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1.
Amel Souibgui Anne Gaucher Jérôme Marrot Flavien Bourdreux Faouzi Aloui Béchir Ben Hassine Damien Prim 《Tetrahedron》2014
New series of acridines and phenanthrolines have been prepared from β-chlorovinyl aldehydes and various aniline derivatives allowing the installation of valuable substituents, such as ketone, nitro or amino groups at the heterocyclic core. X-ray analyses confirmed the structures of acridines and phenanthrolines as well as the presence of partially hydrogenated rings and their crucial impact on the overall shape of the acridine-based architectures. 1H NMR revealed the helical behaviour of several acridine motives. Comparison of UV data between architectures and influence of number of partially hydrogenated rings is also described. 相似文献
2.
Harech Mohamed Amine Dabbebi Rawia Abouliatim Younes Elhafiane Youssef Smith Agnès Mesnaoui Mohamed Niboue Lahbib Baklouti Samir 《Journal of Thermal Analysis and Calorimetry》2022,147(10):5677-5686
Journal of Thermal Analysis and Calorimetry - The aim of the present work is to characterize the phosphate sludge from two different countries: Morocco and Tunisia, and to study the difference... 相似文献
3.
Let 1<p?2 and q be such that . It is well known that the norm of the Lp-Fourier transform of the additive group is , where . For a nilpotent Lie group G, we obtain the estimate , where m is the maximal dimension of the coadjoint orbits. Such a result was known only for some particular cases. 相似文献
4.
Salma Azaouzi Ali Baklouti Mounir Elloumi 《Annali di Matematica Pura ed Applicata》2014,193(3):723-737
Let \(K\) be a compact subgroup of automorphisms of \(\mathbb R ^n\) . We prove in this paper a generalization of Hardy’s uncertainty principle on the semi-direct product \(K\ltimes \mathbb R ^n\) , and we solve the sharpness problem. As a consequence, a complete analogue of classical Hardy’s theorem is obtained. The representation theory and the Plancherel formula play an important role in the proofs. 相似文献
5.
Abdelhak Fahsi Mohamed Belhaq Faouzi Lakrad 《Communications in Nonlinear Science & Numerical Simulation》2009,14(4):1609-1616
This paper examines the suppression of hysteresis in a forced nonlinear self-sustained oscillator near the fundamental resonance. The suppression is studied by applying a rapid forcing on the oscillator. Analytical treatment based on perturbation analysis is performed to capture the entrainment zone, the quasiperiodic modulation domain and the hysteresis area as well. The analysis leads to a strategy for the suppression of hysteresis occurring between 1:1 frequency-locked motion and quasiperiodic response. This hysteresis suppression causes the disappearance of nonlinear effects leading to a smooth transition between the quasiperiodic and the frequency-locked responses. Specifically, it appears that a rapid forcing introduces additional apparent nonlinear stiffness which can effectively suppress hysteresis in a certain range of the rapid excitation frequency. This work was motivated by the important issue of controlling and eliminating hysteresis often undesirable in mechanical systems, in general, and in application to microscale devices, especially. 相似文献
6.
7.
Ayari Faouzi Mannei Emna Asedegbega-Nieto Esther Mhamdi Mourad Guerrero-Ruiz Antonio Ricardo Delahay Gérard Ghorbel Abdelhamid 《Journal of Thermal Analysis and Calorimetry》2018,131(2):1295-1306
Journal of Thermal Analysis and Calorimetry - Thermal decomposition (2 K min?1) of ammonium heptamolybdate tetrahydrate, performed between room temperature and... 相似文献
8.
Mabrouk Khelifi Imen Mkaouar Faouzi Hlel Abdelhamid Ben Salah Ridha Zouari 《Ionics》2010,16(8):709-715
The crystal structure of (C5N2H7)4.HBi2Cl11 has been determined at room temperature by single crystal X-ray diffraction. The compound crystallizes in the triclinic system with Pī space group. The crystal structure consists of two asymmetric inequivalent molecules of 4-aminopyridinium and anionic HBi2Cl11 chains. The HBi2Cl11 anionic chains stacked along the a-axis are formed with Bi2Cl11 dimers connected to each other via hydrogen atoms. The crystal packing is stabilized with N–H...Cl hydrogen bonds connecting aminopyridinium units to the HBi2Cl11 anionic chains. The title compound exhibits an order–disorder phase transition at 338 K. The AC electrical conductivity properties of (C5N2H7)4.HBi2Cl11 compound have been investigated by means of impedance spectroscopy measurements over wide ranges of frequencies and temperatures, 200 Hz to 5 MHz and 303 to 418 K, respectively. Detailed analysis of the impedance spectrum suggests that the electrical properties of the material are strongly temperature dependent. The frequency-dependent conductivity data were fitted in the Jonscher's law: $ \sigma \left( \omega \right) = \sigma (0) + A{\omega^n} $ . The nature of variation of DC conductivity suggests Arrhenius type of electrical conductivity. 相似文献
9.
Hamadi Jerbi Thouraya Kharrat Faouzi Omri 《Mediterranean Journal of Mathematics》2016,13(5):2507-2524
In this paper, we consider a class of bilinear systems in dimension three which can be an extension of another one in \({\mathbbm{R}^{2}}\). We prove that there exists some homogeneous feedback of degree zero stabilizing the considered class if and only if these feedbacks are constants. 相似文献
10.
Nabil Smichi Ahmed Fendri Raja Chaabouni Faouzi Ben Rebah Youssef Gargouri Nabil Miled 《Applied biochemistry and biotechnology》2010,162(5):1483-1496
A lipolytic activity was located in the sardine digestive glands (pyloric caeca), from which a sardine digestive lipase (SaDL)
was purified. Pure SaDL has a molecular mass of 43 kDa as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis
analysis. The enzyme was found to be more active on short-chain triacylglycerols than on long-chain ones. SaDL does not present
the interfacial activation phenomenon. Control experiments were performed under the same experimental conditions, with dromedary
and turkey pancreatic lipases and showed a positive interfacial activation phenomenon. Sodium deoxycholate (NaDC) has an inhibitory
effect on the lipase activity. The pure enzyme lost 40% of its activity in presence of 8 mM NaDC. SaDL was found to be mostly
stable at low pH values. Interestingly, no colipase was detected in the sardine pyloric caeca. Analogous results were reported
for the scorpion and the crab digestive systems. This is in line with the idea that colipase might has evolved in mammal animals
simultaneously with the appearance of an exocrine pancreas. No similarity was found between the NH2-terminal amino acid residues of SaDL and those of lipases from the digestive tract of other species. Altogether, these results
suggest that SaDL is a member of a new group of lipases belonging to aquatic species. 相似文献