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Adsorption of Fluoroquinolone Antibiotics by Wastewater Sludge Biochar: Role of the Sludge Source
2013
Yao, Hong | Lu, Jian | Wu, Jun | Lu, Zeyu | Wilson, P Chris | Shen, Yan
Adsorption of fluoroquinolone antibiotics using sludge-derived biochar made of various wastewater sludges was investigated. The sludge-derived biochar had relatively large Brunauer–Emmet–Teller specific surface areas that were beyond 110.0 m² g⁻¹ except the biochar made from the sludge collected from traditional sludge drying bed. The mesopore capacity was more than 57 % of the total pore capacity of all sludge-derived biochar except that made from the sludge dried through traditional sludge drying bed technique. High adsorption capacity of sludge-derived biochar was observed with a highest adsorption capacity of 19.80 ± 0.40 mg g⁻¹. High correlation between the adsorption capacity of sludge-derived biochar and the volatile content in the sludge source was observed. The Freundlich model (r ² values were in the range of 0.961–0.998) yielded the best fit with the experimental data of all the produced biochar. Fluoroquinolone antibiotics were readily adsorbed onto sludge-derived biochar. These findings suggest a new approach for the pollution control of fluoroquinolone antibiotics using low-cost sludge-derived biochar.
显示更多 [+] 显示较少 [-]Pesticide risk assessment and management in a globally chgangin world - report from a european interdisciplinary workshop
2013
Babut, M. | Arts, G.H.P. | Barra Caracciolo, A. | Carluer, N. | Domage, N.
Radiocesium Fallout in Surface Soil of Tomakomai Experimental Forest in Hokkaido due to the Fukushima Nuclear Accident
2013
Hao, Le Cong | Nitta, Miyako | Fujiyoshi, Ryoko | Sumiyoshi, Takashi | Van Tao, Chau
Traces of short- and long-lived fallout ¹³⁴Cs and ¹³⁷Cs were found in surface soil (volcanic ash soil) under a cool-temperate deciduous stand at Tomakomai Experimental Forest in Hokkaido, Japan after the Fukushima nuclear accident in March 2011. Most of them were present in the uppermost 5–6 cm of the soil. Mean concentrations of ¹³⁴Cs and ¹³⁷Cs were found to be 2.4 (±0.3) and 89 (±2) Bq Kg⁻¹ in May, and 6.9 (±0.4) and 94 (±2) Bq Kg⁻¹ in November 2011, respectively. A small increase in radiocesium concentration may result from biological activity in the uppermost portion of the soil in which fallout nuclides derived from the Fukushima NPP would not have existed in May. They were supposed to be fallen down on the fresh litter layer in the previous year. The results of a sequential extraction experiment with 1 M CH₃COONH₄ solution showed that desorption of radiocesium from the soil was difficult and not simple ion exchange processes.
显示更多 [+] 显示较少 [-]A Pretreatment Method for Analysing Albendazole by HPLC in Plant Material
2013
Marciocha, D. | Kalka, J. | Turek-Szytow, J. | Surmacz-Górska, J.
Albendazole (ALB) belongs to a group of benzimidazoles - classified as antiparasitic pharmaceuticals. Its widespread application results in the presence of this pharmaceutical in natural environment (water and soil). In this paper a suitable pretreatment method was established including sampling, freeze-drying and extraction. Vicia faba was used as model organism. ALB accumulation by plant tissues was observed in hydroponic culture as well as in soil. The range of pharmaceutical concentrations was 1.7 × 10-5 mol/L (in hydroponic culture) and 1.7 × 10-5 to 1.7 × 10-4 mol/kg air dry soil (in soil). Observations were conducted for 14 days. After this time biological material was freeze-dried and after homogenization, dimethyl sulfoxide (DMSO) extraction was performed. The recovery of ALB for the roots was 93 % while for the shoots 86 %. After cleaning, the samples were subjected to further analysis by HPLC system. Phosphate buffer and acetonitrile (50:50) were used as a mobile phase. Drug retention time was 6.3 min. Results obtained in this experiment indicate higher drug accumulation in roots rather than in the hypocotyl part of the plant, cultivated both in soil and in hydroponic culture. © 2013 The Author(s).
显示更多 [+] 显示较少 [-]Acute Copper Toxicity and Acclimation to Copper Using the Behavioral Endpoint of Shoaling, in the Least Killifish (Heterandria formosa)
2013
Vogt, Sarah K. | Billock, Arlene G. | Klerks, Paul L.
While copper is known to be neurotoxic, effects on behavior and especially on group behavior have received much less attention. Yet such behavioral effects can have important ecological consequences. This study determined whether shoaling behavior could be used as an indicator of acute copper toxicity and as an endpoint in studying acclimation in the least killifish (Heterandria formosa). For acute toxicity, least killifish were exposed to 0, 25, 50, or 100 μg/L of Cu for a 2-h duration and then tested for changes in shoaling behavior. The occurrence of copper acclimation was tested by pre-exposing fish to either 0 or 15 μg/L of Cu for a 7-day duration, then exposing them to 25, 50, or 100 μg/L of Cu to assess whether the two pre-exposure groups differed in their behavioral responses to high Cu levels. Behavioral responses were tested in a subdivided aquarium, with one side containing a group of conspecific fish and the other side the focal fish whose behavior was recorded for 3 min. Shoaling was based on the proximity of the focal fish to the divider separating it from the group of conspecific fish. Acute copper exposure resulted in significant decreases in both the time to first shoaling and in the total amount of time spent shoaling. Experiments assessing the occurrence of copper acclimation using shoaling as the toxicity endpoint did not detect a difference between the pre-exposure groups. Overall, this study demonstrated that acute copper exposure can alter shoaling behavior. However, least killifish shoaling behavior appears to be relatively insensitive as an endpoint to assess copper acclimation. © 2013 Springer Science+Business Media Dordrecht.
显示更多 [+] 显示较少 [-]Quantifying source and dynamics of acidic pollution in a coastal acid sulphate soil area
2013
Phong, N. D. | Tuong, T. P. | Phu, N. D. | Nang, N. D. | Hoanh, Chu Thai
The in-depth knowledge on management and reducing annual acidic pollution is important for improving the sustainable livelihood of people living in areas with acid sulphate soils (ASS). This study involved a long-term (2001–2006), large-scale canal water quality monitoring network (87 locations) and a field experiment at nine sites to quantify the dynamic variability of acidic pollution and its source in a coastal area with ASS in the Mekong River Delta of Vietnam. Widespread acidic pollution (pH <5) of surface water occurred at the beginning of the rainy season, while pH of the canal water remained high (7–8) at the end of the rainy season and during the dry season. The study identified canal embankment deposits, made of ASS spoils from canal dredging/excavation, as the main source of acidic pollution in the surrounding canal network. The findings suggested that there was a linkage between the amount of acidic loads into canal networks and the age of the embankment deposits. The most acute pollution (pH ~ 3) occurred in canals with sluggish tidal water flow, at 1–2 years after the deposition of excavated spoils onto the embankments in ASS. The amount of acidic loads transferred to the canal networks could be quantified from environmental parameters, including cumulative rainfall, soil type and age of embankment deposits. The study implied that dredging/excavation of canals in ASS areas must be carried out judiciously as these activities may increase the source of acidic pollution to the surrounding water bodies.
显示更多 [+] 显示较少 [-]Carbon Activation for Hampering Oligomerization of Phenolics in Multicomponent Systems
2013
Yan, Liang | Sorial, George A.
The effectiveness of activated carbon sample (Carbonₑₓₚ) prepared by KOH chemical activation in hampering oligomerization of multicomponent adsorption was systematically examined. Anoxic (absence of molecular oxygen) and oxic (presence of molecular oxygen) adsorption isotherms of single-solute (2,4-dimethylphenol), binary solute (2-methylphenol/2,4-dimethylphenol), and ternary solute (phenol/2-methylphenol/2,4-dimethylphenol) were studied, using Carbonₑₓₚ and commercial granular activated carbon F400. Both binary solute adsorption and ternary solute adsorption on Carbonₑₓₚ indicated no impact of the presence of molecular oxygen on the adsorptive capacity. No significant differences between oxic and anoxic environment were noticed for any multicomponent adsorption systems, which indicated the effectiveness of Carbonₑₓₚ in hampering the oligomerization of phenolic compounds. On the other hand, in F400, which has lower microporosity and acidic functional groups, significant increases in the adsorptive capacity had been observed when molecular oxygen was present.
显示更多 [+] 显示较少 [-]Interaction of Novel Ionic Liquids with Soils
2013
Mrozik, Wojciech | Jungnickel, Christian | Paszkiewicz, Monika | Stepnowski, Piotr
With the constant development of new ionic liquids, the understanding of the chemical fate of these compounds also needs to be updated. To this effect, the interaction of a number of novel ionic liquids with soils was determined. Therefore, three novel headgroups (ammonium, phosphonium, or pyrrolidinium) with single or quaternary substitution were tested on a variety of soils with high-to-low organic matter content and high-to-low cation exchange capacity, thereby trying to capture the full range of possible soil interactions. It was found that the ionic liquids with single butyl alkyl chain interacted more strongly with the soils (especially with a higher cation exchange capacity), at lower concentrations, than the quad-substituted ionic liquids. However, the quad-substituted ionic liquids interacted more strongly at higher concentrations, due to the double-layer formation, and induced stronger dipole interaction with previously sorbed molecules.
显示更多 [+] 显示较少 [-]Antioxidant Defenses and Trace Metal Bioaccumulation Capacity of Cymbula nigra (Gastropoda: Patellidae)
2013
Rivera-Ingraham, G. A. | Malanga, G. | Puntarulo, S. | Pérez, A. F. | Ruiz-Tabares, A. | Maestre, M. | González-Aranda, R. | Espinosa, F. | García-Gómez, J. C.
The present study deals with the effect of trace metals on the endangered limpet Cymbula nigra. The Bay of Algeciras (Strait of Gibraltar) was used as the study site. Important industrial activity takes place in the area, including frequent oil spills. However, it is home to important populations of C. nigra. The objective of this work was to determine if these animals were being affected at a subcellular level by the pollutants present in their environment and to analyze the trace metal concentrations in the animal’s soft tissues. To determine the effects of water quality on the antioxidant activity and concentrations through field experimentation, a total of six sites were selected in Algeciras Bay, three located in the inner areas (environmentally degraded sites with higher levels of pollutants) and three in the outermost areas of the Bay. Stress associated to reactive oxygen species formation was assessed on digestive glands and gills as the enzymatic antioxidant activity of catalase (CAT), superoxide dismutase (SOD), and glutathione S-transferase (GST) and as the concentrations of lipid-soluble (α-tocopherol and β-carotene) and the water-soluble antioxidants (reduced and oxidized glutathione (GSH and GSSG)). Gills and digestive glands of those animals located in the inner areas of Algeciras Bay showed higher CAT activity values than those located in the outer areas. As a general pattern, we observed higher antioxidant activities and concentrations in digestive glands that in gills, suggesting the possibility that pollutants are mainly being incorporated by limpets through the food. As a general rule, larger animals showed greater concentrations of these compounds. Iron, zinc, and manganese, in this order, were present in the tissues at the highest concentrations. Chromium and manganese were found in significantly higher concentrations in those animals collected from the inner areas of the Bay. Through the present study, we provide the first data regarding the antioxidant defense levels and metal accumulation capacity of this species, and we reinforce the idea that this endangered species may be, in fact, relatively tolerant to degraded environments.
显示更多 [+] 显示较少 [-]Proposed Soil Indicators for Olive Mill Waste (OMW) Disposal Areas
2013
Doula, Maria K. | Kavvadias, Victor | Elaiopoulos, Kyriakos
The disposal of olive mill wastes (OMW) is considered as a major environmental problem worldwide, but especially for Mediterranean countries. Disposal in evaporation ponds or directly on soil is a common practice, which causes serious damages to soil and to the environment. The present study was performed in the framework of the LIFE project “Strategies to improve and protect soil quality from the disposal of Olive Mill Wastes in the Mediterranean region-PROSODOL” and one of its main objectives was the identification of appropriate soil parameters that could be used as soil indicators to assess soil quality at OMW disposal areas. For this, a well-designed soil sampling strategy was developed and implemented in Crete, South Greece at five OMW disposal areas. Many soil parameters were monitored bimonthly for a year. After statistical evaluation, eight soil parameters were selected as being appropriate soil indicators for OMW disposal areas, i.e., electrical conductivity, pH, organic matter, polyphenols, total N, exchangeable K, available P, and available Fe. Although many researchers have extensively studied the effect of OMW on soil quality, yet the identification of soil indicators to assess and monitor soil quality is an innovative issue and has never been studied before.
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