Flow characterization and modelling of a South Benin artesian aquifer system : Effects of hydraulic and storage properties and recharge on simulated heads across the artesian zone

Abstract This work is part of the hydrogeological study of the Kherzet Youcef deposit. The polymetallic deposit of Kherzet Youcef, known, since the beginning of the 20th century, by the exploitation of Lead and Zinc ore, is located 50 Km southeast of Setif (North-eastern Algeria) and 5.5 Km west of Ain Azel. Mineralization is represented by some ore bodies (about 25). The thickness variate from a few centimeters up to 3m. These bodies are located on the layers of dolomites and dolomitized marls and along the Kherzet Youcef fault. The geological reserves of Zinc and Lead ore are of the order of 1.6 million tons. This ore has a Pb content of 3.6% and Zn content of 18.4%. The projected annual exploitation was 100 thousand tons per year. Hydrogeological studies carried out successively (1973-1977) and (1981-1983) revealed the existence of an aquifer system located west of the Kherzet Youssef fault characterized by the presence of Karts and by strong cracking due to local brittle tectonics. These two characteristics define the filtration and storage capacity of very abundant groundwater. This groundwater represented a major handicap for mining in view of the large amounts of water that required the installation of major pumping and drainage devices. The Kherzet Youssef mine has experienced frequent flooding in the past at a time when technology could not pump efficiently. It caused the mine to close several times. In June 1990, the mine experienced a flood of great magnitude that has never been observed and despite the large installed means of pumping, this "water cost" led to the total drowning of the mine, the death of 19 workers and the stoppage of the exploitation of this deposit since. Pitting attempts were carried out with a pumping capacity of 1100 m3/h, then 1800 m3/h but without success. The interpretation of the drawdown data and field observations made it possible to conclude that this accident was only the result of the general destabilization of the massif. Our complementary work by geophysical prospecting made it possible to represent the configuration of the underground layers and demonstrate the hydrodynamic communication between the two East and West compartments of the deposit.

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Effect of Replacing Partial of Wheat Flour by Lentil Powder on Quality Properties of Laboratory Bread

Baghdad Science Journal ◽

10.21123/bsj.9.3.406-410 ◽

2012 ◽

Vol 9 (3) ◽

pp. 406-410

Author(s):

Baghdad Science Journal

Keyword(s):

Chemical Analysis ◽

Sensory Evaluation ◽

Wheat Flour ◽

Lens Culinaris ◽

External Layer ◽

Quality Properties ◽

White Flour ◽

And Storage ◽

Storage Properties

This investigation was carried out to examine the effect of replacing partial of flour by dried Lentils (Lens culinaris) to white flour in different percentages on the chemical, sensory and storage properties of the Laboratory bread. The results revealed that replacing 0% than wheat flour by lentil powder (1) control was high significan than the replacing 25 and 35% than wheat flour by lentil powder ( 4 and 5) in flavor and chewiness . The results of sensory evaluation showed that replacing 4 were high significan different than that of replacing 1 in external layer colour. Other replacing percentages, however, did not show significant differences of in comparison with control . In regards with chemical analysis of Iron and copper, it was increased as replacing percentages increased of the bread. Regarding replacig 5% (2 ) than wheat flour by lentil powder gained higher score of overall acceptance than other replacing percentages . Replacing 5 gained higher score of overall acceptance than replacing 15% (3) and 4 . It can be concluded that the best replacing from the overall acceptance of bread was 5% than wheat flour by lentil powder ,and retained its softness and flavor at - 8°c for 7 days in comparison with replacing 1 . and replacing in 5 that the best from the overall acceptance in comparison with replacing in 3 and 4 . and in percentages of Iron and copper in comparison with other replacing percentages It may be concluded that anemia people can get from consumption of this bread which is acceptable when 35 % powders were added.

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Nano-Columnar Mg Thin Films Created by Plasma Sputter Deposition for Improved Hydrogen Kinetics and Storage Properties

MRS Proceedings ◽

10.1557/proc-837-n1.3 ◽

2004 ◽

Vol 837 ◽

Cited By ~ 1

Author(s):

M. W. Zandbergen ◽

S. W. H. Eijt ◽

W. J. Legerstee ◽

H. Schut ◽

V. L. Svetchnikov

Keyword(s):

Thin Films ◽

Hydrogen Storage ◽

Hydrogen Permeation ◽

Hydrogen Desorption ◽

Sputter Deposition ◽

Hydrogen Molecules ◽

Concomitant Reduction ◽

And Storage ◽

Determining Factor ◽

Storage Properties

ABSTRACTThe hydrogen storage properties of nanostructured Mg and MgH2 thin films were studied as created by Ar and Ar+H2 plasma sputter deposition. Columnar structures with typical widths of ∼120 nm are observed with their long columnar axis extending throughout the thickness of the films. Applying substrate bias voltages during deposition results in narrower columns. A concomitant reduction in hydrogen desorption temperature from 400 °C to 360 °C is observed. Capping the Mg films with a ∼100 nm thin Pd layer leads to significantly reduced hydrogen desorption temperatures of ∼200 °C induced by the catalytic activity of the Pd cap layer. Also, hydrogen permeation of the films is strongly improved. The rate-determining factor is found to be the dissociation of the hydrogen molecules. Optimum hydrogen loading conditions of the Pd/Mg films were obtained just above ∼200 °C at hydrogen pressures of 0.25–1.0 MPa, resulting in hydrogen storage capacities in the range of 4–7 wt%.

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