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Comparison of two conventional analytical techniques such as X-ray fluorescence (XRF) and inductively coupled plasma mass spectrometry (ICP-MS) for measuring Pb concentrations in soil samples was achieved using field and laboratory work. Seventy-three samples were collected from urban areas surrounding the large lead smelter at South Australia, as an indicator of the environment impact of smelter activity. Soil Pb concentrations were determined using hand-held XRF analyser under laboratory conditions. ICP-MS analysis on digested soils (using a microwave-assisted nitric acid digestion-extraction) was applied to validate p-XRF data. The analysis showed that Pb concentrations determined by XRF correlated with high linearity with Pb concentrations determined by ICP-MS measurements (R 2 = 0.89). Statistical test (t test) was applied to the data of both methods applied without any significant difference between the two techniques. These results indicated that ICP-MS corroborated XRF for Pb soil measurements and suggests that XRF was a reliable and quick alternative to traditional analytical methods in studies of environmental health risk assessment, allowing for much larger sampling regimes in relatively shorter times and could be applied in the field.  相似文献   
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Natural Hazards - The modelling of drought is of utmost importance for the efficient management of water resources. This article used the adaptive neuro-fuzzy interface system (ANFIS), multilayer...  相似文献   
3.
Geotechnical and Geological Engineering - Adopting a low spatial resolution remote sensing imagery to get an accurate estimation of Land Use Land Cover is a difficult task to perform. Image fusion...  相似文献   
4.
This paper addresses the installation effects of stone columns in soft soils. Focus is made on the lateral expansion of stone material using the vibro displacement and substitution techniques by means of numerical simulations. The behaviour of reinforced soil after stone column installation is investigated to show how the properties of soft soils can be improved prior to final loading. The effect of such an improvement on the prediction of reinforced soil settlement is evaluated. The axisymmetric unit cell model (UCM) served for the comparison between numerical predictions made by the Mohr-Coulomb and hardening soil constitutive laws adopted for the soft soil. An equivalent group of end bearing columns model was investigated in the axisymmetric condition to predict the settlement of reinforced soil by adopting the Mohr-Coulomb constitutive model for soft clay. The reduction of settlements predicted by the unit cell and group of columns models, due the improvement of the Young’s modulus of soft clay, were compared. It is concluded that a significant reduction of settlement is expected when the group of columns model is considered.  相似文献   
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The storage capacity of reservoirs is gradually reduced due to sediment accumulation that causes changes in the area-storage capacity (ASC) curves.Establishing these curves and predicting their future change is an important issue for planners,designers and operators of dams.Many empirical and semiempirical approaches have been suggested for establishing and predicting the future changes for these curves.In this study four empirical and semi-empirical methods were evaluated and three of them were modified to be used for the prediction of changes in the ASC curves due to sedimentation,based on the existing sedimentation survey data for 11 reservoirs in the USK For evaluation,these approaches were reviewed and used to determine sedimentation depth and establishing the ASC curves for the Mosul dam reservoir (MDR),which is the biggest hydraulic structure on the River Tigris in northern Iraq.MDR started operating in 1986 with a storage capacity of 11.11 km3 and a water surface area 380 km2 at normal operation stage (330 m a.s.l.).The results obtained from these methods were evaluated using observed bathymetric survey data that had been collected in 2011 after 25 years of the operation of the dam.The evaluation results showed three methods had presented more accurate results for estimating water depth or sedimentation depth at dam site with percentage error about 1.06-3.30%.Whilst for establishing ASC curves,one method presented good agreement result with survey data.Furthermore,ASC and sedimentation depths at dam site of MDR for periods 50,75,100 and 125 years were estimated using the modified approaches and the area reduction method.The results of the modified methods provided reasonable agreement when compared with the area reduction method proposed by the U.S.Bureau of Reclamation and the agreement became better with an increase in time period.  相似文献   
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