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Lead exposure is associated with risk of impaired coagulation in preschool children from an e-waste recycling area Полный текст
2018
Zeng, Zhijun | Huo, Xia | Zhang, Yu | Xiao, Zhehong | Zhang, Yuling | Xu, Xijin
Environmental lead exposure leads to various deleterious effects on multiple organs and systems, including the hematopoietic system. To explore the effects of lead exposure on platelet indices in preschool children from an informal, lead-contaminated electronic waste (e-waste) recycling area, we collected venous blood samples from 466 preschool children (331 from an e-waste area (Guiyu) and 135 from a non-e-waste area (Haojiang)). Child blood lead levels (BLLs) were determined by graphite furnace atomic absorption spectrophotometry, while platelet indices were quantified using a Sysmex XT-1800i hematology analyzer. Higher blood lead levels are observed in e-waste lead-exposed preschool children. Significant relationships between high blood lead levels (exceeding current health limits) and elevated platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV), and platelet large cell ratio (P-LCR) were also uncovered. Furthermore, the median PLT and PCT levels of children from the exposed group both exceeded the respective recommended maximum reference range value, whereas the reference group did not. Location of child residence in Guiyu and BLLs were both risk factors related to platelet indices. These results suggest that high blood lead exposure from e-waste recycling may increase the risk of an amplified coagulation process through the activation of platelets in preschool children.
Показать больше [+] Меньше [-]Effects of landscape plant species and concentration of sewage sludge compost on plant growth, nutrient uptake, and heavy metal removal Полный текст
2018
Chu, Shuangshuang | Jacobs, Douglass F. | Liao, Dandan | Liang, Liyin L. | Wu, Daoming | Chen, Peijiang | Lai, Can | Zhong, Fengdi | Zeng, Shucai
Landscape plants have great potentials in heavy metals (HMs) removal as sewage sludge compost (SSC) is increasingly used in urban forestry. We hypothesize that woody plants might perform better in HMs phytoremediation because they have greater biomass and deeper roots than herbaceous plants. We tested the differences in growth responses and HMs phytoremediation among several herbaceous and woody species growing under different SSC concentrations through pot experiments. The mixing percentage of SSC with soil at 0%, 15%, 30%, 60, and 100% were used as growth substrate for three woody (Ficus altissima Bl., Neolamarckia cadamba (Roxb.) Bosser, and Bischofia javanica Bl.) and two herbaceous (Alocasia macrorrhiza (L.) G. Don and Dianella ensifolia (L.) DC) plants. Results showed that the biomass, relative growth rate, and nutrient uptake for all plants increased significantly at each SSC concentration compared to the control; woody plants had higher biomass and nutrient use efficiency than herbaceous plants. All plants growing in SSC-amended soils accumulated appreciable amounts of HMs and reduced the contents of HMs present in the substrates. The woody plants were generally more effective than herbaceous plants in potentials of HMs phytoextraction, but A. macrorrhiza showed higher bioconcentration and translocation of Cu and Zn and D. ensifolia had higher bioconcentration and translocation of Cd than woody plants. The optimal application concentrations were 30% or less for woody plants and 15% for herbaceous plants for plant growth and ecological risk control, respectively. Intercropping suitable woody and herbaceous landscape plants in urban forestry might have promising potentials to minimize the ecological risks in the phytoremediation of SSC.
Показать больше [+] Меньше [-]Effect of environmental factors on enhanced adsorption and photocatalytic regeneration of molecular imprinted TiO2 polymers for fluoroquinolones Полный текст
2018
Wei, Dong | Li, Song | Fang, Lei | Zhang, Yan
The molecular imprinting technique combined with photocatalysis was used in the removal of fluoroquinolones. In this study, we prepared molecular imprinted polymers (MIPs) and investigated the adsorption and photocatalytic regeneration performance, followed by the effect of different environmental factors and photoproduct identification. Compared with non-imprinted polymers (NIPs) and P25, MIPs had a better adsorption performance towards norfloxacin with the removal efficiency of 77.1% in 1 h. pH, humic acid, and high valence ions had significant effects on the adsorption performance. Under neutral condition, the adsorption effect of MIPs was better than that of acidic and alkaline condition. The removal efficiency declined to 25.9% when pH reached 11. The removal efficiency gradually improved with the concentration of humic acid increasing. The adsorption efficiency of MIPs in surface water was only 12.6% lower than that of ultrapure water, which indicated that molecular imprinting process improved the anti-interference property. The photodegradation rate was 0.114 min⁻¹ when the concentration of norfloxacin was 1 mg L⁻¹. Norfloxacin was oxidized with aldehyde group or hydroxyl. The adsorption removal efficiency of MIPs did not decline apparently after 11 adsorption-photocatalytic regeneration cycles, which suggested that the in-situ regeneration and sustainable use of MIPs were achievable in organic pollutant control.
Показать больше [+] Меньше [-]Surface modification of sludge-derived carbon by phosphoric acid as new electrocatalyst for degradation of acetophenone Полный текст
2018
Yu, Yang | Huang, Fei | He, Yide | Liu, Xiyang | Xu, Yanhua | Zhang, Yongjun
Sludge-derived carbons (SCs) were modified by different acids and used as electrocatalyst for electrochemical oxidation degradation of acetophenone. The results showed that SC treated with phosphoric acid (H₃PO₄-SC) exhibited the highest catalytic activity. The degradation efficiency of acetophenone reached 87.0%, and TOC removal was 72.3% under the conditions of 100 mg L⁻¹ acetophenone, 90 mA cm⁻², and 180 min reaction time. The element content and chemical state of H₃PO₄-SC were measured by XRF, XRD, TGA, FTIR, and Mössbauer spectra, and the results indicated that ferric iron and phosphate on the surface of H₃PO₄-SC might play the main role in acetophenone degradation. The carbonyl-¹³C-labeled acetophenone was first used to investigate the degradation of acetophenone in electrochemical oxidation by NMR.
Показать больше [+] Меньше [-]Optimization of non-thermal plasma efficiency in the simultaneous elimination of benzene, toluene, ethyl-benzene, and xylene from polluted airstreams using response surface methodology Полный текст
2018
Najafpoor, AliAsghar | Jonidi Jafari, Ahmad | Hosseinzadeh, Ahmad | Khani Jazani, Reza | Bargozin, Hasan
Treatment with a non-thermal plasma (NTP) is a new and effective technology applied recently for conversion of gases for air pollution control. This research was initiated to optimize the efficient application of the NTP process in benzene, toluene, ethyl-benzene, and xylene (BTEX) removal. The effects of four variables including temperature, initial BTEX concentration, voltage, and flow rate on the BTEX elimination efficiency were investigated using response surface methodology (RSM). The constructed model was evaluated by analysis of variance (ANOVA). The model goodness-of-fit and statistical significance was assessed using determination coefficients (R ² and R ²ₐdⱼ) and the F-test. The results revealed that the R ² proportion was greater than 0.96 for BTEX removal efficiency. The statistical analysis demonstrated that the BTEX removal efficiency was significantly correlated with the temperature, BTEX concentration, voltage, and flow rate. Voltage was the most influential variable affecting the dependent variable as it exerted a significant effect (p < 0.0001) on the response variable. According to the achieved results, NTP can be applied as a progressive, cost-effective, and practical process for treatment of airstreams polluted with BTEX in conditions of low residence time and high concentrations of pollutants.
Показать больше [+] Меньше [-]Removal of tetracyclines, sulfonamides, and quinolones by industrial-scale composting and anaerobic digestion processes Полный текст
2018
Liu, Hang | Pu, Chengjun | Yu, Xiaolu | Sun, Ying | Chen, Junhao
This study evaluated and compared the removal of antibiotics by industrial-scale composting and anaerobic digestion at different seasons. Twenty compounds belonged to three classes of widely used veterinary antibiotics (i.e., tetracyclines, sulfonamides, and quinolones) were investigated. Results show that of the three groups of antibiotics, tetracyclines were dominant in swine feces and poorly removed by anaerobic digestion with significant accumulation in biosolids, particularly in winter. Compared to that in winter, a much more effective removal (> 97%) by anaerobic digestion was observed for sulfonamides in summer. By contrast, quinolones were the least abundant antibiotics in swine feces and exhibited a higher removal by anaerobic digestion in winter than in summer. The overall removal of antibiotics by aerobic composting could be more than 90% in either winter or summer. Nevertheless, compost products from livestock farms in Beijing contained much higher antibiotics than commercial organic fertilizers. Thus, industrial composting standards should be strictly applied to livestock farms to further remove antibiotics and produce high quality organic fertilizer.
Показать больше [+] Меньше [-]Alternative soilless media using olive-mill and paper waste for growing ornamental plants Полный текст
2018
Chrysargyris, Antonios | Antoniou, Omiros | Tzionis, Andreas | Prasad, Munoo | Tzortzakis, Nikolaos
Peat-based growing media are not ecologically sustainable and peat extraction threatens sensitive peatland ecosystem. In this study, olive-stone waste (OSW) and paper waste (PW) were used in different ratios—as growing media—for ornamental crop production, as peat (P) substitutes. Marigold (Calendula officinalis L.), petunia (Petunia x hybrita L.) and matthiola (Matthiola incana L.) plants were grown in (1) P (100%), (2) P:OSW (90%:10%), (3) P:OSW (70%:30%), and (4) P:OSW:PW (60%:20%:20%). The physicochemical properties of these substrates and the effects on plant growth were determined. The addition of 10–30% OSW into the substrate increased marigold height compared to plants grown in 100% peat. No differences in plant size, plant biomass (leaves and flowers), and dry matter content were found. Adding PW, in combination with OSW, maintained marigold height and total number of flowers produced to similar levels as in plants grown in 100% peat. In matthiola, adding 30% OSW into the substrate reduced plant size and fresh weight, but not plant height. No differences were observed when plants grew in lower OSW (i.e., 10%) content. Petunia’s height, its total number of flowers and flower earliness (flower opening) were increased in the presence of OSW compared to the plants grown in 100% peat. The addition of OSW did not affect petunia’s size and fresh weight among treatments. The addition of PW suppressed several plant growth-related parameters for both matthiola and petunia. The insertion of OSW did not change leaf chlorophyll content whereas the presence of PW decreased chlorophylls for marigold, petunia, and matthiola. Both OSW and PW altered the content of total phenolics and antioxidant capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) in leaves and flowers for marigold and petunia. Both 30% OSW and PW increased antioxidative enzyme metabolism due to the increased damage index and lipid peroxidation observed in plants. Leaf N and P content decreased in PW-based media, while matthiola displayed visual phytotoxicity symptoms when PW was added into the substrate. The present work indicates that up to 30% of OSW can replace peat for marigold and petunia growing and only up to 10% of OSW for matthiola, while the addition of PW on top of OSW is not recommended, so further research is needed.
Показать больше [+] Меньше [-]Catalytic degradation of sulfaquinoxalinum by polyester/poly-4-vinylpyridine nanofibers-supported iron phthalocyanine Полный текст
2018
Li, Nan | Lu, Panting | He, Cuixia | Lu, Wangyang | Chen, Wenxing
Iron (II) phthalocyanine (FePc) supported on electrospun polyester/poly-4-vinylpyridine nanofibers (PET/P4VP NFs) was prepared by stirring in tetrahydrofuran. The resulting product was confirmed and characterized by ultraviolet-visible diffuse reflectance spectroscopy, attenuated total reflection Fourier transform infrared spectra, X-ray photoelectron spectroscopy, gas chromatography/mass spectrometry, and ultra-performance liquid chromatography. More than 95% of sulfaquinoxalinum (SQX) could be removed by the activation of hydrogen peroxide in the presence of FePc-P4VP/PET with a PET and P4VP mass ratio of 1:1. This system exhibited a high catalytic activity across a wide pH and temperature range. The degradation rates of SQX achieved 100, 95, and 78% at a pH of 3, 7, and 9, respectively, and the degradation rates of SQX are more than 80% at the temperature ranging from 35 to 65 °C. DMSO₂ could be detected by gas chromatography/mass spectrometry after the addition of DMSO, suggesting the formation of the high-valent iron intermediates in this catalytic system. In addition, the electron paramagnetic resonance experiments proved that free radicals did not dominate the reaction in our system. Therefore, the high-valent iron intermediates were proposed to the main active species in the FePc-P4VP/PET/hydrogen peroxide system. In summary, the heterogeneous catalytic processes with non-radical catalytic mechanism might have better catalytic performance for the removal of organic pollutants, which can potentially be used in wastewater treatment.
Показать больше [+] Меньше [-]Influence of phosphorous fertilization on copper phytoextraction and antioxidant defenses in castor bean (Ricinus communis L.) Полный текст
2018
Huang, Guoyong | Rizwan, MuhammadShahid | Ren, Chao | Guo, Guangguang | Fu, Qingling | Zhu, Jun | Hu, Hongqing
Application of fertilizers to supply appropriate nutrients has become an essential agricultural strategy for enhancing the efficiency of phytoremediation in heavy metal contaminated soils. The present study was conducted to investigate the beneficial effects of three types of phosphate fertilizers (i.e., oxalic acid-activated phosphate rock (APR), Ca(H₂PO₄)₂, and NaH₂PO₄) in the range of 0–600 mg P kg⁻¹ soil, on castor bean growth, antioxidants [antioxidative enzymes and glutathione (GSH)], and Cu uptake. Results showed that with the addition of phosphorus fertilizers, the dry weight of castor bean and the Cu concentration in roots increased significantly, resulting in increased Cu extraction. The phosphorus concentration in both shoots and roots was increased as compared with the control, and the Ca(H₂PO₄)₂ treatment had the greatest effect. Application of APR, NaH₂PO₄, and Ca(H₂PO₄)₂ reduced the malondialdehyde (MDA) content, and the activity of the two antioxidant enzymes superoxide dismustase (SOD, EC 1.15.1.1) and catalase (CAT, EC 1.11.1.6) in the leaves of castor bean. GSH concentration in leaves increased with the increasing levels of phosphorus applied to soil as well as the accumulation of phosphorus in shoots, compared to the control. These results demonstrated that the addition of phosphorus fertilizers can enhance the resistance of castor bean to Cu and increase the Cu extraction efficiency of the plant from contaminated soils.
Показать больше [+] Меньше [-]Origins and discrimination between local and regional atmospheric pollution in Haiphong (Vietnam), based on metal(loid) concentrations and lead isotopic ratios in PM10 Полный текст
2018
Chifflet, Sandrine | Amouroux, David | Bérail, Sylvain | Barre, Julien | Van, Thuoc Chu | Baltrons, Oriol | Brune, Justine | Dufour, Aurélie | Guinot, Benjamin | Marí i Cerezo, Xavier
Southeast Asia is a hotspot of anthropogenic emissions where episodes of recurrent and prolonged atmospheric pollution can lead to the formation of large haze events, giving rise to wide plumes which spread over adjacent oceans and neighbouring countries. Trace metal concentrations and Pb isotopic ratios in atmospheric particulate matter < 10 μm (PM₁₀) were used to track the origins and the transport pathways of atmospheric pollutants. This approach was used for fortnightly PM₁₀ collections over a complete annual cycle in Haiphong, northern Vietnam. Distinct seasonal patterns were observed for the trace metal concentration in PM₁₀, with a maximum during the Northeast (NE) monsoon and a minimum during the Southeast (SE) monsoon. Some elements (As, Cd, Mn) were found in excess according to the World Health Organization guidelines. Coal combustion was highlighted with enrichment factors of As, Cd, Se, and Sb, but these inputs were outdistanced by other anthropogenic activities. V/Ni and Cu/Sb ratios were found to be markers of oil combustion, while Pb/Cd and Zn/Pb ratios were found to be markers of industrial activities. Pb isotopic composition in PM₁₀ revealed an important contribution of soil dusts (45–60%). In PM₁₀, the Pb fraction due to oil combustion was correlated with dominant airflow pathways (31% during the north-easterlies and 20% during the south-easterlies), and the Pb fraction resulting from industrial emissions was stable (around 28%) throughout the year. During the SE monsoon, Pb inputs were mainly attributed to resuspension of local soil dusts (about 90%), and during the NE monsoon, the increase of Pb inPM₁₀ was due to the mixing of local and regional inputs.
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