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排序方式: 共有158条查询结果,搜索用时 328 毫秒
31.
32.
Jallal Zoubir Chaimae Radaa Nadia Bougdour Abderrahim Idlahcen Widad El Hayaoui Naoual Tajat Wail El Mouhri Iliass Nadif Samir Qourzal Malika Tamimi Ali Assabbane Idriss Bakas 《印度化学会志》2022,99(8):100590
Nitrofurazone is a nitrofuran-family synthetic chemical that has been used to treat bacterial infections since 1993. Silver nanoparticles synthesized by the thermal technique on graphite carbon sheets under optimal conditions were used to develop a highly sensitive electrochemical sensor. The main experimental characteristics are optimized to assure that this sensor functions correctly. Scanning electron microscope, X-ray diffraction, infrared spectroscopy were used to determine the chemical composition and morphology of the prepared pastes. With a maximal reduction peak of La nitrofurazone observed at ?0.57V/Ag-NPs@CPE versus Ag/AgCl, this sensor demonstrated good electrocatalytic activity for the reduction of La nitrofurazone. The influence of phosphate buffer solution pH indicates that the numbers of protons and electrons in the reaction at the surface of our constructed sensor were the same. The LOD and LOQ were calculated to be 1.2 × 10?8 M and 1.3 × 10?7 M, respectively. Using the differential pulse voltammetry technique, the calibration curve was established in the concentration range of 10?4 M to 2 × 10?7 M. Our Ag-NPs@CPE sensors were evaluated in order to detect nitrofurazone in real contaminated samples tap water, commercial milk, and human urine, in particular. The electroanalysis results show a very high recovery rate of more than 96% on average, permitting us to determine that our sensors are functional under optimum working conditions. 相似文献
33.
H. Hamdi R. Abderrahim F. Meganem 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(1):32-36
Formation of inclusion complex between benzidine diammonium dipicrate and β-cyclodextrin with stoichiometry 1:2 (guest–host) has been established by UV, 1H NMR, 13C NMR, IR spectra and powder X-ray diffractometry. 1H NMR studies are used to confirm the inclusion and to provide information on the geometry of dipicrate inside the cavity of β-cyclodextrin. 相似文献
34.
Eva Castillejos Dr. Pierre‐Jean Debouttière Dr. Lucian Roiban Abderrahim Solhy Dr. Victor Martinez Dr. Yolande Kihn Dr. Ovidiu Ersen Dr. Karine Philippot Dr. Bruno Chaudret Dr. Philippe Serp Dr. 《Angewandte Chemie (International ed. in English)》2009,48(14):2529-2533
Are you in? Bimetallic PtRu nanoparticles have been selectively confined inside or deposited outside carbon nanotubes (see picture). The confined nanoparticles display significantly higher selectivity and catalytic activity in hydrogenation reactions.
35.
Matrab T Yassar A Viau G Chakroune N Fievet F Lacaze PC 《Journal of colloid and interface science》2006,296(1):95-101
Monodisperse ruthenium nanoparticles functionalized by electroactive oligothiophenes have been prepared and characterized. Using TEM, UV-visible and FTIR we established that the organization of these nanoparticles into nanospheres can be directly controlled via modulation of the pi-pi interaction between the organic components adsorbed on the surface. This finding also shows that the self-assembled nanoheterostructures may be switched from monodisperse nanoparticles to ordered nanospheres by tuning the pH. 相似文献
36.
We give a full characterization of nonsmooth Lyapunov pairs for perturbed sweeping processes under very general hypotheses. As a consequence, we provide an existence result and a criterion for weak invariance for perturbed sweeping processes. Moreover, we characterize Lyapunov pairs for gradient complementarity dynamical systems. 相似文献
37.
38.
Structures of protonated alane-Lewis base donor-acceptor complexes H2X2AlNHn(CH3)(3-n)+ (X = F, Cl, and Br; n = 0-3) as well as their neutral parents were investigated. All the monocations H2X2AlNHn(CH3)(3-n)+ are Al-H protonated involving hypercoordinated alane with a three-center two-electron bond and adopt the C(s) symmetry arrangement. The energetic results show that the protonated alane-Lewis complexes are more stable than the neutral ones. They also show that this stability decreases on descending in the corresponding periodic table column from fluorine to bromine atoms. The calculated protonation energies of HX2AlNHn(CH3)(3-n) to form H2X2AlNHn(CH3)(3-n)+ were found to be highly exothermic. The possible dissociation of the cations H2X2AlNHn(CH3)(3-n)+ into X2AlNHn(CH3)(3-n)+ and molecular H2 is calculated to be endothermic. 相似文献
39.
Abderrahim Chafik 《International Journal of Theoretical Physics》2007,46(10):2488-2493
Brane inflation can provide a promising framework for solving the fine-tuning problem in standard inflationary models. The
aim of this paper is to illustrate the mechanism by which this can be achieved. By considering the supersymmetric two-stage
inflation model we show that the initial fine-tuning of the coupling parameter can be controlled through a relation between
the coupling parameter and the brane tension. 相似文献
40.
Bouzide A 《Organic letters》2002,4(8):1347-1350
Palladium on carbon combined with magnesium bromide catalyzed hydrogenation of Baylis-Hillman olefins to afford the corresponding aldol derivatives in a highly syn-diastereoselective manner is described. [reaction: see text] 相似文献