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102.
H. S. Abd-Elghaffar M. A. El-Hashash S. F. Mohamed A. A. Ibrahim A. E. Amr M. A. Al-Omar E. S. Nossier 《Russian Journal of General Chemistry》2020,90(4):686-696
A new series of fused 1,3-indandione derivatives has been synthesized and evaluated for anti-proliferative activity. 2-Alkene-1,3-indandione derivatives have been used as the precursors of a number of tricyclic compounds. The latter have been tested for anti-proliferative activity. 相似文献
103.
Mohamed E. Mahmoud Amr A. Yakout Somia B. Ahmed Maher M. Osman 《International journal of environmental analytical chemistry》2013,93(14):1017-1031
A method is proposed and explored for speciation of Cr(III) and Cr(VI), selective extraction and preconcentration in various water samples based on dynamic and static techniques. Three newly designed alumina phases-physically adsorbed-2-pyridenecarboxyladehyde-thiosemicarbazone [Al-2PC-TSC (I–III)] were synthesised and characterised. Stability tests and application of [Al-2PC-TSC (I–III)] as inorganic ion exchangers and chelating solid sorbents for various metal ions were studied and evaluated. The distribution coefficient and separation factors of chromium species versus other interfering metal ions were determined to examine the incorporated selectivity into these alumina phases. Quantitative recovery of Cr(VI) was accomplished by [Al-2PC-TSC (I–III)] at pH = 1.0 while Cr(III) was found to be quantitatively recovered on these sorbents at pH = 7.0 with minimal or no interference between these two species under the studied buffering conditions. Selective solid phase speciation and preconcentration of Cr(III) and Cr(VI) in various real water samples were successfully performed and accomplished via a micro-column, with 200 as a preconcentration factor. Selective speciation of Cr(VI) and Cr(III) via preconcentration from seawater and industrial water samples by alumina phases in pH = 1 was found to give percentage recovery values of Cr(VI) in the range 93.5–97.3 ± 3.0–5.0% and 94.0–97.5 ± 3.0–4.0%, for seawater and industrial water samples, respectively. 相似文献
104.
An Efficient One‐pot Synthesis of Novel Spiro Cyclic 2‐Oxindole Derivatives of Pyrimido[4,5‐b]Quinoline,Pyrido[2,3‐d:6,5‐d′]Dipyrimidine and Indeno[2′,1′:5,6]Pyrido [2,3‐d]Pyrimidine in Water
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Amr Mohamed Abdelmoniem Huwaida M. E. Hassaneen Ismail Abdelshafy Abdelhamid 《Journal of heterocyclic chemistry》2016,53(6):2084-2090
A novel and facile one‐pot synthesis of spiro cyclic 2‐oxindole derivatives of pyrimido[4,5‐b]quinoline‐4,6‐dione, pyrido[2,3‐d:6,5‐d′]dipyrimidine‐2,4,6‐trione, and indeno[2′,1′:5,6]pyrido [2,3‐d]pyrimidine employing 6‐aminothiouracil (or 6‐aminouracil), isatin, and cyclic 1,3‐diketone (e.g. 1,3‐indanedione, dimedone, or barbituric acid) has been developed. 相似文献
105.
Othman Amr M. Ghobashy Mohamed Mohamady Abd El‐Sattar Nour E. A. 《Journal of Sol-Gel Science and Technology》2021,98(3):593-604
Journal of Sol-Gel Science and Technology - In this article, the first aerogels synthesis through cross-linked polyacrylamide (PAAm) hydrogel was reported through the use of gamma irradiation... 相似文献
106.
Mohamed Amr Fahim Asmaa M. Ibrahim Samah Abd Elhamead Ibrahim Medhat A. 《Structural chemistry》2021,32(6):2115-2138
Structural Chemistry - In this investigation, we elucidate the potential interaction of volatile organic solvents such as acetone and ethanol with adrenaline hormone through hydrogen bonding. There... 相似文献
107.
A recently derived Airy beam solution to the (1+1)D paraxial equation is shown to obey two salient properties characterizing arbitrary finite energy solutions associated with second-order diffraction; the centroid of the beam is a linear function of the range and its variance varies quadratically in range. Some insight is provided regarding the local acceleration dynamics of the beam. It is shown, specifically, that the interpretation of this beam as accelerating, i.e., one characterized by a nonlinear lateral shift, depends significantly on the parameter a entering into the solution. 相似文献
108.
Amr M. Shaarawi 《Foundations of Physics》2000,30(11):1911-1941
In this work, a Clifford algebra approach is used to introduce a charge-current wave structure governed by a Maxwell-like set of equations. A known spinor representation of the electromagnetic field intensities is utilized to recast the equations governing the charge-current densities in a Dirac-like spinor form. Energy-momentum considerations lead to a generalization of the Maxwell electromagnetic symmetric energy-momentum tensor. The generalized tensor includes new terms that represent contributions from the charge-current densities. Stationary spherical modal solutions representing the charge-current densities and the associated self-fields are derived. The use of a Clifford type dependence on time results in a distinct symmetry between the magnetic and electric components. It is shown that, for such spherical modes, the components of the force density deduced from the generalized energy-momentum tensor can vanish under certain conditions. 相似文献
109.
This study is interested in the illustration of ab initio potential energy curves for Ba+Arn (n = 1–4) clusters. The electronic structures of these molecules are calculated using [Ba2+] and [Ar] non-empirical core pseudo-potentials complemented by the core polarisation operators for both atoms, which allow the consideration of core valence correlation effects. The structure and stabilities of Ba+Arn (n = 1–4) clusters are investigated. These molecules are treated as one-electron active system. Spectroscopic constants and vibrational energy levels have been derived from their potentials. The analysis of the geometric forms, basing on the potential energy curves and the spectroscopic constants, clearly shows the importance of rare gas induced dipole. We also show that the dipolar interactions can influence the coupling between atoms. 相似文献
110.
The use of carboxylated graphene oxide (CGO) in the removal of organic pollutants from aquatic life is a recent and significant issue. In this study, EDTA-functionalized magnetite-carboxylated graphene oxide nanocomposite (EDTA-MCGO) was first used for the adsorptive removal of p-phenylenediamine (PDA) from industrial wastewaters. Based on the great surface area of the magnetic nanocomposite and the huge number of carboxyl groups from CGO and EDTA, multiple interactions to adsorb PDA can be anticipated. The maximum adsorption capacity of EDTA-MCGO was 994.75?mg g?1 at pH 7.8 and this value was decreased to 94.7% after seven cycles. The adsorption process was spontaneous and fits the pseudo-second-order kinetic model. PDA strongly deposited on the EDTA-MCGO surface via different electrostatic interactions and hydrogen bonding. The PDA removal efficiency from different environmental wastewaters was 98.6?±?0.6%. All the results demonstrate that the EDTA-MCGO nanocomposite is a potential magnetic extractor of aromatic contaminants from aquatic life.GRAPHICAL ABSTRACT 相似文献