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181.
El Kharrat S Skander M Dahmani A Laurent P Blancou H 《The Journal of organic chemistry》2005,70(21):8327-8331
2-trifluoromethylquinolines 5 are synthesized in high yields using a perfluoroalkylated gem-iodoacetoxy derivative 3 and arylamines 4. The intermediate of this reaction, 2-trifluoromethyl-1,5-diazapentadiene compound 6, was isolated. The procedures are easy, and yields are in general high. This sequence represents a valuable new synthesis of substituted 2-trifluoromethylquinolines and of 2-trifluoromethyl-diazapentadienes (vinamidine compounds). 相似文献
182.
Mostafa A Abdelkader 《Advances in Applied Mathematics》1983,4(1):39-45
The boundary-value problem ?z″ = (z2 ? t2)z′, ? > 0, z(? 1) = α, z(0) = β, t? [?1, 0], has been shown to have a solution, and moreover, depending on the choice of α and β, multiple solutions to it exist. We consider the more general equation f(z, t)z″ = (zr ? ts)z′ for a particular non-negative function f(z, t), and integrate the equation exactly. Depending on α and β, we find that either there are no solutions, or that only unique solutions exist. The conclusion is that the presence of a continuous locus of singular points, given by zr = ts, does not necessarily produce multiple solutions. 相似文献
183.
H.K. Hall H.A.A. Rasoul M. Gillard M. Abdelkader P. Nogues R.C. Sentman 《Tetrahedron letters》1982,23(6):603-606
Cycloaddition reactions of substituted α,β-unsaturated esters with various electronich olefins lead to 6-alkoxy-3,4-dihydro-2H-pyrans. 相似文献
184.
Abdelkader Intissar 《Complex Analysis and Operator Theory》2016,10(7):1411-1426
In Advances in Mathematical Physics (2011) we showed that the weighted shift \(z^{p}\frac{d^{p+1}}{dz^{p+1}} (p=0, 1, 2,\ldots )\) acting on classical Bargmann space \(\mathbb {B}_{p}\) is chaotic operator. In Journal of Mathematical physics (2014), we constructed an chaotic weighted shift \(\mathbb {M}^{*^{p}}\mathbb {M}^{p+1} (p=0, 1, 2,\ldots )\) on some lattice Fock–Bargmann \(\mathbb {E}_{p}^{\alpha }\) generated by the orthonormal basis \( {e_{m}^{(\alpha ,p)}(z) = e_{m}^{\alpha } ; m=p, p+1,\ldots }\) where \( {e_{m}^{\alpha }(z) = (\frac{2\nu }{\pi })^{1/4}e^{\frac{\nu }{2}z^{2}}e^{-\frac{\pi ^{2}}{\nu }(m +\alpha )^{2} +2i\pi (m +\alpha )z}; m \in \mathbb {N}}\) with \(\nu , \alpha \) are real numbers; \(\nu > 0\), \(\mathbb {M}\) is an weighted shift and \(\mathbb {M^{*}}\) is the adjoint of the \(\mathbb {M}\). In this paper we study the chaoticity of tensor product \(\mathbb {M}^{*^{p}}\mathbb {M}^{p+1}\otimes z^{p}\frac{d^{p}}{dz^{p+1}} (p=0, 1, 2, \ldots )\) acting on \(\mathbb {E}_{p}^{\alpha }\otimes \mathbb {B}_{p}\). 相似文献
185.
Marie-Thérèse Aimar Abdelkader Intissar Jean-Martin Paoli 《Communications in Mathematical Physics》1995,172(3):461-466
In this work, we establish new regularity properties for Gribov's operator:H=A
*
A
+
iA
*(A+A
*)A;(,)2, whereA
* andA are the creation and annihilation operators. Particularly, we prove that for all >0,H
–1 is in the class of Carleman's operatorl
1+. 相似文献
186.
Synthesis and Characterization of the New Lacunar Zincophosphate [C6H10N2][ZnP2O8H2]·0.6H2O 下载免费PDF全文
Nadjet Chouat Emanuelle Ligner Mohamed Sassi Mohammed Abdelkrim Hasnaoui Laure Michelin Ludovic Josien Claire Marichal Abdelkader Bengueddach Joël Patarin Jean‐Louis Paillaud 《无机化学与普通化学杂志》2017,643(22):1793-1800
The new zincophosphate of chemical formula [C6H10N2][ZnP2O8H2] · 0.6H2O was hydrothermally synthesized with p‐phenylenediamine as structure‐directing agent. The title compound crystallizes in the trigonal symmetry (proposed space group P3m1), where inorganic zincophosphate chains form layers due to the half occupancy of the unique crystallographic zinc site. The layers are separated from each other by p‐phenylenediammonium dications with hydrogen bonding scheme involving the ammonium protons that reveals a pillar‐like 3D structure aspect. The compound was characterized by powder X‐ray diffraction, multinuclear solid‐state NMR, scanning electron microscopy, chemical analysis, and thermogravimetric analysis. 相似文献
187.
Fouad Belhora Abdelowahed Hajjaji M'hammed Mazroui Fatima Zahra El Fatnani Abdelkader Rjafallah Daniel Guyomar 《先进技术聚合物》2015,26(6):569-573
Electrostrictive polymers have been investigated as electroactive materials for electromechanical energy harvesting. This kind of material is isotope, i.e. there is no permanent polarization compared with piezoelectric material, so in order to ensure its polarization and scavenging energy, the electrostrictive polymers need necessarily an application of a static field. To avoid this problem, we used the hybridization of electrostrictive polymer with electret. The present work aims an analytical modeling for predicting the power convert when the material was mechanically excited. The study was carried out on polyurethane and terpolymer [P(VDF–TrFE–CFE)] films, either without filler or filled with carbon nanopowder. Experimental measurements of the harvested power showed a good agreement with the theoretical behavior predicted by the proposed model. It was also shown that the incorporation of nanofillers increased the power harvested from 5.22 · 10?2 to 1.498 · 10?1 μW cm?3 and from 6.87 · 10?1 to 1.76 μW cm?3 in polyurethane and in the terpolymer, respectively. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
188.
Hemmat M. Abd-Elhady Mona A. Ashor Abdelkader Hazem Fayez M. Saleh Samy Selim Nihal El Nahhas Shams H. Abdel-Hafez Samy Sayed Enas A. Hassan 《Molecules (Basel, Switzerland)》2022,27(1)
The ability of microorganisms to reduce inorganic metals has launched an exciting eco-friendly approach towards developing green nanotechnology. Thus, the synthesis of metal nanoparticles through a biological approach is an important aspect of current nanotechnology. In this study, Streptomyces aizuneusis ATCC 14921 gave the small particle of silver nanoparticles (AgNPs) a size of 38.45 nm, with 1.342 optical density. AgNPs produced by Streptomyces aizuneusis were characterized by means of UV-VIS spectroscopy and transmission electron microscopy (TEM). The UV-Vis spectrum of the aqueous solution containing silver ion showed a peak between 410 to 430. Moreover, the majority of nanoparticles were found to be a spherical shape with variables between 11 to 42 nm, as seen under TEM. The purity of extracted AgNPs was investigated by energy dispersive X-ray analysis (EDXA), and the identification of the possible biomolecules responsible for the reduction of Ag+ ions by the cell filtrate was carried out by Fourier Transform Infrared spectrum (FTIR). High antimicrobial activities were observed by AgNPs at a low concentration of 0.01 ppm, however, no deleterious effect of AgNPs was observed on the development and occurrence of Drosophila melanogaster phenotype. The highest reduction in the viability of the human lung carcinoma and normal cells was attained at 0.2 AgNPs ppm. 相似文献
189.
Electrochemical degradation of buprofezin insecticide in aqueous solutions by anodic oxidation at boron-doped diamond electrode 总被引:1,自引:0,他引:1
Mohamed Errami Rachid Salghi Mohammed Zougagh Abdelkader Zarrouk El Houcine Bazzi Abdelkhaleq Chakir Hassan Zarrok Belkheir Hammouti Lahcen Bazzi 《Research on Chemical Intermediates》2013,39(2):505-516
Buprofezin (2-tert-butylimino-3-isopropyl-5-phenyl-1,3,5-thiadiazinan-4-one) is identified as a commonly used chemical with satisfactory biological activities against sucking insect pests, but its disposal causes serious environmental problems. This pesticide was treated by an electrolysis system using a boron-doped diamond (BDD) as anode and platinum as cathode. A number of experiments were run on a laboratory scale and the results are presented. The chemical oxygen demand (COD) measurement during the processing permitted the evaluation of the kinetic of organic matter decay and the instantaneous current efficiency. Different operating conditions and factors affecting the treatment process including current density, conductive electrolyte, pH, concentration of buprofezin, and time of electrolysis were studied and optimized. The best obtained conditions for COD removal on the BDD anode to degrade buprofezin solutions (COD0 = 1,200 mg L?1) include operating at 60 mA cm?2 and 25 ± 3 °C. The high efficiency of this technology can be explained in terms of the direct electrooxidation at the BDD surface and the oxidation carried out by hydroxyl radicals (OH?) and other electro-generated oxidants (Cl?, ClO?). 相似文献
190.
Ayoub Abdelkader Mekkaoui Sanaa Jennane Abderrazak Aberkouks Brahim Boualy Ahmad Mehdi Mustapha Ait Ali Larbi El Firdoussi Soufiane El Houssame 《应用有机金属化学》2019,33(10)
We report the preparation of palladium nanoparticles supported on mesoporous natural phosphate (Pd@NP) using a wetness impregnation method. The prepared catalyst was characterized using various techniques. Furthermore, the reduction and preparation of the palladium nanoparticles was followed using UV–visible spectra. Based on the Scherrer equation, the crystallite size of the as‐synthesized palladium nanoparticles was 10.88 nm. The performance of the synthesized catalyst was investigated in the reduction of 4‐nitrophenol as a model substrate to 4‐aminophenol using NaBH4 as a hydrogen source. Moreover, catalytic reduction of various nitroarenes was studied and monitored using UV–visible spectroscopy and gas chromatography. The Pd@NP catalyst showed a high activity for the selected reaction and could be recycled. 相似文献