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81.
The Dutch Ministry of Social Affairs and Employment provided subsidy over the period 2004–2008 to a number of companies to introduce changes aimed at reducing accidents by changing their safety culture and aspects of their safety management. As part of the programme a scientific evaluation was set up to assess the effectiveness of the interventions in 17 of the projects, covering 29 companies. Before and after studies were made of the companies, documenting the state of their safety management and risk control efforts and their accident rates before the intervention, the changes made over the study period and the resulting changes in a range of measures aimed at assessing the success of the changes. The analysis led to a categorisation of the projects according to their degree of success.This paper describes the patterns of interventions distinguishing between successful and not successful projects and discusses the mechanisms lying behind them. Interventions bringing about constructive dialogue between shop-floor and line management, providing motivation to line managers and strengthening the monitoring and learning loops in the safety management system (SM) appeared more successful. The amount of energy and creativity injected by top managers and, above all, by the coordinator (safety professional) appeared also to be a distinguishing factor. 相似文献
82.
Li LZ Zhou DM Peijnenburg WJ van Gestel CA Jin SY Wang YJ Wang P 《Environment international》2011,37(6):1098-1104
The extensive use of nanoparticles (NPs) in a variety of applications has raised great concerns about their environmental fate and biological effects. This study examined the impact of dissolved organic matter (DOM) and salts on ZnO NP dispersion/solubility and toxicity to the earthworm Eisenia fetida. To be able to better evaluate the toxicity of NPs, exposure in agar and on filter paper was proposed for enabling a comparison of the importance of different uptake routes. A dose-related increase in mortality was observed in earthworms exposed in agar with almost 100% mortality after 96 h exposure to the highest concentration (1000 mg ZnO/kg agar). Scanning electron microscopy (SEM) showed that the addition of salts enhanced the aggregation of ZnO NPs in agar and consequently affected the dissolution behavior and biological availability of the particles. On filter paper, mortality was the highest at the lowest exposure concentration (50 mg ZnO/L) and seemed to decrease with increasing exposure levels. TEM images of ZnO showed that the solubility and morphology of NPs were changed dramatically upon the addition of humic acids (HA). The subcellular distribution pattern of Zn in earthworms after 96 h exposure in agar and on filter paper showed that the Zn taken up via dietary ZnO particles (from agar) was mainly found in organelles and the cytosol while the Zn accumulated as soluble Zn from filter paper was mainly distributed in cell membranes and tissues. Antioxidant enzymatic activities (SOD, CAT, and GSH-px) were investigated in the worms surviving the toxicity tests. A slight increase of SOD activities was observed at the lowest exposure dose of ZnO (50mg/kg), followed by a decrease at 100mg/kg in the agar cubes. Activities of both CAT and GSH-Px enzymes were not significantly influenced in the worms exposed to agar, although a slight decrease at 500 and 1000 mg ZnO/kg agar was observed. A similar change trend of SOD activities was observed for the earthworms on filter paper, but a significant decrease began at a higher ZnO NP concentration of 500 mg ZnO/L. The use of soil extracts instead of deionized water (DW) to simulate a realistic exposure system significantly reduced the toxicity of the ZnO NPs on filter paper, which increases the predictive power of filter paper toxicity tests for the environmental risk assessment of NPs. 相似文献
83.
Amit Kapur Hendrik G. van Oss Gregory Keoleian Stephen E. Kesler Alissa Kendall 《Journal of Material Cycles and Waste Management》2009,11(2):155-165
A country-level stock and flow model for cement, an important construction material, was developed based on a material flow
analysis framework. Using this model, the contemporary cement cycle of the United States was constructed by analyzing production,
import, and export data for different stages of the cement cycle. The United States currently supplies approximately 80% of
its cement consumption through domestic production and the rest is imported. The average annual net addition of in-use new
cement stock over the period 2000–2004 was approximately 83 million metric tons and amounts to 2.3 tons per capita of concrete.
Nonfuel carbon dioxide emissions (42 million metric tons per year) from the calcination phase of cement manufacture account
for 62% of the total 68 million tons per year of cement production residues. The end-of-life cement discards are estimated
to be 33 million metric tons per year, of which between 30% and 80% is recycled. A significant portion of the infrastructure
in the United States is reaching the end of its useful life and will need to be replaced or rehabilitated; this could require
far more cement than might be expected from economic forecasts of demand for cement. 相似文献
84.
W. Holländer G. Morawietz D. Bake L. Laskus B. G. van Elzakker A. van der Meulen 《Journal of the Air & Waste Management Association (1995)》2013,63(6):881-886
The European Economic Community Council Directive 80/779/EEC1 describes air quality limit values and guide values for sulfur dioxide and suspended particulates. However, article 10, paragraph 1 does not define well enough the reference method required, amongst others, for the gravimetric measurement of suspended particulates. It is explicity stated in article 10, paragraph 5 of the directive, that “the commission shall, in selected locations in the member states and in cooperation with the latter, carry out studies on the sampling…of suspended particulates. These studies shall be designed in particular to promote the harmonization of methods of sampling and analysis of these pollutants.” Therefore, in a joint research program the Umweltbundesamt (grant #104 02263), the commission of European Communities (grant #84-B-6642-11-017-11-N) and the U.S. EPA (grant #2-43211-3580) funded the development of a reference dust sampler by the Fraunhofer-lnstitute of Toxicology and Aerosol Research (FhITA, in Hannover, Federal Republic of Germany) in order: ? to study the particle size distribution of ambient air aerosol at a number of selected sites; ? to compare the results obtained with the reference dust sampler with those of particle samplers operated in Europe and the United States; ? to verify the applicability of wind tunnel results to sampling behaviour in the free atmosphere. 相似文献
85.
J. Ram Pillarisetti Jeroen C. J. M. van den Bergh 《Environment, Development and Sustainability》2010,12(1):49-62
What is a ‘sustainable nation’ and how can we identify and rank ‘sustainable nations?’ Are nations producing and consuming in a sustainable way? Although several aggregate indexes have been proposed to answer such questions, comprehensive and internationally comparable data are not available for most of these. This paper quantitatively compares three aggregate indexes of sustainability: the World Bank’s ‘Genuine Savings’ measure, the ‘Ecological Footprint,’ and the ‘Environmental Sustainability Index.’ These three indexes are available for a large number of countries and also seem to be the most influential among the aggregate indexes. This paper first discusses the main limitations and weaknesses of each of these indexes. Subsequently, it shows that rankings of sustainable nations and aggregate assessments of unsustainable world population and world GDP shares vary considerably among these indexes. This disagreement leads to suggestions for analysis and policy. One important insight is that climate change, arguable the most serious threat currently faced by humanity, is not or arbitrarily captured by the indexes. 相似文献
86.
J.O. Olowoyo E. van Heerden J.L. Fischer C. Baker 《Atmospheric environment (Oxford, England : 1994)》2010,44(14):1826-1830
Plant and soil have been identified as major sink of pollutants in the environment. We evaluated the reliability of biomonitoring of heavy metals in Tshwane area with the use of leaves of Jacaranda mimosifolia. The concentrations of heavy metals such as Ca, Mg, Fe, Pb, Zn, Cu, Sb were measured in leaves of J. mimosifolia and soils collected from 10 sites in the city of Tshwane during two sampling periods. The metals were analyzed with the use of ICP-MS. The result shows significant differences in the concentration of trace metals in all the sites (p < 0.01). The differences between the two sampling periods were statistically significant (p < 0.01). Concentration of metals from high traffic and industrial sites were significantly higher than in the residential areas (p < 0.01). Concentration factor suggests that translocation of metals from roots to leaves could be relevant only for some metals such as Ca, Mg and Sb. The study reveals an anthropogenic source for the trace metals. Leaves of J. mimosifolia were found to be a useful biomonitor of the determined trace metals. 相似文献
87.
M.J. Metzger R.G.H. Bunce M. van Eupen M. Mirtl 《Journal of environmental management》2010,91(6):1357-1365
Integration of European long term ecosystem research (LTER) would provide important support for the management of the pan-European environment and ecosystems, as well as international policy commitments. This does require appropriate coverage of Europe and standardised frameworks and research methods between countries. Emerging interest in socio-ecological systems prompted the present assessment of the distribution of LTER activities across European socio-ecological gradients. This paper presents a European stratification with a 1 km2 resolution, delineating 48 broad socio-ecological regions. The dataset is based on an existing biogeophysical stratification constructed using multivariate clustering of mainly climatic variables and a newly developed socio-economic stratification based on an economic density indicator. The coverage of European LTER facilities across the socio-ecological gradients is tested using this dataset. The analysis shows two strong biases in the present LTER effort. Firstly, urban and disturbed regions are consistently under-represented, illustrating a bias for traditional ecological research away from human activity. Secondly, the Mediterranean, for which some of the most extreme global change impacts are projected, is receiving comparatively little attention. Both findings can help guide future investment in the European LTER network – and especially in a Long Term Socio-Ecological Research (LTSER) component– to provide a more balanced coverage. This will provide better scientific understanding of pan-European environmental concerns and support the management of natural resources and international policy commitments in the European Union. 相似文献
88.
Juan M. González Benítez J. Neil Cape Mathew R. Heal Netty van Dijk Alberto Vidal Díez 《Atmospheric environment (Oxford, England : 1994)》2009,43(26):4087-4094
Water soluble organic nitrogen (WSON) compounds are ubiquitous in precipitation and in the planetary boundary layer, and therefore are a potential source of bioavailable reactive nitrogen. This paper examines weekly rain data over a period of 22 months from June 2005 to March 2007 collected in 2 types of rain collector (bulk deposition and “dry + wet” deposition) located in a semi-rural area 15 km southwest of Edinburgh, UK (N55°51′44″, W3°12′19″). Bulk deposition collectors are denoted in this paper as “standard rain gauges”, and they are the design used in the UK national network for monitoring precipitation composition. “Dry + wet” deposition collectors are flushing rain gauges and they are equipped with a rain detector (conductivity array), a spray nozzle, a 2-way valve and two independent bottles to collect funnel washings (dry deposition) and true wet deposition. On average, for the 27 weekly samples with 3 valid replicates for the 2 types of collectors, dissolved organic nitrogen (DON) represented 23% of the total dissolved nitrogen (TDN) in bulk deposition. Dry deposition of particles and gas on the funnel surface, rather than rain, contributed over half of all N-containing species (inorganic and organic). Some discrepancies were found between bulk rain gauges and flushing rain gauges, for deposition of both TDN and DON, suggesting biological conversion and loss of inorganic N in the flushing samplers. 相似文献
89.
Mechanistic effect models for ecological risk assessment of chemicals (MEMoRisk)—a new SETAC-Europe Advisory Group 总被引:1,自引:1,他引:0
90.
van den Brink PJ den Besten PJ bij de Vaate A ter Braak CJ 《Environmental monitoring and assessment》2009,152(1-4):271-281
Although chemical and biological monitoring is often used to evaluate the quality of surface waters for regulatory purposes and/or to evaluate environmental status and trends, the resulting biological and chemical data sets are large and difficult to evaluate. Multivariate techniques have long been used to analyse complex data sets. This paper discusses the methods currently in use and introduces the principal response curves method, which overcomes the problem of cluttered graphical results representation that is a great drawback of most conventional methods. To illustrate this, two example data sets are analysed using two ordination techniques, principal component analysis and principal response curves. Whereas PCA results in a difficult-to-interpret diagram, principal response curves related methods are able to show changes in community composition in a diagram that is easy to read. The principal response curves method is used to show trends over time with an internal reference (overall mean or reference year) or external reference (e.g. preferred water quality or reference site). Advantages and disadvantages of both methods are discussed and illustrated. 相似文献