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Bessenasse M.,Blida University | Bessenasse M.,Laboratory Research of science of Water | Kettab A.,Polytechnic School of Algiers | Moulla A.S.,Algiers Nuclear Research Center
Desalination | Year: 2010

According to recent demographic statistical data, the number of inhabitants in Algeria should double in the next thirty years whereas availability of water resources will not change. The hydrologic situation especially for the coastal areas reflects severe drought conditions that are lasting since two decades. Seawater desalination could be an efficient alternative in order to mitigate the forecasted serious water shortage crisis. In fact, due to rural depopulation a large majority of the people and the economic activities are nowadays concentrated in the coastal cities of the Mediterranean coast along ~ 1200 km. The good physical and chemical features of Mediterranean seawater (19 °C and medium salinity as compared to that of Persian Gulf which exhibits 30 °C and much higher salinity) make of Mediterranean desalination plants more profitable with less operating costs and better efficiencies. Reverse osmosis has been chosen as the best desalination process because it has seen many technological improvements especially with regard to better performance and longer membranes lifetimes. The present study focuses on three small desalination plants located not far from the capital city of Algeria (Algiers) namely: Palm-beach sea resort, la Fontaine and Bou-Ismaïl. Our main objective was directed towards the evaluation of the cost of the chemical consumables and the overall cost of the desalinated cubic meter of water. The latter was found lower than 0.5 €, which is quite interesting. All in all, the desalination option seems to be a good alternative to deal with the most urgent matters in terms of ensuring durable water allocation in the climatic context prevailing nowadays. © 2009 Elsevier B.V. Source

Kaci S.,Silicon Technology Development Unit | Keffous A.,Silicon Technology Development Unit | Guerbous L.,Algiers Nuclear Research Center | Trari M.,University of Science and Technology Houari Boumediene
Thin Solid Films | Year: 2011

PbS nanoparticles and smooth nanocrystalline thin films (nc-PbS) were prepared by chemical precipitation from aqueous solutions. Polyethylene oxide and isopropyl alcohol were used as additives in the aqueous solution, which results in the enhancement of the blue luminescence of PbS thin films. The introduction of isopropyl reduced the grain size and increases the optical gap of the PbS particles. The size of PbS particles was estimated to be ~ 3.5 nm. The broad emission bands exhibited were composed by a multiple overlapping peaks. The photoluminescence (PL) intensity was significantly influenced by the excitation wavelength. Indeed, intense blue luminescence was obtained under 230 nm compared to that obtained under 325 nm excitation wavelength. The PL emission from PbS nanoparticles was less intense than the luminescence of PbS thin films. The high PL intensity of the thin films was attributed to the lower density of defects introduced in the thin films during the chemical bath deposition growth process compared the defects density of PbS powder. © 2011 Elsevier B.V. Source

Kaci S.,Silicon Technology Development Unit 2 | Keffous A.,Silicon Technology Development Unit 2 | Trari M.,University of Science and Technology Houari Boumediene | Fellahi O.,Silicon Technology Development Unit 2 | And 3 more authors.
Journal of Luminescence | Year: 2010

Thin films of lead sulfide (PbS) nanoparticles were grown on corning glass and Si(1 0 0) substrates by polyethylene glycol-assisted chemical bath deposition (CBD) method. This paper compares the morphology and the luminescence properties (PL) of the deposited thin films in the presence (or absence) of PEG300 and investigates the effect of deposition temperatures. Surface morphology and photoluminescence properties of samples were analyzed. The PL data show a blue-shift from the normal emission at ∼2900 nm in PbS bulk to ∼360 nm in nanoparticles of PbS thin films. Furthermore, the PL emission of the films obtained without the addition of PEG300 (type 1) was slightly shifted from that of the films obtained in presence of PEG300 (type 2) from ∼360 to ∼470 nm. The blue-shifting of the emission wavelengths from 2900 to ∼360 or 470 nm is attributed to quantum confinement of charge carriers in the restricted volume of nanoparticles, while the shift between the two types of PbS nanoparticles thin films is speculated to be due to an increase in the defect concentration. The blue-shift increased with increase of the deposition temperature, which suggests that there has been a relative depletion in particle sizes during the CBD of the films at higher temperatures. The PbS nanocrystalline thin films obtained in the presence of PEG300 at 60 °C exhibit a high blue luminescence. © 2010 Elsevier B.V. All rights reserved. Source

Beladel B.,Ziane Achour University of Djelfa | Nedjimi B.,Ziane Achour University of Djelfa | Mansouri A.,Algiers Nuclear Research Center | Tahtat D.,Algiers Nuclear Research Center | And 4 more authors.
Applied Radiation and Isotopes | Year: 2013

In this work, we have measured the selenium content in wheat produced locally in eight different regions of Algeria from east to west, and we have established the annual consumption of selenium for five socio-professional categories. Instrumental neutron activation analysis is used. The selenium levels in wheat samples varied from 21 (Tiaret) to 153. μg/kg (Khroub), with a mean value about 52. μg/kg. The mean of selenium daily consumption from ingestion of wheat per person in the eight regions varied from 32 to 52. μg/day which is close to the minimal FAO recommendation. © 2012 Elsevier Ltd. Source

Saibi H.,Kyushu University | Mesbah M.,Sudan University of Science and Technology | Moulla A.S.,Algiers Nuclear Research Center | Guendouz A.H.,Blida University | Ehara S.,Kyushu University
Environmental Earth Sciences | Year: 2016

Oued-Souf City, located in the northwestern part of Algeria, has rapidly grown and been urbanized. The city and surrounding areas depend heavily on groundwater as a water source for drinking, as well as domestic, industrial, and agricultural uses. Comprehensively understanding the chemistry of the groundwater provides insight into the interaction of water with the environment and contributes to better overall resource management. The phreatic groundwaters are SO4–Ca in character. These waters are hard with a high salinity, which poses a distinct danger for plants. Furthermore, major chemical elements in the water have concentrations above the values recommended by World Health Organization. The phreatic groundwaters display bacteriological germs in sampled waters, and high concentrations of nitrates were detected in the samples due to the absence of a formal sanitation network. In this work, stable and radioactive isotopes are used to understand the water origin of the phreatic groundwaters. The present isotopic study suggests that the groundwaters from the Oued-Souf phreatic aquifer are composed of two primary components, one from infiltrating recent rain waters and the other one from deep captive groundwaters. Herein, descriptive statistics, correlation matrices, and factor analyses were employed to understand the hydrochemistry of the groundwater in the phreatic aquifer in the Oued-Souf area. © 2015, Springer-Verlag Berlin Heidelberg. Source

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