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Mhadhbi M.,National Institute of Research and Physicochemical Analysis | Sunolb J.J.,University of Girona | Khitouni M.,University of Sfax
Physics Procedia | Year: 2013

A nanocrystalline Fe(Al) solid solution was prepared by mechanical alloying (MA) of Fe and Al elemental powders using a planetary ball mill under argon atmosphere. The powder milled for 20 h was annealed at 250, 550 and 650 °C for 1 h. The phase transformations and structural changes occurring in the studied material during mechanical alloying and during subsequent annealing were investigated by X-ray diffraction. The morphology of the powders after MA was examined via SEM and TEM. © 2013 The Authors. Published by Elsevier B.V.


Alfeeli B.,Kuwait Institute for Scientific Research | Al-Rawashdeh M.,TU Eindhoven | Bumajdad A.,Kuwait University | Lawati H.A.,Sultan Qaboos University | And 4 more authors.
Nanotechnology Reviews | Year: 2013

A growing number of initiatives on nanotechnology research, education, and industry have been recently launched by several Arab countries to quickly build scientific capacity and track worldwide developments in nanotechnology. Some countries, namely, the oil-rich countries, have allocated large funds to support these initiatives, which are intended to serve the national interests in energy, water and food supply, medicine, and local industry. The other Arab countries are also pursuing nanotechnology, however, with fewer funds but with more human resources. This study assesses the current status of nanotechnology in the Arab Republic of Egypt, Hashemite Kingdom of Jordan, Kingdom of Morocco, Kingdom of Saudi Arabia, Republic of Tunisia, State of Kuwait, State of Qatar, Sultanate of Oman, and the United Arab Emirates (UAE). The study is aimed at having a top-level overview of the status of existing, underdevelopment, and planed educational and research programs relevant to nanotechnology. The overview also includes nanotechnology research focus areas, challenges, and opportunities.


PubMed | Tunisian National Institute of Applied Sciences and Technology, National Center for Nuclear Science and Technology, National Institute of Research and Physicochemical Analysis and National Institute of Research and Physico chemical Analyses
Type: Journal Article | Journal: Current microbiology | Year: 2016

The decomposition of penicillin G and erythromycin antibiotics at concentration of 0.2mgml(-1) by gamma irradiation at 50kGy followed by biological treatment with Cupriavidus metallidurans CH34 was evaluated. Degradation of penicillin G and erythromycin was analyzed using nuclear magnetic resonance analysis (NMR), fourier transform infrared spectroscopy (FTIR), and chemical oxygen demand (COD). The exposure to the absorbed dose of 50kGy caused degradation of penicillin G and erythromycin in the aqueous solution. The complete disappearance of NMR and FTIR peaks following irradiation confirmed the breakage of the -lactam ring in penicillin G, and the decarboxylation and cleavage of the thiazolidine ring and for erythromycin, the complete destruction of the three aromatic rings. Irradiation alone removed 52.8 and 65.5% of penicillin G and erythromycin, respectively. Further reduction to 12.6 and 14% of the original penicillin G and erythromycin COD, respectively, was achieved using treatment of the irradiation products with C.metallidurans.


Touati B.,National Institute of Agronomical Research of Tunisia | Touati B.,Tunisian National Institute of Applied Sciences and Technology | Chograni H.,Tunisian National Institute of Applied Sciences and Technology | Hassen I.,National Institute of Research and Physicochemical Analysis | And 3 more authors.
Chemistry and Biodiversity | Year: 2011

Essential oils of Lavandula dentata, a Tunisian native plant, were isolated from leaves and flowers by hydrodistillation in a Clevenger-type apparatus and characterized by GC-FID and GC/MS analyses. The average essential oil yields, means of five replicates, were higher for the flowers (8.60 mg/g) than for the leaves (6.56 mg/g). A total of 72 compounds were identified, accounting for 98.1 and 97.7% of the total oil composition of the leaves and flowers, respectively. The main essential oil constituents were 1,8-cineole, camphor, and L-fenchone, accounting for 33.54, 18.89, and 8.36% in the leaf oils and for 19.85, 23.33, and 7.13% in the flower oils, respectively. Besides this quantitative variation, the results also showed considerable qualitative variation between the essential oils of the two plant parts analyzed. These differences might be adaptative responses to ecological exigencies. Copyright © 2011 Verlag Helvetica Chimica Acta AG, Zürich.


Limam I.,IRSTEA | Limam I.,University of Carthage | Limam I.,National Institute of Research and Physicochemical Analysis | Limam R.D.,IRSTEA | And 7 more authors.
Ecotoxicology and Environmental Safety | Year: 2016

In this study isotopic tracing using 13C labelled pentachlorophenol (PCP) and 2,4,6-trichlorophenol (2,4,6-TCP) is proposed as a tool to distinguish the loss of PCP and 2,4,6-TCP due to biodegradation from other physical processes. This isotopic approach was applied to accurately assess in situ PCP and 2,4,6-TCP degradation under methanogenic conditions in several microcosms made up of household waste. These microcosms were incubated in anaerobic conditions at 35 °C (mesophilic) and 55 °C (thermophilic) without agitation. The volume of biogas produced (CH4 and CO2), was followed for a period of 130 days. At this stage of stable methanogenesis, 13C6-PCP and 13C6-2,4,6-TCP were introduced anaerobically in microcosms and its monitoring at mesophilic and thermophilic conditions was performed in parallel by gas chromatography mass spectrometry (GC-MS) and gas chromatography isotope-ratio mass spectrometry (GC-IRMS). This study proved the almost total dechlorination of bioavailable PCP and 2,4,6-TCP into 4-CP at 35 °C. Nevertheless, high rate adsorption in particular materials of the two compounds was observed. Furthermore, Carbon-13 Nuclear Magnetic Resonance (13C-NMR) Spectroscopy analysis of 13C labelled 2,4,6-TCP mesophilic incubations showed the partial mineralization of 4-CP at 35 °C to acetate and then to HCO3-. Consequently, NMR results confirm the biogas isotopic results indicating the mineralization of 13C labelled 2,4,6-TCP into 13C (CH4 and CO2). Concerning 13C labelled PCP mesophilic incubations, the isotopic composition of the biogas still natural until the day 262. In contrast, no dechlorination was observed at 55 °C. Thus PCP and 2,4,6-TCP were persistent in thermophilic conditions. © 2016 Elsevier Inc.


Limam I.,IRSTEA | Limam I.,University of science of Bizerte | Limam I.,National Institute of Research and Physicochemical Analysis | Mezni M.,National Institute of Research and Physicochemical Analysis | And 5 more authors.
Chemosphere | Year: 2013

In this paper, the isotopic tracing using 13C-labeled phenol and bisphenol A was used to study their biodegradation during anaerobic digestion of municipal solid waste. Microcosms were incubated anaerobically at 35°C (mesophilic conditions) and 55°C (thermophilic conditions) without steering. A continuous follow-up of the production of biogas (CH4 and CO2), was carried out during 130d until the establishment of stable methanogenesis. Then 13C12-BPA, and 13C6-phenol were injected in microcosms and the follow-up of their degradation was performed simultaneously by gas chromatography isotope-ratio mass spectrometry (GC-IRMS) and gas chromatography mass spectrometry (GC-MS). Moreover, Carbon-13 Nuclear Magnetic Resonance (13C-NMR) Spectroscopy is used in the identification of metabolites. This study proves that the mineralization of phenol to CO2 and CH4 occurs during anaerobic digestion both in mesophilic and thermophilic conditions with similar kinetics. In mesophilic condition phenol degradation occurs through the benzoic acid pathway. In thermophilic condition it was not possible to identify the complete metabolic pathway as only acetate was identified as metabolite. Our results suggest that mineralization of phenol under thermophilic condition is instantaneous explaining why metabolites are not observed as they do not accumulate. No biodegradation of BPA was observed. © 2012 Elsevier Ltd.


Limam I.,National Institute of Research and Physicochemical Analysis | Limam I.,University of science of Bizerte | Driss M.R.,University of science of Bizerte
International Journal of Environmental Science and Technology | Year: 2013

An off-line solid-phase extraction procedure followed by high-performance liquid chromatography with ultraviolet detection for the determination of 16 priority polycyclic aromatic hydrocarbon pollutants in aqueous matrices was described. Diverse aspects determining extraction efficiency such as packing type (disk or cartridge), elution solvents and addition of organic modifiers to the sample were evaluated. Elution with acetonitrile yields the highest recoveries. Rinsing the sample bottle with acetonitrile and combining the rinse with the sample extract avoids the adsorption of polycyclic aromatic hydrocarbons on the walls of the water containers. The use of isopropanol or methanol 10 % (V/V) was the most appropriate amount for the enrichment of 2- to 6-ring aromatic compounds only on C18 cartridge. The recoveries for all studied polycyclic aromatic hydrocarbons are ranged from 71.4 to 95.2 % for a treated water samples of 500 mL. The proposed method gives very low detection limits (subnanograms per liter) and it has been applied to drinking water, surface water and industrial effluent (oil refinery) samples with good results. © 2013 Islamic Azad University (IAU).


PubMed | IRSTEA, University of Carthage and National Institute of Research and Physicochemical Analysis
Type: | Journal: Ecotoxicology and environmental safety | Year: 2016

In this study isotopic tracing using (13)C labelled pentachlorophenol (PCP) and 2,4,6-trichlorophenol (2,4,6-TCP) is proposed as a tool to distinguish the loss of PCP and 2,4,6-TCP due to biodegradation from other physical processes. This isotopic approach was applied to accurately assess in situ PCP and 2,4,6-TCP degradation under methanogenic conditions in several microcosms made up of household waste. These microcosms were incubated in anaerobic conditions at 35C (mesophilic) and 55C (thermophilic) without agitation. The volume of biogas produced (CH4 and CO2), was followed for a period of 130 days. At this stage of stable methanogenesis, (13)C6-PCP and (13)C6-2,4,6-TCP were introduced anaerobically in microcosms and its monitoring at mesophilic and thermophilic conditions was performed in parallel by gas chromatography mass spectrometry (GC-MS) and gas chromatography isotope-ratio mass spectrometry (GC-IRMS). This study proved the almost total dechlorination of bioavailable PCP and 2,4,6-TCP into 4-CP at 35C. Nevertheless, high rate adsorption in particular materials of the two compounds was observed. Furthermore, Carbon-13 Nuclear Magnetic Resonance ((13)C-NMR) Spectroscopy analysis of (13)C labelled 2,4,6-TCP mesophilic incubations showed the partial mineralization of 4-CP at 35C to acetate and then to HCO(3-). Consequently, NMR results confirm the biogas isotopic results indicating the mineralization of (13)C labelled 2,4,6-TCP into (13)C (CH4 and CO2). Concerning (13)C labelled PCP mesophilic incubations, the isotopic composition of the biogas still natural until the day 262. In contrast, no dechlorination was observed at 55C. Thus PCP and 2,4,6-TCP were persistent in thermophilic conditions.

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