显示样式:     当前期刊: Chemosphere    加入关注    导出
我的关注
我的收藏
您暂时未登录!
登录
  • A novel 3D heteropoly blue type photo-Fenton-like catalyst and its ability to remove dye pollution
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Bao-Li Fei, Jian-Kai Zhong, Ni-Ping Deng, Jiang-Hong Wang, Qing-Bo Liu, Yang-Guang Li, Xiang Mei

    A environment-friendly 3D inorganic heteropoly blue (HPB) Ba2Na2 [HPWV4WVI8O40]·26H2O was directly synthesized by hydrothermal method and characterized by means of ICP, IR, XPS, X-ray single crystal and X-ray powder diffraction. It was an efficient heterogeneous photo-Fenton-like catalyst to degrade anionic dye methyl orange under visible light irradiation. It removed cationic dyes methylene blue in neutral environment and rhodamine B in acidic condition via flocculation. The removal efficiency of methylene blue and rhodamine B by flocculation was more than 95%. Moreover, it could degrade methyl orange and flocculate rhodamine B at the same time. For MO and MO-RhB solutions, the degradation rates of MO in 60 min were 85.5% and 49.1%, respectively. Furthermore, the possible pathways for the production of active species in the MO degradation reaction were discussed. This is the first HPB constructed with 4e-reduced phosphotungstate, Ba and Na ions, having the properties of photo-Fenton-like catalyst and flocculant.

    更新日期:2018-01-13
  • Humic acid alleviates the ecotoxicity of graphene-family materials on the freshwater microalgae Scenedesmus obliquus
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Ying Zhang, Tiantian Meng, Xi Guo, Ruixin Yang, Xiaohui Si, Jiti Zhou

    The extensive application of graphene-family materials (GFMs) has increased its potential risk to aquatic organisms. However, the influence of humic acid (HA) on the biotoxicity of GFMs has not clarified. Here, we conduct a study on the toxicity of four GFMs, i.e. graphene (G), graphene oxide (GO), carboxyl-modified graphene (G-COOH) and amine-modified graphene (G-NH2), with or without HA, using Scenedesmus obliquus (S. obliquus) as model organism. Our results showed that the four GFMs induced significant inhibition on cell growth and Chlorophyll-a (Chl-a) synthesis, loss of cell viability and membrane integrity as well as mitochondrial membrane potential (MMP), where G exhibited the highest toxicity with median effect concentration (EC50) of 8.2 mg L−1, and G-NH2 exhibited the lowest toxicity with EC50 of 84.0 mg L−1. Meanwhile, HA mitigated the toxicity of GFMs in the order of G-NH2 > G-COOH > GO > G for the most of endpoints. Furthermore, three possible mechanisms of the HA alleviation on toxicity were speculated as: (1) reduce the contact of GFMs with algae cells through regulating the structures and surface negative charges of GFMs; (2) mitigate physical penetration and damage through decreasing the deposition of GFMs on cells by interacting with HA; (3) react as an antioxidant with intracellular reactive oxygen species (ROS) and extracellular hydroxyl radical ( radical dot OH). This work provides useful information for the environmental toxicity of GFMs and the possible antidotal mechanisms in the presence of HA, which could aid to avoiding the overestimation of potential risk of GFMs in natural aquatic environment.

    更新日期:2018-01-13
  • Carbon and nitrogen mineralization and enzyme activities in soil aggregate-size classes: Effects of biochar, oyster shells, and polymers
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Yasser Mahmoud Awad, Sang Soo Lee, Ki-Hyun Kim, Yong Sik Ok, Yakov Kuzyakov

    Biochar (BC) and polymers are cost-effective additives for soil quality improvement and long-term sustainability. The additional use of the oyster shells (OS) powder in BC- or polymer-treated soils is recommended as a nutrient source, to enhance aggregation and to increase enzyme activities. The effects of soil treatments (i.e., BC (5 Mg ha−1) and polymers (biopolymer at 0.4 Mg ha−1 or polyacrylamide at 0.4 Mg ha−1) with or without the OS (1%)) on the short-term changes were evaluated based on a 30-day incubation experiment with respect to several variables (e.g., CO2 release, NH4+ and NO3− concentrations, aggregate-size classes, and enzyme activities in an agricultural Luvisol). The BC and BP with the addition of OS increased the portion of microaggregates (<0.25 mm) relative to the control soil without any additions, while PAM alone increased the portion of large macroaggregates (1–2 mm). Concentrations of NO3− also increased in soils treated with OS, OS + BC, and OS + BP as result of the increased chitinase and leucine aminopeptidase activities. The BC and BP when treated with the additional OS had significant short-term impacts on N mineralization without affecting C mineralization in soil. Consequently, the combination of BC or BP with OS was seen to accelerate N turnover without affecting C turnover (and related C losses) from soil. As such, the addition of these additives contributed considerably to the improvement of soil fertility and C sequestration.

    更新日期:2018-01-12
  • Chemosphere novel procedures for whole organism detection and quantification of fluorescence as a measurement for oxidative stress in zebrafish (Danio rerio) larvae
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Carina Lackmann, Monica Martinez Santos, Sandra Rainieri, Alejandro Barranco, Henner Hollert, Petra Spirhanzlova, Mirna Velki, Thomas-Benjamin Seiler
    更新日期:2018-01-12
  • Effects of inorganic ions and natural organic matter on the aggregation of nanoplastics
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Li Cai, Lingling Hu, Huahong Shi, Junwei Ye, Yunfei Zhang, Hyunjung Kim
    更新日期:2018-01-12
  • Mercury in a stream-lake network of Andean Patagonia (Southern Volcanic Zone): Partitioning and interaction with dissolved organic matter
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Carolina Soto Cárdenas, María del Carmen Diéguez, Claudia Queimaliños, Andrea Rizzo, Vesna Fajon, Jože Kotnik, Milena Horvat, Sergio Ribeiro Guevara
    更新日期:2018-01-12
  • The embryonic developmental effect of sedaxane on zebrafish (Danio rerio)
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Hongzhou Yao, Jianping Yu, Ying Zhou, Qingqing Xiang, Chao Xu

    The succinate dehydrogenase inhibitor (SDHI) fungicides have been extensively used in agriculture, and some of their potential ecological risks to aquatic organisms have been demonstrated recently. Sedaxane (SDX) is a broad spectrum SDHI fungicide. Despite being extensively used in environment, little is known about its potential developmental effect in zebrafish embryo. This study examined the effects of which SDX triggered in zebrafish through embryonic development assessments. Results show that SDX induced mortality, hatch delay and failure in zebrafish embryos, which were concentration dependent. In addition, several developmental abnormalities were observed at 2 mg/L and higher concentrations, including edema, microcephaly, body deformation, and swim bladder not fully inflated. SDX exposure influenced reactive oxygen species, malondialdehyde, peroxidase, glutathione S-transferase, superoxide dismutase and glutathione in live larvae, which indicated that oxidative stress was caused in zebrafish. Furthermore, SDX induced decrease of succinate dehydrogenase activity in zebrafish larvae. These results provide toxicological data of SDX on developing zebrafish embryo, which could be help for further understanding the potential risk on the environment.

    更新日期:2018-01-12
  • Comparative effects of Bisphenol S and Bisphenol A on the development of female reproductive system in rats; a neonatal exposure study
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Nida Ahsan, Hizb Ullah, Waheed Ullah, Sarwat Jahan

    Bisphenol A (BPA) has been well documented for its endocrine disrupting potential however, very little is known about endocrine disrupting abilities of bisphenol S (BPS). The present study aimed to compare the endocrine disrupting potentials of BPS with BPA, using female rats as an experimental animal model. On postnatal day 1 (PND 1) female pups born were randomly assigned to seven different treatments. Control group received subcutaneous injection of castor oil (50 μL) from PND 1 to PND 10. Three groups of female pups were injected subcutaneously with different concentrations (0.5, 5 and 50 mg/kg in 50 μL castor oil) of BPS, while remaining three groups were treated with 0.5, 5 and 50 mg/kg BPA. Highest doses treatments of both compounds resulted in delayed puberty onset and altered estrous cyclicity. Final body weight was significantly high in the highest dose treated groups of both BPS and BPA. Gonadosomatic index, absolute and relative weight of uteri was significantly reduced in BPS (5 and 50 mg/kg) and BPA (5 and 50 mg/kg) treated groups than control. Plasma concentrations of testosterone and estradiol were significantly increased, while plasma progesterone, Luteinizing hormone (LH) and Follicle stimulating hormone (FSH) concentrations were significantly reduced in highest doses treated groups. Dose dependent increase in the number of cystic follicles in the ovaries was evident along with an increase in the number of atratic follicles. The results suggest that neonatal exposure to higher concentrations of BPS can lead to BPA like structural and endocrine alterations in female rats.

    更新日期:2018-01-12
  • Photolysis mechanism of sulfonamide moiety in five-membered sulfonamides: A DFT study
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Pu Ge, Hang Yu, Jingwen Chen, Jingping Qu, Yi Luo
    更新日期:2018-01-12
  • pH-dependent roles of polycarboxylates in electron transfer between Cr(VI) and weak electron donors
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Bo Jiang, Haihong He, Yijie Liu, Yizhen Tang, Siyi Luo, Zhaohui Wang
    更新日期:2018-01-12
  • A novel method for synthesis of polyaniline and its application for catalytic degradation of atrazine in a Fenton-like system
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Chao Wang, Zupei Guo, Ran Hong, Juan Gao, Yong Guo, Cheng Gu
    更新日期:2018-01-12
  • Ecological and health risks assessment and spatial distribution of residual heavy metals in the soil of an e-waste circular economy park in Tianjin, China
    Chemosphere (IF 4.208) Pub Date : 2018-01-12
    Wei Han, Guanghai Gao, Jinyao Geng, Yao Li, Yingying Wang

    Ziya Circular Economy Park is the biggest e-waste recycle park in North China before 2011, its function was then transformed in response to regulations and rules. In this paper, investigation was conducted to research the residual concentrations of 14 analytes (12 heavy metals and 2 non-metals) in the surface soil of Ziya Circular Economy Park and surrounding area. Both ecological and health assessments were evaluated using GI (geo-accumulation index) and NPI (Nemerow pollution index), and associated health risk was assessed by using USEPA model. According to the ecological risk assessment, Cu, Sb, Cd, Zn and Co were seriously enriched in the soil of the studied area. The health risk assessment proposed by USEPA indicated no significant health risks to the population. Soil properties, such as pH and organic matter, were found to correlate with the enrichment of heavy metals. Arsenic concentrations in the soil were found positively correlated to dead bacteria concentrations. Spatial distribution of heavy metals revealed that Ziya Circular Economy Park was the dominant pollution source in the studied area. Findings in this study suggest that enough attention should be payed to the heavy metal pollution in Ziya Circular Economy Park.

    更新日期:2018-01-12
  • Ultrafiltration membrane fouling induced by humic acid with typical inorganic salts
    Chemosphere (IF 4.208) Pub Date : 2018-01-11
    Baiwen Ma, Yanyan Ding, Wenjiang Li, Chengzhi Hu, Min Yang, Huijuan Liu, Jiuhui Qu
    更新日期:2018-01-11
  • Identification of number and type of cations in water-soluble Cs+ and Na+ calix[4]arene-bis-crown-6 complexes by using ESI-TOF-MS
    Chemosphere (IF 4.208) Pub Date : 2018-01-11
    Shogo Kumagai, Kotaro Hayashi, Tomohito Kameda, Naoya Morohashi, Tetsutaro Hattori, Toshiaki Yoshioka
    更新日期:2018-01-11
  • Carotenoid and superoxide dismutase are the most effective antioxidants participating in ROS scavenging in phenanthrene accumulated wheat leaf
    Chemosphere (IF 4.208) Pub Date : 2018-01-11
    Yu Shen, Jinfeng Li, Ruochen Gu, Le Yue, Hongju Wang, Xinhua Zhan, Baoshan Xing

    Polycyclic aromatic hydrocarbons (PAHs) are a kind of pollutants which could stimulate stress reaction in plant cells. In this study, we systematically verify that PAHs could induce an oxidative stress in plants, and describe their damages on wheat leaf subcellular structure and organelle, together with the contributions of antioxidants working against reactive oxygen species. The observation of transmission electron microscope exhibits that cell structures become plasmolyzed and distorted, and organelles disappear under phenanthrene (a model PAH) treatments. Osmiophilic granules arise with increasing phenanthrene concentrations, displaying the evidence for oxidative stress. As more H2O2 produce, and the accumulation of H2O2 is a fatal reason for cell death under PAH treatments. Through cluster analysis, Pearson correlation coefficient, principal component analysis and redundancy analysis, carotenoid and superoxide dismutase are the two most effective antioxidants to scavenge superoxide radicals among nine major antioxidants (ascorbate, glutathione, polyamines, α-tocopherol, carotenoid, catalases, ascorbate peroxidase, superoxide dismutase and glutathione-S-transferase), glutathione-S-transferase is a potential antioxidant, and Asa-GSH cycle would turn active under higher phenanthrene treatments. Ascorbate peroxidase and α-tocopherol would lead leaf moisture increase. Thus, this work provides better comprehension on the antioxidant performances and their potential application to improving plants’ resistance under PAH pollution in the environment.

    更新日期:2018-01-11
  • Model-based assessment of estrogen removal by nitrifying activated sludge
    Chemosphere (IF 4.208) Pub Date : 2018-01-10
    Lai Peng, Xiaohu Dai, Yiwen Liu, Jing Sun, Shaoxian Song, Bing-Jie Ni
    更新日期:2018-01-11
  • Synthesis of graphene/SiO2@polypyrrole nanocomposites and their application for Cr(VI) removal in aqueous solution
    Chemosphere (IF 4.208) Pub Date : 2018-01-10
    Wei Fang, Xianying Jiang, Hanjin Luo, Junjie Geng
    更新日期:2018-01-10
  • Cost effectiveness of phosphorus removal processes in municipal wastewater treatment
    Chemosphere (IF 4.208) Pub Date : 2018-01-10
    Rania Bashar, Kerem Gungor, K.G. Karthikeyan, Phillip Barak

    Meeting stringent phosphorus (P) discharge standards remains one of the major challenges for wastewater utilities due to increased economic burdens associated with advanced (i.e., secondary, tertiary) treatment processes. In a trade-off between higher treatment cost and enhanced P removal, it is critical for the treatment plants to be able to select the most appropriate technology. To this end, established/emerging high performing P removal/recovery technologies (e.g., Modified University of Cape Towne process, Bardenpho process, membrane bioreactors, IFAS-EBPR, struvite recovery, tertiary reactive media filtration) were identified and full-scale treatment plant designs were developed. Using advanced mathematical modeling techniques, six different treatment configurations were evaluated in terms of performance and cost effectiveness ($/lb of P removed). Results show that the unit cost for P removal in different treatment alternatives range from $42.22 to $60.88 per lb of P removed. The MUCT BNR + tertiary reactive media filtration proved to be one of the most cost effective configurations ($44.04/lb P removed) delivering an effluent with total P (TP) concentration of only 0.05 mg/L. Although struvite recovery resulted in significant reduction in biosolids P, the decrease in effluent TP was not sufficient to meet very stringent discharge standards.

    更新日期:2018-01-10
  • Dermal uptake and percutaneous penetration of organophosphate esters in a human skin ex vivo model
    Chemosphere (IF 4.208) Pub Date : 2018-01-10
    Marie Frederiksen, Heather M. Stapleton, Katrin Vorkamp, Thomas F. Webster, Niels Martin Jensen, Jens Ahm Sørensen, Flemming Nielsen, Lisbeth E. Knudsen, Lars S. Sørensen, Per Axel Clausen, Jesper B. Nielsen
    更新日期:2018-01-10
  • 更新日期:2018-01-09
  • Method development for the analysis of ionophore antimicrobials in dairy manure to assess removal within a membrane-based treatment system
    Chemosphere (IF 4.208) Pub Date : 2018-01-09
    Jerod J. Hurst, Josh S. Wallace, Diana S. Aga

    Ionophore antimicrobials are heavily used in the livestock industries, both for preventing animal infection by coccidia protozoa and increasing feed efficiency. Ionophores are excreted mostly unmetabolized and are released into the environment when manure is land-applied to fertilize croplands. Here, an analytical method was optimized to study the occurrences of five ionophore residues (monensin, lasalocid, maduramycin, salinomycin, and narasin) in dairy manure after solid-liquid separation and further treatment of the liquid manure by a membrane-based treatment system. Ionophore residues from the separated solid manure (dewatered manure) and suspended solids of manure slurry samples were extracted using ultrasonication with methanol, followed by sample clean-up using solid phase extraction (SPE) and subsequent analysis via liquid chromatography-tandem mass spectrometry (LC-MS/MS). The use of an ethyl acetate and methanol (1:1 v:v) mixture as an SPE eluent resulted in higher recoveries and lower method quantitation limits (MQL), when compared to using methanol. Overall recoveries from separated solid manure ranged from 73 to 134%. Liquid manure fractions were diluted with Nanopure™ water and cleaned up using SPE, where recoveries ranged from 51 to 100%. The developed extraction and LC-MS/MS methods were applied to analyze dairy manure samples subjected to an advanced manure treatment process, involving a membrane-based filtration step (reverse osmosis). Monensin and lasalocid were detected at higher concentrations in the suspended solid fractions (4.40–420 ng/g for lasalocid and 85–1950 ng/g for monensin) compared to the liquid fractions (

    更新日期:2018-01-09
  • Characterization and release profile of (Mn, Al)-bearing deposits in drinking water distribution systems
    Chemosphere (IF 4.208) Pub Date : 2018-01-09
    Guiwei Li, Yuanxun Ding, Hongfu Xu, Junwei Jin, Baoyou Shi
    更新日期:2018-01-09
  • Depletion study, withdrawal period calculation and bioaccumulation of sulfamethazine in tilapia (Oreochromis niloticus) treated with medicated feed
    Chemosphere (IF 4.208) Pub Date : 2018-01-09
    Kátia S.D. Nunes, José H. Vallim, Márcia R. Assalin, Sonia C.N. Queiroz, Lourival C. Paraíba, Claudio M. Jonsson, Felix G.R. Reyes
    更新日期:2018-01-09
  • Combined effects of Ag and UiO-66 for removal of elemental mercury from flue gas
    Chemosphere (IF 4.208) Pub Date : 2018-01-09
    Songjian Zhao, Dongyao chen, Haomiao Xu, Jian mei, Zan Qu, Ping Liu, Yong Cui, Naiqiang Yan
    更新日期:2018-01-09
  • Highly effective catalytic peroxymonosulfate activation on N-doped mesoporous carbon for o-phenylphenol degradation
    Chemosphere (IF 4.208) Pub Date : 2018-01-09
    Jifei Hou, Shasha Yang, Haiqin Wan, Heyun Fu, Xiaolei Qu, Zhaoyi Xu, Shourong Zheng
    更新日期:2018-01-09
  • Effects of perinatal fluoride exposure on the expressions of miR-124 and miR-132 in hippocampus of mouse pups
    Chemosphere (IF 4.208) Pub Date : 2018-01-08
    Jixiang Wang, Yuliang Zhang, Zhenzhen Guo, Rui Li, Xingchen Xue, Zilong Sun, Ruiyan Niu
    更新日期:2018-01-09
  • Toxicokinetics of Zn and Cd in the earthworm Eisenia andrei exposed to metal-contaminated soils under different combinations of air temperature and soil moisture content
    Chemosphere (IF 4.208) Pub Date : 2018-01-08
    M. Nazaret González-Alcaraz, Susana Loureiro, Cornelis A.M. van Gestel

    This study evaluated how different combinations of air temperature (20 °C and 25 °C) and soil moisture content (50% and 30% of the soil water holding capacity, WHC), reflecting realistic climate change scenarios, affect the bioaccumulation kinetics of Zn and Cd in the earthworm Eisenia andrei. Earthworms were exposed for 21 d to two metal-contaminated soils (uptake phase), followed by 21 d incubation in non-contaminated soil (elimination phase). Body Zn and Cd concentrations were checked in time and metal uptake (k1) and elimination (k2) rate constants determined; metal bioaccumulation factor (BAF) was calculated as k1/k2. Earthworms showed extremely fast uptake and elimination of Zn, regardless of the exposure level. Climate conditions had no major impacts on the bioaccumulation kinetics of Zn, although a tendency towards lower k1 and k2 values was observed at 25 °C + 30% WHC. Earthworm Cd concentrations gradually increased with time upon exposure to metal-contaminated soils, especially at 50% WHC, and remained constant or slowly decreased following transfer to non-contaminated soil. Different combinations of air temperature and soil moisture content changed the bioaccumulation kinetics of Cd, leading to higher k1 and k2 values for earthworms incubated at 25 °C + 50% WHC and slower Cd kinetics at 25 °C + 30% WHC. This resulted in greater BAFs for Cd at warmer and drier environments which could imply higher toxicity risks but also of transfer of Cd within the food chain under the current global warming perspective.

    更新日期:2018-01-08
  • Carboxymethyl cellulose stabilized ZnO/biochar nanocomposites: Enhanced adsorption and inhibited photocatalytic degradation of methylene blue
    Chemosphere (IF 4.208) Pub Date : 2018-01-08
    Shengsen Wang, Yanxia Zhou, Shuwen Han, Nong Wang, Weiqin Yin, Xianqiang Yin, Bin Gao, Xiaozhi Wang, Jun Wang

    Biochar(BC)-supported nanoscaled zinc oxide (nZO) was encapsulated either with (nZORc/BC) or with no (nZOR/BC) sodium carboxymethyl cellulose (CMC). The X-ray diffraction and ultraviolet (UV)-visible-near infrared spectrophotometry revealed that nZO of 16, 10, and 20 nm with energy band gaps of 2.79, 3.68 and 2.62 eV were synthesized for nZOR/BC, nZORc/BC and nZO/BC, respectively. The Langmuir isotherm predicted saturated sorption of methylene blue (MB) was 17.01 g kg−1 for nZORc/BC, over 19 times greater than nZOR/BC and nZO/BC. Under UV irradiation, 10.9, 61.6, 83.1, and 41.6% of MB were degraded for nZORc/BC, nZO/BC, nZOR/BC and BC. The scavenging experiment revealed hydroxyl radical dominated CMC degradation. Exogenous CMC (2 g L−1) increased MB sorption from 10.6% to 73.1%, but decreased MB degradation from 80.7% to 41.1%, relative to nZOR/BC. Thus, CMC could increase MB sorption by electrostatic attraction and other possible mechanisms. The compromised MB degradation may be ascribed to reduced availability of hydroxyl and superoxide radicals to degrade MB, and increased band gap energy of ZnO.

    更新日期:2018-01-08
  • Geochemical sources of metal contamination in a coal mining area in Chhattisgarh, India using lead isotopic ratios
    Chemosphere (IF 4.208) Pub Date : 2018-01-08
    Avijit Das, Subhra Sarita Patel, Rajeev Kumar, K.V.S.S. Krishna, Saikat Dutta, Manik Chandra Saha, Siladitya Sengupta, Dipayan Guha
    更新日期:2018-01-08
  • PHBV polymer supported denitrification system efficiently treated high nitrate concentration wastewater: Denitrification performance, microbial community structure evolution and key denitrifying bacteria
    Chemosphere (IF 4.208) Pub Date : 2018-01-08
    Zhongshuo Xu, Liyan Song, Xiaohu Dai, Xiaoli Chai

    Biodegradable polymer supported denitrification (BPD) system shows good denitrification performance for the wastewater with low nitrate concentrations. In this study, a BPD system using Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) polymer as carbon source was developed to treat the wastewater with high nitrate concentrations. The denitrification performance, utilization ratio of PHBV polymers, and microbial community structure evolution and key denitrifying bacteria were comprehensively studied. Results indicated that an average nitrate removal efficiency of 99% could be achieved with an influent NO3−-N concentration of 100 mg L−1 and a hydraulic retention time (HRT) of 7.25 h. Mass balance model predicted that 80% of the PHBV polymers were consumed by denitrifying bacteria, close to 72% consumption in real condition, suggesting the model might be useful for PHBV polymers management in BPD system. Further, the bacterial community structures varied along the bioreactor profile, which closely linked to the concentration profiles of nitrate and ammonia. Metatranscriptomic analysis identified the key denitrifying bacteria as Comamonas, Acidovorax and Dechloromonas. The PHBV supported denitrification system developed in this study shows potential for removal of high concentration of nitrate from wastewater.

    更新日期:2018-01-08
  • 更新日期:2018-01-06
  • Bioremediation of cadmium- and zinc-contaminated soil using Rhodobacter sphaeroides
    Chemosphere (IF 4.208) Pub Date : 2018-01-06
    Weihua Peng, Xiaomin Li, Jingxiang Song, Wei Jiang, Yingying Liu, Wenhong Fan

    Bioremediation using microorganisms is a promising technique to remediate soil contaminated with heavy metals. In this study, Rhodobacter sphaeroides was used to bioremediate soils contaminated with cadmium (Cd) and zinc (Zn). The study found that the treatment reduced the overall bioavailable fractions (e.g., exchangeable and carbonate bound phases) of Cd and Zn. More stable fractions (e.g., Fe-Mn oxide, organic bound, and residual phases (only for Zn)) increased after bioremediation. A wheat seedling experiment revealed that the phytoavailability of Cd was reduced after bioremediation using R. sphaeroides. After bioremediation, the exchangeable phases of Cd and Zn in soil were reduced by as much as 30.7% and 100.0%, respectively; the Cd levels in wheat leaf and root were reduced by as much as 62.3% and 47.2%, respectively. However, when the soils were contaminated with very high levels of Cd and Zn (Cd 54.97–65.33 mg kg−1; Zn 813.4–964.8 mg kg−1), bioremediation effects were not clear. The study also found that R. sphaeroides bioremediation in soil can enhance the Zn/Cd ratio in the harvested wheat leaf and root overall. This indicates potentially favorable application in agronomic practice and biofortification. Although remediation efficiency in highly contaminated soil was not significant, R. sphaeroides may be potentially and practically applied to the bioremediation of soils co-contaminated by Cd and Zn.

    更新日期:2018-01-06
  • Partition of Zn, Cd, and Pb during co-combustion of sedum plumbizincicola and sewage sludge
    Chemosphere (IF 4.208) Pub Date : 2018-01-06
    Feihong Guo, Zhaoping Zhong, Hui Xue

    Co-combustion of sedum plumbizincicola and sewage sludge was performed in a tubular furnace. The influence of experimental conditions on the partitioning of Zn, Cd, and Pb was investigated. The results showed that 30% sewage sludge was proposed as the optimal ratio for the co-combustion as a compromise between low calorific value and high amount of heavy metal remained in the bottom ash. High temperature increased the volatilization degree of heavy metals, among which the performance of Cd and Pb was obvious than Zn. Rising oxygen concentration was beneficial to the formation of heavy metal compounds, and the effect of oxygen on Zn was the most pronounced. Thermodynamic equilibrium calculation was carried out to forecast heavy metal compounds. The results demonstrated that Zn, Cd, and Pb mainly generated ZnAl2O4, CdSiO3 and PbSiO3 in solid phase, which are partly confirmed by X-ray diffraction (XRD). The promising results offered a great possibility of heavy metal immobilization, indicating the combustion of Sedum plumbizincicola with sewage sludge is an effective way for waste disposal.

    更新日期:2018-01-06
  • Sources of polychlorinated dibenzo-p-dioxins and dibenzofurans, and biphenyls in Chinese mitten crabs
    Chemosphere (IF 4.208) Pub Date : 2018-01-06
    Ying Han, Wenbin Liu, Wen Zhu, Kaifeng Rao, Ke Xiao, Lirong Gao, Guijin Su, Guorui Liu

    Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) in Chinese mitten crabs from several areas were determined. The toxic equivalents (TEQs) for the mean PCDD/F and total PCDD/F and dioxin-like PCBs were 2.9 ± 2.7 and 5.7 ± 4.0 pg TEQ g−1, respectively. The mean concentrations of PCBs and dl-PCBs were 282 and 59 times the concentrations of PCDD/Fs, respectively. PCDD/F and PCB sources in the crab food web were assessed. The total TEQ of PCDD/F and PCB supplied by crab compound feed was 2.1 times the TEQ in crab meat. Broken corn, aquatic biota, and water contributed around 12% of the total TEQ inputs for crab meat. The contribution from sediment was around 164 times that from crab meat, and sediment may be the most important source of PCDD/Fs and PCBs in cultured crabs. Principal component analysis (PCA) and stable isotope ratios for nitrogen (δ15N) and carbon (δ13C) supported the TEQ results. The mean total PCDD/F and dl-PCB TEQ exposure for humans consuming crabs was 3.4 pg TEQ per kilogram of body weight per day. The PCDD/Fs and PCBs in >80% of the crab samples would not cause the tolerable daily intake to be exceeded.

    更新日期:2018-01-06
  • Feedback mechanisms between snow and atmospheric mercury: Results and observations from field campaigns on the Antarctic plateau
    Chemosphere (IF 4.208) Pub Date : 2018-01-05
    Andrea Spolaor, Hélène Angot, Marco Roman, Aurélien Dommergue, Claudio Scarchilli, Massimiliano Vardè, Massimo Del Guasta, Xanthi Pedeli, Cristiano Varin, Francesca Sprovieri, Olivier Magand, Michel Legrand, Carlo Barbante, Warren R.L. Cairns
    更新日期:2018-01-06
  • Presence of Fe-Al binary oxide adsorbent cake layer in ceramic membrane filtration and their impact for removal of HA and BSA
    Chemosphere (IF 4.208) Pub Date : 2018-01-05
    Kyung-Jo Kim, Am Jang

    To enhance the removal of natural organic matter (NOM) in ceramic (Ce) membrane filtration, an iron-aluminum binary oxide (FAO) was applied to the ceramic membrane surface as the adsorbent cake layer, and it was compared with heated aluminum oxide (HAO) for the evaluation of the control of NOM. Both the HAO and FAO adsorbent cake layers efficiently removed the NOM regardless of NOM's hydrophobic/hydrophilic characteristics, and the dissolved organic carbon (DOC) removal in NOM for FAO was 1–1.12 times greater than that for HAO, which means FAO was more efficient in the removal of DOC in NOM. FAO (0.03 μm), which is smaller in size than HAO (0.4 μm), had greater flux reduction than HAO. The flux reduction increased as the filtration proceeded because most of the organic foulants (colloid/particles and soluble NOM) were captured by the adsorbent cake layer, which caused fouling between the membrane surface and the adsorbent cake layer. However, no chemically irreversible fouling was observed on the Ce membrane at the end of the FAO adsorbent cake layer filtration. This means that a stable adsorbent cake layer by FAO formed on the Ce membrane, and that the reduced pure water flux of the Ce membrane, resulting from the NOM fouling, can easily be recovered through physicochemical cleaning.

    更新日期:2018-01-06
  • Electrochemical and microbial community responses of electrochemically active biofilms to copper ions in bioelectrochemical systems
    Chemosphere (IF 4.208) Pub Date : 2018-01-05
    Yaping Zhang, Guanqun Li, Jing Wen, Yangao Xu, Jian Sun, Xun-an Ning, Xingwen Lu, Yujie Wang, Zuoyi Yang, Yong Yuan
    更新日期:2018-01-05
  • The influence of algal organic matter produced by Microcystis aeruginosa on coagulation-ultrafiltration treatment of natural organic matter
    Chemosphere (IF 4.208) Pub Date : 2018-01-05
    Jie Xu, Yanxia Zhao, Baoyu Gao, Songlin Han, Qian Zhao, Xiaoli Liu
    更新日期:2018-01-05
  • Inhibition of UDP-glucuronosyltransferases (UGTs) by phthalate monoesters
    Chemosphere (IF 4.208) Pub Date : 2018-01-05
    Zuo Du, Yun-Feng Cao, Sai-Nan Li, Cui-Min Hu, Zhi-Wei Fu, Chun-Ting Huang, Xiao-Yu Sun, Yong-Zhe Liu, Kun Yang, Zhong-Ze Fang
    更新日期:2018-01-05
  • Lithium as an emerging environmental contaminant: mobility in the soil-plant system
    Chemosphere (IF 4.208) Pub Date : 2018-01-05
    Brett H. Robinson, Rohith Yalamanchali, René Reiser, Nicholas M. Dickinson

    Contamination of soil with lithium (Li) is likely to increase due to its wider dispersal in the environment, associated in particular, with the disposal of the now ubiquitous Li-ion batteries. There is, however, a paucity of information on the behaviour of Li in the soil-plant system. We measured the sorption of added Li to soil, and uptake of Li by food and fodder species. Around New Zealand, soil concentrations were shown to range from 0.08 mg/kg to 92 mg/kg, and to be positively correlated with clay content. Most geogenic Li in soil is insoluble and hence unavailable to plants but, when Li+ is added to soil, there is only limited sorption of Li. We found that Li sorption increased with increasing soil pH, and decreased proportionately with increasing Li concentrations. Compared to other cations in soil, Li is mobile and may leach into receiving waters, be taken up by plants, or have other biological impacts. In a soil spiked with just 5 mg/kg, plants took up several hundred mg/kg Li into leaves with no reduction in biomass. Lithium appears to be a phloem immobile element, with the highest concentrations occurring in the older leaves and the lowest concentrations occurring in the seeds or fruits. These results may raise concerns and risks in situations where food and fodder crops are associated with waste disposal.

    更新日期:2018-01-05
  • Element mobilization and immobilization from carbonate rocks between CO2 storage reservoirs and the overlying aquifers during a potential CO2 leakage
    Chemosphere (IF 4.208) Pub Date : 2018-01-04
    Amanda R. Lawter, Nikolla P. Qafoku, R. Matthew Asmussen, Ravi K. Kukkadapu, Odeta Qafoku, Diana H. Bacon, Christopher F. Brown
    更新日期:2018-01-05
  • In vitro dermal bioaccessibility of selected metals in contaminated soil and mine tailings and human health risk characterization
    Chemosphere (IF 4.208) Pub Date : 2018-01-04
    Laura T. Chaparro Leal, Mert Guney, Gerald J. Zagury

    Dermal exposure to contaminated sites has generally received less attention than oral/inhalation exposure due to limited exposure scenarios and less perceived potential for toxicity, however, the risk can be significant for specific contaminants and scenarios. The present study aims to (1) measure Cr, Ni, Pb, and Zn contamination in soil and mine tailings samples (n = 7), (2) determine the dermal bioaccessibility of these metals via in vitro tests using two synthetic sweat formulations (EN, 1811; NIHS 96-10), and (3) obtain dermal absorbed doses (DADs) for children's and adults' exposure scenarios and compare them to derived dermal reference values. The NIHS 96-10 formulation yielded higher bioaccessibility values for all metals than EN 1811, possibly due to its lower pH. Zn had the highest bioaccessibility for both formulations whereas Cr had the lowest. There was some evidence of adsorption of initially mobilized Pb and Zn to soil with longer test times, resulting in slightly lower bioaccessibility after 8 h of testing with respect to 2 h. The calculated DADs showed that the risk for exposure was acceptable (DAD < derived dermal reference value) for all metals except for Cr(VI) considering exposure to two of the samples. The risk in the case of children's exposure scenario (play on contaminated medium) was significantly higher than the case for the adults' exposure scenario (exposure in industrial context). Additional bioaccessibility research is recommended on additional samples with differing properties/contamination profiles, on additional contaminants with high dermal affinity (especially As), and on the development/validation of in vitro dermal bioaccessibility tests.

    更新日期:2018-01-04
  • A label-free electrochemical system for comprehensive monitoring of o-chlorophenol
    Chemosphere (IF 4.208) Pub Date : 2018-01-04
    Xiaolin Zhu, Kexin Zhang, Nan Lu, Yangyang Yu, Xing Yuan, Jiunian Guan

    o-Chlorophenol (OCP) is a priority pollutant that poses serious health threats to the public. The following study designs a simple electrochemical system to monitor the concentration and toxicity of OCP. This system was primarily characterized by the integration of both physicochemical and biological monitoring procedures that had a synergistic effect between the functionalized carbon nanotubes and rhodamine B. This resulted in excellent electrocatalytic activities toward OCP and cellular purine bases. The peak current of OCP was linear with concentrations ranging from 0.05–125.0 μM and the detection limit was 0.028 μM under optimal testing conditions. There was an enhanced voltammetric signal detected that was caused by the guanine/xanthine of human hepatoma (HepG2) cells. The cytotoxicity of OCP to HepG2 cells was assessed using the proposed system. The obtained IC50 value was 512.86 μM. This study provided a fast, label-free, and low-cost platform for the comprehensive assessment of OCP. This is highly beneficial for simplifying the environmental monitoring process.

    更新日期:2018-01-04
  • Gas/particle partitioning, particle-size distribution of atmospheric polybrominated diphenyl ethers in southeast Shanghai rural area and size-resolved predicting model
    Chemosphere (IF 4.208) Pub Date : 2018-01-04
    Peng-hao Su, Gregg T. Tomy, Chun-yan Hou, Fang Yin, Dao-lun Feng, Yong-sheng Ding, Yi-fan Li

    A size-segregated gas/particle partitioning coefficient KPi was proposed and evaluated in the predicting models on the basis of atmospheric polybrominated diphenyl ether (PBDE) field data comparing with the bulk coefficient KP. Results revealed that the characteristics of atmospheric PBDEs in southeast Shanghai rural area were generally consistent with previous investigations, suggesting that this investigation was representative to the present pollution status of atmospheric PBDEs. KPi was generally greater than bulk KP, indicating an overestimate of TSP (the mass concentration of total suspended particles) in the expression of bulk KP. In predicting models, KPi led to a significant shift in regression lines as compared to KP, thus it should be more cautious to investigate sorption mechanisms using the regression lines. The differences between the performances of KPi and KP were helpful to explain some phenomenon in predicting investigations, such as Po Land KOA models overestimate the particle fractions of PBDEs and the models work better at high temperature than at low temperature. Our findings are important because they enabled an insight into the influence of particle size on predicting models.

    更新日期:2018-01-04
  • Metal sorption to Spodosol Bs horizons: Organic matter complexes predominate
    Chemosphere (IF 4.208) Pub Date : 2018-01-04
    Charlotta Tiberg, Carin Sjöstedt, Jon Petter Gustafsson
    更新日期:2018-01-04
  • Adsorption dynamics and mechanism of aqueous sulfachloropyridazine and analogues using the root powder of recyclable long-root Eichhornia crassipes
    Chemosphere (IF 4.208) Pub Date : 2018-01-03
    Lin Liu, Shuangqing Hu, Genxiang Shen, Usman Farooq, Wei Zhang, Sen Lin, Kuangfei Lin
    更新日期:2018-01-04
  • Ranking and similarity of conventional, microwave and ultrasound element sequential extraction methods
    Chemosphere (IF 4.208) Pub Date : 2018-01-03
    Dubravka Relić, Károly Héberger, Sanja Sakan, Biljana Škrbić, Aleksandar Popović, Dragana Đorđević
    更新日期:2018-01-03
  • An overview on the removal of synthetic dyes from water by electrochemical advanced oxidation processes
    Chemosphere (IF 4.208) Pub Date : 2018-01-03
    P.V. Nidheesh, Minghua Zhou, Mehmet A. Oturan

    Wastewater containing dyes are one of the major threats to our environment. Conventional methods are insufficient for the removal of these persistent organic pollutants. Recently much attention has been received for the oxidative removal of various organic pollutants by electrochemically generated hydroxyl radical. This review article aims to provide the recent trends in the field of various Electrochemical Advanced Oxidation Processes (EAOPs) used for removing dyes from water medium. The characteristics, fundamentals and recent advances in each processes namely anodic oxidation, electro-Fenton, peroxicoagulation, fered Fenton, anodic Fenton, photoelectro-Fenton, sonoelectro-Fenton, bioelectro-Fenton etc. have been examined in detail. These processes have great potential to destroy persistent organic pollutants in aqueous medium and most of the studies reported complete removal of dyes from water. The great capacity of these processes indicates that EAOPs constitute a promising technology for the treatment of the dye contaminated effluents.

    更新日期:2018-01-03
  • Effects of the addition and aging of humic acid-based amendments on the solubility of Cd in soil solution and its accumulation in rice
    Chemosphere (IF 4.208) Pub Date : 2018-01-02
    Yao Yu, Yanan Wan, Aboubacar Younoussa Camara, Huafen Li

    Humic substances can reduce mobility and bio-accessibility of Cd in soil and therefore inhibit its uptake by rice, which is a major source of human Cd intake. Yet, the effects of aging humic substances are not fully understood. A rice pot experiment was conducted to evaluate the effects of humic acid-based amendments on the mobility of Cd in soil solution and its uptake by rice when amendments were freshly added or aged for 130 d. The results showed that the aged and the unaged amendments generally decreased Cd concentration in soil solution, but the effect declined with time. Unaged HA-K (humic-potassium) reduced Cd concentration by 88% for the first sampling, but this dropped to 46% for the last sampling, compared to that of the control. All amendments, whether aged or not, reduced the content of Cd in rice seedlings, as well as in mature plants. Aged and unaged woody peat reduced the Cd content in seedlings by 79% and in grains by 70%, respectively. Aging of amendments caused lower pH and higher Cd concentration in the soil solution for all amendments and accordingly, the Cd content in rice seedlings or each part of mature plants in the aged group was higher than that of the unaged group. The applied amendments might reduce the solubility of Cd through the alteration in soil pH, and thus inhibit the uptake of Cd by rice, but the effects diminished with aging.

    更新日期:2018-01-03
  • The interaction of trace heavy metal with lipid monolayer in the sea surface microlayer
    Chemosphere (IF 4.208) Pub Date : 2018-01-02
    Siyang Li, Lin Du, Narcisse T. Tsona, Wenxing Wang
    更新日期:2018-01-03
  • The secretion of organics by living Microcystis under the dark/anoxic condition and its enhancing effect on nitrate removal
    Chemosphere (IF 4.208) Pub Date : 2018-01-02
    Xuechu Chen, Yingying Huang, Guiqin Chen, Panpan Li, Yingshi Shen, Timothy Walter Davis
    更新日期:2018-01-02
  • Biochar-based functional materials in the purification of agricultural wastewater: Fabrication, application and future research needs
    Chemosphere (IF 4.208) Pub Date : 2018-01-02
    Dongning Wei, Bingyu Li, Hongli Huang, Lin Luo, Jiachao Zhang, Yuan Yang, Jiajun Guo, Lin Tang, Guangming Zeng, Yaoyu Zhou
    更新日期:2018-01-02
  • A glyphosate-based herbicide reduces fertility, embryonic upper thermal tolerance and alters embryonic diapause of the threatened annual fish Austrolebias nigrofasciatus
    Chemosphere (IF 4.208) Pub Date : 2018-01-02
    Yuri Dornelles Zebral, Luize Real Lansini, Patrícia Gomes Costa, Mauricio Roza, Adalto Bianchini, Ricardo Berteaux Robaldo

    Roundup is the most popular glyphosate-based herbicide (GBH) worldwide. These formulations kill a wide range of plants. Despite that, non-target species can be jeopardized by GBH, such as the annual fish Austrolebias nigrofasciatus. This species occurs in wetlands that dries annually. key-adaptations permit them to live in such harsh habitats, e.i. elevated fertility, drought-tolerant diapausing embryos and elevated thermal tolerance. We aimed to evaluate acute (96 h) effects of Roundup exposure (0.36 or 3.62 mg a.e./L) in reproduction, diapause pattern and embryonic upper thermal tolerance (EUTT) of A. nigrofasciatus. For such, we evaluated the number and diameter of embryos produced by exposed fish. Also, recently fertilized embryos were exposed and its diapause pattern was evaluated. Following 15 post exposure days (PED), we evaluated the number of somite pairs and following 30, 35 and 40 PED we evaluated the proportion of pigmented embryos (PPE). Finally, the critical thermal maximum (CTMax) of exposed embryos was assessed. Results demonstrated that couples exposed to 0.36 mg a.e./L Roundup produced less but larger embryos. Similarly, embryos exposed to 3.62 mg a.e./L Roundup had a reduced PPE following 30 PED. Finally, embryos exposed to 0.32 mg a.e./L Roundup had a CTMax reduction of 2.6 oC and were more sensitive to minor increases in heating rates. These results indicate that Roundup have negative outcomes in fish reproduction, embryonic development and EUTT. This information is of particular interest to the conservation of annual fish, considering that those are key-adaptations that permit these animals to survive the harsh impositions of ephemeral wetlands.

    更新日期:2018-01-02
  • Bioaccumulation of Heavy Metals in Maricultured Fish, Lates calcarifer (Barramudi), Lutjanus campechanus (Red Snapper) and Lutjanus griseus (Grey Snapper)
    Chemosphere (IF 4.208) Pub Date : 2018-01-02
    Nor Nasyitah Sobihah Nasri, Ahmad Zaharin Aris, Khairul Nizam Mohammad, Ley Juen Looi, Kyoung-Woong Kim

    Mariculture fish contains a rich source of protein, but some species may bioaccumulate high levels of heavy metals, making them unsafe for consumption. This study aims to identify heavy metal concentration in Lates calcarifer (Barramudi), Lutjanus campechanus (Red snapper) and Lutjanus griseus (Grey snapper). Three species of mariculture fish, namely, L. calcarifer, L. campechanus and L. griseus were collected for analyses of heavy metals. The concentration of heavy metal (As, Cd, Cu, Cr, Fe, Pb, Mn, Ni, Se, and Zn) was determined using inductive coupled plasma mass spectrometry (ICP-MS). The distribution of heavy metals mean concentration in muscle is Zn > Fe > As > Se > Cr > Cu > Mn > Pb > Ni > Cd for L. calcarifer, Fe > Zn > Cr > As > Ni > Mn > Se > Cu > Pb > Cd for L. campechanus and Fe > Zn > Cr > Ni > Se > Cu > As > Mn >Pb > Cd for L. griseus. Among all of the species under investigation, the highest concentration of Fe was found in the muscle tissue of L. campechanus (19.985 ± 1.773 mg.kg-1) and liver tissue of L. calcarifer (0.007 ± 0.004 mg.kg-1). Meanwhile, L. calcarifer has the lowest concentration of Cd in both muscle (0.007 ± 0.004 mg.kg-1) and liver tissue (0.027 ± 0.016 mg.kg-1). The heavy metal concentration in muscle tissue is below the permissible limit guidelines stipulated by the Food & Agriculture Organization and Malaysia Food Act, 1983. The concentration of heavy metals varies significantly among fish species and tissues. L. campechanus was found to have a higher ability to accumulate heavy metals as compared to the other two species (p < 0.00). Among all the studied fish, liver tissue has a higher concentration of heavy metals compared to muscle tissue (p < 0.05). The findings from this study can serve as baseline information for future monitoring and risk assessment studies. Periodic monitoring of heavy metal concentration in mariculture fish must be performed to prevent acute and chronic food intoxication.

    更新日期:2018-01-02
  • 更新日期:2018-01-02
  • Mechanisms of biochar reducing the bioaccumulation of PAHs in rice from soil: Degradation stimulation vs immobilization
    Chemosphere (IF 4.208) Pub Date : 2018-01-02
    Ni Ni, Fang Wang, Yang Song, Yongrong Bian, Renyong Shi, Xinglun Yang, Chenggang Gu, Xin Jiang
    更新日期:2018-01-02
  • Reinvestigating the role of reactive species in the oxidation of organic co-contaminants during Cr(VI) reactions with sulfite
    Chemosphere (IF 4.208) Pub Date : 2017-12-30
    Hongyu Dong, Guangfeng Wei, Wenjuan Fan, Shangchen Ma, Hongying Zhao, Weixian Zhang, Xiaohong Guan, Timothy J. Strathmann

    Experimental work was undertaken in this study to re-investigate the mechanisms and active species responsible for oxidation of co-contaminants in the Cr(VI)/HSO3− reaction system. Batch experiments showed that the degradation rates of 4-chlorophenol (4-CP) correlated well with the rates of Cr(VI) reduction by sulfite in the same solutions, and that O2(aq) was necessary for the oxidation of 4-CP. Multiple lines of evidences indicate that Cr(VI)/HSO3− reaction is a SO4 radical dot −-based oxidation process. SO3 radical dot − was generated in Cr(VI)/HSO3− system based on the electron spin resonance spectra, which could be transformed to secondary radicals (SO4 radical dot −, SO5 radical dot −, and HO radical dot ). The contribution of SO5 radical dot − was ruled out through almost complete inhibition of methanol (MeOH) on 4-CP degradation. Considering the negligible inhibition of tert-butanol (TBA) on 4-CP degradation, SO4 radical dot − was identified to be reactive species in Cr(VI)/HSO3− process. This result was further verified by almost no degradation of nitrobenzene and the inhibiting effect of Cl− in Cr(VI)/HSO3− process. This mechanism is beneficial to application of Cr(VI)/HSO3− system in wastewater treatment.

    更新日期:2017-12-31
  • Kinetic Studies of the AOP Radical-Based Oxidative and Reductive Destruction of Pesticides and Model Compounds in Water
    Chemosphere (IF 4.208) Pub Date : 2017-12-30
    Kristin K. Clark, Stephen P. Mezyk, Amberashley Abbott-Hearn, James J. Kiddle

    Absolute second-order rate constants for hydroxyl radical (HO●) reaction with four organophosphorus pesticides, malathion, parathion, fenthion and ethion, and a suite of model compounds of structure (EtO)2P(S)-X (where X = Cl, F, SH, SEt, OCH2CF3, OEt, NH2, and CH3) were measured using electron pulse radiolysis and transient absorption techniques. Specific values were determined for these four pesticides as k = (3.89 ± 0.28) x 109, (2.20 ± 0.15) x 109, (2.02 ± 0.15) x 109 and (2.93 ± 0.10) x 109 M-1 s-1, respectively, at 20 ± 2oC. The corresponding Brönsted plot for all these compounds demonstrated that the HO● oxidation reaction mechanism for the pesticides was consistent with the model compounds, attributed to initial HO●-adduct formation at the P(S) moiety. For malathion, steady-state 60Co radiolysis and 31P NMR analyses showed that hydroxyl radical-induced oxidation produces the far more potent isomalathion, but only with an efficiency of 4.9 ± 0.3%. Analogous kinetic measurements for the hydrated electron induced reduction of these pesticides gave specific rate constants of k = (3.38 ± 0.14) x 109, (1.38 ± 0.10) x 109, (1.19 ± 0.12) x 109 and (1.20 ± 0.06) x 109 M-1 s-1, respectively, for malathion, parathion, fenthion and ethion. Model compound measurements again supported a single reduction reaction mechanism, proposed to be electron addition at the P=S bond to form the radical anion. These results demonstrate, for the first time, that the radical-based treatment of organophosphorus contaminated waters may present a potential toxicological risk if advanced oxidative processes are used.

    更新日期:2017-12-31
  • Effect of Exogenous Phosphate on the Lability and Phytoavailability of Arsenic in Soils
    Chemosphere (IF 4.208) Pub Date : 2017-12-30
    Jinjin Wang, Xibai Zeng, Hao Zhang, Yongtao Li, Shizhen Zhao, Shiming Su, Lingyu Bai, Yanan Wang, Tuo Zhang

    The effect of exogenous phosphate (P, 200 mg·kg-1 soil) on the lability and phyto-availability of arsenic (As) was studied using the diffusive gradients in thin films (DGT) technique. Lettuce were grown on the As-amended soils following the stabilization of soil labile As after 90 day’s incubation. Phosphate (P) application generally facilitated plant growth except one grown on P-sufficient soil. Soil labile As concentration increased in all the soils after P application due to a competition effect. Plant As concentration increased in red soils collected from Hunan Province, while decreases were observed in the other soils. Even though, an overall trend of decrease was obtained in As phytoavailability along with the increase of DGT-measured soil labile P/As molar ratio. The functional equation between P/As and As phytoavailability provided a critical value of 1.7, which could be used as a guidance for rational P fertilization, thus avoiding overfertilization.

    更新日期:2017-12-31
  • Metal complexation capacity of Antarctic lacustrine sediments
    Chemosphere (IF 4.208) Pub Date : 2017-12-30
    Giancarla Alberti, Matteo Mussi, Federico Quattrini, Maria Pesavento, Raffaela Biesuz
    更新日期:2017-12-31
Some contents have been Reproduced with permission of the American Chemical Society.
Some contents have been Reproduced by permission of The Royal Society of Chemistry.
化学 • 材料 期刊列表