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Journal articles on the topic 'Aromatic system'

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Published: 18 May 2024

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1

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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2

Wu, Weihua, Fang Liu, and Seema Singh. "Toward engineeringE. coliwith an autoregulatory system for lignin valorization." Proceedings of the National Academy of Sciences 115, no. 12 (March 2, 2018): 2970–75. http://dx.doi.org/10.1073/pnas.1720129115.

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Efficient lignin valorization could add more than 10-fold the value gained from burning it for energy and is critical for economic viability of future biorefineries. However, lignin-derived aromatics from biomass pretreatment are known to be potent fermentation inhibitors in microbial production of fuels and other value-added chemicals. In addition, isopropyl-β-d-1-thiogalactopyranoside and other inducers are routinely added into fermentation broth to induce the expression of pathway enzymes, which further adds to the overall process cost. An autoregulatory system that can diminish the aromatics’ toxicity as well as be substrate-inducible can be the key for successful integration of lignin valorization into future lignocellulosic biorefineries. Toward that goal, in this study an autoregulatory system is demonstrated that alleviates the toxicity issue and eliminates the cost of an external inducer. Specifically, this system is composed of a catechol biosynthesis pathway coexpressed with an active aromatic transporter CouP under induction by a vanillin self-inducible promoter, ADH7, to effectively convert the lignin-derived aromatics into value-added chemicals usingEscherichia colias a host. The constructed autoregulatory system can efficiently transport vanillin across the cell membrane and convert it to catechol. Compared with the system without CouP expression, the expression of catechol biosynthesis pathway with transporter CouP significantly improved the catechol yields about 30% and 40% under promoter pTrc and ADH7, respectively. This study demonstrated an aromatic-induced autoregulatory system that enabled conversion of lignin-derived aromatics into catechol without the addition of any costly, external inducers, providing a promising and economically viable route for lignin valorization.

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3

IWANAMI, Hiroshi. "Aromatic Utilization System in Building." Journal of the Society of Powder Technology, Japan 29, no. 2 (1992): 124–28. http://dx.doi.org/10.4164/sptj.29.124.

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4

Minot, C. "Graphite as an aromatic system." Journal of Physical Chemistry 91, no. 25 (December 1987): 6380–85. http://dx.doi.org/10.1021/j100309a013.

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5

Molčanov, Krešimir, and Biserka Kojić-Prodić. "Towards understanding π-stacking interactions between non-aromatic rings." IUCrJ 6, no. 2 (February 2, 2019): 156–66. http://dx.doi.org/10.1107/s2052252519000186.

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The first systematic study of π interactions between non-aromatic rings, based on the authors' own results from an experimental X-ray charge-density analysis assisted by quantum chemical calculations, is presented. The landmark (non-aromatic) examples include quinoid rings, planar radicals and metal-chelate rings. The results can be summarized as: (i) non-aromatic planar polyenic rings can be stacked, (ii) interactions are more pronounced between systems or rings with little or no π-electron delocalization (e.g. quinones) than those involving delocalized systems (e.g. aromatics), and (iii) the main component of the interaction is electrostatic/multipolar between closed-shell rings, whereas (iv) interactions between radicals involve a significant covalent contribution (multicentric bonding). Thus, stacking covers a wide range of interactions and energies, ranging from weak dispersion to unlocalized two-electron multicentric covalent bonding (`pancake bonding'), allowing a face-to-face stacking arrangement in some chemical species (quinone anions). The predominant interaction in a particular stacked system modulates the physical properties and defines a strategy for crystal engineering of functional materials.

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6

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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7

Salter, M., R. G. Knowles, and C. I. Pogson. "Transport of the aromatic amino acids into isolated rat liver cells. Properties of uptake by two distinct systems." Biochemical Journal 233, no. 2 (January 15, 1986): 499–506. http://dx.doi.org/10.1042/bj2330499.

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The transport of the aromatic amino acids into isolated rat liver cells was studied. There was a rapid and substantial binding of the aromatic amino acids, L-alanine and L-leucine to the plasma membrane. This has important consequences for the determination of rates of transport and intracellular concentrations of the amino acids. Inhibition studies with a variety of substrates of various transport systems gave results consistent with aromatic amino acid transport being catalysed by two systems: a 2-aminobicyclo(2,2,1)heptane-2-carboxylic acid (BCH)-insensitive aromatic D- and L-amino acid-specific system, and the L-type system (BCH-sensitive). The BCH-insensitive component of transport was Na+-independent and facilitated non-concentrative transport of the aromatic amino acids; it was unaffected by culture of liver cells for 24 h, by 48 h starvation, dexamethasone phosphate or glucagon. Kinetic properties of the BCH-inhibitable component were similar to those previously reported for the L2-system in liver cells. The BCH-insensitive component was a comparatively low-Km low-Vmax. transport system that we suggest is similar to the T-transport system previously seen only in human red blood cells. The results are discussed with reference to the importance of the T- and L-systems in the control of aromatic L-amino acid degradation in the liver.

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8

Nogi, Keisuke, and Hideki Yorimitsu. "Aromatic metamorphosis: conversion of an aromatic skeleton into a different ring system." Chemical Communications 53, no. 29 (2017): 4055–65. http://dx.doi.org/10.1039/c7cc00078b.

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9

Bernstein, Max. "Reactions of aromatics in space and connections to the carbon chemistry of Solar System materials." Proceedings of the International Astronomical Union 4, S251 (February 2008): 437–40. http://dx.doi.org/10.1017/s1743921308022102.

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AbstractPolycyclic aromatic hydrocarbons (PAHs) and related aromatic materials are thought to be the most abudant class of organic carbon in the universe, being present in virtually all phases of the ISM, and abundant in carbonaceous meteorites and asteroid and comet dust. The basic PAH skeleton is proposed to have formed in outflows of carbon rich stars, and isotopic measurements of extraterrestrial graphitic carbon is consistent with this notion. However, functionalized aromatics bearing oxygen atoms, aliphatic domains, and deuterium enrichments have been extracted from meteorites and more recently been measured in IDPs and Stardust retuned comet samples. Exposure of remnant circumstellar PAHs to energetic processing at low temperature in the presense of H2O is the most parsimonious explanation for these observations.We will present laboratory infrared spectra of various aromatic species and PAH cations in solid H2O under conditions relevant for comparsion to absorptions attributed to PAHs observed towards objects embedded in dense clouds. In addition, we shall describe the reactions of PAHs under these conditions in the lab when they are exposed to energetic processing. Finally, we will propose a mechanism, and make specific predictions regarding the structures and distribution of deuterium that should be observed in extraterrestrial samples if low temperature ice radiation chemistry is playing a role in the formation of the molecules seen in Solar System materials.

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10

Zhu, Congqing, Qin Zhu, Jinglan Fan, Jun Zhu, Xumin He, Xiao-Yu Cao, and Haiping Xia. "A Metal-Bridged Tricyclic Aromatic System: Synthesis of Osmium Polycyclic Aromatic Complexes." Angewandte Chemie International Edition 53, no. 24 (April 29, 2014): 6232–36. http://dx.doi.org/10.1002/anie.201403245.

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11

Zhu, Congqing, Qin Zhu, Jinglan Fan, Jun Zhu, Xumin He, Xiao-Yu Cao, and Haiping Xia. "A Metal-Bridged Tricyclic Aromatic System: Synthesis of Osmium Polycyclic Aromatic Complexes." Angewandte Chemie 126, no. 24 (April 29, 2014): 6346–50. http://dx.doi.org/10.1002/ange.201403245.

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12

Li, Wen-Wen, Jia-Lin Zhao, Ze-Yu Wang, Pei-Ting Li, Zi-Fa Shi, Xiao-Ping Cao, and Qiang Liu. "A Paternò–Büchi Reaction of Aromatics with Quinones under Visible Light Irradiation." Molecules 29, no. 7 (March 28, 2024): 1513. http://dx.doi.org/10.3390/molecules29071513.

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Reported herein is a Paternò–Büchi reaction of aromatic double bonds with quinones under visible light irradiation. The reactions of aromatics with quinones exposed to blue LED irradiation yielded oxetanes at −78 °C, which was attributed to both the activation of double bonds in aromatics and the stabilization of oxetanes by thiadiazole, oxadiazole, or selenadiazole groups. The addition of Cu(OTf)2 to the reaction system at room temperature resulted in the formation of diaryl ethers via the copper-catalyzed ring opening of oxetanes in situ. Notably, the substrate scope was extended to general aromatics.

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13

Prakash, K., F. R. Islam, K. A. Mamun, and H. R. Pota. "Configurations of Aromatic Networks for Power Distribution System." Sustainability 12, no. 10 (May 25, 2020): 4317. http://dx.doi.org/10.3390/su12104317.

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A distribution network is one of the main parts of a power system that distributes power to customers. While there are various types of power distribution networks, a recently introduced novel structure of an aromatic network could begin a new era in the distribution levels of power systems and designs of microgrids or smart grids. In order to minimize blackout periods during natural disasters and provide sustainable energy, improve energy efficiency and maintain stability of a distribution network, it is essential to configure/reconfigure the network topology based on its geographical location and power demand, and also important to realize its self-healing function. In this paper, a strategy for reconfiguring aromatic networks based on structures of natural aromatic molecules is explained. Various network structures are designed, and simulations have been conducted to justify the performance of each configuration. It is found that an aromatic network does not need to be fixed in a specific configuration (i.e., a DDT structure), which provides flexibility in designing networks and demonstrates that the successful use of such structures will be a perfect solution for both distribution networks and microgrid systems in providing sustainable energy to the end users.

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14

Lewandowski, Włodzimierz, and Halina Baranska. "The Influence of Selected Metals on the Aromatic System of Salicylic Acid." Applied Spectroscopy 41, no. 6 (August 1987): 976–80. http://dx.doi.org/10.1366/0003702874448003.

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Results are presented of research on the influence of Na, Mg, Cd, Al, La(III), Pb(II), Hg(I), and Hg(II) on the aromatic system of salicylic acid. Salicylic acid is regarded here as a model compound representing a wide group of aromatic ligands which are components of enzymes. The number, frequency, and relative intensities of bands in the vibrational (Raman and IR) spectra and the frequencies of the π → π* bands in the electronic (UV) spectra were analyzed. The analysis showed that metal-aromatic ligand complex formation causes significant changes in the frequencies and relative intensities of the bands associated with the aromatic system in the following regions: 1640–1370, 1350–1300, 1200–1090, and 800–650 cm−1. It was concluded that Na, Hg(I and II), Pb(II), and Cd perturb the aromatic system of salicylic acid, whereas La(III) and Al stabilize it.

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15

Dı́az, Eduardo, Abel Ferrández, Marı́a A. Prieto, and José L. Garcı́a. "Biodegradation of Aromatic Compounds byEscherichia coli." Microbiology and Molecular Biology Reviews 65, no. 4 (December 1, 2001): 523–69. http://dx.doi.org/10.1128/mmbr.65.4.523-569.2001.

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SUMMARY Although Escherichia coli has long been recognized as the best-understood living organism, little was known about its abilities to use aromatic compounds as sole carbon and energy sources. This review gives an extensive overview of the current knowledge of the catabolism of aromatic compounds by E. coli. After giving a general overview of the aromatic compounds that E. coli strains encounter and mineralize in the different habitats that they colonize, we provide an up-to-date status report on the genes and proteins involved in the catabolism of such compounds, namely, several aromatic acids (phenylacetic acid, 3- and 4-hydroxyphenylacetic acid, phenylpropionic acid, 3-hydroxyphenylpropionic acid, and 3-hydroxycinnamic acid) and amines (phenylethylamine, tyramine, and dopamine). Other enzymatic activities acting on aromatic compounds in E. coli are also reviewed and evaluated. The review also reflects the present impact of genomic research and how the analysis of the whole E. coli genome reveals novel aromatic catabolic functions. Moreover, evolutionary considerations derived from sequence comparisons between the aromatic catabolic clusters of E. coli and homologous clusters from an increasing number of bacteria are also discussed. The recent progress in the understanding of the fundamentals that govern the degradation of aromatic compounds in E. coli makes this bacterium a very useful model system to decipher biochemical, genetic, evolutionary, and ecological aspects of the catabolism of such compounds. In the last part of the review, we discuss strategies and concepts to metabolically engineer E. coli to suit specific needs for biodegradation and biotransformation of aromatics and we provide several examples based on selected studies. Finally, conclusions derived from this review may serve as a lead for future research and applications.

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16

Gehm, Christian, Thorsten Streibel, Johannes Passig, and Ralf Zimmermann. "Determination of Relative Ionization Cross Sections for Resonance Enhanced Multiphoton Ionization of Polycyclic Aromatic Hydrocarbons." Applied Sciences 8, no. 9 (September 11, 2018): 1617. http://dx.doi.org/10.3390/app8091617.

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Resonance enhanced multiphoton ionization (REMPI) is a powerful method for the sensitive determination of polycyclic aromatic hydrocarbons (PAHs) in gaseous mixtures via mass spectrometry (MS). In REMPI, ions are produced by the absorption of at least two photons including defined electronic intermediate states. As a result—unlike other laser-based ionization techniques—spectroscopic selectivity is involved into the ionization process. Nevertheless, these wavelength-dependent ionization rates impede the quantification using REMPI. For this purpose, relative photoionization cross sections (relPICS) give an easy-to-use approach to quantify REMPI-MS measurements. Hereby, the ionization behavior of a single compound was compared to that of a reference substance of a given concentration. In this study, relPICS of selected single-core aromatics and PAHs at wavelengths of 266 nm and 248 nm were determined using two different time-of-flight mass spectrometric systems (TOFMS). For PAHs, relPICS were obtained which showed a strong dependence on the applied laser intensity. In contrast, for single-core aromatics, constant values of relPICS were determined. Deviations of relPICS between both TOFMS systems were found for small aromatics (e.g., benzene), which can be assigned to the differences in UV generation in the particular system. However, the relPICS of this study were found to be in good agreement with previous results and can be used for system-independent quantification.

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17

Dobrin, Aurora, Elena Ştefania Ivan, Ionuţ Ovidiu Jerca, Ionuț-Răzvan Bera, Roxana Ciceoi, and Alexandru Ahmad Samih. "The Accumulation of Nutrients and Contaminants in Aromatic Plants Grown in a Hydroponic System." “Agriculture for Life, Life for Agriculture” Conference Proceedings 1, no. 1 (July 1, 2018): 284–89. http://dx.doi.org/10.2478/alife-2018-0042.

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Abstract Hydroponic systems are highly appreciated today, due to their potential to protect the environment and ensure a high level of food safety. In general, aromatic plants play a very important role in the food, pharmacy, cosmetics, perfumery and aromatherapy industries, all these products being highly appreciated by consumers. Due to their importance, different hydroponic systems are put in place to grow at different levels, these aromatic plants. In the present study, is analyzed the influence of three different hydroponic systems (two vertical and one horizontal) on minerals content and nutritional quality of two varieties of Occimum basilicum and one Mentha piperita variety. In this study are presented dry matter content, ash, micro and macro elements and contaminants content of leaves are presented. The results showed that the vertical system without foil had the best results, followed by the vertical system with foil comparative to the horizontal system that had the lowest content in nutritious principles. The vertical eco-sustainable systems proved to be a promising innovation for growing aromatic plants at the household level and a promising start for the intensive growing.

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18

Douglas, J. Fielding, Richard H. Mckee, Stuart Z. Cagen, Susan L. Schmitt, Patrick W. Beatty, Mark S. Swanson, Ceinwen A. Schreiner, Charles E. Ulrich, and Beverly Y. Cockrell. "A Neurotoxicity Assessment of High Flash Aromatic Naphtha." Toxicology and Industrial Health 9, no. 6 (November 1993): 1047–58. http://dx.doi.org/10.1177/074823379300900605.

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Catalytic reforming is a refining process that converts naphthenes to aromatics by dehydrogenation to make higher octane gasoline blending components. A portion of this wide-boiling range hydrocarbon stream can be separated by distillation and used for other purposes. One such application is a mixture of predominantly 9-carbon aromatic molecules (C9 Aromatics, primarily isomers of ethyltoluene and trimethylbenzene), which is removed and used as a solvent also known as High Flash Aromatic Naphtha (HFAN). A program was initiated to assess the toxicological properties of HFAN since there may be human exposure, especially in the workplace. The current study was conducted to assess the potential for neurotoxicity in the rat. Adult male Sprague-Dawley rats of approximately 300 grams body weight, in groups of twenty, were exposed by inhalation to HFAN for 90 days at concentrations of 0, 100, 500, and 1500 ppm. During this period the animals were tested monthly for motor activity and in afunctional observation battery. After three months of exposure, for 6 hours/day, 5 days/week, 10 animals/group/sex were sacrificed and selected nervous system tissue was examined histopathologically. No signs of neurotoxicity were seen in any of the evaluated parameters, nor was there evidence of pathologic changes in any of the examined tissues.

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19

Dong, Shilong, Xiaoyan Sun, Lili Wang, Yanjing Li, Wenying Zhao, Li Xia, and Shuguang Xiang. "Prediction, Application, and Mechanism Exploration of Liquid–Liquid Equilibrium Data in the Extraction of Aromatics Using Sulfolane." Processes 11, no. 4 (April 16, 2023): 1228. http://dx.doi.org/10.3390/pr11041228.

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Liquid–liquid equilibrium (LLE) data are critical for the design and optimization of processes for extracting aromatics. Partial LLE data for the non-aromatic–aromatic–sulfolane ternary system were acquired at 313.15 K and 101.3 kPa. The LLE data for the extraction of aromatics using sulfolane were predicted using the COSMO-RS model. Correspondingly, the predicted and experimental data were analyzed using the root mean square deviation (RMSD), distribution coefficient (D), and separation factor (S). The COSMO-RS model could better predict the LLE data for the extraction of aromatics by sulfolane. The results of quantum chemical calculation show that hydrogen bonds and van der Waals interactions between sulfolane–benzene and sulfolane–toluene were responsible for the strong selectivity of sulfolane for benzene and toluene over alkanes. The LLE data predicted by the COSMO-RS method using the UNIQUAC thermodynamic model were subjected to correlation analysis. The calculated RMSD values were all less than 0.0180, and the relative deviation (δ) between the simulated value of the main process index for the extraction column and the actual data was less than 2.5%, indicating that the obtained binary interaction parameters can be reliably used in designing and optimizing the extraction of aromatics using sulfolane.

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Kapustin, Rostislav, Iosif Grinvald, Andrey Vorotyntsev, Anton Petukhov, Vladimir Vorotyntsev, Sergey Suvorov, and Alexandra Baryscheva. "Formation of intermediate gas-liquid system in aromatics’ thin layers." Journal of the Serbian Chemical Society, no. 00 (2022): 87. http://dx.doi.org/10.2298/jsc211003087k.

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The present work discusses the IR spectroscopic experiments and quantum-chemical DFT study of structure and intermolecular binding in the intermediate gas-liquid systems of aromatics, namely, benzene, furane, pyridine and thiophene. These systems can be generated in thin layers near a solid surface by two different methods, depending on the physical properties of the sample. The first method includes evaporation with a subsequent compression of a sample in a variable thickness optical cell is applied to volatile components: benzene, furane, thiophene. For benzene and pyridine, the second method is used, which involves a heating-initiated evaporation into a closed inter-window space with an after-cooling of a sample. It was shown that the formed layer is not an adsorbate or a condensate. The IR data obtained by these two methods allow to conclude that the revealed systems of the considered aromatics manifest dual gas-liquid spectral properties which can pass into each other in case of varying external conditions. According to the DFT calculation results, the spatial arrangement in the aromatic thin layers can be described as a combination of ?- and ?- bonded clusters, which simulate the gas and the liquid phase state properties.

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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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Sekiguchi, Akira, Tsukasa Matsuo, and Hidetoshi Watanabe. "Cyclobutadiene Dianion Dilithium: a New Aromatic Ring System." Phosphorus, Sulfur, and Silicon and the Related Elements 168, no. 1 (January 1, 2001): 51–58. http://dx.doi.org/10.1080/10426500108546530.

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23

Abdullah, A. H., A. H. Adom, A. Y. Md Shakaff, M. N. Ahmad, A. Zakaria, N. A. Fikri, and O. Omar. "An Electronic Nose System for Aromatic Rice Classification." Sensor Letters 9, no. 2 (April 1, 2011): 850–55. http://dx.doi.org/10.1166/sl.2011.1629.

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24

Adams, Harry, Christopher A. Hunter, Kevin R. Lawson, Julie Perkins, Sharon E. Spey, Christopher J. Urch, and John M. Sanderson. "A Supramolecular System for Quantifying Aromatic Stacking Interactions." Chemistry - A European Journal 7, no. 22 (November 19, 2001): 4863–77. http://dx.doi.org/10.1002/1521-3765(20011119)7:22<4863::aid-chem4863>3.0.co;2-3.

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25

Kornau, Kathryn M., Mark A. Rickard, Nathan A. Mathew, Andrei V. Pakoulev, and John C. Wright. "Multiresonant Coherent Multidimensional Vibrational Spectroscopy of Aromatic Systems: Pyridine, a Model System." Journal of Physical Chemistry A 115, no. 16 (April 28, 2011): 4054–62. http://dx.doi.org/10.1021/jp1104856.

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26

Wang, Congcong, Wei Wang, Jian Wang, Peiping Zhang, Shiding Miao, Bo Jin, and Lina Li. "Effective removal of aromatic pollutants via adsorption and photocatalysis of porous organic frameworks." RSC Advances 10, no. 53 (2020): 32016–19. http://dx.doi.org/10.1039/d0ra05724j.

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Yoo, Byung-Woo, Duck-Il Kim, Hyung-Min Kim, and Sung-Ho Kang. "Efficient and Selective Reduction of Aromatic Nitro Compounds to Aromatic Amines by NbCl5/Indium System." Bulletin of the Korean Chemical Society 33, no. 9 (September 20, 2012): 2851–52. http://dx.doi.org/10.5012/bkcs.2012.33.9.2851.

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28

Valdes, H., K. Pluhackova, and P. Hobza. "Phenylalanyl-Glycyl-Phenylalanine Tripeptide: A Model System for Aromatic−Aromatic Side Chain Interactions in Proteins." Journal of Chemical Theory and Computation 5, no. 9 (July 28, 2009): 2248–56. http://dx.doi.org/10.1021/ct900174f.

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29

León, I., P. F. Arnáiz, I. Usabiaga, and J. A. Fernández. "Mass resolved IR spectroscopy of aniline–water aggregates." Physical Chemistry Chemical Physics 18, no. 39 (2016): 27336–41. http://dx.doi.org/10.1039/c6cp04373a.

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30

Abplanalp, Matthew J., Robert Frigge, and Ralf I. Kaiser. "Low-temperature synthesis of polycyclic aromatic hydrocarbons in Titan’s surface ices and on airless bodies." Science Advances 5, no. 10 (October 2019): eaaw5841. http://dx.doi.org/10.1126/sciadv.aaw5841.

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Titan’s equatorial dunes represent the most monumental surface structures in our Solar System, but the chemical composition of their dark organics remains a fundamental, unsolved enigma, with solid acetylene detected near the dunes implicated as a key feedstock. Here, we reveal in laboratory simulation experiments that aromatics such as benzene, naphthalene, and phenanthrene—prospective building blocks of the organic dune material—can be efficiently synthesized via galactic cosmic ray exposure of low-temperature acetylene ices on Titan’s surface, hence challenging conventional wisdom that aromatic hydrocarbons are formed solely in Titan’s atmosphere. These processes are also of critical importance in unraveling the origin and chemical composition of the dark surfaces of airless bodies in the outer Solar System, where hydrocarbon precipitation from the atmosphere cannot occur. This finding notably advances our understanding of the distribution of carbon throughout our Solar System such as on Kuiper belt objects like Makemake.

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Juliana Carla Santos da Silva, Lilian Lefol Nani Guarieiro, and Valéria Loureiro da Silva. "Study of Measurement Systems for Determination of Polycyclic Aromatic Hydrocarbons in Vehicle Environmental Samples." JOURNAL OF BIOENGINEERING, TECHNOLOGIES AND HEALTH 5, no. 1 (May 2, 2022): 91–95. http://dx.doi.org/10.34178/jbth.v5i1.203.

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Polycyclic aromatic hydrocarbons (PAHs) are organic compounds with two or more aromatic rings. Their emission sources are anthropogenic, such as burning fossil fuels in vehicles. Due to their properties, these compounds are toxic in nature and have potential carcinogens, requiring attention to their detection in the environment. Several studies have already been conducted for construction-detection systems, nevertheless, the methods are expensive and complex. The objective of this work was to identify these measurement possibilities already used to propose a new, simpler, and cheaper system for determining PAHs. So, we carried out a literature review survey to build the necessary theoretical foundation for the proposed system development.

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32

Veljković, Dušan Ž. "Strong C H/O interactions between polycyclic aromatic hydrocarbons and water: Influence of aromatic system size." Journal of Molecular Graphics and Modelling 80 (March 2018): 121–25. http://dx.doi.org/10.1016/j.jmgm.2017.12.014.

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Tasior, Mariusz, Maciej Chotkowski, and Daniel T. Gryko. "Extension of Pyrrolopyrrole π-System: Approach to Constructing Hexacyclic Nitrogen-Containing Aromatic Systems." Organic Letters 17, no. 24 (December 4, 2015): 6106–9. http://dx.doi.org/10.1021/acs.orglett.5b03129.

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Dong, Kun, Siyuan Song, Xiaocun Sun, Songyu Wu, Tingmei Li, and Hai-Liang Zhu. "Effects of landscape on the distributions of nutrients and polycyclic aromatic hydrocarbons in an urban river system." SDRP Journal of Earth Sciences & Environmental Studies 4, no. 2 (2019): 541–49. http://dx.doi.org/10.25177/jeses.4.2.ra.451.

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35

Abe, Keiichi, Masaharu Umeda, and Tokihiro Umemura. "Degradation Behavior of Silicone Fluid/Aromatic Polyamide Insulation System." IEEJ Transactions on Fundamentals and Materials 116, no. 7 (1996): 635–40. http://dx.doi.org/10.1541/ieejfms1990.116.7_635.

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Peng, Fei, Bingjie Zheng, Yao Zhang, Aroosha Faheem, Yanyan Chai, Tao Jiang, Xuguang Chen, and Yonggang Hu. "Biocatalytic Oxidation of Aromatic Compounds by Spore-Based System." ACS Sustainable Chemistry & Engineering 8, no. 37 (August 11, 2020): 14159–65. http://dx.doi.org/10.1021/acssuschemeng.0c04884.

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Zhao, Lizeng, Zhenzhong Lu, Xiulan Zhang, Dongxiang Zhang, Baohua Feng, Yuxin Nie, Duoyuan Wang, Lingzhi Hu, and Huizhu He. "Multiple hole burning in zinc-tetrabenzoporphyrin/aromatic cyanide system." Optics Communications 111, no. 1-2 (September 1994): 123–26. http://dx.doi.org/10.1016/0030-4018(94)90150-3.

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Islam, F. R., K. Prakash, K. A. Mamun, A. Lallu, and H. R. Pota. "Aromatic Network: A Novel Structure for Power Distribution System." IEEE Access 5 (2017): 25236–57. http://dx.doi.org/10.1109/access.2017.2767037.

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TAKEDA, Ryuji, Yoshimasa IKUMA, Sadayoshi MATSUMOTO, Sadao KOMEMUSHI, and Akiyoshi SAWABE. "Polycyclic Aromatic Hydrocarbons for the Soil-plant-Environment System." Journal of Agricultural Meteorology 60, no. 6 (2005): 1137–40. http://dx.doi.org/10.2480/agrmet.1137.

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PEESAPATI, V., and L. NAGARAPU. "ChemInform Abstract: Novel Aromatic System, 2,3-Diacetoxybenzocyclohepten-5-one." ChemInform 26, no. 11 (August 18, 2010): no. http://dx.doi.org/10.1002/chin.199511121.

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Mauksch, Michael, Valentin Gogonea, Haijun Jiao, and Paul von Ragué Schleyer. "Monocyclic (CH)9+—A Heilbronner Möbius Aromatic System Revealed." Angewandte Chemie International Edition 37, no. 17 (September 18, 1998): 2395–97. http://dx.doi.org/10.1002/(sici)1521-3773(19980918)37:17<2395::aid-anie2395>3.0.co;2-w.

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Zhao, Meng-Yun, Yue-Feng Tang, and Guo-Zhi Han. "Recent Advances in the Synthesis of Aromatic Azo Compounds." Molecules 28, no. 18 (September 21, 2023): 6741. http://dx.doi.org/10.3390/molecules28186741.

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Aromatic azo compounds have -N=N- double bonds as well as a larger π electron conjugation system, which endows aromatic azo compounds with wide applications in the fields of functional materials. The properties of aromatic azo compounds are closely related to the substituents on their aromatic rings. However, traditional synthesis methods, such as the coupling of diazo salts, have a significant limitation with respect to the structural design of aromatic azo compounds. Therefore, many scientists have devoted their efforts to developing new synthetic methods. Moreover, recent advances in the synthesis of aromatic azo compounds have led to improvements in the design and preparation of light-response materials at the molecular level. This review summarizes the important synthetic progress of aromatic azo compounds in recent years, with an emphasis on the pioneering contribution of functional nanomaterials to the field.

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Sels, Annelies, Giovanni Salassa, Fabrice Cousin, Lay-Theng Lee, and Thomas Bürgi. "Covalently bonded multimers of Au25(SBut)18 as a conjugated system." Nanoscale 10, no. 26 (2018): 12754–62. http://dx.doi.org/10.1039/c8nr01902a.

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Jiang, Yihui, Chunlan Wang, Nana Ma, Jie Chen, Chuanfei Liu, Fang Wang, Jiakun Xu, and Zhiqi Cong. "Regioselective aromatic O-demethylation with an artificial P450BM3 peroxygenase system." Catalysis Science & Technology 10, no. 5 (2020): 1219–23. http://dx.doi.org/10.1039/d0cy00241k.

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Highly regioselective O-demethylation of aromatic ethers related to the bioconversion of lignin was achieved by the H₂O₂-dependent engineered P450BM3 enzymes with assistance of a dual-functional small molecule (DFSM) for the first time.

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Wakahara, A., and T. Ishida. "Simple averaging procedure for aromatic ring system: mean molecular fragment of tryptophan metabolites." Acta Crystallographica Section B Structural Science 52, no. 4 (August 1, 1996): 707–12. http://dx.doi.org/10.1107/s0108768196003461.

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A simple averaging procedure of bond lengths and angles applicable to an aromatic ring system was applied to the crystal structures of the tryptophan metabolites analyzed so far, as an example. Statistical analysis showed no marked effect of the 5-substituent on the molecular dimensions of the 3-substituted indole ring in tryptophan metabolites. The standard bond lengths and angles of the 3-substituted indole ring were calculated according to the statistical averaging procedure outlined here and using data from 35 tryptophan metabolites; the interatomic correlations of the indole ring have been discussed based on these values. The result suggests the validity of the D 2 statistic for averaging the planar ring structure in aromatic systems.

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Call, Arnau, Carla Casadevall, Ferran Acuña-Parés, Alicia Casitas, and Julio Lloret-Fillol. "Dual cobalt–copper light-driven catalytic reduction of aldehydes and aromatic ketones in aqueous media." Chemical Science 8, no. 7 (2017): 4739–49. http://dx.doi.org/10.1039/c7sc01276d.

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A dual catalytic system based on earth-abundant elements reduces aromatic ketones and aldehydes to alcohols in aqueous media under visible light. An unprecedented selectivity for the reduction of aromatic ketones versus aliphatic aldehydes is reported.

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Carriel Schmitt, Caroline, Michael Rapp, Achim Voigt, and Mauro dos Santos de Carvalho. "Selective Detection of Aromatic Compounds with a Re-Designed Surface Acoustic Wave Sensor System Using a Short Packed Column." Coatings 12, no. 11 (November 2, 2022): 1666. http://dx.doi.org/10.3390/coatings12111666.

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A self-developed and newly re-designed chemical SAW sensor system composed of four polymer-coated and four differently modified nano-diamond-coated SAW sensors was applied to measure aromatic compounds in gasoline in a low-cost, fast, and easy way. An additional short packed column at the system inlet improve the selectivity for various possible fuel applications. The column allows the direct sampling of liquid fuels and pre-separates the different components in groups (aromatic and aliphatic compounds) from a fuel sample. Since the sensors employed show linearity towards concentration, an easy quantification of single fuel components was possible even within the group of aromatic compounds.

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Orozco, Felipe, Thomas Hoffmann, Mario E. Flores, Judit G. Lisoni, José Roberto Vega-Baudrit, and Ignacio Moreno-Villoslada. "Concentration Dependent Single Chain Properties of Poly(sodium 4-styrenesulfonate) Subjected to Aromatic Interactions with Chlorpheniramine Maleate Studied by Diafiltration and Synchrotron-SAXS." Polymers 13, no. 20 (October 15, 2021): 3563. http://dx.doi.org/10.3390/polym13203563.

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The polyelectrolyte poly(sodium 4-styrenesulfonate) undergoes aromatic–aromatic interaction with the drug chlorpheniramine, which acts as an aromatic counterion. In this work, we show that an increase in the concentration in the dilute and semidilute regimes of a complex polyelectrolyte/drug 2:1 produces the increasing confinement of the drug in hydrophobic domains, with implications in single chain thermodynamic behavior. Diafiltration analysis at polymer concentrations between 0.5 and 2.5 mM show an increase in the fraction of the aromatic counterion irreversibly bound to the polyelectrolyte, as well as a decrease in the electrostatic reversible interaction forces with the remaining fraction of drug molecules as the total concentration of the system increases. Synchrotron-SAXS results performed in the semidilute regimes show a fractal chain conformation pattern with a fractal dimension of 1.7, similar to uncharged polymers. Interestingly, static and fractal correlation lengths increase with increasing complex concentration, due to the increase in the amount of the confined drug. Nanoprecipitates are found in the range of 30–40 mM, and macroprecipitates are found at a higher system concentration. A model of molecular complexation between the two species is proposed as the total concentration increases, which involves ion pair formation and aggregation, producing increasingly confined aromatic counterions in hydrophobic domains, as well as a decreasing number of charged polymer segments at the hydrophobic/hydrophilic interphase. All of these features are of pivotal importance to the general knowledge of polyelectrolytes, with implications both in fundamental knowledge and potential technological applications considering aromatic-aromatic binding between aromatic polyelectrolytes and aromatic counterions, such as in the production of pharmaceutical formulations.

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Sathiyapriya, R., and R. Joel Karunakaran. "Iodination of Alkylbenzenes using Benzyltriphenylphosphonium Dichromate / I2 System." E-Journal of Chemistry 6, no. 4 (2009): 1164–66. http://dx.doi.org/10.1155/2009/928040.

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An efficient and rapid method have been found using benzyltriphenylphosphonium dichromate (PhCH2PPh3)2Cr2O7as an oxidant along with molecular iodine for the iodination of aromatic compounds. Iodination of a wide variety of alkyl benzenes were done under dichloromethane solvent system and high yields of iodo products were obtained

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Demyanyuk, O., O. Tertychna, K. Kudriashova, M. Parkhomenko, and D. Buturlym. "Use of spicy aromatic plants in vertical greening." Balanced nature using, no. 2 (April 4, 2022): 45–54. http://dx.doi.org/10.33730/2310-4678.2.2022.261248.

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The article presents the advantages of vertical greenery to create urban development and improve the ecological condition of urban areas. The possibility of using spicy-aromatic crops in vertical greenery, which is an effective way of urban farming. The classification of vertical landscaping by types of plant placement is given and it is determined that modular phytowalls are the most suitable type of vertical plant placement according to the morphological features of spicy-aromatic plants. It is noted that additional research is needed on the possibility of growing perennial aromatic plants in light and relatively inexpensive hydroponic panels — Vertical garden system technology, developed by French designer Patrick Blanc. The technology of creation and functioning of spicy-aromatic phytowalls with the help of container and modular systems of vertical landscaping such as Cascade Wall and Pixel Garden PG14 is described. Attention is focused on the importance of the correct selection of the species composition of aromatic plants to create vertical compositions. The morphological and ecological features of the most common spicy-aromatic plants of the Lamiaceae family are characterized, which are the key parameters that determine the suitability of the described plants for use in vertical greenery. To create phytowalls outside and indoors, it is recommended to use rosemary (Rosmarinus officinalis L.), plants of the genus Thymus, Salvia, Mentha, as well as Cymbopogon citratus family Poaceae, Levisticum officinale Koch family Apiaceae and others. Attention is paid to mineral nutrition and protection of spicy-aromatic plants in closed soil conditions. Improvement of vertical landscaping systems and simultaneous search for adaptation of spicy-aromatic plants to the conditions of modular cultivation are relevant research topics for the further spread of this type of landscaping in temperate climates.

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