WATER RESEARCH
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2021
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IF 11.236
Yangrui Huang,Shunke Ding,Lei Li,Qingying Liao,Wenhai Chu,Huaizheng Li
Ultrasound techniques have gained increased interest in environmental remediation because of their promising performance and reagent-free nature. This study investigated the effects of ultrasound-coagulation on Microcystis aeruginosa removal, disinfection by-product (DBP) formation during subsequent chlorination, and acute toxicity and DBP-associated toxicity variations in chlorinated effluents. Compared with coagulation using polymeric aluminum chloride (5 mg-Al/L) alone, ultrasound-coagulation showed significantly enhanced turbidity removal, with the removal ratio increasing from 51% to 87%–96%. Although the addition of ultrasound may not substantially improve and even deteriorate the coagulation removal of DOC following the leakage of intracellular organic matter, the significantly improved DBP control was achieved as the cells dominated DBP formation. With the addition of ultrasound, the chlorine demand, aggregate DBP concentration and total organic halogen concentration reductions in the chlorinated M. aeruginosa solution increased from 15%, 47% and 52% (coagulation alone), respectively, to 56%–78%, 56%–80% and 68%–89%. The enhanced DBP mitigation was mainly attributed to the enhanced algal removal. Similarly, the acute toxicity and DBP-associated toxicity of chlorinated effluents further decreased from 100% and 0.0092 (coagulation alone) to 30%–88% and 0.0029–0.0060. Therefore, ultrasound-enhanced coagulation is a promising strategy for urgent algal removal, DBP mitigation and toxicity abatement.
研究领域:
环境科学
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水处理工程
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DOI
PubMed
高影响因子
CHEMOSPHERE
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2019
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IF 5.108
Xueyin Wu,Aixi Tang,Xiaochao Bi,Thanh H. Nguyen,Baoling Yuan
Surface water contaminated with algae and with enteric viruses is a global problem. When surface water is used as a drinking water source, it is important to know the influence of algal organic matter on the disinfection of viruses. In this work, we studied the disinfection efficacy of ferrate and the influence of algal organic matter on the disinfection. We determined the MS2 inactivation kinetics by ferrate under three pH conditions (7, 8, and 8.7). The experimental results and pH-dependent calculation suggest that H 2 FeO 4 and HFeO 4 − are 1935 and 8 times as effective as FeO 4 2− in MS2 inactivation. We also found that intracellular algal organic matter (IAOM) had a stronger effect on MS2 inactivation kinetics than extracellular algal organic matter (EAOM) suggesting that IAOM led to higher consumption of Fe(VI) compared to EAOM. At pH 8.7, while significant consumption of FeO 4 2− by as low as 8 mg C/L of EAOM and 2 mg C/L of IAOM was detected, MS2 inactivation was negatively influenced only when 13 mg C/L of IAOM present. This study showed that it is important to control pH and to determine the concentration of algal organic matter if ferrate is used for disinfection of surface water contaminated with algae.
研究领域:
环境科学
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水处理工程
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病毒学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2015
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IF 4.321
Lei Li,Haicheng Guo,Chen Shao,Shuili Yu,Daqiang Yin,Naiyun Gao,Ning Lu
The presence of algal organic matter (AOM) and emerging organic contaminants in surface drinking water sources has received increasing attention recently. Nevertheless, interactions between these two harmful co-existing compounds in water sources have rarely been reported. This study investigated the influence of AOM, including intracellular organic matter (IOM) and extracellular organic matter (EOM), on the photo-degradation of Diuron, under UV and visible light (VL) irradiation. Kinetics analyses indicated that both the direct and indirect photolysis of Diuron followed a pseudo-first-order reaction ( R 2 > 0.98). Diuron was rapidly removed under UV irradiation accompanied by minor impacts from AOM. Under VL irradiation, the photo-excited phycocyanin in the IOM was capable of accelerating Diuron degradation, whereas the coexistence of other organic compounds in the IOM inhibited the reaction due to a screening effect, resulting in a slower overall rate of Diuron degradation. By comparison, EOM promoted the reactions when pH exceeded 5.0. The AOM-mediated generation of triplet DOM ( 3 DOM ∗ ) accounted for 82% and 64% of the Diuron removal in the presence of IOM and EOM, respectively. Spectral excitation–emission matrices produced by AOM in solutions demonstrated the primary mechanisms of the co-existing AOM on Diuron degradation.
研究领域:
环境科学
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水处理工程
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光化学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2014
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IF 4.331
Jinjin Wan,Peiyong Guo,Xiaofang Peng,Keqi Wen
Erythromycin, a macrolide antibiotic, is commonly used in human life. This compound and its derivatives have been detected in various aquatic compartments and may pose a serious threat to aquatic organisms. This study investigated the effects of erythromycin on the growth, antioxidant system and photosynthesis of Microcystis flos-aquae . The results showed that at 0.001–0.1 μg L −1 , erythromycin could stimulate the growth of M. flos-aquae and increase its photosynthetic activity; however, it did not significantly increase the activities of superoxide dismutase (SOD) and catalase (CAT) or the levels of malondialdehyde (MDA) and reactive oxygen species (ROS). In contrast, the growth of M. flos-aquae was significantly inhibited ( p < 0.01) at high levels of erythromycin, reaching an inhibition rate of 81.6% at 40 μg L −1 erythromycin. At the same time, the activities of SOD and CAT along with MDA content also increased significantly ( p < 0.01), indicating that the high concentrations of erythromycin caused a severe oxidative stress on algae. However, the balance between oxidants and antioxidant enzymes were disrupted because ROS content simultaneously increased. In addition, the fluorescence parameters of M. flos-aquae decreased significantly with both exposure time and increasing concentration of erythromycin, indicating that photosynthesis was inhibited.
研究领域:
环境科学
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水生毒理学
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藻类学
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产品关联
DOI
PubMed
高影响因子
Algal Research-Biomass Biofuels and Bioproducts
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2018
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IF 3.745
Wenwen Kong,Suiliang Huang,Feifei Shi,Jianguo Zhou,Yibei Feng,Yao Xiao
A combination of Logistic and Monod functions was proposed in this paper to study Microcystis aeruginosa growth in incubator experiments. This enables the Microcystis aeruginosa growth dynamics to be better described in incubator experiments and its parameters to be calculated more accurately. This method was justified by the data from the experiment and applied to study the effect of prometryn on Microcystis aeruginosa growth. In the experiment, a different concentrations of prometryn (0, 50, 100 and 200 μg·L −1 ) were added to the culture medium; the algal cell density, concentrations of orthophosphate (PO 4 3− -P) and ammonia nitrogen (NH 4 + -N) were measured. The results show that Microcystis aeruginosa growth with time can be well described using the Logistic function . The maximum algae densities of Microcystis aeruginosa corresponding to the four prometryn concentrations are 11.7 × 10 6 , 8.1 × 10 6 , 5.6 × 10 6 and 3.0 × 10 6 cells·mL −1 , respectively. The derived formula for the specific growth rate, growth rate and inhibition rate using Logistic function agreed reasonably well with the measured data. It was found that variations of consumed nutrients concentrations (PO 4 3− -P and NH 4 + -N) can also be well described by the Logistic function. A function that describes the relationship between algal densities and consumed nutrient (PO 4 3− -P and NH 4 + -N) concentrations is also derived from the Logistic function. Combination of Monod and Logistic functions can better describe relationship between specific growth rates and nutrients concentrations compared to the use of Monod function alone. In general, the half saturation coefficient, K c for PO 4 3− -P (4.74 × 10 −4 , 1.99 × 10 −3 , 5.54 × 10 −3 and 3.87 × 10 −2 mg·L −1 ) and K c for NH 4 + -N (1.80 × 10 −3 , 5.84 × 10 −3 , 5.23 × 10 −3 and 1.06 × 10 −2 mg·L −1 ) in Monod function increase with increasing prometryn concentrations, which indicates that the affinity of algae growth to PO 4 3− -P and NH 4 + -N decrease with increasing prometryn concentrations. In addition, relationships between nutrients concentrations and time can be derived by combining of Monod and Logistic functions, which agree well with the measured data. It is concluded that the combined application of Monod and Logistic functions provides a promising and more robust method of studying algal growth in incubator experiments.
研究领域:
水生生态学
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环境科学
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微生物学
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毒理学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Huiping Wang,Yanling Yang,Zhiwei Zhou,Xing Li,Jingfeng Gao,Rui Yu,Jiaqi Li,Nan Wang,Haiqing Chang
Photocatalysis is an efficient advanced oxidation process that provides a promising alternative for pollution control during algal blooms in lakes or water reservoirs. Previous research has mainly focused on the destruction of algal cells by photocatalysis, whereas the release and control of concomitant secretions specially intracellular organic matter (IOM) is undervalued. Herein, we studied the removal efficiency and mechanism of algal IOM extracted from Microcystis aeruginosa during stationary phase by the combined process of pre-photocatalysis with a novel composite of Bi 2 O 3 -TiO 2 /PAC (Bi-doped TiO 2 nano-composites supported by powdered activated carbon) followed by enhanced coagulation with aluminum sulfate (AS) coagulant. Optimized photocatalysis and coagulation combined treatment (PC) was indicated to enhance IOM removal with 64%, 92% and 100% for DOC, absorbance at 254 nm (UV 254 ) and the optical density at 680 nm (OD 680 ) respectively. Pre-photocatalysis reduced the required AS coagulant dose and weakened the effect of solution pH. Photocatalysis was more inclined to remove humic substances and building blocks than high-molecular weight components, while coagulation alone displayed preference for high-molecular weight biopolymers and protein-like substance. Pre-photocatalysis was complementary with subsequent coagulation for efficient removal of protein-like substances and fractionation with medium molecular weight of 0.5–1 kDa. The produced flocs revealed that the Bi 2 O 3 -TiO 2 /PAC adsorbing IOM acted as a flocculation core to improve coagulation performance. Besides, the combined PC process was proved to perform well to co-existing algal pollution without damaging cells integrity and enhanced algal cells removal from 26% by coagulation alone to 61%. Therefore, this combined treatment was an effective method for the removal of IOM of Microcystis aeruginosa and control cyanobacteria bloom.
研究领域:
环境科学
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水处理工程
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产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Hangjun Zhang,Bingzhi Yu,Xizi Li,Yan Li,Yuchi Zhong,Jiafeng Ding
Harmful algal blooms caused by cyanobacteria in drinking water have posed serious threats to destroy aquatic ecosystems , and the toxins they produce are harmful to human and animal health. Herein, the feasibility of removing Microcystis aeruginosa ( M. aeruginos ) and microcystin-LR ( MC-LR ) by free radicals produced by simple-atomic iron-doped g-C 3 N 4 (Fe-g-C 3 N 4 )-activated peroxydisulfate (PDS) was studied. Pristine g-C 3 N 4 and three kinds of Fe-g-C 3 N 4 with different compositions were successfully synthesized and characterized. When the initial algae density was 2.5 × 10 6 cells·mL −1 , approximately 96.25 % of M. aeruginosa cells were inactivated with 2.0 g·L −1 Fe-g-C 3 N 4 and 4.0 mM PDS under the conditions of pH 7.0, and MC-LR could also be effectively degraded. The activated system can effectively remove M. aeruginosa, and MC-LR was evaluated for its morphological characteristics, cell membrane integrity and microcystin degradation. In addition to the widely recognized reaction species (SO 4 • − and • OH), singlet oxygen ( 1 O 2 ) was another predominant radical for destroying the cell structure and removing MC-LR . The materials can be well recycled, and a possible removal mechanism was proposed. This work shows that the Fe-g-C 3 N 4 -activated PDS system is an environmentally friendly and efficient technology for algae removal and algal toxin reduction.
研究领域:
环境科学
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水处理技术
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毒理学
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产品关联
DOI
高影响因子
CHEMOSPHERE
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2021
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IF 7.086
Gongduan Fan,Zhong Chen,Shiping Gu,Banghao Du,Lihui Wang
Cyanobacterial harmful algal blooms (CyanoHABs) and the release of cyanotoxins have posed adverse impacts to aquatic system and human health. In this study, a novel self-floating Ag/ [email protected] 3 (ALFO) photocatalytic hydrogel was prepared via freeze-thaw method for removal of Microcystis aeruginosa ( M. aeruginosa ). The ALFO hydrogel performed an excellent photocatalytic activity with a 99.4% removal efficiency of chlorophyll a within 4 h. It can still remove above 95% chlorophyll a after six consecutive recycles. Besides it has also shown excellent mechanical strength and elasticity, which can ensure its use in practical applications. The mechanisms of M. aeruginosa inactivation are attributed to •O 2 − and •OH generated by the ALFO hydrogel under visible light radiation . In addition, •O 2 − and •OH can further oxidative degrade and even mineralize the leaked algae organic matter, avoiding the recurrence of CyanoHABs. What's more, the ALFO hydrogel owns good photocatalytic degradation performance for microcystins-LR (MC-LR) with a 97% removal efficiency within 90 min. A possible photocatalytic degradation pathway of MC-LR was proposed through the identification of the intermediate products during the photocatalytic reaction, which confirmed the reduction of MC-LR toxicity. This work develops recyclable a self-floating ALFO hydrogel to simultaneously inactivate M. aeruginosa and degrade MC-LR, providing a prospective method for governing and controlling CyanoHABs in practical application.
研究领域:
环境科学
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水处理
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光催化
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毒理学
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水生生态学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
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2021
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IF 8.071
Qing Yang,Yongqiang Liu,Lihong Wang,Qing Zhou,Mengzhu Cheng,Jiahong Zhou,Xiaohua Huang
Aggravating the pollution of microcystins (MCs) in freshwater environments is detrimental to aquatic living organisms and humans, and thus threatens the stability of ecosystems. Some environmental factors have been verified to promote the production of MCs in Microcystis aeruginosa , thereby aggravating the pollution of MCs. However, the effects of cerium (Ce), the most abundant rare earth element in global water environments, on the production of MCs in M. aeruginosa are unknown. Here, Lake Taihu water was selected as a representative of freshwater environments. By using interdisciplinary methods, it was found that: (1) the exposure level of Ce [Ce(III) and Ce(IV)] in Lake Taihu water is in the range of 0.271–0.282 μg/L; (2) Ce exposure in Lake Taihu water promoted the contents of three main MCs (MC-LR, MC-LW and MC-YR) in M. aeruginosa and water; (3) a cellular mechanism of Ce promoting the production of MCs in M. aeruginosa in Lake Taihu water was suggested: Ce enhanced endocytosis in cells of M. aeruginosa to promote the essential element uptake by M. aeruginosa for MC synthesis. Thus, Ce exposure in Lake Taihu water aggravates the pollution of MCs via enhancing endocytosis in cells of M. aeruginosa . The results provide reference for assessing the environmental risk of Ce in water environments, investigating the mechanism of the pollution of MCs induced by environmental factors, and developing strategies aimed at preventing and controlling the pollution of MCs.
研究领域:
环境科学
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生物学
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产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2022
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IF 10.753
Xiaowei Zheng,Liangliang Zhang,Chao Jiang,Jue Li,Yanyao Li,Xianglin Liu,Chengwei Li,Zeming Wang,Nan Zheng,Zhengqiu Fan
As plastic pollution continues to increase and plastic waste is shredded to form smaller plastic particles, there is growing concern about the potential impact of nanoplastics (NPs) on freshwater ecosystems. In this work, the effects of three surface-modified NPs, including polystyrene (PS), PS-NH 2 , and PS-COOH, on the growth, photosynthetic activity, oxidative damage, and microcystins (MCs) production/release of Microcystis aeruginosa ( M. aeruginosa ) were investigated. Results indicated that all three NPs significantly inhibited the growth of M. aeruginosa after a 96 h exposure, and the growth inhibition followed the order of PS-NH 2 > PS > PS-COOH ( p < 0.05). Meanwhile, all three NPs at the concentration of 100 mg/L significantly increased the content of intra-MCs (115 %, 147 %, and 121 % higher than the control, respectively) and extra-MCs (142 %, 175 %, and 151 % higher than the control, respectively) after a 96 h exposure ( p < 0.05). Moreover, our findings also suggested that the potential mechanisms of surface-modified PS NPs on M. aeruginosa growth and MCs production/release were associated with physical constraints, photosynthetic activity obstruct, and oxidative damage. Our findings provided direct evidence for different kinds of surface modifications of PS NPs on freshwater algae and improve the understanding of the potential risk of NPs in aquatic ecosystems.
研究领域:
环境科学
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水生生态学
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毒理学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2023
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IF 11.4
Chengyang Zhang,Guoyang Zhang,Jiyuan Jin,Hongcen Zheng,Zhiwei Zhou,Shujuan Zhang
The coexistence of selenite (Se(IV)) and acetylacetone (AA) generated a synergistic effect on the growth inhibition of a bloom-forming cyanobacterium, Microcystis aeruginosa. The mechanism behind this phenomenon is of great significance in the control of harmful algal blooms. To elucidate the role of Se(IV) in this effect, the reactions in ternary solutions composed of Se(IV), AA (or two other similar hydrogen donors), and quinones, especially benzoquinone (BQ), were investigated. The transformation kinetic results demonstrate that Se(IV) played a catalytic role in the reactions between AA (or ascorbic acid) and quinones. By comparison with five other oxyanions (sulfite, sulfate, nitrite, nitrate, and phosphate) and two AA derivatives, the formation of an AA-Se(IV) complexation intermediate was confirmed as a key step in the accelerated reactions between BQ and AA. To our knowledge, this is the first report on Se(IV) as a catalyst for quinone-involved reactions. Since both quinones and Se are essential in cells and there are many other chemicals of similar electron-donating properties to that of AA, the finding here shed light on the regulation of electron transport chains in a variety of processes, especially the redox balances that are tuned by quinones and glutathione.
研究领域:
环境科学
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微生物学
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生态学
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产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2022
·
IF 7.968
Yutong Han,Jingjing Zheng,Chao Jiang,Fan Zhang,Lecheng Wei,Liang Zhu
The unceasing algae blooms have led to the deterioration of water quality and ecological imbalance in the entire globe, it’s urgent to investigate its treatment and resource utilization technology . In this study, treated algae was prepared to produce the biochar and then it was utilized as a coagulant for the removal of Microcystis aeruginosa . To improve the pore structure of algae-derived biochar for improving the removal capacity of M. aeruginosa , hydrochloric acid (HCl) modification was applied and optimized by Box-Behnken model-based response surface methodology . After modification by HCl, the specific surface area, pore volume, and average pore diameter of modified algae-derived biochar (MAB) increased to 38.34 m 2 /g, 0.073 cm³ /g, and 7.42 nm, respectively. The removal efficiency of Microcystis aeruginosa (The initial cell density: 4 ×10 6 cells/mL) by the MAB reached 99.02% ± 0.18 under the optimum condition obtained with response surface experiment (dosage of 287.46 mg/L, pH of 8.2, stirring rate of 175 rpm, and stirring time of 6.4 min). At the same time, the removal efficiencies of Chl a, turbidity and total phosphorus of polluted waters reached more than 84%, 91% and 60%, respectively. The dissolved organic matters were removed synchronously, thereby reducing the disinfection by-products formation potential. Electrostatic adsorption has been determined as the predominant force during the coagulation process. In conclusion, the HCl has been proved to be an effective strategy to improve the pore structure and algal removal capacity of MAB, and the MAB could be applied as the suitable materials for the algal coagulation with the advantage of resource utilization.
研究领域:
环境科学
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水处理
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生物技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）