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1.
A deltamethrin-imprinted polymer (MIP1) was prepared using bis(-6-O-butanediacid monoester)-β-cyclodextrin (BBA-β-CD) as the functional monomer and toluene 2,4-diisocyanate (TDI) as the cross-linker. In comparison to the molecularly imprinted polymer where β-CD was applied as the functional monomer (MIP2), MIP1 showed a higher specific binding capacity (ΔCP) and an improved imprinting factor (IF) for deltamethrin. The selective recognition experiments demonstrated that compared to MIP2, MIP1 could better recognize its template over other substrates that had similar chemical structures. The solid phase extraction (SPE) of deltamethrin using MIP1 as the adsorbent was further investigated. The recoveries of the molecularly imprinted solid phase extraction (MISPE) column for deltamethrin were 83.2–93.4% with relative standard deviations (RSD) of 2.03–6.19%. The method has been successfully applied to the enrichment of trace deltamethrin from real water samples.  相似文献   

2.
Abstract

The developed thin‐layer chromatogram of DCPA (Dacthal) is sprayed with 4‐(p‐nitrobenzyl)pyridine chromogenic reagent followed by ammonium carbonate solution. The chromatogram is then heated in an oven at 130°C for 20 minutes. When cool, the chromatogram is sprayed with tetraethylenepentamine reagent. DCPA spots appear blue against a white background. The sensitivity of this test is about 1 μg. The procedure is useful to detect DCPA in water and in soil.  相似文献   

3.
Sugarcane bagasse and hydroponic lettuce roots were used as biosorbents for Cu(II), Fe(II), Zn(II), and Mn(II) removal from monoelemental solutions in aqueous medium, at pH 5.5, using batch procedures. These biomasses were studied in natura (lettuce roots, NLR, and sugarcane bagasse, NSB) and modified with HNO3 (lettuce roots, MLR, and sugarcane bagasse, MSB). Langmuir, Freundlich, and Dubinin-Radushkevich non-linear isotherm models were used to evaluate the data from the metal ion adsorption assessment. The maximum adsorption capacities (qmax) in monoelemental solution, calculated using the Langmuir isothermal model for Cu(II), Fe(II), Zn(II), and Mn(II), were respectively 24.61, 2.64, 23.04, and 5.92 mg/g for NLR; 2.29, 16.89, 1.97, and 2.88 mg/g for MLR; 0.81, 0.06, 0.83, and 0.46 mg/g for NSB; and 1.35, 2.89, 20.76, and 1.56 mg/g for MSB. The Freundlich n parameter indicated that the adsorption process was favorable for Cu(II) uptake by NLR; Fe(II) retention by MLR and MSB; and Zn(II) sorption by NSB, MLR, and NSB and favorable for all biomasses in the accumulation of Mn(II). The Dubinin-Radushkevich isotherm was applied to estimate the energy (E) and type of adsorption process involved, which was found to be a physical one between analytes and adsorbents. Organic groups such as O–H, C–O–C, CH, and C=O were found in the characterization of the biomass by FTIR. In the determination of the biomass surface charges by using blue methylene and red amaranth dyes, there was a predominance of negative charges.  相似文献   

4.
Environmental Science and Pollution Research - This study firstly aimed to investigate the potential of simultaneous metal (loid) removal from metal (oid) solution through adsorption on iron-peat,...  相似文献   

5.

Ingredients in home and personal care products, including UV filters and benzotriazoles, are high production volume chemicals extensively used in our daily life, despite several studies revealed their potential eco-toxicity and endocrine-disrupting capacity. Due to some features, such as high lipophilicity, low degradability, and persistence of many of these compounds, sediments can be considered a sink for them in the aquatic environment. In the present study, nine organic UV filters and three benzotriazoles were investigated for the first time in sediments from four urban rivers in Brazil. The contaminants were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results revealed that octocrylene (OC), etylhexyl-methoxycinnamate (EHMC), benzophenone-3 (oxybenzone, BP3), and benzotriazole (BZT) were the predominant compounds adsorbed on the sediments, with concentrations ranging from 5.6 to 322.2 ng g−1 dry weight. The results reported in this work constitute the first data on the accumulation of polar benzotriazoles and lipophilic organic UV filters in sediments from Brazil.

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6.
Environmental Science and Pollution Research - The aim of this work was to develop a novel method for the preparation of structured Co–Mn mixed oxide catalysts: deposition on stainless steel...  相似文献   

7.
The relationship between bioaccumulation of heavy metals (Zn, Cd, Pb and Cu) and histological lesions in different tissues of organisms is assessed in three different areas located in the southwest of Spain in the Gulf of Cádiz (Ría of Huelva, Guadalquivir estuary and Bay of Cádiz) affected and non-affected by mining activities. Data included in these relationships were obtained along the years 2000 and 2001 to address the impact of the Aznalcóllar mining spill on the Guadalquivir estuary. The bioaccumulation and the histological lesions measured in this seasonal study in the Gudalquivir estuary were linked to derive tissue quality guidelines (TQGs) by means of a multivariate analysis approach (MAA). Sediments collected in the same areas of study were used to expose organisms during the survey carried out in autumn 2001 and to address the relationship between bioaccumulation and histological lesions under laboratory conditions and related to chemicals bound to sediments. Lesions show that the organisms collected in the ría of Huelva and exposed to their sediments were severe, intermediate in the Guadalquivir estuary and absent in the Bay of Cádiz. Results show that the Guadalquivir estuary trends to recover its initial status quo previous to the mining spill. The link between chemical concentration and the lesions measured in the same tissues using MAA permits to derive tissue quality guidelines for two organisms, oysters (Crassostrea angulata) and clams (Scrobicularia plana) collected in the Guadalquivir estuary and associated with the heavy metals from the mining spill (Zn and Cd). The TQG values expressed as concentrations (mgkg-1--dry weight) not associated with biological effects are for oysters, Zn, 8603, Cd, 3.42; and for clams Zn, 800, Cd, 2.6.  相似文献   

8.
The present study was conducted to investigate the anaerobic biodegradation potential of biostimulation by nitrate (KNO3) and methyl-β-cyclodextrin (MCD) addition on an aged organochlorine pesticide (OCP)-contaminated paddy soil. After 180 days of incubation, total OCP biodegradation was highest in soil receiving the addition of nitrate and MCD simultaneously and then followed by nitrate addition, MCD addition, and control. The highest biodegradation of chlordanes, hexachlorocyclohexanes, endosulfans, and total OCPs was 74.3, 63.5, 51.2, and 65.1 %, respectively. Meanwhile, MCD addition significantly increased OCP bioaccessibility (p?<?0.05) evaluated by Tenax TA extraction and a three-compartment model method. Moreover, the addition of nitrate and MCD also obtained the highest values of soil microbial activities, including soil microbial biomass carbon and nitrogen, ATP production, denitrifying bacteria count, and nitrate reductase activity. Such similar trend between OCP biodegradation and soil-denitrifying activities suggests a close relationship between OCP biodegradation and N cycling and the indirect/direct involvement of soil microorganisms, especially denitrifying microorganisms in the anaerobic biodegradation of OCPs.  相似文献   

9.
ABSTRACT

To evaluate the validity of fixed-site fine particle levels as exposure surrogates in air pollution epidemiology, we considered four indicator groups: (1) PM25 total mass concentrations, (2) sulfur and potassium for regional air pollution, (3) lead and bromine for traffic-related particles, and (4) calcium for crustal particles. Using data from the European EXPOLIS (Air Pollution Exposure Distribution within Adult Urban Populations in Europe) study, we assessed the associations between 48-hr personal exposures and home outdoor levels of the indicators. Furthermore, within-city variability of fine particle levels was evaluated.

Personal exposures to PM2.5 mass were not correlated to corresponding home outdoor levels (n = 44, rS (S) =r o v ' Spearman (Sp) 0.07). In the group reporting neither relevant indoor sources nor relevant activities, personal exposures and home outdoor levels of sulfur were highly correlated (n = 40, rSp = 0.85). In contrast, the associations were weaker for traffic (Pb: n = 44, rSp = 0.53; Br: n = 44, rSp = 0.21) and crustal (Ca: n = 44, rSp = 0.12) indicators. This contrast is consistent with spatially homogeneous regional pollution and higher spatial variability of traffic and crustal indicators observed in Basel, Switzerland.

We conclude that for regional air pollution, fixed-site fine particle levels are valid exposure surrogates. For source-specific exposures, however, fixed-site data are probably not the optimal measure. Still, in air pollution epidemiology, ambient PM2.5 levels may be more appropriate exposure estimates than total personal PM2.5 exposure, since the latter reflects a mixture of indoor and outdoor sources.  相似文献   

10.
The paper describes the fieldwork at the Italian test site of the abandoned mine of sphalerite and galena in Ingurtosu (Sardinia), with the aim to assess the applicability of a “toolbox” to establish the optimized techniques for remediation of soils contaminated by mining activities. A preliminary characterization—including (hydro)geochemistry, heavy metal concentration and their mobility in soil, bioprospecting for microbiology and botany—provided a data set for the development of a toolbox to deliver a microbially assisted phytoremediation process. Euphorbia pithyusa was selected as an endemic pioneer plant to be associated with a bacterial consortium, established with ten selected native strains, including metal-tolerant bacteria and producers of plant growth factors. The toolbox was firstly assessed in a greenhouse pot experiment. A positive effect of bacterial inoculum on E. pithyusa germination and total plant survival was observed. E. pithyusa showed to be a well-performing metallophyte species, and only inoculated soil retained a microbial activity with a high functional diversity, expanding metabolic affinity also towards root exudates. These results supported the decision to proceed with a field trial, investigating different treatments used singly or in combination: bioaugmentation with bacterial consortia, mycorrhizal fungi and a commercial mineral amendment. Microbial activity in soil, plant physiological parameters and heavy metal content in plants and in soil were monitored. Five months after the beginning, an early assessment of the toolbox under field conditions was carried out. Despite the cold season (October–March), results suggested the following: (1) the field setup as well as the experimental design proved to be effective; (2) plant survival was satisfactory; (3) soil quality was increased and bioaugmentation improved microbial activity, expanding the metabolic competences towards plant interaction (root exudates); and (4) multivariate analysis supported the data provided that the proposed toolbox can be established and the field trial can be carried forward.  相似文献   

11.
Today, urban runoff is considered as an important source of environmental pollution. Roofing materials, in particular, the metallic ones, are considered as a major source of urban runoff metal contaminations. In the context of the European Water Directive (2000/60 CE), an accurate evaluation of contaminant flows from roofs is thus required on the city scale, and therefore the development of assessment tools is needed. However, on this scale, there is an important diversity of roofing materials. In addition, given the size of a city, a complete census of the materials of the different roofing elements represents a difficult task. Information relating roofing materials and their surfaces on an urban district do not currently exist in urban databases. The objective of this paper is to develop a new method of evaluating annual contaminant flow emissions from the different roofing material elements (e.g., gutter, rooftop) on the city scale. This method is based on using and adapting existing urban databases combined with a statistical approach. Different rules for identifying the materials of the different roofing elements on the city scale have been defined. The methodology is explained through its application to the evaluation of zinc emissions on the scale of the city of Créteil.  相似文献   

12.
The understanding of the global environmental multiphase distribution of persistent organic pollutants (POPs) as a result of the physico-chemical properties of the respective compounds is well established. We have analysed the results of a vertical transport of POPs from surface water to deepwater in terms of the contamination of the biota living in the respective environmental compartments. Samples were taken from the North and the South Atlantic and from the uprising water region of the continental shelf of California (Marine Sanctuary Monterey Bay and its Canyon). The contents of persistent organochlorine pesticides (DDTs, chlordanes, toxaphenes, HCHs, and HCB) in surface-living fish are compared to those in deepwater fish of the same geographic area. The deepwater biota show significantly higher burdens as compared to surface-living species of the same region. There are also indications for recycling processes of POPs of the class of organochlorine pesticides in the biophase of the abyss as well. It can be concluded that the bio- and geophase of the deep-sea may act as an ultimate global sink for persistent semivolatile contaminants in the marine environment like the soil on the continents.  相似文献   

13.

In the present study, bio-apatite/nZVI composite was synthesized through Fe(III) reduction with sodium borohydride and was fully characterized by FTIR, XRD, SEM–EDX, TEM, BET, BJH, and pHPZC. Column experiments were carried out for the removal of phosphate as a function of four operational parameters including initial phosphate concentration (100–200 mg L?1), initial solution pH (2–9), bed height (2–6 cm), and influent flow rate (2.5–7.5 mL min?1) using a response surface methodology (RSM) coupled with Box-Behnken design (BBD). 2D contour and 3D surface plots were employed to analyze the interactive effects of the four operating parameters on the column performance (e.g., uptake capacity and saturation time). According to ANOVA analysis, the influent flow rate and bed height are the most important factor on phosphate uptake capacity and saturation time, respectively. A quadratic polynomial model was excellently fitted to experimental data with a high coefficient of determination (>?0.96). The RSM-BBD model predicted maximum phosphate adsorption capacity of 85.71 mg g?1 with the desirability of 0.995 under the optimal conditions of 135.35 mg L?1, 2, 2 cm, and 7.5 mL min?1 for initial phosphate concentration, initial solution pH, bed height, and influent flow rate, respectively. The XRD analysis demonstrated that the reaction product between bio-apatite/nZVI composite and phosphate anions was Fe3 (PO4)2. 8H2O (vivianite). The suggested adsorbent can be effectively employed up to five fixed-bed adsorption–desorption cycles and was also implemented to adsorb phosphate from real samples.

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14.
This paper explored biochar modification to enhance biochar’s ability to adsorb hexavalent chromium from aqueous solution. The ramie stem biomass was pyrolyzed and then treated by β-cyclodextrin/poly(L-glutamic acid) which contained plentiful functional groups. The pristine and modified biochar were characterized by FTIR, X-ray photoelectron spectroscopy, specific surface area, and zeta potential measurement. Results indicated that the β-cyclodextrin/poly(L-glutamic acid) was successfully bound to the biochar surface. Batch experiments were conducted to investigate the kinetics, isotherm, thermodynamics, and adsorption/desorption of Cr(VI). Adsorption capacities of CGA-biochar were significantly higher than that of the untreated biochar, and its maximum adsorption capacity could reach up to 197.21 mg/g at pH 2.0. Results also illustrated that sorption performance depended on initial solution pH; in addition, acidic condition was beneficial to the Cr(VI) uptake. Furthermore, the Cr(VI) uptake was significantly affected by the ion strength and cation species. This study demonstrated that CGA-biochar could be a potential adsorbent for Cr(VI) pollution control.  相似文献   

15.
16.
Levels of eight PCB congeners and thirteen organochlorine pesticides were measured in eggs sampled at four yellow-legged gull colonies from the Aegean Sea (NorthEastern Mediterranean) in 1997. There were no significant differences among colony areas in the median concentrations in any of the pollutants whereas cluster analyses did not generally reveal reasonable pollution patterns. The maximum concentrations of four congeners were found at Kinaros colony and of nine compounds were found at Lipsos colony. Fingerprints in both groups were similar in all areas. Of PCBs, congener 28, 118, 138, 180 and of pesticides beta-BHC and 2,4'-DDD were prominently dominant suggesting a particular pollution pattern in this region. Statistically significant correlations were found between most of the higher PCBs in all areas studied. The DDT metabolites correlated mostly with other OCs. We suggest that regional pollution by both groups is not adequately reflected in the eggs of this gull probably due to its extensive scavenging habits and, though information is needed from more colonies, it seems to be a poor biomonitor for organochlorines in this region.  相似文献   

17.
Two crops of Brassica juncea (L.) Czern. were grown in a field experiment, at the site affected by the toxic spillage of acidic, metal-rich waste in Aznalcóllar (Seville, Spain), to study its metal accumulation and the feasibility of its use for metal phytoextraction. The effects of organic soil amendments (cow manure and mature compost) and lime on biomass production and plant survival were also assessed; plots without organic amendment and without lime were used as controls. Plots, with or without organic amendment, having pH < 5 were limed for the second crop. Soil acidification conditioned plant growth and metal accumulation. The addition of lime and the organic amendments achieved higher plant biomass production, although effects concerning metal bioavailability and accumulation were masked somewhat by pH variability with time and between and within plots. Tissue metal concentrations of B. juncea were elevated for Zn, Cu and Pb, especially in leaves of plants from plots with low pH values (maxima of 2029, 71 and 55 microg g(-1), respectively). The total uptake of heavy metals in the plants was relatively low, emphasising the problems faced when attempting to employ phytoextraction for clean-up of pluri-contaminated sites.  相似文献   

18.
The bioaccumulation of six metals (Fe, Mn, Zn, Cd, Pb and Cu) was studied as part of the monitoring of the Aznalcóllar mining spill (April 1998) on the Guadalquivir estuary and in other estuaries located in the Gulf of Cádiz. Fish, clams and oysters were collected during different seasonal periods along the years 2000 and 2001 in the Guadalquivir estuary to determine the bioaccumulation of the metals originated by the mining spill. Results were compared to the bioaccumulation of the same metals in fish and clams exposed in the laboratory to sediments collected in the same areas during autumn 2001. The bioaccumulation of these metals was compared to the concentration of metals measured in tissues of same taxas collected in the areas of the ria of Huelva and the Bay of Cádiz. Results show that the bioaccumulation of Zn and Cd in the organisms sampled in the Guadalquivir estuary was associated with the enrichment of these metals in the estuary from the mining spill and decreased along the time reaching the lowest values in autumn 2001. The metal Cu show different trends that are associated with other sources of contamination than the spill and related to the transport of this metal from Huelva to Guadalquivir estuary and/or to the use of this metal as plaguicide in the rice fields located in the area. The comparison between bioaccumulation results under field and laboratory conditions obtained in the different areas of study shows that these data can be used to discriminate between acute and chronic impacts associated with mining activities.  相似文献   

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