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911.
912.
This study was conducted to determine the most appropriate surface processing techniques (SPT), environmental conditions (EC) and surface roughness (SR) to minimize the risk of slipping when pedestrians walk on a floor covering of rocks barefoot and with shoes. Coefficients of friction (COFs) and values of SR were found using five different types of rocks, four SPT and two (ramp and pendulum) tests. Results indicate that the parameters which affect the COF values of rocks include SR, EC and SPT. Simple linear regression was performed to examine the relationship between the values of the COF and the SR. The value of the COF was identified as R2?≥?0.864. Statistical results, which are based on experimental measurements, show that rocks are classified according to their safe use areas depending on their COF and SR values.  相似文献   
913.
This paper describes an integrated approach to transform an industrial park into an eco-industrial park by combining three interconnected goals, namely, the consolidation of industrial symbiosis, the promotion of sustainable accessibility and the development of multi-functionalities. The result is an interdependent approach where industrial and territorial ecosystems are jointly planned, seeking a more sustainable level of development that considers industrial activity, the transportation of people and goods and the spatial articulation with the neighbouring environment and urban areas. The critical points and challenges for improving the territorial integration of the French industrial park of Salaise-Sablons are discussed, providing lessons for the future. Regardless of the specificities of the case study, this approach has the potential to be adopted in similar industrial parks.  相似文献   
914.
Fisheries are an important source of food, with a high economic value and social significance. The present worrying situation of the world fisheries is the result of the interaction between different factors (e.g. climatic variations, natural oscillations, technological innovation), but the greatest challenges are overfishing and climate change. The species richness of the Portuguese coast is generally higher than that found in northern Europe and similar to that of the Mediterranean, since many species have their southern or northern distribution limits along the Portuguese coast. The zoogeographic importance of this latitudinal area has long been recognized, representing the transition between north-eastern Atlantic warm-temperate and cold-temperate regions, which makes the Portuguese coast an area of great sensitivity to the detection of climate change. Official landing data for commercial species that have the Portuguese coast as their distribution limit were analysed together with sea surface temperature for the period of 1927–2011. In general, landings of species with affinity for temperate waters presented a decreasing trend, whereas species with affinity for subtropical/tropical waters showed an increasing trend. These variations were associated with variation in temperature: lower landings of temperate species occurred mainly in warm years, whereas landings of subtropical/tropical species presented an opposite trend, with higher landings in warm years. Preparing for the impacts of climate change is crucial for the sustainability of fisheries. Management should take into consideration information about environmental factors that affect species distribution and abundance.  相似文献   
915.
Wave hydrodynamics around a multi-functional artificial reef at Leirosa   总被引:1,自引:0,他引:1  
This paper describes an application of the Boussinesq-type COULWAVE model to study the wave hydrodynamics in the vicinity of a multi-functional artificial reef (MFAR). This reef is under investigation and consists of a supplementary protection solution for the Leirosa sand dune system located at South of Figueira da Foz, on the Portuguese West coast. Such installation near the coastline is expected to contribute to enhance the surfing conditions in the area, protect the sand dune system in the surroundings of Leirosa beach, and increase its environmental value. Numerical calculations with the COULWAVE model were performed for four test cases, considering two reef geometries (differing in the reef angle) and two incident wave conditions (storm condition and a common wave condition). Comparisons between the results obtained, in terms of wave heights and breaking line positions allow us to assess the influence of the reef on the hydrodynamics near the beach and around the reef. Moreover, the reef performance was analysed in terms of surfability and coastal protection. The surfability parameters (breaker height, Iribarren number and peel angle) were calculated for each test case using the numerical wave heights, wave directions and wave breaking positions. Comparisons of parameters allow characterizing the most appropriate configuration of the reef to improve the surfing conditions in the study area. A methodology based on numerical free surface elevations and horizontal velocity components was developed to calculate wave directions, since this is not a direct output of the COULWAVE model. Concerning coastal protection, analyses of the mean currents around the reef were used together with observations of the velocity cells near the shoreline as an indication of the sediment transport.  相似文献   
916.
In spite of its outstanding ecological and touristic importance the Ria Formosa Lagoon shows signs of anthropogenic pollution. Nonetheless, until the present survey no studies had ever documented the measurement of natural and pharmaceutical estrogens (17β-estradiol, estrone, and 17α-ethynylestradiol), xenoestrogenic industrial pollutants (4-octylphenol, 4-nonylphenol, and their mono and diethoxylates and bisphenol A), phytoestrogens (formononetin, biochanin A, daidzein, genistein), and sitosterol in this area. The 17 compounds measured herein are known as endocrine disrupters (EDCs) and act over the endocrine system even in few amounts (ng L?1–μg L?1). Thus to conclude about the influx of EDCs in the lagoon, water samples were taken every 2 months, during 1 year (2010), in low tide at nine sites distributed along the coastline. Water samples (1 L) were preconcentrated in the Oasis HLB cartridges and cleaned in silica cartridges before their analysis by GC-MS. Data showed the ubiquitous presence of potentially hazardous amounts of estrogens (particularly of ethynylestradiol, up to 24.3 ng L?1), nonylphenol (up to 547 ng L?1), and sitosterol (up to 12,300 ng L?1), mainly in summer, suggesting that the increase of the local number of inhabitants (tourists), the rise of the water temperature (up to 26 °C), and the blooming of local flora may interfere with the water quality parameters. This makes the lagoon a potential model to study. Taking into account the data, it was concluded that there are conditions for the occurrence of endocrine disruption in aquatic animals, even in areas included in the natural park of the Formosa. Besides, both the high amounts of un-ionized ammonia (up to 0.3 mg L?1) and phosphates (up to 1.6 mg L?1) my pose risks for local fauna and humans.  相似文献   
917.
918.
In this study, we present evidence of lead in lip liner, oil absorbent powder, mascara, concealer, lipsticks, lip gloss, and foundation. The samples were analyzed for lead by flame atomic absorption spectrometry. The levels of lead in concealer, mascara, lip liner, and oil absorbent powder were found to be 7.4?±?1.3?µg?g?1, 15.8?±?0.2?µg?g?1, 29.0?±?9.2?µg?g?1, and 17.3?±?2.9?µg?g?1, respectively. The levels of lead in lipsticks, lip gloss, and foundation ranged from not detected to 73.1?±?5.2?µg?g?1, 4.7 to 11.7?±?2.8?µg?g?1, and 7.8 to 32.9?±?1.4?µg?g?1, respectively. Thus, in the majority of samples, the concentrations of lead are higher than the USFDA maximum permissible concentration of 0.10?µg?g?1 in candy and cosmetics. In lipsticks alone, only 25% of 40 samples were found to meet the requirement. Therefore, continuous use of cosmetic products in which lead concentration exceeds the maximum permissible level may pose a health hazard for the female population of South Africa in the long run.  相似文献   
919.
Plankton samples were collected from different parts of the Liguro-Provençal Basin during 1979 and 1980 (nearshore and open waters, respectively). Carbon, nitrogen, phosphorus, silicium, aluminium, iron, manganese, zinc, copper, cadmium and mercury concentrations have been determined in these samples. The species composition of plankton has been studies. The results indicated that species composition as well as sampling dates and location are factors of great importance when considering the chemical composition of plankton. Carbon, nitrogen and phosphorus concentrations display variations, but their ratios appear to be almost constant in the various samples. The other elements, except zinc, seem to be less concentrated in plankton from open waters than from coastal waters. The concentrations found are in good agreement with those reported in the literature by various authors.  相似文献   
920.
The content of 21 organochlorine pesticides were studied in vegetation samples of a highly contaminated area by isomers of hexachlorocyclohexane (HCH) located close to a former industrial area in Galicia (NW Spain). Five species of plants were collected at different points of the contaminated area and the different parts of the plants were separated in order to study differences in accumulation capabilities. Samples were extracted employing microwave energy followed by a clean-up step using solid phase extraction and finally determined by GC–ECD. The results obtained show that the most abundant pesticides are HCHs isomers, being the main isomers β-HCH and -HCH in all samples whereas δ-HCH and γ-HCH were at lower levels. Some other pesticides such as p,p′-DDT, p,p′-DDD and p,p′-DDE were also present in much lower amount in some of the samples. Several degradation products of HCH were also identified in some samples by GC–MS.  相似文献   
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