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1.
Kacimi Rachid Bourass Mohamed Toupance Thierry Wazzan Nuha Chemek Mourad El Alamy Aziz Bejjit Lahcen Alimi Kamel Bouachrine Mohammed 《Research on Chemical Intermediates》2020,46(6):3247-3262
Research on Chemical Intermediates - A theoretical study on four organic dyes based on bis(4-hexyloxy)triphenylamine as donor and electron acceptor cyanoacrylic acid with a... 相似文献
2.
Mohamed Hilmy Elnagdi Ramadan Maawad Abdel-Motaleb Mona Mustafa Mohamed Foad Zayed Eman Moustafa Kamel 《Journal of heterocyclic chemistry》1987,24(6):1677-1681
The behaviour of several 2-amino-3-cyano-4H-pyran derivatives toward a variety of nucleophilic reagents is reported. 相似文献
3.
In this paper, we apply Adomian decomposition method (shortly, ADM) to develop a fast and accurate algorithm of a special second-order ordinary initial value problems. The ADM does not require discretization and consequently of massive computations. This paper is particularly concerned with the ADM and the results obtained are compared with previously known results using the Quintic C2-spline integration methods. The numerical results demonstrate that the ADM is relatively accurate and easily implemented. 相似文献
4.
Samir Kamel 《先进技术聚合物》2004,15(10):612-616
Rice straw was employed for the preparation of lignocellulosic‐poly(vinyl chloride) (PVC) composites. The effect of pretreatment of rice straw, concentration of PVC, pressure as well as pressing temperature on the mechanical properties and water absorption was studied. Also, the effect of lignin as coupling agent on the mechanical properties and water absorption of composite was studied. Composites of rice straw comprising both PVC and a coupling agent offer superior properties compared to those made from only rice straw and PVC. The extent of improvement in the mechanical properties and dimensional stability of composites depended not only on the pretreatment of rice straw, concentration of PVC and lignin but also on pressure and pressing temperature. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
5.
A simple and sensitive kinetic method was developed for the determination of ritodrine hydrochloride in pharmaceutical preparations. The method is based upon a kinetic investigation of the oxidation reaction of the drug with alkaline potassium permenganate at room temperature for a fixed 12.5 min; the absorbance of the colored permenganate ion was measured at 609 nm. The absorbance concentration plots were rectilinear over the range of 1.6–11.2 μg mL?1 (r = 0.9992) with a minimum detectability of 0.096 μgmL?1 (2.88 × 10?7 M). The different experimental parameters affecting the development and stability of color were carefully studied and optimized. The determination of ritodrine hydrochloride by the fixed concentration and rate constant methods is also feasible with the calibration equations obtained, but the fixed time method has been found to be more applicable. The proposed method was applied successfully to the determination of ritodrine hydrochloride in tablets and ampoules with average recoveries of 100.37 ± 0.93% and 100.42 ± 0.87%, respectively. The results obtained were in good agreement with those obtained using a reference method for comparison. A proposal of the reaction pathway is also presented. 相似文献
6.
A new colorimetric method for the determination of carboxylic acids using bromocresol green reagent is established. The formed color follows Beer's Lambert law and is stable for 24 hr. The method is successfully applied for measuring the disappearance of volatile fatty acids in P. oxalicum culture media. The method is reproducable and is used also for the quantitative determination of carboxylic acids in Dowex 1-X8 eluates. A linear relationship between the pK1 of different carboxylic acids and the calculated molar extinction coefficients of the color formed at 440 nm is demonstrated. 相似文献
7.
Single molecule fluorescence resonance energy transfer has been extensively used to measure distance changes and kinetics in various biomolecular systems. However, due to complications involving multiple de-excitation pathways of the dyes, the absolute inter-dye distance information has seldom been recovered. To circumvent this we directly probe the relative variations in the quantum yield of individual fluorophores. B-DNA was used as a scaffold to position the donor (Cy3 or TMR) at precise distances from the acceptor (Cy5) within the Forster radius. We found that the variation in the Cy3 quantum yield is approximately 5 times larger than that of TMR. By taking into account the molecule-to-molecule variability in the acceptor/donor quantum yield ratio, the apparent fluorescence resonance energy transfer efficiencies were scaled to yield the theoretical values. We obtained very good agreement with a physical model that predicts distances along B-DNA. 相似文献
8.
Ali Raza Hala A. Hejazi Sami Ullah Khan M. Ijaz Khan Kamel Smida Iskander Tlili 《印度化学会志》2022,99(7):100568
In this investigation, a mixed convective nanoparticles fluid flow over an inclined plate is deliberated. The effects of slip boundary wall and magnetic field are also considered. The dimensionless governing system for the considered problem is attained by implementing recent definitions of fractional derivatives (FD). The generalized solution is obtained through the Laplace Transformation Scheme (LTS) for the momentum and thermal expressions. To improve the novelty and to demonstrate some more physical perception of the stated research work, some remarkable special cases of velocity distribution through CF and AB-fractional derivative concept are addressed, whose daily life implication is well known in the existing literature. Moreover, to evaluate the physical interest of the stated problem, the outcomes of the obtained system graphical illustrations are made by utilizing MATHEMATICA. As a result, we concluded that the aluminium oxide nanoparticles show more decaying behavior as compared to titanium oxide nanoparticles for temperature and velocity profile. Furthermore, both fields i.e., momentum and thermal distributions are increased with the help of rising estimations parameter. Current results report novel applications in enhancement of heat transfer, thermal engineering, chemical processes, engineering and electronics devices, solar systems, extrusion processes, fission reactions etc. 相似文献
9.
Yahan Cui Rong Deng Xiangshuai Li Xinghuo Wang Qiong Jia Emilie Bertrand Kamel Meguellati Ying-Wei Yang 《中国化学快报》1990,30(12):2291-2294
A multifunctional nanohybrid based on mesoporous silica nanoparticle and biocompatible polypeptide was fabricated for targeted and dual-responsive therapy of tumor cells. 相似文献
10.
Kamel Guedri Tahmoor Bashir A. Abbasi Waseh Farooq Sami Ullah Khan M. Ijaz Khan Mohammed Jameel Ahmed M. Galal 《印度化学会志》2022,99(9):100614
The electroosmotic peristaltic flow of modified hybrid nanofluid in presence of entropy generation has been presented in this thermal model. The Hall impact and thermal radiation with help of nonlinear relations has also been used to modify the analysis. The assumed flow is considered due to a non-uniform trapped channel. The properties of modified hybrid nanofluid model are focused with interaction of three distinct types of nanoparticles namely copper (, silver () and aluminum oxide ( The mathematical modeling and significances of entropy generation and Bejan number are identified. With certain flow assumptions, the governing equations are attained for optimized peristaltic electroosmotic problem. Widely used assumptions of long wave length and low Reynolds number reduced the governing equations in ordinary differential equations. The ND solver is flowed for the solution process. The physical significant of results is observed by assigning the numerical values to parameters. 相似文献