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1.
Kherroubi Seddik Benkahla Youb Khaled Labsi Nabila Ragui Karim Bensaci Abdelghani Boutra Abdelkader Ouyahia Seif-Eddine Benzema Mahdi 《Journal of Thermal Analysis and Calorimetry》2021,144(3):623-646
Journal of Thermal Analysis and Calorimetry - Through this paper, three-dimensional fluid flow and heat transfer of Al2O3 nanofluid within ventilated enclosures was taken into consideration.... 相似文献
2.
We use the Schaefer fixed-point theorem, combined with the Bressan-Colombo selection theorem for lower-semicontinuous multivalued
operators with nonempty closed and decomposable values, for the investigation of the existence of solutions for first-and
second-order impulsive functional differential inclusions with variable times.
Published in Neliniini Kolyvannya, Vol. 10, No. 4, pp. 443–463, October–December, 2007. 相似文献
3.
S. Bouguessa A.K. Gouasmia S. Golhen L. Ouahab J.M. Fabre 《Tetrahedron letters》2003,44(52):9275-9278
New TTF precursors for the construction of conducting and magnetic materials have been synthesized by using the palladium-catalyzed cross-coupling reaction between a mono- or a bis(trialkylstannyl)tetrathiafulvalene and a series of heteroaryl halides. The redox potential and some crystallographic data of these new building blocks are presented and discussed. 相似文献
4.
5.
Fettouhi M Ouahab L Boukhari A Cador O Mathonière C Kahn O 《Inorganic chemistry》1996,35(17):4932-4937
The goal of this work was to synthesize new molecular bricks which could be used as precursors of heterobimetallic low-dimensional compounds. Along this line, four compounds have been synthesized and structurally characterized, namely (NBu(4))(2)[Ni(Cl(2)opba)] (1), (NBu(4))(2)[Cu(Cl(2)opba)] (2), (NBu(4))(5)[Mn(Cl(2)opba)(DMSO)(2)](4) (3), and Cu(en)(2)[Mn(Cl(2)opba)(H(2)O)(2)](2).2DMSO (4), with Cl(2)opba = (4,5-dichloro-o-phenylene)bis(oxamato), NBu(4) = tetra-n-butylammonium, en = ethylenediamine, and DMSO = dimethyl sulfoxide. Compounds 1 and 2 are isostructural; they crystallize in the monoclinic system, space group C2/c, Z = 4, with a = 18.708(2) ?, b = 17.525(2) ?, c = 14.763(9) ?, and beta = 92.03(4) degrees for 1 and a = 18.928(2) ?, b = 17.634(2) ?, c = 14.704(9) ?, and beta = 92.38(3) degrees for 2. 3 crystallizes in the tetragonal system, space group P&fourmacr;2(1)c, Z = 2, with a = 26.295(10) ? and c = 12.342(7) ?. The structure shows a random occupation of the metal site by Mn(III) and Mn(II) ions in 3/4 and 1/4 ratios, respectively. 4 crystallizes in the triclinic system, space group P&onemacr;, Z = 1, with a = 7.066(7) ?, b = 11.844(1) ?, c = 14.292(5) ?, alpha = 105.64(2) degrees, beta = 97.67(5) degrees, and gamma = 102.13(3) degrees. The structure consists of Mn(III)Cu(II)Mn(III) trinuclear species, with Cu-O-Mn bridges involving oxygen atoms of the oxamato groups already linked to the metal atom. The magnetic properties of compounds 1-4 have been investigated and quantitatively interpreted. For 3, this magnetic investigation has been performed on a single crystal, which allows us to determine unambiguously the sign of the axial zero-field splitting parameter for the Mn(III) ion. The potentialities of these new molecular bricks have been discussed. 相似文献
6.
The purpose of this Note is the study of the structure and fluxional behavior of the complex [{Ru(CO)2(η5C5H5)}3(η1:η1:η2:-CC)]+, using density functional methods. The molecular geometry of this complex will be optimized, the transition state (TS) of the fluxional process will be determined and the origin of the energy barrier will be analyzed. 相似文献
7.
The Near Surface Mounted (NSM) technique has been used in recent years for the strengthening of reinforced concrete beams. It involves the insertion of strips or rods of polymers reinforced with carbon fiber (CFRP) in the groove made previously in the concrete cover of corresponding surfaces, filled with epoxy adhesive for fixation. In order to characterize the bond behavior of the laminate and rods to concrete, an experimental work of pullout-bending tests was carried out. The pullout force at the laminate and the slip at the free and loaded end were measured. The influences of the concrete strength, the strength of the bond, and bond length on the bonding behavior between the three materials concrete, epoxy adhesive and CFRP were analyzed. 相似文献
8.
9.
Lahcène Ouahab Stéphane Golhen Yukihiro Yoshida Gunzi Saito 《Journal of Cluster Science》2003,14(3):193-204
The synthesis, structural and magnetic characterizations of a new charge transfer salt (BEDT-TTF)4[Cr(OH)6Mo6O18]2H2O based on the planar paramagnetic Anderson–Evans polyoxometalate are reported. Structural parameters: T=293 K, triclinic (P
), a=5.9545(2) Å, b=16.3767(6) Å, c=21.8643(6) Å, =110.829(2)°, =91.262(2)°, =98.129(1)°, Z=1, R=0.0540. The crystal structure is characterized by a face-to-face stacking of the anions giving rise to a one-dimensional inorganic chain which develops along the a direction. The organic layers contain two crystallographically independent BEDT-TTF dimers that form alternating stacks along the b direction. This organic chain is perpendicular to the inorganic chains. The charges on BEDT-TTF dimers are deduced to +1.2(1) and +1.7(1) on the basis of the intramolecular bond lengths. The EPR spectrum at 2.5 K is characterized by the superposition of BEDT-TTF+ and [CrIII(OH)6Mo6O18]3– signals. The static susceptibility can be fitted by the Curie–Weiss law down to 1.9 K and the magnetic moment at 300 K is estimated to 4.21
B
, suggesting the uncorrelated spin system with BEDT-TTF+ (S=1/2) and CrIII (S=3/2) ions. This interpretion is consistent with the charge disproportionation on BEDT-TTF dimers along the stack, which is supported by the refined molecular structure and is closely related to the insulating behavior (<10–9Scm–1 at RT). 相似文献
10.
A Calculation of the Culler-shalen Seminorms Associated to Small Seifert Dehn Fillings 总被引:1,自引:0,他引:1
We determine the relationship between the multiplicities ofthe zeros of certain rational functions defined on the SL2(C)and PSL2C character varieties of knot exteriors. This leadsto a formula for the CullerShalen seminorms associatedto small Seifert Dehn fillings of such manifolds. 2000 MathematicsSubject Classification: 57M05, 57M27, 57R65. 相似文献