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91.
92.
Physical and chemical characterization of spent oil shale (OS) from El-Lajjun area has been carried out and compared with
the original OS. The spent shale (SS) is subjected to leaching tests to detect the possibilities of heavy metals released
from it into the environment. Standard column leaching experiments have revealed no detectable release of heavy metals to
the percolating water. The effectiveness of the SS in removing Pb2+ from wastewater has been investigated. The SS is very efficient in removing most of Pb2+ where 1 m3 of SS has an efficiency to remove from 64 to 94% of Pb2+ from about 1,300 m3 wastewater sample containing 50 ppm Pb2+. The efficiency decreases substantially with increasing Pb2+ concentration in the wastewater. In real situations, where Pb2+ concentration is very low (i.e., less than 5 ppm), the efficiency of the SS is expected to be 100%. 相似文献
93.
For many years, the Dead Sea suffers from an annual inflow deficiency of about one billion cubic meters, flood and baseflow. The water level changes are related to the majority of surface water inflows diverted for irrigation purposes, in addition to intensive loss of water by the high rate of evaporation and industrial water use. This causes the Dead Sea water level to decline about 35 m within the last 50 years for a long-term average of about 0.79 m per year. The changes in the hydrochemical composition were simulated experimentally to determine the changes that take place as a function of brine water evaporation level and its density. The Total Dissolved Solids (TDS) and the density of the Dead Sea water varies as a function of its water evaporation level changes. It was found that the density variation is not following a linear function with respect to water volume changes. But it follows the total amount of precipitate that occurred at different water levels. The electrical conductivity (EC) changes with respect to time and the prevailing temperature. There was no formula to calculate the high salinity of brine water above the normal ocean water. Consequently, the EC measurements were adopted to represent the Dead Sea water salinity. But in this research a converging factor (0.80971) has been found to convert the TDS values into salinity values. On contrary, the pH values revealed an inverse relationship with respect to the evaporation levels. 相似文献
94.
A quantitative interpretation method of self-potential field anomalies has been proposed. The method is designed and implemented for the estimation of center depth, electric dipole moment or magnitude of polarization, polarization angle, and geometric shape factor of a buried body from SP field data, related to simple geometric structures such as cylinders, spheres and sheet-like bodies. The proposed method is based on Fair function minimization and also on stochastic optimization modeling. This new technique was first tested on theoretical synthetic data randomly generated by a chosen statistical distribution from a known model with different random noise components. Such mathematical simulation shows a very close agreement between assumed and estimated model parameters. Being theoretically proven, it has been applied and tested on self-potential field data taken from the United States, Germany, India and Turkey. The agreement between results obtained by the suggested method and those obtained by other previous methods is good and comparable. Moreover, the depth obtained by this method is found to be in high accordance with that obtained from drilling information. 相似文献
95.
Trend analysis of water discharge and sediment load during the past three decades of development in the Langat basin,Malaysia 总被引:1,自引:0,他引:1
Abstract In this study, the trends of water discharge and sediment load from three hydrometric stations over the past 25 years of development in the state of Selangor, Peninsular Malaysia, were analysed using the Mann-Kendall and Pettitt tests. Landscape metrics for establishing the relationship between land-use changes and trends of hydrological time series were calculated. The hydrological trends were also studied in terms of rainfall variations and manmade features. The results indicate upward trends in water discharge in the Hulu Langat sub-basin and in sediment load in the Semenyih sub-basin. These increasing trends were mainly caused by rapid changes in land use. Upward trends of hydrological series in the Hulu Langat sub-basin matched its rainfall pattern. In the Lui sub-basin, however, trends of hydrological series, and variations in rainfall and land use were not statistically significant. Editor Z.W. Kundzewicz; Associate editor K. Hamed Citation Memarian, H., Balasundram, S.K., Talib, J.B., Sood, A.M., and Abbaspour, K.C., 2012. Trend analysis of water discharge and sediment load during the past three decades of development in the Langat basin, Malaysia. Hydrological Sciences Journal, 57 (6), 1207–1222. 相似文献
96.
Fadi Chaaban Hanan Darwishe Barbara Louche Yvonne Battiau-Queney Eric Masson Jamal El Khattabi Erick Carlier 《Environmental Earth Sciences》2012,65(1):183-193
The use of geographic information system (GIS) minimizes the effort and improves the efficiency of numerical models. The GIS
provides a platform for high capacity collection, management, manipulation, analysis, modeling and display of spatial data.
The conceptual model is created using GIS objects including points, arcs and polygons so that it can accurately represent
real world condition. According to the research problem, the geographical model is based on Hypergraph Based Data Structure
method, and a conceptual data model has been created from which a physical data model was elaborated in ArcGIS9.3 platform.
The groundwater modeling system (GMS) provides a powerful tool for hydrodynamics modeling and it is able to solve complex
problems such as the groundwater flow and seawater intrusion. The sand-dune system of Hardelot-Plage (North of France) suffers
from a lack of well-developed foredune. This problem is linked to the almost constant saturation of beach sand which is the
potential source of dune nourishment. In the south of Hardelot, the coastline is slowly, but constantly retreating. To remedy
this situation, a coupling between a GIS and GMS was adopted, in order to find the possible scenarios which could lower the
piezometric surface in the concerned area and allow dune nourishment again. The GMS used supports the Modflow-2000 code. A
direct approach to designing Modflow finite difference model is tedious and less intuitive, specifically for complex boundary
and initial conditions. Therefore, a Modflow model can be developed either using a grid or conceptual model approach. The
preparation of input data modeling is tedious and takes a long time. The model created in GMS was calibrated against the historical
and observed water level data for 1995–2006. Then a hydrodispersive model (MT3d code in GMS) was launched for evaluating sea-water
intrusion. The model was run to generate groundwater and salt concentration scenario during pumping tests. 相似文献
97.
Continuous Monitoring of Pin Tip Wear and Penetration into Rock Surface Using a New Cerchar Abrasivity Testing Device 总被引:1,自引:0,他引:1
Mohammad-Taghi Hamzaban Hossein Memarian Jamal Rostami 《Rock Mechanics and Rock Engineering》2014,47(2):689-701
Evaluation of rock abrasivity is important when utilizing mechanized excavation in various mining and civil projects in hard rock. This is due to the need for proper selection of the rock cutting tools, estimation of the tool wear, machine downtime for cutter change, and costs. The Cerchar Abrasion Index (CAI) test is one of the simplest and most widely used methods for evaluating rock abrasivity. In this study, a new device for the determination of frictional forces and depth of pin penetration into the rock surface during a Cerchar test is discussed. The measured parameters were used to develop an analytical model for calculation of the size of the wear flat (and hence a continuous measure of CAI as the pin moves over the sample) and pin tip penetration into the rock during the test. Based on this model, continuous curves of CAI changes and pin tip penetration into the rock were plotted. Results of the model were used for introduction of a new parameter describing rock–pin interaction and classification of rock abrasion. 相似文献