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131.
Environmental Science and Pollution Research - Nanoparticles (NPs) have been progressively applied in the last decades, which may impact the environment. Synthesis of pigments, growing, and...  相似文献   
132.
Environmental Science and Pollution Research - High soil copper (Cu) concentrations in vineyards can cause phytotoxicity to grapevine rootstocks. In order to mitigate toxicity, the use of grapevine...  相似文献   
133.
When large structures such as residential compounds or public buildings are under the influence of extremely low frequency (ELF) magnetic fields, such as the one generated by a system of railways fed by 16.67 Hz, standard methods of designing shielding structures by numerical methods usually fail. The latter can be explained by the difficulty posed in the computing process by the large aspect ratios involved due to thin layers of metal (a few millimetres or centimetres) in contrast to the large dimensions of the affected structure (several tens of meters). In some cases one has to utilize special approximations such as surface conductivity, which are not easy to handle when the designed shielding structure is clearly three -dimensional. Other alternatives such as experimentation in situ are very costly. Here, a new technique is presented of mitigating the field by using three-dimensional propagation of induced currents optimizing the field reduction factors and minimizing the cost of shielding material. The particular designing method is a hybrid of numerical simulations combined with lab experimentation using scaled models of the large structure. The method is rather cost-effective and flexible as various designs can be easily tested. Results are presented in the form of magnetic field values, at various locations in the buildings, before and after this mitigation technique is applied.  相似文献   
134.
In this work a comparative bioadsorption study between a biocomposite consisting of hydrolysed vineyard pruning waste entrapped in calcium alginate spheres and non entrapped vineyard residue was carried out.Results have demonstrated that the biocomposite based on lignocellulose-calcium alginate spheres removed 77.3% of dyes,while non entrapped lignocellulose eliminated only removed 27.8% of colour compounds.The experimental data were fitted to several kinetic models(pseudo-first order,pseudo-second order,Chien–Clayton model,intraparticle diffusion model and Bangham model); being pseudo-second order the kinetic model that better described the adsorption of dyes onto both bioadsorbents.In addition,a morphological study(roughness and shape) of alginate-vineyard biocomposite was established under extreme conditions,observing significant differences between hydrated and dehydrated alginate-vineyard biocomposite.The techniques used to carry out this morphological study consisted of scanning electron microscopy(SEM),perfilometry and 3D surface analysis.  相似文献   
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Environmental Science and Pollution Research - This work investigated an innovative alternative to improve municipal wastewater treatment plant effluent (MWWTP effluent) quality aiming at the...  相似文献   
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Environmental Science and Pollution Research - Nanotechnology has been studied on environmental remediation processes to foster greater photocatalysts efficiency and reuse in wastewater. This study...  相似文献   
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Environmental Science and Pollution Research - The relationship between green innovation and environmental regulations has received increasing attention from researchers, gaining prominence both in...  相似文献   
138.
This research addresses the need to improve our knowledge on the demand for national forests for recreation and offers an in-depth data analysis supported by the complementary use of count data and ordered models. From a policy-making perspective, while count data models enable the estimation of monetary welfare measures, ordered models allow for the wider use of the database and provide a more flexible analysis of data. The main purpose of this article is to analyse the individual forest recreation demand and to derive a measure of its current use value. To allow a more complete analysis of the forest recreation demand structure the econometric approach supplements the use of count data models with ordered category models using data obtained by means of an on-site survey in the Bussaco National Forest (Portugal). Overall, both models reveal that travel cost and substitute prices are important explanatory variables, visits are a normal good and demographic variables seem to have no influence on demand. In particular, estimated price and income elasticities of demand are quite low. Accordingly, it is possible to argue that travel cost (price) in isolation may be expected to have a low impact on visitation levels.  相似文献   
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