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31.
In this paper, we introduce and study new concepts of almost L-weakly and almost M-weakly compact operators. 相似文献
32.
M. Chrif 《Applicable analysis》2013,92(7):865-871
33.
We know that, in general, an algebra satisfying an Engel's condition is a nilalgebra. But an Engel's condition don't implies necessarily the nilpotency of the algebra. In this paper we show that every Bernstein algebra satisfying the second or the third Engel's condition is genetic, that is, the kernel of his weight fonction is nilpotent. This is also the case for a Bernstein algebra satisfying the second weak Engel's condition. On sait que, en général, toute algèbre vérifiant une condition d'Engel est une nilalgèbre. Cependant, une condition d'Engel n'entraîne pas nécessairement la nilpotence de l'algèbre. Nous montrons, dans ce papier, que taute algèbre de Bernstein vérifiant la deuxième ou la troisième condition d'Engel est génétique, c'est-à-dire, le noyau de sa pondération est nilpotent. C'est aussi le cas pour la deuxième condition faible d'Engel. 相似文献
34.
Clément Ghiazza Moussa Ndiaye Anfal Hamdi Anis Tlili Thierry Billard 《Tetrahedron》2018,74(45):6521-6526
Herein, the direct C-5 fluoroalkylselenolation of 8-aminoquinolines is described. The Pd-catalyzed reaction is performed with the in situ generated fluoroalkylselenyl chloride and various 8-aminoquinoline amides or sulfonamides. The desired products were formed in moderate to excellent yields. 相似文献
35.
Self-assembly of coordination frameworks exhibiting original architectures is an active area of research. Generally, such assemblies are constructed from organic spacers and transition metals of different geometrical structures. Herein, we report a novel class of supramolecular coordination assemblies with organometallic linkers based on metalated quinonoid and thioquinonoid complexes that serve as spacers. The organometallic ligands are stable and have the general formula [Cp*M(eta(4)-benzoquinone)] (o- and p-benzoquinone, Cp*=C(5)Me(5), M=Rh, Ir) and [Cp*Ir(eta(4)-thiobenzoquinone)] (o- and p-thiobenzoquinone). These units bind through both oxygen or sulfur atoms to metal ions of different coordination geometry, such as Cu(I), Ag(I), and Pt(II), to generate supramolecular coordination networks, with the metalated quinonoid or thioquinonoid linkers acting as backbones and the metal centers as nodes. This novel family of supramolecular assemblies exhibits short pi-pi and MM interactions. These results illustrate successfully the role of the organometallic linkers to produce an impressive range of novel supramolecular architectures that hold promise for the development of functional materials. 相似文献
36.
A. Moussa 《Journal of Evolution Equations》2016,16(1):65-93
This paper explores two generalizations of the classical Aubin–Lions Lemma. First, we give a sufficient condition to commute weak limit and multiplication of two functions. We deduce from this criteria a compactness theorem for degenerate parabolic equations. Second, we state and prove a compactness theorem for noncylindrical domains, including the case of dual estimates involving only divergence-free test functions. 相似文献
37.
H. Ben Naceur I. Moussa O. Tottereau A. Rebey B. El Jani 《Physica E: Low-dimensional Systems and Nanostructures》2009,41(10):1779-1783
Thin InAs epilayers were grown on GaAs(1 0 0) substrates exactly oriented and misoriented toward [1 1 1]A direction by atmospheric pressure metalorganic vapor phase epitaxy. InAs growth was monitored by in situ spectral reflectivity. Structural quality of InAs layers were studied by using high-resolution X-ray diffraction. No crystallographic tilting of the layers with respect to any kind of these substrates was found for all thicknesses. This result is discussed in terms of In-rich growth environment. InAs layers grown on 2° misoriented substrate provide an improved crystalline quality. Surface roughness of InAs layers depend on layer thickness and substrate misorientation. 相似文献
38.
Moussa Mbaye Mame Diabou Gaye Seye Atanasse Coly Alphonse Tine Jean-Jacques Aaron 《Analytical and bioanalytical chemistry》2009,394(4):1089-1098
The photochemically induced fluorescence (PIF) spectral properties of α-cypermethrin in organic solvents (hexane, dichloromethane,
acetonitrile, ethanol) and in cyclodextrin aqueous solutions (β-CD and 2-hydroxypropyl-β-CD, 2-HP-β-CD) were investigated.
The photolysis kinetics of α-cypermethrin were evaluated in the various media. The PIF signal was found to be significantly
enhanced in the CD media relative to the organic solvents. The stoichiometry and the formation constants of the α-cypermethrin
inclusion complexes formed with the CDs were determined. The analytical performances of the PIF method were improved in the
presence of HP-β-CD relative to the other media, and a CD-enhanced PIF analytical method was developed. The limits of detection
and limits of quantification ranged, respectively, between 6 and 98 ng/mL and between 24 and 343 ng/mL, depending on the medium.
Application to the analysis of tap water and Senegal natural water samples collected close to agricultural areas and spiked
with α-cypermethrin yielded satisfactory recoveries going from about 77% to 98%. An interference study of foreign species,
including pesticides and inorganic ions likely to be present in natural waters, was also carried out.
Figure Photolysis reaction of α-cypermethrin in presence of HP-β-CD 相似文献
39.
Shichao Yue Walied A. Moussa L. Richard Williston 《Applied Physics A: Materials Science & Processing》2014,115(2):409-414
The plasmon resonance of periodic and random arrays of Au-nanodiscs and nano-squares was investigated experimentally and numerically. By randomization, plasmon resonance spectra become broadened, however, the electro-magnetic field enhancement is augmented by a factor of 10–10 $^2$ times at some specific wavelength as shown by the finite-element time-domain calculations. The spatial localization takes place at a fewer hot-spots. The randomized structures are promising for the applications in opto-electronics, sensing and light harvesting. 相似文献
40.