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61.
The RAMseS project, under the European Commission's 6th Framework Program, is dedicated to the construction and test of low-power operations based on photovoltaic power and a multipurpose electric vehicle. In the present study, the life-cycle costs and economical indices for the vehicle during its life span were assessed, compared to those of a standard internal combustion engine vehicle (ICEV). The results indicated that the life-cycle costs for the RAMseS vehicle and the ICEV are the same for a fuel unit price of 1.8 €/L. Also, the levelized cost of energy (LCE) for the RAMseS vehicle, was found to be 2.13 €/kWh, while RAMseS LCE, without EV taken into account, was shown to be 0.62 €/kWh. The RAMseS payback period (PBP) without EV taken into account was calculated to be 9 years if the value of the produced energy becomes at least 0.35 €/kWh. Vehicles that use PV systems as their power source, such as RAMseS, will be economically effective for fuel costs higher than 1.8 €/L, but considering the environmental benefits that are provided in terms of external costs, they can be considered profitable even at lower fuel costs.  相似文献   
62.
Environmental Science and Pollution Research - Aquaculture is one of the fastest-growing industries in the world, and its prominent role has been proven in supplying food for the growing world...  相似文献   
63.
Environmental Science and Pollution Research - To provide the progressive global demand for energy, the use of renewable energies is being rapidly developed. Since solar radiation is available in...  相似文献   
64.
The study of heavy metals’ redistribution between different fractions allows to know their bioavailability and mobility in soils. Soil samples were collected from a lead mine in Hamadan provinces, NW Iran. In a factorial experiment soil was treated with cow, sheep and poultry manures (20?g?kg?1 soil) separately and incubated near field capacity at 10°C and 37°C. An untreated soil (as control) was also incubated at the same temperatures. After 0 and 120 days, a sequential extraction scheme was used to fractionate Pb of incubated samples into soluble-exchangeable (Sol-Exch), organic matter associated (AOM), carbonates associated (ACar), and residual (Res) forms. Soil Pb in Sol-Exch and AOM fractions were increased by manure application significantly. The AOM and ACar forms of Pb were higher in soils treated with the manures and incubated in lower temperature. In contrast, the Sol-Exch and Res chemical forms of Pb were higher in the soils incubated at 37°C. These results may be related to the higher calcium carbonate dissolution and organic matter decomposition because of better biological activity in the soils incubated in higher temperature. The increase of the Res fraction (stable form) in this condition may resulted in lower toxicity and mobility in soil environment.  相似文献   
65.
In this study, kinetics of photocatalytic degradation of phenolic wastewater in immobilized photocatalytic reactor was investigated. Immobilization of titanium dioxide (TiO2) nano powders on concrete surfaces were accomplished with epoxy concrete sealer. Kinetics of photocatalytic reactions has been proposed to follow the Langmuir–Hinshelwood model in different initial phenol concentration, pH, and UV lamp intensity. First-order reaction kinetics with respect to the pollutant concentration was obtained for the reaction. Effect of UV lamp intensity showed that kinetic constants were proportional to the power of 0.73–1 of the photonic flow. In all cases kinetic constant increases as pH of the system reached up to 12 units. Several reaction intermediates were identified using the GC/Mass analysis. Products at the initial stage of the reaction were aromatic compounds, contained hydroquinone, benzoquinone, and catechol. These intermediates underwent further photocatalytic oxidation to aliphatic compounds and finally into CO2 and H2O after 4?h. Kinetic constants of intermediate compounds were determined using mathematical–chemical equations and nonlinear regression. Data showed that the differences between the mathematical model and Langmuir–Hinshelwood model for the kinetic constant was less than 5%.  相似文献   
66.
Carbon nanotubes (CNTs) have found numerous applications in various industries. Recently, adverse effects of these materials on human and animal cells in vitro have been reported. In the present study, the cytotoxicity of single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), and chrysotile asbestos in human lung epithelial cells has been studied using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The cells were exposed for 6 h and 24 h to between 0.97 and 1500 μg mL?1 of CNTs and chrysotile fibers prepared in two culture media containing 5% serum and 0.5% dimethylsulfoxide. Dose–response curves were obtained to determine the nonobservable adverse effect concentration and the half-maximum inhibitory concentration (IC50). The way of dispersion affects the cytotoxicity of CNTs. For MWCNT, the toxicological indexes were lower than for SWCNT. Chrysotile fibers were even less cytotoxic than CNTs. Therefore, workplace control measures are recommended as priority for occupational and environmental conditions.  相似文献   
67.
Environmental Fluid Mechanics - Bends and confluences are often observed in rivers, and one of the phenomena that characterize flows in open channel bends and confluences is secondary current....  相似文献   
68.
69.
In this research work, the rheological properties of Wood-Plastic Composites (WPC) with some selected compositions are investigated. WPC is being recognized as a green composite that, in the past 20?years, has emerged to a commercial product. A study on rheological properties of these materials can give insight into the proper selection of composition and processing condition. Two grades of polypropylene (PP) with two different melt flow indexes (MFI) were selected to prepare WPCs with three different wood contents (50, 60 and 70?% wt.). Four types of rheological experiments were performed utilizing a rotational plate rheometer: (1) strain sweep, (2) frequency sweep, (3) temperature sweep and (4) steady shear rate sweep. The independent variables were chosen as wood content, MFI of polymer (two types), melt temperature, frequency or shear rate, the gap between the plates, and strain percentage. The strain sweep tests specified the linear and non-linear viscoelastic zones of each experiment. The results of frequency sweep experiments indicated that increasing the wood content and frequency and also decreasing the strain percentage and the gap distance, lead to an increase in the storage modulus. Regarding the loss modulus, wood percentage and the gap distance presented positive effects and strain percentage showed a negative effect. The behavior of complex viscosity was almost similar to that of the storage modulus but increasing the frequency caused a decrease in the complex viscosity. In case of temperature sweep experiments, it was observed that the rheological properties exhibit a rapid change near to a temperature of 160?°C. The results also showed that beyond this point, increasing the wood content and also MFI of polypropylene caused an increase in the storage modulus. The results of steady shear rate sweep experiments specified that increasing wood content and also decreasing the MFI of PP, the gap distance and shear rate lead to an increase in both viscosity and shear stress.  相似文献   
70.
Sorption of metal ions by soil and clay minerals is a complex process involving different mechanisms, and controlled by different variables that can interact. The aim of this work was to study the retention mechanisms of Pb ions on different soil samples. Surface soils were sampled from Guilan and Hamadan provinces in north and northwest of Iran with temperate and semiarid climates. The adsorption isotherms of Pb on the soils have been studied at 15, 27 and 37°C. The adsorption data for different soils were fitted into Langmuir and Freundlich models. Temperate soil samples had higher clay content, cation exchange capacity, dichromate (oxidable) organic carbon, total Kjeldahl-nitrogen, biological activity, amorphous and crystalline Fe and Al, but semiarid soil samples had higher sand content, pH, equivalent calcium carbonate, available P and K. Lead adsorption data obtained from semiarid soils against those obtained from temperate soils were better fitted in both Langmuir and Freundlich models. Langmuir constants Q 0 for Pb adsorption in semiarid soils were considerably lower than those for Pb adsorption in temperate soils. However, the binding energy (K L) of Pb and Freundlich constant n were higher for data of semiarid soils. The effect of temperature on the Pb adsorption was positive especially in temperate soils; however, soil properties had higher effects on Pb adsorption.  相似文献   
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