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111.
The paper presents the results of studies on selecting a solid sorption material for absorbing liquid crop protection agents which permeate samples of protective clothing fabrics. The sorption materials were investigated and selected with an assumption that they should have a high recovery coefficient for biologically active substances, used as active ingredients in crop protection agents, at a presumed, acceptably high level. The selected substances were determined with a gas chromatograph equipped with an electron capture detector (dichlorvos, cypermethrin and 2,4-D) and a nitrogen-phosphorus detector (carbofuran). The tests demonstrated that polypropylene melt-blown type unwoven cloth had high recovery coefficients for all 4 active ingredients proposed for the study. The highest recovery coefficient, -.97, was obtained for carbofuran. The recovery coefficients obtained for the 3 remaining substances were lower: .89 for cypermethrin and 2,4-D, and .84 for dichlorvos.  相似文献   
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Toxicity of some organic and inorganic chemicals to microorganisms is an important consideration in assessingtheir environmental impact against their economic benefits.Microorganisms play an important role in several environmentalprocesses, both natural and engineered. Some organic and inorganics at toxic levels have been detected in industrial discharges resulting in plant upsets and discharge permit violations. In addition to this, even though in some cases the effluent wastewater does not exceed the discharge limits,the results of toxicity tests show potential toxicity. Toxicityknowledge of effluents can benefit treatment plant operators inoptimising plant operation, setting pre-treatment standards, and protecting receiving water quality and in establishing sewer discharge permits to safeguard the plant. In the Turkish regulations only toxicity dilution factor (TDF) with fish is part of the toxicity monitoring program of permissible wastewater discharge. In various countries, laboratory studiesinvolving the use of different organisms and protocol for toxicity assessment was conducted involving a number of discharges.In this study, it was aimed to investigate the acute toxicity of textile and metal industry wastewaters by traditional and enrichment toxicity tests and emphasize the importance of toxicity tests in wastewater discharge regulations. The enrichment toxicity tests are novel applications and give anidea whether there is potential toxicity or growth limiting and stimulation conditions. Different organisms were used suchas bacteria (Floc and Coliform bacteria) algae (Chlorella sp.), fish (Lepistes sp.) and protozoan (Vorticella sp.) to represent four tropic levels. The textile industry results showed acute toxicity for at least one organism in 8 out of 23 effluent samples. Acute toxicity for at least two organisms in 7 out of 23 effluent sampling was observed for the metal industry. The toxicity test results were assessed with chemical analyses such as COD, BOD, color and heavy metals. It was observed that the toxicity of the effluents could not be explained by using physicochemical analyses in 5 cases for metal and 4 cases for the textile industries. The results clearly showed that the useof bioassay tests produce additional information about the toxicity potential of industrial discharges and effluents.  相似文献   
114.
This work was aimed at finding materials that could be used as alternatives to lichens as air quality monitors since the high natural variability and the large amount of lichen collected are two drawbacks of the use of these organisms. Lichen Flavoparmelia caperata(L.) Hale was exposed in three different forms (transplant, detached from the substratum and as a biomass-ground and homogeneized) and compared to the planetree bark (Platanus hybrida Brot.), exposed as a biomass, and two organic synthetic materials (Chelex(R) 100 resin and cellulose acetate). Materials were exposed for two months in the winter, spring and summer, at three Portuguese coastal cities. The results showed that the airborne accumulations of Cu, Ni, Pb and Sr were partially dependent on the meteorological conditions but mainly dependent on the nature of the exposed material. The standard deviations of the synthetic materials or homogenized biomass were the same or greater than lichen transplants or detached. The accumulation by biological materials, of the four studied elements, was comparable to the lichen transplant accumulation. The replacement of the traditional transplants by the biomass was not considered advantageous, since their preparation is time-consuming. Therefore lichens remain the most suitable in biomonitoring studies. The exposure of detached lichen allows the accurate measurement of the exposed area/volume so it can be useful to relate atmospheric deposition rates with the lichen metal content. The synthetic materials accumulated Cu and Ni and should only be used as an alternative to traditional transplants when these are the elements of interest.  相似文献   
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Environmental Science and Pollution Research - The use of composts and vermicomposts as adsorbents is an important topic of study in the field of environmental remediation. These materials are rich...  相似文献   
116.
The amount of extruded polystyrene (XPS) waste has increased in recent years due to the increase of its use in the thermal insulation of buildings, transport vehicles, and refrigerators, among others. Dissolution with suitable solvents to achieve a volume reduction of more than 100 times without degradation of polymer chains is one of the cheapest and most efficient methods of recycling XPS. Several environmentally friendly solvents have been tested as dissolution agents for XPS volume reduction; the action of these solvents does not produce any degradation of polymer chains. The solubility of the polymer in such solvents at different temperatures was investigated. The solvent can be easily recycled by distillation, obtaining a high-quality recycled polymer. Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6  相似文献   
117.
The Sarno River is nicknamed “the most polluted river in Europe”. The main goal of this study is to enhance our knowledge on the Sarno River water and sediment quality and on its environmental impact on the gulf of Naples (Tyrrhenian Sea, Central Mediterranean Sea) in order to become a useful assessment tool for the regional administrations. For these reasons, 32 selected polychlorinated biphenyls (PCBs) and aldrin, α-BHC, β-BHC, δ-BHC, γ-BHC (lindane), 4,4′-DDD, 4,4′-DDE, 4,4′-DDT, dieldrin, endosulfan I, endosulfan II, endosulfan sulphate, endrin, endrin aldehyde, heptachlor, heptachlor epoxide (isomer B) and methoxychlor were determined in the water dissolved phase (DP), suspended particulate matter (SPM) and sediments. Total concentrations of PCBs ranged from 1.4 to 24.9 ng L?1 in water (sum of DP and SPM) and from 1.01 to 42.54 ng g?1 in sediment samples. The concentrations of total organochlorine pesticides (OCPs) obtained in water (sum of DP and SPM) ranged from 0.54 to 7.32 ng L?1 and from 0.08 to 5.99 ng g?1 in sediment samples. Contaminant discharges of PCBs and OCPs into the sea were calculated in about 1,247 g day?1 (948 g day?1 of PCBs and 326 g day?1 of OCPs), showing that this river should account as one of the main contribution sources of PCBs and OCPs to the Tyrrhenian Sea.  相似文献   
118.
Fifty samples of finished drinking waters (FDWs) from Spain covering 12 million inhabitants were tested for 53 pharmaceuticals pertaining to 12 different Anatomical Therapeutic Chemical (ATC) classification system codes. The studied compounds are a combination of most commonly consumed pharmaceuticals with other barely reported in the literature. Five compounds, azithromycin, clarithromycin, erythromycin, sulfamethoxazole, and ibuprofen were tentatively identified by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) in some samples (2 to 15 %), but only ibuprofen and azithromycin could be confirmed when analyzed by liquid chromatography–high-resolution mass spectrometry (LC-HRMS) with a quadrupole-Orbitrap instrument. Concentration levels of ibuprofen in the positive samples ranged from 12 to 17 ng/L (n?=?6) while for azithromycin values from 5 to 9.5 ng/L (n?=?3) were found. Ibuprofen fragmentation behaviour in different mass spectrometry instrument configurations (triple quadrupole, quadrupole-ion trap, and quadrupole-Orbitrap) was evaluated.  相似文献   
119.
The recent increase in European temperatures led to a strong enhancement in the occurrence of extremely warm events, with relevant consequences for environment and everyday life. Here, we investigate the evolution of very intense warm and cold events in a south-western European zone during 1961–2007 at a seasonal level. Special attention is given to summertime when warming is the most pronounced. Using a previously developed theoretical model, we discuss how the average properties and long-term trends observed in probability density functions of daily temperatures can explain changes in the frequency of severe, isolated events. In this perspective, the recent intensification of extremely warm events, especially experienced by the Mediterranean zone, is proved to be well consistent with a pure shift of seasonal mean temperatures. On the other hand, any change in the second and higher distributional moments of daily temperatures is ruled out by the data, whereas the average values of these properties, that is, variability and asymmetry, do play a role by shaping the temporal behavior of very intense events.  相似文献   
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