Publications by authors named "Bai-Hang Zhao"

Salinity poses a significant obstacle to the bio-decolorization of azo dyes. However, the underlying responding mechanisms of bio-decolorization bacteria remain unclear. Shewanella putrefaciens CN32 (S.

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Copper oxide nanoparticles (CuO NPs) and ciprofloxacin (CIP) have ecological risk to humans and ecosystems. Polyvinylchloride microplastics (PVC MPs), as a representative of microplastics, may often coexist with CuO NPs and CIP in wastewater treatment systems due to their widespread application. However, the co-impact of PVC MPs in wastewater systems contained with CuO NPs and CIP on nitrogen removal and ecological risk is not clear.

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Nanoparticles and antibiotics are toxic to humans and ecosystems, and they inevitably coexist in the wastewater treatment plants. Hence, the co-existence effects and stress mechanism of copper (II) oxide nanoparticles (CuO NPs) and ciprofloxacin (CIP) on simultaneous nitrification, endogenous denitrification and phosphorus removal (SNEDPR) by aerobic granular sludge (AGS) were investigated here. The co-existence stress of 5 mg/L CuO NPs and 5 mg/L CIP resulted in the synergistic inhibitory effect on nutrient removal.

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Quorum sensing (QS) and quorum quenching (QQ) are common phenomena in microbial systems and play an important role in the nitrification process. However, rapidly start up partial nitrification regulated by N-acyl-homoserine lactones (AHLs)-mediated QS or QQ has not been reported. Hence, we chose N-butyryl homoserine lactone (C-HSL) and N-hexanoyl homoserine lactone (C-HSL) as the representative AHLs, and Vanillin as the representative quorum sensing inhibitor (QSI) combined intermittent aeration to investigate their effects on the start-up process of partial nitrification.

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Anaerobic ammonia oxidizing (anammox) has already been recognized as an innovative and economical nitrogen removal technology. However, the effect of heavy metals on anammox bacteria in aquatic ecosystem remains largely unknown. Ni(II) is a common kind of heavy metals detected in industrial wastewater and municipal sewage treatment plants.

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Anaerobic ammonium oxidation (ANAMMOX) is widely used for treatment of ammonium-rich wastewater because of its economic and environmental benefits. However, ANAMMOX bacteria are sensitive to environmental conditions, especially to heavy metals. The short-term and long-term effects of Ni(Ⅱ) on ANAMMOX were studied by batch and continuous flow experiments, respectively.

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Steroid estrogens, as typical endocrine disrupting chemicals (EDCs), have raised an increasing concern due to their endocrine disrupting effects on aquatic animals and potential hazards on human health. Batch experiments were conducted to study 17 beta-estradiol (E2) removal and Estradiol Equivalent Quantity (EEQ) elimination by anaerobic granular sludge (AnGS) combined with different valence iron sources. Results showed that E2 was effectively biodegraded and transformed into E1 by AnGS.

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Laboratory experiments were carried out to determine the long-term effects of N-acyl-homoserine lactone (AHL)-based quorum sensing on the characteristics of ANAMMOX granules in high-loaded reactors. Results clearly showed that adding 30 mg L N-octanoyl-DL-homoserinelactone (C-HSL) at the initial stage (1-40 d) of the experiment had long-term positive effects on the settleability of granules and controlled the sludge floatation effectively. C-HSL decreased the content of bound extracellular polymeric substances (B-EPS) and the ratio of protein to carbohydrate (PN/PS) by 17% and 48%, respectively and increased the relative hydrophobicity (RH) of the granules by 28%.

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Microbial internal storage processes have been demonstrated to occur and play an important role in activated sludge systems under both aerobic and anoxic conditions when operating under dynamic conditions. High-rate anaerobic reactors are often operated at a high volumetric organic loading and a relatively dynamic profile, with large amounts of fermentable substrates. These dynamic operating conditions and high catabolic energy availability might also facilitate the formation of internal storage polymers by anaerobic microorganisms.

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Active sludge was from a pilot-scale synthetic ammonia industrial wastewater treatment plant with a strengthen anoxic-oxic (A/O) technology. The zero order kinetic model was suit for describing shortcut and complete denitrification process. Experimental results showed that shortcut denitrification could reduce 14.

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Despite of the significance of the anaerobic digestion of lignocellulosic materials, only a limited number of studies have been carried out to evaluate the lignocellulosic digestion kinetics, and information about the modeling of this process is limited. In this work, a mathematical model, based on the Anaerobic Digestion Model No.1 (ADM1), was developed to describe the anaerobic conversion of lignocellulose-rich aquatic plants, with cattail as an example, by rumen microbes.

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