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11.
M. Gabr Kassem Farid S. G. Soliman 《Monatshefte für Chemie / Chemical Monthly》1983,114(11):1197-1203
The fusion of 2-acetamidonicotinic acid witho-toluidine,p-bromoaniline oro-chloroaniline afforded the corresponding 3-aryl-2-methyl-pyrido-[2,3-d]pyrimidin-4(3H)-ones (4), the 8-aza analogs of 3-aryl-2-methyl-4-quinazolinones, alongside 2-aminonicotinic acid. 2-Methyl-3-2(2-methylphenyl)-pyrido[2,3-d]pyrimidin-4(3H)-one (4a), the 8-aza analog of methaqualone, was converted to the 2-substituted styryl derivatives6 by condensation with some aromatic aldehydes and to the tricyclic system, 10-aza-5,6-dihydro-3-hydroxy-5-(2-methylphenyl)-2-substituted-1H-pyrido [1,2-a] quinazoline-1,6-diones (8) by reaction with monosubstituted bis-2,4,6-trichlorophenyl malonates. 相似文献
12.
A series of binary complexes of Zn(II), Hg(II), Pb(II), La(III), Ce(III), Th(IV) and UO2(II) with 3,5-dinitrosalicylic acid and 5-sulphosalicylic acid have been isolated and characterized. The solution equilibria of these complexes have been studied pH-metrically. The formation constants (log K) at 25±1°C and ionic strength of 0.2M NaClC4 have been calculated. Stability of the complexes formed in relation to ligand molecular structure and nature of the metal ion has been examined and discussed. 相似文献
13.
Tadros Soad M. Soliman Yasser S. Beshir W. B. Saad Gamal R. Ali LailaI. 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):463-473
Journal of Radioanalytical and Nuclear Chemistry - Radiation-induced Ag° nanoparticles (NPs) in silver nitrate gel dosimeter incorporating various components was investigated in the dose range... 相似文献
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M. Mostafa A. F. El-gharbawy M. A. El-Absy S. E. Soliman F. A. Aly 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(3):1089-1097
A radiochemical method was investigated for separation and preconcentration of radioiodine from alkaline radiotellurium waste solution as Ag125I followed by recovery of 125I into aqueous NH3 solution and final purification by wet distillation. 125I–123mTe radiotracer solution (5 M NaOH) was equilibrated with prepared silver granules for different times and it was found that 125I was quantitatively removed from the aqueous phase after 7.0 h. The 125I-loaded silver was then equilibrated with ammonia solution in the presence of one of different reducing agents (namely, sodium borohydride, dextrose and zinc dust). Different concentrations of NH3 solution and reducing agents were studied. Quantitative recovery of 125I in the aqueous phase was achieved after 1.0 h of equilibration of 125I-loaded silver granules with 2.7M NH3 solution in the presence of Zn dust with a Zn:Ag molar ratio of 0.5. Purification of the recovered 125I was carried out by wet distillation from 20 % H2SO4 in the presence of H2O2. The distilled off 125I was received in a mixture solution of 0.1M NaOH and 0.01M Na2S2O3 with a radionuclidic purity of ≥99.99 %, radiochemical purity of ~98.8 % (as I? anions) and pH-value of ~13. 相似文献
16.
Phase transitions, structures, and rheological properties of hydroxypropyl cellulose–ethylene glycol and ethyl cellulose–dimethylformamide systems in the presence and in the absence of a magnetic field have been studied. The application of the magnetic-field results in increases in viscosity and supramolecular particle size in solutions of cellulose ethers. Concentration dependences of viscosity and particle size are described by curves with maxima. 相似文献
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A. M. M. Soliman A. Khodairy E. A. Ahmed 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):649-665
The reaction of N-chloroacetyl derivatives 6-10 with morpholine yielded N-morpholin-1-yl acetyl derivatives 11-15 , which were subjected to Thorpe-Zieler cyclization with sodium tert -butoxide to produce the corresponding condensed pyridin-2(1H)-one derivatives 16-20 . Treatment of compounds 1 , 6-10 with either malononitrile or p -chlorobenzylidinemalononitrile in presence of triethylamine, afforded the corresponding pyrimidines 21-25 , 27 and pyridine derivative 26 respectively. Moreover compound 1 a was treated with ethyl isothiocyanoacetate to give the corresponding piprazine derivative 28 . 相似文献