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Nansheng Deng - One of the best experts on this subject based on the ideXlab platform.
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Enhanced Photodegradation Behavior of Bisphenol F in the Presence of β-Cyclodextrin under UV Light
Environmental Engineering Science, 2007Co-Authors: Juqiang Xiao, Hong Luan, Guanghui Wang, Feng Wu, Nansheng DengAbstract:In the presence of β-cyclodextrin (β-CD), the Photodegradation behavior of bisphenol F has been studied under UV irradiation (λmax = 254 nm) in this work. The results show that the Photodegradation rate of bisphenol F (BPF) in aqueous solution with β-CD was clearly faster than that without β-CD. After 60 min of UV irradiation, the addition of β-CD increased the Photodegradation efficiency by about 40.0% for 10.0 mg L−1 bisphenol F, and the first-order rate constant increased by 3.40-fold in the presence of β-CD. The following factors were investigated as to their influence on the Photodegradation rates of bisphenol F: concentration of β-CD, pH, bisphenol F initial concentration, and organic solvent. Also, the variation of the electrical conductivity of the solution during the Photodegradation was examined. It was found that the Photodegradation of 2.50–15.0 mg L−1 bisphenol F in aqueous solution followed pseudofirst-order kinetics. This work indicates that β-CD enhanced Photodegradation under UV light has...
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UV-light induced Photodegradation of bisphenol a in water: Kinetics and influencing factors
Reaction Kinetics and Catalysis Letters, 2007Co-Authors: Beibei Wang, Peixia Li, Feng Wu, Nansheng DengAbstract:In this work, Photodegradation of bisphenol A (BPA) in water was investigated under an UV sterilization lamp (λ = 254 nm). The Photodegradation kinetics of 5.0 ~ 50.0 mg/L BPA in aqueous solutions was found to follow first-order law. The influencing factors such as the pH value, light source, different water media and salinity on Photodegradation of BPA were studied in detail.
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Photodegradation of 17α-ethynylestradiol in aqueous solution exposed to a high-pressure mercury lamp (250 W)
Environmental Pollution, 2003Co-Authors: Feng Wu, Nansheng DengAbstract:Abstract The Photodegradation of 17α-ethynylestradiol (EE2) induced by high-pressure mercury lamp (λ⩾313, 250 W) in aqueous solution of EE2 was investigated initially. The affecting factors on the Photodegradation were studied and described in details, such as EE2 initial concentration, Fe3+, algae, exposure time, and so on. The concentration of EE2 in distilled water was mainly determined using fluorescence spectrophotometer. The Photodegradation of EE2 in aqueous solution exposed to high-pressure mercury lamp was evident and could be accelerated by Fe3+ or algae (e.g. Anabaena cylindrica) in general. With the algae concentration increasing, Photodegradation rate increased. In this paper, the mechanism of photocatalytic degradation of EE2 by Fe3+ or algae is discussed primarily.
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UV-light induced Photodegradation of 17α-ethynylestradiol in aqueous solutions
Journal of Hazardous Materials, 2003Co-Authors: Feng Wu, Nansheng DengAbstract:Abstract The Photodegradation of 17α-ethynylestradiol (EE2) in aqueous solutions induced by UV-light was preliminarily studied in this paper by means of fluorescence, UV and infrared spectra. The result suggested that EE2 in aqueous solutions underwent Photodegradation under irradiation with UV disinfection lamp (λ=254 nm, 30 W), but the Photodegradation was not observed under high pressure mercury lamp (λ≥365 nm, 250 W). The Photodegradation of 1.6–20.0 mg/l EE2 in aqueous solutions at a given initial pH value of 6.8 was pseudo-first order reaction. Increasing the initial concentration of EE2 lowered the Photodegradation rate. The Photodegradation rate of EE2 reached the lowest value at pH about 5.0, higher pH values of 6.0–8.0 benefited the Photodegradation. Ferric ions can promote the Photodegradation of EE2 in aqueous solutions at pH value of 2.0–5.0.
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UV-light induced Photodegradation of 17alpha-ethynylestradiol in aqueous solutions.
Journal of hazardous materials, 2003Co-Authors: Bin Liu, Feng Wu, Nansheng DengAbstract:The Photodegradation of 17alpha-ethynylestradiol (EE2) in aqueous solutions induced by UV-light was preliminarily studied in this paper by means of fluorescence, UV and infrared spectra. The result suggested that EE2 in aqueous solutions underwent Photodegradation under irradiation with UV disinfection lamp (lambda = 254 nm, 30 W), but the Photodegradation was not observed under high pressure mercury lamp (lambda > or = 365 nm, 250 W). The Photodegradation of 1.6-20.0 mg/l EE2 in aqueous solutions at a given initial pH value of 6.8 was pseudo-first order reaction. Increasing the initial concentration of EE2 lowered the Photodegradation rate. The Photodegradation rate of EE2 reached the lowest value at pH about 5.0, higher pH values of 6.0-8.0 benefited the Photodegradation. Ferric ions can promote the Photodegradation of EE2 in aqueous solutions at pH value of 2.0-5.0.
Bin Liu - One of the best experts on this subject based on the ideXlab platform.
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UV-light induced Photodegradation of 17alpha-ethynylestradiol in aqueous solutions.
Journal of hazardous materials, 2003Co-Authors: Bin Liu, Feng Wu, Nansheng DengAbstract:The Photodegradation of 17alpha-ethynylestradiol (EE2) in aqueous solutions induced by UV-light was preliminarily studied in this paper by means of fluorescence, UV and infrared spectra. The result suggested that EE2 in aqueous solutions underwent Photodegradation under irradiation with UV disinfection lamp (lambda = 254 nm, 30 W), but the Photodegradation was not observed under high pressure mercury lamp (lambda > or = 365 nm, 250 W). The Photodegradation of 1.6-20.0 mg/l EE2 in aqueous solutions at a given initial pH value of 6.8 was pseudo-first order reaction. Increasing the initial concentration of EE2 lowered the Photodegradation rate. The Photodegradation rate of EE2 reached the lowest value at pH about 5.0, higher pH values of 6.0-8.0 benefited the Photodegradation. Ferric ions can promote the Photodegradation of EE2 in aqueous solutions at pH value of 2.0-5.0.
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UV-light induced Photodegradation of 17α-ethynylestradiol in aqueous solutions
Journal of Hazardous Materials, 2003Co-Authors: Bin Liu, Feng Wu, Nansheng DengAbstract:The Photodegradation of 17α-ethynylestradiol (EE2) in aqueous solutions induced by UV-light was preliminarily studied in this paper by means of fluorescence, UV and infrared spectra. The result suggested that EE2 in aqueous solutions underwent Photodegradation under irradiation with UV disinfection lamp (λ=254nm, 30W), but the Photodegradation was not observed under high pressure mercury lamp (λ≥365nm, 250W). The Photodegradation of 1.6-20.0mg/l EE2 in aqueous solutions at a given initial pH value of 6.8 was pseudo-first order reaction. Increasing the initial concentration of EE2 lowered the Photodegradation rate. The Photodegradation rate of EE2 reached the lowest value at pH about 5.0, higher pH values of 6.0-8.0 benefited the Photodegradation. Ferric ions can promote the Photodegradation of EE2 in aqueous solutions at pH value of 2.0-5.0. © 2003 Elsevier Science B.V. All rights reserved.
Feng Wu - One of the best experts on this subject based on the ideXlab platform.
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Microalgae-Induced Photodegradation of Bisphenol F under Simulated Sunlight
Bioinformatics and Biomedical Engineering , 2009. ICBBE 2009. 3rd International Conference on, 2009Co-Authors: Zhang'e Peng, Haizhen Yang, Feng Wu, Beibei Wang, Zhiping WangAbstract:Like BPA, bisphenol F (BPF) was used in the production of epoxy resins and polycarbonates and it was shown to be a xenoestrogen. The Photodegradation of bisphenol F (BPF) in the presence of algae was investigated under the irradiation of metal halide lamps placed in cooling trap for maintaining constant temperature by water circulation (lambdages365 nm, 250 W). The effect of algae concentration, initial pH value, concentration of humic acid and ferric ions, gas medium were investigated. The results showed that algae can enhance the Photodegradation of BPF. The Photodegradation rate of BPF increased with increasing algae concentration. Humic acid and Fe3+ ions also enhanced the Photodegradation of BPF. The effect of pH value on the BPF Photodegradation was important in the present of algae, humic acid and ferric ions. This work helps environmental scientists to understand the photochemical behavior of BPF in simulated lake water.
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Enhanced Photodegradation Behavior of Bisphenol F in the Presence of β-Cyclodextrin under UV Light
Environmental Engineering Science, 2007Co-Authors: Juqiang Xiao, Hong Luan, Guanghui Wang, Feng Wu, Nansheng DengAbstract:In the presence of β-cyclodextrin (β-CD), the Photodegradation behavior of bisphenol F has been studied under UV irradiation (λmax = 254 nm) in this work. The results show that the Photodegradation rate of bisphenol F (BPF) in aqueous solution with β-CD was clearly faster than that without β-CD. After 60 min of UV irradiation, the addition of β-CD increased the Photodegradation efficiency by about 40.0% for 10.0 mg L−1 bisphenol F, and the first-order rate constant increased by 3.40-fold in the presence of β-CD. The following factors were investigated as to their influence on the Photodegradation rates of bisphenol F: concentration of β-CD, pH, bisphenol F initial concentration, and organic solvent. Also, the variation of the electrical conductivity of the solution during the Photodegradation was examined. It was found that the Photodegradation of 2.50–15.0 mg L−1 bisphenol F in aqueous solution followed pseudofirst-order kinetics. This work indicates that β-CD enhanced Photodegradation under UV light has...
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UV-light induced Photodegradation of bisphenol a in water: Kinetics and influencing factors
Reaction Kinetics and Catalysis Letters, 2007Co-Authors: Beibei Wang, Peixia Li, Feng Wu, Nansheng DengAbstract:In this work, Photodegradation of bisphenol A (BPA) in water was investigated under an UV sterilization lamp (λ = 254 nm). The Photodegradation kinetics of 5.0 ~ 50.0 mg/L BPA in aqueous solutions was found to follow first-order law. The influencing factors such as the pH value, light source, different water media and salinity on Photodegradation of BPA were studied in detail.
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Photodegradation of 17α-ethynylestradiol in aqueous solution exposed to a high-pressure mercury lamp (250 W)
Environmental Pollution, 2003Co-Authors: Feng Wu, Nansheng DengAbstract:Abstract The Photodegradation of 17α-ethynylestradiol (EE2) induced by high-pressure mercury lamp (λ⩾313, 250 W) in aqueous solution of EE2 was investigated initially. The affecting factors on the Photodegradation were studied and described in details, such as EE2 initial concentration, Fe3+, algae, exposure time, and so on. The concentration of EE2 in distilled water was mainly determined using fluorescence spectrophotometer. The Photodegradation of EE2 in aqueous solution exposed to high-pressure mercury lamp was evident and could be accelerated by Fe3+ or algae (e.g. Anabaena cylindrica) in general. With the algae concentration increasing, Photodegradation rate increased. In this paper, the mechanism of photocatalytic degradation of EE2 by Fe3+ or algae is discussed primarily.
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UV-light induced Photodegradation of 17α-ethynylestradiol in aqueous solutions
Journal of Hazardous Materials, 2003Co-Authors: Feng Wu, Nansheng DengAbstract:Abstract The Photodegradation of 17α-ethynylestradiol (EE2) in aqueous solutions induced by UV-light was preliminarily studied in this paper by means of fluorescence, UV and infrared spectra. The result suggested that EE2 in aqueous solutions underwent Photodegradation under irradiation with UV disinfection lamp (λ=254 nm, 30 W), but the Photodegradation was not observed under high pressure mercury lamp (λ≥365 nm, 250 W). The Photodegradation of 1.6–20.0 mg/l EE2 in aqueous solutions at a given initial pH value of 6.8 was pseudo-first order reaction. Increasing the initial concentration of EE2 lowered the Photodegradation rate. The Photodegradation rate of EE2 reached the lowest value at pH about 5.0, higher pH values of 6.0–8.0 benefited the Photodegradation. Ferric ions can promote the Photodegradation of EE2 in aqueous solutions at pH value of 2.0–5.0.
Toru Takagishi - One of the best experts on this subject based on the ideXlab platform.
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Photodegradation of a disperse dye on polyester fiber and in solution
Dyes and Pigments, 1996Co-Authors: Nobuyuki Katsuda, Takashi Omura, Katsumasa Otake, Satoshi Yabushita, Toru TakagishiAbstract:The Photodegradation behavior of dyes on fibers such as nylon, cotton fibers, and in particular, polyester, and in a solution has been investigated. The undyed and dyed fibers were irradiated with monochromatic light of various wavelengths. The light source was separated into 20 distinct wavelengths and the Photodegradation behavior at each wavelength was examined. It was found that the most effective wavelength for the Photodegradation of a disperse dye on polyester fiber was near 320 nm. The wavelength also affected the Photodegradation of the fiber itself. Similar phenomena were observed for nylon fiber: light near 370 nm influenced significantly both the dye on the fiber and the fiber itself. With cotton, light at 260 nm was significant. To clarify these results, Photodegradation of the dye in ethyl acetate containing dissolved polyester was also carried out. The same phenomena as those observed on the fiber were shown to be operative.
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Photodegradation of a disperse dye on polyester fiber and in solution
Dyes and Pigments, 1996Co-Authors: Nobuyuki Katsuda, Takashi Omura, Katsumasa Otake, Satoshi Yabushita, Toru TakagishiAbstract:The Photodegradation behavior of dyes on fibers such as nylon, cotton fibers, and in particular, polyester, and in a solution has been investigated. The undyed and dyed fibers were irradiated with monochromatic light of various wavelengths. The light source was separated into 20 distinct wavelengths and the Photodegradation behavior at each wavelength was examined. It was found that the most effective wavelength for the Photodegradation of a disperse dye on polyester fiber was near 320 nm. The wavelength also affected the Photodegradation of the fiber itself. Similar phenomena were observed for nylon fiber: light near 370 nm influenced significantly both the dye on the fiber and the fiber itself. With cotton, light at 260 nm was significant. To clarify these results, Photodegradation of the dye in ethyl acetate containing dissolved polyester was also carried out. The same phenomena as those observed on the fiber were shown to be operative. Copyright © 1996 Elsevier Science Ltd.
Jingwen Chen - One of the best experts on this subject based on the ideXlab platform.
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unveiling self sensitized Photodegradation pathways by dft calculations a case of sunscreen p aminobenzoic acid
Chemosphere, 2016Co-Authors: Siyu Zhang, Jingwen Chen, Qing ZhaoAbstract:Self-sensitized Photodegradation has been observed for diverse aquatic organic pollutants. However, Photodegradation pathways have not been clarified in previous experimental studies. Here, we attempted to probe self-sensitized Photodegradation pathways of organic pollutants employing both photolytic experiments and density functional theory calculations. By performing photolytic experiments, we found that singlet state oxygen (1O2) play an essential role in Photodegradation of a sunscreen p-aminobenzoic acid (PABA). PABA can photogenerate 1O2 and react fast with 1O2. We hypothesized that PABA underwent 1O2 induced self-sensitized Photodegradation. By calculating transition states, intermediates and reaction barriers, we found that 1O2 can oxidize PABA through electrophilic attacks on the benzene ring to abstract one H atom of the amino group following a 1,3-addition mechanism or to induce decarboxylation. Either pathway produces a hydroperoxide. O-O bond cleavage of the hydroperoxides occurring at ground states or the lowest triplet excited states can produce phenoxyl radical precursors of 4-amino-3-hydroxybenzoic acid and 4-aminophenol, which are Photodegradation products detected in experiments. Thus, a viable 1O2 self-sensitized Photodegradation mechanism was unveiled for PABA.
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photochemical transformation of sunscreen agent benzophenone 3 and its metabolite in surface freshwater and seawater
Chemosphere, 2016Co-Authors: Yingjie Li, Xianliang Qiao, Chengzhi Zhou, Yanan Zhang, Zhiqiang Fu, Jingwen ChenAbstract:Abstract The occurrence of sunscreen agents and their metabolites in surface waters gives rise to public concerns. However, little is known about the environmental fate of these pollutants at present, especially for their metabolites. In this study, we investigated the photochemical of sunscreen agents and their metabolites in natural waters, adopting benzophenone-3 (BP-3) and its human metabolite 4-hydroxybenzophenone (4-OH-BP3) as examples. Results show that only anionic forms of both BP-3 and 4-OH-BP3 can undergo direct Photodegradation. The photolytic rates of both compounds in natural waters are faster as compared to those in pure water. Radical scavenging experiments revealed that triplet-excited dissolved organic matter (3DOM∗) was responsible for the indirect Photodegradation of BP-3 and 4-OH-BP3 in seawater, whereas in freshwater, the indirect Photodegradation of these two compounds was attributed to 3DOM∗ and ·OH. 1O2 plays a negligible role in their Photodegradation because of the weak 1O2 reactivity. Furthermore, we probed the contribution of ·OH and 3DOM∗ to the Photodegradation of both compounds in freshwater, and the results revealed that ·OH accounted for 56% and 59% of the observed Photodegradation for BP-3 and 4-OH-BP3, respectively, whereas 3DOM∗ accounted for 43% and 12% of the observed Photodegradation for BP-3 and 4-OH-BP3, respectively. These results are helpful in assessing the ecological risk of BP-3 and its metabolite in the aquatic environment.
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Photodegradation of fluoroquinolone antibiotic gatifloxacin in aqueous solutions
Chinese Science Bulletin, 2010Co-Authors: Linke Ge, Siyu Zhang, Jingwen Chen, Zhuang Wang, Chunling WangAbstract:Fluoroquinolone antibiotics (FQs) are frequently detected as emerging pollutants in aqueous environments. In this study, kinetics, influencing factors and mechanisms on the Photodegradation of gatifloxacin, a representative FQ, were investigated. The Photodegradation follows the pseudo-first-order kinetics. Gatifloxacin photodegrades with a quantum yield of (5.94 ± 0.95) × 10−3 in pure water and undergoes direct photolysis as well as self-sensitized Photodegradation. The FQ photodegrades slower in freshwater and seawater than in pure water, which is attributed to the integrative effects of pH and the aqueous dissolved matter (e.g., humic acids and NO3 −) on the Photodegradation. A toxicity test using Vibrio fischeri revealed the formation of hazardous photoproducts.
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effects of fe2o3 organic matter and carbonate on photocatalytic degradation of lindane in the sediment from the liao river china
Chemosphere, 2003Co-Authors: Xie Quan, Jingwen Chen, Shuo Chen, Yazhi Zhao, Fenglin YangAbstract:Fourteen sediment samples with different content of Fe 2 O 3 were collected from the lower reaches of the Liao River in China. The Photodegradation of lindane on the surfaces of these sediments was investigated to observe the effects of Fe 2 O 3 and other photoinducable substances, such as TiO 2 and organic substances, on Photodegradation of lindane. A partial least-squares (PLS) analysis model was developed to find out the statistical relationship between the Photodegradation and the contents of these photoinducable substances. It was concluded from the PLS analysis that inorganic carbon and organic carbon have negative effects, whereas Fe 2 O 3 and TiO 2 accelerate the Photodegradation of lindane in the sediment samples when 365 nm UV light was used as light source. In all cases of the experiments, the Photodegradation of lindane in the sediment samples were fitted for pseudo-first-order kinetics.
