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61.
E. M. S. Azzam A. M. Badawi A. R. E. Alawady A. Soliman 《Journal of Dispersion Science and Technology》2013,34(4):540-547
The purpose of this work is to study the self-assembling of some synthesized thiol surfactants namely (mercaptopropane-, mercaptohexane-, mercaptooctane-, and mercaptodecane sodium sulfonate) on the fabricated gold nanoparticles. The self-assembling of these surfactants on gold nanoparticles characterized using different techniques such as FTIR spectroscopy, UV spectroscopy, and transmission electron microscopy (TEM). Spectroscopic evidence suggests that the synthesized thiol surfactants have been attached to the gold nanoparticles. The effect of self-assembling of these surfactants on the size of the gold nanoparticles was studied using TEM images. The growth of the gold nanoparticles was investigated with respect to the increase of alkyl chain in the synthesized thiol surfactants. The results show that the stabilization of gold nanoparticles was affected by the increase in alkyl chain length of these surfactants. The effect of gold nanoparticles on the interfacial tension and the emulsion stability of these surfactants with crude oil was studied. 相似文献
62.
Chemistry of Phosphorus Ylides. Part 37. The Reaction of Phosphonium Ylides with Indoles and Naphthofurans. Synthesis of Phosphanylidenes,Pyrans, Cyclobutenes,and Pyridazine as Antitumor Agents 下载免费PDF全文
Soher S. Maigali Marwa El‐Hussieny Fouad M. Soliman 《Journal of heterocyclic chemistry》2015,52(1):15-23
The reaction of the stabilized phosphonium ylides 2a , 2b with indolinones 1a , 1b and naphthofuranone 13 afforded the corresponding propylidene and ethylidene derivatives 4a , 4b , 4c , 4d and 14a , 14b . On the other hand, the active phosphacumulenes 5a , 5b react with compounds 4a , 4b , 4c , 4d by [4 + 2]‐cycloaddition to give the stable phosphanylidene indole pyranones 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h . Although compounds 14a , 14b afforded the naphthofuropyrans 16a , 16b , 16c , 16d and triphenylphosphane. Moreover, the phosphallene ylide 7 react with compounds 4a , 4b , 4c , 4d and 14a , 14b to give phosphanylidenecyclobuteneindoline 9a , 9b , 9c , 9d and naphthalenones 18a , 18b , respectively. In addition, the naphthofuropyridazine 21 was obtained from the reaction of the hydrazone 19 and the phosphacumulene 5a . The antitumor activity of some of the new compounds was evaluated, in vitro, against colon and hepatocellular carcinoma cell lines. They showed values closed to that recorded by the reference drug Doxorubicin. 相似文献
63.
In this article, based on a set of upper record values from a Rayleigh distribution, Bayesian and non-Bayesian approaches have been used to obtain the estimators of the parameter, and some lifetime parameters such as the reliability and hazard functions. Bayes estimators have been developed under symmetric (squared error) and asymmetric (LINEX and general entropy (GE)) loss functions. These estimators are derived using the informative and non-informative prior distributions for σ. We compare the performance of the presented Bayes estimators with known, non-Bayesian, estimators such as the maximum likelihood (ML) and the best linear unbiased (BLU) estimators. We show that Bayes estimators under the asymmetric loss functions are superior to both the ML and BLU estimators. The highest posterior density (HPD) intervals for the Rayleigh parameter and its reliability and hazard functions are presented. Also, Bayesian prediction intervals of the future record values are obtained and discussed. Finally, practical examples using real record values are given to illustrate the application of the results. 相似文献
64.
This article is devoted to the investigation and the construction of the Klein correspondence of line congruences referred to a specialized moving frame in a 3-dimensional elliptic spaceS
3 to the hyperquadricP
4 of the Klein 5-dimensional elliptic spaceS
5. The Klein correspondence is given and characterized by Theorems 1, 2. The methods adapted here are based on Cartan's differential calculus [1], [6]. 相似文献
65.
Al-Bahi Ali M. Soliman Abdelfattah Y. Mohamed Nader M. A. 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):323-330
Journal of Radioanalytical and Nuclear Chemistry - Neutron backscattering technique is investigated as an alternative way for measuring the level of water in the horizontal oil gravity separators.... 相似文献
66.
Ahmed A. Fadda Nesma M. Bayoumy Nanees N. Soliman Doaa M. Eldiasty 《Journal of heterocyclic chemistry》2019,56(2):597-607
Innovative poly‐substituted heterocyclic rings incorporating dioxoisoindoline ( 2 – 25 ) were synthesized through the reaction of dioxoisoindoline derivative 2 as starting compound with various types of reagents. All compounds were characterized by appropriate means of (1H‐NMR, 13C‐NMR, IR, and mass). The prepared compounds were evaluated as antimicrobial agents against Escherichia coli, Staphylococcus aureus, and Candida albicans microorganisms. The tested compounds exhibited low to moderate antibacterial activities and promising results as antifungal agents. 相似文献
67.
68.
Detailed results are presented for laminar film condensation from steam-air mixtures flowing downward in vertical flat-plate channels. The mixture flow is laminar and saturation conditions prevail at the inlet. A fully coupled implicit numerical approach is used that achieves excellent convergence behavior, even for high inlet gas mass fractions. The detailed results include velocity, temperature, and gas mass fraction profiles, as well as axial variations of film thickness, pressure gradient and Nusselt number. The effects of a wide range of changes in the four independent variables (the inlet-to-wall temperature difference and the inlet values of gas concentration, Reynolds number, and pressure) on the film thickness, axial pressure gradient, and the local and average Nusselt numbers are carefully examined. It was found that increases in inlet concentration of noncondensable gas caused significant decreases in the film thickness, local Nusselt number, and axial pressure gradient. An analytical solution for the film thickness and velocity field at the end of condensation path was developed and shown to be the asymptotic value of the numerical results for large distances along the channel. 相似文献
69.
Timothy N. Phillips Ibrahim M. Soliman 《Numerical Methods for Partial Differential Equations》1991,7(1):9-24
A spectral algorithm based on the influence matrix technique is desclibed for solving numerically the flow of incompressible viscous fluids. The algorithmic development is for both Newtonian and non-Newtonian flows. To investigate the performance of the method several test problems are solved. Accurate results are obtained with relatively few degrees of freedom. 相似文献
70.
A finite-volume-based numerical model for mixed-convection laminar film condensation from a flowing mixture of a vapor and
a heavier noncondensable gas on inclined isothermal flat plates is presented. The full boundary layer equations for the liquid
film and the vapor-gas mixtures (including liquid inertia and energy convection terms) are solved implicitly with appropriate
liquid-mixture interface conditions. Results were obtained for three mixtures, covering wide ranges of liquid Prandtl number
and free-stream gas concentration in the forced-convection, mixed-convection and free-convection flow regimes. The effects
of liquid inertia were found to be significant only for low-Prandtl-number fluids and lower gas concentrations. The effects
of liquid energy convection were found to be significant only for high-Prandtl-number fluids and to be most significant for
mixed-convection condensation.
Received on 3 March 1998 相似文献