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141.
Wassim Kriaa Kamel Abderrazak Hatem Mhiri Georges Le Palec Philippe Bournot 《Heat and Mass Transfer》2008,44(9):1051-1063
In this work, we propose to study non isothermal air–air coaxial jets with two different approaches: parabolic and elliptic
approaches. The standard k−ε model and the RSM model were applied in this study. The numerical resolution of the equations governing this flow type was
carried out for: the parabolic approach, by a “home-made” CFD code based on a finite difference method, and the elliptic approach
by an industrial code (FLUENT) based on a finite volume method. In forced convection mode (Fr = ∞), the two turbulence models are valid for the prediction of the mean flow. But for turbulent sizes, k−ε model gives results closer to those achieved in experiments compared to RSM Model. Concerning the limit of validity of the
parabolic and elliptic approaches, we showed that for velocities ratio r lower than 1, the results of the two approaches were satisfactory. On the other hand, for r > 1, the difference between the results became increasingly significant. In mixed convection mode (Fr ≅ 20), the results obtained by the two turbulence models for the mean axial velocity were very different even in the plume
region. For the temperature and the turbulent sizes the two models give satisfactory results which agree well with the correlations
suggested by the experimenters for X ≥ 20. Thus, the second order model with σ
t = 0.85 is more effective for a coaxial jet study in a mixed convection mode. 相似文献
142.
Seif-Eddine Djouad Malika Berredjem Fatima Zohra Hadjadj Aoul Fouzia Bouchareb Meriem Guerfi Taibi Ben Hadda Mohamed Aissaoui Billel Belhani 《印度化学会志》2022,99(9):100650
Cancer is one of the most serious health problems worldwide, affecting individuals from different sexes, ages, and races. However, the most frequent cancer types in the world are lung, prostate, stomach, colorectal, and esophagus in men; and breast, lung, stomach, colorectal and cervical in women. Currently, the search for new active substances used in oral targeted therapies are legitimate and opens up the possibility of an "ambulatory shift" in cancer treatment. In order to design anti-tumor drug candidates endowed with oral bioavailability, we studied trough an in silico approach the oral bioavailability of newly synthesized biomolecules; α-sulfamidophosphonates and α-amidophosphonates as well as their mechanism of action on the new target urokinase-type plasminogen activator (uPA). The studied compounds have been found to meet the five criteria of. Lipinski's rule. The Osiris, Molinspiration and SWISS/ADME calculations related to the compounds (1d, 2a) have shown that these compounds could be good candidates for interacting with the different targets, they have convincing characteristics in relation to the standard drug used. It can be concluded that these compounds are biologically important and possessing molecular properties desirable for being a drug candidate for oral use.The molecular docking results of the studied compounds revealed a good ligand-target interactions, the compounds (1d, 2a) presented a possibility of interacting as an inhibitor of the anticancer target: urokinase-type plasminogen activator (uPA). 相似文献
143.
Kızılaslan Abdulkadir Efe Şükran Akbulut Hatem 《Journal of Solid State Electrochemistry》2020,24(10):2279-2288
Journal of Solid State Electrochemistry - The preparation of different cathode composites with intimate contact between the components is of great importance to obtain batteries with better... 相似文献
144.
Hatem M. Titi Mihails Arhangelskis Giovanni P. Rachiero Tomislav Fri
i Robin D. Rogers 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(51):18570-18575
We demonstrate a co‐crystal‐based strategy to create new solid hypergols, that is, materials exhibiting spontaneous ignition when in contact with an oxidant, from typically non‐hypergolic fuel molecules. In these materials, the energy content and density can be changed without affecting the ignition delay. The use of an imidazole‐substituted decaborane as a hypergolic “trigger” component in combination with energy‐rich but non‐hypergolic nitrobenzene or pyrazine yielded hypergolic co‐crystals that combine improved combustion properties with ultrashort ignition delays as low as 1 ms. 相似文献
145.
Communications in Mathematical Physics - We consider a blow-up solution for the semilinear wave equation in N dimensions, with subconformal power nonlinearity. Introducing $${\mathcal{R}_0}$$ the... 相似文献
146.
Hatem A. Elbatal Zeinab S. Mandouh Hamdia A. Zayed Samir Y. Marzouk Gihan M. Elkomy Ahmed Hosny 《Journal of Non》2012,358(15):1806-1813
This research aims to investigate and compare the structural and the morphological properties of both lithium disilicate glasses doped with copper oxide and their glass–ceramic derivatives. Density measurements were measured for all samples by Archimedes method at room temperature. Differential scanning calorimetric analysis was used to determine the glass transition temperature (Tg) and crystallization temperature (Tc) for all glasses. The glass transition temperature was observed to decrease with increasing CuO concentration indicating the formation of non-bridging oxygen bonds in the glass network. X-ray analysis patterns reveal the appearance of crystalline lithium metasilicate phase as the main phase within the glass–ceramic derivatives, and their crystallite sizes were observed to decrease as the CuO increased. Experimental infrared absorption data indicate the existence of characteristic vibrational bands due to structural building SiO4 units in resemblance to the same vibrations observed from traditional crystalline silicates. Scanning electron microscopic investigations show the vitreous nature for lithium disilicate glasses and the distinct crystalline morphological features for the corresponding glass–ceramic derivatives. 相似文献
147.
Hatem Mejjaoli 《Applicable analysis》2013,92(9):1980-2007
In this article we characterize the Dunkl–Besov spaces and prove the embedding Sobolev theorems via the Dunkl heat semigroup. We also study the dispersive properties of the solutions of the Dunkl heat equation. Furthermore, we consider a few applications of these results to the corresponding nonlinear Cauchy problems on generalized functional spaces. 相似文献
148.
We consider the semilinear wave equation with power nonlinearity in one space dimension. Given a blowup solution with a characteristic point, we refine the blowup behavior first derived by Merle and Zaag. We also refine the geometry of the blowup set near a characteristic point and show that, except for perhaps one exceptional situation, it is never symmetric with respect to the characteristic point. Then, we show that all blowup modalities predicted by those authors do occur. More precisely, given any integer k ≥ 2 and $\zeta _0 \in {\cal R}$ , we construct a blowup solution with a characteristic point a such that the asymptotic behavior of the solution near (a,T(a)) shows a decoupled sum of k solitons with alternate signs whose centers (in the hyperbolic geometry) have ζ0 as a center of mass for all times. © 2013 Wiley Periodicals, Inc. 相似文献
149.
Mahmoud. M. M. Ramiz Ibrahim. S. Abdel Hafiz Mohamed. A. M. Abdel Reheim Hatem M. Gaber 《中国化学会会志》2012,59(1):72-80
A series of new pyrazolone and pyrazole derivatives with expected antifungicidal activity have been prepared through the reactions 3‐phenyl‐1‐H‐pyrazol‐5(4H)‐one ( 3 ) and 4‐(dimethylaminomethylene)‐3‐phenyl‐1H‐pyrazol‐5(4H)‐one ( 5 ) with a variety of electrophilic reagents and nucleophilic reagents. The newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral studies. 相似文献
150.
We consider the semilinear wave equation in the radial case with conformal subcritical power nonlinearity. If we consider a blow-up point different from the origin, then we exhibit a new Lyapunov functional which is a perturbation of the one-dimensional case and extend all our previous results known in the one-dimensional case. In particular, we show that the blow-up set near non-zero non-characteristic points is of class C1, and that the set of characteristic points is made of concentric spheres in finite number in for any R>1. 相似文献