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61.
Abdallah Assi 《Journal of Pure and Applied Algebra》2010,214(9):1623-1632
This paper has two objectives: we first generalize the theory of Abhyankar-Moh to quasi-ordinary polynomials, then we use the notion of approximate roots and that of generalized Newton polygons in order to prove the embedding conjecture for this class of polynomials. This conjecture-made by S.S. Abhyankar and A. Sathaye-says that if a hypersurface of the affine space is isomorphic to a coordinate, then it is equivalent to it. 相似文献
62.
63.
Chacha and Bensayah [Asymptotic modeling of a Coulomb frictional Signorini problem for the von Kármán plates, C. R. Mécanique 336 (2008), pp. 846–850] have studied the asymptotic modelling of Coulomb frictional unilateral contact problem between an elastic nonlinear von Kármán plate and a rigid obstacle. The main result obtained is that the leading term of the asymptotic expansion is characterized by a two-dimensional Signorini problem but without friction. In this article, we extend this study to the case of a shallow shell under generalized Marguerre-von Kármán conditions. 相似文献
64.
A general class of nonconforming meshes has been recently studied for stationary anisotropic heterogeneous diffusion problems, see Eymard et al. (IMA J. Numer. Anal. 30 (2010), 1009–1043). Thanks to the basic ideas developed in the stated reference for stationary problems, we derive a new discretization scheme in order to approximate the nonstationary heat problem. The unknowns of this scheme are the values at the centre of the control volumes, at some internal interfaces, and at the mesh points of the time discretization. We derive error estimates in discrete norms L ∞(0, T;H 0 1 (Ω)) and W 1,∞(0, T;L 2(Ω)), and an error estimate for an approximation of the gradient, in a general framework in which the discrete bilinear form involved in the finite volume scheme satisfies some ellipticity condition. 相似文献
65.
Jeramy Dickerson Konstantinos Pantzas Tarik Moudakir Abdallah Ougazzaden Paul L. Voss 《Optical and Quantum Electronics》2013,45(7):681-686
We report the numerical study of n-GaN/i-InGaN/p-GaN solar cells on Ga-face substrates with thin GaN interlayers present in the intrinsic InGaN region. These interlayers have recently been shown to significantly increase the crystal quality of thick InGaN layers $(>\!\!\!120\,\text{ nm})$ . We find that tunneling is efficient in n-i-p structures having interlayers $\le \! 1.5\,\text{ nm}$ thick if polarization charges are sufficiently screened. If left unscreened, the large polarization charges naturally formed at the heterointerfaces degrades n-i-p performance, at a given interlayer thickness, because polarization charges increase the distance that carriers must tunnel. Simulations identify favorable parameter ranges. 相似文献
66.
Amira E.M. Abdallah Rafat M. Mohareb Ebtsam A. Ahmed 《Journal of heterocyclic chemistry》2019,56(11):3017-3029
Preparation of pyrano[2,3‐d]thiazole and thiazolo[4,5‐b]pyridine derivatives through multicomponent reactions (MCRs) was achieved by the reaction of 2‐(2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophen‐3‐yl)thiazol‐4(5H)‐one with various active methylene reagents such as ethyl cyanoacetate or malononitrile in basic conditions containing diverse aromatic aldehyde. Furthermore, this study aims to evaluate the in vitro cytotoxic activity of the synthetic compounds against six cancer cell lines, and all the prepared compounds revealed valuable activity compared with the CHS‐828, which is the 2‐[6‐(4‐chlorophenoxy)hexyl]‐1‐cyano‐3‐pyridin‐4‐ylguanidine as the standard drug. Some of the pyrano[2,3‐d]thiazole and thiazolo[4,5‐b]pyridine derivatives showed the highest antitumor activity towards the six cancer cell lines. Moreover, (c‐Met) enzymatic activity of the most potent compounds showed that compounds 3b 2‐(2‐amino‐4,5,6,7 tetrahydrobenzo[b]thiophen‐3‐yl)‐5‐hydroxy‐7‐(2‐hydroxy‐phenyl)‐7H‐pyrano[2,3‐d]thiazole‐6 carbonitrile and 5e 2‐(2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophen‐3‐yl)‐5‐hydroxy‐7‐phenyl‐4,7‐dihydrothiazolo[4,5‐b]pyridine‐6‐carbonitrile were with higher activities than foretinib. Three compounds were selected to examine their Pim‐1 kinase where compounds 3b and 7b showed the highest inhibitions. 相似文献
67.
Sabrin R. M. Ibrahim Hossam M. Abdallah Ali M. El-Halawany Alaa M. Nafady Gamal A. Mohamed 《Natural product research》2019,33(2):258-265
A new prenylated xanthone, mangostanaxanthone VIII (7) and six known metabolites: gartanin (1), 1,3,8-trihydroxy-2-(3-methyl-2-butenyl)-4-(3-hydroxy-3-methylbutanoyl)-xanthone (2), rubraxanthone (3), 1,3,6,7-tetrahydroxy-8-prenylxanthone (4), garcinone C (5), and xanthone I (9-hydroxycalabaxanthone) (6) were separated from the EtOAc-soluble fraction of the air-dried pericarps of Garcinia mangostana (Clusiaceae). Their structures have been verified on the basis of spectroscopic data analysis as well as comparison with the literature. The cytotoxic activity of 7 was assessed against MCF7, A549, and HCT116 cell lines using sulforhodamine B (SRB) assay. Compound 7 showed significant cytotoxic potential against MCF7 and A549 cell lines with IC50s 3.01 and 1.96 μM, respectively compared to doxorubicin (0.06 and 0.44 μM, respectively). However, it exhibited moderate activity towards HCT116 cell line. 相似文献
68.
Zaki Nadia G. Mahmoud Walaa H. El Kerdawy Ahmed M. Abdallah Abanoub Mosaad Mohamed Gehad G. 《Research on Chemical Intermediates》2020,46(6):3193-3216
Research on Chemical Intermediates - Reaction of cocaine (Cn) with Ln(III) chloride salts [where Ln?=?La(III), Er(III), and Yb(III)] afforded complexes of the [Ln(Cn)Cl(OH2)3].2Cl type... 相似文献
69.
International Journal of Theoretical Physics - The interaction between two modes quantized field and asymmetric two atoms represents one of the important quantum models to study the nonclassical... 相似文献
70.
Bouchra Belhaj Abdallah Ahmed Landoulsi Abdelwaheb Chatti 《Journal of Saudi Chemical Society》2018,22(1):110-118
The instant biosynthesis of silver nanoparticles under static electromagnetic induction, its antibacterial activity and its post exposure monitoring were reported here. A mix of silver nitrate solution and Ruta chalepensis leaf extract was irradiated by a static electromagnetic field (SMF) of 200 mT. The characteristics and stability of the biosynthesized silver nanoparticles (Ag NPs) were determined. Compared to the non-irradiated exposure, the morphology and state of the obtained material change once the exposition to SMF is turned off. Shifting from 453 to 473 nm, the percentage of the needles shaped silver nanoparticles increased and continue to win and dominate the biomixture toward the spherical silver nanoparticles. TEM microscopy showed a wide range of silver materials designed in different nanoscale morphology and beyond where they undergo major changes affecting mainly the size, shape and form (dispersity) of nanosilver. 相似文献