79-98-1Relevant articles and documents
Electrochemical degradation of bisphenol A in chloride electrolyte—Factor analysis and mechanisms study
Li, Hongna,Long, Yujiao,Wang, Yu,Zhu, Changxiong,Ni, Jinren
, p. 1144 - 1152 (2017/01/06)
Electrochemical oxidation technology is a powerful method in the degradation of recalcitrant organics, due to the high oxidizing ability of active chlorine and reactive oxygen species generated in the cell. However, influencing factor analysis and intermediates detection during the electrochemical removal of organics has not been extensively studied in the chloride electrolyte. In this study, an orthogonal test array design of L16(4)3 was carried on with Pt anode in NaCl electrolyte, using the typical endocrine disruptor bisphenol A (BPA) as the model pollutant. The influencing order of the three main factors for BPA degradation rate was current density?>?initial organic concentration?>?chloride concentration, based on the analysis of variance in this experiment. This emphasized the very significance of the active chlorine and hydroxyl radicals which were closely related with the potential of the system and the applied current density. Then both organic and inorganic Cl-byproducts were determined. The concentration of chloride decreased to 9.88?mM with an initial of 10?mM in the 480-min electrolysis and extremely low concentration of active chlorine was produced in this system (maximized at 0.037?mM) for the first set. Neither chlorate nor perchlorate was detected with the Pt anode. The factor of current density influenced greatest on the formation of chloroform due to the amount of active chlorine affected by the current density. Finally, intermediates generated in the electrolysis cell were concretely investigated. Compared with traditional chlorination, the amount of chlorinated-BPA (2, 2′-D2CBPA and T4CBPA) generated was relatively less (2.46 and 10.00?μM equiv BPA), which might be due to their fast simultaneously transformation in the electrochemical system. With the isopropylidene bridge cleavage of chlorinated-BPA, one-ring aromatic compounds (2,6-dichlorophenol, 2,6-dichloro-2,5-cyclohexadiene, 2,4,6-trichlorophenol) occurred at the same time. Finally, chlorinated-BPA was totally transformed and low molecular chlorinated compounds were detected to the end of the experiment. This is one of the very few studies dealing with chlorinated organic intermediates formed in chloride electrolyte, and thus these findings may have significant technical implications for electrochemical treatment of wastewater containing BPA.
Molecular docking of bisphenol A and its nitrated and chlorinated metabolites onto human estrogen-related receptor-gamma
Babu, Sainath,Kasibotla, Agasthya V.,Uppu, Rao M.,Vellore, Nadeem A.,Dwayne, Harlan J.,Stubblefield, Michael A.
, p. 215 - 220,6 (2020/08/20)
A xenoestrogen and known endocrine disruptor, bisphenol A (BPA) binds the human estrogen-related receptor-gamma (ERRγ) with high affinity (Kd≈5.5nM). It is likely that BPA undergoes oxidative biotransformation by hypochlorite/hypochlorous acid (-OCl/HOCl) and peroxynitrite (PN) and the products formed in these reactions may serve as secondary estrogens and contribute to the toxicodynamics of BPA. Therefore, in the present study we have examined the formation of chlorinated and nitrated BPA in reactions of BPA with -OCl/HOCl and PN(+CO2) performed around the neutral pH. We have identified four major products in these reactions and they include 3-chloro-BPA (CBPA), 3,3'-dichloro-BPA (DCBPA), 3-nitro-BPA (NBPA) and 3,3'-dinitro-BPA (DNBPA). Towards understanding the toxicodynamics and estrogenic activity of BPA in biological systems, we have performed molecular docking of BPA, CBPA, DCBPA, DNBPA and NBPA onto the ERRγ using AutoDock 4.2 software and compared the binding energies with those of estradiol, the natural ligand. Based on the genetic algorithm, the three best conformations were selected and averaged for each ligand and a detailed analysis of molecular interactions based on free energies of binding (kcal/mol) was computed. The results indicate the following rank order of binding to ERRγ: BPA (-8.78±0.06)>CBPA (-8.53±0.41)>NBPA (-7.36±0.74)>DCBPA (-5.24±0.17)>DNBPA (-4.95±0.78)>estradiol (-4.94±1.04). The docking studies revealed that the OH group of one of the phenyl rings forms a hydrogen bond with Glu275/Arg316, while the OH group of other phenyl ring was bound to Asp346. These results suggest that both BPA and its putative chlorinated and nitrated metabolites have strong binding affinity compared to estradiol.
Flame retardant thermoplastic resin composition
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, (2008/06/13)
The present invention relates to a flame retardant thermoplastic resin composition that comprises a polycarbonate resin, a rubber modified graft copolymer, a styrene-containing copolymer, an oligomeric phosphoric acid ester morpholide compound as a flame retardant and a fluorinated polyolefin resin. The present invention relates to a polycarbonate thermoplastic resin composition which is superior to the resin composition using oligomeric phosphorus ester in flame retardancy, heat resistance and flexural modulus and superior to the resin composition using monophosphorus ester in the resistance for juicing, heat stability, heat resistance, flexural modulus and appearance.
