Time filter

Source Type

Xie Y.,Northeastern University China | Pan Y.,Sinosteel Anshan Research Institute of Thermo energy Co. | Bai B.,Northeastern University China | Xu Z.,Northeastern University China | And 4 more authors.
Journal of Computational and Theoretical Nanoscience

Two bacteria as Pseudomonas Putida and Citrobacter Freundii were selected to degrading nonyphenol (NP). The degradation performance and the optimal parameters were investigated. The results showed that the optimal parameters were culture temperature of 30 C, initial culture medium pH of 6~7, initial NP dosage of 5 μg/mL, initial bacteria dosage of 2% (V/V) and co-metabolic substrate of 2.0 mg/mL peptone. Under the optimal parameters, the highest degradation efficiencies were 49% and 50% for Pseudomonas Putida and Citrobacter Freundii, respectively. The degradation mainly occurred in the first 36 hrs. The mixture of two bacteria presented mutual promotion effect in degrading NP. The optimal ratio of Pseudomonas Putida to Citrobacter Freundii, was 3:2 and the highest NP degradation efficiency achieved about 53%. © 2015 American Scientific Publishers All rights reserved. Source

Li X.,CAS Research Center for Eco Environmental Sciences | Li Y.,CAS Research Center for Eco Environmental Sciences | Zhang Q.,CAS Research Center for Eco Environmental Sciences | Wang P.,CAS Research Center for Eco Environmental Sciences | And 3 more authors.

The concern about emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) from steel industrial parks has increased in the past decades. In this study, polyurethane foam (PUF)-disk based passive air samples were collected in and around a big steel industrial park of Anshan, Northeast China from June 2008 to March 2009. The levels, seasonal variations and potential sources of PCDD/Fs, PCBs and PBDEs in the atmosphere around the steel industrial complex were investigated, and potential contribution of these three groups of persistent organic pollutants (POPs) from iron and steel production was also assessed. The air concentrations of ∑17PCDD/Fs (summer: 0.02-2.77pgm-3; winter: 0.20-9.79pgm-3), ∑19PCBs (summer: 23.5-155.8pgm-3; winter: 14.6-81.3pgm-3) and ∑13PBDEs (summer: 2.91-10.7pgm-3; winter: 1.10-3.89pgm-3) in this targeted industrial park were relatively low in comparison to other studies, which implied that the industrial activities of iron and steel had not resulted in serious contamination to the ambient air in this area. On the whole, the air concentrations of PCDD/Fs in winter were higher than those of summer, whereas the concentrations of PCBs and PBDEs showed opposite trends. The result from principal component analysis indicated that coal combustion might be the main contributor of PCDD/F sources in this area. © 2011 Elsevier Ltd. Source

Li Y.,CAS Research Center for Eco Environmental Sciences | Wang P.,CAS Research Center for Eco Environmental Sciences | Ding L.,CAS Research Center for Eco Environmental Sciences | Li X.,CAS Research Center for Eco Environmental Sciences | And 5 more authors.

Air monitoring of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) was carried out in June 2008 and January 2009 to investigate the concentrations, profiles and estimating potential inhalation risks to the local residents around a steel plant area in northeast China. The air concentrations and WHO-TEQs of PCDD/Fs ranged 94-4944 fg m-3 (average 1352 fg m-3) and 3-247 fg m-3 (average 81 fg m-3), respectively. The WHO-TEQ concentrations of dioxin-like PCBs ranged 1-18 fg m-3 (average 5 fg m-3), contributing to 3.6-26% of the total TEQ. Higher PCDD/F concentrations were observed in the winter, whereas higher dioxin-like PCB concentrations were found in the summer. The seasonal trend can be related to the significant correlation between the concentrations of dioxins and the reciprocal of temperature (positive for PCDD/Fs, P < 0.01; negative for dioxin-like PCBs, P = 0.05). A significant positive correlation (P < 0.0001) was found between the concentration of total suspended particulate (TSP) and PCDD/F concentrations, but not for PCB congeners. Although the steel plant sites showed higher dioxin levels than the residential and background areas, the PCDD/F levels in the atmosphere of the steel plant area was at a relatively low level. The results from this study provides further aid in evaluating the impact of steel plants as PCDD/Fs emission sources to the ambient air in China. Crown Copyright © 2010. Source

Xie Y.,Northeastern University China | Li X.,Northeastern University China | Chai T.,Northeastern University China | Ren J.,Northeastern University China | And 4 more authors.
Desalination and Water Treatment

Abstract: A metal membrane and a polyethersulfone (PES) membrane were compared in this study. The surface morphology, inherent resistance, and critical flux of the membranes were first investigated. The two membranes were then placed in an activated sludge reactor to treat municipal sewage. The two membranes showed similar removal efficiencies of chemical oxygen demand (COD), ammonia, and total nitrogen (TN). The average effluent COD removal efficiencies, effluent ammonia, and effluent TN removal efficiencies were approximately 94.00%, 0.19 mg/L, and 28.22%, respectively. The metal membrane showed lower inherent membrane resistance of 0.27 × 1011 m−1, higher critical flux of 0.7 m3/(m2d), higher anti-fouling ability, and slower transmembrane pressure increasing rate compared with the PES membrane. The main fouling mechanism of the metal membrane was cake formation, whereas that of the PES membrane was pore blocking. The metal membrane was easy to recover after fouling. The results of the study suggest that the metal membrane can be potentially applied in a membrane bioreactor. © 2014 Balaban Desalination Publications. All rights reserved. Source

Liang J.,Shenyang University of Technology | Yu J.,Esteve Huayi Pharmaceutical Co. | Cui L.,Shenyang University of Technology | Wang X.,Shenyang University of Technology | And 4 more authors.
2011 International Conference on Remote Sensing, Environment and Transportation Engineering, RSETE 2011 - Proceedings

The treatment of high concentration organic wastewater by microwave Fenton process was studied in this paper. The input volume of Fenton reagent, microwave power, reaction time, initial pH value is investigated to study the impact of the effect of the high concentration organic wastewater treatment. The optimum condition of Microwave-Fenton oxidation is: the pH reaching 3, Fenton reagent composition ratio of n(H2O2):n(Fe2+) being 75:1, the volume ratio of Fenton reagent and waste water being 1:10, the microwave power reaching 640W, accompanied by medium speed magnetic stirring, microwave irradiation time reaching 10min.The removal rate of COD is 83.05%, the removal rate of colority reached 100%. © 2011 IEEE. Source

Discover hidden collaborations