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1.
Nesrine Koriche Aissa Bouguelia Mohamed Mohammedi Mohamed Trari 《Journal of Materials Science》2007,42(13):4778-4784
A novel oxide AgMnO2 was prepared from LiMnO2 via Ag+ → Li+ exchange in the eutectic melt AgNO3-KNO3. It crystallizes in a monoclinically distorted unit cell (SG C2/m) caused by the Jahn-Teller (J-T) ion Mn3+ (3d
4). The structure was refined by isotypy with the crednerite CuMnO2. There are two long axial Mn–O of 264.2(0) pm and four equatorial bonds of 192.7(3) pm and Mn–O–Mn adjoining (83.07°) are
bent below the ideal angle. The thermal variation of the magnetic susceptibility (χ/T
−1) obeys a Curie-Weiss law with manganese in a trivalent, high spin (HS) state accommodated in elongated MnO6 octahedra (14.8%). Direct coupling between Mn3+ involves negative exchange interactions through long-range antiparallel moments with a temperature θ
p
= −436 K and a magnetic moment of 5.26 μB/Mn3+ slightly larger than the spin only moment. The title oxide is stable in air up to ∼680 °C before it decomposes into metal
silver. It displays a semi-conducting behavior with an activation energy of ∼0.45 eV, characteristic of a conduction by low
mobility polarons between Ag+/2+ where nearly all polarons are bonded. The photoelectrochemical properties of AgMnO2 have been investigated by photocurrent technique in 1 M KOH. The cathodic photocurrent J
ph provides unambiguous evidence of p-type character attributed to oxygen insertion (0.025 oxygen by formula unit) as required by the charge compensating mechanism.
The valence band is made up of Ag−4d wave functions positioned at ∼5.14 eV below vacuum. A comparison with CuMnO2 was also reported. 相似文献
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This research evaluated the effect of drought on total and individual polyphenol contents as well as the antioxidant activities of cumin (Cuminum cyminum L.) seeds of 2 geographic origins, Tunisia (TCS) and India (ICS). Plants were treated with different levels of water deficit: control. Our results indicated that, in both varieties, moderate water deficit (MWD) improved the number of umbels per plant as well as the number of umbellets per umbel and the seed yield, in comparison to the control, but it decreased under severe water deficit (SWD). Besides, total phenolic contents were higher in the treated seeds and drought increased the level of total and individual polyphenols. This increase was appreciably more important in TCS than in ICS. Moreover, antioxidant activities of the extracts were determined by 4 different test systems, namely 2,2-diphenyl-1-picrylhydrazyl, β-carotene/linoleic acid chelating, and reducing power assays, and showed that treated seeds exhibited the highest activity, for both TCS and ICS. 相似文献
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Océane Florès Dr. Denis Velic Nesrine Mabrouk Prof. Ali Bettaïeb Christophe Tomasoni Prof. Jean-Michel Robert Dr. Catherine Paul Dr. Christine Goze Christos Roussakis Dr. Ewen Bodio 《Chembiochem : a European journal of chemical biology》2019,20(17):2255-2261
A family of bi- and tetrametallic gold(I) phosphine dithiocarbamate complexes were synthesized, starting from cyclam and dimethylcyclam polyazamacrocycles, respectively, along with their monometallic gold(I) chloridophosphine precursors. Their antiproliferative properties were evaluated on two cancer cell lines (A549 and NSCLC-N6-L16). Most of the mono- and bimetallic complexes displayed strong activities and, in particular, one bimetallic derivative showed antiproliferative properties in the low micromolar range. Insights into the structure–activity relationships are given, along with determination of the thioredoxin reductase inhibition potential, two-photon imaging of the fluorescent derivatives, and evaluation of gold uptake. 相似文献
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Nesrine Montacer Khadija Dehri Samah Ben Atia Ridha Ben Abdennour 《Asian journal of control》2019,21(1):456-472
This paper concerns the design of robust sliding mode multiobserver for nonlinear systems. A discrete uncoupled multimodel structure is retained for the modeling of nonlinear systems. Unlike the classically used multimodel structures, the retained uncoupled multimodel is known by its flexibility of modeling, thus, the structures of the partial models are adapted to the complexity of the local models in each operating zone. Sufficient conditions are provided, in terms of linear matrix inequalities (LMIs), to ensure the asymptotic stability of the proposed sliding mode multiobserver. A convergence analysis is achieved to obtain the convergence radius. A numerical example and a real time application on a transesterification reactor are carried out to illustrate, once again, the performance of the proposed sliding mode multiobserver in terms of precision and rapidity of convergence. 相似文献
7.
Nesrine Chakchouk Bechir Hamdaoui Mounir Frikha 《Wireless Communications and Mobile Computing》2012,12(2):195-205
Wireless sensor networks (WSNs) typically consist of a large number of battery‐constrained sensors often deployed in harsh environments with little to no human control, thereby necessitating scalable and energy‐efficient techniques. This paper proposes a scalable and energy‐efficient routing scheme, called WCDS‐DCR, suitable for these WSNs. WCDS‐DCR is a fully distributed, data‐centric, routing technique that makes use of an underlying clustering structure induced by the construction of WCDS (Weakly Connected Dominating Set) to prolong network lifetime. It aims at extending network lifetime through the use of data aggregation (based on the elimination of redundant data packets) by some particular nodes. It also utilizes both the energy availability information and the distances (in number of hops) from sensors to the sink in order to make hop‐by‐hop, energy‐aware, routing decisions. Simulation results show that our solution is scalable, and outperforms existing schemes in terms of network lifetime. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Nesrine Bahri Asma Atig Ridha Ben Abdennour Fabrice Druaux Dimitri Lefebvre 《国际自动化与计算杂志》2017,14(6):742-754
In this paper, multimodel and neural emulators are proposed for uncoupled multivariable nonlinear plants with unknown dynamics. The contributions of this paper are to extend the emulators to multivariable non square systems and to propose a systematic method to compute the multimodel synthesis parameters. The effectiveness of the proposed emulators is shown through two simulation examples. The obtained results are very satisfactory, they illustrate the performance of both emulators and show the advantages of the multimodel emulator relatively to the neural one. 相似文献
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Samira Filali Nesrine Darragi-Raies Layth Ben-Trad Agns Piednoir Saw-See Hong Fabrice Pirot Ahmed Landoulsi Agns Girard-Egrot Thierry Granjon Ofelia Maniti Pierre Miossec Ana-Maria Trunfio-Sfarghiu 《International journal of molecular sciences》2022,23(21)
The morphology of fibroblast-like synoviocytes (FLS) issued from the synovial fluid (SF) of patients suffering from osteoarthritis (OA), rheumatoid arthritis (RA), or from healthy subjects (H), as well as the ultrastructure and mechanical properties of the FLS-secreted extracellular vesicles (EV), were analyzed by confocal microscopy, transmission electron microscopy, atomic force microscopy, and tribological tests. EV released under healthy conditions were constituted of several lipid bilayers surrounding a viscous inner core. This “gel-in” vesicular structure ensured high mechanical resistance of single vesicles and good tribological properties of the lubricant. RA, and to a lesser extent OA, synovial vesicles had altered morphology, corresponding to a “gel-out” situation with vesicles surrounded by a viscous gel, poor mechanical resistance, and poor lubricating qualities. When subjected to inflammatory conditions, healthy cells developed phenotypes similar to that of RA samples, which reinforces the importance of inflammatory processes in the loss of lubricating properties of SF. 相似文献
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Maher Chaouachi Mohamed Salem Zellama Nesrine Nabi Ahmed Ben Hafsa Khaled Saïd 《Food Analytical Methods》2014,7(1):224-233
In response to the increasing number of genetically modified (GM) events released on the market, control laboratories explore various strategies to simplify and reduce the number of tests needed to characterise the content in genetically modified organism (GMO) of a given sample. Lastly, multiplexing is considered as one of the possible ways to decrease the time and cost of analysis. Here, we report the development of four duplex polymerase chain reaction (PCR) tests for the identification and the quantification of four maize transformation events from which commercial lines have been authorised in Europe namely, Bt11 and Bt176 (Syngenta, DE, USA), Mon810 MaisGard? (Monsanto, MO, USA) and T25 Liberty Link? (Bayer CropScience, Monheim, Germany). The duplex PCR tests combine a maize-specific PCR test hybridising in the Adh1 locus with an event-specific detection system designed on a junction fragment for each of these four GM maize. Real-time PCR tests, suitable to comply with the European regulation, were designed by using Taqman® chemistry. 相似文献