排序方式: 共有22条查询结果,搜索用时 15 毫秒
1.
DEBACHE Abdelmadjid BOULCINA Raouf TAFER Radia BELFAITAH Ali RHOUATI Salah CARBONI Bertrand 《中国化学》2008,26(11):2112-2116
The synthesis of 1,2,3,4-dihydropyrimidinone/thione derivatives was achieved in good to excellent yields using calcium(II) nitrate as catalyst to promote the Biginelli three-component condensation reaction from a diversity of aromatic aldehydes, β-keto compounds and urea or thiourea. The reaction was carried out under solvent-free conditions. 相似文献
2.
Abdelmadjid Recioui 《Journal of Optimization Theory and Applications》2012,153(2):497-512
The design of nonuniformly spaced linear array antennas using Particle Swarm Optimization method is considered. The purpose is to match a desired radiation pattern and improve the performance of these arrays in terms of sidelobe level. This performance criterion determines how well the system is suitable for wireless communication applications and interference reduction. Two approaches are considered: in the first, the design of element placement with the constraint of array length being imposed is performed. The second is based on element position perturbation starting from a uniform element distribution. Many examples are treated to show the effectiveness of the designs and the effect some other parameters might have on the overall performance of the array. 相似文献
3.
A variety of novel 2-alkylthiopyrimidines were synthesized through simple condensation of arylidenemalononitriles with different 2-alkylthiouronium halide derivatives catalyzed by anhydrous potassium carbonate (K2CO3). The reactions have been carried out under mild conditions in i-PrOH, and the products were obtained in moderate to good yields with a simple work-up method. Subsequently, some examples of these compounds have been converted into Tacrine analogs by applying the Friedländer reaction. 相似文献
4.
Rima Laroum Fabienne Berrée Thierry Roisnel Vincent Dorcet Bertrand Carboni Abdelmadjid Debache 《Tetrahedron letters》2019,60(35):150988
The AlCl3-promoted reactions of cycloalkanones with hydrazones are described. This approach represents a mild and operationally simple method to access 2,3-diaryl-4,5,6,7-tetrahydro-1H-indazoles and their analogues in good to moderate yields. 相似文献
5.
We report herein the use of triphenylphosphine (TPP) as a new catalyst for the one-pot Biginelli reaction coupling of β-ketoesters, aldehydes and urea (or thiourea) to afford the corresponding dihydropyrimidinones/thiones. 相似文献
6.
Sara Nemouchi Raouf Boulcina Bertrand Carboni Abdelmadjid Debache 《Comptes Rendus Chimie》2012,15(5):394-397
Phenylboronic acid, a non-toxic compound, is used as catalyst for an efficient, rapid, and one-pot three-component synthesis of tetrahydrobenzo[b]pyrans in good to excellent yields. This new procedure has the advantages of operational simplicity, shorter reaction time, higher yields and minimum pollution of the environment. 相似文献
7.
The synthesis of various 1,4‐dihydropyridine and polyhydroquinoline derivatives was achieved in good to excellent yields using cadmium (II) nitrate as catalyst to promote the classical and modified Hantzsch conditions in good yields under mild conditions. 相似文献
8.
A facile and efficient synthesis of new 1,4‐dihydropyridine derivatives was reported via Hantzsch three‐component condensation reaction of aldehydes or formylphenylboronic acids, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of triethylamine under solvent‐free conditions. The method described here offers several advantages including high yields, short reaction times, and simple work‐up procedure. 相似文献
9.
Fahima Arab F. Ali Sahraoui Abdelmadjid Bouhemadou Layachi Louail 《Phase Transitions》2016,89(5):480-513
Structural stability and mechanical and thermodynamic properties of the orthorhombic and trigonal MgSiN2 polymorphs (or-MgSiN2 and tr-MgSiN2) were investigated through density functional theory and quasi-harmonic Debye model (QHDM). Our calculations show that or-MgSiN2 is energetically the stable polymorph at low pressure, in agreement with previous experimental and theoretical study. Under pressure, a crystallographic transition from the orthorhombic structure to the trigonal one occurs around 25, 17.45 and 19.05 GPa as obtained from the generalized gradient approximation of Perdew-Wang (GGA-PW91), the generalized gradient approximation parameterized recently by Perdew et al (GGA-PBEsol) and the local density approximation developed by Ceperley and Alder and parameterized by Perdew and Zunger (LDA-CAPZ), respectively. Single-crystalline and polycrystalline elastic constants and related properties, namely Vickers hardness, acoustic Grüneisen parameter, minimum thermal conductivity, isotropic sound velocities and Debye temperature, were numerically estimated for both or-MgSiN2 and tr-MgSiN2. We have showed that the hardness of tr-MgSiN2 is comparable to that of the harder materials like c-BN and B6O. Temperature and pressure dependencies of volume, bulk modulus, thermal expansion, Grüneisen parameter, heat capacities and Debye temperature were investigated using QHDM. 相似文献