), added to cultures of V79 Chinese Hamster, C3H mouse 10T1/2, and human HeLa cells enhanced photolethality induced by the sunlight-simulating emission from Westinghouse Sun Lamps (approximately 290-400 nm) but only in the presence of 02. Treatment of cells with DMBA after irradiation was without lethal effect; the endoperoxide of DMBA was ineffective both before as well as after irradiation, and DMBA incubation before far-UV exposure (254 nm) was protective. Cells rendered photosensitive by incubation with DMBA rapidly lost their sensitivity (in 0C) if incubation in a DMBA-free solution containing serum, but maintained their sensitivity at least for several hours if a serum-free solution was used. Although DMBA enhanced light-induced killing of cells in all phases of the cycle, those undergoing DNA syntheses were preferentially sensitized. The data supported photodynamic lethality due to one or both of the following: (1) the reaction with DNA of either DMBA radicals followed by oxidation, or DMBA-produced single oxygen; or (2) the peroxidation of lysosomal membranes followed by the release of hydrolases including DNAses. As a model system of the combined effects of a fossil-fuel derived polycyclic aromatic hydrocarbon and sunlight, the results with DMBA + near-UV are discussed in the context of altered cell properties (e.g. neoplastic transformation) in sublethally affected cells. (author)

  6. Pro-apoptotic and anti-inflammatory potential of andrographolide during 7,12-dimethylbenz[a]anthracene induced hamster buccal pouch carcinogenesis

    Directory of Open Access Journals (Sweden)

    Karthikeyan Sekar

    2012-08-01

    Full Text Available Objective: Aim of the present study was to investigate the modulating effect of andrographolide on apoptotic and inflammatory markers during 7,12-dimethyl-benz[a]anthracene (DMBA induced hamster buccal pouch carcinogenesis. Methods: Oral tumors were developed in the buccal pouch of golden Syrian hamsters by painting with 0.5% DMBA in liquid paraffin three times a week for 14 weeks. The expression pattern of molecular markers were assayed using immunohistochemistry (p53, Bcl-2 and Bax, ELISA (COX-2 and real-time PCR (NFκB. Results: We noticed 100% tumor formation accompanied by deregulation in the apoptotic and inflammatory markers in the buccal mucosa of hamsters treated with DMBA alone. Oral administration of andrographolide at a dose of 50 mg/kg b.w to hamsters treated with DMBA, not only completely prevented the tumor formation but also modulated the status of above mentioned molecular markers in favor of inhibiting cell proliferation as evidenced by no tumor formation. Conclusion: The present study suggests that the anti-tumor effect of andrographolide could partly be attributed to its apoptotic and anti-inflammatory potential during DMBA-induced hamster buccal pouch carcinogenesis. [J Exp Integr Med 2012; 2(4: 313-319

  7. Antineoplastic effect of iodine and iodide in dimethylbenz[a]anthracene-induced mammary tumors: association between lactoperoxidase and estrogen-adduct production.

    Science.gov (United States)

    Soriano, Ofelia; Delgado, Guadalupe; Anguiano, Brenda; Petrosyan, Pavel; Molina-Servín, Edith D; Gonsebatt, Maria E; Aceves, Carmen

    2011-08-01

    Several groups, including ours, have reported that iodine exhibited antiproliferative and apoptotic effects in various cancer cells only if this element is supplemented as molecular iodine, or as iodide, to cells that are able to oxidize it with the enzyme thyroperoxidase. In this study, we analyzed the effect of various concentrations of iodine and/or iodide in the dimethylbenz[a]anthracene (DMBA) mammary cancer model in rats. The results show that 0.1% iodine or iodide increases the expression of peroxisome proliferator-activated receptor type γ (PPARγ), triggering caspase-mediated apoptosis pathways in damaged mammary tissue (DMBA-treated mammary gland) as well as in frank mammary tumors, but not in normal mammary gland. DMBA treatment induces the expression of lactoperoxidase, which participates in the antineoplastic effect of iodide and could be involved in the pro-neoplastic effect of estrogens, increasing the formation of DNA adducts. In conclusion, our results show that a supplement of 0.1% molecular iodine/potassium iodide (0.05/0.05%) exert antineoplastic effects, preventing estrogen-induced DNA adducts and inducing apoptosis through PPARγ/caspases in pre-cancer and cancerous cells. Since this iodine concentration does not modify the cytology (histology, apoptosis rate) or physiology (triiodothyronine and thyrotropin) of the thyroid gland, we propose that it be considered as an adjuvant treatment for premenopausal mammary cancer.

  8. Effects of 7,12-dimethylbenz[a]anthracene on immune function and mixed-function oxygenase activity in the European starling

    Energy Technology Data Exchange (ETDEWEB)

    Trust, K.A.; Hooper, M.J. (Clemson Univ., SC (United States). Inst. of Wildlife and Environmental Toxicology); Fairbrother, A. (Environmental Protection Agency, Corvallis, OR (United States). Environmental Research Lab.)

    1994-05-01

    Immune function and hepatic MFO activity were examined in adult and nestling starlings administered a synthetic PAH, 7,12-dimethylbenz[a]anthracene (DMBA). Methods used to examine the starling immune system included immunopathology, macrophage phagocytosis, lymphocyte blastogenesis to concanavalin A, and hemagglutination of sheep erythrocytes (SRBC). Concomitant investigations of MFO activity were conducted in starlings exposed to DMBA. Ethoxyresorufin O-dealkylase (EROD) and pentoxyresorufin O-depentylase (PROD) were used as indicators of hepatic MFO activity. Changes in MFO activity were compared to chemically altered immune responses following DMBA exposure. Subcutaneous exposure of adult starlings to 125 mg/kg DMBA resulted in suppression of lymphocyte blastogenesis and antibody production to SRBC. EROD and PROD activity were increased 2.8- and 3.4-fold, respectively. Lymphocyte blastogenesis was impaired in adult starlings orally exposed to 125 mg/kg DMBA. The immune system of nestling starlings exposed orally to 100 mg/kg DMBA was altered, as evidenced by decreased phagocytic ability of macrophages and inhibition of lymphocyte blastogenesis. Oral exposure to DMBA did not induce MFO activity in starlings of either age class. Effects of DMBA on immune function and MFO activity in starlings varied with the age of birds and route and length of chemical exposure.

  9. Biorremediação de um solo contaminado com antraceno sob diferentes condições físicas e químicas Bioremediation of a soil contaminated with anthracene under different chemical and physical conditions

    Directory of Open Access Journals (Sweden)

    Rodrigo Josemar Seminoti Jacques

    2010-02-01

    Full Text Available O antraceno e os demais hidrocarbonetos aromáticos policíclicos (HAPs podem ser removidos do solo pela biorremediação, cuja eficiência é limitada se as condições físicas e químicas não forem favoráveis à sobrevivência e à atividade dos microrganismos degradadores. O objetivo do presente estudo foi avaliar a influência do pH, da umidade e da disponibilidade de nitrogênio, de fósforo, de ferro e de enxofre na biorremediação de um solo contaminado com antraceno. Para tanto, amostras de um solo arenoso foram contaminadas em laboratório com 500mg kg-1 de antraceno e a mineralização desse poluente foi quantificada por respirometria. As maiores mineralizações ocorreram nos tratamentos com as maiores umidades e os pH avaliados. A adição de 100kg ha-1 ou mais de nitrogênio no solo e a redução da relação C HAP-N para valores inferiores a 120:17 diminuíram a mineralização do antraceno. O aumento da disponibilidade do fósforo, do ferro e do enxofre e a presença de amplas relações C HAP:P no solo não influenciaram a mineralização do antraceno. A correção do pH e o adequado fornecimento de água possibilitaram a biorremediação desse solo em curto período de tempo.The anthracene, as well as the others polycyclic aromatic hydrocarbons (PAH, can be removed from the soil by bioremediation, whose efficiency is limited under unfavorable physical and chemical conditions to the survival and activity of the microbial degraders. The objective of this study was to evaluate the influence of pH, water content, and nitrogen, phosphorus, iron and sulfur concentrations in the bioremediation of a soil contaminated with anthracene. Samples of a sandy soil were contaminated in laboratory with anthracene (500mg kg-1 and the mineralization was evaluated by respirometry. The highest anthracene mineralization was verified in the soil with the highest water content and pH value studied. The addition of 100kg ha-1 nitrogen in the soil

  10. Isolation of an Anthracene-Degrading Strain Aspergillus fumigatus A10 and Its Degradation Characteristics%蒽降解菌烟曲霉A10的分离及降解性能研究

    Institute of Scientific and Technical Information of China (English)

    强婧; 尹华; 彭辉; 叶锦韶; 秦华明; 何宝燕; 张娜

    2009-01-01

    从污染环境中筛选出1株蒽降解菌A10,经鉴定为烟曲霉(Aspergillus fumigatus),其对蒽的降解率随时间的延长逐渐升高,在12~84 h,蒽降解率增长速率较快;此后降解率的增加趋于平缓,最终(168 h)能够达到83%左右.当无机盐培养液中蒽初始浓度为10 mg/L,A10投菌量为50 g/L(以湿重计),菌龄为36 h时, 5 d内蒽降解率为79.37%.蒽浓度对菌发挥降解作用有较大影响,浓度为5 mg/L时,降解率最高,达92.17%.培养液初始pH为5.0~7.5时,降解率维持在60%左右;温度为30℃、氧气量为4.30 mg/L时蒽降解效果较好.一定量的营养盐的添加能在一定程度上促进蒽的降解.共代谢底物乳糖的添加,能使蒽的降解率提高37.15%.对蒽降解过程的初步研究表明,菌株A10对蒽的降解是一个胞外吸附/胞内降解的动态变化过程.红外光谱分析显示,在微生物作用下,蒽的结构发生改变,生成了含有1~2个苯环的芳香酸、芳香酮、芳香醛和饱和碳氢化合物等一系列降解产物.%An anthracene-degrading strain (A10) was isolated from contaminated environment and identified as Aspergillus fumigatus.The experimental results showed that the biodegradation rate of anthracene increased with the increasing time.Between 12-84 h interval, the biodegradation performed rapidly, while after this, the increase of biodegradation rate tended to become slow, and ultimately the biodegradation rate could achieve approximately 83%.The degradation rate of anthracene reached 79.37% within 5 days when the initial concentration of anthracene in mineral salts medium (MSM) was 10 mg/L, the inoculum dosage was 50 g/L (wet weight) and the cell age was 36 h.The concentration of anthracene had notable influence on degradation function of strain A10 and the highest degradation rate (92.17%) was achieved when anthracene concentration was 5 mg/L.The degradation rate could maintain about 60% with initial pH of MSM in the range of 5

  11. Theoretical study on exciton recurrence motion in anthracene dimer using the Ab initio MO-CI based quantum master equation approach.

    Science.gov (United States)

    Kishi, Ryohei; Nakano, Masayoshi; Minami, Takuya; Fukui, Hitoshi; Nagai, Hiroshi; Yoneda, Kyohei; Takahashi, Hideaki

    2009-05-01

    We apply the ab initio molecular orbital (MO)-configuration interaction (CI) based quantum master equation (MOQME) method to the investigation of ultrafast exciton dynamics in an anthracene dimer modeled after anthracenophane, which is experimentally found to exhibit an oscillatory signal of fluorescence anisotropy decay. Two low-lying near-degenerate one-photon allowed excited states with a slight energy difference (42 cm(-1)) are obtained at the CIS/6-31G** level of approximation using full valence pi-orbitals. The time evolution of reduced exciton density matrices is performed by numerically solving the quantum master equation. After the creation of a superposition state of these near-degenerate states by irradiating a near-resonant laser field, we observe two kinds of oscillatory behaviors of polarizations: field-induced polarizations with faster periods, and amplitude oscillations of x- and z-polarizations, P(x) and P(z), with a slower period, in which the amplitudes of P(x) and P(z) attain maximum alternately. The latter behavior turns out to be associated with an oscillatory exciton motion between the two monomers, i.e., exciton recurrence motion, using the dynamic exciton expression based on the polarization density. From the analysis of contribution to the exciton distributions, such exciton recurrence motion is found to be characterized by both the difference in eigenfrequencies between the two near-degenerate states excited by the laser field and the relative phases among the frontier MOs primarily contributing to the near-degenerate states.

  12. Embryotoxic effects of benzo[a]pyrene, chrysene and 7,12-dimethylbenz[a]-anthracene in petroleum hydrocarbon mixtures in mallard ducks

    Science.gov (United States)

    Hoffman, D.J.; Gay, M.L.

    1981-01-01

    Studies with different avian species have revealed that surface applications of microliter amounts of some crude and fuel oils that coat less than 70% of the egg surface result in considerable reduction in hatching with teratogenicity and stunted growth. Other stUdies have shown that the embryo toxicity is dependent on the aromatic hydrocarbon content, further suggesting that the toxicity is due to causes other than asphyxia. In the present study the effects of three polycyclic aromatic hydrocarbons identified in petroleum were examined on mallard (Anas platyrhynchos) embryo development. Addition of benzo[a]pyrene (BaP), chrysene, or 7,7 2-dimethylbenz[ a]anthracene (DMBA) to a synthetic petroleum hydrocarbon mixture of known composition and relatively low embryotoxicity resulted in embryo toxicity that was enhanced or equal to that of crude oil when 10 :I was applied externally to eggs at 72 h of development. The order of ability to enhance embryo toxicity was DMBA > BaP > chrysene. The temporal pattern of embryonic death was similar to that reported after exposure to crude oil, with additional mortality occurring after outgrowth of the chorioallantois. Retarded growth, as reflected by embryonic body weight, crown-rump length, and bill length, was accompanied by teratogenicity. Abnormal embryos exhibited extreme stunting; eye, brain, and bill defects; and incomplete ossification. Gas chromatographic-mass spectral analysis of externally treated eggs showed the passage of aromatic hydrocarbons including chrysene through the shell and shell membranes to the developing embryos. These findings suggest that the presence of polycyclic aromatic hydrocarbons in petroleum, including BaP, chrysene, and DMBA, significantly enhances the overall embryotoxicity in avian species.

  13. Anticancer and antimutagenic properties of Acacia nilotica (Linn.) on 7,12-dimethylbenz(a)anthracene-induced skin papillomagenesis in Swiss albino mice.

    Science.gov (United States)

    Meena, Punar Dutt; Kaushik, Pallavi; Shukla, Shalini; Soni, Anil Kumar; Kumar, Manish; Kumar, Ashok

    2006-01-01

    We report the chemopreventive activity of Acacia nilotica (Linn.) gum, flower and leaf aqueous extracts, on 7,12-dimethylbenz(a)anthracene (DMBA) induced skin papillomagenesis in male Swiss albino mice. Animals were divided into following groups: Group I (Controls) given DMBA and croton oil, with no extract ; Group II (treatment) animals treated with Acacia nilotica gum (Group II-a) (800 mg/kg body weight), flowers (Group II-b) (800 mg/kg body weight), or leaves (Group II-c) (800 mg/kg body weight) during the peri- and post initiation periods of DMBA and croton oil application. A significant reduction in the values of tumor burden, tumor incidence and cumulative number of papillomas was observed in mice treated by oral gavage with the Acacia nilotica gum, flower and leaf extracts as compared with the control group. The latency period in treatment Group-II (b) and Group-II (c) was significantly increased as compared with the control group. A significant reduction in the frequency of micronuclei was also observed in mice treated by oral gavage with the aqueous extracts, along with significant decrease in total chromosomal aberrations in the form of chromatid breaks, chromosome breaks, centric rings, dicentrics, acentric fragments and exchange. Treatment with Acacia nilotica flower (Group II-B) and leaf (Group II-C) aqueous extracts by oral gavage for 15 days resulted in a highly significant decrease in the lipid peroxidation (LPO) level in the liver, but this was less evident with the gum (Group II-A) . Conversely, reduced glutathione (GSH) content was observed to be significantly elevated as compared with the control group with leaves (Group II-C) and flowers (Group II-B). The chemopreventive and antimutagenic activity of the leaf extract of Acacia nilotica was most significant followed by the flower extract and then by gum. PMID:17250441

  14. Impact of obesity on 7,12-dimethylbenz[a]anthracene-induced altered ovarian connexin gap junction proteins in female mice

    International Nuclear Information System (INIS)

    The ovarian gap junction proteins alpha 4 (GJA4 or connexin 37; CX37), alpha 1 (GJA1 or connexin 43; CX43) and gamma 1 (GJC1 or connexin 45; CX45) are involved in cell communication and folliculogenesis. 7,12-dimethylbenz[a]anthracene (DMBA) alters Cx37 and Cx43 expression in cultured neonatal rat ovaries. Additionally, obesity has an additive effect on DMBA-induced ovarian cell death and follicle depletion, thus, we investigated in vivo impacts of obesity and DMBA on CX protein levels. Ovaries were collected from lean and obese mice aged 6, 12, 18, or 24 wks. A subset of 18 wk old mice (lean and obese) were dosed with sesame oil or DMBA (1 mg/kg; ip) for 14 days and ovaries collected 3 days thereafter. Cx43 and Cx45 mRNA and protein levels decreased (P < 0.05) after 18 wks while Cx37 mRNA and protein levels decreased (P < 0.05) after 24 wks in obese ovaries. Cx37 mRNA and antral follicle protein staining intensity were reduced (P < 0.05) by obesity while total CX37 protein was reduced (P < 0.05) in DMBA exposed obese ovaries. Cx43 mRNA and total protein levels were decreased (P < 0.05) by DMBA in both lean and obese ovaries while basal protein staining intensity was reduced (P < 0.05) in obese controls. Cx45 mRNA, total protein and protein staining intensity level were decreased (P < 0.05) by obesity. These data support that obesity temporally alters gap junction protein expression and that DMBA-induced ovotoxicity may involve reduced gap junction protein function. - Highlights: • Ovarian gap junction proteins are affected by ovarian aging and obesity. • DMBA exposure negatively impacts gap junction proteins. • Altered gap junction proteins may contribute to infertility

  15. Impact of obesity on 7,12-dimethylbenz[a]anthracene-induced altered ovarian connexin gap junction proteins in female mice

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Nteeba, Jackson, E-mail: nteeba@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2015-01-01

    The ovarian gap junction proteins alpha 4 (GJA4 or connexin 37; CX37), alpha 1 (GJA1 or connexin 43; CX43) and gamma 1 (GJC1 or connexin 45; CX45) are involved in cell communication and folliculogenesis. 7,12-dimethylbenz[a]anthracene (DMBA) alters Cx37 and Cx43 expression in cultured neonatal rat ovaries. Additionally, obesity has an additive effect on DMBA-induced ovarian cell death and follicle depletion, thus, we investigated in vivo impacts of obesity and DMBA on CX protein levels. Ovaries were collected from lean and obese mice aged 6, 12, 18, or 24 wks. A subset of 18 wk old mice (lean and obese) were dosed with sesame oil or DMBA (1 mg/kg; ip) for 14 days and ovaries collected 3 days thereafter. Cx43 and Cx45 mRNA and protein levels decreased (P < 0.05) after 18 wks while Cx37 mRNA and protein levels decreased (P < 0.05) after 24 wks in obese ovaries. Cx37 mRNA and antral follicle protein staining intensity were reduced (P < 0.05) by obesity while total CX37 protein was reduced (P < 0.05) in DMBA exposed obese ovaries. Cx43 mRNA and total protein levels were decreased (P < 0.05) by DMBA in both lean and obese ovaries while basal protein staining intensity was reduced (P < 0.05) in obese controls. Cx45 mRNA, total protein and protein staining intensity level were decreased (P < 0.05) by obesity. These data support that obesity temporally alters gap junction protein expression and that DMBA-induced ovotoxicity may involve reduced gap junction protein function. - Highlights: • Ovarian gap junction proteins are affected by ovarian aging and obesity. • DMBA exposure negatively impacts gap junction proteins. • Altered gap junction proteins may contribute to infertility.

  16. Hepatic dysfunction induced by 7, 12-dimethylbenz(αanthracene and its obviation with erucin using enzymatic and histological changes as indicators.

    Directory of Open Access Journals (Sweden)

    Rohit Arora

    Full Text Available The toxicity induced by 7, 12-dimethylbenz(αanthracene (DMBA has been widely delineated by a number of researchers. This potent chemical damages many internal organs including liver, by inducing the production of reactive oxygen species, DNA-adduct formation and affecting the activities of phase I, II, antioxidant and serum enzymes. Glucosinolate hydrolytic products like isothiocyanates (ITCs are well known for inhibiting the DNA-adduct formation and modulating phase I, II enzymes. Sulforaphane is ITC, currently under phase trials, is readily metabolized and inter-converted into erucin upon ingestion. We isolated erucin from Eruca sativa (Mill. Thell. evaluated its hepatoprotective role in DMBA induced toxicity in male wistar rats. The rats were subjected to hepatic damage by five day regular intraperitoneal doses of DMBA. At the end of the protocol, the rats were euthanized, their blood was collected and livers were processed. The liver homogenate was analyzed for phase I (NADPH-cytochrome P450 reductase, NADH-cytochrome b5 reductase, cytochrome P450, cytochrome P420 and cytochrome b5, phase II (DT diaphorase, glutathione-S-transferase and γ-glutamyl transpeptidase and antioxidant enzymes (superoxide dismutase, catalase, guaiacol peroxidise, ascorbate peroxidise, glutathione reductase and lactate dehydrogenase. The level of thiobarbituric acid reactive substances, lipid hydroperoxides, conjugated dienes and reduced glutathione in the liver homogenate was also analyzed. The serum was also analyzed for markers indicating hepatic damage (alkaline phosphatase, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, direct bilirubin and total bilirubin. Erucin provided significant protection against DMBA induced damage by modulating the phase I, II and antioxidant enzymes. The histological evaluation of liver tissue was also conducted, which showed the hepatoprotective role of erucin.

  17. Hepatic Dysfunction Induced by 7, 12-Dimethylbenz(α)anthracene and Its Obviation with Erucin Using Enzymatic and Histological Changes as Indicators

    Science.gov (United States)

    Arora, Rohit; Bhushan, Sakshi; Kumar, Rakesh; Mannan, Rahul; Kaur, Pardeep; Singh, Amrit Pal; Singh, Bikram; Vig, Adarsh P.; Sharma, Deepika; Arora, Saroj

    2014-01-01

    The toxicity induced by 7, 12-dimethylbenz(α)anthracene (DMBA) has been widely delineated by a number of researchers. This potent chemical damages many internal organs including liver, by inducing the production of reactive oxygen species, DNA-adduct formation and affecting the activities of phase I, II, antioxidant and serum enzymes. Glucosinolate hydrolytic products like isothiocyanates (ITCs) are well known for inhibiting the DNA-adduct formation and modulating phase I, II enzymes. Sulforaphane is ITC, currently under phase trials, is readily metabolized and inter-converted into erucin upon ingestion. We isolated erucin from Eruca sativa (Mill.) Thell. evaluated its hepatoprotective role in DMBA induced toxicity in male wistar rats. The rats were subjected to hepatic damage by five day regular intraperitoneal doses of DMBA. At the end of the protocol, the rats were euthanized, their blood was collected and livers were processed. The liver homogenate was analyzed for phase I (NADPH-cytochrome P450 reductase, NADH-cytochrome b5 reductase, cytochrome P450, cytochrome P420 and cytochrome b5), phase II (DT diaphorase, glutathione-S-transferase and γ-glutamyl transpeptidase) and antioxidant enzymes (superoxide dismutase, catalase, guaiacol peroxidise, ascorbate peroxidise, glutathione reductase and lactate dehydrogenase). The level of thiobarbituric acid reactive substances, lipid hydroperoxides, conjugated dienes and reduced glutathione in the liver homogenate was also analyzed. The serum was also analyzed for markers indicating hepatic damage (alkaline phosphatase, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, direct bilirubin and total bilirubin). Erucin provided significant protection against DMBA induced damage by modulating the phase I, II and antioxidant enzymes. The histological evaluation of liver tissue was also conducted, which showed the hepatoprotective role of erucin. PMID:25390337

  18. Hepatic dysfunction induced by 7, 12-dimethylbenz(α)anthracene and its obviation with erucin using enzymatic and histological changes as indicators.

    Science.gov (United States)

    Arora, Rohit; Bhushan, Sakshi; Kumar, Rakesh; Mannan, Rahul; Kaur, Pardeep; Singh, Amrit Pal; Singh, Bikram; Vig, Adarsh P; Sharma, Deepika; Arora, Saroj

    2014-01-01

    The toxicity induced by 7, 12-dimethylbenz(α)anthracene (DMBA) has been widely delineated by a number of researchers. This potent chemical damages many internal organs including liver, by inducing the production of reactive oxygen species, DNA-adduct formation and affecting the activities of phase I, II, antioxidant and serum enzymes. Glucosinolate hydrolytic products like isothiocyanates (ITCs) are well known for inhibiting the DNA-adduct formation and modulating phase I, II enzymes. Sulforaphane is ITC, currently under phase trials, is readily metabolized and inter-converted into erucin upon ingestion. We isolated erucin from Eruca sativa (Mill.) Thell. evaluated its hepatoprotective role in DMBA induced toxicity in male wistar rats. The rats were subjected to hepatic damage by five day regular intraperitoneal doses of DMBA. At the end of the protocol, the rats were euthanized, their blood was collected and livers were processed. The liver homogenate was analyzed for phase I (NADPH-cytochrome P450 reductase, NADH-cytochrome b5 reductase, cytochrome P450, cytochrome P420 and cytochrome b5), phase II (DT diaphorase, glutathione-S-transferase and γ-glutamyl transpeptidase) and antioxidant enzymes (superoxide dismutase, catalase, guaiacol peroxidise, ascorbate peroxidise, glutathione reductase and lactate dehydrogenase). The level of thiobarbituric acid reactive substances, lipid hydroperoxides, conjugated dienes and reduced glutathione in the liver homogenate was also analyzed. The serum was also analyzed for markers indicating hepatic damage (alkaline phosphatase, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, direct bilirubin and total bilirubin). Erucin provided significant protection against DMBA induced damage by modulating the phase I, II and antioxidant enzymes. The histological evaluation of liver tissue was also conducted, which showed the hepatoprotective role of erucin.

  19. 9D nonadiabatic quantum dynamics through a four-state conical intersection: Investigating the homolysis of the O-O bond in anthracene-9,10-endoperoxide

    Science.gov (United States)

    Assmann, Mariana; Worth, Graham A.; González, Leticia

    2012-12-01

    The excited state dynamics of anthracene-9,10-endoperoxide is investigated using quantum wavepacket dynamics. APO is an aromatic endoperoxide which, upon excitation to S1, shows a cleavage of the oxygen-oxygen bond, leading to rearrangement products. It was shown that the dynamics of the O-O cleavage is modulated by a four-state degeneracy [D. Mollenhauer, I. Corral, and L. González, J. Phys. Chem. Lett. 1, 1036 (2010)], 10.1021/jz100196q. The most important mode to describe the O-O cleavage is the opening of the O-O bond. Excitation to higher excited states Sn (n ⩾ 2) leads to the release of singlet molecular oxygen. For this release, the twist of the oxygen atoms around the molecular axis is an important mode. These two degrees of freedom were employed to calculate two-dimensional potential energy surfaces for the four singlet states which become degenerate. Further modes were included in terms of harmonic oscillators. Using the multiconfigurational time-dependent Hartree method, quantum dynamic simulations were performed in up to nine degrees of freedom. Moreover, the nine branching space vectors, which prove the degeneracy to be a four-state conical intersection (4CI), were calculated and included in the wavepacket propagations. The resulting dynamics show that the 4CI is reached very fast (in less than 30 fs after excitation) and the wavepacket distributes over all states. The degree of distribution into the states is very much dependent on which modes are included in the simulation.

  20. Controlled release low dose medroxyprogesterone acetate (MPA) inhibits the development of mammary tumors induced by dimethyl-benz(a) anthracene in the rat.

    Science.gov (United States)

    Labrie, F; Li, S; Bélanger, A; Côté, J; Mérand, Y; Lepage, M

    1993-01-01

    Medroxyprogesterone acetate (MPA) is well recognized to have beneficial effects for the treatment of advanced breast cancer which are comparable to those achieved with other forms of endocrine therapy. Using mammary tumors induced in the rat by dimethylbenz(a)anthracene (DMBA) as a model, we have studied the possibility that low dose MPA could prevent the development of these tumors. Single subcutaneous injection of Depo-Provera (crystalline suspension of MPA) or MPA encapsulated in biodegradable microspheres of 50:50 poly[DL-lactide-co-glycolide] was given 7 days before oral DMBA. While 63% of intact animals developed palpable mammary tumors within 85 days after DMBA administration, tumor incidence decreased to 28% and 23% in animals who had received 30 mg and 100 mg of Depo-Provera, respectively. The same amounts of MPA delivered in microspheres caused a further decrease in tumor incidence to respective values of 7% and 6%. Average tumor area, on the other hand, decreased from 4.89 cm2 in intact rats to about 0.75 (0.57-0.88) cm2 and approximately 0.20 (0.14-0.22) cm2 in the Depo-Provera and microsphere-treated groups, respectively. Using the 50:50 formulation of poly[DL-lactide-co-glycolide] designed to release MPA at a constant rate for a 4-month period, the serum MPA concentration at 3 months was measured at 4.99 +/- 0.43 ng/ml. Such data suggest that administration of a low dose controlled-release formulation of MPA in 50:50 poly[DL-lactide-co-glycolide] microspheres could well be an efficient and well tolerated approach for the prevention of breast cancer in women. PMID:8251650

  1. Proteomic analysis of the murine liver in response to a combined exposure to psychological stress and 7,12-dimethylbenz(a)anthracene.

    Science.gov (United States)

    Flint, Melanie S; Hood, Brian L; Sun, Mai; Stewart, Nicolas A; Jones-Laughner, Jacqueline; Conrads, Thomas P

    2010-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are environmental carcinogens implicated to underlie development of several types of cancers. Cytochrome P450 (CYP) enzymes play key roles in the conversion of PAHs to highly potent carcinogens, namely diol epoxides. 7,12-Dimethylbenz(a)anthracene (DMBA), a PAH, is highly carcinogenic, where in mouse models it is known to be responsible for initiating tumor formation in many organs including mammary tissues, ovaries, and skin. Psychological stress, via release of biochemical mediators, can greatly impact carcinogenesis. The present investigation examined the hypothesis that psychological stress modulates metabolism and carcinogenicity of DMBA through alteration of key drug metabolizing enzyme abundance levels in the liver utilizing mass spectrometry-based proteomics. To test this hypothesis, four groups of mice were treated as follows: nonstressed, stressed, nonstressed/DMBA-exposed, and stressed/DMBA-exposed, where the stressor was a well-accepted model of restraint. Liver proteins were extracted, resolved by one-dimensional gel electrophoresis, digested in-gel with trypsin, and analyzed by liquid chromatography-tandem mass spectrometry. This investigation resulted in the unique identification of 59 isoforms of CYP enzymes. Changes in protein abundances derived from spectral counting indicates that stress alone results in increases in the abundance of proteins responsive to oxidative stress, along with Phase I and II metabolizing enzymes, such as CYP2J5 and UDP glucoronytransferases. The proteomic results further indicate that exposure to DMBA induces increases in the abundance of CYP1A2 and serine protease inhibitors and decreases the abundance of CYP4 V3. Finally, significant changes in the abundance of proteins such as CYP1A2, CYP3A11, and Topoisomerase-2 were found between nonstressed and stressed/DMBA-treated mice. These data support the hypothesis that psychological stress modulates DMBA-induced regulation of drug

  2. Daphnetin ameliorates 7,12-dimethylbenz[a]anthracene-induced mammary carcinogenesis through Nrf-2-Keap1 and NF-κB pathways.

    Science.gov (United States)

    Kumar, Abhishek; Jha, S; Pattanayak, Shakti P

    2016-08-01

    Cancer is a faction of disorders that conjugated primarily with oxidative imbalance. In mammary carcinoma, oxidative stress secondarily changes various gene expressions and signalling pathways that bring genomic instability and mutagenic alterations that fascinating carcinogenesis. Several coumarin compounds are active against various malignancies. Among them, daphnetin (DAP) exhibits valuable safety and bioactivity profile that contributes towards its efficacy against cancer. In this study, the antioxidative and chemotherapeutic potential of DAP against 7,12-dimethylbenz(a)anthracene (DMBA)- induced mammary carcinogenesis was evaluated in female Sprague-Dawley rats. Besides this, we have determined the effect of DAP on Keap1-Nrf-2, associated HO-1 and NF-κB expressions behind the antioxidative and anti-proliferating activity. In our findings, a protective effect of DAP was established against lipid peroxidation, enzymic (Total SOD, MnSOD, CuZnSOD, CAT, GPx) and non-enzymic (GSH) antioxidative markers in serum, liver, kidney and breast tissue of both control and experimental groups. An up-regulation of protective Nrf-2 & HO-1 with a synchronized suppression in Keap1 & NF-κB mRNA and protein expressions were observed. DAP revealed the inhibition of p-AKT which accountable for decrease in NF-κB expressions but shown to be ineffective on p-ERK1/2. This study revealed that DAP inhibits mammary carcinogenesis through multiple mechanisms. Dual efficacy of DAP on Nrf-2-Keap1 pathway and NF-κB expressions propose it as a potential chemotherapeutic agent in mammary cancer management. PMID:27470383

  3. (E-3-(Anthracen-9-yl-1-(furan-2-ylprop-2-en-1-oneThis paper is dedicated to His Majesty King Bhumibol Adulyadej of Thailand (King Rama IX for his sustainable development of the country.

    Directory of Open Access Journals (Sweden)

    Jirapa Horkaew

    2010-04-01

    Full Text Available In the molecule of the title heteroaryl chalcone derivative, C21H14O2, the almost planar prop-2-en-1-one unit [r.m.s. deviation = 0.0087 (1 Å] forms dihedral angles of 5.81 (7 and 49.85 (6°, respectively, with the furan ring and anthracene ring system. In the crystal structure, the molecules are linked into a two-dimensional network parallel to (100 by C—H...O hydrogen bonds and π...π interactions involving the furan rings [centroid–centroid distance = 3.7205 (6 Å].

  4. 7,12-Dimethylbenz(a)anthracene-induced genotoxicity on bone marrow cells from mice phenotypically selected for low acute inflammatory response.

    Science.gov (United States)

    Katz, Iana Suly Santos; Albuquerque, Layra Lucy; Suppa, Alessandra Paes; da Silva, Graziela Batista; Jensen, José Ricardo; Borrego, Andrea; Massa, Solange; Starobinas, Nancy; Cabrera, Wafa Hanna Koury; De Franco, Marcelo; Borelli, Primavera; Ibañez, Olga Martinez; Ribeiro, Orlando Garcia

    2016-01-01

    Exposure to polycyclic aromatic hydrocarbon (PAH) environmental contaminants has been associated with the development of mutations and cancer. 7,12-Dimethylbenz(a)anthracene ( DMBA), a genotoxic agent, reacts with DNA directly, inducing p53-dependent cytotoxicity resulting in cell death by apoptosis or giving rise to cancer. DMBA metabolism largely depends on activation of the aryl hydrocarbon receptor (AhR). Mice phenotypically selected for high (AIRmax) or low (AIRmin) acute inflammatory response present a complete segregation of Ahr alleles endowed with low (Ahr(d)) or high (Ahr(b1)) affinity to PAHs, respectively. To evaluate the role of AhR genetic polymorphism on the bone marrow susceptibility to DMBA, AIRmax and AIRmin mice were treated with a single intraperitoneal injection of DMBA (50mg/kg b.w.) in olive oil. Bone marrow cells (BMCs) were phenotyped by both flow cytometry and cytoslide preparations. Despite a significant decrease in total cell count in BM from AIRmin mice, there was an increase of blast cells and immature neutrophils at 1 and 50 days after DMBA treatment, probably due to a cell-cycle blockade at the G1/S transition leading to immature stage cell production. A panel of proteins related to cell cycle regulation was evaluated in immature BM cells (Lin(-)) by Western Blot, and DNA damage and repair were measured using an alkaline version of the Comet assay. In Lin(-) cells isolated from AIRmin mice, high levels were found in both p53 and p21 protein contents in contrast with the low levels of CDK4 and Ciclin D1. Evaluation of DNA repair in DMBA-treated BMCs, indicated long-lasting genotoxicity and cytotoxicity in BMC from AIRmin mice and a blockade of cell cycle progression. On the other hand, AIRmax mice have a high capacity of DNA damage repair and protection. These mechanisms can be associated with the differential susceptibility to the toxic and carcinogenic effects of DMBA observed in these mice. PMID:26687588

  5. Acute 7,12-dimethylbenz[a]anthracene exposure causes differential concentration-dependent follicle depletion and gene expression in neonatal rat ovaries

    Energy Technology Data Exchange (ETDEWEB)

    Madden, Jill A. [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States); Hoyer, Patricia B. [Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States); Devine, Patrick J. [INRS—Institut Armand-Frappier Research Centre, University of Quebec, Laval, QC H7V 1B7 (Canada); Keating, Aileen F., E-mail: akeating@iastate.edu [Department of Animal Science, Iowa State University, Ames, IA 50011 (United States); Department of Physiology, University of Arizona, Tucson, AZ 85724 (United States)

    2014-05-01

    Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). After four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKT{sup Thr308} protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. - Highlights: • Acute DMBA exposures induce large primary and/or secondary follicle loss. • Acute DMBA exposure did not impact

  6. Acute 7,12-dimethylbenz[a]anthracene exposure causes differential concentration-dependent follicle depletion and gene expression in neonatal rat ovaries

    International Nuclear Information System (INIS)

    Chronic exposure to the polycyclic aromatic hydrocarbon 7,12-dimethylbenz[a]anthracene (DMBA), generated during combustion of organic matter including cigarette smoke, depletes all ovarian follicle types in the mouse and rat, and in vitro models mimic this effect. To investigate the mechanisms involved in follicular depletion during acute DMBA exposure, two concentrations of DMBA at which follicle depletion has (75 nM) and has not (12.5 nM) been observed were investigated. Postnatal day four F344 rat ovaries were maintained in culture for four days before a single exposure to vehicle control (1% DMSO; CT) or DMBA (12 nM; low-concentration or 75 nM; high-concentration). After four or eight additional days of culture, DMBA-induced follicle depletion was evaluated via follicle enumeration. Relative to control, DMBA did not affect follicle numbers after 4 days of exposure, but induced large primary follicle loss at both concentrations after 8 days; while, the low-concentration DMBA also caused secondary follicle depletion. Neither concentration affected primordial or small primary follicle number. RNA was isolated and quantitative RT-PCR performed prior to follicle loss to measure mRNA levels of genes involved in xenobiotic metabolism (Cyp2e1, Gstmu, Gstpi, Ephx1), autophagy (Atg7, Becn1), oxidative stress response (Sod1, Sod2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Kitlg, cKit, Akt1) 1, 2 and 4 days after exposure. With the exception of Atg7 and cKit, DMBA increased (P < 0.05) expression of all genes investigated. Also, BECN1 and pAKTThr308 protein levels were increased while cKIT was decreased by DMBA exposure. Taken together, these results suggest an increase in DMBA bioactivation, add to the mechanistic understanding of DMBA-induced ovotoxicity and raise concern regarding female low concentration DMBA exposures. - Highlights: • Acute DMBA exposures induce large primary and/or secondary follicle loss. • Acute DMBA exposure did not impact

  7. Repair of DNA treated with. gamma. -irradiation and chemical carcinogens. Progress report, June 1, 1975--January 31, 1976. [MMS, methylnitrosourea, 7-bromomethyl-12-methylbenz(a)-anthracene, Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Goldthwait, D.A.

    1976-02-01

    Enzymatic mechanisms of DNA repair are under investigation. From E. coli an endonuclease active on apurinic acid has been separated from endonuclease II active on DNA treated with methylmethane sulfonate, methylnitrosourea, 7-bromomethyl-12-methylbenz(a)anthracene and ..gamma..-irradiation. Mutants have been identified for each enzyme. The purification of both enzymes is proceeding and the mechanism of action of endonuclease II which has both an N-glycosidase and a phosphodiester hydrolase activity is under investigation. Evidence demonstrating exonuclease III is an enzyme separate from the apurinic acid endonuclease and endonuclease II has been accumulated but this is still under investigation. Work has been completed on 7-bromomethyl-12-methylbenz(a)anthracene treated DNA as a substrate and is being continued on the inhibitory effects of phorbol ester on endonuclease II. Finally, the properties of an enzyme from calf liver active on depurinated DNA have been compared with those of a comparable enzyme from calf thymus. Evidence that they are isozymes has been found.

  8. (1,4,7,10,13,16-Hexaoxacyclooctadecane-κ6Obis(tetrahydrofuran-κOpotassium bis[(1,2,3,4-η-anthracene]cobalt(−I tetrahydrofuran monosolvate

    Directory of Open Access Journals (Sweden)

    Haiyan He

    2014-01-01

    Full Text Available The asymmetric unit of the title compound, [K(C12H24O6(C4H8O2][Co(C14H102]·C4H8O, consists of one cationic potassium complex, one anionic cobalt dianthracene complex and one tetrahydrofuran solvent molecule. The potassium cation is situated at the centre of an 18-crown-6 molecule and between two tetrahydrofuran molecules, the latter coordinating above and below the mean plane formed by the O atoms of the crown ether molecule. The Co atom is coordinated by eight C atoms of two anthracene molecules in an η4 manner. The third free tetrahydrofuran molecule shows orientational disorder on two partially occupied positions [occupancy ratio 0.561 (8:0.439 (8].

  9. Crystal structure of 2-[(3S,4S-4-(anthracen-9-yl-1-(4-methoxyphenyl-2-oxoazetidin-3-yl]-2-aza-2H-phenalene-1,3-dione unknown solvate

    Directory of Open Access Journals (Sweden)

    Ísmail Çelik

    2015-03-01

    Full Text Available The central β-lactam ring of the title compound, C36H24N2O4, is almost planar (r.m.s. deviation = 0.003 Å and makes dihedral angles of 17.17 (19, 89.76 (17 and 78.44 (17° with the benzene ring, the anthracene ring (r.m.s. deviation = 0.003 Å and the 1H-benzo[de]isoquinoline-1,3(2H-dione moiety, which is nearly planar [maximum deviation = 0.098 (2 Å], respectively. The molecular structure is stabilized by an intramolecular C—H...N hydrogen bond. In the crystal, molecules are linked via C—H...π and π–π stacking interactions [centroid–centroid distances = 3.5270 (19 and 3.779 (2 Å], forming a three-dimensional structure. A region of disordered electron density, probably disordered solvent molecules, was treated with the SQUEEZE procedure in PLATON [Spek (2015. Acta Cryst. C71, 9–18], which indicated a solvent cavity of 322 Å3 containing approximately 91 electrons. Their formula mass and unit-cell characteristics were not taken into account during the refinement.

  10. Efficient orange-red organic light-emitting diodes using 9,10-bis[4-(di-4-tert-butylphenylamino)styryl] anthracene as a fluorescent orange-red emitter

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Bo Min; Seo, Ji Hoon; Kim, Jun Ho; Park, Jung Sun [Department of Information Display, Hongik University, Seoul, 121-791 (Korea, Republic of); Lee, Kum Hee; Park, Min Hye [Department of Chemistry, Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of); Yoon, Seung Soo, E-mail: ssyoon@skku.ed [Department of Chemistry, Sungkyunkwan University, Suwon, 440-746 (Korea, Republic of); Kim, Young Kwan, E-mail: kimyk@hongik.ac.k [Department of Information Display, Hongik University, Seoul, 121-791 (Korea, Republic of)

    2010-09-01

    The authors have demonstrated efficient orange-red organic lighting diodes (OLEDs) using a new fluorescent orange-red material, 9,10-bis[4-(di-4-tert-buthylphenylamino)styryl]anthracene (ATBTPA). The optimized orange-red OLED using ATBTPA achieved a maximum external quantum efficiency (EQE) of 3.78%, a current efficiency (CE) of 9.47 cd/A, and Commision Internationale de L'Eclairage (CIE{sub x,y}) coordinates of (0.51, and 0.48) at 1.61 mA/cm{sup 2} in comparison with orange-red OLED using (5,6,11,12)-tetraphenyl-naphthacene (rubrene) which showed a maximum EQE of 1.65%, CE of 4.94 cd/A, and CIE{sub x,y} coordinates of (0.50, and 0.49) at 0.61 mA/cm{sup 2}, respectively. The optimized orange-red device using ATBTPA showed higher efficiency of two times the orange-red device using rubrene due to the efficient Foerster singlet energy transfer from MADN to ATBTPA in comparison with that from MADN to rubrene. This study clearly suggests that ATBTPA is an excellent fluorescent orange-red material for efficient WOLEDs.

  11. Combinatorial chemopreventive effect of butyric acid, nicotinamide and calcium glucarate against the 7,12-dimethylbenz(a)anthracene induced mouse skin tumorigenesis attained by enhancing the induction of intrinsic apoptotic events.

    Science.gov (United States)

    Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

    2015-01-25

    We explored the basis of the combinatorial chemopreventive effect of butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) on mouse skin exposed to 7,12-dimethylbenz(a)anthracene (DMBA). We studied the effects of topical application of DMBA in the presence or absence of BA, NA and CAG on the regulators of apoptosis. DMBA treatment suppressed Bax, Bax/Bcl-2 ratio, release of cyt c, Apaf1, caspase-9, -3 mediated apoptosis. Downregulation of p21 and upregulation of Bcl-2, mut p53 were also observed in only DMBA treated mice. Simultaneous application of BA, NA and CAG induced a mitochondria-mediated apoptosis, characterized by a rise in the Bax, Bax/Bcl-2 ratio, release of cyt c, upregulation of Apaf1 with down-stream activation of caspase-9, -3. Furthermore treatment with BA, NA and CAG demonstrated an upregulation of p21 and downregulation of Bcl-2, mut p53. But this effect was enhanced in the presence of all the three compounds together in combination. Chemoprevention by a combination of BA, NA and CAG by inducing the apoptosis, the natural cell death, suggest the importance of the potential combinational strategies capable of preventing skin tumor development.

  12. Modulatory Effect of Taurine on 7,12-Dimethylbenz(a)Anthracene-Induced Alterations in Detoxification Enzyme System, Membrane Bound Enzymes, Glycoprotein Profile and Proliferative Cell Nuclear Antigen in Rat Breast Tissue.

    Science.gov (United States)

    Vanitha, Manickam Kalappan; Baskaran, Kuppusamy; Periyasamy, Kuppusamy; Selvaraj, Sundaramoorthy; Ilakkia, Aruldoss; Saravanan, Dhiravidamani; Venkateswari, Ramachandran; Revathi Mani, Balasundaram; Anandakumar, Pandi; Sakthisekaran, Dhanapal

    2016-08-01

    The modulatory effect of taurine on 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer in rats was studied. DMBA (25 mg/kg body weight) was administered to induce breast cancer in rats. Protein carbonyl levels, activities of membrane bound enzymes (Na(+) /K(+) ATPase, Ca(2+) ATPase, and Mg(2+) ATPase), phase I drug metabolizing enzymes (cytochrome P450, cytochrome b5, NADPH cytochrome c reductase), phase II drug metabolizing enzymes (glutathione-S-transferase and UDP-glucuronyl transferase), glycoprotein levels, and proliferative cell nuclear antigen (PCNA) were studied. DMBA-induced breast tumor bearing rats showed abnormal alterations in the levels of protein carbonyls, activities of membrane bound enzymes, drug metabolizing enzymes, glycoprotein levels, and PCNA protein expression levels. Taurine treatment (100 mg/kg body weight) appreciably counteracted all the above changes induced by DMBA. Histological examination of breast tissue further supported our biochemical findings. The results of the present study clearly demonstrated the chemotherapeutic effect of taurine in DMBA-induced breast cancer. PMID:27091720

  13. Combinatorial chemopreventive effect of butyric acid, nicotinamide and calcium glucarate against the 7,12-dimethylbenz(a)anthracene induced mouse skin tumorigenesis attained by enhancing the induction of intrinsic apoptotic events.

    Science.gov (United States)

    Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

    2015-01-25

    We explored the basis of the combinatorial chemopreventive effect of butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) on mouse skin exposed to 7,12-dimethylbenz(a)anthracene (DMBA). We studied the effects of topical application of DMBA in the presence or absence of BA, NA and CAG on the regulators of apoptosis. DMBA treatment suppressed Bax, Bax/Bcl-2 ratio, release of cyt c, Apaf1, caspase-9, -3 mediated apoptosis. Downregulation of p21 and upregulation of Bcl-2, mut p53 were also observed in only DMBA treated mice. Simultaneous application of BA, NA and CAG induced a mitochondria-mediated apoptosis, characterized by a rise in the Bax, Bax/Bcl-2 ratio, release of cyt c, upregulation of Apaf1 with down-stream activation of caspase-9, -3. Furthermore treatment with BA, NA and CAG demonstrated an upregulation of p21 and downregulation of Bcl-2, mut p53. But this effect was enhanced in the presence of all the three compounds together in combination. Chemoprevention by a combination of BA, NA and CAG by inducing the apoptosis, the natural cell death, suggest the importance of the potential combinational strategies capable of preventing skin tumor development. PMID:25478867

  14. Modulation of miR-203 and its regulators as a function of time during the development of 7, 12 dimethylbenz [a] anthracene induced mouse skin tumors in presence or absence of the antitumor agents.

    Science.gov (United States)

    Tiwari, Prakash; Gupta, Krishna P

    2014-07-15

    We investigated the chemopreventive effects of naturally occurring compounds like butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) individually or in combination in 7, 12-dimethylbenz [a] anthracene (DMBA) treated mouse skin at 4 and 16 weeks, the time before and after the tumor development. DMBA application did not show any skin tumors at 4 weeks but well defined tumors appeared at 16 weeks. BA, NA or CAG prevented the tumor development significantly but the protection was highly enhanced when all these compounds were given together. In order to see the molecular changes progressing with tumors, we showed the downregulation of tumor suppressor miR-203 at 16 weeks and upregulation of histone deacetylases (HDAC), DNA methyltransferase, promoter methylation of miR-203 at 4 or 16 weeks. Regulators of micro RNA biogenesis such as DICER1 and Ago2 were also deregulated by DMBA. Proto-oncogene c-myc and BMI1 were upregulated and tumor suppressor gene p16 was downregulated by DMBA as a function of time. Effects of BA, NA or CAG were more pronounced after 16 weeks as compared to 4 weeks in preventing the tumor development and altered gene expression. Concomitant administration of BA, NA and CAG tried to prevent these alterations more effectively than that of individual compound possibly by regulating miR-203 status through epigenetic or biogenetic modulations before and after the tumor development. Study provides a rationale for chemoprevention by combination of different compounds targeting miR-203. PMID:24792773

  15. Crystal structure of 2-[(3S,4S)-4-(anthracen-9-yl)-1-(4-meth-oxy-phen-yl)-2-oxoazetidin-3-yl]-2-aza-2H-phenalene-1,3-dione unknown solvate.

    Science.gov (United States)

    Çelik, Ísmail; Akkurt, Mehmet; Jarrahpour, Aliasghar; Rad, Javad Ameri; Çelik, Ömer

    2015-03-01

    The central β-lactam ring of the title compound, C36H24N2O4, is almost planar (r.m.s. deviation = 0.003 Å) and makes dihedral angles of 17.17 (19), 89.76 (17) and 78.44 (17)° with the benzene ring, the anthracene ring (r.m.s. deviation = 0.003 Å) and the 1H-benzo[de]iso-quinoline-1,3(2H)-dione moiety, which is nearly planar [maximum deviation = 0.098 (2) Å], respectively. The mol-ecular structure is stabilized by an intra-molecular C-H⋯N hydrogen bond. In the crystal, mol-ecules are linked via C-H⋯π and π-π stacking inter-actions [centroid-centroid distances = 3.5270 (19) and 3.779 (2) Å], forming a three-dimensional structure. A region of disordered electron density, probably disordered solvent mol-ecules, was treated with the SQUEEZE procedure in PLATON [Spek (2015 ▶). Acta Cryst. C71, 9-18], which indicated a solvent cavity of 322 Å(3) containing approximately 91 electrons. Their formula mass and unit-cell characteristics were not taken into account during the refinement. PMID:25844239

  16. Evaluation of 3-(4'-(4″-fluorophenyl)-6'-phenylpyrimidin-2'-yl)-2-phenylthiazolidin-4-one for in vivo modulation of biomarkers of chemoprevention in the 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis.

    Science.gov (United States)

    Thanusu, J; Kanagarajan, V; Nagini, S; Gopalakrishnan, M

    2011-06-01

    A new bis heterocycle comprising both bioactive 2-aminopyrimidine and thiazolidin-4-one nuclei namely 3-(4'-(4″-fluorophenyl)-6'-phenylpyrimidin-2'-yl)-2-phenylthiazolidin-4-one 3 was synthesized, characterized with the help of melting point, elemental analysis, FT-IR, MS, one-dimensional NMR ((1)H, (13)C) spectra and we evaluated the chemopreventive potential of 3-(4'-(4″-fluorophenyl)-6'-phenylpyrimidin-2'-yl)-2-phenylthiazolidin-4-one based on in vivo inhibitory effects on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinogenesis. Administration of 3 effectively suppressed oral carcinogenesis initiated with DMBA as revealed by the reduced incidence of neoplasms. Lipid peroxidation, glutathione (GSH) content, and the activities of glutathione peroxidase (GPx), glutathione S-transferase (GST) were used to biomonitor the chemopreventive potential of 3. Lipid peroxidation was found to be significantly decreased, whereas GSH, GPx, GST, and GGT were elevated in the oral mucosa of tumor-bearing animals. Our data suggest that 3 may exert its chemopreventive effects in the oral mucosa by modulation of lipid peroxidation and enhancing the levels of GSH, GPx, and GST. PMID:21028942

  17. Modulatory Effect of Taurine on 7,12-Dimethylbenz(a)Anthracene-Induced Alterations in Detoxification Enzyme System, Membrane Bound Enzymes, Glycoprotein Profile and Proliferative Cell Nuclear Antigen in Rat Breast Tissue.

    Science.gov (United States)

    Vanitha, Manickam Kalappan; Baskaran, Kuppusamy; Periyasamy, Kuppusamy; Selvaraj, Sundaramoorthy; Ilakkia, Aruldoss; Saravanan, Dhiravidamani; Venkateswari, Ramachandran; Revathi Mani, Balasundaram; Anandakumar, Pandi; Sakthisekaran, Dhanapal

    2016-08-01

    The modulatory effect of taurine on 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer in rats was studied. DMBA (25 mg/kg body weight) was administered to induce breast cancer in rats. Protein carbonyl levels, activities of membrane bound enzymes (Na(+) /K(+) ATPase, Ca(2+) ATPase, and Mg(2+) ATPase), phase I drug metabolizing enzymes (cytochrome P450, cytochrome b5, NADPH cytochrome c reductase), phase II drug metabolizing enzymes (glutathione-S-transferase and UDP-glucuronyl transferase), glycoprotein levels, and proliferative cell nuclear antigen (PCNA) were studied. DMBA-induced breast tumor bearing rats showed abnormal alterations in the levels of protein carbonyls, activities of membrane bound enzymes, drug metabolizing enzymes, glycoprotein levels, and PCNA protein expression levels. Taurine treatment (100 mg/kg body weight) appreciably counteracted all the above changes induced by DMBA. Histological examination of breast tissue further supported our biochemical findings. The results of the present study clearly demonstrated the chemotherapeutic effect of taurine in DMBA-induced breast cancer.

  18. Modulation of miR-203 and its regulators as a function of time during the development of 7, 12 dimethylbenz [a] anthracene induced mouse skin tumors in presence or absence of the antitumor agents

    International Nuclear Information System (INIS)

    We investigated the chemopreventive effects of naturally occurring compounds like butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) individually or in combination in 7, 12-dimethylbenz [a] anthracene (DMBA) treated mouse skin at 4 and 16 weeks, the time before and after the tumor development. DMBA application did not show any skin tumors at 4 weeks but well defined tumors appeared at 16 weeks. BA, NA or CAG prevented the tumor development significantly but the protection was highly enhanced when all these compounds were given together. In order to see the molecular changes progressing with tumors, we showed the downregulation of tumor suppressor miR-203 at 16 weeks and upregulation of histone deacetylases (HDAC), DNA methyltransferase, promoter methylation of miR-203 at 4 or 16 weeks. Regulators of micro RNA biogenesis such as DICER1 and Ago2 were also deregulated by DMBA. Proto-oncogene c-myc and BMI1 were upregulated and tumor suppressor gene p16 was downregulated by DMBA as a function of time. Effects of BA, NA or CAG were more pronounced after 16 weeks as compared to 4 weeks in preventing the tumor development and altered gene expression. Concomitant administration of BA, NA and CAG tried to prevent these alterations more effectively than that of individual compound possibly by regulating miR-203 status through epigenetic or biogenetic modulations before and after the tumor development. Study provides a rationale for chemoprevention by combination of different compounds targeting miR-203. - Highlights: • DMBA modulates miR-203 and its regulator before and after the onset of tumors. • Suppression of miR-203 and p16 could be the result of gene promoter methylation. • BA, NA or CAG prevents the effects of DMBA. • Combination of BA, NA or CAG is more effective in preventing the DMBA modulations

  19. The effect of Plantago major Linnaeus on serum total sialic acid, lipid-bound sialic acid, some trace elements and minerals after administration of 7,12-dimethylbenz(a)anthracene in rats.

    Science.gov (United States)

    Oto, Gokhan; Ekin, Suat; Ozdemir, Hulya; Levent, Abdulkadir; Berber, Ismet

    2012-05-01

    The present study was designed to evaluate the effect of Plantago major Linnaeus (PM) extract on serum total sialic acid (TSA), lipid-bound sialic acid (LSA), some trace elements (copper (Cu), zinc (Zn) and iron) and mineral levels (magnesium, calcium and sodium) in Wistar albino rat administrated 7,12-dimethylbenz(a)anthracene (DMBA). Rats were divided into three equal groups (n = 6). Group I comprised the control group, group II was treated with DMBA (100 mg/kg, single dose) and group III was treated with DMBA (100 mg/kg single dose) and aqueous extract of PM 100 mg/kg/day for 60 days. After 60 days, statistical analyses showed that TSA and LSA levels in DMBA and DMBA + PM groups were significantly higher compared to the control group (TSA: p < 0.01, p < 0.05; LSA: p < 0.05, p < 0.05, respectively). Serum Zn levels were decreased in subjects treated with DMBA (p < 0.01) and DMBA + PM (p < 0.05) compared to the control group values. Serum Cu levels were increased in DMBA group and PM-treated group compared to the control group values. The results of this investigation showed that the levels of TSA and LSA changed significantly, which are sensitive markers for detecting the toxic effects of DMBA. On the other hand, observed decline in Zn levels in rats from DMBA + PM group might be due to decreased generation of free radicals and oxidative stress. Results from this study suggest that PM may be partially effective in preventing carcinogenesis initiated by environmental carcinogen DMBA. PMID:21996710

  20. A Comparative Account of the Kinetics of Light-Induced E-Z Isomerization of an Anthracene-Based Organogelator in Sol, Gel, Xerogel, and Powder States: Fiber to Crystal Transformation.

    Science.gov (United States)

    Mondal, Sanjoy; Chakraborty, Priyadarshi; Das, Sujoy; Bairi, Partha; Nandi, Arun K

    2016-05-31

    The organogel of (E)-N'-(anthracene-10-ylmethylene)-3,4,5-tris(dodecyloxy)benzohydrazide (I) in methyl cyclohexane having a fibrillar network structure exhibits excellent fluorescence, which decreases sharply with time upon photoirradiation at λ = 365 nm. It has been attributed to the transformation of the E isomer of I to the Z isomer, and the kinetics of E-Z isomerization are compared for the sol, gel, xerogel, and powder states. The rate constants at different temperatures are measured from Avrami plots and its increase with an increase in temperature, indicating temperature acts as a promoter for photoirradiated E-Z isomeization along the imine (C═N) bond. In the powder form, the rate constant values are the lowest compared to those of other states for all temperatures and the xerogels exhibit the highest rate of E-Z isomerization. The rate constants of sol and gel states mostly lie between the two. The wide-angle X-ray scattering pattern changes after ultraviolet (UV) irradiation with the generation of new sharp peaks whose intensities increase with an increase in irradiation time. A polarized optical microscopic study indicates formation of small crystalline dots on the fibers in the gels, dendritic morphology on the xerogel fibers, and large needlelike morphology at the surface boundary of the solid. The dried I gel exhibits a melting peak at 96.7 °C, but upon irradiation, two peaks are observed at 98.5 and 152.7 °C; the latter has been attributed to the melting of crystals of Z isomers. Similar higher melting peaks are observed both for the xerogel and for powders after UV irradiation; the powders exhibit the highest meting peak at 159.4 °C. Possible reasons for the variation of rate constant values in the four different states and the difference in morphology and melting points of crystals of Z isomers of I are discussed. PMID:27159227

  1. Preventive effects of butyric acid, nicotinamide, calcium glucarate alone or in combination during the 7, 12-dimethylbenz (a) anthracene induced mouse skin tumorigenesis via modulation of K-Ras-PI3K-AKTpathway and associated micro RNAs.

    Science.gov (United States)

    Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

    2016-02-01

    Skin cancer is among the most common cancers worldwide and identifiable molecular changes for early and late stage of skin tumorigenesis can suggest the better targets for its control. In this study, we investigated the status of K-Ras-PI3K-AKTpathway followed by NF-κB, cyclin D1, MMP-9 and regulatory micro RNA during 7, 12-dimethylbenz[a]anthracene (DMBA) induced mouse skin tumorigenesis and its prevention by butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG), individually or in combination with respect to time. DMBA upregulated the K-Ras, PI3K, Akt, NF-κB, cyclin D1 and MMP-9, but downregulated the PTEN in a time dependent manner. DMBA also reduced the levels of micoRNA let-7a but induced the levels of miR-21 and miR-20a as a function of time. BA, NA and CAG were found to prevent DMBA induced changes, but they were most effective when used together in a combination. Reduced let-7a and miR-211 were correlated with the overexpression of K-Ras and MMP-9. Overexpression of miR-21 and miR-20a was correlated with the down regulation of PTEN and overexpression of Cyclin D1. Collectively, the enhanced chemopreventive potential of natural compound in combination via regulation of K-Ras-PI3K-AKTpathway along with regulatory micro RNAs provide a newer and effective mean for cancer management.

  2. Modulation of miR-203 and its regulators as a function of time during the development of 7, 12 dimethylbenz [a] anthracene induced mouse skin tumors in presence or absence of the antitumor agents

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, Prakash; Gupta, Krishna P., E-mail: krishnag522@yahoo.co.in

    2014-07-15

    We investigated the chemopreventive effects of naturally occurring compounds like butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG) individually or in combination in 7, 12-dimethylbenz [a] anthracene (DMBA) treated mouse skin at 4 and 16 weeks, the time before and after the tumor development. DMBA application did not show any skin tumors at 4 weeks but well defined tumors appeared at 16 weeks. BA, NA or CAG prevented the tumor development significantly but the protection was highly enhanced when all these compounds were given together. In order to see the molecular changes progressing with tumors, we showed the downregulation of tumor suppressor miR-203 at 16 weeks and upregulation of histone deacetylases (HDAC), DNA methyltransferase, promoter methylation of miR-203 at 4 or 16 weeks. Regulators of micro RNA biogenesis such as DICER1 and Ago2 were also deregulated by DMBA. Proto-oncogene c-myc and BMI1 were upregulated and tumor suppressor gene p16 was downregulated by DMBA as a function of time. Effects of BA, NA or CAG were more pronounced after 16 weeks as compared to 4 weeks in preventing the tumor development and altered gene expression. Concomitant administration of BA, NA and CAG tried to prevent these alterations more effectively than that of individual compound possibly by regulating miR-203 status through epigenetic or biogenetic modulations before and after the tumor development. Study provides a rationale for chemoprevention by combination of different compounds targeting miR-203. - Highlights: • DMBA modulates miR-203 and its regulator before and after the onset of tumors. • Suppression of miR-203 and p16 could be the result of gene promoter methylation. • BA, NA or CAG prevents the effects of DMBA. • Combination of BA, NA or CAG is more effective in preventing the DMBA modulations.

  3. The relationship between sirtuin 1 (SIRT1 expression and tumor size, Proliferating Cell Nuclear Antigen (PCNA expression and histological grading in rat breast carcinoma induced by dimethylbenz(anthracene (DMBA

    Directory of Open Access Journals (Sweden)

    Novrita Padauleng Dewajani Purnomosari, Sri Herwiyanti Harjadi, Irianiwati, Sitarina Widyarini

    2014-08-01

    Full Text Available Controversy regarding the role of SIRT1 in pathology of cancers exists and is still under debate.SIRT1 could act as either a tumor supressor or tumor promotor. This study was conducted toevaluate the relationship between SIRT1 expression and tumor size, Proliferating Cell NuclearAntigen (PCNA expression and histological grading in rat breast carcinoma induced bydimethylbenz(áanthracene (DMBA. Thirty female Sprague Dawley rats were randomly allocatedinto three groups with 10 rats in each group. Group 1 as negative control was just fed thestandard food. Group 2 as vehicle control was fed the standard food and corn oil. Group 3 asinduction group was fed the standard food and induced with DMBA at dose of 20 mg/kg bodyweight (BW in corn oil twice a week for five weeks. All rats were palpated weekly to determinethe appearance, size and location of tumors. Sixteen weeks after DMBA induction rats weresacrified and histological preparations of the breast carcinoma tissue were then processed forSIRT1 and PCNA expression examination as well as histological grading. The result showed thatSIRT1 expression was significantly higher in breast carcinoma tissue compared to normal gland(26.12 vs 0.05; p = 0.004. SIRT1-positive was observed mostly in poor histological gradecarcinomas (56.2%, and it was not observed in good histological grade carcinomas. However,there was no significantly difference between SIRT1 and histological grading (p = 0.097; r =0.285. A significant correlation between SIRT1 expression and the tumor size (p =0.009; r=0.877, as well as PCNA expression (p =0.000; r =0.790 was observed. In conclusion, thereis relationship between SIRT1 expression and tumor size as well as PCNA expression in rat breastcarcinoma induced by DMBA.

  4. Preventive effects of butyric acid, nicotinamide, calcium glucarate alone or in combination during the 7, 12-dimethylbenz (a) anthracene induced mouse skin tumorigenesis via modulation of K-Ras-PI3K-AKTpathway and associated micro RNAs.

    Science.gov (United States)

    Tiwari, Prakash; Sahay, Satya; Pandey, Manuraj; Qadri, Syed S Y H; Gupta, Krishna P

    2016-02-01

    Skin cancer is among the most common cancers worldwide and identifiable molecular changes for early and late stage of skin tumorigenesis can suggest the better targets for its control. In this study, we investigated the status of K-Ras-PI3K-AKTpathway followed by NF-κB, cyclin D1, MMP-9 and regulatory micro RNA during 7, 12-dimethylbenz[a]anthracene (DMBA) induced mouse skin tumorigenesis and its prevention by butyric acid (BA), nicotinamide (NA) and calcium glucarate (CAG), individually or in combination with respect to time. DMBA upregulated the K-Ras, PI3K, Akt, NF-κB, cyclin D1 and MMP-9, but downregulated the PTEN in a time dependent manner. DMBA also reduced the levels of micoRNA let-7a but induced the levels of miR-21 and miR-20a as a function of time. BA, NA and CAG were found to prevent DMBA induced changes, but they were most effective when used together in a combination. Reduced let-7a and miR-211 were correlated with the overexpression of K-Ras and MMP-9. Overexpression of miR-21 and miR-20a was correlated with the down regulation of PTEN and overexpression of Cyclin D1. Collectively, the enhanced chemopreventive potential of natural compound in combination via regulation of K-Ras-PI3K-AKTpathway along with regulatory micro RNAs provide a newer and effective mean for cancer management. PMID:26655363

  5. Liver tumors induced in B6C3F{sub 1} mice by benz[a]anthracene and two of its halogenated derivatives contain K-RAS oncogene mutations

    Energy Technology Data Exchange (ETDEWEB)

    Xia, O.; Yi, P.; Zhan, D. [and others

    1997-10-01

    Polycyclic aromatic hydrocarbons (PAHs) and halogenated PAHs are genotoxic environmental contaminants. We previously examined the tumorigenicity of benz[a]anthracene (BA), 7-Cl-BA, and 7-Br-BA in the neonatal mouse tumorigenicity bioassay. Male B6C3F{sub 1} mice were administered i.p. injections at a total dose of 400 nmol per mouse on 1, 8, and 15 days after birth. BA, 7-Cl-BA, and 7-Br-BA induced hepatocellular adenoma in 67, 92, and 96% of the mice, respectively, and induced hepatocellular carcinoma in 15, 100 and 83% of the mice, respectively. In the present study, mRNA was isolated from each of the liver tumors induced by the three compounds, reversed-transcribed to cDNA, and portions of the K- and H-ras oncogene coding sequences were amplified and analyzed for DNA sequence alterations. 92% (11/12) of BA-induced, 79% (19/24) of 7-Cl-BA-induced and 86% (19/22) of 7-Br-BA-induced liver tumors had activated ras protooncogenes. In contrast to the general finding of H-ras mutations in B6C3F{sub 1} mouse liver tumors, all the mutations were at the first base of K-ras codon 13, resulting in a pattern of GGC{yields}CGC. No other ras oncogene mutations were detected. Our results clearly demonstrate that these chemicals induce a unique type of ras (K-ras) oncogene activation in the liver tumors of B6C3F{sub 1} mice.

  6. UV-B辐射和蒽共同作用对三叶浮萍的毒性效应%Joint Toxic Effects of UV-B Radiation and Anthracene on Lemna Minor

    Institute of Scientific and Technical Information of China (English)

    张攀; 王仁君; 周晶; 沙未来

    2012-01-01

    本实验采用常见的三叶浮萍作为实验材料,研究了多环芳烃( PAHs)蒽(Anthracene)与UV-B辐射单独胁迫和共同作用对浮萍(Lemna minor)的毒性效应.浮萍的初始个数为45个,蒽的质量浓度分别设为0、0.5、2.5、5、10、20mg·L-1,设计三个个平行组,每组辐射剂量均是810 J·m-2.结果表明,蒽、紫外线单独胁迫都会对浮萍产生损害,使其生长量有下降趋势.当辐射剂量达到810 J·m-2时,叶绿素含量达到最大,随着辐射剂量的增加,叶绿素含量减少.且随着蒽浓度的不断增大,对浮萍生长的其抑制作用更加明显,存在着明显的剂量-效应关系.蒽和UV-B辐射共同作用对浮萍产生抑制作用,并且随着蒽浓度的增加,抑制作用逐渐增强.

  7. A Comparative Account of the Kinetics of Light-Induced E-Z Isomerization of an Anthracene-Based Organogelator in Sol, Gel, Xerogel, and Powder States: Fiber to Crystal Transformation.

    Science.gov (United States)

    Mondal, Sanjoy; Chakraborty, Priyadarshi; Das, Sujoy; Bairi, Partha; Nandi, Arun K

    2016-05-31

    The organogel of (E)-N'-(anthracene-10-ylmethylene)-3,4,5-tris(dodecyloxy)benzohydrazide (I) in methyl cyclohexane having a fibrillar network structure exhibits excellent fluorescence, which decreases sharply with time upon photoirradiation at λ = 365 nm. It has been attributed to the transformation of the E isomer of I to the Z isomer, and the kinetics of E-Z isomerization are compared for the sol, gel, xerogel, and powder states. The rate constants at different temperatures are measured from Avrami plots and its increase with an increase in temperature, indicating temperature acts as a promoter for photoirradiated E-Z isomeization along the imine (C═N) bond. In the powder form, the rate constant values are the lowest compared to those of other states for all temperatures and the xerogels exhibit the highest rate of E-Z isomerization. The rate constants of sol and gel states mostly lie between the two. The wide-angle X-ray scattering pattern changes after ultraviolet (UV) irradiation with the generation of new sharp peaks whose intensities increase with an increase in irradiation time. A polarized optical microscopic study indicates formation of small crystalline dots on the fibers in the gels, dendritic morphology on the xerogel fibers, and large needlelike morphology at the surface boundary of the solid. The dried I gel exhibits a melting peak at 96.7 °C, but upon irradiation, two peaks are observed at 98.5 and 152.7 °C; the latter has been attributed to the melting of crystals of Z isomers. Similar higher melting peaks are observed both for the xerogel and for powders after UV irradiation; the powders exhibit the highest meting peak at 159.4 °C. Possible reasons for the variation of rate constant values in the four different states and the difference in morphology and melting points of crystals of Z isomers of I are discussed.

  8. Metformin inhibits 7,12-dimethylbenz[a]anthracene-induced breast carcinogenesis and adduct formation in human breast cells by inhibiting the cytochrome P4501A1/aryl hydrocarbon receptor signaling pathway

    International Nuclear Information System (INIS)

    Recent studies have established that metformin (MET), an oral anti-diabetic drug, possesses antioxidant activity and is effective against different types of cancer in several carcinogen-induced animal models and cell lines. However, whether MET can protect against breast cancer has not been reported before. Therefore, the overall objectives of the present study are to elucidate the potential chemopreventive effect of MET in non-cancerous human breast MCF10A cells and explore the underlying mechanism involved, specifically the role of cytochrome P4501A1 (CYP1A1)/aryl hydrocarbon receptor (AhR) pathway. Transformation of the MCF10A cells into initiated breast cancer cells with DNA adduct formation was conducted using 7,12-dimethylbenz[a]anthracene (DMBA), an AhR ligand. The chemopreventive effect of MET against DMBA-induced breast carcinogenesis was evidenced by the capability of MET to restore the induction of the mRNA levels of basic excision repair genes, 8-oxoguanine DNA glycosylase (OGG1) and apurinic/apyrimidinic endonuclease1 (APE1), and the level of 8-hydroxy-2-deoxyguanosine (8-OHdG). Interestingly, the inhibition of DMBA-induced DNA adduct formation was associated with proportional decrease in CYP1A1 and in NAD(P)H:quinone oxidoreductase 1 (NQO1) gene expression. Mechanistically, the involvements of AhR and nuclear factor erythroid 2-related factor-2 (Nrf2) in the MET-mediated inhibition of DMBA-induced CYP1A1 and NQO1 gene expression were evidenced by the ability of MET to inhibit DMBA-induced xenobiotic responsive element and antioxidant responsive element luciferase reporter gene expression which suggests an AhR- and Nrf2-dependent transcriptional control. However, the inability of MET to bind to AhR suggests that MET is not an AhR ligand. In conclusion, the present work shows a strong evidence that MET inhibits the DMBA-mediated carcinogenicity and adduct formation by inhibiting the expression of CYP1A1 through an AhR ligand-independent mechanism

  9. Metformin inhibits 7,12-dimethylbenz[a]anthracene-induced breast carcinogenesis and adduct formation in human breast cells by inhibiting the cytochrome P4501A1/aryl hydrocarbon receptor signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Maayah, Zaid H. [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Ghebeh, Hazem [Stem Cell & Tissue Re-Engineering, King Faisal Specialist Hospital and Research Center, Riyadh 11211 (Saudi Arabia); Alhaider, Abdulqader A. [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Camel Biomedical Research Unit, College of Pharmacy and Medicine, King Saud University, Riyadh 11451 (Saudi Arabia); El-Kadi, Ayman O.S. [Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta, Edmonton (Canada); Soshilov, Anatoly A.; Denison, Michael S. [Department of Environmental Toxicology, University of California at Davis, Davis, CA 95616 (United States); Ansari, Mushtaq Ahmad [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia); Korashy, Hesham M., E-mail: hkorashy@ksu.edu.sa [Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451 (Saudi Arabia)

    2015-04-15

    Recent studies have established that metformin (MET), an oral anti-diabetic drug, possesses antioxidant activity and is effective against different types of cancer in several carcinogen-induced animal models and cell lines. However, whether MET can protect against breast cancer has not been reported before. Therefore, the overall objectives of the present study are to elucidate the potential chemopreventive effect of MET in non-cancerous human breast MCF10A cells and explore the underlying mechanism involved, specifically the role of cytochrome P4501A1 (CYP1A1)/aryl hydrocarbon receptor (AhR) pathway. Transformation of the MCF10A cells into initiated breast cancer cells with DNA adduct formation was conducted using 7,12-dimethylbenz[a]anthracene (DMBA), an AhR ligand. The chemopreventive effect of MET against DMBA-induced breast carcinogenesis was evidenced by the capability of MET to restore the induction of the mRNA levels of basic excision repair genes, 8-oxoguanine DNA glycosylase (OGG1) and apurinic/apyrimidinic endonuclease1 (APE1), and the level of 8-hydroxy-2-deoxyguanosine (8-OHdG). Interestingly, the inhibition of DMBA-induced DNA adduct formation was associated with proportional decrease in CYP1A1 and in NAD(P)H:quinone oxidoreductase 1 (NQO1) gene expression. Mechanistically, the involvements of AhR and nuclear factor erythroid 2-related factor-2 (Nrf2) in the MET-mediated inhibition of DMBA-induced CYP1A1 and NQO1 gene expression were evidenced by the ability of MET to inhibit DMBA-induced xenobiotic responsive element and antioxidant responsive element luciferase reporter gene expression which suggests an AhR- and Nrf2-dependent transcriptional control. However, the inability of MET to bind to AhR suggests that MET is not an AhR ligand. In conclusion, the present work shows a strong evidence that MET inhibits the DMBA-mediated carcinogenicity and adduct formation by inhibiting the expression of CYP1A1 through an AhR ligand-independent mechanism

  10. Method validation and simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with 7,12 dimethylbenz[a]anthracene and Plantago major L. by high- performance liquid chromatography using diode-array detection.

    Science.gov (United States)

    Levent, Abdulkadi; Oto, Gokhan; Ekin, Suat; Berber, Ismet

    2013-02-01

    A new and simple high-performance liquid chromatography method was developed and validated for the simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with Plantago Major L. and 7,12 dimethylbenz[a]anthracene. High-performance liquid chromatography analysis was performed utilizing an Inertsil ODS3 reversed phase column with methanol-tetrahydrofuran-water as mobile phase under gradient conditions, at 1.5 mL min(-1) flow rate and 25 °C. Diode-array detection was at 325, 450, 290 and 270 nm (retinol and retinyl palmitate), β-carotene, α-tocopherol and vitamin C, respectively and runnig time 18 min. The high-performance liquid chromatography assay and extraction procedure proposed are simple, rapid, sensitive and accurate. The method was then applied for the determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum. Results of this study demonstrated that; at 60th day DMBA-treated group, there was a significant decrease in vitamin levels compared to the levels of control group. A significant increase was observed in vitamin levels of 7,12 dimethylbenz[α]anthracene+Plantago Major L.-treated group compared to the DMBA-treated group. Additionally, the results obtained in the study are found to be in agreement with data reported in the literature.

  11. Method validation and simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with 7,12 dimethylbenz[a]anthracene and Plantago major L. by high- performance liquid chromatography using diode-array detection.

    Science.gov (United States)

    Levent, Abdulkadi; Oto, Gokhan; Ekin, Suat; Berber, Ismet

    2013-02-01

    A new and simple high-performance liquid chromatography method was developed and validated for the simultaneous determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum treated with Plantago Major L. and 7,12 dimethylbenz[a]anthracene. High-performance liquid chromatography analysis was performed utilizing an Inertsil ODS3 reversed phase column with methanol-tetrahydrofuran-water as mobile phase under gradient conditions, at 1.5 mL min(-1) flow rate and 25 °C. Diode-array detection was at 325, 450, 290 and 270 nm (retinol and retinyl palmitate), β-carotene, α-tocopherol and vitamin C, respectively and runnig time 18 min. The high-performance liquid chromatography assay and extraction procedure proposed are simple, rapid, sensitive and accurate. The method was then applied for the determination of retinol, retinyl palmitate, β-carotene, α-tocopherol and vitamin C in rat serum. Results of this study demonstrated that; at 60th day DMBA-treated group, there was a significant decrease in vitamin levels compared to the levels of control group. A significant increase was observed in vitamin levels of 7,12 dimethylbenz[α]anthracene+Plantago Major L.-treated group compared to the DMBA-treated group. Additionally, the results obtained in the study are found to be in agreement with data reported in the literature. PMID:23176060

  12. 纯化9,10-二萘蒽对OLED器件光电性能的影响%Purity Effects on the Electroluminescent Performance of 9,10-Di(2-naphthyl)anthracene

    Institute of Scientific and Technical Information of China (English)

    李瑛; 王文根; 邵明; 王秀如; 汤昊; 孙润光

    2006-01-01

    合成了高稳定性蓝光主体材料9,10-二萘蒽(ADN),研究材料纯化对合成材料光电性能的影响.为进一步分析材料经升华提纯对有机电致发光器件性能的影响,以提纯前后ADN为发光层,以NPB 为空穴传输层,分别制作双层器件Ⅰ(提纯前)和器件Ⅱ(提纯后),器件结构为ITO(100 nm)/NPB(40 nm)/ADN(30 nm)/Alq3(20 nm)/LiF (1 nm) /Al (100 nm), 结果表明提纯后材料PL(Photoluminescence)光谱蓝移了2 nm,半峰全宽54.2 nm,与提纯前一致;杂质影响载流子注入效率和迁移率,对器件光电性能有显著影响,纯化前后器件最大电流效率由1.5 cd/A上升至2.5 cd/A;器件Ⅱ色纯度有较大提高,CIE色坐标由器件Ⅰ(0.15,0.10)移至(0.15, 0.06).实验结果表明材料提纯是优化器件性能的有效手段之一.%Organic light-emitting diode (OLED) has attracted considerable attention due to their unique image quality and market potentials in display application. For the full-color display applications, it is essential to deliver the primary RGB emitters with high luminous efficiency, saturated color chromaticity, among which 9, 10-Di (2-naphthyl) anthracene (ADN) is one of the stable and pure blue emitters. However, little attention has been paid to the influences of ADNs purification on the electroluminescent(EL) performance.Synthesis and purification of ADN were studied. The photoluminescence (PL) and electroluminescence (EL) spectra of ADN synthesized and purified are investigated, respectively. The PL spectrum of ADN purified exhibits an emitting peak at 434 nm with a full-width at half-maxium (FWHM) of 54.2 nm, while the rough material without purification is red shifted to 436 nm with the same FWHM of 54.2 nm. Organic light-emitting diodes (OLEDs) with a structure of indium tin oxide (ITO) (100 nm)/N,N′-biphenyl-N,N′-bis-(1-naphenyl)-[1,1′- biphenyl]-4,4′-diamine (NPB)(40 nm)/ADN(30 nm)/tris(8-quinolinolate)aluminum(Alq3)(20 nm)/LiF(1 nm)/Al(100

  13. Redetermination of (E-3-(anthracen-9-yl-1-(2-hydroxyphenylprop-2-en-1-oneThis paper is dedicated to Her Royal Highness Princess Chulabhorn Walailak of Thailand for her contributions to science on the occasion of her 54th birthday, which fell on July 4th, 2011.

    Directory of Open Access Journals (Sweden)

    Jaruwan Joothamongkhon

    2011-10-01

    Full Text Available The redetermined structure of title chalcone derivative, C23H16O2, corrects errors in the title, scheme and synthesis in the previous report of the same structure [Jasinski et al. (2011. Acta Cryst. E67, o795]. There are two independent molecules in the asymmetric unit with slight differences in bond lengths and angles. The dihedral angle between the benzene ring and the anthracene ring system is 73.30 (4° in one molecule and 73.18 (4° in the other. Both molecules feature an intramolecular O—H...O hydrogen bond, which generates an S(6 ring. In the crystal, molecules are arranged into sheets lying parallel to the ac plane and further stacked along the b axis by π–π interactions with centroid–centroid distances in the range 3.6421 (6–3.7607 (6 Å. The crystal structure is further stabilized by C—H...π interactions. There are also C...O [3.2159 (15 Å] short contacts.

  14. Contaminação do solo com antraceno e creosoto e o crescimento vegetal e a colonização micorrízica pelo Glomus etunicatum Soil contamination with anthracene and creosote: impact on plant growth and mycorrhizal colonization by Glomus etunicatum

    Directory of Open Access Journals (Sweden)

    Alessandra Monteiro de Paula

    2007-08-01

    -derived, polycyclic aromatic hydrocarbons (PAHs, is a growing problem with serious environmental consequences. To evaluate the environmental impact of these products it is important to understand their effects on plants and the associated microbiota. The effects of PAHs on growth and mycorrhizal colonization of Brachiaria brizantha and Pueraria phaseoloides were evaluated here. Two PAHs, anthracene and creosote, were applied to a soil infested with the mycorrhizal fungus Glomus etunicatum at varied concentrations: anthracene (0; 0.25; 0.5; 0.75 and 1 g kg-1 soil and creosote (0; 0.5; 1; 2 and 3 g kg-1 soil. This soil was packed into plastic tubes (290 cm³ where test plants were sown and grown for six weeks. It was found that anthracene did not affect pueraria growth and had a slight stimulus on brachiaria growth at the lowest concentration, whereas creosote had no effect on pueraria either, but inhibited brachiaria growth. Both contaminants inhibited mycorrhizal colonization in pueraria by about 90 %, compared to the control. At concentrations below those found in contaminated soils, AM colonization was inhibited by 50 %. The potential impact of these products on plant-AM fungus relationships is quite evident here. No colonization was found in brachiaria, regardless of the presence of PAHs. The results showed a differentiated sensitivity of the plants to the contaminants and their marked negative effect on G. etunicatum root colonization. In the evaluated concentration range, pueraria was insensitive to both compounds, which indicates the species for further studies on phytoremediation of areas under the impact of these contaminants.

  15. Renoprotective effects of Moringa oleifera pods in 7,12-dimethylbenz[a]anthracene-exposed mice%油椒木豆荚提取物对二甲基苯蒽诱导小鼠肾组织损伤的保护作用

    Institute of Scientific and Technical Information of China (English)

    Veena Sharma; Ritu Paliwal; Pracheta Janmeda; Shatruhan Sharma

    2012-01-01

    目的:通过二甲基苯蒽(7,12-dimethylbenz[a]anthracene,DMBA)诱导雄性白化小鼠肾组织损伤来研究油椒木豆荚的水乙醇提取物对肾脏的保护作用.方法:予实验小鼠口服15 mg/kg DMBA两周前,分别予200和400 mg/kg的油椒木豆荚的水乙醇提取物以及浓度为0.5%和1%的叔丁基对羟基茴香醚灌胃.测定各组小鼠细胞色素(cytochrome,Cyt)P450及Cytb5、还原型谷光甘肽(reduced glutathione,GSH)、谷胱甘肽转移酶(glutathione-S-transferase,GST)以及肾组织天冬氨酸氨基转移酶( aspartate transaminase,AST)、丙氨酸氨基转移酶(alanine transaminase,ALT)、碱性磷酸酶(alkaline phosphatase,ALP)活性及总胆固醇和蛋白质含量.结果:口服15 mg/kg的DMBA可显著增加小鼠Cyt P450和Cyt b5的浓度(P<0.01).小鼠肾组织GSH、GST活性显著降低(P<0.01,P<0.05).实验小鼠在口服DMBA后,肾组织AST、ALT、ALP活性和蛋白质含量也显著降低,总胆固醇含量则显著增加(P<0.01).但是经200和400 mg/kg油椒木豆荚提取物预处理14 d的实验小鼠,其由DMBA诱发的各项组织生化指标变化发生显著逆转(P<0.01).结论:油椒木豆荚的提取物可通过提高细胞抗氧化活性、减少自由基的生成来减少DMBA的毒副作用,起到保护肾组织的作用.%OBJECTIVE:To investigate the potential of hydroethanolic extract of Moringa oleifera (MOHE) against 7,12-dimethylbenz[a]anthracene (DMBA)-induced toxicity in male Swiss albino mice.METHODS:Experimental mice were respectively pretreated with 200 and 400 mg/kg of MOHE,and 0.5% and 1% of butylated hydroxyanisole (BHA) for two weeks prior to the administration of 15 mg/kg of DMBA,respectively.Levels of xenobiotic metabolizing enzymes such as cytochrome (Cyt) P450 and Cyt b5,activities of reduced glutathione (GSH) and glutathione-S-transferase (GST) and renal aspartate aminotransaminase (AST),alanine aminotransaminase (ALT) and alkaline phosphatase (ALP),and content of

  16. Ethyl (E)-3-(anthracen-9-yl)prop-2-enoate

    Science.gov (United States)

    Bugenhagen, Bernhard; Al Jasem, Yosef; Hindawi, Bassam al; Al Rawashdeh, Nathir; Thiemann, Thies

    2013-01-01

    In the asymmetric unit of the title compound, C19H16O2, there are two symmetry-independent mol­ecules (A and B) that differ in the conformation of the ester eth­oxy group. In the crystal, the mol­ecules form inversion dimers via pairs of C—H⋯O inter­actions. Within the dimers, the anthracenyl units have inter­planar distances of 0.528 (2) and 0.479 (2) Å for dimers of mol­ecules A and B, respectively. Another short C—H⋯O contact between symmetry-independent dimers links them into columns parallel to [10-1]. These columns are arranged into (111) layers and there are π–π stacking inter­actions [centroid–centroid distances = 3.6446 (15) and 3.6531 (15) Å] between the anthracenyl units from the neighbouring columns. In addition, there are C—H⋯π inter­actions between the anthracenyl unit of dimers A and dimers B within the same column. PMID:23476390

  17. Ethyl (E)-3-(anthracen-9-yl)prop-2-enoate

    OpenAIRE

    Nathir Al Rawashdeh; Bassam al Hindawi; Yosef Al Jasem; Bernhard Bugenhagen; Thies Thiemann

    2012-01-01

    In the asymmetric unit of the title compound, C19H16O2, there are two symmetry-independent molecules (A and B) that differ in the conformation of the ester ethoxy group. In the crystal, the molecules form inversion dimers via pairs of C—H...O interactions. Within the dimers, the anthracenyl units have interplanar distances of 0.528 (2) and 0.479 (2) Å for dimers of molecules A and B, respectively. Another short C—H...O contact between symmetry-independent di...

  18. Ethyl (E-3-(anthracen-9-ylprop-2-enoate

    Directory of Open Access Journals (Sweden)

    Nathir Al Rawashdeh

    2013-01-01

    Full Text Available In the asymmetric unit of the title compound, C19H16O2, there are two symmetry-independent molecules (A and B that differ in the conformation of the ester ethoxy group. In the crystal, the molecules form inversion dimers via pairs of C—H...O interactions. Within the dimers, the anthracenyl units have interplanar distances of 0.528 (2 and 0.479 (2 Å for dimers of molecules A and B, respectively. Another short C—H...O contact between symmetry-independent dimers links them into columns parallel to [10-1]. These columns are arranged into (111 layers and there are π–π stacking interactions [centroid–centroid distances = 3.6446 (15 and 3.6531 (15 Å] between the anthracenyl units from the neighbouring columns. In addition, there are C—H...π interactions between the anthracenyl unit of dimers A and dimers B within the same column.

  19. Highly brominated anthracenes as precursors for the convenient synthesis of 2,9,10-trisubstituted anthracene derivatives

    Directory of Open Access Journals (Sweden)

    2008-12-01

    Full Text Available When 9,10-dibromoanthracene was treated with bromine in CCl4 without a catalyst, 1,2,3,4,9,10-hexabromo-1,2,3,4-tetrahydroanthracene (3 was obtained in 95% yield in the absence of other stereoisomers or rearomatization products. We investigated the base-induced elimination reaction of hexabromide 3 under various conditions. Pyridine-induced elimination of hexabromide 3 afforded 2,9,10-tribromoanthracene (12 in 75% yield, and tribromide 12 was transformed to trimethoxy compound 13 and trinitrile 14 by copper-assisted nucleophilic substitution reactions.

  20. In situ Determination of Anthracene Adsorbed onto Mangrove Root Surface Micro-zone Using Microscopic Fluorescence Spectrometric Analysis System%显微荧光光谱原位测定红树植物根表面微区中的蒽

    Institute of Scientific and Technical Information of China (English)

    谭华东; 李锐龙; 朱亚先; 张勇

    2016-01-01

    A microscopic fluorescence spectrometric analysis ( MFSA) system was set in the laboratory. A novel method for in situ determination of Anthracene ( Ant) adsorbed onto root surface micro-zone of two kinks of mangrove plant, named Kandelia obovata ( K. obovata) and Avicennia marina ( A. marina) by MFSA was established. Fluorescence spectra of Ant adsorbed on root surface micro-zone were obtained by synchronous scanning mode. The signal to noise (S/N) of Ant (5. 3 pg/μm2) adsorbed on K. obovata and A. marina root surface micro-zone increased up to 5. 5 and 6. 8 while wavelength offset (△λ) both were at 60 nm, respectively. The linear dynamic ranges of established method were 5. 3-63. 2 pg/μm2 for K. obovata and 10. 5-52. 6 pg/μm2 for A. marina, with the detection limits of 1. 1 pg/μm2 and 5. 5 pg/μm2 , respectively. The relative standard deviations were both less than 12 . 5% ( n=9 ) , and the recoveries were 98 . 1% -117. 0% and 81. 2%-110. 9%, respectively. The result showed that the MFSA system had ability to obtain quantitative information of fluorescence spectra and fluorescence image of Ant adsorbed onto plant roots surface micro-zone.%自行搭建显微荧光光谱分析( Microscopic fluorescence spectrometric analysis, MFSA)系统,并将其用于吸附于红树植物秋茄( Kandelia obovata, K. obovata)和白骨壤( Avicennia marina, A. marina)根表面微区中蒽( Anthrancene, Ant)的原位测定。在同步扫描模式下,以波长差为60 nm,吸附于K. obovata和A. marina根表面微区中Ant(5.3 pg/μm2)的荧光信号有最大信噪比(5.5和6.8)。所建方法的线性范围分别为5.3 ~63.2 pg/μm2和10.5~52.6 pg/μm2,检出限分别为1.1和5.5 pg/μm2,相对标准偏差均小于12.5%(n=9),加标回收率分别为98.1%~117.0%和81.2%~110.9%。结果表明,搭建的MFSA系统具备原位获取植物根表面微区Ant荧光光谱定量信息和荧光图像信息的能力。

  1. Synthesis and Photoelectrical Properties of Two Potential Solution-Processed Blue Fluorescent Emitters Based on Fluorene-Arylamine Derivatives End-Capped with Anthracene/Pyrene Molecules%基于蒽/芘分子封端的芴-芳胺衍生物的可溶液加工的蓝光材料的合成与光电性质

    Institute of Scientific and Technical Information of China (English)

    欧阳密; 吴启超; 余振伟; 李洪飞; 张诚

    2014-01-01

    Two novel potential solution-processed blue fluorescent emitters composed of a core fluorene-diphenylamine unit capped with either anthracene (FAn) or pyrene (FPy) were synthesized and characterized. They were both soluble in common organic solvents and solutions gave smooth films after spin coating. Their optical properties in solution and in the film were investigated by UV-visible and photoluminescence (PL) spectroscopy. The PL emission maximum of FAn and FPy in the film state were found to be 449 and 465 nm, respectively. The electrochemical properties of the as-prepared samples were studied by cyclic voltammetry. The estimated highest occupied molecular orbital (HOMO) energy levels were-5.37 and-5.36 eV for FAn and FPy, respectively. These results indicate that the introduction of diphenylamine effectively prevents plane stacking of the molecules in the solid state, which suppresses the formation of long-wavelength aggregates, and the high HOMO levels enhance the hole-injection ability of the compounds. The results of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) indicate that the two materials have excellent thermal stability with the glass transition temperature of FAn reaching 207 °C and the thermal decomposition temperature as high as 439 ° C. The good performance of the fluorescent emitters makes them promising candidates as solution-processed blue organic light-emitting diodes.%合成了两类分别基于芘和蒽封端的芴-芳胺衍生物(FAn, FPy)的新型可溶液加工蓝色发光分子,两种材料均溶于常规的有机溶剂,并且可以旋涂成膜.通过紫外-可见光谱和荧光光谱对其在溶液中和固态薄膜下的光学性能进行了表征,发现这两类分子在固态下发射峰分别位于449和465 nm,属于蓝色发光材料.并通过循环伏安法表征了其电化学性能,计算得出FAn和FPy的最高占据分子轨道(HOMO)能级分别为-5.37和-5.36 eV.结果表明N-己基二苯胺

  2. Tumor initiating activities of various derivatives of benz(a)anthracene and 7, 12-dimethyl-benz(a)anthracene in mouse skin

    Energy Technology Data Exchange (ETDEWEB)

    Slaga, T.J.; Gleason, G.L.; DiGiovanni, J.; Berry, D.L.; Juchau, M.R.; Harvey, R.G.

    1978-01-01

    Current information indicates that polycyclic aromatic hydrocarbons (PAH) exert their toxic, mutagenic, and carcinogenic activities after they have been metabolically activated by target cells to reactive epoxides. The results obtained from IN VIVO and IN VITRO binding, mutagenicity, metabolism, and carcinogenicity studies have led to the conclusion that BP-7, 8-diol is a proximate carcinogenic metabolite of BP, and the BP-diol-epoxide is an ultimate carcinogenic metabolite of BP. Recent results concerning the strong carcinogenicity of BP-7..beta.., 8..cap alpha..-diol-9..cap alpha..,10..cap alpha..-epoxide in newborn mice and in mouse skin strongly indicate that it is the ultimate carcinogenic metabolite of BP. Since diol-epoxides may be responsible for the carcinogenicity of PAH other than BP, diols and diol-epoxides as well as other derivatives of PAH were tested for skin tumor-initiation in a two-stage system of tumorigenesis. In addition, since activation of methylated PAH may involve the side-chain methyl group, the skin tumor-initiating activity of various side-chain derivatives of methylated PA were determined. In this report, the skin tumor initiation of various derivatives of a nonmethylated PAH, BA as well as a methylated PAH, DMBA are compared. The data suggest that bay region diol-epoxides may be important in BA and DMBA carcinogenicity in mice which is supportive of the theory proposed by Jerina and co-workers which predicts that diol-epoxides in the bay region are the major determinants of PAH carcinogenicity.

  3. Preparation, characterization, physical properties, and photoconducting behaviour of anthracene derivative nanowires

    Science.gov (United States)

    Xiao, Jinchong; Yin, Zongyou; Yang, Bo; Liu, Yi; Ji, Li; Guo, Jun; Huang, Ling; Liu, Xuewei; Yan, Qingyu; Zhang, Hua; Zhang, Qichun

    2011-11-01

    Organic nanowires of 9,10-dibromoanthracene (DBA) and 9,10-dicyanoanthracene (DCNA) were obtained by adding the THF solution of DBA/DCNA into water containing P123 surfactants. The as-prepared nanowires were characterized by UV-vis, fluorescence spectra, Field Emission Scanning Electron Microscopy (FESEM), and Transmission Electron Microscopy (TEM). We found that DBA and DCNA nanowires emitted green light rather than blue light for molecules in THF solution. The red-shift UV and fluorescent spectra of DBA and DCNA nanowires implied that these nanowires were formed through J-aggregation. The photoconducting study of DBA/DCNA nanowire-based network on rGO/SiO2/Si shows different photocurrent behaviors upon irradiation, which displayed that electron transfer from DCNA nanowire to rGO was stronger than that of DBA nanowires to rGO.Organic nanowires of 9,10-dibromoanthracene (DBA) and 9,10-dicyanoanthracene (DCNA) were obtained by adding the THF solution of DBA/DCNA into water containing P123 surfactants. The as-prepared nanowires were characterized by UV-vis, fluorescence spectra, Field Emission Scanning Electron Microscopy (FESEM), and Transmission Electron Microscopy (TEM). We found that DBA and DCNA nanowires emitted green light rather than blue light for molecules in THF solution. The red-shift UV and fluorescent spectra of DBA and DCNA nanowires implied that these nanowires were formed through J-aggregation. The photoconducting study of DBA/DCNA nanowire-based network on rGO/SiO2/Si shows different photocurrent behaviors upon irradiation, which displayed that electron transfer from DCNA nanowire to rGO was stronger than that of DBA nanowires to rGO. Electronic supplementary information (ESI) available: XRD patterns and simulations, and FT-IR spectra. CCDC reference numbers 840471. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c1nr10655d

  4. Interlayer Energy Transfer from Naphthalene to Anthracene Chromophores Organized in Langmuir—Blodgett Films

    Institute of Scientific and Technical Information of China (English)

    LiQianLI; ChiMingCHE; 等

    2002-01-01

    Interlayer energy transfer between 2,3-naphthol-10-hexadecylaza-15-crown-5(NC16) and N-[1-(9-methoxyanthryl)] decylaza-15-crown-5(A10C) within multilayer Langmuir-Blodgett films has been studied by steady-state fluorescence spectra. The donor and acceptor could be separated precisely by inserting stearic acid (SA) spacers. The efficiency of the energy transfer increases with the decrease in the donor-acceptor distance by a quadratic manner, suggesting the donor excitations are delocalized in the layer.

  5. Interlayer Energy Transfer from Naphthalene to Anthracene Chromophores Organized in Langmuir-Blodgett Films

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Interlayer energy transfer between 2, 3-naphtho-10-hexadecylaza-15-crown-5 (NC16) and N-[1-(9-methoxyanthryl)]decylaza-15-crown-5 (A10C) within multilayer Langmuir-Blodgett films has been studied by steady-state fluorescence spectra. The donor and acceptor could be separated precisely by inserting stearic acid (SA) spacers. The efficiency of the energy transfer increases with the decrease in the donor-acceptor distance by a quadratic manner, suggesting the donor excitations are delocalized in the layer.

  6. Studying the effect of high pressure on the cycloaddition reactions of maleic anhydride and substituted anthracenes

    Science.gov (United States)

    Kiselev, V. D.; Shakirova, I. I.; Kornilov, D. A.; Kashaeva, E. A.; Potapova, L. N.; Konovalov, A. I.

    2013-01-01

    The kinetics (rate, activation, and volume) of the high-pressure (up to 2500 bar) Diels-Alder reactions of maleic anhydride with 9-phenylanthracene and 9,10-dimethylanthracene in toluene is investigated.

  7. Functionalization of anthracene: A selective route to brominated 1,4-anthraquinones

    OpenAIRE

    Kiymet Berkil Akar; Osman Cakmak; Orhan Büyükgüngör; Ertan Sahin

    2011-01-01

    Efficient and stereoselective syntheses are described for the preparation of 2,3,9,10-tetrabromo-1,4-dimethoxy-1,2,3,4-tetrahydroanthracenes 7, 8 and the corresponding 1,4-diol 17 by silver ion-assisted solvolysis of hexabromotetrahydroanthracene 6. Base-promoted aromatization of 7 and 8 afforded synthetically valuable tribromo-1-methoxyanthracenes 10 and 11. The reaction of 17 with sodium methoxide generated tribromodihydroanthracene-1,4-diol 27, whose oxidation with PCC gave 2,9,10-tribromo...

  8. TELOMERASE ACTIVITY DURING 7, 12-DIMETHYLBENZ [a] ANTHRACENE-INDUCED HAMSTER BUCCAL POUCH CARCINOGENESIS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To investigate the roles of telomerase activity (TA) in relation to hamster buccal pouch tumor progression. Methods: male hamster were treated three times weekly with 0.5% of 7, 12-dimethyl- benzanthracene (DMBA) over a 15 weeks experimental period. Hamsters were sacrificed at 3, 6, 9, 12 and 15 weeks after treatment. Telomerase activity of hamster buccal pouch tissue were measured along with the analyses of the formation of DMBA-induced hamster buccal pouch tumors. Results: DMBA-induced squamous cell carcinomas were found at the 6th week after dosing. Telomerase activity elevation began at the 3rd week and was increasing to a plateau at the 12th week. Conclusion: Our results show that telomerase activity in the target tissue may be detected at the early stage of the DMBA-induced hamster buccal pouch tumor formation and suggests that telomerase activity may be used as a biomarker for an early clinical detection of buccal pouch cancer.

  9. Decreased adrenal medullary tyrosine hydroxylase mRNA in DMBA (7,12-dimethylbenz(a)anthracene)-induced mammary carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Bunce, O.R.; Badary, O.A.; Abou El-Ela, S.; Hartle, D.K. (Univ. of Georgia, Athens (United States))

    1991-03-15

    Adrenal cortical hormones suppress initiation and promotion of DMBA-induced mammary tumorigenesis. The authors found a positive correlation between presence of DMBA-induced adrenal cortical necrosis and mammary tumor incidence. Because they find adrenal medullary as well as cortical lesions in tumor bearing (TB) DMBA-treated rats, they evaluated medullary function by quantitating hybridized cDNA- TH-S{sup 35} with in situ TH-mRNA u sing computer assisted quantitative autoradiographic technique. Virgin female Sprague-Dawley rats were given a 10 mg i.g. dose of DMBA. Three wks later, rats were placed on 20% polyunsaturated (PUFA) fat diets containing omega-6 and omega-3 fatty acids. All were killed 15 wks post-DMBA. TH-mRNA levels in adrenal medullae of TB animals were decreased compared to non-TB rats. Histopathology indicated a high incidence of medullary necrosis in TB rats, whereas, adrenal necrosis did not occur in non-TB animals. Adrenal necrosis correlated positively with tumor burden, but no correlation was found between incidence of adrenal lesions and type of PUFA in the diet. The authors suggest that DMBA adrenal necrosis may reduce TH-mRNA in the medulla, compromise its catecholamine synthetic capability, and thereby contribute to the overall metabolic stress condition of TB rats.

  10. JWA deficiency suppresses dimethylbenz[a]anthracene-phorbol ester induced skin papillomas via inactivation of MAPK pathway in mice.

    Directory of Open Access Journals (Sweden)

    Zhenghua Gong

    Full Text Available Our previous studies indicated that JWA plays an important role in DNA damage repair, cell migration, and regulation of MAPKs. In this study, we investigated the role of JWA in chemical carcinogenesis using conditional JWA knockout (JWA(Δ2/Δ2 mice and two-stage model of skin carcinogenesis. Our results indicated that JWA(Δ2/Δ2 mice were resistant to the development of skin papillomas initiated by 7, 12-dimethylbenz(aanthracene (DMBA followed by promotion with 12-O-tetradecanoylphorbol-13-acetate (TPA. In JWA(Δ2/Δ2 mice, the induction of papilloma was delayed, and the tumor number and size were reduced. In primary keratinocytes from JWA(Δ2/Δ2 mice, DMBA exposure induced more intensive DNA damage, while TPA-promoted cell proliferation was reduced. The further mechanistic studies showed that JWA deficiency blocked TPA-induced activation of MAPKs and its downstream transcription factor Elk1 both in vitro and in vivo. JWA(Δ2/Δ2 mice are resistance to tumorigenesis induced by DMBA/TPA probably through inhibition of transcription factor Elk1 via MAPKs. These results highlight the importance of JWA in skin homeostasis and in the process of skin tumor development.

  11. Bromelain nanoparticles protect against 7,12-dimethylbenz[a]anthracene induced skin carcinogenesis in mouse model.

    Science.gov (United States)

    Bhatnagar, Priyanka; Pant, Aditya B; Shukla, Yogeshwer; Chaudhari, Bhushan; Kumar, Pradeep; Gupta, Kailash C

    2015-04-01

    Conventional cancer chemotherapy leads to severe side effects, which limits its use. Nanoparticles (NPs) based delivery systems offer an effective alternative. Several evidences highlight the importance of Bromelain (BL), a proteolytic enzyme, as an anti-tumor agent which however has been limited due to the requirement of high doses at the tumor site. Therefore, we illustrate the development of BL loaded poly (lactic-co-glycolic acid) NPs that show enhanced anti-tumor effects compared to free BL. The formulated NPs with a mean particle size of 130.4 ± 8.81 nm exhibited sustained release of BL. Subsequent investigation revealed enhanced anti-tumor ability of NPs in 2-stage skin tumorigenesis mice model. Reduction in average number of tumors (∼ 2.3 folds), delay in tumorigenesis (∼ 2 weeks), percent tumorigenesis (∼ 4 folds), and percent mortality rate as well as a reduction in the average tumor volume (∼ 2.5 folds) in mice as compared to free BL were observed. The NPs were found to be superior in exerting chemopreventive effects over chemotherapeutic effects at 10 fold reduced dose than free BL, validated by the enhanced ability of NPs (∼ 1.8 folds) to protect the DNA from induced damage. The effects were also supported by histopathological evaluations. NPs were also capable of modulating the expression of pro-apoptotic (P53, Bax) and anti-apoptotic (Bcl2) proteins. Therefore, our findings demonstrate that developed NPs formulation could be used to improve the efficacy of chemotherapy by exerting chemo-preventive effects against induced carcinogenesis at lower dosages. PMID:25619920

  12. Inclusion of an Anthracene-based Fluorophore within Molecular Containers: A Comparative Study of the Cucurbituril and Cyclodextrin Host Families.

    Science.gov (United States)

    Ganguly, Aniruddha; Ghosh, Soumen; Guchhait, Nikhil

    2016-05-19

    In this paper, the binding interaction of a promising chloride channel blocker, 9-methyl anthroate (9-MA), with two different classes of molecular containers, β-cyclodextrins (β-CD and methyl-β-CD) and cucurbit[7]uril, having comparable cavity dimensions, has been thoroughly demonstrated via inspection of the modulation of the excited-state properties of the emissive molecule. Spectral data suggest that CB7 encapsulates the probe more efficiently in a 1:2 fashion, whereas the efficacies of β-CDs are relatively less and the corresponding stoichiometry is 1:1. Interestingly, despite being thermodynamically much more favorable than the probe-β-CD complexation equilibria, the fraction of probe-CB7 complex formed is appreciably smaller with respect to that of probe-β-CD complexes. This apparent inconsistency has been addressed via the proposition that since the formation of a 1:2 complex is entropically disadvantageous, it is anticipated that the activation barrier of the corresponding reaction is reasonably high, and thus only a small fraction of the reactants are able to surpass the energy barrier to form the products. This proposition has been thoroughly corroborated by fluorescence lifetime measurements at different temperatures. PMID:27119387

  13. Fluorogenic probes for chemical transformations: 9-anthracene derivatives for monitoring reaction progress by an increase in fluorescence

    OpenAIRE

    Mase, Nobuyuki; Takabe, Kunihiko; Tanaka, Fujie

    2013-01-01

    NOTICE: this is the author’s version of a work that was accepted for publication in Tetrahedron Letters.Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document.Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in PUBLICATION, Volume 54, Issue 32, 7 August 2013. DOI10.1016/j.tetlet.2013....

  14. Inhibition of murine splenic B lymphocyte activation following oral exposure to 7,12-dimethylbenz(a)anthracene (DMBA)

    International Nuclear Information System (INIS)

    Previous results from this laboratory have demonstrated that oral exposure of B6C3F1 mice to DMBA inhibited mitogen-stimulated lymphocyte activation in cells recovered from several lymphoid organs. These studies showed that both LPS and PHA-stimulated lymphocyte proliferation and PHA-induced Ca+2 mobilization were significantly inhibited by DMBA exposure, supporting the hypothesis that DMBA inhibits early events associated with lymphocyte activation. The purpose of the current studies was to test this hypothesis directly for B cell activation. B6C3F1 mice were treated with 0, 1.0, or 10 mg/kg/day doses of DMBA for 14 days (total cumulative doses of 0, 14, or 140 mg/kg). B lymphocyte populations were then selected on the flow cytometer by direct positive staining of spleen cells with phycoerythrin-labeled anti-Ly5 (B lymphocyte marker) antibodies. Ca+2 mobilization studies were performed using affinity-purified goat anti-mouse IgD antibodies as the stimulant and Indo-1 as the intracellular Ca+2 indicator. Cell proliferation studies were also performed using 3H-thymidine and insoluble anti-IgD antibodies. Anti-IgD stimulated Ca+2 mobilization was significantly reduced at the 140 mg/kg dose of DMBA. A statistically significant decrease in anti-IgD stimulated B lymphocyte proliferation at the 14 mg/kg and 140 mg/kg doses of DMBA was found. These results suggest that B lymphocytes may be important targets for DMBA-mediated immunosuppression

  15. A Systematic Study of the Effects of Naphthalene and Anthracene Substitution on the Properties of PPV Derivative Conjugated Systems

    OpenAIRE

    Lynch, Patrick; O'Neill, Luke; Bradley, David; Byrne, Hugh; McNamara, Mary

    2007-01-01

    The systematic synthesis of poly(phenylvinylene) (PPV) derivatives by the Wittig-Horner reaction is reported. The phenyl units of the PPV structure are methodically substituted by naphthyl and anthryl units to form a homologous series of structures. The 2,6 attachment of the vinylene linkage on the anthryl ring provides novel structures that have not been reported before due to their synthetic inaccessibility. The introduction of naphthyl units results in a hypsochromatic shift in the absorpt...

  16. Highly red-shifted NIR emission from a novel anthracene conjugated polymer backbone containing Pt( ii ) porphyrins

    KAUST Repository

    Freeman, D. M. E.

    2015-11-30

    © The Royal Society of Chemistry 2016. We present the synthesis of a novel diphenylanthracene (DPA) based semiconducting polymer. The polymer is solubilised by alkoxy groups attached directly to a DPA monomer, meaning the choice of co-monomer is not limited to exclusively highly solubilising moieties. Interestingly, the polymer shows a red-shifted elecroluminescence maximum (510 nm) when compared to its photoluminescence maximum (450 nm) which we attribute to excimer formation. The novel polymer was utilised as a host for a covalently-linked platinum(ii) complexed porphyrin dopant. Emission from these polymers was observed in the NIR and again showed almost a 100 nm red shift from photoluminescence to electroluminescence. This work demonstrates that utilising highly aggregating host materials is an effective tool for inducing red-shifted emission in OLEDs.

  17. 低浓度蒽对两种海洋微藻生长的兴奋效应%Stimulation effect of anthracene on marine microalgae growth

    Institute of Scientific and Technical Information of China (English)

    王悠; 唐学玺; 李永祺; 刘泳

    2002-01-01

    以两种海洋微藻金藻8701(Isochrysis galbana 8701)和骨条藻(Skeletonema costatum)为材料,研究了低浓度蒽(1.5~6μg*L-1)对两种海洋微藻生长的影响.结果表明,在一定浓度蒽作用下,两种微藻的生长均呈现出较明显的"兴奋效应",细胞密度有所增加,但达到最佳刺激作用的浓度与时间有所不同.在刺激浓度作用下,两种微藻体内的蛋白质、叶绿素a(chla.)、类胡萝卜素(car.)含量都有所增加,其变化趋势与细胞密度的变化类似.在整个实验过程中,微藻体内清除活性氧的关键性酶超氧化物歧化酶(SOD)始终处于较高水平,其变化趋势类似于细胞密度的变化.

  18. Morphological changes in the lingual papillae and their connective tissue cores on the 7,12-dimethylbenz[alpha]anthracene (DMBA) stimulated rat experimental model.

    Science.gov (United States)

    Zheng, Jinhua; Xie, Liping; Teng, He; Liu, Shilong; Yoshimura, Ken; Kageyama, Ikuo; Kobayashi, Kan

    2009-02-01

    The aim of the study was to analyze morphological changes of the epithelial surface and underlying connective tissue cores (CTCs) of the lingual mucosa in the rat using a DMBA induced pre-cancerous experimental model. Lightmicroscopically, initially DMBA treated sections exhibited infiltration of chronic inflammatory cells. At 16 weeks, aldehyde-fuchsin (AF) positive elastic fibers decreased and were scanty in the juxtaepithelium. On the other hand, rather densely packed thick bundles of AF positive fibers were observable in the deep layers of lamina propria. Carcinomas were not found at any stage, however, epithelial dysplasia was observed at 24 weeks post-treatment with DMBA. Scanning electron microscopy revealed an irregular arrangement of filiform papillae 4-12 weeks following DMBA stimulation. Patchy degenerated areas were observed especially at 16-24 weeks post-treatment and filiform papillae were totally attenuated on the central part of the degenerated areas. After removal of the epithelium, attenuated CTCs were observed from 4-8 weeks. Morphology of CTCs seemed to be gradually remodeled and severely altered in the later stage. The CTCs were however attenuated and exhibited a patchy distribution. The animal experimental model in this study revealed degenerative morphological changes of CTCs of the lingual papillae in the precancerous stage induced by DMBA.

  19. Synthesis and Crystal Structure of Calix[4]arene Bearing a 1,8-Bis(propoxy)anthracene-9,10-dione

    Institute of Scientific and Technical Information of China (English)

    GU Shao-Jin; QIN Da-Bin; JIN Lin-Hai

    2008-01-01

    The title complex (C50 H44Cl4O8) was synthesized and structurally determined by single-crystal X-ray diffraction method.It crystallizes in monoclinic, space group P21/n with a = 19.7768(4), b =10.2085(2), c = 21.2721(4) A, β = 97.153(1)°, V = 4261.23(14) A3, Z = 4, Mr = 914.65, F(000) = 1904, Dc = 1.426 g/cm3, μ = 0.336, the final R = 0.0550 and wR = 0.1647.The compound was structurally characterized by IR and 1H NMR.The molecules are stacked through C-H…π interactions and intermolecular C-H…O hydrogen bonds.

  20. Dietary effects of soy isoflavones daidzein and genistein on 7,12-dimethylbenz[a]anthracene-induced mammary mutagenesis and carcinogenesis in ovariectomized Big Blue transgenic rats.

    OpenAIRE

    Manjanatha, Mugimane; Shelton, Sharon; Bishop, Michelle; Lyn-Cook, Lascelles; Aidoo, Anane

    2006-01-01

    Dietary modulation of cancer & cancer biomarkers. Dietary item or component studied: the isoflavones daidzein (DZ) and genistein (GE)Outcome studied: Mammary gland hyperplasia; DNA damage. Study type: Big Blue transgenic rats Tissue/biological material/sample size: mammary glands; lymphocytes isolated from the spleen. Mode of exposure: dietary. Impact on outcome (including dose-response): The isoflavones or E(2) supplementation alone resulted in the lac I MFs that were not significantly diff...

  1. Determination of the Residual Anthracene Concentration in Cultures of Haloalkalitolerant Actinomycetes by Excitation Fluorescence, Emission Fluorescence, and Synchronous Fluorescence: Comparative Study

    OpenAIRE

    Reyna del Carmen Lara-Severino; Miguel Ángel Camacho-López; Jessica Marlene García-Macedo; Gómez-Oliván, Leobardo M.; Sandoval-Trujillo, Ángel H.; Keila Isaac-Olive; Ninfa Ramírez-Durán

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are compounds that can be quantified by fluorescence due to their high quantum yield. Haloalkalitolerant bacteria tolerate wide concentration ranges of NaCl and pH. They are potentially useful in the PAHs bioremediation of saline environments. However, it is known that salinity of the sample affects fluorescence signal regardless of the method. The objective of this work was to carry out a comparative study based on the sensitivity, linearity, and detec...

  2. Pineal gland in rats with 7,12-dimethylbenz (a) anthracene-induced mammary tumors subjected to manipulations known as enhancers of pineal actions

    OpenAIRE

    Cos, S.; Bardasano, J. L.; Mediavilla, M D; Sánchez Barceló, E. J.

    1989-01-01

    The ultrastructure of pinealocytes was studied in rats with 7,17-dimethylbenz (a) anthraceneinduced manimary tumors which were subjected to experimental manipulations known as enhancers of pineal actions (anosmia, underfeeding or cold exposure). In these aniinals we found: (1) - more nuclei with deep nuclear invaginations; (11) - a large number of cytoplasmic organelles, including lipid droplets. myeloid bodies, synaptic ribbons and lysosomes; (111) - numer...

  3. Ground and excited state behavior of 1,4-dimethoxy-3-methyl-anthracene-9,10-dione in silver nanoparticles: Spectral and computational investigations

    Energy Technology Data Exchange (ETDEWEB)

    Umadevi, M., E-mail: ums10@yahoo.com [Department of Physics, Mother Teresa Women' s University, Kodaikanal 624101, Tamil Nadu (India); Kavitha, S.R. [Department of Physics, Mother Teresa Women' s University, Kodaikanal 624101, Tamil Nadu (India); Vanelle, P.; Terme, T.; Khoumeri, O. [Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, Aix-Marseille Univ, CNRS, Institut de Chimie Radicalaire ICR, UMR 7273, 27 Boulevard Jean Moulin, 13385 Marseille Cedex 05 (France)

    2013-10-15

    Silver nanoparticles (Ag NPs) of various sizes have been successfully synthesized by the simple and convenient Creighton method using sodium borohydride as the reducing agent under microwave irradiation. Optical absorption and fluorescence emission spectroscopic techniques were employed to investigate the effect of silver nanoparticles on the ground and excited state of 1,4-dimethoxy-3-methylanthracene-9,10-dione (DMMAD). The surface plasmon resonance (SPR) peak of the prepared silver colloidal solution was observed at 400 nm. Fluorescence quenching of DMMAD by silver nanoparticles has been found to increase with increase in the size of Ag. The fluorescence quenching has been explained by Forster Resonance Energy Transfer (FRET) theory between DMMAD and silver nanoparticles. The Stern–Volmer quenching constant and Benesi–Hildebrand association constant for the above system were calculated. DFT calculations were also performed to study the charge distribution of DMMAD in Ag both in ground and excited states. -- Highlights: • Silver nanoparticles (Ag NPs) have been synthesized using the Creighton method. • Effect of Ag NPs on the ground state of DMMAD was studied. • Influence of Ag NPs on the excited state of DMMAD was investigated. • Fluorescence quenching has been explained by Forster Resonance Energy Transfer. • Quenching and binding constants were also calculated.

  4. Protective effect of Ocimum sanctum on 3-methylcholanthrene, 7,12-dimethylbenz(a)anthracene and aflatoxin B1 induced skin tumorigenesis in mice

    International Nuclear Information System (INIS)

    A study on the protective effect of alcoholic extract of the leaves of Ocimum sanctum on 3-mthylcholanthrene (MCA), 7,12-dimethylbenzanthracene (DMBA) and aflatoxin B1 (AFB1) induced skin tumorigenesis in a mouse model has been investigated. The study involved pretreatment of mice with the leaf extract prior to either MCA application or tetradecanoyl phorbol acetate (TPA) treatment in a two-stage tumor protocol viz a viz, DMBA/TPA and AFB1/TPA. The results of the present study indicate that the pretreatment with alcoholic extract of the leaves of O. sanctum decreased the number of tumors in MCA, DMBA/TPA and AFB1/TPA treated mice. The skin tumor induced animals pretreated with alcoholic extract led to a decrease in the expression of cutaneous γ-glutamyl transpeptidase (GGT) and glutathione-S-transferase-P (GST-P) protein. The histopathological examination of skin tumors treated with leaf extract showed increased infiltration of polymorphonuclear, mononuclear and lymphocytic cells, decreased ornithine decarboxylase activity with concomitant enhancement of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the serum, implying the in vivo antiproliferative and immunomodulatory activity of leaf extract. The decrease in cutaneous phase I enzymes and elevation of phase II enzymes in response to topical application of leaf extract prior to MCA, AFB1, DMBA/TPA and AFB1/TPA treatment indicate the possibility of impairment in reactive metabolite(s) formation and thereby reducing skin carcinogenicity. Furthermore, pretreatment of leaf extract in the carcinogen induced animals resulted in elevation of glutathione levels and decrease in lipid peroxidation along with heat shock protein expression, indicating a scavenging or antioxidant potential of the extract during chemical carcinogenesis. Thus it can be concluded that leaf extract of O. sanctum provides protection against chemical carcinogenesis in one or more of the following mechanisms: (i) by acting as an antioxidant; (ii) by modulating phase I and II enzymes; (iii) by exhibiting antiproliferative activity

  5. Metabolism of benzo(a)pyrene and 7,12-dimethylbenz(a)anthracene in cultured human bronchus and pancreatic duct

    DEFF Research Database (Denmark)

    1977-01-01

    patients with lung cancer were also compared with those from patients without lung cancer. The profiles were similar except for an observed higher percentage of organic solvent-extractable metabolites formed by bronchi from the noncancer patients that eluted from the column as a single peak. This peak...

  6. Luteolin suppresses development of medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Sprague-Dawley rats.

    Science.gov (United States)

    Cook, Matthew T; Mafuvadze, Benford; Besch-Williford, Cynthia; Ellersieck, Mark R; Goyette, Sandy; Hyder, Salman M

    2016-02-01

    Postmenopausal women undergoing hormone-replacement therapy containing both progestins and estrogens are at an increased risk of developing breast cancer compared with women taking estrogen alone. We recently demonstrated that medroxyprogesterone acetate, a progestin commonly used for hormone-replacement therapy, accelerates development of mammary carcinogenesis in 7,12-dimethylbenz(a)anthracene‑treated Sprague-Dawley rats. Synthetic antiprogestins used to block the deleterious effects of progestins, are themselves associated with toxic side-effects. In order to circumvent this, we used the aforementioned model to identify less toxic natural compounds that may prevent the development of progestin-accelerated tumors. Luteolin, a naturally-occurring flavonoid commonly found in fruits and vegetables, has previously been shown to possess anticancer properties. In our studies, both low (1 mg/kg) and high (25 mg/kg) doses of luteolin significantly suppressed progestin-dependent increases in tumor incidence, while increasing tumor latency and reducing the occurrence of large (>300 mm3) mammary tumors. However, an intermediate dose of luteolin (10 mg/kg), while suppressing the development of large tumors, did not affect either tumor incidence or latency. Immunohistochemical analysis of tumor tissues revealed that all concentrations of luteolin (1, 10, and 25 mg/kg) significantly reduced levels of VEGF within tumors. The suppressive effects of luteolin on tumor incidence and volume, together with its ability to reduce VEGF and blood vessels, persisted even after treatment was terminated. This suggests that luteolin possesses anti‑angiogenic properties which could mechanistically explain its capacity to control tumor progression. Thus luteolin may be a valuable, non-toxic, naturally-occurring anticancer compound which may potentially be used to combat progestin-accelerated mammary tumors. PMID:26719029

  7. 40 CFR Appendix II to Part 258 - List of Hazardous Inorganic and Organic Constituents

    Science.gov (United States)

    2010-07-01

    ...-Aminobiphenyl 92-67-1 -4-amine Anthracene 120-12-7 Anthracene Antimony (Total) Antimony Arsenic (Total) Arsenic..., ethyl- Ethyl methacrylate 97-63-2 2-Propenoic acid, 2-methyl-, ethyl ester Ethyl methanesulfonate...

  8. Determination of the effective redox potentials of SmI₂, SmBr₂, SmCl₂, and their complexes with water by reduction of aromatic hydrocarbons. Reduction of anthracene and stilbene by samarium(II) iodide-water complex.

    Science.gov (United States)

    Szostak, Michal; Spain, Malcolm; Procter, David J

    2014-03-21

    Samarium(II) iodide-water complexes are ideally suited to mediate challenging electron transfer reactions, yet the effective redox potential of these powerful reductants has not been determined. Herein, we report an examination of the reactivity of SmI2(H2O)n with a series of unsaturated hydrocarbons and alkyl halides with reduction potentials ranging from -1.6 to -3.4 V vs SCE. We found that SmI2(H2O)n reacts with substrates that have reduction potentials more positive than -2.21 V vs SCE, which is much higher than the thermodynamic redox potential of SmI2(H2O)n determined by electrochemical methods (up to -1.3 V vs SCE). Determination of the effective redox potential demonstrates that coordination of water to SmI2 increases the effective reducing power of Sm(II) by more than 0.4 V. We demonstrate that complexes of SmI2(H2O)n arising from the addition of large amounts of H2O (500 equiv) are much less reactive toward reduction of aromatic hydrocarbons than complexes of SmI2(H2O)n prepared using 50 equiv of H2O. We also report that SmI2(H2O)n cleanly mediates Birch reductions of substrates bearing at least two aromatic rings in excellent yields, at room temperature, under very mild reaction conditions, and with selectivity that is not attainable by other single electron transfer reductants.

  9. Design and Rehabilitation for Oxidization Column of Hydrogen Peroxide Using Anthracene and Quinine Process%蒽醌法生产过氧化氢工艺中氧化塔的设计与改造

    Institute of Scientific and Technical Information of China (English)

    施友立

    2006-01-01

    通过对当前过氧化氢生产装置氧化塔氧化收率偏低的各种因素进行分析,找出影响氧化收率的关键因素,并提出氧化塔设计或改造的方向.并列举该类塔的改造效果.

  10. Prenatal 3,3',4,4',5-pentachlorobiphenyl exposure modulates induction of rat hepatic CYP 1A1, 1B1, and AhR by 7,12-dimethylbenz[a]anthracene

    International Nuclear Information System (INIS)

    We previously reported the finding that prenatal exposure to a relatively low dose of PCB126 increases the rate of DMBA-induced rat mammary carcinoma, while a high dose decreased it. One of the most important factors determining the sensitivity to mammary carcinogenesis is the metabolic stage at administration of the carcinogenic agent. DMBA is a procarcinogen that recruits the host metabolism to yield its ultimate carcinogenic form, and CYP1A1 and CYP1B1 (CYP1) conduct this metabolism. We investigated the hepatic expression of CYP1 and AhR following oral administration of DMBA (100 mg/kg b.w.) (i.g.) to 50-day-old female Sprague-Dawley rats whose dams had been treated (i.g.) with 2.5 ng, 250 ng, 7.5 μg of PCB126/kg or the vehicle on days 13 to 19 post-conception. Real-time quantitative RT-PCR analysis revealed that the prenatal exposure to a relatively low dose of PCB126 (the 250 ng group) prolonged the higher expression of CYP1A1, CYP1B1, and AhR mRNA, while prenatal exposure to a high dose of PCB126 (the 7.5 μg group) prolonged the higher expression of CYP1A1 and AhR mRNA. Western blotting and immunohistochemical analyses were consistent with mRNAs changes. Because DMBA oxidation produces a highly mutagenic metabolite and is finally catalyzed by CYP1B1, a relatively low PCB126 dose might produce the biological character to potentially increase the risk of DMBA-induced mammary carcinoma

  11. Aggregation enhanced emission (AEE) in organic salt: A structure-property correlation based on single crystal studies

    Indian Academy of Sciences (India)

    Uttam Kumar Das; Parthasarathi Dastidar

    2014-09-01

    Salt formation has been shown as a simple strategy to induce aggregated induced emission or aggregated enhanced emission in primary ammonium salts derived from 9-anthracene carboxylic acid, 1-pyrene carboxylic acid, 3-coumarin carboxylic acid and histamine. All the salts displayed enhanced fluorescence in their solid state compared to that in their solution state. Single crystal structure of the salt of 9-anthracene carboxylic acid i.e., His-anthracene revealed that restricted intramolecular rotation of the fluorphoric moiety (anthracene) was responsible for such radiative pathway leading to enhanced emission.

  12. A molecular-sized tunnel-porous crystal with a ratchet gear structure and its one-way guest-molecule transportation property

    Science.gov (United States)

    Kataoka, Keisuke; Yasumoto, Tetsuaki; Manabe, Yousuke; Sato, Hiroyasu; Yamano, Akihito; Katagiri, Toshimasa

    2013-01-01

    An anisotropic tunnel microporous crystal was prepared. Active transportation of anthracene as a guest molecule in the anisotropic tunnels was observed. The direction of anthracene movement implies that the anisotropic tunnel did not work as a flap-check valve. The direction of the movement was consistent with that caused by a Brownian ratchet.An anisotropic tunnel microporous crystal was prepared. Active transportation of anthracene as a guest molecule in the anisotropic tunnels was observed. The direction of anthracene movement implies that the anisotropic tunnel did not work as a flap-check valve. The direction of the movement was consistent with that caused by a Brownian ratchet. Electronic supplementary information (ESI) available. CCDC reference numbers 837539 and 837540. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c2nr30880k

  13. Comments on Coulomb pairing in aromatic hydrocarbons

    CERN Document Server

    Huber, D L

    2013-01-01

    Recently reported anomalies in the double-photonionization spectra of aromatic molecules such as benzene, naphthalene, anthracene and coronene are attributed to Coulomb-pair resonances of pi electrons.

  14. Use of antioxidant enzymes of clam Ruditapes philippinarum as biomarker to polycyclic aromatic hydrocarbon pollution

    Science.gov (United States)

    Zhu, Lin; Tang, Xuexi; Wang, Ying; Sui, Yadong; Xiao, Hui

    2016-03-01

    The typical organic pollutant polycyclic aromatic hydrocarbon (PAH) anthracene was selected as a contaminant to investigate its effects on the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in the clam Ruditapes philippinarum. The results show that SOD, CAT and GSH-Px had diff erent induction and inhibition reactions to anthracene stress, and that three diff erent organs in R. philippinarum (visceral mass, muscle tissue and mantle) had diff erent sensitivities to anthracene stress. This study suggest that SOD activities of the visceral mass, CAT activitities of the mantle and the visceral mass, and GSH-Px activity of the muscle tissue could be used as sensitive indicators of anthracene stress in R. philippinarum.

  15. Downscaling the in vitro test of fungal bioremediation of polycyclic aromatic hydrocarbons: methodological approach.

    Science.gov (United States)

    Drevinskas, Tomas; Mickienė, Rūta; Maruška, Audrius; Stankevičius, Mantas; Tiso, Nicola; Mikašauskaitė, Jurgita; Ragažinskienė, Ona; Levišauskas, Donatas; Bartkuvienė, Violeta; Snieškienė, Vilija; Stankevičienė, Antanina; Polcaro, Chiara; Galli, Emanuela; Donati, Enrica; Tekorius, Tomas; Kornyšova, Olga; Kaškonienė, Vilma

    2016-02-01

    The miniaturization and optimization of a white rot fungal bioremediation experiment is described in this paper. The optimized procedure allows determination of the degradation kinetics of anthracene. The miniaturized procedure requires only 2.5 ml of culture medium. The experiment is more precise, robust, and better controlled comparing it to classical tests in flasks. Using this technique, different parts, i.e., the culture medium, the fungi, and the cotton seal, can be analyzed. A simple sample preparation speeds up the analytical process. Experiments performed show degradation of anthracene up to approximately 60% by Irpex lacteus and up to approximately 40% by Pleurotus ostreatus in 25 days. Bioremediation of anthracene by the consortium of I. lacteus and P. ostreatus shows the biodegradation of anthracene up to approximately 56% in 23 days. At the end of the experiment, the surface tension of culture medium decreased comparing it to the blank, indicating generation of surfactant compounds. PMID:26660875

  16. Interplay between singlet and triplet excited states in a conformationally locked donor–acceptor dyad

    KAUST Repository

    Filatov, Mikhail A.

    2015-10-13

    The synthesis and photophysical characterization of a palladium(II) porphyrin – anthracene dyad bridged via short and conformationally rigid bicyclo[2.2.2]octadiene spacer were achieved. A spectroscopic investigation of the prepared molecule in solution has been undertaken to study electronic energy transfer in excited singlet and triplet states between the anthracene and porphyrin units. By using steady-state and time-resolved photoluminescence spectroscopy it was shown that excitation of the singlet excited state of the anthracene leads to energy transfer to the lower-lying singlet state of porphyrin. Alternatively, excitation of the porphyrin followed by intersystem crossing to the triplet state leads to very fast energy transfer to the triplet state of anthracene. The rate of this energy transfer has been determined by transient absorption spectroscopy. Comparative studies of the dynamics of triplet excited states of the dyad and reference palladium octaethylporphyrin (PdOEP) have been performed.

  17. A novel portable system for detecting and measuring tritium

    Science.gov (United States)

    Barillari, Domenico

    2007-06-01

    A novel tritium detector configuration is described based on the anthracene scintillation method. Tritium-bearing samples are applied to a plate-bearing finely sublimed anthracene crystals and viewed in a field-able PMT-based reader against a standard plate. A microprocessor-based control and signal analysis system delivers a reading with a sensitivity of better than 5 nCi 3H in approximately 3 min, and 2.3 nCi in 10 min of counting.

  18. A fluorescent sensing membrane for iodine based on intramolecular excitation energy transfer of anthryl appended porphyrin

    Institute of Scientific and Technical Information of China (English)

    LONG LiPing; YOU MingXu; WANG Hao; WANG YongXiang; YANG RongHua

    2009-01-01

    A single anthryl appended meso-tetraphenylporphyrin (TPP) dyed has been synthesized and applied in fluorescence sensing of iodine based on the intramolecular excitation energy transfer. The molecular recognition of the sensor is based on the interaction of iodine with inner anthracene moiety of the dyad, while the signal reporter for the recognition process is the TPP fluorescence quenching. Because the emission spectrum of anthracene is largely overlapped with the Soret band absorption of TPP, in-tremolecular excitation energy transfer interaction occurs between the donor, anthracene and acceptor, TPP. This energy transfer leads to TPP fluorescence emission by excitation of anthracene. The sensor was constructed by immobilizing the dyad in a plasticized poly(vinyl chloride) (PVC) membrane. The sensing membrane shows higher sensitivity compared to the sensors by using anthracene, TPP, or a mixture of anthracene and TPP as sensing materials. Under the optimum conditions, iodine in a sample membrane shows satisfactory response characteristics including good reproducibility, reversibility end stability, as well as the short response time of less than 60 s. Except for Cr2O2-7 and MnO-4, other common metal ions and anions in foodstuff do not interfere with iodine determination. The proposed method was applied in the determination of iodine in table salt samples. The results agree well with those obtained by other methods.

  19. A fluorescent sensing membrane for iodine based on intramolecular excitation energy transfer of anthryl appended porphyrin

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A single anthryl appended meso-tetraphenylporphyrin (TPP) dyad has been synthesized and applied in fluorescence sensing of iodine based on the intramolecular excitation energy transfer. The molecular recognition of the sensor is based on the interaction of iodine with inner anthracene moiety of the dyad, while the signal reporter for the recognition process is the TPP fluorescence quenching. Because the emission spectrum of anthracene is largely overlapped with the Soret band absorption of TPP, intramolecular excitation energy transfer interaction occurs between the donor, anthracene and acceptor, TPP. This energy transfer leads to TPP fluorescence emission by excitation of anthracene. The sensor was constructed by immobilizing the dyad in a plasticized poly(vinyl chloride) (PVC) membrane. The sensing membrane shows higher sensitivity compared to the sensors by using anthracene, TPP, or a mixture of anthracene and TPP as sensing materials. Under the optimum conditions, iodine in a sample solution can be determined from 2.04 to 23.6 mmol·L-1 with a detection limit of 33 nmol·L-1. The sensing membrane shows satisfactory response characteristics including good reproducibility, reversibility and stability, as well as the short response time of less than 60 s. Except for Cr2O72- and MnO4-, other common metal ions and anions in foodstuff do not interfere with iodine determination. The proposed method was applied in the determination of iodine in table salt samples. The results agree well with those obtained by other methods.

  20. Determination of polycyclic aromatic hydrocarbons in smoked and non-smoked black teas and tea infusions.

    Science.gov (United States)

    Pincemaille, Justine; Schummer, Claude; Heinen, Eric; Moris, Gilbert

    2014-02-15

    This study describes the occurrence of polycyclic aromatic hydrocarbons (PAHs) in smoked tea and tea infusions, via the monitoring of benzo(a)anthracene, chrysene, benzo(b)fluoranthene and benzo(a)pyrene (PAH4) that have been chosen as indicators for the occurrence of PAHs in food by the European Food Safety Agency. The concentrations ranged from 1.2 μg/kg for benzo(b)fluoranthene to 125.0 μg/kg for benzo(a)anthracene in smoked tea leaves, and from 0.6 μg/L for benzo(a)anthracene to 1.2 μg/L for benzo(b)fluoranthene in smoked tea infusions. Benzo(a)pyrene was never detected in infusions. The concentrations in non-smoked tea leaves ranged from 0.6 μg/kg for benzo(a)anthracene to 10.8 μg/kg for benzo(b)fluoranthene. It was shown that the concentrations of benzo(a)anthracene and chrysene were higher in smoked tea than in non-smoked tea while no difference was observed for benzo(b)fluoranthene and benzo(a)pyrene. The concentrations of PAHs in tea infusions are low compared to other foodstuffs, but the migration rates from leaves into water are high (82-123%).

  1. (E-Methyl 3-(10-bromoanthracen-9-ylacrylate

    Directory of Open Access Journals (Sweden)

    Bernhard Bugenhagen

    2013-07-01

    Full Text Available In the title molecule, C18H13BrO2, the anthracene unit forms an angle of 46.91 (2° with the mean plane of the methyl acrylate moiety. In the crystal, the molecules arrange themselves into strands parallel to [010] and, due to the crystal symmetry, there are eight strands crossing the unit cell. In each strand, molecules form short C—H...O and C—H...π contacts and have their anthracene groups parallel to each other. Neighboring strands, related by a c-glide operation, are connected via C—H...O interactions and form a layer parallel to (100. The arrangement of the acrylate and anthracene groups in the crystal do not allow for [2 + 2] or [4 + 4] cycloaddition.

  2. A Shape-Persistent Cryptand for Capturing Polycyclic Aromatic Hydrocarbons.

    Science.gov (United States)

    Zhang, Rui-Feng; Hu, Wen-Jing; Liu, Yahu A; Zhao, Xiao-Li; Li, Jiu-Sheng; Jiang, Biao; Wen, Ke

    2016-07-01

    A shape-persistent cryptand 1, containing two face-to-face oriented electron-deficient 2,4,6-triphenyl-1,3,5-triazine units separated by approximately 7 Å, and bridged by two rigid 1,8-naphthyridine linkers and a pentaethylene oxide loop, is created for capturing polycyclic aromatic hydrocarbons. Cryptand 1 formed 1:1 complexes with PAH guest molecules, such as phenanthrene (6), anthracene (7), pyrene (8), triphenylene (9), and tetraphene (10). The single-crystal structure of complex 6⊂1 revealed that 6 was included in the cavity of 1 via face-to-face π···π stacking interactions. Soaking crystalline 1 in a toluene solution of anthracene resulted in anthracene from the toluene solution being picked up by the crystalline solid of 1. PMID:27258531

  3. Hydrogen Peroxide Production as a Limiting Factor in Xenobiotic Compound Oxidation by Nitrogen-Sufficient Cultures of Bjerkandera sp. Strain BOS55 Overproducing Peroxidases

    OpenAIRE

    Kotterman, M.; Wasseveld, R. A.; Field, J. A.

    1996-01-01

    The overproduction of ligninolytic peroxidase by the N-deregulated white rot fungus Bjerkandera sp. strain BOS55 under nitrogen-sufficient conditions had no noteworthy effect on the oxidation of anthracene or the decolorization of the polymeric aromatic dye Poly R-478 in 6-day-old cultures. Only when the endogenous production of H(inf2)O(inf2) was increased by the addition of extra oxygen and glucose could a 2.5-fold increase in the anthracene oxidation rate and a 6-fold increase in the Poly ...

  4. Application of singular value decomposition analysis to time-dependent powder diffraction data of an in-situ photodimerization reaction

    International Nuclear Information System (INIS)

    A successful application of singular value decomposition analysis to time-dependent powder diffraction data of an in-situ photodimerization reaction of some anthracene derivatives is presented. Singular value decomposition (SVD) analysis has important applications for time-dependent crystallographic data, extracting significant information. Herein, a successful application of SVD analysis of time-resolved powder diffraction data over the course of an in-situ photodimerization reaction of anthracene derivatives is introduced. SVD revealed significant results in the case of 9-methylanthracene and 1-chloroanthracene. The results support the formation of the 9-methylanthracene stable dimer phase and suggest the existence of an excimer state

  5. Monitoring the synthesis of new pitches from coal tar and its fractions by chromatography and related techniques.

    Science.gov (United States)

    Bermejo, J; Fernández, A L; Prada, V; Granda, M; Menéndez, R

    1999-07-23

    The aim of this paper is to study the applications of chromatography and related techniques in the transformation of coal-derived products into pitches for specific uses. Anthracene oil, tar and pitch were thermally treated in the presence of air (and sulfur in the case of anthracene oil) in order to cause the polymerization/condensation of their components. The evolution of the components of the parent materials during the treatments was monitored by gas chromatography-mass spectrometry, gas chromatography-atomic emission detection, probe mass spectrometry and size-exclusion chromatography. From the results obtained, possible mechanisms for the transformation of coal-derived products into new pitches were established.

  6. Triplet excitation dynamics of two keto-carotenoids in n-hexane and in methanol as studied by ns flash photolysis spectroscopy

    Science.gov (United States)

    Li, Li; Hu, Feng; Chang, Yu-Qiang; Zhou, Yan; Wang, Peng; Zhang, Jian-Ping

    2015-07-01

    Siphonaxanthin and siphonein are two keto-carotenoids. Upon anthracene-sensitizing, triplet excitation dynamics of these two carotenoids were studied in n-hexane and in methanol, respectively, by ns flash photolysis spectroscopy. In n-hexane, bleaching of the ground state absorption (GSB) and the excitation triplet (3Car*) absorption were observed. In methanol, upon the decay of the 3Car*, the cation dehydrodimer of carotenoid, #[Car]2+, generated by the same rate, while an additional GSB generated synchronously, a polar solvent assisted and anthracene-sensitized mechanism was addressed based on the discussion. The environment-sensitive triplet excitation dynamics imply their potential role in photo-protection in vivo.

  7. 40 CFR 464.11 - Specialized definitions.

    Science.gov (United States)

    2010-07-01

    .... tetrachloroethylene 87. trichloroethylene (2) Die Casting (§ 464.15(c) and § 464.16(c)): 1. acenaphthene 4. benzene 7.... chrysene 78. anthracene 80. fluorene 81. phenanthrene 84. pyrene 85. tetrachloroethylene 86. toluene (3... (2-ethylhexyl) phthalate 84. pyrene 85. tetrachloroethylene 87. trichloroethylene (5) Melting...

  8. A double-leg donor-acceptor molecular elevator: new insight into controlling the distance of two platforms.

    Science.gov (United States)

    Zhang, Zhi-Jun; Han, Min; Zhang, Heng-Yi; Liu, Yu

    2013-04-01

    A double-leg elevator with an electron-rich anthracene moiety at the platformlike component and an electron-deficient naphthalenediimide unit in the middle of a double-leg riglike component was prepared through "click chemistry", in which the reversible elevator movement between different levels could be controlled upon the addition of base and acid. PMID:23534551

  9. Physicochemical study on interactions between T-2 and HT-2 toxin derivatives and cyclodextrins

    Science.gov (United States)

    Physicochemical interactions occurring between fluorescent anthracene derivatives of T-2 and HT-2 toxins and different cyclodextrins (CDs) were investigated in aqueous solutions by means of UV-Vis absorption, fluorescence emission, and Dynamic Light Scattering. Binding constant values and physicoche...

  10. Phthalate and PAH concentrations in dust collected from Danish homes and daycare centers

    DEFF Research Database (Denmark)

    Langer, Sarka; Weschler, Charles J.; Fischer, Andreas;

    2010-01-01

    (diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), di(isobutyl) phthalate (DiBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP)) and three PAHs (pyrene, benz[a]anthracene (B[a]A) and benzo[a]pyrene (B[a]P)). The three PAHs and DEHP were detected in dust samples from all sites, while...

  11. 9-(Guanidinomethyl)-10-vinylanthracene: a suitable fluorescent monomer for MIPs

    NARCIS (Netherlands)

    Zhang, Huiqi; Verboom, Willem; Reinhoudt, David N.

    2001-01-01

    9-(Guanidinomethyl)anthracene derivatives with a bromo (6) or a vinyl group (10) at the 10-position have been prepared starting from 9-bromoanthracene (1). They show 1:1 complexation with carboxylic acids or carboxylates with K-values of 1.2–1.4×105 M−1 in deuteriomethanol. Copolymerization of 9-vin

  12. Self-assembly of diphenylalanine peptides into microtubes with "turn on" fluorescence using an aggregation-induced emission molecule.

    Science.gov (United States)

    Na, Na; Mu, Xiaoyan; Liu, Qiuling; Wen, Jiying; Wang, Fangfang; Ouyang, Jin

    2013-10-01

    The self-assembly of diphenylalanine peptides (l-Phe-l-Phe) into microtubes with "turn on" bright yellow green fluorescence was described, which was achieved using an aggregation-induced emission (AIE) molecule of 9,10-bis[4-(3-sulfonatopropoxyl)-styryl] anthracene (BSPSA) sodium. PMID:24045462

  13. Synthesis and Property of New Propeller Shaped Emitting Materials for Organic Light-Emitting Devices.

    Science.gov (United States)

    Kang, Seokwoo; Lee, Hayoon; Kim, Beomjin; Park, Youngil; Park, Jongwook

    2016-03-01

    New propeller type emitting compound, namely 3,6-di-anthracen-9-yl-9,10-bis-(4-anthracen-9-yi-phenyl)-phenanthrene[TAnDAP] and 3,6-bis-(10-phenyl-anthracen-9-yl)-9,10-bis-[4-(10-phenyl-anthracen-9-yl)-phenyl]-phenanthrene [TAnPDAP] were synthesized through Suzuki and McMurry reactions. We investigated their physical properties such as optical, electrochemical, and electroluminescent properties. The two compounds were used as an emitting layer in OLED devices: ITO/2-TNATA (60 nm)/NPB (15 nm)/non-doped: TAnDAP or TAnPDAP (35 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm). The TAnDAP OLED device showed C.I.E. value of (0.28, 0.41) and luminance efficiency of 3.81 cd/A at 10 mA/cm2. The TAnPDAP device showed C.I.E. value of (0.20, 0.27) and high luminance efficiency of 5.40 cd/A at 10 mA/cm2. TAnPDAP was found to show better luminance efficiency and C.I.E. value than TAnDAP because it has a bulky 9-phenylanthracene.

  14. Multi-color light-emitting transistors composed of organic single crystals

    NARCIS (Netherlands)

    Yomogida, Yohei; Sakai, Hayato; Sawabe, Kosuke; Gocho, Shota; Bisri, Satria Zulkarnaen; Nakanotani, Hajime; Adachi, Chihaya; Hasobe, Taku; Iwasa, Yoshihiro; Takenobu, Taishi

    2013-01-01

    We report a novel concept for multi-color light emission from an ambipolar organic single-crystal transistor using natural optical waveguides, the self-absorption effect, Davydov splitting and the unique alignment of the transition dipole moments. We used 9,10-bis(2,2-diphenylvinyl)-anthracene singl

  15. Detection of strand breaks in phiX 174 RFI and PM2 DNA reacted with ultimate and proximate carcinogens.

    Science.gov (United States)

    Thielmann, H W

    1977-10-01

    Supercoiled DNA duplexes of phages phiX 174 and PM2 were treated in aqueous solution at neutral pH with ultimate and proximate carcinogens. Subsequently, the carcinogen-treated phage DNAs were subjected to velocity sedimentation in neutral and alkaline sucrose to quantitative introduction of single strand breaks. Reaction of phage DNA with the ultimate carcinogens N-methyl-N-nitrosourea (MeNOUr), N-ethyl-N-nitrosourea (EtNOUr), 7-bromomethyl-benza[a]-anthracene, N-acetoxy-2-acetylaminofluorene [(Ac)2ONFln] and K-region oxides for short periods followed by sedimentation in neutral sucrose gradients led to very few breaks. Incubation with the proximate carcinogens N-hydroxy-2-acetylaminofluorene, 2-acetylaminofluorene, 7-methyl-, and 7,12-dimethyl-benza[a]anthracene did not result in breaks. However, when the phage DNAs were reacted with the ultimate carcinogens under the same conditions but subsequently alkali-denatured and sedimented in alkaline sucrose gradients, single strand breaks were readily introduced. Incubation with the proximate carcinogens followed by alkali denaturation and sedimentation in alkaline sucrose showed that only 7,12-dimethyl-benz[a]anthracene and, to a minor extent, 7-methyl-benz[]anthracene caused alkali-inducible breaks. The ability of N-methyl-N'-nitro-N-nitrosoguanidine to effect breakdown of superhelical phage DNA in alkali was found enhanced in the presence of N-acetyl-cysteine. PMID:145749

  16. Novel β-cyclodextrin modified quantum dots as fluorescent probes for polycyclic aromatic hydrocarbons (PAHs)

    Institute of Scientific and Technical Information of China (English)

    Cui Ping Han; Hai Bing Li

    2008-01-01

    Water-soluble CdSe/ZnS quantum dots (QDs)were prepared via a simple sonochemical procedure using β-cyclodextrin (CD)as surface coating agent.The QDs displayed a sensitive emission enhancement for anthracene over other related polycyclic aromatic hydrocarbons,and the detection limit was around 1.6 × 10-8 mol/L.

  17. Photooxygenation and gas-phase reactivity of multiply threaded pseudorotaxanes.

    Science.gov (United States)

    Nowosinski, Karol; Warnke, Stephan; Pagel, Kevin; Komáromy, Dávid; Jiang, Wei; Schalley, Christoph A

    2016-04-01

    The solution-phase photooxygenation of multiply threaded crown/ammonium pseudorotaxanes containing anthracene spacers is monitored by electrospray ionization Fourier-transform ion-cyclotron-resonance (ESI-FTICR) mass spectrometry. The oxygenated pseudorotaxanes are mass-selected and fragmented by infrared multiphoton dissociation (IRMPD) and/or collision-induced dissociation (CID) experiments and and their behavior compared to that of the non-oxygenated precursors. [4+2]Cycloreversion reactions lead to the loss of O2, when no other reaction channel with competitive energy demand is available. Thus, the release of molecular oxygen can serve as a reference reaction for the energy demand of other fragmentation reactions such as the dissociation of the crown/ammonium binding motifs. The photooxygenation induces curvature into the initially planar anthracene and thus significantly changes the geometry of the divalent, anthracene-spacered wheel. This is reflected in ion-mobility data. Coulomb repulsion in multiply charged pseudorotaxanes assists the oxygen loss as the re-planarization of the anthracene increases the distance between the two charges. PMID:27041657

  18. Photoinduced energy transfer across non-covalent bonds in the nanoscale: Cyclodextrin hosts with enhanced luminescent properties for guest communication

    NARCIS (Netherlands)

    J.A. Faiz; L.E.P. Kyllonen; P. Contreras-Carballada; R.M. Williams; L. De Cola; Z. Pikramenou

    2009-01-01

    Two photoactive cyclodextrin hosts have been prepared and studied in participation on photophysical processes, one with a ruthenium tris(bipyridyl) core which forms a trimeric host and the other with an appended anthracene unit. An acetylide functionalized bipyridyl cyclodextrin, 1, was prepared by

  19. The Effect of Interaction Between White-rot Fungi and Indigenous Microorganisms on Degradation of Polycyclic Aromatic Hydrocarbons in Soil

    Energy Technology Data Exchange (ETDEWEB)

    Wiesche, C. in der [Institute of Plant Nutrition and Soil Science, Federal Agricultural Research Centre (Germany)], E-mail: carsten.wiesche@fal.de; Martens, R. [Institute of Agroecology, Federal Agricultural Research Centre (Germany); Zadrazil, F. [Institute of Plant Nutrition and Soil Science, Federal Agricultural Research Centre (Germany)

    2003-05-15

    White-rot fungi applied for soil bioremediation have to compete with indigenous soil microorganisms. The effect of competition on both indigenous soil microflora and white-rot fungi was evaluated with regard to degradation of polycyclic aromatic hydrocarbons (PAH) with different persistence in soil. Sterile and non-sterile soil was artificially contaminated with {sup 14}C-labeled PAH consisting of three (anthracene), four (pyrene, benz[a]anthracene) and five fused aromatic rings (benzo[a]pyrene, dibenz[a,h]anthracene). The two fungi tested,Dichomitus squalens and Pleurotus ostreatus, produced similar amounts of ligninolytic enzymes in soil, but PAH mineralization by P. ostreatus was significantly higher. Compared to the indigenous soil microflora, P.ostreatus mineralized 5-ring PAH to a larger extent, while the indigenous microflora was superior in mineralizing 3-ring and 4-ring PAH. In coculture the special capabilities of both soil microflora and P. ostreatus were partly restricted due to antagonistic interactions, but essentially preserved. Thus, soil inoculation with P. ostreatus significantly increased the mineralization of high-molecular-weight PAH, and at the same time reduced the mineralization of anthracene and pyrene. Regarding the mineralization of low-molecular-weight PAH, the stimulation of indigenous soil microorganisms by straw amendment was more efficient than application of white-rot fungi.

  20. Accumulation and degradation of dead-end metabolites during treatment of soil contaminated with polycyclic aromatic hydrocarbons with five strains of white-rot fungi

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, B.E. [Centre for Chemistry and Chemical Engineering, Dept. of Biotechnology, Lund Univ. (Sweden); Henrysson, T. [Centre for Chemistry and Chemical Engineering, Dept. of Biotechnology, Lund Univ. (Sweden)

    1996-12-31

    The white-rot fungi Trametes versicolor PRL 572, Trametes versicolor MUCL 28407, Pleurotus ostreatus MUCL 29527, Pleurotus sajor-caju MUCL 29757 and Phanerochaete chrysosporium DSM 1556 were investigated for their ability to degrade the polycyclic aromatic hydrocarbons (PAH) anthracene, benz[a]anthracene and dibenz[a, h]anthracene in soil. The fungi were grown on wheat straw and mixed with artificially contaminated soil. The results of this study show that, in a heterogeneous soil environment, the fungi have different abilities to degrade PAH, with Trametes showing little or no accumulation of dead-end metabolites and Phanerochaete and Pleurotus showing almost complete conversion of anthracene to 9,10-anthracenedione. In contrast to earlier studies, Phanerochaete showed the ability to degrade the accumulated 9,10-anthracenedione while Pleurotus did not. This proves that, in a heterogeneous soil system, the PAH degradation pattern for white-rot fungi can be quite different from that in a controlled liquid system. (orig.)

  1. Interaction of aromatic compounds with Photobacterium leiognathi luciferase: fluorescence anisotropy study

    NARCIS (Netherlands)

    Kudryasheva, N.S.; Nemtseva, E.V.; Visser, A.J.W.G.; Hoek, van A.

    2003-01-01

    The time-resolved and steady-state fluorescence techniques were employed to elucidate possible interactions of four aromatic compounds (anthracene, POPOP, MSB and 1,4-naphthalendiol) with bacterial luciferase. Fluorescence spectra and fluorescence anisotropy decays of these compounds were studied in

  2. Role of arbuscular mycorrhizal fungus Rhizophagus custos in the dissipation of PAHs under root-organ culture conditions

    International Nuclear Information System (INIS)

    Polycyclic aromatic hydrocarbons (PAHs) are one of the most common contaminants in soil. Arbuscular mycorrhizal (AM) fungi make host plants resistant to pollutants. This study aims to evaluate the impact of anthracene, phenanthrene and dibenzothiophene on the AM fungus Rhizophagus custos, isolated from soil contaminated by heavy metals and PAHs, under monoxenic conditions. We found a high level of tolerance in R. custos to the presence of PAHs, especially in the case of anthracene, in which no negative effect on AM-colonized root dry weight (root yield) was observed, and also a decrease in the formation of anthraquinone was detected. Increased PAH dissipation in the mycorrhizal root culture medium was observed; however, dissipation was affected by the level of concentration and the specific PAH, which lead us to a better understanding of the possible contribution of AM fungi, and in particular R. custos, to pollutant removal. -- Highlights: •The AM fungus R. custos contributes to PAH dissipation and removal from the medium. •R. custos showed high levels of tolerance to high concentrations of anthracene. •Phenanthrene negatively affects the functionality of the symbiosis. •R. custos accumulates PAHs in spores and extraradical mycelia. •R. custos is able to prevent PAHs from entering roots. -- The AM fungus Rhizophagus custos is involved in PAH dissipation in absence of other microorganisms and could be potentially effective in protecting anthracene exposed plants

  3. Role of nutrients in the utilization of polycyclic aromatic hydrocarbons by halotolerant bacterial strain

    Institute of Scientific and Technical Information of China (English)

    Pugazhcndi Arulazhagan; Namsivayam Vasudevan

    2011-01-01

    A halotolerant bacterial strain VA1 isolated from marine environment was studied for its ability to utilize polycylic aromatic hydrocarbons (PAHs) under saline condition.Anthracene and pyrene were used as representatives for the utilization of PAH by the bacterial strain.Glucose and sodium citrate were used as additional carbon sources to enhance the PAH utilization.The strain VA1was able to utilize anthracene (73%) and pyrene (66%) without any additional substrate.In the presence of additional carbon sources (glucose/sodium citrate) the utilization of PAH was faster.PAH was utilized faster by VA1 in the presence of glucose than sodium citrate.The stain utilized 87% and 83% of anthracene and pyrene with glucose as carbon source and with sodium citrate the strain utilized 81%and 76% respectively in 4 days.Urea as an alternative source of nitrogen also enhanced the utilization of PAHs (anthracene and pyrene)by the bacterial strain up to 88% and 84% in 4 days.Sodium nitrate as nitrogen source was not able to enhance the PAH utilization rate.Phenotypic and phlyogenetic analysis proved that the PAHs utilizing halotolerant strain VA1 belongs to Ochrobactrum sp.

  4. Resonance raman and absorption spectra of isomeric retinals in their lowest excited triplet states

    DEFF Research Database (Denmark)

    Wilbrandt, Robert Walter; Jensen, N.-H.; Houee-Levin, C.

    1985-01-01

    implications about the size of the energy barriers separating the various triplet species are discussed. The resonance Raman spectra obtained by using either anthracene (ET = 177.7 kJ mol-1) or naphthalene (ET = 254.8 kJ mol-1) as sensitizers were virtually identical for the corresponding triplet states from...

  5. Predictions of Resuspension of Highway Detention Pond Deposits in Interrain Event Periods due to Wind-Induced Currents and Waves

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Larsen, Torben; Rasmussen, Michael R.

    2009-01-01

    (a,h)anthracene and indeno(1,2,3-cd)pyrene (PAHs) and the heavy metals of cadmium, chromium, copper, lead, nickel, and zinc. The current and wave-generated bed-shear stresses entail a discharged bulk of pollutants corresponding to approximately 10% of the annual accumulation of pollutants in the present pond due...

  6. Candidates for the development of consortia capable of petroleum hydrocarbon degradation in marine environment

    Digital Repository Service at National Institute of Oceanography (India)

    David, J.; Gupta, R.; Mohandass, C.; Nair, S.; LokaBharathi, P.A.; Chandramohan, D.

    strains were found to degrade crude oil. Some of the bacterial strains could degrade more than 90% of the aliphatic fractions and more than 50% of the aromatic component. These could also oxidize pure aromatics like naphthalene (80%) and anthracene (55...

  7. Detection of Neutrons with Scintillation Counters

    Science.gov (United States)

    Hofstadter, R.

    1948-11-01

    Detection of slow neutrons by: detection of single gamma rays following capture by cadmium or mercury; detection of more than one gamma ray by observing coincidences after capture; detection of heavy charged particles after capture in lithium or baron nuclei; possible use of anthracene for counting fast neutrons investigated briefly.

  8. Assessment of drug salt release from solutions, suspensions and in situ suspensions using a rotating dialysis cell

    DEFF Research Database (Denmark)

    Parshad, Henrik; Frydenvang, Karla; Liljefors, Tommy;

    2003-01-01

    A rotating dialysis cell consisting of a small (10 ml) and a large compartment (1000 ml) was used to study the release of drug salt (bupivacaine 9-anthracene carboxylate) from (i). solutions, (ii). suspensions and (iii). in situ formed suspensions. Initial release experiments from suspensions...

  9. Synthesis of Silica-anchored Sensitizer and its Application in the Preparation of Previtamin D3 from Tachysterol

    Institute of Scientific and Technical Information of China (English)

    Chang Jiang YOU; Rong XIE; Yun Yan GAO; Yong Bin HAN; Guo Qiang YANG; Yi LI

    2004-01-01

    A silica gel-anchored photosensitizer was synthesized with anthracene as sensitizer moiety. The photoisomerization of tachysterol to previtamin D3 was carried out with this heterogeneous photosensitizer in ethanol. The experiment results demonstrate that this solid phase photosensitizer is efficient for the photoisomerization and can be simply separated from the reaction mixture by filtration.

  10. Characterization of polycyclic aromatic hydrocarbons in fugitive PM10 emissions from an integrated iron and steel plant.

    Science.gov (United States)

    Khaparde, V V; Bhanarkar, A D; Majumdar, Deepanjan; Rao, C V Chalapati

    2016-08-15

    Fugitive emissions of PM10 (particles <10μm in diameter) and associated polycyclic aromatic hydrocarbons (PAHs) were monitored in the vicinity of coking unit, sintering unit, blast furnace and steel manufacturing unit in an integrated iron and steel plant situated in India. Concentrations of PM10, PM10-bound total PAHs, benzo (a) pyrene, carcinogenic PAHs and combustion PAHs were found to be highest around the sintering unit. Concentrations of 3-ring and 4-ring PAHs were recorded to be highest in the coking unit whereas 5-and 6-ring PAHs were found to be highest in other units. The following indicatory PAHs were identified: indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene, benzo (k) fluoranthene in blast furnace unit; indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene, chrysene in sintering unit; Anthracene, fluoranthene, chrysene in coking unit and acenaphthene, fluoranthene, fluorene in steel making unit. Total-BaP-TEQ (Total BaP toxic equivalent quotient) and BaP-MEQ (Total BaP mutagenic equivalent quotient) concentration levels ranged from 2.4 to 231.7ng/m(3) and 1.9 to 175.8ng/m(3), respectively. BaP and DbA (dibenzo (a,h) anthracene) contribution to total-BaP-TEQ was found to be the highest. PMID:27099996

  11. Eisenia fetida increased removal of polycyclic aromatic hydrocarbons from soil

    International Nuclear Information System (INIS)

    The removal of phenanthrene, anthracene and benzo(a)pyrene added at three different concentrations was investigated with or without earthworms (Eisenia fetida) within 11 weeks. Average anthracene removal by the autochthonous micro-organisms was 23%, 77% for phenanthrene and 13% for benzo(a)pyrene, while it was 51% for anthracene, 47% for benzo(a)pyrene and 100% for phenanthrene in soil with earthworms. At 50 and 100 mg phenanthrene kg-1 E. fetida survival was 91% and 83%, but at 150 mg kg-1 all died within 15 days. Survival of E. fetida in soil amended with anthracene ≤1000 mg kg-1 and benzo(a)pyrene ≤150 mg kg-1 was higher than 80% and without weight loss compared to the untreated soil. Only small amounts of PAHs were detected in the earthworms. It was concluded that E. fetida has the potential to remove large amounts of PAHs from soil, but more work is necessary to elucidate the mechanisms involved. - Addition of earthworms, Eisenia fetida, accelara removal of polycyclic aromatic hydrocarbons from soil

  12. Effects of Autoclaving and Mercuric Chloride Sterilization on PAHs Dissipation in a Two-Liquid-Phase Soil Slurry

    Institute of Scientific and Technical Information of China (English)

    WANG Cong-Ying; WANG Fang; WANG Tao; YANG Xing-Lun; BIAN Yong-Rong; F.O.KENGARA; LI Zeng-Bo; JIANG Xin

    2011-01-01

    A two-liquid-phase (TLP) soil slurry system was employed to quantify the efficiencies of autoclaving and mercuric chloride sterilization in the dissipation of polycyclic aromatic hydrocarbons (PAHs). The fates of 11 PAHs (naphthalene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, dibenzo(a, h)anthracene) were recorded over 113 days of incubation. No microorganisms were detected in the HgCl2-sterilized soil slurries during the whole incubation period, indicating very effective sterilization. However, about 2%-36% losses of PAHs were observed in the HgCl2-sterilized slurry. In contrast to the HgCl2-sterilized soil slurry, some microorganisms survived in the autoclaved soil slurries. Moreover,significant biodegradation of 6 PAHs (naphthalene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene) was observed in the autoclaved soil slurries. This indicated that biodegradation results of PAHs in the soil slurries, calculated on basis of the autoclaved control, would be underestimated. It could be concluded that the sterilization efficiency and effectiveness of HgCl2 on soil slurry was much higher than those of autoclaving at 121 ℃ for 45 min.

  13. HYDROGENATION OF POLYCYCLIC AROMATIC COMPOUNDS USING NI SUPPORT ON H-BETA ZEOLITE IN SUPERCRITICAL CARBON DIOXIDE

    Science.gov (United States)

    The primary rationale for use of supercritical carbon dioxide as a solvent in hydrogenation is the elimination of mass transfer limitations, through enhancement of the solubility of hydrogen at the reaction locus. Hydrogenation of anthracene was performed using NiHB-zeolite catal...

  14. Highly efficient non-doped blue organic light emitting devices based on anthracene–pyridine derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Haykir, Gulcin; Tekin, Emine; Atalar, Taner; Türksoy, Figen

    2013-12-02

    Four different 2-(10-aryl)anthracen-9-yl)pyridine derivatives 5a–d were synthesized via the Suzuki cross-coupling reaction. Photo-physical characteristics of these materials having strong electron donating or electron withdrawing groups were explored. Multilayer small molecule organic light emitting diodes without any dopant were fabricated in the following sequence: Indium tin oxide/4,4′-bis(N-(1-naphthyl)-N-phenylamino)biphenyl (50 nm)/5a–d (30 nm)/4,7-diphenyl-1,10-phenanthroline (30 nm)/LiF/Al. The electroluminescent property of the device fabricated with 5d as an emitter exhibited a high external quantum efficiency of 3.80% (at around 1 mA/cm{sup 2}) with Commission Internationale De L'Eclairage coordinates of (0.14, 0.25). - Highlights: • Synthesis and characterization of 2-(10-aryl)anthracen-9-yl)pyridine derivatives • Thermal, photophysical and electrochemical properties of anthracene derivatives • Emitters from blue to greenish blue for organic light emitting device applications • Organic light emitting device fabrication and characterization of 2-(10-aryl)anthracen-9-yl)pyridine derivatives.

  15. Synthesis, DNA-damaging and cytotoxic properties of novel topoisomerase II-directed bisantrene analogues.

    Science.gov (United States)

    Zagotto, G; Oliva, A; Guano, F; Menta, E; Capranico, G; Palumbo, M

    1998-01-20

    New bisantrene analogues were synthesized, bearing one or two 4,5-dihydro-1H-imidazol-2-yl hydrazone side chains at positions 1,4 or 9 of the anthracene ring system. A 10-azabioisostere was also prepared. The position of substituents in structurally isomeric drugs modulates topoisomerase II poisoning and specificity, along with cytotoxicity. PMID:9871638

  16. DFT Study on Electronic Structures and Spectroscopic Properties of Oligo(silanylenediethynylanthracene)%寡聚(亚硅基二炔基蒽)电子结构和光谱性质的密度泛函理论研究

    Institute of Scientific and Technical Information of China (English)

    张培斌; 黄昕暐; 李歆; 滕启文

    2011-01-01

    Poly(silanylenediethynylanthracene) (PSDEA) exhibits a hole-transporting ability experimentally. In order to simulate the property of PSDEA, a series of silanylenediethynylanthracene oligomers were designed. The structures of these oligomers were optimized byusing density function theory at B3LYP/6-31G(d) level. The energy gaps of the oligomers decrease with the increase in the chain length. The energy gaps of the oligomers also decrease in the presence of the electron-withdrawing group on the anthracene ring. The 13C chemical shifts and nucleus independent chemical shifts (NICS) at the anthracene ring center in the oligomers were calculated at B3LYP/6-31G level. The chemical shifts of the carbon atoms connected with the nitryl group changed upfield, compared with those of the carbon atoms without the nitryl group. The aromaticity at the anthracene ring center decreases in the presence of the electron-withdrawing group, whereas increases with the increase in the number of the silanylene units. The most sensitive location for calculating the NICS values is 0.1 nm above the anthracene plane.

  17. Synthesis and Property of New Propeller Shaped Emitting Materials for Organic Light-Emitting Devices.

    Science.gov (United States)

    Kang, Seokwoo; Lee, Hayoon; Kim, Beomjin; Park, Youngil; Park, Jongwook

    2016-03-01

    New propeller type emitting compound, namely 3,6-di-anthracen-9-yl-9,10-bis-(4-anthracen-9-yi-phenyl)-phenanthrene[TAnDAP] and 3,6-bis-(10-phenyl-anthracen-9-yl)-9,10-bis-[4-(10-phenyl-anthracen-9-yl)-phenyl]-phenanthrene [TAnPDAP] were synthesized through Suzuki and McMurry reactions. We investigated their physical properties such as optical, electrochemical, and electroluminescent properties. The two compounds were used as an emitting layer in OLED devices: ITO/2-TNATA (60 nm)/NPB (15 nm)/non-doped: TAnDAP or TAnPDAP (35 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm). The TAnDAP OLED device showed C.I.E. value of (0.28, 0.41) and luminance efficiency of 3.81 cd/A at 10 mA/cm2. The TAnPDAP device showed C.I.E. value of (0.20, 0.27) and high luminance efficiency of 5.40 cd/A at 10 mA/cm2. TAnPDAP was found to show better luminance efficiency and C.I.E. value than TAnDAP because it has a bulky 9-phenylanthracene. PMID:27455768

  18. Photoinduced toxicity single and binary mixtures of four polycyclic aromatic hydrocarbons to the marine diatom Skeletonema costatum

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Diatom Skeletonema costatum Cleve is one of the main predominant phytoplankton species in the Changjiang Estuary in China. In order to provide some basic information for future assessment of the potential risk on phytoplankton communities in this estuary caused by polycyclic aromatic hydrocarbons(PAHs), this alga was selected as a representative to investigate the photoinduced toxicity of PAHs, in single and mixture. Four PAHs including three-ring phenanthrene and anthracene, four-ring fluoranthene and pyrene were tested in the laboratory. The single toxicity of each PAH on this microalga was compared with and without the simulated solar UV radiation. The results showed that this microalga was sensitive to PAH's photoinduced toxicity. Ratios of the 72 h median effect concentration obtained for fluorescent and UV light tests were about 8.4 for phenanthrene, 13.0 for anthracene, 6.5 for fluoranthene, and 5.7 for pyrene, indicating that UV light enhanced the PAH toxicity to this alga significantly. Under the fluorescent radiation (lacking UV), the dose-response curves based on chemical concentrations revealed that the order of toxic strength was fluoranthene greater than pyrene greater than anthracene greater than phenanthrene; while under the UV radiation (476 μW/cm2 for UVA, 6.5 μW/cm2 for UVB) it became fluoranthene approximately equaling anthracene greater than pyrene greater than phenanthrene, indicating that the UV light also changed its relative toxicity to this alga. The photoinduced toxicity of PAHs to the marine diatom S. costatum might be a synergistic effect of photosensitization reactions (e.g., generation of single-state oxygen) and photomodification (photooxidation and/or photolysis).The combined effects of six binary mixtures on the marine diatom S. costatum were investigated using the additive-index method. Four binary-mixtures (phenanthrene plus anthracene; phenanthrene plus pyrene; anthracene plus fluoranthene; anthracene plus pyrene) were found

  19. Hard Cap Espresso Machines in Analytical Chemistry: What Else?

    Science.gov (United States)

    Armenta, Sergio; de la Guardia, Miguel; Esteve-Turrillas, Francesc A

    2016-06-21

    A hard cap espresso machine has been used in combination with liquid chromatography with molecular fluorescence detection for the determination of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils and sediments providing appropriate extraction efficiencies and quantitative results. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benz[b]fluoranthene, benz[k]fluoranthene, benz[a]pyrene, dibenz[a,h]anthracene, benz[ghi]perylene, and indeno[1,2,3-cd]pyrene were used as target compounds. It should be mentioned that the pairs benz[a]anthracene-chrysene and dibenz[a,h]anthracene-benz[ghi]perylene peaks coelute under the employed chromatographic conditions; thus, those compounds were determined together. PAHs were extracted from 5.0 g of soil, previously homogenized, freeze-dried, and sieved to 250 μm, with 50 mL of 40% (v/v) acetonitrile in water at a temperature of 72 ± 3 °C. The proposed procedure is really fast, with an extraction time of 11 s, and it reduces the required amount of organic solvent to do the sample preparation. The obtained limit of detection for the evaluated PAHs was from 1 to 38 μg kg(-1). Recoveries were calculated using clean soils spiked with 100, 500, 1000, and 2000 μg kg(-1) PAHs with values ranging from 81 to 121% and good precision with relative standard deviation values lower than 30%. The method was validated using soil and sediment certified reference materials and also using real samples by comparison with ultrasound-assisted extraction, as reference methodology, obtaining statistically comparable results. Thus, the use of hard cap espresso machines in the analytical laboratories offers tremendous possibilities as low cost extraction units for the extraction of solid samples. PMID:27224000

  20. Remediation of PAHs in a saline-alkaline soil amended with wastewater sludge and the effect on dynamics of C and N.

    Science.gov (United States)

    Fernández-Luqueño, F; Marsch, R; Espinosa-Victoria, D; Thalasso, F; Hidalgo Lara, M E; Munive, A; Luna-Guido, M L; Dendooven, L

    2008-08-25

    Contamination of soil with hydrocarbons occurs frequently and organic material, such as sludge, is often applied to accelerate their dissipation. Little is known, however, how sludge characteristics affect removal of polycyclic aromatic hydrocarbons (PAHs) from alkaline-saline soil. Soil of the former lake Texcoco with pH 9 and electrolytic conductivity 7 dS m(-1) was contaminated with phenanthrene and anthracene and amended with sludge, sterilized sludge, sludge adjusted to maintain pH in contaminated soil or glucose plus an inorganic N and P source while emission of CO2 and concentrations of NH4+, NO3-, NO2-, extractable P, phenanthrene and anthracene were monitored in an aerobic incubation experiment of 112 days. An agricultural soil from Acolman treated in the same way served as control. Contaminating the Texcoco soil increased emission of CO2 significantly, but not in the Acolman soil. After 112 days, the largest concentration of anthracene and phenanthrene was found in the Acolman soil added with glucose and the lowest in the sludge-amended soil. The largest concentration of anthracene in the Texcoco soil was found in soil added with sterile sludge and the lowest in the sludge-amended soil. The largest concentration of phenanthrene in the Texcoco soil was found in the glucose-amended soil and the lowest in the sludge-amended soil. It was found that addition of sludge removed more phenanthrene, but not anthracene from soil compared to the unamended contaminated soil, glucose inhibited dissipation of PAHs while microorganisms in the sludge contributed to their removal, and adjustment of soil pH had no effect. Organic material can be used to accelerate removal of hydrocarbons from soil, but the effect is controlled by soil type, contaminant and organic material characteristics.

  1. Hard Cap Espresso Machines in Analytical Chemistry: What Else?

    Science.gov (United States)

    Armenta, Sergio; de la Guardia, Miguel; Esteve-Turrillas, Francesc A

    2016-06-21

    A hard cap espresso machine has been used in combination with liquid chromatography with molecular fluorescence detection for the determination of polycyclic aromatic hydrocarbons (PAHs) from contaminated soils and sediments providing appropriate extraction efficiencies and quantitative results. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benz[b]fluoranthene, benz[k]fluoranthene, benz[a]pyrene, dibenz[a,h]anthracene, benz[ghi]perylene, and indeno[1,2,3-cd]pyrene were used as target compounds. It should be mentioned that the pairs benz[a]anthracene-chrysene and dibenz[a,h]anthracene-benz[ghi]perylene peaks coelute under the employed chromatographic conditions; thus, those compounds were determined together. PAHs were extracted from 5.0 g of soil, previously homogenized, freeze-dried, and sieved to 250 μm, with 50 mL of 40% (v/v) acetonitrile in water at a temperature of 72 ± 3 °C. The proposed procedure is really fast, with an extraction time of 11 s, and it reduces the required amount of organic solvent to do the sample preparation. The obtained limit of detection for the evaluated PAHs was from 1 to 38 μg kg(-1). Recoveries were calculated using clean soils spiked with 100, 500, 1000, and 2000 μg kg(-1) PAHs with values ranging from 81 to 121% and good precision with relative standard deviation values lower than 30%. The method was validated using soil and sediment certified reference materials and also using real samples by comparison with ultrasound-assisted extraction, as reference methodology, obtaining statistically comparable results. Thus, the use of hard cap espresso machines in the analytical laboratories offers tremendous possibilities as low cost extraction units for the extraction of solid samples.

  2. Heavy metal ions affecting the removal of polycyclic aromatic hydrocarbons by fungi with heavy-metal resistance.

    Science.gov (United States)

    Ma, Xiao-Kui; Ling Wu, Ling; Fam, Hala

    2014-12-01

    The co-occurrence of polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) is very common in contaminated environments. It is of paramount importance and great challenge to exploit a bioremediation to remove PAHs in these environments with combined pollution. We approached this question by probing the influence of HMs coexisting with PAHs on the removal of PAHs by Acremonium sp. P0997 possessing metal resistance. A removal capability for naphthalene, fluorene, phenanthrene, anthracene, and fluoranthenepresentalone (98.6, 99.3, 89.9, 60.4, and 70 %, respectively) and in a mixture (96.9, 71.8, 67.0, 85.0, and 87.9 %, respectively) was achieved in mineral culture inoculated with Acremonium sp. P0997, and this strain also displayed high resistance to the individual HMs (Mn(2+), Fe(2+), Zn(2+), Cu(2+), Al(3+), and Pb(2+)). The removal of individual PAHs existing in a mixture was differently affected by the separately tested HMs. Cu(2+)enhanced the partition process of anthracene to dead or alive mycelia and the contribution of the biosorption by this strain but imposed a little negative influence on the contribution of biodegradation to the total removal of anthracene individually in a culture. However, Mn(2+) had an inhibitory effect on the partition process of anthracene to dead or alive mycelia and decreased the contributions of both biosorption and biodegradation to the total anthracene removal. This work showcased the value of fungi in bioremediation for the environments with combined pollution, and the findings have major implications for the bioremediation of organic pollutants in metal-organic mixed contaminated sites.

  3. Partition of polycyclic aromatic hydrocarbons on organobentonites

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A series of organobentonites synthesized by exchanging organiccation such as dodecyltri-methylammonium (DTMA),benzyldimethyltetradecylammonium (BDTDA), cetyltrimethyl-ammonium (CTMA), octodeyltrimethylammonium (OTMA) on bentonite. The optimal condition, properties and mechanisms for the organobentonites to sorb phenanthrene, anthracene, naphthalene, acenaphthene in water were investigated in detail. The partition behavior was determined for four polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, phenanthrene, anthracene and acenaphthene, from water to a series of organobentonites. The interlayer spacings and organic carbon contents of organobentonites, removal rate and sorption capacities for organobentonites to treat phenanthrene,anthracene, naphthalene, acenaphthene were correlated to the length of alkyl chains and the amounts of cation surfactant exchanged on Foundation item: the bentonite. Phenanthrene, anthracene, naphthalene, and acenaphthene sorption to organobentonites were characterized by linear isotherms, indicating solute partition between water and the organic phase composed of the large alkyl functional groups of quaternary ammonium cations. PAHs distribution coefficients (Kd)between organobentonites and water were proportional to the organic carbon contents of organobentonites. However, the partition coefficients (Koc) were nearly constants for PAHs in the system of organobentonite-water. The Koc of phenanthrene, anthracene,naphthalene, acenaphthene were 2.621x105, 2.106x105, 2.247x104,5.085x104, respectively. The means Koc values on the organobentonites are about ten to twenty times larger than the values on the soils/sediments, what is significant prerequisite for organobentonite to apply to remediation of pollution soil and groundwater. The sorption mechanism was also evaluated from octanol-water partition coefficients and aqueous solubility of PAHs. The correlations between lgKoc and 1gkow, 1gKoc and 1gS for PAHs in the system of water

  4. Experimental verifications on chemical carcinogenesis, a bifunctional alkylation between DNA interstrands

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    It is evidenced by the filter elution method that two carcinogenic aromatic hydrocarbons, benzo[a]pyrene and dibenzo[a,h]anthracene, two carcinogenic metal salts, beryllium chloride and cadmium chloride, four carcinogenic aromatic amines, 2-aminofluorene, β-naphthylamine, 4-aminobiphenyl and benzidine, can all induce DNA interstrand and DNA-protein cross-link in L1210 culture. However, under the same condition, the corresponding non-carcinogenic compounds, including benzo[k]fluorancene, anthracene, magnesium chloride, zinc chloride, a -naphthylamine, 2-aminobiphenyl and m-toluidine, cannot produce any cross-link adducts. All these results are consistent with the di-region theory that carcinogens are bio-bifunctional alkylation agents. This method can also be used to discriminate carcinogens and non-carcinogens.

  5. PAHs in corn grains submitted to drying with firewood.

    Science.gov (United States)

    de Lima, Rafael Friedrich; Dionello, Rafael Gomes; Peralba, Maria do Carmo Ruaro; Barrionuevo, Simone; Radunz, Lauri Lourenço; Reichert Júnior, Francisco Wilson

    2017-01-15

    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. he results showed the presence of seven compounds: fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene and chrysene. PMID:27542463

  6. (Z-3-(9-Anthryl-1-(4-chlorophenyl-2-(4-nitro-1H-imidazol-1-ylprop-2-en-1-one

    Directory of Open Access Journals (Sweden)

    Yi-yi Zhang

    2009-05-01

    Full Text Available In the title compound, C26H16ClN3O3, the dihedral angle between the anthracene mean plane and imidazole ring is 64.75 (2°. In the crystal, π–π interactions between anthracene fragments lead to the formation of stacks of molecules propagating in [100]. The short distance between the carbonyl groups of symmetry-related molecules [C...O = 2.985 (2 Å] indicates the existence of dipole–dipole interactions. The crystal packing also exhibits short intermolecular contacts between the nitro groups and Cl atoms [Cl...O = 3.181 (2 Å].

  7. Synthetic Fuels Program

    International Nuclear Information System (INIS)

    Progress is reported on aquatic transport studies with regard to photolysis of polycyclic compounds in water; volatilization of PAH from water; bioaccumulation of anthracene by fathead minnows; bioaccumulation of polycyclic aromatic hydrocarbons by aquatic invertebrates; bioaccumulation of arylamines by zooplankton; availability of sediment-bound trace metals to bluegill; microbial transformation; transport and transformation of anthracene in natural waters; and microcosm studies. Progress is also reported on acute and chronic aquatic effects; acute and chronic terrestrial effects; leaching and chemical and physical characterization of solid wastes; toxicology of solid wastes; and field site task studies with regard to aquatic transport behavior of trace contaminants in wastewater discharges and airborne contaminants at coking plant field site

  8. Induction of active melanocytes in mouse skin by carcinogens: a new method for detection of skin carcinogens.

    Science.gov (United States)

    Iwata, K; Inui, N; Takeuchi, T

    1981-01-01

    Application of potent skin carcinogens, such as 7,12-dimethylbenz[a]anthracene, 3-methylcholanthrene, benzo[a]pyrene and 4-nitroquinoline-1-oxide, induced numerous dihydroxyphenylalanine (dopa)-positive cells in the interfollicular epidermis of C57BL/6 mice in a dose- and time-dependent fashion. Chrysene, a weak skin carcinogen, and croton oil, a tumor promoter, also induced 3--4 times more dopa-positive cells than acetone. Liver carcinogens, such as 3'-methyl-4-dimethylaminoazobenzene and N-2-acetylaminofluorene, and non-carcinogenic aromatic hydrocarbons, such as anthracene, fluoranthene, fluorene and pyrene, did not induce increase in these cells. These results indicate that increase in the number of dopa-positive cells after application of chemicals is well correlated with the abilities of these compounds to induce skin carcinogenesis and suppress sebaceous glands. PMID:7273337

  9. Repair of DNA treated with γ-irradiation and chemical carcinogens. Comprehensive report of entire period of ERDA support from June 1, 1975--January 15, 1978

    International Nuclear Information System (INIS)

    A partially purified enzyme fraction isolated from E. coli showed an N-glycosidase activity as well as a phosphodiesterase activity on DNA treated with methylnitrosourea, and with 7-bromomethylbenz(a)anthracene and a phosphodiesterase activity against γ-irradiated DNA. Both 0-6 methyl guanine and 3-methyladenine were released from DNA treated with MNU; the adenine and guanine derivatives from the DNA treated with 7-bromomethyl-12-methylbenz(a)anthracene were also liberated. Progress is also reported on studies on Endonucleases II and VI and Exonuclease III of E. coli; methods for assay and for synthesis of substrates; attempts at purification of repair enzymes from mammalian tissues; and β-propiolactone reactions with deoxynucleosides and with DNA

  10. Tunneling of electrons via rotor-stator molecular interfaces: combined ab initio and model study

    CERN Document Server

    Petreska, Irina; Pejov, Ljupco; Kocarev, Ljupco

    2015-01-01

    Tunneling of electrons through rotor-stator anthracene aldehyde molecular interfaces is studied with a combined ab initio and model approach. Molecular electronic structure calculated from first principles is utilized to model different shapes of tunneling barriers. Together with a rectangular barrier, we also consider a sinusoidal shape that captures the effects of the molecular internal structure more realistically. Quasiclassical approach with the Simmons' formula for current density is implemented. Special attention is paid on conformational dependence of the tunneling current. Our results confirm that the presence of the side aldehyde group enhances the interesting electronic properties of the pure anthracene molecule, making it a bistable system with geometry dependent transport properties. We also investigate the transition voltage and we show that confirmation dependent field emission could be observed in these molecular interfaces at realistically low voltages. The present study accompanies our previ...

  11. 2-(9-Anthrylmethylideneamino-4-methylphenol

    Directory of Open Access Journals (Sweden)

    Andrés Villalpando

    2010-06-01

    Full Text Available The title compound, C22H17NO, is a novel Schiff base synthesized via a condensation reaction between 9-anthracenecarboxaldehyde and 2-amino-p-cresol. The asymmetric unit contains two independent molecules that are joined by an O—H...OH hydrogen bond. An intramolecular O—H...N hydrogen bond occurs in each molecule. π-stacking about inversion centers was observed between adjacent phenol rings [centroid–centroid distance = 3.850 (2 Å] and adjacent anthracene rings [centroid–centroid distance = 3.834 (2 Å]. The C—N=C—C torsion angles between the phenol and anthracene rings are close to 180° with values of 174.06 (15 and 179.85 (14°.

  12. Supramolecular nanoreactors for intracellular singlet-oxygen sensitization

    Science.gov (United States)

    Swaminathan, Subramani; Fowley, Colin; Thapaliya, Ek Raj; McCaughan, Bridgeen; Tang, Sicheng; Fraix, Aurore; Burjor, Captain; Sortino, Salvatore; Callan, John F.; Raymo, Françisco M.

    2015-08-01

    An amphiphilic polymer with multiple decyl and oligo(ethylene glycol) chains attached to a common poly(methacrylate) backbone assembles into nanoscaled particles in aqueous environments. Hydrophobic anthracene and borondipyrromethene (BODIPY) chromophores can be co-encapsulated within the self-assembling nanoparticles and transported across hydrophilic media. The reversible character of the noncovalent bonds, holding the supramolecular containers together, permits the exchange of their components with fast kinetics in aqueous solution. Incubation of cervical cancer (HeLA) cells with a mixture of two sets of nanoparticles, pre-loaded independently with anthracene or BODIPY chromophores, results in guest scrambling first and then transport of co-entrapped species to the intracellular space. Alternatively, incubation of cells with the two sets of nanocarriers in consecutive steps permits the sequential transport of the anthracene and BODIPY chromophores across the plasma membrane and only then allows their co-encapsulation within the same supramolecular containers. Both mechanisms position the two sets of chromophores with complementary spectral overlap in close proximity to enable the efficient transfer of energy intracellularly from the anthracene donors to the BODIPY acceptors. In the presence of iodine substituents on the BODIPY platform, intersystem crossing follows energy transfer. The resulting triplet state can transfer energy further to molecular oxygen with the concomitant production of singlet oxygen to induce cell mortality. Furthermore, the donor can be excited with two near-infrared photons simultaneously to permit the photoinduced generation of singlet oxygen intracellularly under illumination conditions compatible with applications in vivo. Thus, these supramolecular strategies to control the excitation dynamics of multichromophoric assemblies in the intracellular environment can evolve into valuable protocols for photodynamic therapy.An amphiphilic

  13. Application of the short and long consecutive pairs model to the triplet-doublet interaction in molecular crystals

    Science.gov (United States)

    Barhoumi, T.; Monge, J. L.; Bouchriha, H.

    2010-10-01

    We have adapted the model of two consecutive pairs to the study of the triplet-doublet (T-D) interaction in molecular crystals. We have applied this model to the modulation of the photoconductivity in crystalline anthracene by a static magnetic field (MFE) and a microwave field (PDMR). We were able to reproduce, for the first time, quite perfectly two types of experiments with the same set of kinetic constants.

  14. Peptide and protein sequence analysis by electron transfer dissociation mass spectrometry

    OpenAIRE

    Syka, John E. P.; Coon, Joshua J.; Schroeder, Melanie J.; Shabanowitz, Jeffrey; Hunt, Donald F.

    2004-01-01

    Peptide sequence analysis using a combination of gas-phase ion/ion chemistry and tandem mass spectrometry (MS/MS) is demonstrated. Singly charged anthracene anions transfer an electron to multiply protonated peptides in a radio frequency quadrupole linear ion trap (QLT) and induce fragmentation of the peptide backbone along pathways that are analogous to those observed in electron capture dissociation. Modifications to the QLT that enable this ion/ion chemistry are presented, and automated ac...

  15. Modeling of experimental data on trace elements and organic compounds content in industrial waste dumps.

    Science.gov (United States)

    Smoliński, Adam; Drobek, Leszek; Dombek, Václav; Bąk, Andrzej

    2016-11-01

    The main objective of the study presented was to investigate the differences between 20 mine waste dumps located in the Silesian Region of Poland and Czech Republic, in terms of trace elements and polycyclic aromatic hydrocarbons contents. The Principal Component Analysis and Hierarchical Clustering Analysis were applied in exploration of the studied data. Since the data set was affected by outlying objects, the employment of a relevant analysis strategy was necessary. The final PCA model was constructed with the use of the Expectation-Maximization iterative approach preceded by a correct identification of outliers. The analysis of the experimental data indicated that three mine waste dumps located in Poland were characterized by the highest concentrations of dibenzo(g,h,i)anthracene and benzo(g,h,i)perylene, and six objects located in Czech Republic and three objects in Poland were distinguished by high concentrations of chrysene and indeno (1.2.3-cd) pyrene. Three of studied mine waste dumps, one located in Czech Republic and two in Poland, were characterized by low concentrations of Cr, Ni, V, naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthen, benzo(a)anthracene, chrysene, benzo (b) fluoranthene, benzo (k) fluoranthene, benzo(a)pyrene, dibenzo(g,h,i)anthracene, benzo(g,h,i)perylene and indeno (1.2.3-cd) pyrene in comparison with the remaining ones. The analysis contributes to the assessment and prognosis of ecological and health risks related to the emission of trace elements and organic compounds (PAHs) from the waste dumps examined. No previous research of similar scope and aims has been reported for the area concerned. PMID:27497349

  16. Photosensitization of trans-Vitamin D3 to cis-Vitamin D3 in Heterogeneous System

    Institute of Scientific and Technical Information of China (English)

    Yong Bin HAN; Jin Ping CHEN; Yun Yan GAO; Bai Ning LIU; Guo Qiang YANG; Yi LI

    2005-01-01

    Two modes of heterogeneous photoisomerization of trans-vitamin D3 to cis-vitamin D3are described. The occurrence of isomerization on the substrate bounded to the polymeric support gives us the possibility in succession synthesis of 1α-hydroxyvitamin D3. The polymer-bound anthracene can sensitize isomerization of trans-vitamin D3 to cis-vitamin D3 efficiently and ease the separation process.

  17. Undistorted Cyclic Voltammograms at Scan Rates up to 2.5 MV·s-1 through Positive Feedback Compensation of Ohmic Drop

    Institute of Scientific and Technical Information of China (English)

    GUO Zhi-Yong郭智勇; LIN Xiang-Qin林祥钦; DENG Zhao-Xiang邓兆祥

    2004-01-01

    A circuit based on the current feedback operational amplifier was constructed to accomplish on-line ohmic drop compensation in ultrafast cyclic voltammetry. Firstly, its characteristics were confirmed experimentally on dummy cells. Then the reduction of anthracene in acetonitrile, a classical test example with very fast electron-tratnsfer kinetics, was examined to prove them too. The results showed that this circuit could afford excellent ohmic drop if 5% error is tolerated.

  18. Modification of acidity of Mo-Fe/HZSM-5 zeolite via argon plasma treatment

    Institute of Scientific and Technical Information of China (English)

    Xinli ZHU; Kailu YU; Dangguo CHENG; Yueping ZHANG; Qing XIA; Changjun LIU

    2008-01-01

    The NH3-TPD characterization was conducted to confirm that the acidity of Mo-Fe/HZSM-5 zeolite could be selectively modified via the glow discharge plasma treatment. The plasma catalyst treatment could totally change the distribution of aromatic products with higher methane conversion compared to the untreated catalyst. Some polycyclic aromatics such as anthracene, pyrene and phenanthrene were also produced over the plasma treated catalyst, in addition to benzene, toluene and naphthalene, which were normally obtained over the untreated catalyst.

  19. Extraction Optimization of Tinospora cordifolia and Assessment of the Anticancer Activity of Its Alkaloid Palmatine

    OpenAIRE

    Huma Ali; Savita Dixit

    2013-01-01

    Objective. To optimize the conditions for the extraction of alkaloid palmatine from Tinospora cordifolia by using response surface methodology (RSM) and study its anticancerous property against 7,12-dimethylbenz(a)anthracene (DMBA) induced skin carcinogenesis in Swiss albino mice. Methods. The effect of three independent variables, namely, extraction temperature, time, and cycles was investigated by using central composite design. A single topical application of DMBA (100  μ g/100  μ L of ace...

  20. Racemochrysone, a dihydroanthracenone from Senna racemosa.

    Science.gov (United States)

    Mena-Rejón, Gonzalo J; Pérez-Rivas, Karla; Sansorez-Peraza, Pablo; Rios, Tirso; Quijano, Leovigildo

    2002-01-01

    From the hexane extract of the bark of the stems of Senna racemosa (syn. Cassia racemosa) a new dihydroanthracenone derivative, named racemochrysone, was isolated. Its structure was established as 8,9-dihydroxy-3-methoxy-2,2,6-trimethyl-(2H)-anthracen-1-one based on spectroscopical data, mainly 1D and 2D NMR experiments. In addition beta-sitosterol, stigmasterol, chrysophanol and physcion were obtained. From the leaves extracts the piperidine alkaloid cassine and the hexitol pinitol were obtained.

  1. Synthesis of Heteroaromatic Compounds by Oxidative Aromatization Using an Activated Carbon/Molecular Oxygen System

    Directory of Open Access Journals (Sweden)

    Masahiko Hayashi

    2009-08-01

    Full Text Available A variety of heteroaromatic compounds, such as substituted pyridines, pyrazoles, indoles, 2-substituted imidazoles, 2-substituted imidazoles, 2-arylbenzazoles and pyrimidin-2(1H-ones are synthesized by oxidative aromatization using the activated carbon and molecular oxygen system. Mechanistic study focused on the role of activated carbon in the synthesis of 2-arylbenzazoles is also discussed. In the final section, we will disclose the efficient synthesis of substituted 9,10-anthracenes via oxidative aromatization.

  2. Polyamine Transport as a Target for Treatment of Pneumocystis Pneumonia▿

    OpenAIRE

    Liao, Chung-Ping; Phanstiel, Otto; Lasbury, Mark E.; Zhang, Chen; Shao, Shoujin; Durant, Pamela J.; Cheng, Bi-Hua; Lee, Chao-Hung

    2009-01-01

    Polyamine levels are greatly increased in alveolar macrophages (AMs) during Pneumocystis pneumonia (PCP), leading to increased production of H2O2, which causes AMs to undergo apoptosis. One of the mechanisms by which polyamine levels in AMs are elevated is enhanced uptake of exogenous polyamines. In this study, the possibility of targeting polyamine uptake as a treatment for PCP was examined. Four anthracene- and one benzene-polyamine conjugates that are potential polyamine transport inhibito...

  3. Mixture of Uncaria and Tabebuia Extracts are Potentially Chemopreventive in CBA/Ca Mice - A Long-term Experiment

    OpenAIRE

    Budán, Ferenc; Szabo, István; Varjas, Timea; Nowrasteh, Ghodratollah; Dávid, Tamás; Gergely, Péter; Varga, Zsuzsa; Molnár, Kornélia; Kádár, Balázs; Orsos, Zsuzsa; Kiss, István; Ember, István

    2010-01-01

    Abstract A long-term experimental animal model was developed by our research group for the evaluation of potential chemopreventive effects. The inhibitory effects of agents on carcinogen (7,12-Dimetilbenz[a]anthracene (DMBA)) induced molecular epidemiological biomarkers, in this case the expression of key onco/suppressor genes were investigated. Expression pattern of c-myc, Ha-ras, Bcl-2, K-ras protoonco and p53 tumoursuppressor genes were studied to elucidate early carcinogenic...

  4. 46 CFR Table 151.05 to Subpart 151... - Summary of Minimum Requirements

    Science.gov (United States)

    2010-10-01

    ... Coal tar pitch (molten) Atmos. Elev. III 1 i i 2 i i Integral Gravity PV Restr. II G-1 NR Vent F Yes... Anthracene oil (Coal tar fraction) Atmos. Amb.Elev. II 1 i i 2 i i Integral Gravity Open Open II G-1 NR Vent... install. Tank internal inspect. period—years a. b. c. d. e. f. g. h. i. j. k. l. m. n. o. p. q. Coal...

  5. Novel multiarm star block copolymer ionomers as proton conductive membranes

    OpenAIRE

    Demirel, Adem Levent; Erdoğan, Tuba; Bilir, Çiğdem; Ünveren, Elif; Tunca, Ümit

    2014-01-01

    A series of well-defined novel multiarm star block copolymer ionomers with an average of 6, 11 and 15 arms, sulfonated polystyrene-block-poly(2,2,3,3,3-pentafluoropropyl methacrylate) (SPS-b-PFPMA), were prepared via a combination of atom transfer radical polymerization (ATRP), Diels–Alder click reaction and postsulfonation reaction. First, multiarm star polymer with anthracene functionality as reactive periphery groups was prepared by a cross-linking reaction of divinyl benzene using ?-anthr...

  6. Explant culture of rat colon: A model system for studying metabolism of chemical carcinogens

    DEFF Research Database (Denmark)

    Autrup, Herman; Stoner, G.D.; Jackson, F.;

    1978-01-01

    An explant culture system has been developed for the long-term maintenance of colonic tissue from the rat. Explants of 1 cm2 in size were placed in tissue-culture dishes to which was added 2 ml of CMRL-1066 medium supplemented with glucose, hydrocortisone, beta-retinyl acetate, and either 2.5% bo......,12-dimethylbenz[alpha]anthracene, aflatoxin B1, dimethylnitrosamine, 1,2-dimethylhydrazine, and methylazoxymethanol acetate into chemical species that bind to cellular DNA and protein....

  7. Voorstel voor de humaan-toxicologische onderbouwing van C-(toetsings)waarden. Betreft addendum op rapport 725201005

    OpenAIRE

    Vermeire TG

    1993-01-01

    This report is an addendum to report no 725201005, in which human toxicological guideline values and daily intakes for man are derived based on of a search of the toxicological literature in order to derive C-values for soil. Maximum tolerable risk levels for the total intake of genotoxic carcinogens and toxicologically tolerable daily intakes for threshold compounds have been determined for the following compounds or groups of chemically related compounds: sulfides, anthracene, naphthalene, ...

  8. Prepubertal exposure to cow’s milk reduces susceptibility to carcinogen-induced mammary tumorigenesis in rats

    OpenAIRE

    Nielsen, Tina S.; Khan, Galam; Davis, Jennifer; Michels, Karin B; Hilakivi-Clarke, Leena

    2011-01-01

    Cow’s milk contains high levels of estrogens, progesterone and insulin-like growth factor 1 (IGF-1), all of which are associated with breast cancer. We investigated whether prepubertal milk exposure affects mammary gland development and carcinogenesis in rats. Sprague Dawley rats were given either whole milk or tap water to drink from postnatal day (PND) 14 to PND 35, and thereafter normal tap water. Mammary tumorigenesis was induced by administering 7,12-dimethylbenz[a]anthracene (DMBA) on P...

  9. Inverse Secondary Deuterium Kinetic Isotope Effect in Diels-Alder Reaction of Orthonaphtho [3.3] orthoanthracenophane with Maleic Anhydride

    OpenAIRE

    Mataka, Shuntaro; Ma, Jiang; Tsuzuki, Hirohisa; Nishiyama, Kozaburo; Thiemann, Thies; Tashiro, Masashi

    1996-01-01

    The Diels-Alderreactions of rigid [3.3] orthoanthracenophanes 1 and 2 with maleic anhydride and deuterium-labeled maleic anhydride-d_2, were studied. In the reaction of naphtophane 1, a large inverse secondary kinetic isotope effect (SDKIE) (kH_2/kD_2=0.78) was observed, while benzophane 2 shows a SDKIE similar to that of anthracene itself (kH_2/kD_2=0.95 and 0.96).

  10. Occurrence of Nitro-PAH in the Atmosphere in a Rural Area

    DEFF Research Database (Denmark)

    Nielsen, Tom; Seitz, B.; Ramdahl, T.

    1984-01-01

    By means of gas chromatography with nitrogen sensitive detection and negative ion chemical ionization mass spectrometric detection 7 mononitro-PAH, 9-nitroanthracene, x-nitro-4,5-methylene-phenanthrene, 3-nitrofluoranthene, 1- and 2-nitropyrene, 10-nitrobenz(a)anthracene and 6-nitrobenzo-(a)pyren......-nitroanthracene can be transformed during sampling at low atmospheric concentrations of NO2 and photochemical oxidants to 9,10-dinitroanthracene and 10-nitroanthrone....

  11. Protective Effect of Withaferin-A on Micronucleus Frequency and Detoxication Agents During Experimental Oral Carcinogenesis

    OpenAIRE

    Panjamurthy, Kuppusamy; Manoharan, Shanmugam; Balakrishnan, Subramanian; Suresh, Kathiresan; Nirmal, Madhavan R; Senthil, Namasivayam; Alias, Linsa Marry

    2008-01-01

    Our aim was to investigate the effect of Withaferin-A on bone marrow micronucleus frequency and buccal mucosa detoxication agents during 7, 12-dimethylbenz[a]anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Oral squamous cell carcinoma was developed in hamsters' buccal pouches by painting 0.5% DMBA in liquid paraffin, three times per week for 14 weeks. We observed 100% tumor formation in DMBA painted hamsters. Elevated frequency of bone marrow micronucleated polychromatic erythr...

  12. Photoinduced electron transfer in porous organic salt crystals impregnated with fullerenes.

    Science.gov (United States)

    Hasegawa, Tetsuya; Ohkubo, Kei; Hisaki, Ichiro; Miyata, Mikiji; Tohnai, Norimitsu; Fukuzumi, Shunichi

    2016-06-28

    Porous organic salt (POS) crystals composed of 9-(4-sulfophenyl)anthracene (SPA) and triphenylmethylamine (TPMA) were impregnated with fullerenes (C60 and C70), which were arranged in one dimensional close contact. POS crystals of SPA and TPMA without fullerenes exhibit blue fluorescence due to SPA, whereas the fluorescence was quenched in POS with fullerenes due to electron transfer from the singlet excited state of SPA to fullerenes. PMID:27182038

  13. Molecular modeling study of intercalation complexes of tricyclic carboxamides with d(CCGGCGCCGG) and d(CGCGAATTCGCG)

    OpenAIRE

    Varvaresou, Athanasia; Iakovou, Kriton

    2010-01-01

    Abstract Tricyclic dyes with different mesoatoms such as xanthenes (fluorescein, eosin) anthracenes and acridines (proflavine) approved by the Food and Drug Administration (FDA) for use in foods, pharmaceuticals and cosmetic preparations interact with DNA, and some of them do so through intercalation. Hyperchem 7.5, Spartan 04, Yasara 10.5.14 program packages and molecular modeling, molecular mechanics and dynamics techniques with the oligonucleotides d(CCGGCGCCGG)2 and d(CGCGAATTC...

  14. Bacterial Community Dynamics and Biodegradation Rates in Untreated and Oily Soils During PAH Exposure

    International Nuclear Information System (INIS)

    The approach taken in this study represents an attempt to address the possible selective effects of Polycyclic aromatic hydrocarbons (PAH) on the bacterial community structure of an untreated garden soil (S) and a chronically contaminated oily soil (CS). Untreated and chronically hydrocarbon polluted soils, collected from Egypt were enriched in shaking flasks containing 50 mg/l anthracene as a sole source of carbon over a period of 15 days. Bacterial communities in each soil were profiled by denaturing gradient gel electrophoresis (DGGE) analysis of the PCR amplified 16 S r DNA gene fragments after 0, 5, 10, and 15 days. Culture able biodegrading bacterial counts on minerals- Silica gel- Oil (MSD) plates as well as anthracene degradation for both soils were followed up at the same time intervals. Nine bacterial species were found to be dominant in the pristine soil before enrichment with the model polycyclic aromatic hydrocarbon (PAH), eight of them disappeared after live days of enrichment with the domination of one new species. It stayed dominant in soil until 15 days - exposure to anthracene. Therefore it can be used as a bio marker for PAH pollution. The chronically contaminated soil revealed a remarkable increase in the diversity directly after 5 days exposure to PAH HPLC analysis of the extracted anthracene remained in the biodegradation flasks after different degradation periods revealed that a higher biodegradation rates were accomplished by the oily soil consortium rather than by the pristine one. Before exposure to PAH, counts of culture able biodegrading bacteria were found to be higher in the untreated soil rather than in the oily one. After exposure the situation has been a bit altered as the counts in the untreated soil revealed a temporary suppression with a prolongation of the time required for growth as a result of the hydrocarbon stress

  15. In vitro biosynthesis of the C-glycosidic bond in aloin.

    Science.gov (United States)

    Grün, M; Franz, G

    1981-10-01

    Biosynthetic studies with cell-free extracts from Aloe arborescens Mill. demonstrate the transfer of the glucose moiety from UDP-glucose to aloe emodin anthrone, forming the C-glycosidic linkage in the anthracene derivative aloin. The pH-dependence and the specificity of UDP-glucose and aloe emodin anthrone for the biosynthesis of the C-glycosidic bond in aloin are shown. PMID:24301161

  16. Hepatotoxicity induced by the anti-oxidant food additive, butylated hydroxytoluene BHT, in rats. An electron microscopical study

    OpenAIRE

    Safer, A.M.; Al-Nughamish, A.J.

    1999-01-01

    The anti-oxidant food additive, butylated hydroxytoluene (BHT), was fed to Sprague-Dawley rats at three concentrations: 0.2%, 0.4% and 0.8% for periods of 6, 12, 18 and 24 weeks, and the results were compared with corresponging groups treated with a potent carcinogen, 7,12-dimethylbenz[a]anthracene (DMBA) groups, with olive oil, and with untreated control groups. BHT resulted in a significant increase in liver weight. The liver cells presented gradual vacuo...

  17. Assessment of cancer and noncancer health risks from exposure to PAHs in street dust in the Tamale Metropolis, Ghana.

    Science.gov (United States)

    Obiri, Samuel; Cobbina, Samuel J; Armah, Frederick A; Luginaah, Isaac

    2013-01-01

    This study is part of a broader initiative to characterize, quantify and assess the human health risk associated with exposure to polycyclic aromatic hydrocarbons (PAHs) in street dust along the Trans-ECOWAS highway in West Africa. In the first part, PAHs were characterized and quantified in low- and high-traffic zones. In this study, cancer and noncancer human health risks from exposure to (PAHs) in street dust in the Tamale metropolis, Ghana were assessed in accordance with the USEPA risk assessment guidelines. The results of the study as obtained from inhalation of benzo [a] anthracene (BaA), benzo [a] pyrene (BaP), benzo [k] fluoranthene (BkF) and chrysene via central tendency exposure parameters (CTE) by trespassers (street hawkers including children and adults) in street dust within low traffic zones in the Tamale metropolis are 1.6E-02, 4.7E-02, 1.8E-03, and 1.6E-04 respectively. For reasonable maximum exposure parameters (RME), risk values of 1.2E-01, 3.5E-01, 1.3E-02 and 1.2E-03 respectively were obtained for benzo [a] anthracene, benzo [a] pyrene, benzo [k] fluoranthene and chrysene. Hazard index for acenaphthene, anthracene, fluoranthene, fluorine, naphthalene and pyrene in the CTE and RME scenarios were 2.2, 3.E-01, 2.6, 2.6, 100, 38 and 12, 1.7,15, 14, 550, 210 respectively. Generally, the cancer health risk associated with inhalation of benzo [a] anthracene, benzo [a] pyrene, benzo [k] fluoranthene and chrysene revealed that resident adults and children in the Tamale metropolis are at risk from exposure to these chemicals. The results of this preliminary assessment that quantified PAH related health risks along this part of the Trans-ECOWAS highway revealed that, there is the need for regulatory agencies to put in comprehensive measures to mitigate the risks posed to these categories of human receptors.

  18. In vivo nonlinear spectral imaging as a tool to monitor early spectroscopic and metabolic changes in a murine cutaneous squamous cell carcinoma model

    OpenAIRE

    Thomas, Giju; van Voskuilen, Johan; Truong, Hoa; Song, Ji-Ying; Gerritsen, Hans C.; Sterenborg, H. J. C. M.

    2014-01-01

    Timely detection of cutaneous squamous cell carcinoma with non-invasive modalities like nonlinear spectral imaging (NLSI) can ensure efficient preventive or therapeutic measures for patients. In this study, in vivo NLSI was used to study spectral characteristics in murine skin treated with 7, 12-dimethylbenz(a)anthracene. The results show that NLSI could detect emission spectral changes during the early preclinical stages of skin carcinogenesis. Analyzing these emission spectra using simulate...

  19. Inclusion property and Diels-Alder reaction of bis (diphenyl-phosphine oxide) butadiyne

    Institute of Scientific and Technical Information of China (English)

    LI, Ming-Xia(李明霞); LI, Jin-Liang(李金亮); WANG, Yong-Mei(王永梅); MENG, Ji-Ben(孟继本)

    2000-01-01

    The host molecule, bis( diphenylphosphine oxide ) butadiyne (2), includes a variety of guests to form five complexes (2a-2e). In addition, the Diels-Alder reaction between 2 and anthracene gives 9, 9', 10, 10'-tetrahedron-9, 9', 10, 10'-bi-ethenoantracene- 11, 11'-bis ( diphenylphosphine oxide ) ( 3 )which is a potential di-π-methane reactant and can undergo photorearrangement.

  20. Environmental Remediation: Removal of polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Nkansah, Marian Asantewah

    2012-11-15

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous persistent semi-volatile organic compounds. They are contaminants that are resistant to degradation and can remain in the environment for long periods due to their high degree of conjugation, and aromaticity. PAHs are present in industrial effluents as products of incomplete combustion processes of organic compounds. Petroleum, coal and shale oil contain extremely complex mixtures of these PAHs, and their transport and refining process can also result in the release of PAHs. It is therefore prudent that such effluents are treated before discharge into the environment. In this project, different approaches to the treatment of PAHs have been investigated. Hydrous pyrolysis has been explored as a potential technique for degrading PAHs in water using anthracene as a model compound. The experiments were performed under different conditions of temperature, substrate, redox systems and durations. The conditions include oxidising systems comprising pure water, hydrogen peroxide and Nafion-SiO2 solid catalyst in water; and reducing systems of formic acid and formic acid / Nafion-SiO2 / Pd-C catalysts to assess a range of reactivities. Products observed in GCMS analysis of the extract from the water phase include anthrone, anthraquinone, xanthone and multiple hydro-anthracene derivatives (Paper I). In addition a modified version of the Nafion-SiO2 solid catalyst in water oxidising system was tested; and reducing systems of formic acid and formic acid / Nafion-SiO2 / Pd-C catalysts were adopted for the conversion of a mixture of anthracene, fluorene and fluoranthene. The rate of conversion in the mixture was high as compared to that of only anthracene (Paper II). Also the use of LECA (Lightweight expanded clay aggregates) as an adsorbent (Paper III) for PAHs (phenanthrene, fluoranthene and pyrene) removal from water has been.(Author)

  1. Preclinical evaluation of marketed sodium channel blockers in a rat model of myotonia discloses promising antimyotonic drugs

    OpenAIRE

    Desaphy, Jean-François; Carbonara, Roberta; Costanza, Teresa; Conte Camerino, Diana

    2014-01-01

    Although the sodium channel blocker mexiletine is considered the first-line drug in myotonia, some patients experiment adverse effects, while others do not gain any benefit. Other antimyotonic drugs are thus needed to offer mexiletine alternatives. In the present study, we used a previously-validated rat model of myotonia congenita to compare six marketed sodium channel blockers to mexiletine. Myotonia was induced in the rat by injection of anthracen-9-carboxylic acid, a muscle chloride chann...

  2. Polycyclic aromatic hydrocarbon degradation by the white rot fungus Bjerkandera sp. strain BOS55.

    OpenAIRE

    Kotterman, M.J.J.

    1998-01-01

    Outline of this thesisIn this thesis the conditions for optimal PAH oxidation by the white rot fungus Bjerkandera sp. strain BOS55 were evaluated. In Chapter 2, culture conditions like aeration and cosubstrate concentrations, which influenced the oxidation of the PAH compound anthracene and the ligninolytic indicator dye Poly R-478 by the white rot fungus, were studied. Two parameters were identified as the most important PAH oxidation rate-limiting factors: the hydrogen peroxide production r...

  3. Impact of Inoculation Protocols, Salinity, and pH on the Degradation of Polycyclic Aromatic Hydrocarbons (PAHs) and Survival of PAH-Degrading Bacteria Introduced into Soil

    OpenAIRE

    Kästner, Matthias; Breuer-Jammali, Maren; Mahro, Bernd

    1998-01-01

    Degradation of polycyclic aromatic hydrocarbons (PAHs) and survival of bacteria in soil was investigated by applying different inoculation protocols. The soil was inoculated with Sphingomonas paucimobilis BA 2 and strain BP 9, which are able to degrade anthracene and pyrene, respectively. CFU of soil bacteria and of the introduced bacteria were monitored in native and sterilized soil at different pHs. Introduction with mineral medium inhibited PAH degradation by the autochthonous microflora a...

  4. Implications of treating water containing polynuclear aromatic hydrocarbons with chlorine: a gas chromatographic-mass spectrometric study.

    OpenAIRE

    Oyler, A R; Liukkonen, R J; Lukasewycz, M K; Cox, D A; Peake, D A; Carlson, R M

    1982-01-01

    The products of aqueous chlorination reactions of 1-methylnaphthalene, fluorene, dibenzofuran, anthracene, phenanthrene, 1-methylphenanthrene, fluoranthene, and pyrene have been determined. The conditions employed for these reactions approximated those that might be encountered in water treatment facilities. Reactions at pH greater than 6 tended to produce oxygenated products (epoxides, phenols, quinones, etc.), and reactions at pH less than 6 tended to produce both oxygenated (quinones) and ...

  5. Detection and characterization of human serum antibodies to polycyclic aromatic hydrocarbon diol-epoxide DNA adducts.

    OpenAIRE

    Newman, M J; Light, B A; Weston, A; Tollurud, D; Clark, J L; Mann, D L; Blackmon, J P; Harris, C C

    1988-01-01

    The presence of serum antibodies to the diol-epoxide DNA adducts of representative polycyclic aromatic hydrocarbons (PAH), chrysene, benz[a]anthracene and benzo[a]pyrene, was determined by ELISA using serum samples obtained from normal healthy individuals. Antibodies that reacted against PAH adducted-DNA, but not against PAH-adducted protein, were found in the serum of approximately 40% of the test individuals. Specificity analysis of the antibodies demonstrated that serological cross-reactio...

  6. Molecular-shape-controlled photovoltaic performance probed via soluble {pi}-conjugated arylacetylenic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Seri, Mirko; Marrocchi, Assunta; Taticchi, Aldo [Department of Chemistry, University of Perugia, Via Elce di Sotto 8, 06123 Perugia (Italy); Bagnis, Diego; Ponce, Rocio; Marks, Tobin J.; Facchetti, Antonio [Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois (United States); Argonne-Northwestern Solar Energy Research Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois (United States); Materials Research Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois (United States)

    2011-09-01

    The synthesis and characterization of a new series of anthracene-based derivatives and their use as donors in bulk-heterojunction solar cells is reported. It is found that when using well-defined building blocks in constructing the chromophore, the donor molecular shape dramatically affects organic photovoltaic (OPV) performance in a previously unrecognized way. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Synthesis and modification of reduced graphene oxide aerogels for biofuel cell applications

    Directory of Open Access Journals (Sweden)

    Kondratowicz Izabela

    2015-06-01

    Full Text Available We have carried out the preparation of reduced graphene oxide aerogels using eco-friendly method that is based on the Hummers method of graphite oxidation without the use of NaNO3 that produces toxic gases. To obtain a porous 3D structure of reduced graphene oxide, we performed the hydrothermal reduction at elevated temperature. We also prepared the rGO aerogel/CNT composite using multiwalled carbon nanotubes as linkers. The rGO aerogels are promising materials as they possess good electrical conductivity (up to 100 S/m and high surface area and porous structure (~500 m2/g. The main goal was to obtain the material for electrodes in enzymatic biofuel cells. Thus, the proper modification was performed using free radical functionalization. It was shown that in order to synthesize rGO aerogels modified with anthracene, the proper order of reactions needs to be provided. The morphology of anthracene modified electrodes was analyzed using scanning electron microscopy, which confirmed their porous structure with non-uniform pore size distribution that ranged between few nanometers to microns. Data obtained by Raman spectroscopy confirmed the successful oxidation and reduction of analyzed materials. UV-Vis spectra revealed the presence of anthracene moieties in examined materials. We also recorded preliminary cyclic voltammograms that confirm an electric conductivity of the obtained structures.

  8. Carbon nanorings with inserted acenes: breaking symmetry in excited state dynamics.

    Science.gov (United States)

    Franklin-Mergarejo, R; Alvarez, D Ondarse; Tretiak, S; Fernandez-Alberti, S

    2016-01-01

    Conjugated cycloparaphenylene rings have unique electronic properties being the smallest segments of carbon nanotubes. Their conjugated backbones support delocalized electronic excitations, which dynamics is strongly influenced by cyclic geometry. Here we present a comparative theoretical study of the electronic and vibrational energy relaxation and redistribution in photoexcited cycloparaphenylene carbon nanorings with inserted naphthalene, anthracene, and tetracene units using non-adiabatic excited-state molecular dynamics simulations. Calculated excited state structures reflect modifications of optical selection rules and appearance of low-energy electronic states localized on the acenes due to gradual departure from a perfect circular symmetry. After photoexcitation, an ultrafast electronic energy relaxation to the lowest excited state is observed on the time scale of hundreds of femtoseconds in all molecules studied. Concomitantly, the efficiency of the exciton trapping in the acene raises when moving from naphthalene to anthracene and to tetracene, being negligible in naphthalene, and ~60% and 70% in anthracene and tetracene within the first 500 fs after photoexcitation. Observed photoinduced dynamics is further analyzed in details using induced molecular distortions, delocatization properties of participating electronic states and non-adiabatic coupling strengths. Our results provide a number of insights into design of cyclic molecular systems for electronic and light-harvesting applications. PMID:27507429

  9. Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction.

    Science.gov (United States)

    Pena, M Teresa; Pensado, Luis; Casais, M Carmen; Mejuto, M Carmen; Cela, Rafael

    2007-04-01

    A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 microg kg(-1) dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials. PMID:17268774

  10. MONITORING POLYNUCLEAR AROMATIC HYDROCARBONS IN SEDIMENT POREWATER BY SPMD

    Institute of Scientific and Technical Information of China (English)

    朱亚先; 张勇; 庄一廷; Ka-FaiPoon; MichaelH.W.Lam; 洪华生; RudolfS.S.Wu

    2001-01-01

    A new mimic biological Semi-permeable Membrane Device (SPMD) introduced for sampling organic pollutants yielded satisfactory results when it was frrst used as a passive sampler to concentrate and determine 16 kinds of polynuclear aromatic hydrocarbons (PAHs) by means of capillary GC on an HP 5890 GC-FID in coastal sediment perewater. The concentration of PAHs in sediment porewater for naphthalene(N), acenaphthlene(AL), acenaphthene (AE), fluorene (F), phenaphthene(P), anthracene(A), fluoranthene(FA), pyrene(Py), benzo[a]anthracene(B[a]A), chrysene(Chr), benzo[b] fluor- anthene(B[b]F), benzo[k]fluoranthene(B[k]F), benzo[a]pyrene(B[a]P),indeno[1,2,3,-cd]-Pyrene(I[123]P), dibenz[a,h]anthracene(D[ab]A) and benzo[g,h,i] perylene(B[ghi]P) were:50.36, under detection limits(UD), 18.19, 8.41, 8.40, 1.44, UD, 8.01, 524.15, 168.47, 50.13,123.66, 63.48, 27.40, 82.04 and 58,81 ng/L, respectively.

  11. Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction

    Energy Technology Data Exchange (ETDEWEB)

    Pena, M.T.; Pensado, Luis; Casais, M.C.; Mejuto, M.C.; Cela, Rafael [Universidad de Santiago de Compostela, Dpto. Quimica Analitica, Nutricion y Bromatologia. Instituto de Investigacion y Analisis Alimentario, Santiago de Compostela (Spain)

    2007-04-15

    A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 {mu}g kg{sup -1} dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials. (orig.)

  12. Comparison of polycyclic aromatic hydrocarbons level between suspended solid and sediment samples of Pengkalan Chepa River, Kelantan state, Malaysia

    Science.gov (United States)

    Muslim, Noor Zuhartini Md; Babaheidari, Seyedreza Hashemi; Zakaria, Mohamad Pauzi

    2015-09-01

    Sixteen type of common Polycyclic Aromatic Hydrocarbons (PAHs) which consist of naphthalene, acenaphthene, acenaphthylene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]-perylene, indeno[1,2,3-cd]-pyrene and dibenz[a,h]-anthracene in suspended solid and sediment samples of Pengkalan Chepa River, Kelantan state, Malaysia were investigated. The analysis samples were taken from six different sites of Pengkalan Chepa River during sunny day. The samples were subjected to a series of pre-treatment before the level of PAHs can be determined. A Gas Chromatography-Mass Spectrometry (GC-MS) was the prime method for the analysis of PAHs level. A total of 16 PAHs concentration in suspended solid of the whole Pengkalan Chepa River was found to be 2144.6 ng/g dry weights. This concentration was about eight times more than 16 PAHs concentration in sediment which found to be 266.5 ng/g dry weights.

  13. Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction.

    Science.gov (United States)

    Pena, M Teresa; Pensado, Luis; Casais, M Carmen; Mejuto, M Carmen; Cela, Rafael

    2007-04-01

    A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 microg kg(-1) dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials.

  14. Biodegradation of polycyclic aromatic hydrocarbons by arbuscular mycorrhizal leek plants

    Energy Technology Data Exchange (ETDEWEB)

    Liu, A.; Dalpe, Y. [Agriculture Canada, Ottawa, ON (Canada). Grain and Oilseeds Branch

    2005-07-01

    A study was conducted to examine the response of arbuscular mycorrhizal fungi (AMF) on the degradation of polycyclic aromatic hydrocarbon (PAH), nutrient uptake, and leek growth under greenhouse conditions. This experiment included 3 mycorrhizal treatments, 2 microorganism treatments, 2 PAH chemicals, and 4 concentrations of PAHs. Plant growth was greatly reduced by the addition of anthracene or phenanthrene in soil, whereas mycorrhizal inoculation not only increased plant growth, but also enhanced uptake of nitrogen and phosphorus. PAH concentrations in soil was lowered through the inoculation of two different strains of the species G. intraradices and G. versiforme. In 12 weeks of pot cultures, anthracene and phenanthrene concentrations decreased for all 3 PAH levels tested. However, the reduced amount of phenanthrene in soil was greater than that of anthracene. The addition of a soil microorganism extract into pot cultures accelerated the PAH degradation. The inoculation of AMF in a hydrocarbon contaminated soil was shown to enhance PAHs soil decontamination. It was concluded that a soil colonized with AMF can not only improve plant growth but can also stimulate soil microflora abundance and diversity. AMF may therefore directly influence PAH soil decontamination through plant growth enhancement.

  15. UV-induced changes in humic acid and its effects on PAH phototoxicity to aquatic macrophytes

    Energy Technology Data Exchange (ETDEWEB)

    Gensemer, R.W.; Caggiano, M. [Boston Univ., MA (United States)

    1995-12-31

    The authors are using both photosynthetic biomarkers and population-level endpoints to examine the extent and mechanisms by which humic acid ameliorates the toxicity of the polycyclic aromatic hydrocarbon (PAH) anthracene to the aquatic macrophyte Lemna gibba. Toxicity bioassays using anthracene were run in the presence of 0, 2.5, 5 and 10 mg{center_dot}L{sup {minus}1} of a commercial humic acid which was pretreated to remove insoluble materials. Because UV light significantly affects both PAH toxicity and, potentially, the protective effects of humic acid, plants were incubated both under visible light and under simulate solar radiation (SSR) which mimics the relative UV levels found in natural sunlight. Population-level responses from static-renewal toxicity bioassays were compared to physiological responses determined using plant chlorophyll content and chlorophyll fluorescence induction assays performed at various times throughout the exposure period. Results suggested that humic acid ameliorated the inhibitory effects of anthracene by significantly increasing population growth- and chlorophyll-based EC50 values. This was true both when experiments were performed in visible and SSR, although the inhibitory effects of the PAHs were more pronounced in the presence of UV light. UV also tended to diminish the capability of HA to ameliorate PAH toxicity, presumably owing to photooxidized changes in the ability of HA to control bioavailability.

  16. A study of planar anchor groups for graphene-based single-molecule electronics.

    Science.gov (United States)

    Bailey, Steven; Visontai, David; Lambert, Colin J; Bryce, Martin R; Frampton, Harry; Chappell, David

    2014-02-01

    To identify families of stable planar anchor groups for use in single molecule electronics, we report detailed results for the binding energies of two families of anthracene and pyrene derivatives adsorbed onto graphene. We find that all the selected derivatives functionalized with either electron donating or electron accepting substituents bind more strongly to graphene than the parent non-functionalized anthracene or pyrene. The binding energy is sensitive to the detailed atomic alignment of substituent groups over the graphene substrate leading to larger than expected binding energies for -OH and -CN derivatives. Furthermore, the ordering of the binding energies within the anthracene and pyrene series does not simply follow the electron affinities of the substituents. Energy barriers to rotation or displacement on the graphene surface are much lower than binding energies for adsorption and therefore at room temperature, although the molecules are bound to the graphene, they are almost free to move along the graphene surface. Binding energies can be increased by incorporating electrically inert side chains and are sensitive to the conformation of such chains.

  17. Metabolism and macromolecular binding of benzo(a)pyrene and its noncarcinogenic isomer benzo(e)pyrene in cell culture

    Energy Technology Data Exchange (ETDEWEB)

    Selkirk, J.K.; MacLeod, M.C.

    1978-01-01

    The carcinogenicity of the polycyclic aromatic hydrocarbon benzo(a)pyrene (B(a)P) is thought to result from the metabolic formation of a highly reactive intermediate, 7,8-dihydrodiol-9,10-oxy-B(a)P which subsequently interacts with cellular macromolecules to produce neoplasia. Evidence has been presented implicating similar bay-region diol-epoxides as the ultimate carcinogenic forms of benz(a)anthracene, 7-methyl-benz(a)anthracene, dibenz(a,h)anthracene, and chrysene. Benzo(e)pyrene (B(e)P), on the other hand, is relatively inert when tested for carcinogenicity on mouse skin and rat trachea and when tested for mutagenicity in a mammalian system. This B(e)P molecule contains two (equivalent) bay regions and quantum mechanical model calculations suggest that 9,10-dihydrodiol-11,12-oxy-B(e)P can easily form a reactive bay-region-adjacent carbonium ion. In order to explain the noncarcinogenicity of B(e)P in the context of the bay region theory, we have studied the metabolism of B(e)P by rat liver microsomes and by cultured hamster embryo fibroblasts. In both systems, the major metabolic pathways involve the K-region of B(e)P, with little or no attack on the isolated benzo ring. These results suggest that the lack of carcinogenicity of B(e)P may reflect its preferred mode of interaction with the cellular metabolic machinery.

  18. Rearrangement of cyclotriveratrylene (CTV) diketone: 9,10-diarylanthracenes with OLED applications.

    Science.gov (United States)

    Sarsah, Samuel R S; Lutz, Marlon R; Zeller, Matthias; Crumrine, David S; Becker, Daniel P

    2013-03-01

    Electroluminescent 9,10-diaryl anthracenes have been shown to be promising host and hole-transporting materials in organic electroluminescence due to their high thermal stability, electrochemical reversibility, and wide band gap useful for organic light-emitting diodes (OLEDs), especially blue OLEDs. Oxidation of cyclotriveratrylene (CTV) to the corresponding diketone and subsequent bromination resulted in an unexpected rearrangement to a highly functionalized 9-aryl-10-bromoanthracene derivative, which was employed in Suzuki couplings to synthesize a series of 9,10-diaryl compounds that are structural analogues of anthracene derivatives used in the preparation of OLEDs but are more highly functionalized, including electron-donating methoxy groups in addition to substitution by a carboxylic acid moiety. The UV/fluorescence solution spectra show strong emissions at 446, 438, and 479 nm, respectively, for the anthracene 10-phenyl, 10-naphthyl, and 10-pyrenyl adducts containing a benzoic acid functional group, whereas the analogues bearing the hydroxymethylene moiety from reduction of the benzoic acid to the corresponding alcohols gave much shorter emission wavelengths of 408, 417, and 476 nm, respectively, and had somewhat higher quantum yields, suggesting they are better candidates for OLED applications. PMID:23190432

  19. Carbon nanorings with inserted acenes: breaking symmetry in excited state dynamics

    Science.gov (United States)

    Franklin-Mergarejo, R.; Alvarez, D. Ondarse; Tretiak, S.; Fernandez-Alberti, S.

    2016-08-01

    Conjugated cycloparaphenylene rings have unique electronic properties being the smallest segments of carbon nanotubes. Their conjugated backbones support delocalized electronic excitations, which dynamics is strongly influenced by cyclic geometry. Here we present a comparative theoretical study of the electronic and vibrational energy relaxation and redistribution in photoexcited cycloparaphenylene carbon nanorings with inserted naphthalene, anthracene, and tetracene units using non-adiabatic excited-state molecular dynamics simulations. Calculated excited state structures reflect modifications of optical selection rules and appearance of low-energy electronic states localized on the acenes due to gradual departure from a perfect circular symmetry. After photoexcitation, an ultrafast electronic energy relaxation to the lowest excited state is observed on the time scale of hundreds of femtoseconds in all molecules studied. Concomitantly, the efficiency of the exciton trapping in the acene raises when moving from naphthalene to anthracene and to tetracene, being negligible in naphthalene, and ~60% and 70% in anthracene and tetracene within the first 500 fs after photoexcitation. Observed photoinduced dynamics is further analyzed in details using induced molecular distortions, delocatization properties of participating electronic states and non-adiabatic coupling strengths. Our results provide a number of insights into design of cyclic molecular systems for electronic and light-harvesting applications.

  20. SYNTHESIS OF FUNCTIONAL MACROMOLECULE INTERMEDIATE THROUGH ACYLATION CATALYZED BY [Emim]Cl-AlCl3 IONIC LIQUID

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]C1-A1C13 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer material, was obtained by recrystalling the reaction mixture with aether and was determined by GC/MS, 1HNMR and FTIR analysis. The influences of various parameters, such as the contents of AlCl3 in [Emim]C1-A1C13, the amount of acylation agent, amount of [Emim]C1-A1C13, reaction temperature and reaction time were investigated. The optimum conditions were as follows: the molar fraction of A1C13 in ionic liquid [x(AlCl3)] being 0.67 , molar ratio of ionic liquid to anthracene being 2:1 , molar ratio of oxalyl chloride to anthracene being 2:1, reaction temperature being 40℃ and reaction time being 6h. Under above conditions, the yield and selectivity of 1,2-aceanthrylenedione can reach 91.5% and 98.3% respectively. Further more, [Emim]C1-A1C13 ionic liquid, compared with metal halides such as AlCl3, was found to catalyze the reaction as a novel environmental friendly catalyst and solvent and can be reused.

  1. SYNTHESIS OF FUNCTIONAL MACROMOLECULE INTERMEDIATE THROUGH ACYLATION CATALYZED BY [Emim]Cl-AlCl3 IONIC LIQUID

    Institute of Scientific and Technical Information of China (English)

    CHEN Min; JIANG Deli; ZHANG Chunyan; YU Long; YAN Yongsheng

    2007-01-01

    Acylation reaction of anthracene with oxalyl chloride in the presence of [Emim]Cl-AlCl3 ionic liquid has been investigated. Pure 1,2-aceanthryenedione, which is used as intermediate of functional aromatic polymer material, was obtained by recrystalling the reaction mixture with aether and was determined by GC/MS, 1HNMR and FTIR analysis. The influences of various parameters,such as the contents of AlCl3 in [Emim]Cl-AlCl3, the amount of acylation agent, amount of [Emim]Cl-AlCl3, reaction temperature and reaction time were investigated. The optimum conditions were as follows: the molar fraction of AlCl3 in ionic liquid [x(AlCl3)] being 0.67, molar ratio of ionic liquid to anthracene being 2:1, molar ratio of oxalyl chloride to anthracene being 2:1,reaction temperature being 40 ℃ and reaction time being 6h. Under above conditions, the yield and selectivity of 1,2-aceanthrylenedione can reach 91.5% and 98.3% respectively. Further more,[Emim]Cl-AlCl3 ionic liquid, compared with metal halides such as AlCl3, was found to catalyze the reaction as a novel environmental friendly catalyst and solvent and can be reused.

  2. Isolation, fingerprinting and genetic identification of indigenous PAHs degrading bacteria from oil-polluted soils.

    Science.gov (United States)

    Alrumman, Sulaiman A; Hesham, Abd El-Latif; Alamri, Saad A

    2016-01-01

    In the present study, thirty five bacterial isolates were obtained from hydrocarbon-contaminated soil samples using an enrichment method. These isolates were tested to grow on mineral salt medium containing anthracene or phenanthrene as sole carbon source. Only five isolates showed the ability to degrade these compounds. RAPD-PCR fingerprinting was carried out for the five isolates, and the DNA patterns revealed that there was no similarity among the examined bacteria whenever the RFLP using four restriction enzymes HaeIII, Msp1, Hinf1 and Taq1 failed to differentiate among them. Five bacterial isolates were grown in high concentration of anthracene and phenanthrene (4% w/v). Two bacterial isolates were selected due to their high ability to grow in the presence of high concentrations of anthracene and phenanthrene. The isolates were identified as Bacillus flexus and Ochrobactrum anthropi, based on DNA sequencing of amplified 16S rRNA gene and phylogenetic analysis. Finally, the ability of these bacterial strains to tolerate and remove different PAHs looked promising for application in bioremediation technologies. PMID:26930863

  3. Risk Assessment for Children Exposed to Beach Sands Impacted by Oil Spill Chemicals

    Directory of Open Access Journals (Sweden)

    Jennifer C. Black

    2016-08-01

    Full Text Available Due to changes in the drilling industry, oil spills are impacting large expanses of coastlines, thereby increasing the potential for people to come in contact with oil spill chemicals. The objective of this manuscript was to evaluate the health risk to children who potentially contact beach sands impacted by oil spill chemicals from the Deepwater Horizon disaster. To identify chemicals of concern, the U.S. Environmental Protection Agency’s (EPA’s monitoring data collected during and immediately after the spill were evaluated. This dataset was supplemented with measurements from beach sands and tar balls collected five years after the spill. Of interest is that metals in the sediments were observed at similar levels between the two sampling periods; some differences were observed for metals levels in tar balls. Although PAHs were not observed five years later, there is evidence of weathered-oil oxidative by-products. Comparing chemical concentration data to baseline soil risk levels, three metals (As, Ba, and V and four PAHs (benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and dibenz[a,h]anthracene were found to exceed guideline levels prompting a risk assessment. For acute or sub-chronic exposures, hazard quotients, computed by estimating average expected contact behavior, showed no adverse potential health effects. For cancer, computations using 95% upper confidence limits for contaminant concentrations showed extremely low increased risk in the 10−6 range for oral and dermal exposure from arsenic in sediments and from dermal exposure from benzo[a]pyrene and benz[a]anthracene in weathered oil. Overall, results suggest that health risks are extremely low, given the limitations of available data. Limitations of this study are associated with the lack of toxicological data for dispersants and oil-spill degradation products. We also recommend studies to collect quantitative information about children’s beach play habits, which are

  4. Bioremediation of polycyclic aromatic hydrocarbon-contaminated saline-alkaline soils of the former Lake Texcoco.

    Science.gov (United States)

    Betancur-Galvis, L A; Alvarez-Bernal, D; Ramos-Valdivia, A C; Dendooven, L

    2006-03-01

    Polycyclic aromatic hydrocarbons (PAHs) such as phenanthrene, anthracene and Benzo[a]pyrene (BaP) are toxic for the environment. Removing these components from soil is difficult as they are resistant to degradation and more so in soils with high pH and large salt concentrations as in soil of the former lake Texcoco, but stimulating soil micro-organisms growth by adding nutrients might accelerate soil restoration. Soil of Texcoco and an agricultural Acolman soil, which served as a control, were spiked with phenanthrene, anthracene and BaP, added with or without biosolid or inorganic fertilizer (N, P), and dynamics of PAHs, N and P were monitored in a 112-day incubation. Concentrations of phenanthrene did not change significantly in sterilized Acolman soil, but decreased 2-times in unsterilized soil and >25-times in soil amended with biosolid and NP. The concentration of phenanthrene in unsterilized soil of Texcoco was 1.3-times lower compared to the sterilized soil, 1.7-times in soil amended with NP and 2.9-times in soil amended with biosolid. In unsterilized Acolman soil, degradation of BaP was faster in soil amended with biosolid than in unamended soil and soil amended with NP. In unsterilized soil of Texcoco, degradation of BaP was similar in soil amended with biosolid and NP but faster than in the unamended soil. It was found that application of biosolid and NP increased degradation of phenanthrene, anthracene and BaP, but to a different degree in alkaline-saline soil of Texcoco compared to an agricultural Acolman soil.

  5. Content determination and health risk assessment of polycyclic aromatic hydrocarbon in fish tissue samples from Perhentian Island, Malaysia

    International Nuclear Information System (INIS)

    The concentration of polycyclic aromatic hydrocarbon (PAH) in three fish species with different feeding habits and habitat for examples Lolong (Selar boops), Kerisi (Nemipterus peronii) dan Mengkarong (Trachinocephalus myops) from offshore of Perhentian Island, Malaysia was determined. Three individuals from each species were taken at random and the PAHs contents were determined in the muscles. Ten PAH compounds, phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(e)pyrene and dibenzo(a,h)anthracene were determined. PAH in fish tissues was extracted using Soxhlet method and detected using gas chromatography - mass spectrometry (GC-MS). The level of PAH in fish tissue ranged from 17.89 - 42.18 ng/ g wet weight and 393.98 - 511.07 ng/ g lipid weight. The order of PAH concentration in wet weight was Kerisi (511.07 ng/ g)> Mengkarong (409.50 ng/ g)> Lolong (393.98 ng/ g) but in terms of lipid weight, the order was Kerisi (511.07 ng/ g)> Mengkarong (409.50 ng/ g)> Lolong (393.98 ng/ g). Kerisi has the lowest lipid content of 3.5 % compared to Lolong (6.5 %) and Mengkarong (10.3 %). No obvious significant difference (p > 0.05) of PAH levels in three fish species was observed (ANOVA, p > 0.05). There was no significant relationship between lipid content and PAH accumulation in fish. Based on fish consumption rate of 142.2 g/ day, the Potency Equivalent Concentration (PEC), which is a carcinogenic potency value for PAH, was found to be ranged from 0.41 - 0.63 ng/ g wet weight in all three species of fish. This value is below the limit set by USEPA, which is 0.67 ng/ g wet weight for human consumption. (author)

  6. Soil pollution by PAHs in urban soils: a comparison of three European cities.

    Science.gov (United States)

    Morillo, E; Romero, A S; Maqueda, C; Madrid, L; Ajmone-Marsan, F; Grcman, H; Davidson, C M; Hursthouse, A S; Villaverde, J

    2007-09-01

    The purpose of this study was to determine the degree of contamination with polycyclic aromatic hydrocarbons (PAHs) in samples of urban soil from three European cities: Glasgow (UK), Torino (Italy) and Ljubljana (Slovenia). Fifteen PAHs (naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene, indeno[1,2,3-c,d]pyrene) were measured in urban soil samples, using harmonised sampling, sample extraction and analyte quantification methods. Although the mean concentration of each PAH in urban soils of each city showed a wide range of values, high levels of contamination were only evident in Glasgow, where the sum of concentrations of 15 PAHs was in the range 1487-51,822 microg kg(-1), cf. ranges in the other two cities were about ten-fold lower (89.5-4488 microg kg(-1)). The three predominant PAHs were phenanthrene, fluoranthene and pyrene, with the sum of these compounds about 40% of the total PAH content. These data, together with some special molecular indices based on ratios of selected PAHs, suggest pyrogenic origins, especially motor vehicle exhausts, to be the major sources of PAHs in urban soils of the three cities. The largest concentrations for PAHs were often found in sites close to the historic quarters of the cities. Overall, the different climatic conditions, the organic carbon contents of soil, and the source apportionment were the dominant factors affecting accumulation of PAHs in soil. PMID:17726562

  7. Characterization of parent and oxygenated-polycyclic aromatic hydrocarbons (PAHs) in Xi'an, China during heating period: An investigation of spatial distribution and transformation.

    Science.gov (United States)

    Wang, Jingzhi; Hang Ho, Steven Sai; Huang, Rujin; Gao, Meiling; Liu, Suixin; Zhao, Shuyu; Cao, Junji; Wang, Gehui; Shen, Zhenxing; Han, Yongming

    2016-09-01

    Polycyclic aromatic hydrocarbons (PAHs) and its oxygenated derivatives (OPAHs) are toxins in PM2.5. Little information has been known for their transformation in the ambient airs. In this study, PM2.5 samples were collected at 19 sampling sites in Xi'an, China during the heating period, which is classified into: urban residential, university, commercial area, suburban region, and industry. Organic compounds including PAHs, OPAHs, hopanes and cholestanes were quantified. The average of total quantified PAHs and OPAHs concentrations were 196.5 ng/m(3) and 29.4 ng/m(3), respectively, which were consistent with other northern cities in China. Statistical analyses showed that there were significant differences on the distributions of PAHs between urban and suburban regions. The industry also had distinguishable profiles compared with urban residential and commercial area for OPAHs. The greater diversity of OPAHs than PAHs might be due to different primary emission sources and transformation and degradation pathways. The ratios of OPAHs to the corresponding parent PAHs, including 9-fluorenone/fluorene, anthraquinone/anthracene, benz[a]anthracene-7,12-dione/benzo[a]anthracene were 6.2, 12.7, and 1.4, respectively, which were much higher than those for the fresh emissions from coal combustion and biomass burning. These prove the importance of secondary formation and transformation of OPAHs in the ambient airs. Biomarkers such as retene, cyclopenta[CD]pyrene and αα-homohopane were characterized for the source apportionment. With Positive Matrix Factorization (PMF) model analysis, biomass burning was recognized as the most dominant pollution sources for PAHs during the heading period, which accounted for a contribution of 37.1%. Vehicle emission (22.8%) and coal combustion (22.6%) were also contributors in Xi'an. PMID:27323290

  8. Risk Assessment for Children Exposed to Beach Sands Impacted by Oil Spill Chemicals.

    Science.gov (United States)

    Black, Jennifer C; Welday, Jennifer N; Buckley, Brian; Ferguson, Alesia; Gurian, Patrick L; Mena, Kristina D; Yang, Ill; McCandlish, Elizabeth; Solo-Gabriele, Helena M

    2016-01-01

    Due to changes in the drilling industry, oil spills are impacting large expanses of coastlines, thereby increasing the potential for people to come in contact with oil spill chemicals. The objective of this manuscript was to evaluate the health risk to children who potentially contact beach sands impacted by oil spill chemicals from the Deepwater Horizon disaster. To identify chemicals of concern, the U.S. Environmental Protection Agency's (EPA's) monitoring data collected during and immediately after the spill were evaluated. This dataset was supplemented with measurements from beach sands and tar balls collected five years after the spill. Of interest is that metals in the sediments were observed at similar levels between the two sampling periods; some differences were observed for metals levels in tar balls. Although PAHs were not observed five years later, there is evidence of weathered-oil oxidative by-products. Comparing chemical concentration data to baseline soil risk levels, three metals (As, Ba, and V) and four PAHs (benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and dibenz[a,h]anthracene) were found to exceed guideline levels prompting a risk assessment. For acute or sub-chronic exposures, hazard quotients, computed by estimating average expected contact behavior, showed no adverse potential health effects. For cancer, computations using 95% upper confidence limits for contaminant concentrations showed extremely low increased risk in the 10(-6) range for oral and dermal exposure from arsenic in sediments and from dermal exposure from benzo[a]pyrene and benz[a]anthracene in weathered oil. Overall, results suggest that health risks are extremely low, given the limitations of available data. Limitations of this study are associated with the lack of toxicological data for dispersants and oil-spill degradation products. We also recommend studies to collect quantitative information about children's beach play habits, which are necessary to more

  9. Risk Assessment for Children Exposed to Beach Sands Impacted by Oil Spill Chemicals

    Science.gov (United States)

    Black, Jennifer C.; Welday, Jennifer N.; Buckley, Brian; Ferguson, Alesia; Gurian, Patrick L.; Mena, Kristina D.; Yang, Ill; McCandlish, Elizabeth; Solo-Gabriele, Helena M.

    2016-01-01

    Due to changes in the drilling industry, oil spills are impacting large expanses of coastlines, thereby increasing the potential for people to come in contact with oil spill chemicals. The objective of this manuscript was to evaluate the health risk to children who potentially contact beach sands impacted by oil spill chemicals from the Deepwater Horizon disaster. To identify chemicals of concern, the U.S. Environmental Protection Agency’s (EPA’s) monitoring data collected during and immediately after the spill were evaluated. This dataset was supplemented with measurements from beach sands and tar balls collected five years after the spill. Of interest is that metals in the sediments were observed at similar levels between the two sampling periods; some differences were observed for metals levels in tar balls. Although PAHs were not observed five years later, there is evidence of weathered-oil oxidative by-products. Comparing chemical concentration data to baseline soil risk levels, three metals (As, Ba, and V) and four PAHs (benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and dibenz[a,h]anthracene) were found to exceed guideline levels prompting a risk assessment. For acute or sub-chronic exposures, hazard quotients, computed by estimating average expected contact behavior, showed no adverse potential health effects. For cancer, computations using 95% upper confidence limits for contaminant concentrations showed extremely low increased risk in the 10−6 range for oral and dermal exposure from arsenic in sediments and from dermal exposure from benzo[a]pyrene and benz[a]anthracene in weathered oil. Overall, results suggest that health risks are extremely low, given the limitations of available data. Limitations of this study are associated with the lack of toxicological data for dispersants and oil-spill degradation products. We also recommend studies to collect quantitative information about children’s beach play habits, which are necessary to more

  10. Risk Assessment for Children Exposed to Beach Sands Impacted by Oil Spill Chemicals.

    Science.gov (United States)

    Black, Jennifer C; Welday, Jennifer N; Buckley, Brian; Ferguson, Alesia; Gurian, Patrick L; Mena, Kristina D; Yang, Ill; McCandlish, Elizabeth; Solo-Gabriele, Helena M

    2016-08-27

    Due to changes in the drilling industry, oil spills are impacting large expanses of coastlines, thereby increasing the potential for people to come in contact with oil spill chemicals. The objective of this manuscript was to evaluate the health risk to children who potentially contact beach sands impacted by oil spill chemicals from the Deepwater Horizon disaster. To identify chemicals of concern, the U.S. Environmental Protection Agency's (EPA's) monitoring data collected during and immediately after the spill were evaluated. This dataset was supplemented with measurements from beach sands and tar balls collected five years after the spill. Of interest is that metals in the sediments were observed at similar levels between the two sampling periods; some differences were observed for metals levels in tar balls. Although PAHs were not observed five years later, there is evidence of weathered-oil oxidative by-products. Comparing chemical concentration data to baseline soil risk levels, three metals (As, Ba, and V) and four PAHs (benzo[a]pyrene, benz[a]anthracene, benzo[b]fluoranthene, and dibenz[a,h]anthracene) were found to exceed guideline levels prompting a risk assessment. For acute or sub-chronic exposures, hazard quotients, computed by estimating average expected contact behavior, showed no adverse potential health effects. For cancer, computations using 95% upper confidence limits for contaminant concentrations showed extremely low increased risk in the 10(-6) range for oral and dermal exposure from arsenic in sediments and from dermal exposure from benzo[a]pyrene and benz[a]anthracene in weathered oil. Overall, results suggest that health risks are extremely low, given the limitations of available data. Limitations of this study are associated with the lack of toxicological data for dispersants and oil-spill degradation products. We also recommend studies to collect quantitative information about children's beach play habits, which are necessary to more

  11. UVA Photoirradiation of Halogenated-Polycyclic Aromatic Hydrocarbons Leading to Induction of Lipid Peroxidation

    Directory of Open Access Journals (Sweden)

    Peter P. Fu

    2006-06-01

    Full Text Available Since the finding in the 1930s, a large number of polycyclic aromatic hydrocarbons (PAHs of different structures have been tested for potential tumorigenicity. Structure-activity relationships of halo-PAHs have been investigated to determine the regions of a PAH that may be involved in cancer initiation. From these studies, a number of halo-PAHs were found to be tumorigenic in experimental animals. It was not until the 1980s that halo-PAHs were found to be present in the environment, including municipal incinerator fly ash, urban air, coal combustion, soil, snow, automobile exhausts, and tap water. Due to their widespread presence in the environment and their genotoxic activities, including carcinogenicity, many of these compounds may pose a health risk to humans. Although the biological activities, including metabolism, mutagenicity, and carcinogenicity, of halo-PAHs have been studied their phototoxicity and photo-induced biological activity have not been well examined. In this study, we study the photoirradiation of a series of structure-related halo-PAHs by UVA light in the presence of a lipid, methyl linoleate, and determine as to whether or not these compounds can induce lipid peroxidation. The halo-PAHs chosen for study include 2-bromonaphthalene, 1-chloroanthracene, 9,10-dibromoanthracene, 9-chlorophenanthrene, 9-bromophenanthrene, 7-chlorobenz[a]anthracene, 7-bromobenz[a]anthracene, 7-bromo-5-methylbenz[a]anthracene, 6-chlorobenzo[a]pyrene, and 6-bromobenzo[a]pyrene. The results indicate that upon photoirradiation by UVA all these compounds induced lipid peroxidation at different levels. These results suggest that halo-PAHs may be harmful to human health.

  12. Effect of irradiance spectra on the photoinduced toxicity of three polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Diamond, S.A.; Mount, D.R.; Burkhard, L.P.; Ankley, G.T.; Makynen, E.A.; Leonard, E.N.

    2000-05-01

    Photoinduced toxicity of polycyclic aromatic hydrocarbons (PAHs) is dependent on the concentration of compounds present and the dose of light received. Of the light present, only those wavelengths absorbed by the compound have the potential to initiate the photochemical events underlying phototoxicity. This suggests that variation in light spectra present in natural waters, arising from variation in dissolved organic carbon composition, is an important determinant of phototoxicity risk in specific, PAH-contaminated waterbodies. To quantify the effect of environmentally realistic variation in light spectra on toxicity, brine shrimp (Artemia salina) assays were conducted under various light spectra and with three PAHs (pyrene, fluoranthene, and anthracene) of known phototoxicity potential. In these spectral assays, the total ultraviolet light present was equivalent; only the spectral characteristics varied. Based on the absorbance spectra of these PAHs, it was predicted that toxicity, quantified using immobilization as the endpoint, would vary significantly among light spectra in pyrene assays, but not in anthracene assays, and that variation in toxicity in fluoranthene assays would be intermediate. The results supported these assumptions. In the pyrene exposures, the glass filter time to 50% population immobilization (IT50) (39.5 min) was 117% longer than the KCr filter IT50 (18.2 min). In the fluoranthene exposures, the glass filter IT50 (49.5 min) was 27% longer than the KCr filter IT50 (39.1 min). In the anthracene exposures, the glass filter IT50 (62.2 min) was not statistically different from the KCr filter IT50 (63.8 min). Comparison of these results with the results of assays conducted under neutral-density filters (that change intensity but not spectral distribution) demonstrate that multiplying spectral intensity by wavelength-specific absorbance accurately predicts relative photoinduced toxicity among the experimental treatments. These results indicate

  13. A novel analytical approach for visualizing and tracking organic chemicals in plants.

    Science.gov (United States)

    Wild, Edward; Dent, John; Barber, Jonathan L; Thomas, Gareth O; Jones, Kevin C

    2004-08-01

    Vegetation plays a key role in the environmental fate of many organic chemicals, from pesticides applied to plants, to the air-vegetation exchange and global cycling of atmospheric organic contaminants. Our ability to locate such compounds in plants has traditionally relied on inferences being made from destructive chemical extraction techniques or methods with potential artifacts. Here, for the first time, two-photon excitation microscopy (TPEM) is coupled with plant autofluorescence to visualize and track trace levels of an organic contaminant in living plant tissue, without any form of sample modification or manipulation. Anthracene-a polynuclear aromatic hydrocarbon (PAH)-was selected for study in living maize (Zea mays) leaves. Anthracene was tracked over 96 h, where amounts as low as approximately 0.1-10 pg were visible, as it moved through the epicuticular wax and plant cuticle, and was observed reaching the cytoplasm of the epidermal cells. By this stage, anthracene was identifiable in five separate locations within the leaf: (1) as a thin (approximately 5 microm) diffuse layer, in the upper surface of the epicuticular wax; (2) as thick (approximately 28 microm) diffuse bands extending from the epicuticular wax through the cuticle, to the cell walls of the epidermal cells; (3) on the external surface of epidermal cell walls; (4) on the internal surface of epidermal cell walls; and (5) within the cytoplasm of the epidermal cells. This technique provides a powerful nonintrusive tool for visualizing and tracking the movement, storage locations, and degradation of organic chemicals within vegetation using only plant and compound autofluorescence. Many other applications are envisaged for TPEM, in visualizing organic chemicals within different matrixes. PMID:15352460

  14. A Potential Impact on the Chemical Composition in the Marine Boundary Layer in the Arctic Ocean by Ship Emissions

    Science.gov (United States)

    Xie, Z.; Wang, X.; Blum, J. D.; Sun, L.

    2005-12-01

    Samples of aerosols in the marine boundary layer (MBL) of the Arctic Ocean were collected aboard R/V ()Xuelong during the summer on the Second Chinese Arctic Research Expedition (July-September, 2003). Chemical compositions including major and trace elements and polycyclic aromatic hydrocarbons (PAHs) in aerosol particles were analyzed. Results showed that significant amounts of S, Fe, V and Ni are emitted from ship diesel engines and contaminate the ambient air. The total amount of Fe, which plays a significant role in the ocean ()biological pump, emitted from ships in the Arctic is estimated at 4.33-A106 kg yr-1. Sulfur emitted into the atmosphere may be transformed to sulfur acid and result in a chlorine depletion in sea-salt. Because the global inventory of sulfur from ship exhausts is large and halogens may have important consequences in possible tropospheric ozone destruction, the role of ships in effecting halogen depression in sea-salt should be evaluated. For organic compounds, 17 PAHs including Fluoranthene, Phenanthrene, Chrysene, Indeno[123-cd]pyrene, Pyrene, Benzo[b]fluoranthene, Benzo[ghi]pyrene, Naphthalene, Benzo[a]anthracene, Benzo[k]fluoranthene, Coronene, Fluorene, Benzo[a]pyrene, Acenaphthene, Anthracene, Dibenzo[a,h]anthracene and Acenaphthylene were detected. The average levels of subspecies of PAHs in ambient air ranged from 0.003 to 0.089 ng/m3. Among the 17 PAHs, fluoranthene had a relative high level, while the level of acenaphthylene was relative low. The aerosols contaminated by the ship, which were commonly excluded in previous investigations, thus provide an opportunity to investigate and understand the role of ship emissions in the atmospheric chemistry of the marine boundary layer, especially in the Arctic Ocean.

  15. Behaviour of scintillometers with charge particles; Respuesta de detectores de centelleo a particulas cargadas

    Energy Technology Data Exchange (ETDEWEB)

    Vigon, M. A.; Montes, J.; Granados, C. E.; Gutierrez, R.

    1959-07-01

    The behaviour of a scintillation plastic and an anthracene crystal for protons and deuterons with energies within 0,2 and 1,7 MeV. has been studied. The beam of monoenergetic particles falls directly on the detector in study in optic contact with a photomultiplicator. The impulse get in an amplifier which sends then to a scale a sting as a monitor and to an analyzer of 100 canals. The spectrum for each energy of incidental beam is obtained taking the maximum of the spectrum as the most probable value of amplitude of the detector reply, and this is represented apposite to the energy. (Author) 6 refs.

  16. STUDIES OF THE ANTENNA EFFECT IN POLYMER MOLECULES ENERGY MIGRATION AND TRAPPING IN NAPHTHALENE-CONTAINING POLYELECTROLYTES

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Polymers of 1- and 2-vinylnaphthalene containing more than about 50mol% sulfonic acid groups dissolve in water to form "hypercoiled" conformations which have many of the properties of micelles. Hydrophobic molecules such as anthracene and perylene are selectively absorbed in these pseudo micellar structures, and their fluorescence emission is sensitized by energy transfer from the surrounding naphthalene chromophores.When irradiated with UV light in the presence of oxygen, the emission of perylene rapidly decreases. It is proposed that this is due to reaction of singlet oxygen with the perylene trapped in the hypercoiled polymer.

  17. Health assessment for E. H. Schilling Landfill, Ironton, Lawrence County, Ohio, Region 5. CERCLIS No. OHD980509847. Preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    1988-12-02

    The E.H. Schilling Landfill site is listed on the National Priorities List. The five-acre site was a landfill, licensed to accept only nonhazardous dry industrial waste, from 1971 until 1980 when it was closed. The environmental contamination on-site consists of polychlorinated biphenyls, vinyl toluene, cumene, polynuclear aromatic hydrocarbons or PAHs, including fluoranthene, benzo(a)pyrene, and benzo(a)anthracene, in soil. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardous substances via ground water, soil, sediment, surface water, and air.

  18. ADO-phosphonic acid self-assembled monolayer modified dielectrics for organic thin film transistors

    Science.gov (United States)

    Zhefeng, Li; Xianye, Luo

    2014-10-01

    This study explores a strategy of using the phosphonic acid derivative (11-((12-(anthracen-2-yl)dodecyl)oxy)-11-oxoundecyl) phosphonic acid (ADO-phosphonic acid) as self-assembled monolayers (SAMs) on a Si/SiO2 surface to induce the crystallization of rubrene in vacuum deposited thin film transistors, which showed a field-effect mobility as high as 0.18 cm2/(V·s). It is found that ADO-phosphonic acid SAMs play a unique role in modulating the morphology of rubrene to form a crystalline film in the thin-film transistors.

  19. A spectroscopic rule from the solvatochromism of aromatic solutes in nonpolar solvents.

    Science.gov (United States)

    Catalán, Javier; Del Valle, Juan Carlos

    2014-05-15

    The UV-vis absorption spectroscopy for a series of selected symmetrical aromatic hydrocarbons, benzene, naphthalene, anthracene, 9,10-diphenylanthracene, perylene, and rubrene in the gas phase or in 2-methylbutane, shows the consistency of a new spectroscopic rule. From a thorough spectroscopic analysis with temperature variation (293-113 K) this rule states that "an aromatic molecule, on Franck-Condon excitation can hardly generate an excited electronic state with a lower polarizability than that of its ground electronic-state." We have not found any exceptions to this rule. PMID:24735522

  20. A method for the amplification of chemically induced transformation in C3H/10T1/2 clone 8 cells: its use as a potential screening assay.

    Science.gov (United States)

    Schechtman, L M; Kiss, E; McCarvill, J; Nims, R; Kouri, R E; Lubet, R A

    1987-09-01

    A method has been developed by which to amplify expression of phenotypic transformation of C3H/10T1/2 clone 8 mouse embryo cells not otherwise observed in the standard transformation assay. The expression of transformed foci was amplified by subcultivating chemically treated target cells after they had reached confluence and replating them at subconfluent cell densities. Conditions leading to the expression of the highest numbers of transformed foci include a) a cell seeding density for chemical treatment of 1 X 10(4) cells/dish, b) subculture 4 weeks after treatment, and c) replating cells at a density of 2 X 10(5) cells/-dish. Agents capable of inducing transformation in the standard assay (e.g., 4,4'-bis(dimethylamino)benzophenone, benzo[a]pyrene, 7,12-dimethylbenz[a]anthracene, and others) also yielded transformation in the replating assay. The more marginal transforming activities of chemicals such as ethyl methanesulfonate, 7-(bromomethyl)-12-methylbenz[a]anthracene, and N-methyl-N'-nitro-N-nitrosoguanidine were enhanced by the amplification procedure. Compounds that failed to elicit focal transformation in the standard assay (e.g., dibenz[a,h]anthracene, Tris(2,3-dibromopropyl) phosphate, lead acetate, benzidine, propyleneimine, N-hydroxy-2-fluorenylacetamide, and numerous other compounds of various chemical classes) induced significant levels of phenotypic transformation upon amplification. Noncarcinogens (e.g., phenanthrene, anthracene, 2-aminobiphenyl, cycloheximide, and others) failed to cause significant phenotypic transformation even when cells were replated. To further enhance the applicability of this new replating system, an exogenous source of metabolic activation was added: a 9,000 X g supernatant from Aroclor 1254-induced rat hepatic S-9. This activation system was found a) to be only minimally cytotoxic by itself and b) to be able to mediate NADPH-dependent, dose-dependent toxicity, and transformation by activating the procarcinogens

  1. Synthesis and Structure of a Novel Disulfide-Containing Aniline

    Institute of Scientific and Technical Information of China (English)

    DENG,Shi-Ren; WU,Lei; WANG,Hao; ZHOU,Bin; LI,Zao-Ying

    2004-01-01

    @@ A novel disulfide-containing aniline, 8-dihydro-1H,4H-2,3,6,7-tetrathia-anthracen-9-ylamine (5) was synthesized.The single-crystal X-ray analysis of 4 indicates that the molecular has a non-planar structure, with its four sulfur atoms out of the plane of benzene ting. The designed molecular has the advantage of high theoretic specific capacity and reversibility,[1,2] when it is to be polymerized and used as the cathode material of the secondary lithium batteries.

  2. Ultrafast cyclic voltammetry with asymmetrical potential scan

    Institute of Scientific and Technical Information of China (English)

    Zhi Yong Guo; Xiang Qin Lin

    2008-01-01

    Based on the perfect ohmic drop compensation by online electronic positive feedback, ultrafast cyclic voltammetry withasymmetrical potential scan is achieved for the first time, with the reduction of anthracene acting as the test system. Compared withthe traditional cyclic voltammetry utilizing symmetrical triangular waveform as the excitation one, the new method allows a simplerapproach to mechanistic analysis of ultrafast chemical reactions coupled with a charge transfer. And perhaps more important, it alsoprovides a way to eliminate the interference of the adsorbed product in dynamic monitoring.

  3. Palladium(II)-Catalyzed Tandem Synthesis of Acenes Using Carboxylic Acids as Traceless Directing Groups.

    Science.gov (United States)

    Kim, Kiho; Vasu, Dhananjayan; Im, Honggu; Hong, Sungwoo

    2016-07-18

    A straightforward synthetic strategy for generating useful anthracene derivatives was developed involving palladium(II)-catalyzed tandem transformation with carboxylic acids as traceless directing groups. Carboxyl-directed C-H alkenylation, carboxyl-directed secondary C-H activation and rollover, intramolecular C-C bond formation, and decarboxylative aromatization are proposed as the key steps in the tandem reaction pathway. This novel synthetic route utilizes a broad range of substrates and provides a convenient synthetic tool that allows access to acenes. PMID:27244536

  4. Aggregate Formed by a Cationic Fluorescence Probe

    Institute of Scientific and Technical Information of China (English)

    TIAN, Juan; SANG, Da-Yong; JI, Guo-Zhen

    2007-01-01

    The aggregation behavior of a cationic fluorescence probe 10-(4,7,10,13,16-pentaoxa-1-azacyclooctadecyl-methyl)anthracen-9-ylmethyl dodecanoate (1) was observed and studied by a fluorescence methodology in acidic and neutral conditions. By using the Py scale, differences between simple aggregates and micelles have been discussed. The stability of simple aggregates was discussed in terms of hydrophobic interaction and electrostatic repulsion. The absence of excimer emission of the anthrancene moiety of probe 1 in neutral condition was attributed to the photoinduced electron transfer mechanism instead of photodimerization.

  5. Modulating unimolecular charge transfer by exciting bridge vibrations.

    Science.gov (United States)

    Lin, Zhiwei; Lawrence, Candace M; Xiao, Dequan; Kireev, Victor V; Skourtis, Spiros S; Sessler, Jonathan L; Beratan, David N; Rubtsov, Igor V

    2009-12-23

    Ultrafast UV-vibrational spectroscopy was used to investigate how vibrational excitation of the bridge changes photoinduced electron transfer between donor (dimethylaniline) and acceptor (anthracene) moieties bridged by a guanosine-cytidine base pair (GC). The charge-separated (CS) state yield is found to be lowered by high-frequency bridge mode excitation. The effect is linked to a dynamic modulation of the donor-acceptor coupling interaction by weakening of H-bonding and/or by disruption of the bridging base-pair planarity.

  6. SILICON-CONTAINING POLY(p-ARYLENE VINYLENE)S: SYNTHESIS AND PHOTOPHYSICS

    Institute of Scientific and Technical Information of China (English)

    Shu-hong Li; Lei Fang; Rui Wang; Cai-hong Xu

    2012-01-01

    A series of new silicon-containing poly(p-arylene vinylene)s (PAVs) with anthracene units in the main chain were synthesized by hydrosilylation reaction.The introduction of organosilicon units improved the solubility of the polymers,and the π-π conjugation of polymeric chains was interrupted.These polymers behaved as blue-green light emitters with their fluorescence maximum at 447-499 nm and quantum yields in the range of 0.28-0.30 in solution.

  7. Effects of maternal exposure to cow´s milk high or low in isoflavones on carcinogen-induced mammary tumorigenesis among rat offspring

    DEFF Research Database (Denmark)

    Nielsen, Tina Skau; Purup, Stig; Warri, A;

    2011-01-01

    in female rat offspring. Pregnant Sprague-Dawley rats were given HIM, LIM or tap water (control) from gestational day (GD) 11 until birth; hereafter all rats received tap water. Mammary tumorigenesis was induced by administrating 7,12-dimethylbenz[a]anthracene (DMBA) on postnatal day (PND) 50....... No differences in maternal serum estradiol (P = 0.19) and IGF-1 levels (P = 0.15) at GD 19 or birth weight among the milk and water groups were seen, but estradiol, and IGF-1 levels and birth weight were numerically higher in the LIM than in the HIM group. Puberty onset occurred earlier in the LIM offspring than...

  8. Wetland treatment of oil and gas well wastewaters. Quarterly technical report, May 25, 1992---August 24, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Kadlec, R.H.; Srinivasan, K.R.

    1995-11-01

    The purpose of this study is to extend the knowledge base for wetland treatment to include processes and substances of particular importance to small, on-site systems receiving oil and gas well waste water. Collection of data on the sorption of heavy metals and the degradation of toxic organics is one of the key tasks. The toxic organics phenolics and anthracene, and chromium and copper have been selected as target adsorbates. An information search was performed on oil refinery waste treatment wetland systems.

  9. Synthesis and In-vitro Antibacterial Activities of Acetylanthracene and Acetylphenanthrene Derivatives of Some Fluoroquinolones

    Science.gov (United States)

    Shamsa, Fazel; Foroumadi, Alireza; Shamsa, Hashim; Samadi, Nasrin; Faramarzi, Mohammad Ali; Shafiee, Abbas

    2011-01-01

    Novel analogues of N-piperazinyl fluoroquinolones were prepared and evaluated against a panel of Gram-positive and Gram-negative bacteria, to study the effect of introducing bulky anthracene and phenanthrene moieties on the antibacterial effects of norfloxacin, ciprofloxacin and gatifloxacin. Although most of the novel synthesized compounds had lower antibacterial effects, some derivatives showed better activity in comparison with mother drugs based on molar concentration; for example, the 3-acetyl phenanthrene analogue of norfloxacin was more effective than E. coli and K. pneumonia. PMID:24250347

  10. Supercritical Fluid Reactions for Coal Processing

    Energy Technology Data Exchange (ETDEWEB)

    Charles A. Eckert

    1997-11-01

    Exciting opportunities exist for the application of supercritical fluid (SCF) reactions for the pre-treatment of coal. Utilizing reactants which resemble the organic nitrogen containing components of coal, we developed a method to tailor chemical reactions in supercritical fluid solvents for the specific application of coal denitrogenation. The tautomeric equilibrium of a Schiff base was chosen as one model system and was investigated in supercritical ethane and cosolvent modified supercritical ethane. The Diels-Alder reaction of anthracene and 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) was selected as a second model system, and it was investigated in supercritical carbon dioxide.

  11. Thermally-generated reactive intermediates: Trapping of the parent ferrocene-based o-quinodimethane and reactions of diradicals generated by hydrogen-atom transfers

    International Nuclear Information System (INIS)

    Ferrocenocyclobutene is prepared by flash vacuum pyrolysis (FVP) of the N-amino-2-phenylaziridine hydrazone of 2-methylferrocenealdehyde. In the second section of this dissertation, a series of hydrocarbon rearrangements were observed. FVP of o-allyltoluene at 0.1 Torr (700--900 C) gives 2-methylindan and indene, accompanied by o-propenyltoluene. FVP of 2-methyl-2'-vinylbiphenyl gives 9-methyl-9,10-dihydrophenanthrene, which fits the proposed mechanism. However, FVP of 2-(o-methylbenzyl)styrene gives mainly anthracene and 1-methylanthracene. This cyclization reaction was also successful with o-allylphenol and o-(2-methylallyl)phenol

  12. DAR Assisted Layer-by-Layer Assembly of Aromatic Compounds

    Institute of Scientific and Technical Information of China (English)

    姜思光; 陈晓东; 张莉; 刘鸣华

    2003-01-01

    A facile DAR (diphenylamine-4-diazonium-formaldehyde resin)assisted layer-by-layer (LbL) assembly of uitrathin organic film of aromatic compounds has been investigated. The muitilayer of pyrene or anthracene was fabricated through simple dipping of the glass slide into the mixed solution of DAR with the target compounds. In this method, DAR acted as an assistant compound to help the assembling of the aromatic compounds. Such a convenient deposition method not only reserves the advantages of the traditional LbL technique but also simplifies the technique and extends the effectiveness of LbL technique to small molecules without any charge.

  13. Charged Frenkel biexcitons in organic molecular crystals

    CERN Document Server

    Agranovich, V M; Kamchatnov, A M

    2001-01-01

    It is known that the energy of the lowest electronic transition in neutral molecules of anthracene, tetracene and other polyacenes is blue shifted in comparison with the corresponding transition energy in mono-valent molecular ions. This effect in molecular crystal may be responsible for the attraction between molecular (Frenkel) exciton and charge carrier. Due to this attraction the bound state of Frenkel exciton and free charge (charged Frenkel exciton) may be formed. The same mechanism can be responsible for formation of charged biexcitons (bound state of two Frenkel excitons and a charge carrier). Calculations are performed for molecular crystals like tetracene by means of one-dimensional lattice model

  14. The Effects of the KCNQ Openers Retigabine and Flupirtine on Myotonia in Mammalian Skeletal Muscle Induced by a Chloride Channel Blocker

    OpenAIRE

    Min-Jon Lin; George Hsiao; Ching-Chyuan Su; Wen-Shan Zei; Tzu-Rong Su

    2012-01-01

    The purpose of this study was to investigate the effect of KCNQ (potassium channel, voltage-gated, KQT-like subfamily) openers in preventing myotonia caused by anthracene-9-carboxylic acid (9-AC, a chloride channel blocker). An animal model of myotonia can be elicited in murine skeletal muscle by 9-AC treatment. KCNQ openers, such as retigabine and flupirtine, can inhibit the increased twitch amplitude (0.1 Hz stimulation) and reduce the tetanic fade (20 Hz stimulations) observed in the prese...

  15. Influence of the supramolecular order on the electrical properties of 1D coordination polymers based materials

    Science.gov (United States)

    Musumeci, Chiara; Osella, Silvio; Ferlauto, Laura; Niedzialek, Dorota; Grisanti, Luca; Bonacchi, Sara; Jouaiti, Abdelaziz; Milita, Silvia; Ciesielski, Artur; Beljonne, David; Hosseini, Mir Wais; Samorì, Paolo

    2016-01-01

    The generation, under self-assembly conditions, of coordination polymers on surface based combinations of a terpyridine-antracene-pyridine based tecton and Co(ii) or Pd(ii) cations is primarily governed by the coordination geometry of the metal center (octahedral and square planar respectively). While the octahedral Co(ii) based polymer self-assembles in insulating films exhibiting randomly oriented crystalline domains, the planarity of Pd(ii) based polymers leads to the formation of conductive π-π stacked fibrillar structures exhibiting anisotropically oriented domains. In the latter case, the favorable Pd-Pd and anthracene-anthracene wavefunction overlaps along the fiber direction are responsible for the large electronic couplings between adjacent chains, whereas small electronic couplings are instead found along individual polymer chains. These results provide important guidelines for the design of conductive metal coordination polymers, highlighting the fundamental role of both intra- as well as inter-chain interactions, thus opening up new perspectives towards their application in functional devices.The generation, under self-assembly conditions, of coordination polymers on surface based combinations of a terpyridine-antracene-pyridine based tecton and Co(ii) or Pd(ii) cations is primarily governed by the coordination geometry of the metal center (octahedral and square planar respectively). While the octahedral Co(ii) based polymer self-assembles in insulating films exhibiting randomly oriented crystalline domains, the planarity of Pd(ii) based polymers leads to the formation of conductive π-π stacked fibrillar structures exhibiting anisotropically oriented domains. In the latter case, the favorable Pd-Pd and anthracene-anthracene wavefunction overlaps along the fiber direction are responsible for the large electronic couplings between adjacent chains, whereas small electronic couplings are instead found along individual polymer chains. These results

  16. Temperature Effects on Retention and Separation of PAHs in Reversed-Phase Liquid Chromatography Using Columns Packed with Fully Porous and Core-Shell Particles

    OpenAIRE

    Christophe Waterlot; Anaïs Goulas

    2016-01-01

    Effects of temperature on the reversed-phase chromatographic behavior of PAHs were investigated on three columns. The first was the recent C18 column (250 mm × 4.6 mm) packed with 5 µm core-shell particles while the others were more conventional C18 columns (250 mm × 4.6 mm) packed with fully porous particles. Among the 16 PAHs studied, special attention has been paid to two pairs of PAHs, fluorene/acenaphthene and chrysene/benzo[a]anthracene, which often present coeluting problems. Due to th...

  17. 40 CFR 372.65 - Chemicals and chemical categories to which this part applies.

    Science.gov (United States)

    2010-07-01

    ... hydrochloride 134-29-2 1/1/87 Anthracene 120-12-7 1/1/87 Antimony 7440-36-0 1/1/87 Arsenic 7440-38-2 1/1/87... Bromotrifluoromethane (Halon 1301) 75-63-8 7/8/90 Bromoxynil (3,5-Dibromo-4-hydroxybenzonitrile) 1689-84-5 1/1/95... 63-25-2 1/1/87 Carbofuran 1563-66-2 1/1/95 Carbon disulfide 75-15-0 1/1/87 Carbon tetrachloride...

  18. Carcinogen inducibility in vivo and down-regulation of DMBT1 during breast carcinogenesis

    DEFF Research Database (Denmark)

    Mollenhauer, Jan; Helmke, Burkhard; Medina, Daniel;

    2004-01-01

    unambiguous inactivating DMBT1 mutations in breast cancer. Expression analyses in the human and mouse mammary glands pointed to the necessity of DMBT1 induction. While age-dependent and hormonal effects could be ruled out, 9 of 10 mice showed induction of Dmbt1 expression after administration...... of the carcinogen 7,12-dimethybenz(alpha)anthracene prior to the onset of tumorigenesis or other histopathological changes. DMBT1 displayed significant up-regulation in human tumor-flanking tissues compared to in normal breast tissues (P ... secretion to secretion to the extracellular matrix and a significant down-regulation compared to that in matched normal flanking tissues (P

  19. Laser-induced fluorescence studies of polycyclic aromatic hydrocarbons (PAH) vapors at high temperatures.

    Science.gov (United States)

    Chi, Z; Cullum, B M; Stokes, D L; Mobley, J; Miller, G H; Hajaligol, M R; Vo-Dinh, T

    2001-06-01

    In this work, we present the fluorescence spectra of anthracene and pyrene vapors at different elevated temperatures (from 150 to 650 degrees C) excited with the 337 nm line of a nitrogen laser. We describe the high temperature effects on the resulting spectral properties including spectral intensity, spectral bandwidth and spectral shift. We found that the PAH fluorescence spectral bandwidths become very broad as the temperature increases. The broadening is mainly due to thermal vibrational sequence congestion. We also have found that the fluorescence intensity of pyrene vapor increases with increasing temperature, which results from the increase of the pyrene vapor absorption cross section at 337 nm. PMID:11446693

  20. Mechanochemical Reactions of Fullerenes under High-Speed Vibration Milling

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ting-Hu; LI Yu-Jin; PENG Ru-Fang; LU Ping; CHEN Zhong-Xiu; WANG Guan-Wu

    2003-01-01

    @@ Since a novel technique called "high-speed vibration milling" (HSVM) was first applied to the Reformatskytype reaction of C60 in 1996, [1] this technique has been applied to various kinds of fullerene functionalizations including the preparation of C120. [2] Most recent reactions of fullerenes under HSVM conditions will be discussed: (1)reaction of C60/C70 with N-alkylglycines and aldehydes (Scheme 1); (2) reaction of C60 with active methylene compounds in the presence of bases (Scheme 2); (3) reaction of C6o with diazo compounds (Scheme 3); (4) reaction of C6o with anthracene derivatives (Scheme 4).

  1. Chemoprevention of DMBA-induced mammary carcinogenesis in rats by low-dose EPA and DHA.

    OpenAIRE

    Noguchi, M.; Minami, M; Yagasaki, R.; Kinoshita, K; Earashi, M.; Kitagawa, H; Taniya, T.; Miyazaki, I.

    1997-01-01

    We investigated the effects of low-dose eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the incidence and growth of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinoma in rats fed a high-fat (HF) diet. We also examined the effects of these treatments on the fatty acid composition of tumour and serum. Tumour incidence was significantly decreased by the administration of low-dose EPA and DHA, whereas their inhibitory effects on tumour growth did not reach significance....

  2. A pilot study of the novel J-PET plastic scintillator with 2-(4-styrylphenyl)benzoxazole as a wavelength shifter

    CERN Document Server

    Wieczorek, A; Niedźwiecki, Sz; Bednarski, T; Białas, P; Czerwiński, E; Danel, A; Gajos, A; Gruntowski, A; Kamińska, D; Kapłon, Ł; Kochanowski, A; Korcyl, G; Kowal, J; Kowalski, P; Kozik, T; Krzemień, W; Kubicz, E; Molenda, M; Pałka, M; Raczyński, L; Rudy, Z; Rundel, O; Salabura, P; Sharma, N G; Silarski, M; Słomski, A; Smyrski, J; Strzelecki, A; Uchacz, T; Wiślicki, W; Zieliński, M; Zoń, N

    2015-01-01

    For the first time a molecule of 2-(4-styrylphenyl)benzoxazole containing benzoxazole and stilbene groups is applied as a scintillator dopant acting as a wavelength shifter. In this article a light yield of the plastic scintillator, prepared from styrene doped with 2 wt% of 2,5-diphenylbenzoxazole and 0.03 wt% of 2-(4-styrylphenyl)benzoxazole, is determined to be as large as 60% $\\pm$ 2% of the anthracene light output. There is a potential to improve this value in the future by the optimization of the additives concentrations.

  3. Interaction of MeV ions and VUV photons with polymers and high molecular hydrocarbons

    Science.gov (United States)

    Mahfouz, R. M.; Sauer, M.; Atwa, S. T.; Kaiser, R. I.; Roessler, K.

    1992-03-01

    Organic solids such as polymethylene, polyethylene, polyoxymethylene, aliphatic and cyclic paraffins, naphthalene, anthracene and kerogen were irradiated at 77 K with 10-20 MeV cyclotron ions (p, 3He) and up to 10 eV photons. The products were analysed by quadrupole mass spectrometry (QMS). Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy and gas chromatography (GC). Besides radiolytic fragmentation, also synthesis of new and complex compounds was observed as a consequence of hot carbon chemistry. Vacuum ultraviolet (VUV) irradiation proved to be less effective in the buildup of new structures than MeV ions, due to its lower linear energy transfer.

  4. Synthesis of Polymer-bound Sensitizers and their Applications in the Preparation of Previtamin D3 from Tachysterol

    Institute of Scientific and Technical Information of China (English)

    YOU,Chang-Jiang(游长江); XIE,Rong(谢蓉); GAO,Yun-Yan(高云燕); HAN,Yong-Bin(韩永滨); YANG,Guo-Qiang(杨国强); Ll,Yi(李嫕)

    2004-01-01

    Two kinds of polymer-bound photosensitizers were synthesized,in which anthracene acts as sensitizer moiety,polystyrene (PS) and poly(methyl methylacrylate) (PMMA) serve as solid phase supports,respectively.The photoisomerization of tachysterol to previtamin D3 was carried out with these polymer-bound photosensitizers in ethanol and toluene solutions.The experiment results demonstrate that these solid phase photosensitizers are efficient for the photoisomerization with good recycle property and can be simply separated from the reaction mixtures by filtration.

  5. Myeloperoxidase and crystalline bodies in the granules of DMBA-induced rat chloroma cells.

    Science.gov (United States)

    Ioachim, H L; Keller, S; Sabbath, M; Andersson, B; Dorsett, B; Essner, E

    1972-01-01

    Chloroma (chloroleukemia) was induced in a splenectomized rat by repeatedly administering dimethylbenz(a)anthracene (DMBA) and was serially transplanted thereafter. Composed of immature myeloid cells, the tumor imparted a green discoloration to the tissues that it infiltrated extensively. Chloroma cells fluoresced red in ultraviolet light, produced a characteristic curve in spectrophotometry, and contained large amounts of myeloperoxidase. They included numerous intracytoplasmic granules of both types A and B, which contained occasional crystalline bars. Permanent lines of chloroma cells were established in tissue culture. These cells, while maintaining their initial morphology, ceased producing myeloperoxidase and subsequently induced white tumors when they were isotransplanted.

  6. Synthesis of o-Carboxyarylacrylic Acids by Room Temperature Oxidative Cleavage of Hydroxynaphthalenes and Higher Aromatics with Oxone.

    Science.gov (United States)

    Parida, Keshaba Nanda; Moorthy, Jarugu Narasimha

    2015-08-21

    A simple procedure for the synthesis of a variety of o-carboxyarylacrylic acids has been developed with Oxone (2KHSO5·KHSO4·K2SO4); the oxidation reaction involves the stirring of methoxy/hydroxy-substituted naphthalenes, phenanthrenes, anthracenes, etc. with Oxone in an acetonitrile-water mixture (1:1, v/v) at rt. Mechanistically, the reaction proceeds via initial oxidation of naphthalene to o-quinone, which undergoes cleavage to the corresponding o-carboxyarylacrylic acid. The higher aromatics are found to yield carboxymethyl lactones derived from the initially formed o-carboxyarylacrylic acids.

  7. Pitch-asphalts - new binder for road construction

    Energy Technology Data Exchange (ETDEWEB)

    Stompel, Z.; Collin, G.; Szen, A.; Herion, G.

    1988-01-01

    Discusses chemical and physical properties of a mixture of pitches and asphalts produced by the Blachownia Chemical Plant. The mixture consists of coal tar pitches with 25.7% content of toluene-insoluble fractions, anthracene oil and Dex asphalt. The following properties were analyzed: density, softening and softening point, adhesion, viscosity, sedimentation after 14 days. Physical and chemical properties of the pitch-asphalt from Blachownia were compared to those of pitch-asphalt from Ruetgerswerke AG in the FRG. Pitch-asphalt properties were evaluated from the point of view of their use in road construction. 8 refs.

  8. Contamination of agricultural lands by polycyclic aromatic hydrocarbons (Tver region, Russia)

    Science.gov (United States)

    Zhidkin, Andrey; Koshovskii, Timur; Gennadiev, Alexander

    2016-04-01

    It is important to study sources and concentrations of polycyclic aromatic hydrocarbons (PAHs) in the agriculture soils within areas without intensive contaminations. Our studied object was soil and snow cover in the taiga zone (Tver region, Russia). A total of 52 surface (0-30 cm) and 31 subsurface (30-50 cm) soil samples, and 13 snow samples were collected in 35 soil pits, located in forest, crop and layland soils. Studied concentrations of the following 11 individual compounds: two-ring compounds (diphenyl and naphthalene homologues); three-ring compounds (fluorene, phenanthrene, anthracene); four-ring compounds (chrysene, pyrene, tetraphene); five-ring compounds (perylene, benzo[a]pyrene); and six-ring compounds (benzo[ghi]perylene). Analyses made by specrtofluorometry method at the temperature of liquid nitrogen. The total concentrations of all PAHs in soil samples ranged from 9 to 770 ng*g‑1 with a median of 96 ng*g‑1. The sum of high molecular weight PAHs was significantly lower than the sum of low molecular weight PAHs in the studied soils. The phenanthrene concentration was highest and ranged from 1.2 to 720 ng*g‑1 (medium 72 ng*g‑1). Compared PAHs reserves in snow cover (μg*m-2) with the reserves in topsoil layer (μg*m-2 in the upper 30 cm). Low molecular weight PAHs (fluorene, phenanthrene, diphenyl, naphthalene) reserves in snow was less than 20% from the reserves in the soil surface layer. High molecular weight PAHs (benzo[a]pyrene, chrysene, perylene, pyrene and tetraphene) reserves in snow was about 50-70% from the reserves in soil surface layer. High molecular weight PAHs (benzo[ghi]perylene and anthracene) reserves in snow was more than in topsoil. PAHs vertical distribution in soil profiles was statistically examined. The total concentration of all PAHs decreased with depth in all studied forest soils. In the arable soils was no significant trend in domination of PAHs total concentrations in the plowing and subsoil layers. The ratio of

  9. Dynamic control of the location of nanoparticles in hybrid co-assemblies

    Science.gov (United States)

    Su, Zhilong; Li, Xiaokang; Jiang, Xuesong; Lin, Shaoliang; Yin, Jie

    2015-03-01

    We herein demonstrated an approach to control the spatial distribution of components in hybrid microspheres. Hybrid core-shell structured microspheres (CSMs) prepared through co-assembly were used as starting materials, which are comprised of anthracene-ended hyperbranched poly(ether amine) (AN-hPEA) in the shell and crystallized anthracene containing polyhedral oligomer silsesquioxane (AN-POSS). Upon thermal annealing at a temperature higher than the melting point of AN-POSS, the diffusion of AN-POSS from the core to the shell of CSM leads to a transition of morphology from the core-shell structure to core-transition-shell to the more stable homogeneous morphology, which has been revealed by experimental results of TEM and DSC. The mechanism for the morphology transition of CSM induced by the diffusion of AN-POSS was disclosed by a dissipative particle dynamics (DPD) simulation. A mathematical model for the diffusion of POSS in the hybrid microsphere is established according to Fick's law of diffusion and can be used to quantify its distribution in CSM. Thus, the spatial distribution of POSS in the microsphere can be controlled dynamically by tuning the temperature and time of thermal annealing.We herein demonstrated an approach to control the spatial distribution of components in hybrid microspheres. Hybrid core-shell structured microspheres (CSMs) prepared through co-assembly were used as starting materials, which are comprised of anthracene-ended hyperbranched poly(ether amine) (AN-hPEA) in the shell and crystallized anthracene containing polyhedral oligomer silsesquioxane (AN-POSS). Upon thermal annealing at a temperature higher than the melting point of AN-POSS, the diffusion of AN-POSS from the core to the shell of CSM leads to a transition of morphology from the core-shell structure to core-transition-shell to the more stable homogeneous morphology, which has been revealed by experimental results of TEM and DSC. The mechanism for the morphology transition

  10. Toxicity and EROD-inducing potency of 24 polycyclic aromatic hydrocarbons (PAHs) in chick embryos

    Energy Technology Data Exchange (ETDEWEB)

    Brunstroem, B. (Uppsala Univ. (Sweden). Dept. of Zoophysiology); Broman, D. (Stockholm Univ. (Sweden). Dept. of Zoology); Naef, C. (Stockholm Univ. (Sweden). Dept. of Analytical Chemistry)

    1991-08-01

    The toxicities (embryolethality) of 24 polycyclic aromatic hydrocarbons (PAHs) were determined in chick embryos using a 72-h test. The substances, dissolved in peanut oil, were injected into the air sacs of eggs preincubated for 7 days. LD{sub 50} values were determined for the four most toxic of the 24 compounds. Benzo(k)fluoranthene was the most potent, with an LD{sub 50} of 14 {mu}g (56 nmol)/kg egg. Dibenz(a,h)anthracene, benz(a)lanthracene and benzol(b)naphtho(2,3-d)thiophene were a few times less toxic (LD{sub 50} = 39 {mu}g (140 nmol)/kg, 79 {mu}g (349 nmol)/kg and 82 {mu}g (350 nmol)/kg, respectively). The LD{sub 50} of benzo(k)fluoranthene was only about 5 times higher than that previously found for the most potent coplanar polychlorinated biphenyl (PCB), 3,3',4,4',5-pentachlorobiphenyl (LD{sub 50} = 3.1 {mu}g (9.4 nmol)/kg), in the same kind of test. The toxicities of 18 of the PAHs in this study have also been evaluated previously using a 2-week test in chick embryos. Dibenz(a,h)anthracene, which had not been studied earlier in the 2-week test, proved to be almost as toxic as previously found for benzo(k)fluoranthene in that test. Several of the PAHs studied induced EROD activity in chick embryos, and, in general, the most toxic PAHs were also the most potent inducers of EROD. The highest enzyme activities were found after treatment with indeno(1,2,3-c,d)pyrene (12 times the control value) and dibenz(a,h)anthracene (8 times the control value). However, due to the high toxicity of dibenz(a,h)anthracene, the dose used was 7 times lower than that of indeno(1,2,3-c,d)pyrene. Following injection of PAHs on day 7, the EROD activities on day 10 were considerably lower than those obtained after a corresponding treatment with coplanar PCBs in an earlier study. Of the PAHs studied, some exhibited very high embryotoxicity. The most toxic PAHs induced EROD activity, suggesting that their toxicity was at least partly mediated via binding to the Ah receptor

  11. POLYMER-SUPPORTED GRIGNARD REAGENT AND ITS USE IN THE FUNCTIONALIZATION OF POLYMER

    Institute of Scientific and Technical Information of China (English)

    WANG Mingtai; ZONG Huijuan

    1995-01-01

    Polymeric Grignard Reagent (PGR) based on the chloromethylated poly(ST-co-DVB) resin has been prepared by means of anthracene-magnesium complex in THF (Anth-Mg-THF),and polymer matrix with long polymethylene spacer was synthesized via the coupling reaction between PGR and α, ω-dibromoalkanes. Based on the studies of factors affecting the coupling, such as catalyst,reaction time,the length of spacer etc. ,this paper offers the optimal reaction conditions and three typical experiment procedures. The mechanism for the formation and coupling reaction of PGR are also discussed.

  12. Avaliação da eficiência de degradação de hidrocarbonetos aromáticos por bactérias provinientes de estação de tratamento de efluente de refinaria de petróleo

    Directory of Open Access Journals (Sweden)

    Fernanda R. Pinhati

    2014-01-01

    Full Text Available Three bacterial strains were isolated from the activated sludge system of petroleum refinery wastewater, identified by partial sequencing of 16S rDNA, and classified as Acinetobacter genomospecies 3, Bacillus pumilus, and Bacillus flexus. The degradation efficiency of aromatic hydrocarbons was evaluated by gas chromatography with a flame ionization detector. In a mineral medium containing anthracene and phenanthrene and the consortium of microorganisms, the removal efficiency was 96% and 99%, respectively, after 30 days. The good rate of hydrocarbon degradation proves the operational efficiency of the microbial consortium in treating effluents containing these compounds.

  13. Far infrared (terahertz) spectroscopy of a series of polycyclic aromatic hydrocarbons and application to structure interpretation of asphaltenes and related compounds

    Science.gov (United States)

    Cataldo, Franco; Angelini, Giancarlo; García-Hernández, D. A.; Manchado, Arturo

    2013-07-01

    A series of 33 different polycyclic aromatic hydrocarbons (PAHs) were studied by far infrared spectroscopy (terahertz spectroscopy) in the spectral range comprised between 600 and 50 cm-1. In addition to common PAHs like naphthalene, anthracene, phenanthrene, fluoranthene, picene, pyrene, benzo[α]pyrene, and perylene, also quite unusual PAHs were studied like tetracene, pentacene, acenaphtene, acenaphtylene, triphenylene, and decacyclene. A series of alkylated naphthalenes and anthracenes were studied as well as methypyrene. Partially or totally hydrogenated PAHs were also object of the present investigation, ranging from tetrahydronaphthalene (tetralin) to decahydronaphthalene (decalin), 9,10-dihydroanthracene, 9,10-dihydrophenanthrene, hexahydropyrene, and dodecahydrotriphenylene. Finally, the large and quite rare PAHs coronene, quaterrylene, hexabenzocoronene, and dicoronylene were studied by far infrared spectroscopy. The resulting reference spectra were used in the interpretation of the chemical structure of asphaltenes (as extracted from a heavy petroleum fraction and from bitumen), the chemical structures of other petroleum fractions known as DAE (distillate aromatic extract) and RAE (residual aromatic extract), and a possible interpretation of components of the chemical structure of anthracite coal. Asphaltenes, heavy petroleum fractions, and coal were proposed as model compounds for the interpretation of the emission spectra of certain proto-planetary nebulae (PPNe) with a good matching in the mid infrared between the band pattern of the PPNe emission spectra and the spectra of these oil fractions or coal. Although this study was finalized in an astrochemical context, it may find application also in the petroleum and coal chemistry.

  14. Simultaneous Determination of 13 Priority Polycyclic Aromatic Hydrocarbons in Tehran's Tap Water and Water for Injection Samples Using Dispersive Liquid-Liquid Micro Extraction Method and Gas Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Sadeghi, Ramezan; Kobarfard, Farzad; Yazdanpanah, Hassan; Eslamizad, Samira; Bayate, Mitra

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are classified as persistent and carcinogenic organic pollutants. PAHs contamination has been reported in water. Many of relevant regulatory bodies such as EU and EPA have regulated the limit levels for PAHs in drinking water. In this study, 13 priority polycyclic aromatic hydrocarbons (PAHs) were determined in tap water samples of Tehran and water for injection. Dispersive liquid-liquid microextraction procedure combined with gas chromatography-mass spectrometry was used for the extraction and determination of PAHs in the samples. Under the optimized conditions, the range of extraction recoveries and relative standard deviations (RSDs) of PAHs in water using internal standard (anthracene-d10) were in the range of 71-90% and 4-16%, respectively. Limit of detection for different PAHs were between 0.03 and 0.1 ngmL(-1). The concentration of PAHs in all tap water as well as water for injection samples were lower than the limit of quantification of PAHs. This is the first study addressing the occurrence of PAHs in water for injection samples in Iran using dispersive liquid-liquid micro extraction procedure combined with gas chromatography-mass spectrometry.

  15. Biodegradation of polycyclic aromatic hydrocarbons in sediments from the Daliao River watershed, China

    Institute of Scientific and Technical Information of China (English)

    QUAN Xiangchun; TANG Qian; HE Mengchang; YANG Zhifeng; LIN Chunye; GUO Wei

    2009-01-01

    The Daliao River, as an important water system in Northeast China, was reported to be heavily polluted by polycyclic aromatic hydrocarbons (PAHs). Aerobic biodegradations of four selected PAHs (naphthalene, phenanthrene, fluorene and anthracene) alone or in their mixture in fiver sediments from the Daliao River water systems were studied in microcosm systems. Effects of additional carbon source, inorganic nitrogen and phosphorus, temperature variation on PAHs degradation were also investigated. Results showed that the degradation of phenanthrene in water alone system was faster than that in water-sediment combined system. Degradation of phenanthrene in sediment was enhanced by adding yeast extract and ammonium, but retarded by adding sodium acetate and not significantly influenced by adding phosphate. Although PAHs could also be biodegraded in sediment under low temperature (5℃), much lower degradation rate was observed. Sediments from the three main streams of the Daliao River water system (the Hun River, the Taizi River and the Daliao River) demonstrated different degradation capacities and patterns to four PAHs. Average removal rates (15 or 19 d) of naphthalene, phenanthrene, fluorene and anthracene by sediment were in the range of 0.062-0.087, 0.005-0.066, 0.008-one. In multiple PAHs systems, the interactions between PAHs influenced each PAH biodegradation.

  16. Tunneling of electrons via rotor-stator molecular interfaces: Combined ab initio and model study

    Science.gov (United States)

    Petreska, Irina; Ohanesjan, Vladimir; Pejov, Ljupčo; Kocarev, Ljupčo

    2016-07-01

    Tunneling of electrons through rotor-stator anthracene aldehyde molecular interfaces is studied with a combined ab initio and model approach. Molecular electronic structure calculated from first principles is utilized to model different shapes of tunneling barriers. Together with a rectangular barrier, we also consider a sinusoidal shape that captures the effects of the molecular internal structure more realistically. Quasiclassical approach with the Simmons' formula for current density is implemented. Special attention is paid on conformational dependence of the tunneling current. Our results confirm that the presence of the side aldehyde group enhances the interesting electronic properties of the pure anthracene molecule, making it a bistable system with geometry dependent transport properties. We also investigate the transition voltage and we show that conformation-dependent field emission could be observed in these molecular interfaces at realistically low voltages. The present study accompanies our previous work where we investigated the coherent transport via strongly coupled delocalized orbital by application of Non-equilibrium Green's Function Formalism.

  17. Photo-assisted intersystem crossing: The predominant triplet formation mechanism in some isolated polycyclic aromatic molecules excited with pulsed lasers

    International Nuclear Information System (INIS)

    Naphthalene, anthracene, and phenanthrene are shown to have very long-lived triplet lifetimes when the isolated molecules are excited with nanosecond pulsed lasers resonant with the lowest singlet state. For naphthalene, triplet state populations are created only during the laser pulse, excluding the possibility of normal intersystem crossing at the one photon level, and all molecules have triplet lifetimes greater than hundreds of microseconds, similar to the behavior previously reported for phenylacetylene. Although containing 7-12 thousand cm-1 of vibrational energy, the triplet molecules have ionization thresholds appropriate to vibrationless T1 states. The laser power dependences (slopes of log-log power plots) of the excited singlet and triplet populations are about 0.7 for naphthalene and about 0.5 for anthracene. Kinetic modeling of the power dependences successfully reproduces the experimental results and suggests that the triplet formation mechanism involves an enhanced spin orbit coupling caused by sigma character in states at the 2-photon level. Symmetry Adapted Cluster-Configuration Interaction calculations produced excited state absorption spectra to provide guidance for estimating kinetic rates and the sigma character present in higher electronic states. It is concluded that higher excited state populations are significant when larger molecules are excited with pulsed lasers and need to be taken into account whenever discussing the molecular photodynamics

  18. Synthesis of new condensed coumarin derivatives

    Directory of Open Access Journals (Sweden)

    Dekić Stojadin V.

    2007-01-01

    Full Text Available Reactions of 4-chloro-2-oxo-2H-chromene-3-carbonitrile (1 with 4-methylpyridin- 2-ylamine (2 and 6-methoxy-benzothiazol-2-ylamine (3 in acetonitrile containing a catalytic amount of triethylamine gave the new coumarin derivatives 7-imino-10-methyl-7H- 5-oxa-7a,12-diaza-benzo[a]anthracen-6-one (4 and 7-imino-10-methoxy-7H-5-oxa-12- thia-7a,13-diaza-indeno[1,2-b]phenanthren-6-one (5 in 52 and 39% yields, respectively. The novel compounds were subjected to acid hydrolysis giving the corresponding oxoderivatives 10-methyl-5-oxa-7a,12-diaza-benzo[a]anthracene-6,7-dione (6 and 10- methoxy-5-oxa-12-thia-7a,13-diaza-indeno[1,2-b]phenanthrene-6,7-dione (7 in 64 and 58% yields, respectively. The structural assignments of the synthesized compounds were based on elemental analyses, IR and proton NMR spectra. .

  19. Mutagenicity and polycyclic aromatic hydrocarbon content of fumes from heated cooking oils produced in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Tai-An; Ko, Ying-Chin [Graduate Institute of Medicine, Kaohsiung Medical College, Kaohsiung (Taiwan, Province of China); Wu, Pei-Fen [Department of Industrial Safety and Hygiene, Tajen Junior College of Pharmacy, Ping-Tung (Taiwan, Province of China); Wang, Li-Fang [School of Chemistry, Kaohsiung Medical College, Kaohsiung (Taiwan, Province of China); Lee, Huei [Department of Biochemistry, Chung San Medical and Dental College, Taichung (Taiwan, Province of China); Lee, Chien-Hung [School of Public Health, Kaohsiung Medical College, Kaohsiung (Taiwan, Province of China)

    1997-11-28

    According to epidemiologic studies, exposure of women to fumes from cooking oils appears to be an important risk factor for lung cancer. Fume samples from three different commercial cooking oils frequently used in Taiwan were collected and analyzed for mutagenicity in the Salmonella/microsome assay. Polycyclic aromatic hydrocarbons were extracted from the samples and identified by HPLC chromatography. Extracts from three cooking oil fumes were found to be mutagenic in the presence of S9 mix. All samples contained dibenz(a,h)anthracene (DB(a,h)A) and benz(a)anthracene (B(a)A). Concentration of DB(a,h)A and B(a)A were 1.9 and 2.2 {mu}g/m{sup 3} in fumes from lard oil, 2.1 and 2.3 {mu}g/m{sup 3} in soybean oil, 1.8 and 1.3 {mu}g/m{sup 3} in peanut oil, respectively. Benzo(a)pyrene (B(a)P) was identified in fume samples of soybean and peanut oil, in concentrations of 19.6 and 18.3 {mu}g/m{sup 3}, in this order. These results provide experimental evidence and support the findings of epidemiologic observations, in which women exposed to the emitted fumes of cooking oils are at increased risk of contracting lung cancer

  20. New scintillating media based on liquid crystals for particle detectors

    CERN Document Server

    Barnik, M I; Vasilchenko, V G; Golovkin, S V; Medvedkov, A M; Soloviev, A S

    2000-01-01

    The study results of optical, photoluminiscent and scintillation properties of a liquid crystal 4-pentyl-4'-cyanobiphenyl are presented. The scintillation light output of this liquid crystal is about 35% of crystal anthracene, its main decay time constants are 4 and 14 ns, and the maximum of light emission spectrum is about 400 nm. The light output of a dissolution of green emitting light scintillation dopant R6 in the liquid crystal is about 120% of crystal anthracene. The light output of the frozen dissolution measured at -112 deg. C is about 2.5 times higher as observed at +20 deg. C. In the uniaxially oriented liquid crystal, the predominant intensity direction of emitted light is pointed perpendicular to the liquid crystal director and an appreciable part of the emitted light is elliptically polarized. The possibility to use scintillation properties of liquid crystals is considered both for the improvement of existing particle detector characteristics and for the creation of new gated particle detectors.

  1. Oxidation of polycyclic aromatic hydrocarbons using partially purified laccase from residual compost of agaricus bisporus

    Energy Technology Data Exchange (ETDEWEB)

    Mayolo-Deloisa, K. [Center for Biotechnology Research, Autonomous University of Morelos State, Cuernavaca, Morelos (Mexico); Center for Biotechnology-FEMSA, Monterrey Institute of Technology, Campus Monterrey, Monterrey (Mexico); Machin-Ramirez, C. [Center for Biotechnology Research, Autonomous University of Morelos State, Cuernavaca, Morelos (Mexico); Faculty of Chemical Sciences and Engineering, Autonomous University of Morelos State, Cuernavaca, Morelos (Mexico); Rito-Palomares, M. [Center for Biotechnology-FEMSA, Monterrey Institute of Technology, Campus Monterrey, Monterrey (Mexico); Trejo-Hernandez, M.R. [Center for Biotechnology Research, Autonomous University of Morelos State, Cuernavaca, Morelos (Mexico)

    2011-08-15

    Laccase partially purified from residual compost of Agaricus bisporus by an aqueous two-phase system (Lac ATPS) was used in degrading polycyclic aromatic hydrocarbons: fluorene (Flu), phenanthrene (Phe), anthracene (Ant), benzo[a]pyrene (BaP), and benzo[a]anthracene (BaA). The capacity of the enzyme to oxidize polyaromatic compounds was compared to that of the crude laccase extract (CE). After treatment of 72 h, Lac ATPS and CE were not capable of oxidizing Flu and Phe, while Ant, BaP, and BaA were oxidized, resulting in percentages of oxidation of 11.2 {+-} 1, 26 {+-} 2, and 11.7 {+-} 4 % with CE, respectively. When Lac ATPS was used, the following percentages of oxidation were obtained: 11.4 {+-} 3 % for Ant, 34 {+-} 0.1 % for BaP, and 13.6 {+-} 2 % for BaA. The results reported here demonstrate the potential application of Lac ATPS for the oxidation of polycyclic aromatic hydrocarbons. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Identification of products formed during the heterogeneous nitration and ozonation of polycyclic aromatic hydrocarbons

    Science.gov (United States)

    Cochran, Richard E.; Jeong, Haewoo; Haddadi, Shokouh; Fisseha Derseh, Rebeka; Gowan, Alexandra; Beránek, Josef; Kubátová, Alena

    2016-03-01

    The 3- and 4-ring polycyclic aromatic hydrocarbons (PAHs) are the most abundant of PAHs in air particulate matter (PM). Thus we have investigated heterogeneous oxidation of 3- and 4-ring PAHs in a small-scale flow reactor using quartz filter as a support. Four representative PAHs, anthracene, phenanthrene, pyrene, and fluoranthene, were exposed to either NO2, O3 or NO2+O3 (NO3/N2O5) with a goal to identify and attempt quantification of major product distribution. A combination of gas chromatography with mass spectrometry (GC-MS) with/without derivatization and liquid chromatography with high resolution MS (LC-HRMS) was used for identification. For the first time, a comprehensive characterization of a broad range of products enabled identifying ketone/diketone, aldehyde, hydroxyl, and carboxylic acid PAH derivatives. Exposure to NO3/N2O5 (formed by reacting NO2 with O3, a more powerful reactant than either O3 or NO2) produced additional compounds not observed with either oxidant alone. Multiple isomers of nitrofluoranthene and, for the first time, nitrophenanthrene were identified. In addition hydroxy-nitro-PAH derivatives were observed for the reaction of anthracene with NO3/N2O5. Monitoring of specific common ions such as those of 176 and 205 m/z attributed to carbonyl phenanthrene and deprotonated phenanthrene ions respectively was shown to be a useful tool for identification of multiple pyrene oxidation products.

  3. Analysis on Heavy Metal and PAHs Pollution in Soil of Liaoyang Abandoned Industrial Zone%辽阳工业遗弃区土壤重金属和多环芳烃污染状况分析

    Institute of Scientific and Technical Information of China (English)

    何丽莉

    2011-01-01

    对某工业遗弃区土壤中重金属和多环芳烃( PAHs)污染状况进行调查,采用Harkanson“潜在生态危害指数法”及多介质环境目标值评价法对土壤中重金属及多环芳烃( PAHs)进行生态评价.结果表明:该地区的土壤受重金属污染,以汞、铜、锌、镍为重,污染排序为汞>铜>锌>镍>砷>镉>铅>铬;多环芳烃(PArs)中污染主要以笨并芘和二苯并(a,h)蒽、苯并(a)蒽为主.%This paper investigates heavy metal and polycyclic aromatic hydrocarbons (PAHs) pollution condition in soil of an abandoned industrial zone. Using Harkanson "potential ecological harm index method" and many medium environment target evaluation method to evaluate the heavy metal and polycyclic aromatic hydrocarbons (PAHs) ecological condition. The results show that the region's soil is seriously polluted by heavy metal Hg,CuZn,Ni. The general level of heavy metal pollution is Hg>Cu>Zn>Ni>As>Cd>Pb>Cr; while in the polycyclic aromatic hydrocarbons(PAHs) pollution, benzopytene ,diphenyl and (a, h) anthracene, benzene and (a) anthracene are the main pollutants.

  4. Gas chromatography-mass spectrometric determination of polycyclic aromatic hydrocarbons in five species of fish from three sites in the Arabian Gulf.

    Science.gov (United States)

    Al-Saleh, Iman; Al-Doush, Inaam

    2002-06-01

    A gas chromatography-mass spectrmetroic (GC-MS) method was developed to measure six polycyclic aromatic hydrocarbons (PAHs) in 54 fish samples. Five fish species highly consumed by the local population (shrimps, Emperors, Rabbitfish, Doublebar Bream and Greasy Grouper) were selected from three different sites on the Gulf coast of Saudi Arabia where agricultural, municipal and petroleum industry activities take place. Variations in PAH levels among the three sites were not significant. Total concentrations of PAHs benzo(a)anthracene, chrysene, and benzo(b)fluoranthene ranged from non-detectable to 44.9 microg kg(-1). In this study, concentrations of benzo(a)anthracene, chrysene, benzo(b)fluoranthene and total PAHs greater than the acceptable tolerance limit (1 microg kg(-1)) were found in 68.5, 40.7, 51.9 and 83.3% of the fish samples, respectively. PAH contents in fish vary considerably with species; Doublebar bream contain the highest while shrimps contain the lowest. This pilot study clearly shows that the consumption of fish could be a source of exposure of the local population to PAHs. Since there is a consensus on the substantial contribution of PAHs to cancer in humans, it would be interesting to conduct further research in order to determine the magnitude of the problem along other coastal regions of Saudi Arabia.

  5. Multiple stress effects on marine planktonic organisms: Influence of temperature on the toxicity of polycyclic aromatic hydrocarbons to Tetraselmis chuii

    Science.gov (United States)

    Vieira, L. R.; Guilhermino, L.

    2012-08-01

    In the present context of global warming and increasing long-range transport of oil and goods by sea potentially resulting in oil spills, more knowledge on the toxicological interactions between temperature and oil components on marine organisms is urgently needed. Therefore, the effects of temperature increase on the toxicity of three polycyclic aromatic hydrocarbons (PAH; anthracene, phenanthrene and naphthalene) to the marine planktonic algae Tetraselmis chuii were investigated under laboratory conditions. T. chuii cultures were exposed for 96 h to different concentrations of each of the test substances at both 20 and 25 °C. Effect criterion was the inhibition of culture growth assessed at 24 h intervals. All the PAHs significantly reduced T. chuii growth after 96 h of exposure with 20% inhibition concentrations between 0.052 and 1.124 mg L- 1 at 20 °C, and between 0.048 and 0.831 mg L- 1 at 25 °C. At both temperatures, the ranking, in order of decreasing toxicity based on the 50% inhibition concentration, was phenanthrene > naphthalene > anthracene. The increase of temperature by 5 °C significantly increased the toxicity of all the PAHs tested. These findings highlight the importance of considering temperature variation in the ecological risk assessment of oil and other chemical spills in the marine environment, and the need of more research on the toxic effects of multiple stressors on marine organisms.

  6. Distribution and Source of Polycyclic Aromatic Hydrocarbons (PAHs) in Water Dissolved Phase, Suspended Particulate Matter and Sediment from Weihe River in Northwest China.

    Science.gov (United States)

    Chen, Yuyun; Jia, Rui; Yang, Shengke

    2015-11-01

    Weihe River is a typical river located in the arid and semi-arid regions of Northwest China. In this study, the distribution and sources of 16 polycyclic aromatic hydrocarbons (PAHs) in Weihe River were investigated. The concentrations of ∑PAHs ranged from 351 to 4427 ng/L with a mean value of 835.4 ng/L in water dissolved phase (WDP), from 3557 ng/L to 147,907 ng/L with a mean value of 20,780 ng /L in suspended particulate matter (SPM), and from 362 to 15,667 ng/g dry weight (dw) with a mean value of 2000 ng/g dw in sediment, respectively. The concentrations of PAHs in Weihe River were higher compared with other rivers in the world. In both WDP and sediment, the highest concentrations of ∑PAHs were observed in the middle reach, while the lowest concentrations of ∑PAHs were found in the lower reach. For SPM, however, the PAHs concentrations in the lower reach were highest and the PAHs concentrations in the upper reach were lowest. The ratios of anthracene/(anthracene + phenanthrene) and fluoranthene/ (fluoranthene + pyrene) reflected a pattern of both pyrolytic and petrogenic input of PAHs in Weihe River. The potential ecosystem risk assessment indicated that harmful biological impairments occur frequently in Weihe River. PMID:26561824

  7. Controlled composting of waste wood contaminated with PAH; Untersuchungen zur gesteuerten Rotte von mit polyzyklischen aromatischen Kohlenwasserstoffen (PAK) kontaminiertem Altholz

    Energy Technology Data Exchange (ETDEWEB)

    Ulbricht, H.

    2002-07-01

    The author investigated the potential and limits of microbial pollutant degradation in PAH-polluted waste wood by composting. The conditions in which autochthonic micro-organisms are able to decomposite the PAH contained in wood by solid phase fermentation were investigated. The focus was on phenanthrene, anthracene and pyrene, all of which are used as protective materials (disinfestants) for wood. The results were verified on contaminated waste wood, including an analytical investigations of decomposition of PAH of the EPA catalogue. Boundary conditions for achieving high rates of PAH decomposition were investigated. [German] Generelles Ziel der Arbeit war die Untersuchung der Moeglichkeiten und Grenzen des mikrobiellen Schadstoffabbaus in PAK-belastetem Altholz durch Kompostierung und die Pruefung auf Anwendbarkeit der Erkenntnisse in technischen Verfahren. In der vorliegenden Arbeit wurde untersucht, unter welchen Bedingungen die autochthonen Mikroorganismen in der Lage sind, an das Holz gebundene PAK durch Feststofffermentation abzubauen. Als Schwerpunkt wurde zunaechst der Abbau der im zum Holzschutz verwendetem Teeroel vorkommenden PAK Phenanthren, Anthracen und Pyren untersucht. Eine Verifizierung der Ergebnisse erfolgte mit real kontaminiertem Altholz, dabei wurde der Abbau der PAK der EPA-Liste analytisch verfolgt. Es sollten geeignete Randbedingungen gefunden werden, um im Festphasensystem hohe Abbauraten der PAK zu erreichen. (orig.)

  8. Extraction of polycyclic aromatic hydrocarbons with a magnetic sorbent composed of alginate, magnetite nanoparticles and multiwalled carbon nanotubes

    International Nuclear Information System (INIS)

    The article describes a magnetic composite sorbent for the extraction of traces of polycyclic aromatic hydrocarbons (PAHs) from water samples. The composite was prepared by caging Fe3O4 nanoparticles (NPs) and MWCNTs into calcium alginate beads. The large surface area of the MWCNTs and their π-interactions with the aromatic rings of PAHs obviously facilitate strong adsorption. The hydrophilicity of the calcium alginate cage, in turn, enhances the dispersibility of the sorbent in the water sample. Finally, the use of magnetic NPs facilitates a simple and fast separation of the sorbent. The composite sorbent was successfully applied to the extraction of PAHs from (spiked) water samples. PAHs were quantified by HPLC with fluorescence detection. Under optimized experimental conditions, the calibration plot is linear in the range of 5 to 50 μg∙L−1 for benzo[a]anthracene and benzo[a]pyrene, and 10 to 50 μg∙L−1 for benzo[b]fluoranthene. Other figures of merit include a limit of detection of 5 ng∙L−1 for benzo[a]anthracene and benzo(a)pyrene, and of 10 ng∙L−1 for benzo[b]fluoranthene, recoveries ranging from 92.0 to 97.7 %, and relative standard deviations of <5 %. The method has several attractive features including an easily prepared and eco-friendly sorbent, a convenient and fast extraction procedure, and a high extraction efficiency. (author)

  9. Enhanced solubilisation of six PAHs by three synthetic cyclodextrins for remediation applications: molecular modelling of the inclusion complexes.

    Directory of Open Access Journals (Sweden)

    Esmeralda Morillo

    Full Text Available Solubilisation of six polycyclic aromatic hydrocarbons (PAHs (acenaphthene, anthracene, fluoranthene, fluorene, phenanthrene and pyrene by three synthetic cyclodextrins (CDs (2-hydroxypropyl-β-CD, hydroxypropyl-γ-CD and randomly methylated-β-CD was investigated in order to select the CD which presents the greatest increase in solubility and better complexation parameters for its use in contaminated scenarios. The presence of the three cyclodextrins greatly enhanced the apparent water solubility of all the PAHs through the formation of inclusion complexes of 1:1 stoichiometry. Anthracene, fluoranthene, fluorene and phenanthrene clearly presented a higher solubility when β-CD derivatives were used, and especially the complexes with the randomly methylated-β-CD were favoured. On the contrary, pyrene presented its best solubility results when using 2-hydroxypropyl-γ-CD, but for acenaphthene the use of any of the three CDs gave the same results. Complementary to experimental phase-solubility studies, a more in-depth estimation of the inclusion process for the different complexes was carried out using molecular modelling in order to find a correlation between the degree of solubilisation and the fit of PAH molecules within the cavity of the different CDs and to know the predominant driving forces of the complexation.

  10. Effect of roasting conditions on the polycyclic aromatic hydrocarbon content in ground Arabica coffee and coffee brew.

    Science.gov (United States)

    Houessou, Justin Koffi; Maloug, Saber; Leveque, Anne-Sophie; Delteil, Corine; Heyd, Bertrand; Camel, Valérie

    2007-11-14

    Roasting is a critical process in coffee production as it enables the development of flavor and aroma. At the same time, roasting may lead to the formation of nondesirable compounds, such as polycyclic aromatic hydrocarbons (PAHs). In this study, Arabica green coffee beans from Cuba were roasted under controlled conditions to monitor PAH formation during the roasting process. Roasting was performed in a pilot spouted bed roaster, with the inlet air temperature varying from 180 to 260 degrees C, using both dark (20 min) and light (5 min) roasting conditions. Several PAHs were determined in both roasted coffee samples and green coffee samples. Also, coffee brews, obtained using an electric coffee maker, were analyzed for final estimation of PAH transfer coefficients to the infusion. Formation of phenanthrene, anthracene, and benzo[a]anthracene in coffee beans was observed at temperatures above 220 degrees C, whereas formation of pyrene and chrysene required 260 degrees C. Low levels of benzo[g,h,i]perylene were also noted for dark roasting under 260 degrees C, with simultaneous partial degradation of three-cycle PAHs, suggesting that transformation of low molecular PAHs to high molecular PAHs occurs as the roasting degree is increased. The PAH transfer to the infusion was quite moderate (<35%), with a slightly lower extractability for dark-roasted coffee as compared to light-roasted coffee. PMID:17941690

  11. Modeling the formation of some polycyclic aromatic hydrocarbons during the roasting of Arabica coffee samples.

    Science.gov (United States)

    Houessou, Justin Koffi; Goujot, Daniel; Heyd, Bertrand; Camel, Valerie

    2008-05-28

    Roasting is a critical process in coffee production, as it enables the development of flavor and aroma. At the same time, roasting may lead to the formation of nondesirable compounds, such as polycyclic aromatic hydrocarbons (PAHs). In this study, Arabica green coffee beans from Cuba were roasted under controlled conditions to monitor PAH formation during the roasting process. Roasting was performed in a pilot-spouted bed roaster, with the inlet air temperature varying from 180 to 260 degrees C, for roasting conditions ranging from 5 to 20 min. Several PAHs were determined in both roasted coffee samples and green coffee samples. Different models were tested, with more or less assumptions on the chemical phenomena, with a view to predict the system global behavior. Two kinds of models were used and compared: kinetic models (based on Arrhenius law) and statistical models (neural networks). The numbers of parameters to adjust differed for the tested models, varying from three to nine for the kinetic models and from five to 13 for the neural networks. Interesting results are presented, with satisfactory correlations between experimental and predicted concentrations for some PAHs, such as pyrene, benz[a]anthracene, chrysene, and anthracene. PMID:18433138

  12. Photoresponsive Cellulose Nanocrystals

    Directory of Open Access Journals (Sweden)

    Dimitris S Argyropoulos

    2011-07-01

    Full Text Available In this communication a method for the creation of fluorescent cellulose nanoparticles using click chemistry and subsequent photodimerization of the installed side‐ chains is demonstrated. In the first step, the primary hydroxyl groups on the surface of the CNCs were converted to carboxylic acids by using TEMPO‐mediated hypohalite oxidation. The alkyne groups, essential for the click reaction, were introduced into the surface of TEMPO‐ oxidized CNCs via carbodiimide‐mediated formation of an amide linkage between monomers carrying an amine functionality and carboxylic acid groups on the surface of the TEMPO‐oxidized CNCs. Finally, the reaction of surface‐modified TEMPO‐oxidized cellulose nanocrystals and azido‐bearing coumarin and anthracene monomers were carried out by means of a click chemistry, i.e., Copper(I‐catalyzed Azide‐Alkyne Cycloaddition (CuAAC to produce highly photo‐responsive and fluorescent cellulose nanoparticles. Most significantly, the installed coumarin and/or anthracene side‐chains were shown to undergo UV‐induced [2+2] and [4+4] cycloaddition reactions, bringing and locking the cellulose nanocrystals together. This effort paves the way towards creating, cellulosic photo responsive nano‐arrays with the potential of photo reversibility since these reactions are known to be reversible at varying wavelengths.

  13. Far infrared (terahertz) spectroscopy of a series of polycyclic aromatic hydrocarbons and application to structure interpretation of asphaltenes and related compounds.

    Science.gov (United States)

    Cataldo, Franco; Angelini, Giancarlo; García-Hernández, D Aníbal; Manchado, Arturo

    2013-07-01

    A series of 33 different polycyclic aromatic hydrocarbons (PAHs) were studied by far infrared spectroscopy (terahertz spectroscopy) in the spectral range comprised between 600 and 50 cm(-1). In addition to common PAHs like naphthalene, anthracene, phenanthrene, fluoranthene, picene, pyrene, benzo[α]pyrene, and perylene, also quite unusual PAHs were studied like tetracene, pentacene, acenaphtene, acenaphtylene, triphenylene, and decacyclene. A series of alkylated naphthalenes and anthracenes were studied as well as methypyrene. Partially or totally hydrogenated PAHs were also object of the present investigation, ranging from tetrahydronaphthalene (tetralin) to decahydronaphthalene (decalin), 9,10-dihydroanthracene, 9,10-dihydrophenanthrene, hexahydropyrene, and dodecahydrotriphenylene. Finally, the large and quite rare PAHs coronene, quaterrylene, hexabenzocoronene, and dicoronylene were studied by far infrared spectroscopy. The resulting reference spectra were used in the interpretation of the chemical structure of asphaltenes (as extracted from a heavy petroleum fraction and from bitumen), the chemical structures of other petroleum fractions known as DAE (distillate aromatic extract) and RAE (residual aromatic extract), and a possible interpretation of components of the chemical structure of anthracite coal. Asphaltenes, heavy petroleum fractions, and coal were proposed as model compounds for the interpretation of the emission spectra of certain proto-planetary nebulae (PPNe) with a good matching in the mid infrared between the band pattern of the PPNe emission spectra and the spectra of these oil fractions or coal. Although this study was finalized in an astrochemical context, it may find application also in the petroleum and coal chemistry.

  14. A Survey of 42 Semi-Volatile Organic Contaminants in Groundwater along the Grand Canal from Hangzhou to Beijing, East China

    Directory of Open Access Journals (Sweden)

    Xiaojie Li

    2015-12-01

    Full Text Available The status of organic pollution in groundwater in eastern China along the Grand Canal from Hangzhou to Beijing was evaluated. Forty-two semi-volatile organic contaminants were analyzed, including 16 polycyclic aromatic hydrocarbons (PAHs, seven polychlorinated biphenyls (PCBs, 12 organochlorine pesticides (OCPs and seven organophosphorus pesticides (OPPs. Among the detected contaminants, PAHs were the most widespread compounds. One PCB and six OCPs were detected in the groundwater samples, but none of the target OPPs was detected. The total concentration of the 16 PAHs ranged from 0.21 to 1006 ng/L, among which phenanthrene (271 ng/L and fluoranthene (233 ng/L were present at very high concentrations and naphthalene (32 positive detections in 50 samples and fluorene (28 detections in 50 samples were the most frequently detected. Benzo[a]pyrene equivalents indicated a high environmental risk related to PAHs in a few groundwater samples. To identify the possible sources of PAHs, three concentration ratios, low molecular weight PAHs/high molecular weight PAHs, anthracene/(anthracene + phenanthrene and fluoranthene/(fluoranthene + pyrene, were determined, that indicated that the PAHs mainly originated from mixed sources: pyrolytic and petrogenic sources with different ratios at different sites.

  15. Polycyclic aromatic hydrocarbons in Italian preserved food products in oil.

    Science.gov (United States)

    Sannino, Anna

    2016-06-01

    A method based on gas chromatography/ tandem mass spectrometry was used to assess levels of 16 EU priority polycyclic aromatic hydrocarbons (PAHs) in 48 preserved food products in oil including foods such as vegetables in oil, fish in oil and oil-based sauces obtained from the Italian market. The benzo[a]pyrene concentrations ranged from <0.04 to 0.40 µg kg(-1), and 72.9% of the samples showed detectable levels of this compound. The highest contamination level was observed for chrysene with three additional PAHs (benzo[a]anthracene, benzo[b]fluoranthene and benzo[c]fluorene) giving mean values higher than the mean value for benzo[a]pyrene. Chrysene was detected in all the samples at concentrations ranging from 0.07 to 1.80 µg kg(-1) (median 0.31 µg kg(-1)). The contamination expressed as PAH4 (sum of benzo(a)pyrene, chrysene, benzo(a)anthracene and benzo(b)fluoranthene), for which the maximum tolerable limit has been set by Commission Regulation (EU) No. 835/2011, varied between 0.10 and 2.94 µg kg(-1). PMID:26886159

  16. Synthesis of Graphene Nanoribbons with Various Widths and Its Application to Thin-Film Transistor

    Science.gov (United States)

    Kim, Kyung Tae; Jo, Won Ho

    2013-03-01

    Although graphene itself is a zero-bandgap semimetal, graphene nanoribbon (GNR) with a width smaller than 10 nm exhibits semiconducting behavior that renders them suitable for active materials of electronic devices. Several methods have been reported to produce GNRs, such as lithography, unzipping of CNTs, mechanical exfoliation and CVD. However, the uncontrollable character of these methods or in some case the harsh conditions restrict severely the quality of the resulting graphenes and consequently limit their applications. In this study, we synthesized GNRs with various widths from the corresponding polymer precursors and investigated their TFT properties. For synthesis of GNRs, we first synthesized polymers with phenylene, naphthalene and anthracene units by the Suzuki coupling reaction between dibromine monomer and diboronic ester monomer. The polymers were then converted into the corresponding GNRs through intramolecular cyclodehydrogenation reaction. The cyclodehydrogenation were identified quantitatively by NMR analysis. All GNR-based TFTs showed ambipolar transport behavior. The anthracene-based GNR exhibits the best TFT performance among three GNRs due to longer conjugated length, larger width and stronger π-stacking as compared to phenylene- and naphthalene-based GNRs.

  17. A Molecular Precursor to Phosphaethyne and its Application in Synthesis of the Aromatic 1,2,3,4-Phosphatriazolate Anion

    Energy Technology Data Exchange (ETDEWEB)

    Transue, Wesley J.; Velian, Alexandra; Nava, Matthew; Martin-Drummel, Marie A.; Womack, Caroline C.; Jiang, Jun; Hou, Gao-Lei; Wang, Xue B.; McCarthy, Michael C.; Field, Robert W.; Cummins, Christopher C.

    2016-06-01

    Dibenzo-7-phosphanorbornadiene Ph3PC(H)PA (1, A = C14H10, anthracene) is reported as a molecular precursor to phosphaethyne (HC≡P), produced together with anthracene and triphenylphosphine. HCP generated by thermolysis of 1 has been characterized by molecular beam mass spectrometry (MBMS), laser-induced fluorescence (LIF), microwave spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. In toluene, fragmentation of 1 has been found to proceed with activation parameters of ΔH = 25.5 kcal/mol and ΔS = ₋2.43 e.u., and is accompanied by formation of an orange insoluble precipitate. Results from computational studies of the mechanism of HCP generation are in good agreement with experimental data. This high temperature method of HCP generation has pointed to new reaction chemistry with azide anion to produce the 1,2,3,4-phosphatriazolate anion, HCPN3- , for which structural data have been obtained in a single-crystal Xray diffraction study. Negative ion photoelectron spectroscopy has shown the adiabatic detachment energy for this anion to be 3.555(10) eV. The aromaticity of HCPN3- has been assessed using nucleus-independent chemical shift (NICS), quantum theory of atoms in molecules (QTAIM), and natural bond orbital (NBO) methods.

  18. Simultaneous Determination of 13 Priority Polycyclic Aromatic Hydrocarbons in Tehran's Tap Water and Water for Injection Samples Using Dispersive Liquid-Liquid Micro Extraction Method and Gas Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Sadeghi, Ramezan; Kobarfard, Farzad; Yazdanpanah, Hassan; Eslamizad, Samira; Bayate, Mitra

    2016-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are classified as persistent and carcinogenic organic pollutants. PAHs contamination has been reported in water. Many of relevant regulatory bodies such as EU and EPA have regulated the limit levels for PAHs in drinking water. In this study, 13 priority polycyclic aromatic hydrocarbons (PAHs) were determined in tap water samples of Tehran and water for injection. Dispersive liquid-liquid microextraction procedure combined with gas chromatography-mass spectrometry was used for the extraction and determination of PAHs in the samples. Under the optimized conditions, the range of extraction recoveries and relative standard deviations (RSDs) of PAHs in water using internal standard (anthracene-d10) were in the range of 71-90% and 4-16%, respectively. Limit of detection for different PAHs were between 0.03 and 0.1 ngmL(-1). The concentration of PAHs in all tap water as well as water for injection samples were lower than the limit of quantification of PAHs. This is the first study addressing the occurrence of PAHs in water for injection samples in Iran using dispersive liquid-liquid micro extraction procedure combined with gas chromatography-mass spectrometry. PMID:27642318

  19. Synthesis and photophysical properties of a single bond linked tetracene dimer

    Science.gov (United States)

    Sun, Tingting; Shen, Li; Liu, Heyuan; Sun, Xuan; Li, Xiyou

    2016-07-01

    A tetracene dimer linked directly by a single bond has been successfully prepared by using electron withdrawing groups to improve the stability. The molecular structure of this dimer is characterized by 1H NMR, MALDI-TOF mass spectroscopy, and elemental analysis. The minimized molecular structure and X-ray crystallography reveal that the tetracene subunits of this dimer adopt an orthogonal configuration. Its absorption spectrum differs significantly from that of its monomeric counterpart, suggesting the presence of strong interactions between the two tetracene subunits. The excited state of this dimer is delocalized on both two tetracene subunits, which is significantly different from that of orthogonal anthracene dimers, but similar with that observed for orthogonal pentacene dimer. Most of the excited states of this dimer decay by radioactive channels, which is different from the localized twisted charge transfer state (LTCT) channel of anthracene dimers and the singlet fission (SF) channel of pentacene dimers. The results of this research suggest that similar orthogonal configurations caused different propertied for acene dimers with different conjugation length.

  20. Polycyclic Aromatic Hydrocarbons Residues in Gentile Di Maiale, a Smoked Meat Product Typical of Some Mountain Areas in Latina Province (Central Italy)

    Science.gov (United States)

    Carrabs, Giuseppe; Mercogliano, Raffaelina; Carosielli, Leonardo; Vollano, Lucia; Anastasio, Aniello

    2014-01-01

    Gentile di maiale is a typical meat product prepared in some traditional plants of Latina Province (Central Italy). It is obtained from dehydration, salting, smoking and ripening of swine rectum. Aim of this study was to evaluate the influence of the traditional smoking process on polycyclic aromatic hydrocarbons (PAHs) content by means of high-performance liquid chromatographic/fluorescence detection. Polycyclic aromatic hydrocarbons detected in 8 samples of raw material (swine rectum) and samples of smoked gentile were: benzo[a]anthracene, chrisene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a] pyrene, benzo[a,h]anthracene. Their residues were detected in all samples of finished product. European Regulation 835/2011 established two levels of PAHs content in meat products. According to first levels, in force until September 2014, only 2 out of 8 samples exceeded legal limit. According to the subsequent, more restrictive, limits all samples would be non-compliant. An improvement and a standardisation of traditional smoking procedures are recommended.

  1. Polycyclic aromatic hydrocarbons residues in Gentile di maiale, a smoked meat product typical of some mountain areas in Latina province (Central Italy

    Directory of Open Access Journals (Sweden)

    Giuseppe Carrabs

    2014-05-01

    Full Text Available Gentile di maiale is a typical meat product prepared in some traditional plants of Latina Province (Central Italy. It is obtained from dehydration, salting, smoking and ripening of swine rectum. Aim of this study was to evaluate the influence of the traditional smoking process on polycyclic aromatic hydrocarbons (PAHs content by means of high-performance liquid chromatographic/fluorescence detection. Polycyclic aromatic hydrocarbons detected in 8 samples of raw material (swine rectum and samples of smoked gentile were: benzo[a]anthracene, chrisene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a] pyrene, benzo[a,h]anthracene. Their residues were detected in all samples of finished product. European Regulation 835/2011 established two levels of PAHs content in meat products. According to first levels, in force until September 2014, only 2 out of 8 samples exceeded legal limit. According to the subsequent, more restrictive, limits all samples would be non-compliant. An improvement and a standardisation of traditional smoking procedures are recommended.

  2. Effect of the alkyl chain length on the rotational dynamics of nonpolar and dipolar solutes in a series of N-alkyl-N-methylmorpholinium ionic liquids.

    Science.gov (United States)

    Khara, Dinesh Chandra; Kumar, Jaini Praveen; Mondal, Navendu; Samanta, Anunay

    2013-05-01

    Rotational dynamics of two dipolar solutes, 4-aminophthalimide (AP) and 6-propionyl-2-dimethylaminonaphthalene (PRODAN), and a nonpolar solute, anthracene, have been studied in N-alkyl-N-methylmorpholinium (alkyl = ethyl, butyl, hexyl, and octyl) bis(trifluoromethansulfonyl)imide (Tf2N) ionic liquids as a function of temperature and excitation wavelength to probe the microheterogeneous nature of these ionic liquids, which are recently reported to be more structured than the imidazolium ionic liquids (Khara and Samanta, J. Phys. Chem. B2012, 116, 13430-13438). Analysis of the measured rotational time constants of the solutes in terms of the Stokes-Einstein-Debye (SED) hydrodynamic theory reveals that with increase in the alkyl chain length attached to the cationic component of the ionic liquids, AP shows stick to superstick behavior, PRODAN rotation lies between stick and slip boundary conditions, whereas anthracene exhibits slip to sub slip behavior. The contrasting rotational dynamics of these probe molecules is a reflection of their location in distinct environments of the ionic liquids thus demonstrating the heterogeneity of these ionic liquids. The microheterogeneity of these media, in particular, those with the long alkyl chain, is further evidence from the excitation wavelength dependence study of the rotational diffusion of the dipolar probe molecules.

  3. Impacts of UV radiation and photomodification on the toxicity of PAHs to the higher plant Lemna gibba (duckweed)

    Energy Technology Data Exchange (ETDEWEB)

    Xiaodong Huang; Dixon, D.G.; Greenberg, B.M. (Univ., of Waterloo, Ontario (Canada). Dept. of Biology)

    1993-06-01

    The toxicity of polycyclic aromatic hydrocarbons (PAHs) can be enhanced by both biotic and abiotic processes. This is exemplified by light, which, by virtue of the extensive [pi]-orbital systems of PAHs, can be a major factor in PAH toxicity. Light activation of PAHs is known to occur via photosensitization reactions and potentially by photomodification of the chemicals to more toxic species. To examine the modes of PAH action in the light and determine if the photomodified compounds are hazardous, the authors investigated the photoinduced toxicity of anthracene, phenanthrene and benzo[a]pyrene to the aquatic higher plant Lemna gibba (a duckweed). Toxicity end points were inhibition of growth and extent of chlorosis. Light did indeed activated the phytotoxicity of PAHs, with UV radiation more effective than visible light. Dose-response curves based on chemical concentration and light intensity revealed the order of phytotoxic strength to be anthracene > phenanthrene > benzo[a]pyrene. To explore whether photomodified PAHs were contributing to toxicity, the chemicals were irradiated before toxicity testing. The rates of photomodification of the three PAHs were rapid, and the relative velocities were coincident with the order of toxic strength. Furthermore, the photomodified PAHs were more hazardous to Lemna than the intact compounds. Because interpretations of the potential impacts of PAHs in the environment are based mostly on measurements of the structurally intact chemicals, the severity of PAH hazards is possibly underestimated.

  4. Polycyclic aromatic hydrocarbons in sediments and mussels of the western Mediterranean Sea

    Energy Technology Data Exchange (ETDEWEB)

    Baumard, P.; Budzinski, H.; Garrigues, P. [Univ. Bordeaux I, Talence (France)

    1998-05-01

    The distribution of polycyclic aromatic hydrocarbons (PAHs) has been investigated in superficial sediments and mussels (Mytilus galloprovincialis) of the western Mediterranean sea. The analyses were performed by gas chromatography coupled to mass spectrometry (GC-MS). The PAH concentrations ranged from 1 to 20,500 ng/g in the sediments. Different molecular indices allowed differentiation between the different pollutant sources. On the French coast, PAHs originated mainly from incomplete combustion of organic matter (pyrolytic origin), whereas for some sites in Corsica and Sardinia an overimposition of petrogenic PAHs occurred. The mussel PAH concentrations ranged from 25 to 390 ng/g. The total and individual PAH bioaccumulation factors were calculated. The correlation between sediment and mussel PAH content was discussed in terms of bioavailability. It was possible to distinguish different absorption routes for the xenobiotics according to their physicochemical properties. Because the mussel distribution of phenanthrene and anthracene seems to be governed by their water solubility, these compounds were probably mainly absorbed as the water-dissolved form, whereas the heavier molecular weight PAHs (more than four aromatic rings), whose sediment and mussel concentrations are correlated with higher correlation coefficients than for phenanthrene and anthracene, were probably mainly absorbed as adsorbed on particles. Furthermore, a possible preferential biotransformation of benzo[a]pyrene over benzo[e]pyrene is discussed.

  5. Effect of frying and aluminium on the levels and migration of parent and oxygenated PAHs in a popular Chinese fried bread youtiao.

    Science.gov (United States)

    Li, Ge; Wu, Shimin; Zeng, Jianxiong; Wang, Lin; Yu, Wenjuan

    2016-10-15

    This study investigated the effects of frying conditions on the change, migration and correlation of polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs (oxy-PAHs) in youtiao, a typical Chinese fried bread. PAH migration was evaluated using an isotope tracer method. High concentrations of oxy-PAHs, especially 9-fluorenone (1.75μg/kg) and anthracene-9,10-dione (6.41μg/kg), were detected. The results revealed that 1) prolonged continuous frying decreased parent PAH and oxy-PAH concentrations, 2) frying temperature and aluminium content did not have significant effects on parent PAH concentrations, 3) PAH migration rates (2.02-18.48%) varied significantly based on the frying oil type, and 4) the sum of five oxy-PAH concentrations was significantly correlated with the sum of 16 parent PAH concentrations in soybean oil-fried youtiao. Three oxy-PAHs (9-fluorenone, anthracene-9,10-dione, and 9,10-dihydrobenzo[a]pyren-7(8h)-one) were significantly correlated with their respective parent PAHs. The results might be helpful for further study and evaluation on oxy-PAHs and PAHs in fried foods. PMID:27173543

  6. Distribution and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons in Soil from a Typical Contaminated Urban Coking Sites in Shenyang City.

    Science.gov (United States)

    Hou, Wei; Zhang, Le; Li, Yue; Zhang, Lihong; Li, Shuxian; Ji, Lan; Dan, Su

    2015-12-01

    This study evaluated the level of PAH pollution in typical contaminated coking sites in Shenyang. Sixty surface soil samples were collected from an area of 1.3 × 10(5) m(2) polluted by PAHs. The concentrations, sources and possible health risks of 16 PAHs in the area were analyzed. The average content of Σ16 PAHs was 6.1 × 10(3) mg/kg. In oral intake, benzo(a)pyrene (BaP) presented the largest exposure risk (hazard quotient HQ = 1.17 × 10(-5)), followed by dibenz(a,h)anthracene (DbA) (HQ = 1.14 × 10(-5)). The non-carcinogenic hazard indices and carcinogenic risks of the PAHs were arranged in the order of BaP > DbA > benzo(b)fluoranthene (BbF) > benz(a)anthracene (BaA) > indeno(1,2,3-cd)pyrene (InP) > benzo(k)fluoranthene (BkF) > chrysene (Chr). Bap and DbA were the principal pollution sources, followed by BbF, BaA, InP, BkF and Nap successively. Oral intake was the main route of PAH entry into the human body. PMID:26508427

  7. Effects of storage on sediment toxicity, bioaccumulation potential, and chemistry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tatem, H.E.; Brandon, D.L.; Lee, C.R.; Jarvis, A.S.; Rhett, R.G.

    1991-01-01

    Current guidance on storage of sediments for bioassay/bioaccumulation tests requires that samples be held at 4 C and used within 2 weeks of collection. The objective of this study was to determine the effects of sediment storage for 40 weeks on sediment toxicity, bioaccumulation potential, and chemical analyses. Toxicity and bioaccumulation tests were conducted five times during 40 weeks of storage. Chemical analyses were performed three times during this period. The data indicate that sediments can be held for longer than 2 to 4 weeks, in many cases, without significant effect on test results. However, results of the study also show that tests performed at different times can produce different results. This study showed that a sediment that was toxic to mysids remained toxic during 16 weeks of sediment storage. Two sediments that were toxic initially continued to show significant toxicity after 8 and 16 weeks of sediment storage. One sediment, not toxic initially or at 4 weeks, changed during storage, becoming significantly toxic compared to the Atlantic Ocean (Ref) sediment. The bioaccumulation results showed that certain sediment contaminants (lead, mercury, polychlorinated biphenyls, and some polycyclic aromatic hydrocarbons, PAHs), generally do not reveal a statistical change in bioaccumulation, relative to Ref animals, during 16 weeks of sediment storage. Other PAHs, including phenanthrene, anthracene, benzo (a) anthracene, and chrysene, did change in bioaccumulation potential during storage.

  8. Mechanistic investigation into the formation of polycyclic aromatic hydrocarbons from the pyrolysis of plant steroids

    Energy Technology Data Exchange (ETDEWEB)

    Britt, P.F.; Buchanan, A.C. III; Kidder, M.M.; Owens, C.; Ammann, J.R.; Skeen, J.T.; Luo, L. [Oak Ridge National Lab., Oak Ridge, TN (United States). Chemical and Analytical Sciences

    2001-10-09

    There have been many studies on the pyrolysis of biomass model compounds but most have not been performed under the high heating rate, short residence time conditions currently used in the thermochemical conversion of biomass. In this investigation, the pyrolysis of plant steroids is investigated by flash vacuum pyrolysis (FVP) and flow pyrolysis at residence times of 0.1-2.0 s and temperatures of 550-800{degree}C to determine if the native cyclic ring structure in the steroid leads to the formation of polycyclic aromatic hydrocarbons (PAHs) or whether PAHs are formed by pyrosynthesis. FVP of stigmasterol stigmasterol acetate, {beta}-sitosterol and stigmasta-3,5-diene at 700{degree}C showed that PAHs, such as acenaphthylene, phenanthrene, anthracene, pyrene, chrysene, benz(a)anthracene, and their monomethylated derivatives were formed in the absence of bimolecular reactions, and the yield of PAHs was dependent of the structure of the steroid. Similar products were found in the flow pyrolysis of stigmasterol, and the yields of PAHs were found to increase with increasing temperature and residence time. Thermochemical kinetic estimates were used to postulate pathways for the formation of the primary pyrolysis products. 66 refs., 9 figs., 7 tabs.

  9. Distribution and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons in Soil from a Typical Contaminated Urban Coking Sites in Shenyang City.

    Science.gov (United States)

    Hou, Wei; Zhang, Le; Li, Yue; Zhang, Lihong; Li, Shuxian; Ji, Lan; Dan, Su

    2015-12-01

    This study evaluated the level of PAH pollution in typical contaminated coking sites in Shenyang. Sixty surface soil samples were collected from an area of 1.3 × 10(5) m(2) polluted by PAHs. The concentrations, sources and possible health risks of 16 PAHs in the area were analyzed. The average content of Σ16 PAHs was 6.1 × 10(3) mg/kg. In oral intake, benzo(a)pyrene (BaP) presented the largest exposure risk (hazard quotient HQ = 1.17 × 10(-5)), followed by dibenz(a,h)anthracene (DbA) (HQ = 1.14 × 10(-5)). The non-carcinogenic hazard indices and carcinogenic risks of the PAHs were arranged in the order of BaP > DbA > benzo(b)fluoranthene (BbF) > benz(a)anthracene (BaA) > indeno(1,2,3-cd)pyrene (InP) > benzo(k)fluoranthene (BkF) > chrysene (Chr). Bap and DbA were the principal pollution sources, followed by BbF, BaA, InP, BkF and Nap successively. Oral intake was the main route of PAH entry into the human body.

  10. Detection and characterization of human serum antibodies to polycyclic aromatic hydrocarbon diol-epoxide DNA adducts

    Energy Technology Data Exchange (ETDEWEB)

    Newman, M.J.; Light, B.A.; Weston, A.; Tollurud, D.; Clark, J.L.; Mann, D.L.; Blackmon, J.P.; Harris, C.C.

    1988-07-01

    The presence of serum antibodies to the diol-epoxide DNA adducts of representative polycyclic aromatic hydrocarbons (PAH), chrysene, benz(a)anthracene and benzo(a)pyrene, was determined by ELISA using serum samples obtained from normal healthy individuals. Antibodies that reacted against PAH adducted-DNA, but not against PAH-adducted protein, were found in the serum of approximately 40% of the test individuals. Specificity analysis of the antibodies demonstrated that serological cross-reactions between the benzo(a)pyrene and the chrysene diol-epoxide adducts were present. Similar cross-reactivity between the benz(a)anthracene and the chrysene adducts was observed. Sera containing antibodies that were apparently specific for each of the three PAH-DNA adducts were also identified. The presence of antibodies to PAH-DNA adducts indicates both past exposure to these carcinogenic PAH and their metabolic activation to the DNA damaging metabolites. These antibodies may prove to be useful in both retrospective and prospective epidemiological studies of various diseases associated with PAH exposure.

  11. Triacontyl modified silica gel as a sorbent for the preconcentration of polycyclic aromatic hydrocarbons in aqueous samples prior to gas chromatographic-mass spectrometry determination

    Institute of Scientific and Technical Information of China (English)

    Yan

    2010-01-01

    Triacontyl modified silica gel as a sorbent coupled with gas chromatography-mass spectrometry (GC-MS) was developed to determine EPA prior 16 polycyclic aromatic hydrocarbons (PAHs) in water samples. Various parameters of solid-phase extraction such as organic modifier solvent, eluent, sample flow rate and volume were optimized. The developed method was found to yield a linear calibration curve in the concentration range of 0.05-8 μg/L with respect to naphthalene, acenaphthylene, acenaphthene and 0.01-8μg/L for dibenz[a,h]anthracene and 0.05-14 μg/L for fluorene, phenanthrene, anthracene and 0.01-14 μg/L for the rest of analytes. Furthermore, the good accuracy and repeatability of the method made sure the requirements for achieving reliable analysis of PAHs in the environmental water samples, and the recoveries of optimal method were in the range of 80-120% except to higher volatility PAHs. C30-bonded silica was proved to be an efficient sorbent for extraction of high molecular weight PAHs.

  12. A Molecular Precursor to Phosphaethyne and Its Application in Synthesis of the Aromatic 1,2,3,4-Phosphatriazolate Anion.

    Science.gov (United States)

    Transue, Wesley J; Velian, Alexandra; Nava, Matthew; Martin-Drumel, Marie-Aline; Womack, Caroline C; Jiang, Jun; Hou, Gao-Lei; Wang, Xue-Bin; McCarthy, Michael C; Field, Robert W; Cummins, Christopher C

    2016-06-01

    Dibenzo-7-phosphanorbornadiene Ph3PC(H)PA (1, A = C14H10, anthracene) is reported here as a molecular precursor to phosphaethyne (HC≡P), produced together with anthracene and triphenylphosphine. HCP generated by thermolysis of 1 has been observed by molecular beam mass spectrometry, laser-induced fluorescence, microwave spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. In toluene, fragmentation of 1 has been found to proceed with activation parameters of ΔH(⧧) = 25.5 kcal/mol and ΔS(⧧) = -2.43 eu and is accompanied by formation of an orange insoluble precipitate. Results from computational studies of the mechanism of HCP generation are in good agreement with experimental data. This high-temperature method of HCP generation has pointed to new reaction chemistry with azide anion to produce the 1,2,3,4-phosphatriazolate anion, HCPN3(-), for which structural data have been obtained in a single-crystal X-ray diffraction study. Negative-ion photoelectron spectroscopy has shown the adiabatic detachment energy for this anion to be 3.555(10) eV. The aromaticity of HCPN3(-) has been assessed using nucleus-independent chemical shift, quantum theory of atoms in molecules, and natural bond orbital methods. PMID:27171847

  13. The differences in transformation mechanism in natural and anthropogenic PAH in environmental system

    International Nuclear Information System (INIS)

    mg/L): Naphthalene-269,65; Acenaphthene+Fluorene -10,71; Phenanthrene-167,27; Anthracene-2,47; Fluoranthene-170,76; Benzo (a) anthracene-10,61; Chrysene-66,59; Benzo (b) fluoranthene-25,65; Benzo (k) fluoranthene-3,22; Benzo (a) pyrene-0,49; Dibenzo (a, h) anthracene-18,68; Indeno (1,2,3-cd) pyrene-6,13. For comparison were investigated near 50 samples of oil polluted soils selected from oilfield sites and was determined background level of PAH around of oilfields in radius of 700-1000 m

  14. Monitoring system for the study of autotrophic biofilms in bioremediation of polyaromatic compounds

    Science.gov (United States)

    Alarie, Jean P.; Bruttig, A.; Miller, Gordon H.; Hill, Walter; Vo-Dinh, Tuan

    1999-02-01

    carcinogens in laboratory animal assays. The parent homocyclic species, which contain only carbon and hydrogen, are the familiar polyaromatic hydrocarbon (PAH) compounds. In addition to the PAH compounds, there are thousands of substituted compounds that could have various substituent groups, such as alkyl, amino, chloro, cyano, hydroxy, oxy, or thio groups. In this study we investigate anthracene and pyrene as PAH model systems. A portable fiberoptic instrument capable of real-time measurements has been developed for field screening these PAHs in surface water and natural algae systems. Our preliminary studies investigated the detection limits of anthracene and pyrene and the adsorption properties of two algae using fluorescence monitoring. An exposure study of the algae to 5 ppb anthracene was performed to investigate the ability of the algae to adsorb PAHs.

  15. Biodegradation of petroleum-based oil wastes through composting.

    Science.gov (United States)

    Kirchmann, H; Ewnetu, W

    1998-01-01

    Composting of horse manure was used as a means of degradation of two oil wastes, oil sludge from petrol stations and petroleum residues from a refinery. Paraffin oil was chosen as a reference. Oil wastes decomposed to 78-93% during 4.5 months of composting. The degradation of the waste oils was higher than that of the reference paraffin oil and no difference was found between the two types of oil wastes concerning their decomposition. At the end of the experiment, most of the polyaromatic hydrocarbons had been degraded except pyrene, chrysene and dibenz(ah)anthracene. Gaseous losses of oil compounds through volatilisation from composts were found not to be significant.

  16. Hydrocarbons identified in extracts from estuarine water accommodated no. 2 fuel oil by gas chromatography-mass spectrometry

    Science.gov (United States)

    Lewis, B. W.; Walker, A. L.; Bieri, R. H.

    1974-01-01

    Results are presented on a computerized gas chromatograph-mass spectrometer analysis of methylene chloride and n-heptane extracts of a No. 2 fuel oil accommodated estuarine water sample. The analytical method is briefly described, and the limitations on the identifications are categorized. Some attempt was made to determine major and trace constituents in the water accommodate. Altogether 66 hydrocarbon compounds were identified specifically, and 75 compounds were partially identified. Seven compounds could be recognized as major constituents of the water accommodated oil and ten were present only as traces. The aromatic compounds found were alkyl benzenes, naphthalene, tetralin, indane, biphenyl, fluorene, anthracene, and some of their alkyl substituted isomers in the range of carbon numbers C7 to C15. Four n-alkanes, C10 to C13, were found along with four other assorted hydrocarbons.

  17. A brief history of the development of organic and polymeric photovoltaics

    DEFF Research Database (Denmark)

    Spanggaard, H.; Krebs, Frederik C

    2004-01-01

    In this paper an overview of the development of organic photovoltaics is given, with emphasis on polymer-based solar cells. The observation of photoconductivity in solid anthracene in the beginning of the 19th century marked the start of this field. The first real investigations of photovoltaic (PV......) devices came in the 1950s, where a number of organic dyes, particularly chlorophyll and related compounds, were studied. In the 1980s the first polymers (including poly(sulphur nitride) and polyacetylene) were investigated in PV cells. However, simple PV devices based on dyes or polymers yield limited...... power conversion efficiencies (PCE), typically well below 0.1%. A major breakthrough came in 1986 when Tang discovered that bringing a donor and an acceptor together in one cell could dramatically increase the PCE to 1%. This concept of heterojunction has since been widely exploited in a number of donor...

  18. High incidence of ultraviolet-B- or chemical-carcinogen-induced skin tumours in mice lacking the xeroderma pigmentosum group A gene

    International Nuclear Information System (INIS)

    Xeroderma pigmentosum (XP) is an autosomal recessive disorder characterized by a high frequency of skin cancer on sun-exposed areas, and neurological complications. XP has a defect in the early step(s) of nucleotide-excision repair (NER) and consists of eight different genetic complementation groups (groups A-G and a variant)1. We established XPA (group-A XP) gene-deficient mice by gene targeting of mouse embryonic stem (ES) cells. The XPA-deficient mice showed neither obvious physical abnormalities more pathological alterations, but were defective in NER and highly susceptible to ultraviolet-B- or 9,10-dimethyl-1,2-benz[a]anthracene-induced skin carcinogenesis. These findings provide in vivo evidence that the XPA protein protects mice from carcinogenesis initiated by ultraviolet or chemical carcinogen. The XPA-deficient mice may provide a good in vivo model to study the high incidence of carcinogenesis in group A XP patients. (Author)

  19. Radiation Hard & High Light Yield Scintillator Search for CMS Phase II Upgrade

    CERN Document Server

    Tiras, Emrah

    2015-01-01

    The CMS detector at the LHC requires a major upgrade to cope with the higher instantaneous luminosity and the elevated radiation levels. The active media of the forward backing hadron calorimeters is projected to be radiation-hard, high light yield scintillation materials or similar alternatives. In this context, we have studied various radiation-hard scintillating materials such as Polyethylene Terephthalate (PET), Polyethylene Naphthalate (PEN), High Efficiency Mirror (HEM) and quartz plates with various coatings. The quartz plates are pure Cerenkov radiators and their radiation hardness has been confirmed. In order to increase the light output, we considered organic and inorganic coating materials such as p-Terphenyl (pTp), Anthracene and Gallium-doped Zinc Oxide (ZnO:Ga) that are applied as thin layers on the surface of the quartz plates. Here, we present the results of the related test beam activities, laboratory measurements and recent developments.

  20. Radiation Hard and High Light Yield Scintillator Search for CMS Phase II Upgrade

    CERN Document Server

    Tiras, Emrah

    2015-01-01

    The CMS detector at the LHC requires a major upgrade to cope with the higher instantaneous luminosity and the elevated radiation levels. The active media of the forward backing hadron calorimeters is projected to be radiation-hard, high light yield scintillation materials or similar alternatives. In this context, we have studied various radiation-hard scintillating materials such as Polyethylene Terephthalate (PET), Polyethylene Naphthalate (PEN), High Efficiency Mirror (HEM) and quartz plates with various coatings. The quartz plates are pure Cerenkov radiators and their radiation hardness has been confirmed. In order to increase the light output, we considered organic and inorganic coating materials such as p-Terphenyl (pTp), Anthracene and Gallium-doped Zinc Oxide (ZnO Ga) that are applied as thin layers on the surface of the quartz plates. Here, we present the results of the related test beam activities, laboratory measurements and recent developments.