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81.
Abdellah Bnouhachem 《Journal of Mathematical Analysis and Applications》2006,314(2):513-525
In this paper, we presented a new projection and contraction method for linear variational inequalities, which can be regarded as an extension of He's method. The proposed method includes several new methods as special cases. We used a self-adaptive technique to adjust parameter β at each iteration. This method is simple, the global convergence is proved under the same assumptions as He's method. Some preliminary computational results are given to illustrate the efficiency of the proposed method. 相似文献
82.
Abdellah Sebbar 《Communications in Mathematical Physics》1998,198(2):283-309
In this paper a close connection is established between certain cohomology spaces of representations of the quantum affine
algebra , and a twisted $q$-de Rham (Jackson–Aomoto) cohomology of configuration spaces using the quantum screening operators.
Received: 24 December 1997 / Accepted: 2 April 1998 相似文献
83.
Hossni Ziyat My Youssef Ait Itto Mustapha Ait Ali Abdellah Karim Abdelkhalek Riahi Jean‐Claude Daran 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):o90-o93
The two new gem‐dihalogenocyclopropanes (1′S,3R)‐3‐(2′,2′‐dichloro‐1′‐methylcyclopropyl)‐6‐oxoheptanoic acid, C11H16Cl2O3, (2), and (1′S,3R)‐3‐(2′,2′‐dibromo‐1′‐methylcyclopropyl)‐6‐oxoheptanoic acid, C11H16Br2O3, (3), are isostructural. Both present two stereogenic centers at C1′ and C3. The absolute configuration was determined by X‐ray methods. The cyclopropyl rings are unsymmetrical, the shortest bond being distal with respect to the alkyl‐substituted C atom. 相似文献
84.
In the first part of the present study, an appropriate inflow turbulent boundary condition is chosen. Then, a comparison is
made between two turbulence models for a plasma jet discharged into air atmosphere. The plasma jet gas phase flow is predicted
with the standard k–ɛ model and the RNG model of turbulence. Particles behavior is modeled using stochastic particles trajectories.
A validation of the plasma jet model is made by comparison with experimental data. This part of the study shows that the flow
features are better predicted with the RNG model. The choice of appropriate boundary conditions seems to be crucial for a
better simulation of plasma thermal spraying. Afterwards, computations are performed for projection of Ni particles. It is
found that the computed particles velocities and temperatures are also better predicted with the RNG model compared with the
k–ɛ model. The second part of this study is concerned with the effect of the substrate movement on the gas flow field. This
is performed in order to simulate a realistic coatings process where a relative movement between the torch and the substrate
always exists. Three substrate velocities have been used and it is found that the flow fields are affected only very near
the substrate wall. 相似文献
85.
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87.
Hachama Kamel Khadraoui Abdelkader Zouikri Mohamed Khodja Mohamed Khelifa Abdellah Echiker Khadidja Hammouti Belkheir 《Research on Chemical Intermediates》2016,42(2):987-996
Research on Chemical Intermediates - A new benzoxazin derivative, namely methyl 3-(2-oxo-2H-1,4-benzoxazin-3-yl) propanoate (1,4-MBXP), was synthesized under mild conditions from 2-aminophenols and... 相似文献
88.
Ali Oubella Abdoullah Bimoussa Abdellah Nait Oussidi Mourad Fawzi Aziz Auhmani Hamid Morjani Abdelkhalek Riahi Mhamed Esseffar Carol Parish Moulay Youssef Ait Itto 《Molecules (Basel, Switzerland)》2022,27(3)
Aseries of novel 1,4-disubstituted 1,2,3-triazoles were synthesized from an (R)-carvone terminal alkyne derivative via a Cu (I)-catalyzed azide–alkyne cycloaddition reaction using CuSO4,5H2O as the copper (II) source and sodium ascorbate as a reducing agent which reduces Cu (II) into Cu (I). All the newly synthesized 1,2,3-triazoles 9a–h were fully identified on the basis of their HRMS and NMR spectral data and then evaluated for their cell growth inhibition potential by MTS assay against HT-1080 fibrosarcoma, A-549 lung carcinoma, and two breast adenocarcinoma (MCF-7 and MDA-MB-231) cell lines. Compound 9d showed notable cytotoxic effects against the HT-1080 and MCF-7 cells with IC50 values of 25.77 and 27.89 µM, respectively, while compound 9c displayed significant activity against MCF-7 cells with an IC50 value of 25.03 µM. Density functional calculations at the B3LYP/6-31G* level of theory were used to confirm the high reactivity of the terminal alkyne as a dipolarophile. Quantum calculations were also used to investigate the mechanism of both the uncatalyzed and copper (I)-catalyzed azide–alkyne cycloaddition reaction (CuAAC). The catalyzed reaction gives complete regioselectivity via a stepwise mechanism streamlining experimental observations. The calculated free-energy barriers 4.33 kcal/mol and 29.35 kcal/mol for the 1,4- and 1,5-regioisomers, respectively, explain the marked regioselectivity of the CuAAC reaction. 相似文献
89.
Breast cancer is a deadly disease and the second largest cause of mortality on a worldwide platform. Despite the availability of several cancer treatments, life expectancies stay relatively poor. Consequently, the medicinal chemistry community prioritizes the quick discovery of novel anticancer drugs. In recent years, computational approaches have been widely used to accelerate the drug development process. In light of this, in the current work, we performed three-dimensional quantitative structure-activity relationships (3D-QSAR) and molecular docking analyses on thioquinazolinone derivatives with aromatase enzyme (PDB: 3S7S). External validation was used to validate the prediction capabilities of the generated model. The best CoMSIA (comparative molecular similarity indices analysis) model exhibited the significant values of , . These findings suggested that the electrostatic, hydrophobic and hydrogen bond donor and acceptor fields have a significant effect on inhibition of breast cancer. Thus, a number of innovative potent aromatase inhibitors were designed and their biological activities were predicted based on the best model. Furthermore, molecular docking studies were carried out for the designed compounds against breast cancer. Additionally, ADMET proprieties were used to evaluate drug-likeness of these novel drug candidates. The most active compounds found by these computational studies could be helpful for synthesis and testing as prospective future anti-cancer treatments. 相似文献
90.
Soufiane El Houssame Hafid Anane Larbi El Firdoussi Abdellah Karim 《Central European Journal of Chemistry》2008,6(3):470-476
The palladium(0) catalyzed amination of allylic acetates and carbonates derivatives from terpenic olefins was carried out
under mild conditions. The reaction offers a very good method for the preparation of allylic amines and thus to provide a
useful entry to new functionalized terpenic olefin products. The mechanism involving a formation of p-allyl-palladium intermediate
complex is in good agreement with the results obtained with the optically active substrates, as well as via an analysis of
the observed regio-and stereoselectivity.
相似文献