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A. A. Naqvi Faris A. Al-Matouq F. Z. Khiari Khateeb-ur-Rehman M. A. Gondal A. A. Isab 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):215-221
A thermal neutron capture-based Prompt Gamma ray Activation Analysis setup has been designed to analyze the elemental concentration of environmental bulk samples using a D(d,n) reaction-based portable neutron generator. The performance of the setup was tested through mercury concentration measurements in Hg-contaminated water samples using a large volume cylindrical bismuth germinate (BGO) gamma ray detector. Excellent agreement of experimental count rate of 2.64, 3.19 + 3.29 and 4.67–5.05 MeV Hg prompt gamma rays with theoretical count rate obtained through Monte Carlo simulations, indicates excellent performance of the newly designed portable neutron generator-based PGNAA setup. 相似文献
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A. A. Naqvi F. Z. Khiari Fatai A. Liadi Khateeb-ur-Rehman M. Raashid A. A. Isab 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(3):475-480
Prompt gamma ray analysis of soil samples contaminated with petroleum hydrocarbons(PHC) like benzene was carried out using 14 MeV neutron beams. Intensities of silicon, carbon, oxygen, and hydrogen gamma rays were measured for soil samples containing 2.20–10.4 wt% benzene. With increasing benzene concentration, the intensity of the C gamma rays increased while those of Si, H, and O gamma rays decreased. The reduction in Si, H, and O gamma ray intensities may be due to increasing neutron moderation effect in benzene-contaminated soil samples. The experimental intensities of gamma rays are in good agreement with the calculated intensities.The neutron moderation effects in benzene contaminated soil samples are about 26% weaker than those reported for soil samples containing moisture. From the slopes of silicon gamma ray intensity as a function of benzene concentration as well as moisture concentration, a simple scheme has been suggested to correct for the loss in carbon counts caused by neutron moderation from PHC and moisture in the soil samples. 相似文献
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Fayçel Jemmezi Samar Chtiba Jameleddine Khiari 《Journal of heterocyclic chemistry》2013,50(2):206-208
The symmetrical vinamidinium salts were allowed to react with malononitrile in refluxing ethanol in the presence of ammonium acetate for 12 h to afford the 2‐amino‐5‐aryl or formylpyridine‐3‐carbonitriles. 相似文献
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β‐Keto‐amides react with 2‐dimethylaminomethylene‐1,3‐bis(dimethylimonio)propane diperchlorate salt to give the corresponding 3‐acetyl‐5‐formylpyridin‐2‐ones. The annulation reactions proceed with excellent yields. 相似文献
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An expedient method for the synthesis of 2-phenyl-5-aryl-2,3-dihydropyrazolo[3,4-b]pyridin-3-ones and 2-phenyl-3-oxo-2,3-dihydropyrazolo[3,4-b]pyridine-5-carbaldehyde in a single-step via condensation of vinamidinium salts with 3-amino-1-phenyl-2-pyrazolin-5-one is described. 相似文献
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The cyclocondensation of vinamidinium salts with 5-aminotetrazole in basic media affords regiospecifically good yields of 2-(N, N-dimethylamino)-5- aryl-, arylsulfonyl- and 2-(N, N-dimethylamino)-5-formyl-pyrimidines, respectively. 相似文献
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A. Aksoy F. Z. Khiari A. Rahman 《Journal of Radioanalytical and Nuclear Chemistry》1998,230(1-2):75-79
The elemental analysis of Pt-Re/alumina catalysts was carried out by nondestructive and bulk neutron activation analysis.
Samples were irradiated with a241Am-Be source-based as well as accelerator-based thermal neutrons and induced activities were measured by a HPGe detector with
a PC-based data acquisition and analysis system. An appropriate calibration technique was established for the determination
of the respective ratios of each element present in the catalysts. The technique proved to be useful for the determination
of low concentrations of Pt and Re in the catalyst samples. 相似文献