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261.
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Nabil A. Ibrahim Ahmed A. Nada Ahmed G. Hassabo Basma M. Eid Azza M. Noor El-Deen Nabil Y. Abou-Zeid 《Chemical Papers》2017,71(7):1365-1375
This research aims to investigate the influence of soluble starch; lactose; carboxymethyl cellulose; urea; and polyvinylpyrrolidone on synthesis of zinc oxide nanoparticles (ZnO-NPs). Zinc acetate was used as a precursor under alkaline conditions to produce ZnO-NPs as a low-cost and efficient antimicrobial and UV-blocking agent. Characterization and antimicrobial functional properties of prepared nanoparticles were investigated and reported using FTIR, TGA, XRD, TEM, analysis, as well as antimicrobial assay, respectively. The results revealed that the thermal decomposition profile, size of ZnO-NPs, IR spectra, as well as antimicrobial activity of the prepared ZnO-NPs is governed by the type of capping agents. Crystallinity analysis showed identical patterns in peak intensities and width irrespective of the used capping agents. On the other hand, the obtained results disclosed that using soluble starch as a capping agent results in attaining lower particle size of 3–5 nm and higher antimicrobial efficacy as compared with the other capping agents. 相似文献
263.
Tahar Z. Boulmezaoud Keltoum Kaliche Nabil Kerdid 《Advances in Computational Mathematics》2017,43(6):1469-1489
We use inverted finite element method (IFEM) for computing three-dimensional vector potentials and for solving div-curl systems in the whole space \(\mathbb {R}^{3}\). IFEM is substantially different from the existing approaches since it is a non truncature method which preserves the unboundness of the domain. After developping the method, we analyze its convergence in term of weighted norms. We then give some three-dimensional numerical results which demonstrate the efficiency and the accuracy of the method and confirm its convergence. 相似文献
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Tahar Zamene Boulmezaoud Keltoum Kaliche Nabil Kerdid 《Annali dell'Universita di Ferrara》2017,63(2):249-276
We give a constructive proof of some functional inequalities related to the div and curl operators in bounded and unbounded domains of \({{\mathbb {R}}}^3\). Our new innovation consists in giving explicit constants in several geometric configurations. These inequalities are of a first use in solving div-curl systems and vector potential problems arising in physics. 相似文献
265.
An analytical solution is given for a time-decay Rankine vortex profile due to viscous effects. The vortex filament is assumed
to be isolated, strong, concentrated and having zero-meridional flow (i.e. radial and axial velocities are equal to zero).
Zero-meridional renders the governing equations for an unsteady, incompressible and axisymmetric vortex in a simple form.
Based on the tangential momentum equation, the spatial-temporal distributions of the swirl velocity are given in terms of
Fourier-Bessel series by using separation of variables technique. A general formula is derived by total differentiation of
the swirl velocity with respect to time, depicting the viscous dissipation for Oseen and Taylor-like vortex profiles. This
analysis is validated by comparison with previous experimental data.
The English text was polished by Yunming Chen. 相似文献
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Nabil Hayeemasae Indra Surya Hanafi Ismail 《International Journal of Polymer Analysis and Characterization》2016,21(5):396-407
Biocompatibilizer-based refined, bleached, deodorized palm stearin was successfully used as compatibilizer for natural rubber/recycled ethylene–propylene–diene rubber (NR/R-EPDM) blends. It seems effective in improving the state of cure, tensile properties, as well as the swelling resistance and morphology of the blends, indicating an improvement in compatibility between the NR matrix and R-EPDM rendered by biocompatibilizer. This was clearly verified by the dynamic mechanical properties of the blends. The dynamic responses obtained were clearly corresponding to the swelling result. It proves that the cross-link density plays a major role in the changes of storage modulus and degree of entanglement. 相似文献
270.
Synthesis,Docking, and Evaluation of Antimicrobial Activity of a New Series of Acyclo C‐Nucleosides of 1, 2, 4‐Triazolo[4, 3‐a]quinoxaline Derivatives 下载免费PDF全文
Mohammed Salah Ayoup Hany Emary Ali Ahmed Abdel Moneim El Massry Samir Senior Sherine Nabil Khattab Seham Yassen Hassan Adel Amer 《Journal of heterocyclic chemistry》2016,53(1):153-163
In this study, 18 new 3‐benzylquinoxalinyl hydrazones bearing carbohydrate moiety and their corresponding triazoloquinoxalines were synthesized in order to investigate their possible antibacterial and antifungal activities. Some of these compounds such as 4b , 4c , 7b , 7c , and 7d showed promising antibacterial and antifungal activities and were found to have more potent activity compared with that of standard drugs. From structure–activity relationship point of view, increasing the size of the substitutions at position 6 or 7 on the quinoxaline nucleus decreased the antimicrobial activity, while the presence of the hydroxyl groups at C2 (R) and C3 (S) of sugar moieties enhanced the activity. Further, molecular docking studies of the active compounds were performed on different targets belonging to different microorganisms and showed good scoring with further understanding of the various interactions with the active sites of interesting enzymes compared with the co‐crystallized ligands. 相似文献