Journal articles: 'Aromatico'

1

Lanati, Donato, Dora Marchi, Giacomo Mazza, Desislava Baicheva, and Alberto La Rosa. "Profilo aromatico varietale delle uve Mavrud, Bouquet e Rubin." BIO Web of Conferences 9 (2017): 02035. http://dx.doi.org/10.1051/bioconf/20170902035.

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Tang, Jianhong, Jiarong Li, Lijun Zhang, Shuling Ma, Daxin Shi, Qi Zhang, Liupan Yang, Xiuzhen Wang, Xuan Liu, and Change Liu. "The Divergent Transformations of Aromatico-Aminonitrile with Carbonyl Compound." Journal of Heterocyclic Chemistry 49, no. 3 (May 2012): 533–42. http://dx.doi.org/10.1002/jhet.804.

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Naidu, Devendra, and Stephen W. Ragsdale. "Characterization of a Three-Component Vanillate O-Demethylase from Moorella thermoacetica." Journal of Bacteriology 183, no. 11 (June 1, 2001): 3276–81. http://dx.doi.org/10.1128/jb.183.11.3276-3281.2001.

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ABSTRACT The Moorella thermoacetica aromaticO-demethylase was characterized as an inducible three-component system with similarity to the methanogenic methanol, methylamine, and methanethiol methyltransferases and to theO-demethylase system from Acetobacterium dehalogenans. MtvB catalyzes methyl transfer from a phenylmethylether to the cobalt center of MtvC, a corrinoid protein. MtvA catalyzes transmethylation from MtvC to tetrahydrofolate, forming methyltetrahydrofolate. Cobalamin can substitute for MtvC.

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Machovina, Melodie M., Sam J. B. Mallinson, Brandon C. Knott, Alexander W. Meyers, Marc Garcia-Borràs, Lintao Bu, Japheth E. Gado, et al. "Enabling microbial syringol conversion through structure-guided protein engineering." Proceedings of the National Academy of Sciences 116, no. 28 (June 24, 2019): 13970–76. http://dx.doi.org/10.1073/pnas.1820001116.

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Microbial conversion of aromatic compounds is an emerging and promising strategy for valorization of the plant biopolymer lignin. A critical and often rate-limiting reaction in aromatic catabolism isO-aryl-demethylation of the abundant aromatic methoxy groups in lignin to form diols, which enables subsequent oxidative aromatic ring-opening. Recently, a cytochrome P450 system, GcoAB, was discovered to demethylate guaiacol (2-methoxyphenol), which can be produced from coniferyl alcohol-derived lignin, to form catechol. However, native GcoAB has minimal ability to demethylate syringol (2,6-dimethoxyphenol), the analogous compound that can be produced from sinapyl alcohol-derived lignin. Despite the abundance of sinapyl alcohol-based lignin in plants, no pathway for syringol catabolism has been reported to date. Here we used structure-guided protein engineering to enable microbial syringol utilization with GcoAB. Specifically, a phenylalanine residue (GcoA-F169) interferes with the binding of syringol in the active site, and on mutation to smaller amino acids, efficient syringolO-demethylation is achieved. Crystallography indicates that syringol adopts a productive binding pose in the variant, which molecular dynamics simulations trace to the elimination of steric clash between the highly flexible side chain of GcoA-F169 and the additional methoxy group of syringol. Finally, we demonstrate in vivo syringol turnover inPseudomonas putidaKT2440 with the GcoA-F169A variant. Taken together, our findings highlight the significant potential and plasticity of cytochrome P450 aromaticO-demethylases in the biological conversion of lignin-derived aromatic compounds.

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Yang, Junjuan, Daxin Shi, Mingxing Liu, Lijun Zhang, Qi Zhang, and Jiarong Li. "Structure of the Condensed Product of Aromatico-Aminonitrile with Carbonyl Compound and Its Mechanism." Chinese Journal of Organic Chemistry 34, no. 12 (2014): 2424. http://dx.doi.org/10.6023/cjoc201406007.

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Kancherla, Sindhu, Marianne Lorentzen, Victor Snieckus, and Kåre B. Jørgensen. "Directedortho-Metalation and Anionicortho-Fries Rearrangement of Polycyclic AromaticO-Carbamates: Regioselective Synthesis of Substituted Chrysenes." Journal of Organic Chemistry 83, no. 7 (March 15, 2018): 3590–98. http://dx.doi.org/10.1021/acs.joc.7b03210.

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7

Shuvaev, Sergey, Ivan S. Bushmarinov, Ilya Sinev, Artem O. Dmitrienko, Konstantin A. Lyssenko, Vladimir Baulin, Wolfgang Grünert, Aslan Yu Tsivadze, and Natalia Kuzmina. "Copper(II) Complexes with Aromatico-Phosphorylated Phenols - Synthesis, Crystal Structures, and X-ray Photoelectron Spectroscopy." European Journal of Inorganic Chemistry 2013, no. 27 (July 10, 2013): 4823–31. http://dx.doi.org/10.1002/ejic.201300540.

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Kudlich, Michael, Malcolm J. Hetheridge, Hans-Joachim Knackmuss, and Andreas Stolz. "Autoxidation Reactions of Different Aromatico-Aminohydroxynaphthalenes That Are Formed during the Anaerobic Reduction of Sulfonated Azo Dyes." Environmental Science & Technology 33, no. 6 (March 1999): 896–901. http://dx.doi.org/10.1021/es9808346.

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9

Zhao, Kai Yun, Dong Bei Yue, and Ting Yang. "Characterization of Aromatics at Working Surface of a Municipal Solid Waste Landfill." Applied Mechanics and Materials 768 (June 2015): 458–64. http://dx.doi.org/10.4028/www.scientific.net/amm.768.458.

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With the rapid urbanization and economic growth in China especially near 2 decades, the vast amount of municipal solid waste (MSW) were produced annually. Landfills are the predominant disposal sites for MSW in China, receiving more than 75% of the collected MSW every year. While the volume concentration is usually less than 1%, NMOCs are generally considered as the main source of the odorous problem at MSW landfills, because they include many compounds with very low odor thresholds. What’s more, aromatics is vital part of NMOCs for its toxic effect, which contains Benzene. The main objective of this study was to understand the comprehensive behavior of aromatics of landfill gas. In this work we present an integrated evaluation of working surface concentration distribution and emission rate of a municipal solid waste landfill. And in order to understand the transportation of aromatic, a new parameter was introduced to analyze this process. Thus, result shows, the fugitive emission of aromatics in the operating surface may need pay more attention. The highest average concentration for aromatics was found in autumn. Aromatic’s emission rate in winter was larger than autumn, the highest emission rate of aromatics toluene, 0.011g/m2/h. The B:T ratio in winter was significant higher that of other seasons.

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10

Lu, Zhengyu, Qin Zhu, Yuanting Cai, Zhixin Chen, Kaiyue Zhuo, Jun Zhu, Hong Zhang, and Haiping Xia. "Access to tetracyclic aromatics with bridgehead metals via metalla-click reactions." Science Advances 6, no. 3 (January 2020): eaay2535. http://dx.doi.org/10.1126/sciadv.aay2535.

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The never-ending pursuits for exploring aromatic molecular architectures result in the large libraries of aromatics with fascinating structures, which have greatly broadened the scope of aromaticity. Despite extensive efforts that have been paid to develop aromatic frameworks, the construction of polycyclic aromatics that share a bridgehead atom with more than three rings has never been accomplished. Here, an unprecedented family of aromatics, in which a metal center shared by 4 five-membered aromatic rings, has been achieved by using the metalla-click reactions with excellent yields and remarkable regioselectivity. The distinctive tetracyclic aromatics exhibit a broad absorption in the ultraviolet-visible near-infrared region and excellent thermal stability in air, enabling their potential applications in photoelectric materials and biomedicine. This study now makes it possible to incorporate four aromatic rings with one common sharing metal center by a straightforward strategy that would promote further development of previously unknown polycyclic complex motifs in aromatic chemistry.

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11

Konopski, Leszek, and Anna Kiełczewska. "Application of 2-Trichloromethylbenzimidazole in Analytical Chemistry: A Highly Selective Chromogenic Reagent for Thin-Layer Chromatography and Some Other Analytical Uses." Journal of Analytical Methods in Chemistry 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/650150.

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2-Trichloromethylbenzimidazole (TCMB) was used as a chromogenic reagent in organic or inorganic analysis, mainly in thin-layer chromatography (TLC). In reactions of TCMB with some heteroaromatic nitrogen containing compounds, such as azines, azoles and benzazoles, a formation of high colored products occurred. For azines, the chromogenic reaction was highly regioselective, since the both adjacentα-positionsversusthe nitrogen atom(s) must not be substituted. A TLC method of detection was developed. Thirty azines, azoles, and benzazoles were detected at the detection limit 10 ng to 1 μg. This method was also applied for detection of heteroaromatic pesticides, and the attempts to construct active and passive dosimeters for nicotine were made. In a prechromatographic reaction of aromatico-diamines with methyl trichloroacetimidate, TCMB or its derivatives were formedin situ. Followed by TLC and visualization in pyridine vapors, this procedure was applied for detection ofo-phenylenediamine derivatives. The reaction product of TCMB and pyridine (LI Complex) was identified and fully characterized. Two different reaction mechanisms: with electron deficient basic heteroaromatic compounds, like pyridine, and with more acidic compounds, for example, pyrrole, were discussed. In aqueous solutions, the LI Complex may be also used as a new indicator for complexometric, adsorption and acid-base titration of inorganic compounds.

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12

Ottersbach, Philipp A., Paul W. Elsinghorst, Hans-Georg Häcker, and Michael Gütschow. "Direct Formation of Ring-Fused 1,3-Thiazine-2,4-dithiones from Aromatico-Amino Carboxylic Acids: Observation of a Carbon Disulfide Mediated Thionation." Organic Letters 12, no. 16 (August 20, 2010): 3662–65. http://dx.doi.org/10.1021/ol101471g.

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13

Costa Pessoa, João, Susana Marcão, Isabel Correia, Gisela Gonçalves, Agnes Dörnyei, Tamás Kiss, Tamás Jakusch, et al. "Vanadium (IV and V) Complexes of Reduced Schiff Bases Derived from the Reaction of Aromatico-Hydroxyaldehydes and Diamines Containing Carboxyl Groups." European Journal of Inorganic Chemistry 2006, no. 18 (September 2006): 3595–606. http://dx.doi.org/10.1002/ejic.200600309.

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14

Linz, Alexandra M., Yanjun Ma, Samuel Scholz, Daniel R. Noguera, and Timothy J. Donohue. "iNovo479: Metabolic Modeling Provides a Roadmap to Optimize Bioproduct Yield from Deconstructed Lignin Aromatics by Novosphingobium aromaticivorans." Metabolites 12, no. 4 (April 18, 2022): 366. http://dx.doi.org/10.3390/metabo12040366.

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Lignin is an abundant renewable source of aromatics and precursors for the production of other organic chemicals. However, lignin is a heterogeneous polymer, so the mixture of aromatics released during its depolymerization can make its conversion to chemicals challenging. Microbes are a potential solution to this challenge, as some can catabolize multiple aromatic substrates into one product. Novosphingobium aromaticivorans has this ability, and its use as a bacterial chassis for lignin valorization could be improved by the ability to predict product yields based on thermodynamic and metabolic inputs. In this work, we built a genome-scale metabolic model of N. aromaticivorans, iNovo479, to guide the engineering of strains for aromatic conversion into products. iNovo479 predicted product yields from single or multiple aromatics, and the impact of combinations of aromatic and non-aromatic substrates on product yields. We show that enzyme reactions from other organisms can be added to iNovo479 to predict the feasibility and profitability of producing additional products by engineered strains. Thus, we conclude that iNovo479 can help guide the design of bacteria to convert lignin aromatics into valuable chemicals.

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15

Putrawan, I. Dewa Gede Arsa. "Aqueous liquid membrane process for recovery of BTX aromatics." Jurnal Teknik Kimia Indonesia 11, no. 1 (October 2, 2018): 1. http://dx.doi.org/10.5614/jtki.2012.11.1.1.

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An aqueous liquid membrane process has been developed for extracting BTX aromatics in catalytic reformate. The process mainly involved a multistage liquid-membrane permeator and two distillation towers. Continuous stirred vessels were utilized as contactors for permeation. Aqueous solution of saponin and light oil were used as liquid membrane and receiving phase, respectively. The equations of material balance, permeation, and constrain have been solved to study the effects of operating variables on the product yield and BTX purity. BTX purity up to 95% and yield of 90% could be achieved. The larger the values of solvent-to-feed ratio, stirring rate, number of permeation stages, permeator reflux ratio, or permeator volume, the greater the energy requirement. The energy supplied to the process is mainly utilized to recover solvent. Solvent-to-feed ratio was found to be the most influential variable on energy demand. The purity of BTX aromatics increases as the permeator reflux ratio and solvent-to-feed ratio increase or the stirring rate, number of permeation stages, and permeator volume decrease. The opposite trends are observed for the yield of BTX aromatics. The raffinate obtained was found to be a good blendstock for clean motor gasoline. Keywords: Liquid membrane, BTX Aromatic, Stirred vesselAbstrakProses membran cair akuatik telah dikembangkan untuk ekstraksi aromatik BTX dari reformat katalitik. Proses tersebut melibatkan permeator multitahap dan dua kolom distilasi sebagai alat utama. Tangki berpengaduk kontinyu digunakan sebagai alat kontak permeasi. Larutan saponin dalam air digunakan sebagai membran cair dan minyak ringan digunakan sebagai fasa penerima. Persamaan-persamaan neraca massa, permeasi dan kendala proses telah diselesaikan untuk mengkaji pengaruh berbagai variabel operasi terhadap perolehan produk dan kemurnian BTX. Kemurnian BTX hingga 95% dan perolehan hingga 90% dapat dicapai. Jika rasio pelarut-terhadap-umpan, laju pengadukan, jumlah tahap permeasi, rasio refluks permeator, atau volume permeator ditingkatkan, maka kebutuhan energi menjadi semakin besar. Energi yang dipasok ke dalam proses didominasi oleh pemulihan pelarut. Rasio pelarut-terhadap-umpan diketahui sebagai variabel yang paling berpengaruh terhadap kebutuhan energi. Kemurnian aromatik BTX semakin meningkat jika laju pengadukan, jumlah tahap permeasi, rasio refluks permeator, atau volume permeator dikurangi. Hal sebaliknya ditemukan untuk nilai perolehan aromatik BTX. Rafinat yang diperoleh diketahui sebagai bahan yang baik untuk gasolin motor ramah lingkungan.Kata kunci: Membran cair, Aromatik BTX, Tangki berpengaduk

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Wu, Xiaoping, Lijuan Zhu, Changhui Zhu, Chenguang Wang, and Quanxin Li. "Catalytic Transformation of Bio-oil to Benzaldehyde and Benzoic Acid: An Approach for the Production of High-value Aromatic Bio-chemicals." Current Green Chemistry 6, no. 2 (October 25, 2019): 135–46. http://dx.doi.org/10.2174/2213346106666190830114619.

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Benzaldehyde and benzoic acid are high-value aromatic chemicals and important intermediates in chemical industry, and the catalytic conversion of biomass-based sources to these aromatic chemicals is of great significance in both academic and industrial fields. This work demonstrated that bio-oil was directionally converted into benzaldehyde and benzoic acid by three-step process under atmospheric pressure and moderate temperatures. The process included the catalytic cracking of biooil into aromatics over 1% Ga/HZSM-5 catalyst, followed by the dealkylation of heavier alkylaromatics to toluene over Re/HY catalyst and the liquid-phase oxidation of toluene-rich aromatics to the targeted chemicals over CoCl2/NHPI (CoCl2/N-Hydroxyphthalimide) catalyst. The production of benzaldehyde and benzoic acid from the bio-oil-derived aromatics, with the overall selectivity of 86.8%, was achieved using CoCl2/NHPI catalyst at 100 °C. Furthermore, adding a small amount of methanol into the feed would efficiently suppress the coke formation, and thus, enhance the yield of aromatics. Potentially, the novel synthesis route offers a green way for the production of higher value-added aromatic chemicals using renewable and environmentally friendly biomass-based sources.

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Aklujkar, Muktak, Carla Risso, Jessica Smith, Derek Beaulieu, Ryan Dubay, Ludovic Giloteaux, Kristin DiBurro, and Dawn Holmes. "Anaerobic degradation of aromatic amino acids by the hyperthermophilic archaeon Ferroglobus placidus." Microbiology 160, no. 12 (December 1, 2014): 2694–709. http://dx.doi.org/10.1099/mic.0.083261-0.

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Ferroglobus placidus was discovered to oxidize completely the aromatic amino acids tyrosine, phenylalanine and tryptophan when Fe(III) oxide was provided as an electron acceptor. This property had not been reported previously for a hyperthermophilic archaeon. It appeared that F. placidus follows a pathway for phenylalanine and tryptophan degradation similar to that of mesophilic nitrate-reducing bacteria, Thauera aromatica and Aromatoleum aromaticum EbN1. Phenylacetate, 4-hydroxyphenylacetate and indole-3-acetate were formed during anaerobic degradation of phenylalanine, tyrosine and tryptophan, respectively. Candidate genes for enzymes involved in the anaerobic oxidation of phenylalanine to phenylacetate (phenylalanine transaminase, phenylpyruvate decarboxylase and phenylacetaldehyde : ferredoxin oxidoreductase) were identified in the F. placidus genome. In addition, transcription of candidate genes for the anaerobic phenylacetate degradation, benzoyl-CoA degradation and glutaryl-CoA degradation pathways was significantly upregulated in microarray and quantitative real-time-PCR studies comparing phenylacetate-grown cells with acetate-grown cells. These results suggested that the general strategies for anaerobic degradation of aromatic amino acids are highly conserved amongst bacteria and archaea living in both mesophilic and hyperthermophilic environments. They also provided insights into the diverse metabolism of Archaeoglobaceae species living in hyperthermophilic environments.

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Berti, G., JE Moore, L. Salusinszky, and D. Seddon. "The Conversion of Light Naphtha Into Aromatics by Using Promoted Zeolite Catalysts." Australian Journal of Chemistry 42, no. 12 (1989): 2095. http://dx.doi.org/10.1071/ch9892095.

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Zeolites of the ZSM-5 family are poor for converting liquid paraffins into aromatics, but commercially available H-ZSM-5 can be effectively promoted with zinc or gallium. A gallium-promoted zeolite was used for the conversion of pentane and a natural-gas condensate into aromatic-rich liquid products. Optimum performance was obtained at temperatures of 475�C and weight-hourly space velocity of 1 h-1. The aromatic products were principally benzene, toluene and xylene, with the benzene content increasing with increasing conversion temperature. Operation of the catalyst at high severity (high temperature, low space velocity) produced a liquid product containing over 90% of aromatics. Lower severity produced less aromatics but higher overall liquid yield.

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Yan, Yingying, David Cabrera-Perez, Jintai Lin, Andrea Pozzer, Lu Hu, Dylan B. Millet, William C. Porter, and Jos Lelieveld. "Global tropospheric effects of aromatic chemistry with the SAPRC-11 mechanism implemented in GEOS-Chem version 9-02." Geoscientific Model Development 12, no. 1 (January 4, 2019): 111–30. http://dx.doi.org/10.5194/gmd-12-111-2019.

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Abstract. The Goddard Earth Observing System with chemistry (GEOS-Chem) model has been updated with the State-wide Air Pollution Research Center version 11 (SAPRC-11) aromatics chemical mechanism, with the purpose of evaluating global and regional effects of the most abundant aromatics (benzene, toluene, xylenes) on the chemical species important for tropospheric oxidation capacity. The model evaluation based on surface and aircraft observations indicates good agreement for aromatics and ozone. A comparison between scenarios in GEOS-Chem with simplified aromatic chemistry (as in the standard setup, with no ozone formation from related peroxy radicals or recycling of NOx) and with the SAPRC-11 scheme reveals relatively slight changes in ozone, the hydroxyl radical, and nitrogen oxides on a global mean basis (1 %–4 %), although remarkable regional differences (5 %–20 %) exist near the source regions. NOx decreases over the source regions and increases in the remote troposphere, due mainly to more efficient transport of peroxyacetyl nitrate (PAN), which is increased with the SAPRC aromatic chemistry. Model ozone mixing ratios with the updated aromatic chemistry increase by up to 5 ppb (more than 10 %), especially in industrially polluted regions. The ozone change is partly due to the direct influence of aromatic oxidation products on ozone production rates, and in part to the altered spatial distribution of NOx that enhances the tropospheric ozone production efficiency. Improved representation of aromatics is important to simulate the tropospheric oxidation.

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Sun, Laizhi, Zhibin Wang, Lei Chen, Shuangxia Yang, Xinping Xie, Mingjie Gao, Baofeng Zhao, Hongyu Si, Jian Li, and Dongliang Hua. "Catalytic Fast Pyrolysis of Biomass into Aromatic Hydrocarbons over Mo-Modified ZSM-5 Catalysts." Catalysts 10, no. 9 (September 12, 2020): 1051. http://dx.doi.org/10.3390/catal10091051.

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Mo-modified ZSM-5 catalysts were prepared and used to produce aromatic hydrocarbons during catalytic fast pyrolysis (CFP) of biomass. The composition and distribution of aromatics were investigated on pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS). The reaction factors, such as the Mo content, the reaction temperature and the catalyst/biomass mass ratio, were also optimized. It was found that the 10Mo/ZSM-5 catalyst displayed the best activity in improving the production of monocyclic aromatic hydrocarbons (MAHs) and decreasing the yield of polycyclic aromatic hydrocarbons (PAHs) at 600 °C and with a catalyst/biomass ratio of 10. Furthermore, according to catalyst characterization and the experiment results, the aromatics formation mechanism over Mo/ZSM-5 catalysts was also summarized and proposed.

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Setiadi, Raka Nugraha Wijaya, and Danestyan Arif Pradana. "Producing monoaromatic compounds from pyrolytic vapour of rice straw using H-ZSM-5/B2O3 catalyst." E3S Web of Conferences 67 (2018): 02026. http://dx.doi.org/10.1051/e3sconf/20186702026.

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The catalytic conversion of rice straw was done to produce mono aromatic compounds. The mixed catalyst of ZSM-5 and B2O3 was obtained through calcination of ZSM-5 and H3BO catalyst mixture. The variation of the composition of the ZSM-5 and B2O3 catalyst was applied in order to test the effect of catalyst composition to the production of mono aromatics compounds. The composition of catalyst used were 15% ZSM-5, 30% ZSM-5, and 100% ZSM-5. Other than the variation of catalyst composition, the variation of the operating temperature of the catalytic conversion also performed in order to study the effect of the temperature to the production of mono aromatic compounds. The catalytic conversion was done at 450, 475, and 500 oC. Experimental results show that the addition of the catalyst resulted in the conversion of oxygenate compounds resulted from the pyrolytic process of rice straw into mono aromatic compounds. It also shows that using 100% ZSM-5 produced the highest yield of mono aromatics compounds. The amount of mono aromatic compounds produced will decrease, as the fraction of ZSM-5 catalyst used and operation temperature also decreased. Using the 100% ZSM-5, the mono aromatics compound with the highest yield is 1, 3 Dimethyl benzene or mxylene.

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Basu, Aditya, Rahul Shrivastava, Bhakti Basu, Shree K. Apte, and Prashant S. Phale. "Modulation of Glucose Transport Causes Preferential Utilization of Aromatic Compounds in Pseudomonas putida CSV86." Journal of Bacteriology 189, no. 21 (September 7, 2007): 7556–62. http://dx.doi.org/10.1128/jb.01235-07.

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ABSTRACT Pseudomonas putida CSV86 utilizes aromatic compounds in preference to glucose and coutilizes aromatics and organic acids. Protein analysis of cells grown on different carbon sources, either alone or in combination, revealed that a 43-kDa periplasmic-space protein was induced by glucose and repressed by aromatics and succinate. Two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometry analysis identified this protein as closely resembling the sugar ABC transporter of Pseudomonas putida KT2440. A partially purified 43-kDa protein showed glucose binding activity and was specific for glucose. The results demonstrate that the aromatic- and organic acid-mediated repression of a periplasmic-space glucose binding protein and consequent inhibition of glucose transport are responsible for this strain's ability to utilize aromatics and organic acids in preference to glucose.

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Wang, Ting, Yuebing Xu, Chengming Shi, Feng Jiang, Bing Liu, and Xiaohao Liu. "Direct production of aromatics from syngas over a hybrid FeMn Fischer–Tropsch catalyst and HZSM-5 zeolite: local environment effect and mechanism-directed tuning of the aromatic selectivity." Catalysis Science & Technology 9, no. 15 (2019): 3933–46. http://dx.doi.org/10.1039/c9cy00750d.

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Foght, J. M., P. M. Fedorak, and D. W. S. Westlake. "Mineralization of [14C]hexadecane and [14C]phenanthrene in crude oil: specificity among bacterial isolates." Canadian Journal of Microbiology 36, no. 3 (March 1, 1990): 169–75. http://dx.doi.org/10.1139/m90-030.

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Bacteria isolated from freshwater, marine, and estuarine samples were tested for the ability to produce 14CO2 from n-[1-14C]hexadecane or [9-14C]phenanthrene added to Prudhoe Bay crude oil. Of 138 isolates tested, 54 (39%) mineralized the model aliphatic compound hexadecane and 6 (4%) mineralized the model aromatic compound phenanthrene. None mineralized both compounds. There was no apparent correlation between degradative ability and genus or source. Additional hydrocarbon-degrading bacteria from diverse sources were tested and found to mineralize either hexadecane or phenanthrene. Of 61 hexadecane- and 21 phenanthrene-mineralizing bacteria tested, none mineralized both model compounds. Selected isolates and commercially available cultures were tested for mineralization of specific 14C-labelled mono-, di-, and tri-cyclic aromatics. An apparent hierarchy of degradation was observed: strains mineralizing the mono- and di-cyclic aromatics toluene and naphthalene did not mineralize biphenyl or the tricyclic aromatics anthracene and phenanthrene, whereas those strains that mineralized the tricyclic aromatics also mineralized the smaller substrates. Similarly, not all n-alkane-mineralizing isolates tested mineralized the isoprenoid pristane. A combined culture consisting of one aliphatic- and one aromatic-degrading isolate was tested for mineralization of the model compounds and for degradation of other crude oil components by gas chromatography. No synergism or antagonism was observed compared with degradation by the individual isolates. Key words: aromatic, aliphatic, bioegradation, petroleum.

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Zhang, Lingling, Hong Yi, Jue Wang, and Aiwen Lei. "Visible-light induced oxidative Csp3–H activation of methyl aromatics to methyl esters." Green Chemistry 18, no. 19 (2016): 5122–26. http://dx.doi.org/10.1039/c6gc01880g.

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A mild and catalytic oxidative Csp³–H activation of methyl aromatics using O₂via photocatalysis has been achieved. A lot of methyl aromatics can be tolerated, providing a route for aromatic methyl carboxylates. In addition, this protocol can be performed on a gram scale.

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Pourjafar, Mohammad, Amir Khosravani, and Rabi Behrooz. "Formation mechanism of aromatics during co-pyrolysis of coal and cotton stalk." BioResources 15, no. 2 (April 27, 2020): 4449–63. http://dx.doi.org/10.15376/biores.15.2.4449-4463.

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Pyrolysis experiments were conducted in a tubular furnace from room temperature to 600 °C at 5 °C /min, and kept for 15 min. The light tar was then derived from the liquid products of pyrolysis by n-hexane supersonic extraction. Gas chromatography–mass spectrometry was employed to analyze the light tars from cotton stalk (CS) pyrolysis, Shenmu coal (SM) pyrolysis, and co-pyrolysis of CS/SM. Microcrystalline cellulose (MCC) was selected as a model compound, and the light tar from co-pyrolysis tar of MCC/SM was investigated for comparison. The results indicated that CS improved the yields and quality of phenols and benzenes in co-pyrolysis tar and that MCC had excellent performance in the formation of mononuclear aromatics during the co-pyrolysis of MCC/SM. Based on the pyrolytic behavior of CS and SM, the mechanisms of aromatic formation were further determined. It was shown that the free radicals that cracked from CS accelerated the formation of aromatics. The alkyl and mononuclear aromatic radicals of CS pyrolysis combined with the radicals from the SM aromatic structure, which then converted to benzenes and phenols. Finally, the most favorable reaction routes of mononuclear aromatics formation were proposed.

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Correia, Isabel, Jo�o Costa Pessoa, M. Teresa Duarte, M. F�tima Minas da Piedade, Tam�s Jackush, Tam�s Kiss, M. Margarida C. A. Castro, Carlos F. G. C. Geraldes, and Fernando Avecilla. "Vanadium(IV andV) Complexes of Schiff Bases and Reduced Schiff Bases Derived from the Reaction of Aromatico-Hydroxyaldehydes and Diamines: Synthesis, Characterisation and Solution Studies." European Journal of Inorganic Chemistry 2005, no. 4 (February 2005): 732–44. http://dx.doi.org/10.1002/ejic.200400481.

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Wang, Weiyan, Zhiqiang Qiao, Kun Zhang, Pengli Liu, Yunquan Yang, and Kui Wu. "Highly selective catalytic hydrodeoxygenation of Caromatic–OH in bio-oil to cycloalkanes on a Ce–Ni–W–B amorphous catalyst." RSC Adv. 4, no. 70 (2014): 37288–95. http://dx.doi.org/10.1039/c4ra04364b.

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Ce–Ni–W–B amorphous catalysts exhibited high activity in the hydrodeoxygenation (HDO) of C_aromatic–OH. The deoxygenation degree was up to 98.1% with low aromatics selectivity at 498 K. Both the aromatics content and reaction temperature were decreased, which realized the energy saving and consumption reduction in the HDO process.

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Präsang, C., A. Mlodzianowska, G. Geiseler, W. Massa, M. Hofmann, and A. Berndt. "Two-electron aromatics containing three and four adjacent boron atoms." Pure and Applied Chemistry 75, no. 9 (January 1, 2003): 1175–82. http://dx.doi.org/10.1351/pac200375091175.

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A two-electron aromatic bis (tris-trimethylsilylmethylene)-substituted tetraborane(4) was found to be a useful precursor for the synthesis of two-electron aromatic tetraboranes(6), triboracyclopropanates,as well as tetraboranes(6) distorted toward triboracyclopropanates with boryl bridges. Bishomo two-electron aromatics with a borata bridge and a protonated borata bridge, respectively, are also presented.

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Veličković, Dušan, Mowei Zhou, Jonathan S. Schilling, and Jiwei Zhang. "Using MALDI-FTICR-MS Imaging to Track Low-Molecular-Weight Aromatic Derivatives of Fungal Decayed Wood." Journal of Fungi 7, no. 8 (July 28, 2021): 609. http://dx.doi.org/10.3390/jof7080609.

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Low-molecular-weight (LMW) aromatics are crucial in meditating fungal processes for plant biomass decomposition. Some LMW compounds are employed as electron donors for oxidative degradation in brown rot (BR), an efficient wood-degrading strategy in fungi that selectively degrades carbohydrates but leaves modified lignins. Previous understandings of LMW aromatics were primarily based on “bulk extraction”, an approach that cannot fully reflect their real-time functions during BR. Here, we applied an optimized molecular imaging method that combines matrix-assisted laser desorption ionization (MALDI) with Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS) to directly measure the temporal profiles of BR aromatics as Rhodonia placenta decayed a wood wafer. We found that some phenolics were pre-existing in wood, while some (e.g., catechin-methyl ether and dihydroxy-dimethoxyflavan) were generated immediately after fungal activity. These pinpointed aromatics might be recruited to drive early BR oxidative mechanisms by generating Fenton reagents, Fe2+ and H2O2. As BR progressed, ligninolytic products were accumulated and then modified into various aromatic derivatives, confirming that R. placenta depolymerizes lignin. Together, this work confirms aromatic patterns that have been implicated in BR fungi, and it demonstrates the use of MALDI-FTICR-MS imaging as a new approach to monitor the temporal changes of LMW aromatics during wood degradation.

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Ma, Yanjun, Timothy J. Donohue, and Daniel R. Noguera. "Kinetic modeling of anaerobic degradation of plant-derived aromatic mixtures by Rhodopseudomonas palustris." Biodegradation 32, no. 2 (March 6, 2021): 179–92. http://dx.doi.org/10.1007/s10532-021-09932-3.

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AbstractRhodopseudomonas palustris is a model microorganism for studying the anaerobic metabolism of aromatic compounds. While it is well documented which aromatics can serve as sole organic carbon sources, co-metabolism of other aromatics is poorly understood. This study used kinetic modeling to analyze the simultaneous degradation of aromatic compounds present in corn stover hydrolysates and model the co-metabolism of aromatics not known to support growth of R. palustris as sole organic substrates. The simulation predicted that p-coumaroyl amide and feruloyl amide were hydrolyzed to p-coumaric acid and ferulic acid, respectively, and further transformed via p-coumaroyl-CoA and feruloyl-CoA. The modeling also suggested that metabolism of p-hydroxyphenyl aromatics was slowed by substrate inhibition, whereas the transformation of guaiacyl aromatics was inhibited by their p-hydroxyphenyl counterparts. It also predicted that substrate channeling may occur during degradation of p-coumaroyl-CoA and feruloyl-CoA, resulting in no detectable accumulation of p-hydroxybenzaldehyde and vanillin, during the transformation of these CoA ligated compounds to p-hydroxybenzoic acid and vanillic acid, respectively. While the simulation correctly represented the known transformation of p-hydroxybenzoic acid via the benzoyl-CoA pathway, it also suggested co-metabolism of vanillic acid and syringic acid, which are known not to serve as photoheterotrophic growth substrate for R. palustris.

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Cai, Yuanting, Yuhui Hua, Zhengyu Lu, Qing Lan, Zuzhang Lin, Jiawei Fei, Zhixin Chen, Hong Zhang, and Haiping Xia. "Electrophilic aromatic substitution reactions of compounds with Craig-Möbius aromaticity." Proceedings of the National Academy of Sciences 118, no. 39 (September 20, 2021): e2102310118. http://dx.doi.org/10.1073/pnas.2102310118.

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Electrophilic aromatic substitution (EAS) reactions are widely regarded as characteristic reactions of aromatic species, but no comparable reaction has been reported for molecules with Craig-Möbius aromaticity. Here, we demonstrate successful EAS reactions of Craig-Möbius aromatics, osmapentalenes, and fused osmapentalenes. The highly reactive nature of osmapentalene makes it susceptible to electrophilic attack by halogens, thus osmapentalene, osmafuran-fused osmapentalene, and osmabenzene-fused osmapentalene can undergo typical EAS reactions. In addition, the selective formation of a series of halogen substituted metalla-aromatics via EAS reactions has revealed an unprecedented approach to otherwise elusive compounds such as the unsaturated cyclic chlorirenium ions. Density functional theory calculations were conducted to study the electronic effect on the regioselectivity of the EAS reactions.

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Basu, Aditya, Shree K. Apte, and Prashant S. Phale. "Preferential Utilization of Aromatic Compounds over Glucose by Pseudomonas putida CSV86." Applied and Environmental Microbiology 72, no. 3 (March 2006): 2226–30. http://dx.doi.org/10.1128/aem.72.3.2226-2230.2006.

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ABSTRACT Pseudomonas putida CSV86, a naphthalene-degrading organism, exhibited diauxic growth on aromatic compounds plus glucose, with utilization of aromatics in the first log phase and of glucose in the second log phase. Glucose supplementation did not suppress the activity of degrading enzymes, which were induced upon addition of aromatic compounds. The induction was inhibited by chloramphenicol, suggesting that de novo protein synthesis was essential. Cells showed cometabolism of aromatic compounds and organic acids; however, organic acids suppressed glucose utilization.

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Krompiec, Stanisław, Aneta Kurpanik-Wójcik, Marek Matussek, Bogumiła Gołek, Angelika Mieszczanin, and Aleksandra Fijołek. "Diels–Alder Cycloaddition with CO, CO2, SO2, or N2 Extrusion: A Powerful Tool for Material Chemistry." Materials 15, no. 1 (December 27, 2021): 172. http://dx.doi.org/10.3390/ma15010172.

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Phenyl, naphthyl, polyarylphenyl, coronene, and other aromatic and polyaromatic moieties primarily influence the final materials’ properties. One of the synthetic tools used to implement (hetero)aromatic moieties into final structures is Diels–Alder cycloaddition (DAC), typically combined with Scholl dehydrocondensation. Substituted 2-pyranones, 1,1-dioxothiophenes, and, especially, 1,3-cyclopentadienones are valuable substrates for [4 + 2] cycloaddition, leading to multisubstituted derivatives of benzene, naphthalene, and other aromatics. Cycloadditions of dienes can be carried out with extrusion of carbon dioxide, carbon oxide, or sulphur dioxide. When pyranones, dioxothiophenes, or cyclopentadienones and DA cycloaddition are aided with acetylenes including masked ones, conjugated or isolated diynes, or polyynes and arynes, aromatic systems are obtained. This review covers the development and the current state of knowledge regarding thermal DA cycloaddition of dienes mentioned above and dienophiles leading to (hetero)aromatics via CO, CO2, or SO2 extrusion. Particular attention was paid to the role that introduced aromatic moieties play in designing molecular structures with expected properties. Undoubtedly, the DAC variants described in this review, combined with other modern synthetic tools, constitute a convenient and efficient way of obtaining functionalized nanomaterials, continually showing the potential to impact materials sciences and new technologies in the nearest future.

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Abonia, Rodrigo, Juan Castillo, Paola Cuervo, Braulio Insuasty, Jairo Quiroga, Alejandro OrtÃz, Manuel Nogueras, and Justo Cobo. "A Simple One-Pot Synthesis of New Imidazol-2-yl-1H-quinolin-2-ones from the Direct Reaction of 2-Chloroquinolin-3-carbaldehyde with Aromatico-Diamines." European Journal of Organic Chemistry 2010, no. 2 (January 2010): 317–25. http://dx.doi.org/10.1002/ejoc.200901014.

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Chen, Yaqi, Tao Li, Jianguo Li, Shiyan Cheng, Jinghui Wang, Chandra Verma, Yibing Zhao, and Chuanliu Wu. "Stabilization of peptides against proteolysis through disulfide-bridged conjugation with synthetic aromatics." Organic & Biomolecular Chemistry 15, no. 8 (2017): 1921–29. http://dx.doi.org/10.1039/c6ob02786e.

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We developed an efficient strategy for the stabilization of peptides against proteolysis, which involves noncovalent π–π interactions between aromatic amino acid residues in peptides and synthetic electron-deficient aromatics.

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Diederich, François, and Carlo Thilgen. "Preface." Pure and Applied Chemistry 82, no. 4 (January 1, 2010): iv. http://dx.doi.org/10.1351/pac20108204iv.

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The 13th International Symposium on Novel Aromatic Compounds (ISNA-13) was held in Luxembourg City, Grand-Duchy of Luxembourg, the smallest country so far hosting a conference of the ISNA series. It took place 19-24 July 2009 and was attended by 360 participants, mostly from academic institutions, representing 34 countries. The scientific program consisted of the Opening Plenary Lecture given by Prof. Jean-Marie Lehn (Institute of Science and Supramolecular Engineering and Louis Pasteur University, Strasbourg), the 2009 Nozoe Lecture presented by Prof. Atsuhiro Osuka (Kyoto University, Kyoto), 34 invited lectures, 26 oral communications, and 194 posters presented in two sessions. In a public lecture, vice rector Prof. Luciënne Blessing presented the activities of the recently founded University of Luxembourg. The organizing committee made a strong and successful effort to attract numerous graduate and undergraduate students to ISNA-13.The ISNA symposium series was launched by Prof. Tetsuo Nozoe in 1970 as the International Symposium on Nonbenzenoid Aromatic Compounds. Since then, the currently biennial conference rotates between Asia, North America, and Europe. As indicated by its present name, the focus of the symposium has broadened and is now set on new experimental and theoretical insights into the concept of aromaticity, synthesis and properties of novel aromatic compounds, as well as applications of π-conjugated systems in different fields of molecular science and technology. From a broader perspective, through interactions between participating scientists, ISNA conferences aim at the generation of new knowledge and its eventual application for the betterment of society.In line with the above, the organizers of ISNA-13 emphasized not only the traditional and fundamental aspects of novel aromatic compounds, such as their theory, synthesis, structure, and properties, but also their application in materials science. This included, for example, macrocycles, oligomers, and polymers and their optoelectronic properties, supramolecular chemistry based on aromatic functional modules, aromatics on surfaces, and molecular electronics based on aromatic units. The main subjects of the meeting that are covered in this Special Topic issue are as follows:- aromaticity and novel aromatic systems - theory- aromaticity and novel aromatic systems - experimental- fullerenes and concave aromatics- aromatic polymers and oligomers and their optoelectronic properties- supramolecular aromatic devices, switches, and machines- aromatics on surfaces, including graphene- optoelectronicsThe next conference, ISNA-14, will be chaired by Profs. Michael M. Haley (University of Oregon, Eugene) and Benjamin T. King (University of Nevada, Reno) and will be held in Eugene, OR, USA, 24-29 July 2011. ISNA-15 will be organized by Prof. Ken-Tsung Wong (National Taiwan University) in Taipei, Taiwan.François DiederichA. Dieter SchlüterCarlo ThilgenConference Editors

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Qiu, Rulin, and Jun Zhu. "Adaptive aromaticity in 16-valence-electron metallazapentalenes." Dalton Transactions 50, no. 45 (2021): 16842–48. http://dx.doi.org/10.1039/d1dt03244e.

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Theoretical studies reveal that metallazapentalenes display rare adaptive aromaticity (being aromatic in both the S0 and T1 states) whereas metalloxapentalenes exhibit nonaromaticity in these two states, expanding the family of adaptive aromatics.

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Togo, Hideo, and Sousuke Ushijima. "One-Pot Conversion of Aromatic Bromides and Aromatics into Aromatic Nitriles." Synlett 2010, no. 10 (May 10, 2010): 1562–66. http://dx.doi.org/10.1055/s-0029-1219935.

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Wei, Zhimin, Youming Li, and Yi Hou. "Quick estimation for pollution load contributions of aromatic organics in wastewater from pulp and paper industry." Nordic Pulp & Paper Research Journal 33, no. 3 (September 25, 2018): 568–72. http://dx.doi.org/10.1515/npprj-2018-3046.

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Abstract Quick and accurate estimation of organic pollution load such as COD in wastewater is very important for the implementation of cleaner production, especially in pulp and paper industry. In order to find the contribution of pollution load of aromatic organics, several non-aromatic and aromatic organics were studied. Results indicated that there was a good linear correlation between theoretical COD (ThOD) and composite parameters of ln(C + H)/O, which is calculated from the amount of C, H and O atoms in the molecular formula. From the regression line equation of ThOD vs ln(C + H)/O, it is found that the gradient of the aromatic ring regression line is lower than that of other acyclic compounds, which may be ascribed to aromatics which were hard to oxidize in measurements of COD. An actual COD well matched to the ThOD estimated for common aromatics with phenolic and non-phenolic structures often appeared for wastewater from pulp and paper industry, with a relative error rate of ± 5 %. Ideal recovery rates of these, 95 % to 105 %, were achieved. This work provides an effective method for quick and accurate estimation for pollution load contributions, which is important for contamination control and progress in industry.

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41

Šmídl, Petr, and Karel Pecka. "Chromatographic behaviour of aromatic hydrocarbons and heterocyclic compounds on silica gel with a chemically bonded amino phase." Collection of Czechoslovak Chemical Communications 50, no. 11 (1985): 2375–80. http://dx.doi.org/10.1135/cccc19852375.

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The chromatographic behaviour of a series of polycyclic aromatic hydrocarbons and heterocyclic compounds was investigated on Separon SIX NH2, a sorbent with chemically bonded amino groups. The effect of substitution and partial hydrogenation of the aromatics on their retention was examined. The achieved separation of aromatic hydrocarbons from their mixtures into groups, each containing substances with the same number of rings, was compared with that published for other, similar chromatographic materials. The effect of structure of some heterocyclic compounds on their affinity for the stationary phase, in comparison with the related aromatic hydrocarbons, is also discussed.

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Fedik, Nikita, Alexander I. Boldyrev, and Alvaro Muñoz-Castro. "Aromatic character of [Au13]5+ and [MAu12]4+/6+ (M = Pd, Pt) cores in ligand protected gold nanoclusters – interplay between spherical and planar σ-aromatics." Physical Chemistry Chemical Physics 21, no. 45 (2019): 25215–19. http://dx.doi.org/10.1039/c9cp04477a.

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Ligand-protected superatoms are able to behave as both spherical and planar aromatic species, providing a strong link between spherical and planar σ-aromatics, which can be controlled selectively by tuning their redox charge states.

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Sadowsky, Daniel, Kristopher McNeill, and Christopher J. Cramer. "Dehalogenation of Aromatics by Nucleophilic Aromatic Substitution." Environmental Science & Technology 48, no. 18 (August 27, 2014): 10904–11. http://dx.doi.org/10.1021/es5028822.

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Toda, Hayato, Nobuyuki Hara, Michiya Fujiki, and Yoshitane Imai. "Sign inversion in magnetic circularly polarised luminescence of fused aromatics with 1.6 T N-up/S-up Faraday geometry." RSC Advances 11, no. 3 (2021): 1581–85. http://dx.doi.org/10.1039/d0ra09233a.

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Diamagnetic fused aromatics exhibit mirror-symmetric magnetic circularly polarised luminescence (MCPL) depend on either the aromatic structures or the peripheral positions of the substituents through N-up and S-up Faraday geometries under a 1.6 T magnetic field.

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ARZHANIK, VLADIMIR, DARJA SVISTUNOVA, OLEG KOLIASNIKOV, and ALEXEY M. EGOROV. "INTERACTION OF ANTIBODIES WITH AROMATIC LIGANDS: THE ROLE OF π-STACKING." Journal of Bioinformatics and Computational Biology 08, no. 03 (June 2010): 471–83. http://dx.doi.org/10.1142/s0219720010004835.

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Antibodies are responsible for antigen recognition in vertebrate organisms. Practically any molecule can be bound by antibodies. In this work structures of 73 complexes of antibodies with small antigens were taken from PDB database and compared. The main epitope of studied ligands was an aromatic ring. Antibodies bound it with a deep cavity, lying between complementary determining regions (CDR) H3 and L3 and formed by aromatic residues. In most cases the aromatic ring of ligand was placed parallel to one or two aromatic sidechains of binding site at 3.5-4 Angstrom distance. This disposition of aromatic rings is a sign of the presence of π-stacking. It was found that small ligands with aromatics area percentage > 36% predominantly form π-stacking interaction with antibodies. Most often this interaction was observed for residues in positions H33, H95, L32 and L93.

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Wang, Wenbo, Zhongyang Luo, Simin Li, Shuang Xue, and Haoran Sun. "Novel Micro-Mesoporous Composite ZSM-5 Catalyst for Aromatics Production by Catalytic Fast Pyrolysis of Lignin Residues." Catalysts 10, no. 4 (April 1, 2020): 378. http://dx.doi.org/10.3390/catal10040378.

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The industrial utilization of lignocellulosic biomass is often accompanied by lots of lignin residues. Catalytic fast pyrolysis (CFP) is a high-throughput method to convert lignin to aromatics and phenolics. In order to optimize catalytic performance, conventional zeolite catalysts often need to have mesostructural modification. Here, based on hierarchical zeolite (HZ), a novel micro-mesoporous composite zeolite was obtained by redeposition under mild conditions. The conversion of two industrial lignin residues, Kraft Lignin (KL) and Pyrolytic Lignin (PL), was investigated. Interestingly, the hierarchical sample was more suitable for the case of higher concentration of primary pyrolysis products such as CFP of PL, with aromatics yield of 12.7 wt % and a monocyclic aromatic hydrocarbons (MAHs) to polycyclic aromatic hydrocarbons (PAHs) mass ratio of 4.86. The mesoporous composite zeolite possessed a better PAHs suppression capability as M/P reached 6.06, and was suitable for low reactants’ concentration and high oxygen content, such as KL CFP, with a higher aromatics yield of 3.3 wt % and M/P of 5.12. These results were compared with poplar sawdust as actual biomass, and mesoporous samples were both highly efficient catalysts with MAHs yield over 10 wt % and M/P around 5.

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Axelsson, Håkan, Anders Eilard, Annika Emanuelsson, Bo Galle, Hans Edner, Pär Ragnarson, and Henrik Kloo. "Measurement of Aromatic Hydrocarbons with the DOAS Technique." Applied Spectroscopy 49, no. 9 (September 1995): 1254–60. http://dx.doi.org/10.1366/0003702953965254.

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Long-path DOAS (differential optical absorption spectroscopy) in the ultraviolet spectral region has been shown to be applicable for low-concentration measurements of light aromatic hydrocarbons. However, because of spectral interferences among different aromatics as well as with oxygen, ozone, and sulfur dioxide, the application of the DOAS technique for this group of components is not without problems. This project includes a study of the differential absorption characteristics, between 250 and 280 nm, of twelve light aromatic hydrocarbons representing major constituents in technical solvents used in the automobile industry. Spectral overlapping between the different species, including oxygen, ozone, and sulfur dioxide, has been investigated and related to the chemical structure of the different aromatics. Interference effects in the DOAS application due to spectral overlapping have been investigated both in quantitative and in qualitative terms, with data from a field campaign at a major automobile manufacturing plant.

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McKee, Richard H., Ceinwen A. Schreiner, Russell White, Mark Saperstein, Jeffrey H. Charlap, Thomas P. O'Neill, Katy Olsavsky Goyak, and Mark Nicolich. "Characterization of the Noncancer Hazards of Gas Oils." International Journal of Toxicology 33, no. 1_suppl (October 31, 2013): 78S—94S. http://dx.doi.org/10.1177/1091581813504228.

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Gas oils, used to manufacture diesel fuel and residential heating oil, are complex hydrocarbon substances with carbon numbers of C9-C30 and boiling ranges of approximately 150°C to 450°C. Target organ (liver enlargement, reduced thymus weights, and reductions in hematological parameters) and developmental (reduced fetal viability, increased resorption frequency, and reduced fetal weights) effects are associated with aromatic constituents present in some gas oils. Two types of gas oils were tested for repeated-dose and developmental toxicity following repeated dermal administration. A blend of commercial diesel fuels containing 26% aromatics, primarily single-ring compounds, did not cause either target organ or developmental effects at levels up to 600 mg/kg/d. “Cracked” gas oils containing higher levels of aromatic constituents were also tested. Because of limited sample availability, 2 cracked gas oil samples were tested, one for systemic effects and the other for developmental toxicity. The sample tested in the repeated-dose toxicity study (81% aromatics including approximately 10% 3-ring compounds) produced increased liver weights, reduced thymus weights, and reductions in hematological parameters. The overall no observed adverse effect level (NOAEL) was 100 mg/kg/d. The sample tested for developmental toxicity (65% aromatics including approximately 5% 3-ring compounds) resulted in significant reductions in fetal survival, significant increases in resorption frequency, and significant reductions in fetal weights with an overall NOAEL of 100 mg/kg/d. In summary, gas oils may or may not cause target organ and/or developmental effects depending on the levels and types of aromatic constituents that they contain.

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Zhou, Haifeng, Yasuhiro Uozumi, Danyi Chen, Yanmei Zhou, Sensheng Liu, Qixing Liu, and Kaili Zhang. "Metal-free Reduction of Nitro Aromatics to Amines with B2(OH)4/H2O." Synlett 29, no. 13 (June 19, 2018): 1765–68. http://dx.doi.org/10.1055/s-0037-1610086.

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A metal-free reduction of nitro aromatics mediated by diboronic acid with water as both the hydrogen donor and solvent under mild conditions has been developed. A series of aromatic amines were obtained with good functional group tolerance and in good yields.

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Peng, Jianfei, Min Hu, Zhuofei Du, Yinhui Wang, Jing Zheng, Wenbin Zhang, Yudong Yang, et al. "Gasoline aromatics: a critical determinant of urban secondary organic aerosol formation." Atmospheric Chemistry and Physics 17, no. 17 (September 13, 2017): 10743–52. http://dx.doi.org/10.5194/acp-17-10743-2017.

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Abstract. Gasoline vehicle exhaust is an important contributor to secondary organic aerosol (SOA) formation in urban atmosphere. Fuel composition has a potentially considerable impact on gasoline SOA production, but the link between fuel components and SOA production is still poorly understood. Here, we present chamber experiments to investigate the impacts of gasoline aromatic content on SOA production through chamber oxidation approach. A significant amplification factor of 3–6 for SOA productions from gasoline exhausts is observed as gasoline aromatic content rose from 29 to 37 %. Considerably higher emission of aromatic volatile organic compounds (VOCs) using high-aromatic fuel plays an essential role in the enhancement of SOA production, while semi-volatile organic compounds (e.g., gas-phase PAHs) may also contribute to the higher SOA production. Our findings indicate that gasoline aromatics significantly influence ambient PM2. 5 concentration in urban areas and emphasize that more stringent regulation of gasoline aromatic content will lead to considerable benefits for urban air quality.

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Journal articles on the topic 'Aromatico'

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