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341.
Abstract

An extensive investigation was carried out for the characterisation of the air particulate composition in Florence. The aim was to determine the aerosol elemental concentrations, as well as to identify pollution sources. For our investigation, the external Particle-Induced X-Ray Emission–Particle-Induced γ-Ray Emission beam facility of the Istituto Nazionale di Fisica Nucleare, Van de Graaff accelerator at the Physics Department of the Florence University was used. We report the results of the analysis of a long temporal series (approximately 1 yr) of PM10 particulate samples, collected on Millipore filters on a daily basis in three different sites (characterised by different urban settings). Daily concentrations of more than 20 elements were detected. The long sampling period (approximately 1 yr) allowed a comparison with the air quality recommended values and the identification of seasonal variations. Four main sources (traffic, oil-combustion, soil-dust, and wind transported sea-salt) were extracted with the help of Principal Component Analysis (PCA). An absolute PCA showed traffic to be the major source both in the high traffic site and in the urban background site.  相似文献   
342.
In this paper new analytical inspection strategies, based on hyperspectral imaging (HSI) in the VIS–NIR and NIR wavelength ranges (400–1000 and 1000–1700 nm, respectively), have been investigated and set up in order to define quality control logics that could be applied at industrial plant level for polyolefins recycling. The research was developed inside the European FP7 Project W2Plastics “Magnetic Sorting and Ultrasound Sensor Technologies for Production of High Purity Secondary Polyolefins from Waste”. The main aim of the project is the separation of pure polyethylene and polypropylene adopting an innovative process, the magnetic density separation (MDS). Spectra of plastic particles and contaminants resulting from post-consumer complex wastes and of virgin polyolefins have been acquired by HSI and by Raman spectroscopy. The classification results obtained applying principal component analysis (PCA) on HSI data have been compared with those obtained by Raman spectroscopy, in order to validate the proposed innovative methodology. Results showed that HSI sensing techniques allow to identify both polyolefins and contaminants. Results also demonstrated that HSI has a great potentiality as a tool for quality control of feed (identification of contaminants in the plastic waste) and of the two different pure polypropylene and polyethylene flow streams resulting from the MDS-based recycling process.  相似文献   
343.
Ratola N  Alves A  Santos L  Lacorte S 《Chemosphere》2011,85(2):247-252
Eight polybrominated diphenyl ethers (PBDEs) were determined in pine needles of three species (Pinus halepensis, Pinus pinea and Pinus nigra) collected in the NE Spain in an attempt to use this matrix for the biomonitoring of airborne PBDEs. The method used was based in ultrasonic extraction followed by alumina and Florisil clean-up and determination by gas chromatography coupled to mass spectrometry in negative chemical ionization. Recoveries were between 99% and 138%, limits of detection between 0.011 and 0.070 ng g−1-dw (0.232 ng g−1-dw for BDE 209) and repeatability lower than 13%. PBDE levels ranged between 0.027 ng g−1-dw and 13.04 ng g−1-dw, with predominance of BDE 209, followed by BDEs 47. P. halepensis was the species with the highest PBDE levels and P. nigra, the least, according to their widespread and remote distribution, respectively. The presence of PBDEs in pine needles was attributed to the release of in-use PBDEs, transport through atmosphere and adsorption upon lipid rich pine needles. Given the easy collection of pine needles, its ample distribution and its potential to accumulate airborne contaminants, this matrix is proposed as passive bio-sampler to be used in PBDE monitoring programs.

Capsule

Pine needles can be used to biomonitor airborne PBDEs.  相似文献   
344.

Purpose  

Metal bioavailability-based sediment quality analysis, inferred from geochemical partitioning data, may contribute to improve sediment management policies. This is important because decision-making processes should not give similar priorities to sediments offering contrasting environmental risks associated to metal bioavailability. However, current uses of Sediment Quality Guidelines (SQGs) as interpretive tools to support decisions about dredging-related activities have not considered the changes in metal bioavailability upon sediment resuspension.  相似文献   
345.
Chitosan films (CF) [1 and 2% w/v] alone and with cinnamaldehyde (CNE) [0.25, 0.5 and 1% v/v] were prepared using an emulsion method, and the obtained films were characterized in terms of water vapor permeability (WVP), water solubility and optical, mechanical and antioxidant properties. The incorporation of CNE at 1% (v/v) significantly decreased the water solubility of the film by approximately 4% for the 1 and 2% CF films, whereas the WVP increased (2.5–3.5 times). The incorporation of CNE (0.25 and 0.5%) into 2% CF significantly increased the tensile strength (TS) (62 and 34%, respectively) and the percent elongation (%E) values, 26, 30 and 52% for CF that contained 0.25, 0.5 and 1% CNE, respectively. The largest value of the elasticity modulus (EM) was observed for 2% CF with 0.25% CNE. All films exhibited a yellow appearance (b*), but the CNE content had a marked impact on the coloration of the films. The CNE recoveries of the CF films (1 and 2%) with 1% of CNE were high (43 and 67%). The antioxidant activities indicated that the incorporation of 1% CNE into CF films (1 and 2%) increased the antioxidant activity. The protective effects of the films with and without CNE on erythrocytes were very strong (36–72% hemolysis inhibition). These results suggest there are potential applications for CF-CNE films as active packaging for the preservation of food products.  相似文献   
346.
Upper limb work-related musculoskeletal disorders have a 12-month prevalence ranging from 12 to 41% worldwide and can be partly caused by handling low loads at high frequency. The association between the myoelectric manifestation of elbow flexor muscle fatigue and occupational physical demand has never been investigated. It was hypothesized that an elbow flexor muscle fatigue index could be a valid risk indicator in handling low loads at high frequency. This study aims to measure the myoelectric manifestation of muscle fatigue of the three elbow flexor muscles during the execution of the work tasks in different risk conditions. Fifteen right-handed healthy adults were screened using a movement analysis laboratory consisting of optoelectronic, dynamometer and surface electromyographic systems. The main result indicates that the fatigue index calculated from the brachioradialis is sensitive to the interaction among risk classes, session and gender, and above all it is sensitive to the risk classes.  相似文献   
347.
At Seveso plants, duty holders must have a complex system for assessing and managing risks. The pillars of this system are the safety report and the safety management system, with a number of underlying documents. The strength of the system is the high standardization of these documents. Regulations, standard codes and guidelines define content, structure and formats. The weakness is the high complexity. Managers and workers perceive documents as difficult to understand and far from actual operations. Major threats for the credibility of documents (and therefore for the safety systems) come from the continuous organizational and technical changes, which in a short time can make most documents obsolete; as well as by near misses, which continuously show the holes in safety systems. A big effort is required to follow up the plant changes and the near misses. In order to help safety managers, a new software has been developed. At Seveso plants, it has been possible build an integrated digital representation, because all documents are perfectly structured. This representation may be used both for updating the relevant documents after a change and to improve documents after a near miss or an accident. In this way, safety documents are always up to date and trustworthy and the huge knowledge, which is usually hidden inside safety documents, is clearly revealed and revived. The approach is basically “knowledge based” and the intention is to provide safety managers with an easy and simple tool. IRISonLine is a software that has been developed by ISPESL to provide safety managers of “Seveso” establishments with a tool for improving the management of change and of near misses.  相似文献   
348.
The ecological risks of polynuclear aromatic hydrocarbons (PAH) in aquatic sediments will vary with both toxicity and bioavailability to aquatic biota. While there are standardized protocols to test the acute toxicity of sediment-borne compounds to aquatic invertebrates, there are none for assessing bioavailability to fish. We found that sediment-borne PAH caused an exposure-dependent induction of cytochrome P450 (CYP1A) enzymes in rainbow trout (Oncorhynchus mykiss) fingerlings exposed in semi-static 96 h bioassays, as shown by increased activity of ethoxyresorufin-o-deethylase (EROD). Assuming that PAH are taken up by trout due to partitioning from organic and inorganic constituents of sediments, we tested the effect of different test variables on bioaccumulation using induction as an index of exposure. EROD activity increased with exposure of fish to increasing volumes of sediments containing PAH, i.e., with increasing ratios of sediment to water. Uptake of single compounds from sandy sediments did not differ from uptake from clay or low organic (7% LOI — loss on ignition) sediments, but decreased when organic content was very high (58% LOI). Maximum induction was observed within 24~h of exposure and at 7.5^C relative to 15, 22, or 28^C. Storage and handling techniques had minor effects on sediment EROD induction potency. Absolute EROD activity was greater in white sucker (Catostomus commersoni) a benthic species, than in trout, a pelagic species. However, when basal (negative control) activity was accounted for, there was no difference in response between the species. Together, these experiments provide a basis for developing a standard protocol to test the bioavailability to fish of sediment-borne PAH.  相似文献   
349.
Five priority areas of potential impact by contaminants (API) were investigated at the Presidente Bernardes Refinery in Cubatão, São Paulo, Brazil with the following aims: (i) to identify both organic and inorganic contaminants present in soil and groundwater; (ii) to define the environmental conditions relevant for microbial activity at the site and (iii) to evaluate the feasibility of employing natural attenuation for treatment of the hydrocarbon contamination. One area (API 1) was an uncontrolled landfill, where waste materials from the refinery were deposited between 1954 and 1986, and four areas (API 4, 5, 7 and 11) were located in the operational section of the refinery. Soil contamination by regulated BTEX compounds (benzene, toluene, total xylenes) was restricted to two samples from API 1. Nonregulated ethylbenzene was detected in one soil sample from API 4, one from API 5 and two from API 1. No soil contained regulated PAH above threshold levels. Several nonregulated PAHs were found in 6 soil samples from API 1, 3 soil samples from API 4 and 1 soil sample from API 5. Site soils contained very high aluminium concentrations, but metal contamination was restricted to one soil sample from API 1, which contained nickel above threshold limits. BTEX contamination of groundwater was due mostly to benzene. Of the 17 PAH molecules tested, only naphthalene and 2-methylnaphthalene occurred in groundwater. The sum of total BTEX and total PAH exceeded 200 μg/L in only a few monitoring wells in API 4, 5 and 11 and was always below 2.640 μg/L. Be, Cd, Cr, Cu, Hg, Ni, Se, Ag, Tl and Zn were not detected in groundwater, which was contaminated in a few locations by aluminium (mostly below 1 mg/L), lead (<0.066 mg/L) and arsenic (<0.056 mg/L). S, K, Ca, Mg and Fe were present in groundwater in excess of physiological requirements for microbial growth, but low concentrations of N and P could become growth limiting. However, BTEX were efficiently degraded in saturated and unsaturated zone microcosms and nutrient amendments did not stimulate biodegradation rates measurably. The inorganic carbon pool in groundwater was up to one order of magnitude larger than the organic carbon pool. Total inorganic carbon (TIC) in API groundwater exceeded TIC of clean groundwater by factors of 2 (API 4), 6 (API 5, 7 and 11) or 10 (API 1). Most of the inorganic carbon incorporated into groundwater beneath the refinery originated from biodegradation in the unsaturated soil, which contained a microbiota (106 cells/g on average) capable of growth with most of the pure (benzene, toluene, ethylbenzene and xylene) and mixed hydrocarbons tested (diesel oil, gasoline, naphtha, condensate, aromatic residue and fuel oil). A viscous hydrocarbon paste uncovered in API 1 was insoluble in water but dissolved in dichloromethane. Many organic components of this paste were biodegradable as evidenced by weight reduction of the hydrocarbon paste and by the growth of suspended and attached biomass in saturated zone microcosms, where the paste was the only carbon source. This study indicates that monitored natural attenuation may be a technically feasible and efficient means for plume control in API 1, 4 and 5, provided the plumes in API 4 and 5 are not expanding. This technique is not suitable for contaminant reduction in API 11.  相似文献   
350.
The aim of this work is the analysis of the dynamics in cultural landscapes, focused on the spatial distribution of changes in land cover and landscape patterns, and their possible linkages. These dynamics have been analyzed for the years 1957 and 2000 in a sector of the north of Galicia (NW Spain) characterized with diverse landscapes. Afforestation processes linked to agriculture abandonment and forestry specialization were the main processes observed in the study area, with the exception of the southern mountainous sector that was dominated by ploughing of scrubland for conversion into grassland, reflecting a specialization in livestock production. The structural changes that have taken place in most of the study area were related to the heterogeneity aspects, although the mountainous sectors were characterized by changes in heterogeneity and fragmentation. According to the tests performed, the comparison of the spatial distribution of both dynamics showed a certain statistical significance, reflecting the interrelationship between patterns and processes. This approach could be useful for the identification of areas with similar characteristics in terms of spatial dynamics so as to define more effective and targeted landscape planning and management strategies.  相似文献   
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