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1

Kosaka, Koji, Takahiko Nakai, Yuta Hishida, Mari Asami, Keiko Ohkubo, and Michihiro Akiba. "Formation of 2,6-dichloro-1,4-benzoquinone from aromatic compounds after chlorination." Water Research 110 (March 2017): 48–55. http://dx.doi.org/10.1016/j.watres.2016.12.005.

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2

Reddy, G. Vijay Bhasker, Maarten D. Sollewijn Gelpke, and Michael H. Gold. "Degradation of 2,4,6-Trichlorophenol by Phanerochaete chrysosporium: Involvement of Reductive Dechlorination." Journal of Bacteriology 180, no. 19 (October 1, 1998): 5159–64. http://dx.doi.org/10.1128/jb.180.19.5159-5164.1998.

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ABSTRACT Under secondary metabolic conditions, the lignin-degrading basidiomycete Phanerochaete chrysosporium mineralizes 2,4,6-trichlorophenol. The pathway for the degradation of 2,4,6-trichlorophenol has been elucidated by the characterization of fungal metabolites and oxidation products generated by purified lignin peroxidase (LiP) and manganese peroxidase (MnP). The multistep pathway is initiated by a LiP- or MnP-catalyzed oxidative dechlorination reaction to produce 2,6-dichloro-1,4-benzoquinone. The quinone is reduced to 2,6-dichloro-1,4-dihydroxybenzene, which is reductively dechlorinated to yield 2-chloro-1,4-dihydroxybenzene. The latter is degraded further by one of two parallel pathways: it either undergoes further reductive dechlorination to yield 1,4-hydroquinone, which isortho-hydroxylated to produce 1,2,4-trihydroxybenzene, or is hydroxylated to yield 5-chloro-1,2,4-trihydroxybenzene, which is reductively dechlorinated to produce the common key metabolite 1,2,4-trihydroxybenzene. Presumably, the latter is ring cleaved with subsequent degradation to CO2. In this pathway, the chlorine at C-4 is oxidatively dechlorinated, whereas the other chlorines are removed by a reductive process in which chlorine is replaced by hydrogen. Apparently, all three chlorine atoms are removed prior to ring cleavage. To our knowledge, this is the first reported example of aromatic reductive dechlorination by a eukaryote.
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3

D'SOUZA, FRANCIS, JAMIE L. POLLOCK, EVANGELOS A. NANTSIS, and MELVIN E. ZANDLER. "Charge-transfer Interactions of Octaethylporphycenatozinc(II) with 2,6-Dichloro-3,5-dicyano-1,4-benzoquinone." Journal of Porphyrins and Phthalocyanines 01, no. 02 (April 1997): 101–7. http://dx.doi.org/10.1002/(sici)1099-1409(199704)1:2<101::aid-jpp12>3.0.co;2-f.

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Charge-transfer interactions of octaethylporphycenatozinc(II), ( OEPc ) Zn with 2,6-dichloro-3,5-dicyano-1,4-benzoquinone, DDQ, in non-aqueous solvents are reported. Both optical absorption and cyclic voltammetry studies reveal the formation of stable charge-transfer complexes between ( OEPc ) Zn and DDQ. New redox couples corresponding to reduction of the charge-transfer complex have been electrochemically detected. The formation of charge-transfer complexes between ( OEPc ) Zn and doubly reduced DDQ is examined and the present electrochemical studies reveal the possible existence of such complexes in solution. Based on semiempirical AM1 and PM3 calculations, interaction through the zinc(II) metal center of ( OEPc ) Zn and cyanide nitrogen of the quinone is proposed.
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4

Desai, T., J. Gigg, and R. Gigg. "The Allyl Group for Protection in Carbohydrate Chemistry. XXXI. Conversion of Allyl 2,6-Di-O-benzyl-α-D-galactopyranoside Into Allyl 2,6-Di-O-benzyl-α-D-glucopyranoside and 2,6-Di-O-benzyl-D-glucopyranose." Australian Journal of Chemistry 49, no. 3 (1996): 305. http://dx.doi.org/10.1071/ch9960305.

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Allyl 2,6-di-O-benzyl-α-D-galactopyranoside was converted by tin-mediated alkylation into the 3-O-p-methoxybenzyl ether which gave the 4-O-mesyl derivative. Sodium benzoate in refluxing N,N-dimethylformamide converted the last compound into allyl 4-O-benzoyl-2,6-di-O-benzyl-3-O-p-methoxybenzyl-α-D-glucopyranoside in high yield. This was saponified and the product was treated with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone to give the required allyl 2,6-di-O-benzyl-α-D-glucopyranoside whose structure was confirmed by conversion into the known 2,3,4,6-tetra-O-benzyl-D-glucopyranose. Removal of the allyl group from allyl 2,6-di-O-benzyl-α-D-glucopyranoside by a standard procedure gave 2,6-di-O-benzyl-D-glucopyranose. Both of the title compounds are required as intermediates for the synthesis of analogues of the 'adenophostins'.
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5

Gill, Melvyn, Peter M. Morgan, Jin Yu, and Jonathan M. White. "Pigments of Fungi. XLVII. Cardinalic Acid, a New Anthraquinone Carboxylic Acid from the New Zealand Toadstool Dermocybe cardinalis and the Synthesis and X-Ray Crystal Structure of Methyl 1,7,8-Tri-O-methylcardinalate." Australian Journal of Chemistry 51, no. 3 (1998): 213. http://dx.doi.org/10.1071/c97154.

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Cardinalic acid (1,7,8-trihydroxy-6-methoxy-3-methyl-9,10-dioxoanthracene-2-carboxylic acid) (4) and the known anthraquinone carboxylic acids endocrocin (1), dermolutein (2) and cinnalutein (3) have been isolated from the New Zealand toadstool Dermocybe cardinalis. Methyl 1,7,8-tri-O-methylcardinalate (5) has been prepared both by permethylation of the natural product (4) and from 2,6-dichloro-1,4-benzoquinone by two consecutive regioselective Diels–Alder cycloaddition reactions. A single-crystal X-ray structure analysis of the ester (5) corroborates the structure of the natural product (4) and confirms the outcome of both cycloaddition reactions.
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6

Chapyshev, Sergei V., and Toshikazu Ibata. "Intermediates in the Reactions of Chloranil and 2,6-Dichloro-1,4-benzoquinone with Pyrrolidine." Mendeleev Communications 4, no. 3 (January 1994): 109–10. http://dx.doi.org/10.1070/mc1994v004n03abeh000373.

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7

Qin, Feng, Yuan-Yuan Zhao, Yuli Zhao, Jessica M Boyd, Wenjun Zhou, and Xing-Fang Li. "A Toxic Disinfection By-product, 2,6-Dichloro-1,4-benzoquinone, Identified in Drinking Water." Angewandte Chemie International Edition 49, no. 4 (December 18, 2009): 790–92. http://dx.doi.org/10.1002/anie.200904934.

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8

Qin, Feng, Yuan-Yuan Zhao, Yuli Zhao, Jessica M Boyd, Wenjun Zhou, and Xing-Fang Li. "A Toxic Disinfection By-product, 2,6-Dichloro-1,4-benzoquinone, Identified in Drinking Water." Angewandte Chemie 122, no. 4 (December 18, 2009): 802–4. http://dx.doi.org/10.1002/ange.200904934.

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9

D'Souza, Francis, Jamie L. Pollock, Evangelos A. Nantsis, and Melvin E. Zandler. "Charge‐transfer Interactions of Octaethylporphycenatozinc(II) with 2,6-Dichloro-3,5-dicyano-1,4-benzoquinone." Journal of Porphyrins and Phthalocyanines 1, no. 2 (April 1997): 101–7. http://dx.doi.org/10.1002/(sici)1099-1409(199704)1:2<101::aid-jpp12>3.3.co;2-6.

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10

Ge, Fei, Yao Xiao, Yixuan Yang, Wei Wang, Birget Moe, and Xing-Fang Li. "Formation of water disinfection byproduct 2,6-dichloro-1,4-benzoquinone from chlorination of green algae." Journal of Environmental Sciences 63 (January 2018): 1–8. http://dx.doi.org/10.1016/j.jes.2017.10.001.

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11

Al-Wasidi, Asma S., Nawal M. Al-Jafshar, Amal M. Al-Anazi, Eid H. Alosaimi, Moamen S. Refat, Lamia El-Zayat, Mohamed A. Al-Omar, Ahmed M. Naglah, and K. M. Abou El-Nour. "Electron-transfer complexation of morpholine donor molecule with some π – acceptors: Synthesis and spectroscopic characterizations." Polish Journal of Chemical Technology 21, no. 4 (December 1, 2019): 82–88. http://dx.doi.org/10.2478/pjct-2019-0043.

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Abstract Morpholine is an interesting moiety that used widely in several organic syntheses. The intermolecular charge-transfer (CT) complexity associated between morpholine (Morp) donor with (monoiodobromide “IBr”, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone “DDQ”, 2,6-dichloroquinone-4-chloroimide “DCQ” and 2,6-dibromoquinone-4-chloroimide “DBQ”) π–acceptors have been spectrophotometrically investigated in CHCl3 and/or MeOH solvents. The structures of the intermolecular charge-transfer (CT) were elucidated by spectroscopic methods like, infrared spectroscopy. Also, different analyses techniques such as UV-Vis and elemental analyses were performed to characterize the four morpholine [(Morp)(IBr)], [(Morp)(DDQ)], [(Morp)(DCQ)] and [(Morp)(DBQ)] CT-complexes which reveals that the stoichiometry of the reactions is 1:1. The modified Benesi-Hildebrand equation was utilized to determine the physical spectroscopic parameters such as association constant (K) and the molar extinction coefficient (ε).
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12

Colter, Allan K., Charles C. Lai, A. Gregg Parsons, N. Bruce Ramsey, and Gunzi Saito. "Kinetics and mechanism of oxidation of N,N′-dimethyl-9,9′-biacridanyl by some π acceptors and a one-electron oxidant." Canadian Journal of Chemistry 63, no. 2 (February 1, 1985): 445–51. http://dx.doi.org/10.1139/v85-073.

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Oxidation of N,N′-dimethyl-9,9′-biacridanyl (DD) has been investigated as a model for single electron transfer (SET)-initiated oxidation of NADH coenzyme models such as N-methylacridan (DH). Oxidants investigated cover a 1010-fold range of reactivity in acetonitrile and include the π acceptors 1,4-benzoquinone (BQ), 2,6-dichloro-1,4-benzoquinone (DCIBQ), p-chloranil (CA), 2,3-dicyanobenzoquinone (DCBQ), 2,3-dicyano-1,4-naphthoquinone (DCNQ), 2,3-dicyano-5-nitro-1,4-naphthoquinone (DCNNQ), 9-dicyanomethylene-2,4,7-trinitrofluorene (DCMTNF), 9-dicyanomethylene-2,4,5,7-tetranitrofluorene (DCMTENF), 7,7,8,8-tetracyanoquinodimethane (TCNQ), and tetracyanoethylene (TCNE), and the one-electron oxidant tris(2,2′-bipyridyl)cobalt(III), [Formula: see text] The oxidation product is, in every case, N-methylacridinium ion (D+). A mechanism involving a rate-determining electron transfer with simultaneous fragmentation to D+ and N-methyl-9-acridanyl radical (D•) is proposed. This mechanism is supported by the observed dependence of the rate on oxidant reduction potential, by spin-trapping experiments, by kinetic isotope effects in oxidation of 9,9′-dideuterio-DD, and by substituent effects in oxidation of 2,2′- and 3,3′-dimethoxy-DD. The rate of oxidation of DD relative to that of DH is 3.4 × 102 with [Formula: see text] and with the π acceptors varies from ea. 0.3 (BQ) to 8.1 × 104 (DCMTENF). The results rule out a SET-initiated mechanism for oxidation of DH by all of the oxidants studied except TCNQ and DCMTENF.
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13

Hassanein, Mahmoud T., Shady S. Gerges, Mohamed A. Abdo, and Sahar H. El-Khalafy. "Studies on the oxidation of 2,6-di-tert-butylphenol by molecular oxygen catalyzed by cobalt(II) tetraarylporphyrins bound to cationic latex." Journal of Porphyrins and Phthalocyanines 09, no. 09 (September 2005): 621–25. http://dx.doi.org/10.1142/s1088424605000721.

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A cationic latex has been prepared by emulsion copolymerization of styrene and divinylbenzene with 2 mol.% of quaternary ammonium ion surfactant monomer. The catalytic activity of cobalt(II) sulfonated tetraarylporphrins 1-5 supported on the cationic latex 6 was investigated in the autoxidation of 2,6-di-tert-butylphenol in water. All colloidal catalysts showed good catalytic activity in the autoxidation of 2,6-di-tert-butylphenol. Reaction products were identified as 2,6-di-tert-butyl-1,4-benzoquinone and the oxidative coupling product as 3,3',5,5'-tetra-tert-butyl-4,4'-diphenoquinone. The rate of autoxidation reaction catalyzed by 5 supported on cationic latex was found to increase with increasing pH in the range 7.0-10.0. At constant concentration of cobalt(II) porphyrin 5 in the reaction mixture, the rate as a function of the weight of the latex showed a maximum. The rate of autoxidation increased with increasing partial pressure of dioxygen in the range between 0.2 and 1.0 atm. 5,10,15,20-tetrakis(2,4,6-trimethyl-3,5-disulfonatopheny)porphyrinatocobalt(II) bound to the cationic latex was found to be the most reactive catalyst and the latex supported 5,10,15,20-tetrakis(2,6-dichloro-3-sulfonatophenyl)porphyrinatocobalt(II) showed the highest stability.
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14

Mohan, Aarthi, and David A. Reckhow. "Hydrolysis and Chlorination of 2,6-Dichloro-1,4-benzoquinone under conditions typical of drinking water distribution systems." Water Research 200 (July 2021): 117219. http://dx.doi.org/10.1016/j.watres.2021.117219.

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15

NAKAI, Takahiko, Koji KOSAKA, Mari ASAMI, and Michihiro AKIBA. "Analysis and Occurrence of 2,6-Dichloro-1,4-benzoquinone in Drinking Water by Liquid Chromatography-Tandem Mass Spectrometry." Journal of Japan Society on Water Environment 38, no. 3 (2015): 67–73. http://dx.doi.org/10.2965/jswe.38.67.

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16

Pei, Jiying, Ruiling Zhang, Chengchih Hsu, and Yinghui Wang. "Mass Spectrometry-Inspired Degradation of Disinfection By-Product, 2,6-Dichloro-1,4-benzoquinone, in Drinking Water by Heating." Mass Spectrometry 7, no. 1 (June 29, 2018): A0068. http://dx.doi.org/10.5702/massspectrometry.a0068.

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17

Fábián, István, and Gábor Lente. "Light-induced multistep redox reactions: The diode-array spectrophotometer as a photoreactor." Pure and Applied Chemistry 82, no. 10 (June 23, 2010): 1957–73. http://dx.doi.org/10.1351/pac-con-09-11-16.

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The light source of a photometer may induce chemical reactions in photosensitive reactive systems. Diode-array spectrophotometers are particularly suitable for producing such phenomena. This paper provides an overview on how this equipment can be used as a photoreactor. The principles of various techniques to control the intensity and spectral region of the illuminating light are discussed in detail. It will be shown that the quantum yields of various photochemically induced redox reactions can be determined by exploiting specific features of diode-array spectrophotometers. Kinetic coupling between primary photo-chemical and secondary thermally activated reaction steps are utilized to explore intimate details of composite redox reactions. Key aspects of the method applied are demonstrated via the photoreactions of 2,6-dichloro-1,4-benzoquinone (DCQ), the photoinduced autoxidation of S(IV) and a photochemically activated redox reaction of the chlorate ion.
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18

Abdou, Wafaa M., Monier A. I. Salem, and Ashraf A. Sediek. "Comparative Behaviour of 2,6-Di-tert-butyl- and 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone with Some Phosphorus Reagents." Journal of Chemical Research, no. 1 (1998): 28–29. http://dx.doi.org/10.1039/a704394e.

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19

Hung, Stephanie, Aarthi Mohan, David A. Reckhow, and Krystal J. Godri Pollitt. "Assessment of the in vitro toxicity of the disinfection byproduct 2,6-dichloro-1,4-benzoquinone and its transformed derivatives." Chemosphere 234 (November 2019): 902–8. http://dx.doi.org/10.1016/j.chemosphere.2019.06.086.

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20

Zuo, Yu-Ting, Yu Hu, Wei-Wei Lu, Jing-Jing Cao, Fan Wang, Xue Han, Wen-Qing Lu, and Ai-Lin Liu. "Toxicity of 2,6-dichloro-1,4-benzoquinone and five regulated drinking water disinfection by-products for the Caenorhabditis elegans nematode." Journal of Hazardous Materials 321 (January 2017): 456–63. http://dx.doi.org/10.1016/j.jhazmat.2016.09.038.

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21

ABDOU, W. M., M. A. I. SALEM, and A. A. SEDIEK. "ChemInform Abstract: Comparative Behavior of 2,6-Di-tert-butyl- and 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone with Some Phosphorus Reagents." ChemInform 30, no. 10 (June 17, 2010): no. http://dx.doi.org/10.1002/chin.199910172.

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22

Choi, Donghoon, Eun Ju Lee, Kyeong-Ah Kim, Soo Young Park, and Nakjoong Kim. "Photoconductivity and photovoltaic effect of charge-transfer complex of poly[4-phenyl-2,6-(p-phenoxy) quinoline] and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone." Journal of Applied Polymer Science 50, no. 8 (November 20, 1993): 1429–33. http://dx.doi.org/10.1002/app.1993.070500814.

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23

Baminger, Ursula, Sai S. Subramaniam, V. Renganathan, and Dietmar Haltrich. "Purification and Characterization of Cellobiose Dehydrogenase from the Plant Pathogen Sclerotium(Athelia) rolfsii." Applied and Environmental Microbiology 67, no. 4 (April 1, 2001): 1766–74. http://dx.doi.org/10.1128/aem.67.4.1766-1774.2001.

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ABSTRACT Cellobiose dehydrogenase (CDH) is an extracellular hemoflavoenzyme produced by several wood-degrading fungi. In the presence of a suitable electron acceptor, e.g., 2,6-dichloro-indophenol (DCIP), cytochromec, or metal ions, CDH oxidizes cellobiose to cellobionolactone. The phytopathogenic fungus Sclerotium rolfsii (teleomorph: Athelia rolfsii) strain CBS 191.62 produces remarkably high levels of CDH activity when grown on a cellulose-containing medium. Of the 7,500 U of extracellular enzyme activity formed per liter, less than 10% can be attributed to the proteolytic product cellobiose:quinone oxidoreductase. As with CDH from wood-rotting fungi, the intact, monomeric enzyme from S. rolfsii contains one heme b and one flavin adenine dinucleotide cofactor per molecule. It has a molecular size of 101 kDa, of which 15% is glycosylation, and a pI value of 4.2. The preferred substrates are cellobiose and cellooligosaccharides; additionally, β-lactose, thiocellobiose, and xylobiose are efficiently oxidized. Cytochrome c (equine) and the azino-di-(3-ethyl-benzthiazolin-6-sulfonic acid) cation radical were the best electron acceptors, while DCIP, 1,4-benzoquinone, phenothiazine dyes such as methylene blue, phenoxazine dyes such as Meldola's blue, and ferricyanide were also excellent acceptors. In addition, electrons can be transferred to oxygen. Limited in vitro proteolysis with papain resulted in the formation of several protein fragments that are active with DCIP but not with cytochrome c. Such a flavin-containing fragment, with a mass of 75 kDa and a pI of 5.1 and lacking the heme domain, was isolated and partially characterized.
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24

Li, Yuna, Lifen Zhang, Lumin Yang, Ying Zhang, and Zhiguang Niu. "Hydrolysis characteristics and risk assessment of a widely detected emerging drinking water disinfection-by-product—2,6-dichloro-1,4-benzoquinone—in the water environment of Tianjin (China)." Science of The Total Environment 765 (April 2021): 144394. http://dx.doi.org/10.1016/j.scitotenv.2020.144394.

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25

Pan, Zhangbin, Xiaokang Zhu, Guifang Li, Yongqiang Wang, Mei Li, Shaohua Sun, Ruibao Jia, and Li'an Hou. "Degradation of 2,6-dichloro-1,4-benzoquinone by advanced oxidation with UV, H2O2, and O3: parameter optimization and model building." Journal of Water Supply: Research and Technology-Aqua, August 2, 2021. http://dx.doi.org/10.2166/aqua.2021.026.

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Abstract Halobenzoquinones are disinfection by-products with cytotoxicity, carcinogenicity, and genotoxicity. In this study, we investigated the removal of the HBQ 2,6-dichloro-1,4-benzoquinone (DCBQ) from water using advanced oxidation processes. The removal of DCBQ from water using UV, H2O2, and O3 advanced oxidation processes individually was not ideal with removal rates of 36.1% with a UV dose of 180 mJ/cm2, 32.0% with 2 mg/L H2O2, and 57.9% with 2 mg/L O3. Next, we investigated using the combined UV/H2O2/O3 advanced oxidation process to treat water containing DCBQ. A Box–Behnken design was used to optimize the parameters of the UV/H2O2/O3 process, which gave the following optimum DCBQ removal conditions: UV dose of 180 mJ/cm2, O3 concentration of 0.51 mg/L, and H2O2 concentration of 1.76 mg/L. The DCBQ removal rate under the optimum conditions was 94.3%. We also found that lower humic acid concentrations promoted DCBQ degradation, while higher humic acid concentrations inhibited DCBQ degradation.
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26

Aguiar, Allan Carlos S., William B. Veloso, Iranaldo S. da Silva, Auro A. Tanaka, and Luiza Maria F. Dantas. "Voltammetric and spectrophotometric studies of toxic disinfection by-product 2,6-dichloro-1,4-benzoquinone and its behavior with DNA." Chemical Papers, September 25, 2021. http://dx.doi.org/10.1007/s11696-021-01880-9.

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