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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 205: 649-660, 2018 Dec 05.
Article in English | MEDLINE | ID: mdl-30099216

ABSTRACT

This work covers some physical properties of Sr-doped NiO sprayed thin films at various concentrations (0 to 4%) prepared on glass substrates. Structural properties by using X-ray diffraction (XRD) show that all films have a cubic structure with (111) orientation. The stress, estimated by adjusting the XRD diffraction peaks increases with the doping concentration. Also, the grain size decreases with the doping concentration. On the other hand, the stacking fault probability has been discussed in terms of Sr doping level. The surface morphology of NiO:Sr thin films were examined by AFM observations. The optical constants (refractive index and extinction coefficient) were obtained by reflectance and transmittance measurements. This optical measurements show that the optical band gap is around 3.8 eV. PL measurements show mainly the transition band in UV blue and green domains related to the band-to-band transition and some defects in these prepared thin films. Finally, the advances in the actively studied photocatalysts that are emerging as effective alternate for nickel oxide based photocatalysts is also discussed.

2.
Article in English | MEDLINE | ID: mdl-28486202

ABSTRACT

Metal transition doped oxide thin films or nanocomposites have recently emerged at the forefront of potentials research. With the focus mainly on efficiency, the aspect of stability against optical irradiation of such materials has so far not been thoroughly addressed. This work covers the synthesis of silver doped lanthanum oxide thin films (La2O3:Ag) which have been prepared by the spray pyrolysis technique on glass substrates at 460°C. Then, Ag thin films were grown on lanthanum oxide thin films by thermal evaporation. The present work aims to reach the synthesis of La2O3:Ag thin films using both the spray pyrolysis and thermal evaporation techniques. First, X-ray diffraction analysis shows that undoped and Ag doped films crystallize in a mixture of hexagonal and cubic phase with crystallites oriented along (001) direction. Raman spectroscopy shows the bands positions corresponding to hexagonal and cubic phases. On the other hand, an attempt regarding their optical properties has been carried out by means of photoluminescence measurements. Second, from electrical conductivity measurements, the activation energy decreases from 1.42 to 1.09eV with the increase of annealing time and the charge carriers are following the CBH model as dominant charge transport mechanism. Finally, the annealing time influences the surface wettability property and transforms La2O3 character from hydrophobic (θ>90°) to hydrophilic (θ<90°).

3.
Ann Burns Fire Disasters ; 26(2): 81-5, 2013 Jun 30.
Article in French | MEDLINE | ID: mdl-24133401

ABSTRACT

Infectious complications of finger-joints in association with hand burns are common and dominated by osteoarthritis. However, this issue has hardly ever been addressed in the literature. This ailment can either be identified while patients with extensive burns are undergoing intensive care, or during patient rehabilitation. In the former instance, it is difficult to recognize because patient sedation means the clinical signs are not obvious. In the latter phase, however, the pain, swelling (tumefaction), stiffness and radiological signs are clear. These infections should be diagnosed as soon as possible in order to preserve the function of the hand.

4.
Environ Monit Assess ; 99(1-3): 127-40, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15641376

ABSTRACT

In the arid regions of Tunisia, considerable investments are being made to maintain the old water harvesting techniques and introduce new ones to capture the scarce amount of rainwater (100 mm to 230 mm annually) for agricultural and domestic purposes. However, no detailed assessment of the multiple effects and the costs and benefits of these techniques have been made so far. This paper summarizes the results of an in depth investigation of the multiple impacts (runoff mobilization, ground water recharge, agro-socio-economic impacts) of the water harvesting works undertaken in the watershed of oued Oum Zessar (southeastern Tunisia). The importance of interdisciplinary and integrated approaches was revealed through this detailed impact assessment and economic evaluation. In fact, the profitability of the water harvesting works depends largely on the criteria chosen. However, further refinements are needed to better include all possible impacts (positive and negative) that occur as a result of the installation of the water harvesting structures.


Subject(s)
Conservation of Natural Resources/economics , Environment , Water Supply/economics , Agriculture , Cost-Benefit Analysis , Desert Climate , Fisheries , Humans , Interviews as Topic , Rain , Tunisia
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