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81.
/ In modern intensive animal farming the disposal of a large amount of waste is of great concern, as, if not properly performed, it can cause the pollution of water, mainly because of the high content of nitrate and phosphate. This paper presents the results of a study intended to assess the environmental sustainability of animal waste disposal on agricultural soils in the alluvial plain of the River Chiana (Tuscany, Italy), a particularly sensitive area because of the high vulnerability of the shallow aquifer and of the intensive agricultural and breeding activities. With this aim, a strategy has been employed, that consists of the integrated use of a management model and GISs. The consequences on groundwater of applying animal waste to different kind of soils and crop arrangements have been simulated by means of the management model GLEAMS (Groundwater Loading Effects of Agricultural Management Systems, ver 2.01). As the huge amount of data required by such a sophisticated model does not allow applications at a scale larger than the field size, IDRISI and GRASS GIS packages have been used to divide the study area into land units, with homogeneous environmental characteristics, and then to generalize on these units the outputs of the model. The main conclusions can be synthesized as follows: The amount of animal waste produced in some of the investigated areas (i.e., municipal territory) is greater than that disposable on their own agricultural soil with no risks to the groundwater; consequently a cooperative approach among municipalities is necessary in order to plan waste disposal in a comprehensive and centralized way.KEY WORDS: Land use; Animal waste disposal; Groundwater protection; GIS, Management models  相似文献   
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The composition of airborne particulate matter sampled by a conventional TEOM®, an experimental modified TEOM, operated at a lower temperature but fitted with a drier to remove moisture and a Partisol®, installed at a kerbside site in the North East of England, has been investigated. The results indicate that there is a seasonal variation in the composition of PM10 as sampled by the three monitors, with chloride concentration being significantly higher in the winter. The Partisol was found to sample a higher mass of chloride and nitrate, however the differences between the monitors was only significant for chloride. Both TEOM's were found to sample a greater mass of sulphate, although the variability in the data collected meant that significance of the results was not proven statistically. The range of artifacts associated with PM10 monitors is reviewed. Difficulties in the interpretation of results due to the variable nature of airborne particulate matter and the ability of filter based systems to accurately represent the composition of atmospheric particles are considered.  相似文献   
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A method for determination of the climate gases CH4, CO2 and N2O in air samples and soil atmosphere was developed using GC-MS. The method uses straightforward gas chromatography (separation of the gases) with a mass spectrometric detector in single ion mode (specific determination). The gases were determined with high sensitivity and high sample throughput (18 samples h(-1)). The LOD (3sigma) for the gases were 0.10 micro L L(-1) for CH4, 20 microL L(-1) for CO2 and 0.02 microL L(-1) for N2O. The linear range (R2 = 0.999) was up to 500 microL L(-1) for CH4, 4000 microL L(-1) for CO2 and 80 microL L(-1) for N2O. The samples were collected in 10 mL vials and a 5 microL aliquot was injected on column. The method was tested against certified gas references, the analytical data gave an accuracy within +/-5% and a precision of +/-3%. The presence of < or = 10% by volume of C2H2 (often used experimentally to prevent N2 formation from N2O) did not interfere with detection for the targeted trace gases.  相似文献   
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The study focuses on analysing the evolution of environmental impacts caused by a medium–large Italian WtE plant before and after revamping and maintenance operations, with the aim of providing an evaluation of how much these structural upgrade measures may affect the total environmental performance.LCA methodology was applied for the modelling and comparison of six WtE scenarios, each describing the main structural upgrades carried out in the plant over the years 1996–2011. The comparison was conducted by adopting 1 ton of MSW as the functional unit, and the net contribution from energy recovery to power generation was distinguished by defining consistent national grid electricity mixes for every year considered. The Ecoindicator99 2.09 impact assessment method was used to evaluate the contribution to midpoint and endpoint categories (e.g. carcinogens, respiratory inorganics and organics, climate change, damage to human health). Lastly, the “Pedigree quality matrix” was applied to verify the reliability and robustness of the model created.As expected, the results showed better environmental scores after both the implementation of new procedures and the integration of operations. However, while a net reduction of air emissions seems to be achievable through dedicated flue gas treatment technologies, outcomes underscored potentials for improving the management of bottom ash through the adoption of alternative options aimed to use that solid residue mainly as filler, and to decrease risks from its current disposal in landfill. If the same effort that is put into flue gas treatment were devoted to energy recovery, the targets for the WtE plant could be easily met, achieving a higher sustainability. This aspect is even more complex: national policies for implementing greener and renewable energy sources would result in a lower impact of the national energy mix and, hence, in a lower net avoided burden from energy recovery.The study confirmed the expected improvements, indicating quantitatively the lower environmental impact resulting from structural upgrade operations in a WtE plant. Furthermore, the work highlights the importance of considering the evolution of the national energy mix in LCA studies, especially during the present years of transition from fossil fuels to renewable sources.  相似文献   
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This paper examines the effects of individuals' primary and multiple developmental relationships in a longitudinal study of the careers of lawyers. By juxtaposing the effects of the primary developmental relationship with those of individuals' sets or ‘constellations’ of developmental relationships, the present study lends insight into if and when these two perspectives on mentoring yield different results regarding the effects of mentoring on protégé career outcomes. The findings from the present study show that while the quality of one's primary developer affects short‐term career outcomes such as work satisfaction and intentions to remain with one's firm, it is the composition and quality of an individual's entire constellation of developmental relationships that account for long‐run protégé career outcomes such as organizational retention and promotion. Further, results from the present study provide evidence that the constellation perspective explains greater variance with respect to protégé career outcomes than does the primary or more traditional perspective on mentoring. Implications for research on mentoring, developmental relationships, and careers are discussed. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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The aim of this paper is to assess, through an empirical investigation, whether the performance of safety management systems (SMSs) adopting and non-adopting companies statistically differ. To achieve such aim, empirical data were collected on a sample of 116 companies, encompassing both SMSs adopters and non-adopters. Hypotheses testing was performed to assess whether SMSs adopters experience significantly higher performance against (i) definition of safety and security goals and their communication to employees; (ii) risk data updating and risk analysis; (iii) identification of risks and definition of corrective actions; (iv) employees training. Results show that companies adopting SMSs exhibit higher performance against all the topics identified. These outcomes could be the starting point for providing empirical evidence of benefits achievable thanks to SMSs implementation.  相似文献   
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