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31.
An unprecedented one-pot reductive trimerization of aromatic aldehydes to 1,2,3-triaryl-2-propen-1-ones as well as tandem reductive coupling-rearrangements of aryl ketones to pinacolone analogues was efficiently achieved using tetrachlorosilane-zinc at room temperature. 相似文献
32.
M. B. Alamin A. A. Mhapes A. M. Bejey A. Sadek R. H. Atweer K. Dubali Daw M. Saad 《Journal of Radioanalytical and Nuclear Chemistry》2007,271(1):247-250
Since there is no database in Libya defining the intake of the individuals from different essential (minor and trace) and
toxic elements provided through food, drinking water and aerosol, a project has been proposed with the cooperation of IAEA
to determine the concentration of a number of elements such as Cs, Fe, Cr, Rb, Sc, Se, Co, Zn in the three mentioned sources.
Emphasis was placed on the use of nuclear and nuclear-related techniques. In this paper, the primary results are presented
for the concentration of minor and trace elements in some vegetables, spices and other foods which are widely used in the
Libyan meals. Instrumental neutron activation analysis utilizing a 10 MW water pool reactor and a γ-ray spectroscopy facility
was employed. For quality control, certified reference materials were analyzed simultaneosly with the samples which show good
agreements compared with the certified data. Emphasis was given to both elements iron and zinc for their importance. 相似文献
33.
Saad Zagloul Rida 《Applicable analysis》2013,92(1-2):93-102
We derive none some explicit formula for the power of fractional order (differential and integral) operators. 相似文献
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35.
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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37.
A tridentate Schiff base ligand, (E)‐3‐((2‐hydroxy‐3‐methoxybenzylidene)amino)‐2‐methylquinazolin‐4(3H)‐one [HL], and its mixed‐ligand Ni(II) complex [Ni(L)(imi)], were synthesized and fully characterized using elemental analysis, FT‐IR, UV–Vis and 1HNMR spectroscopy techniques. The structure of the synthesized ligand and complex was determined with single crystal X‐ray diffraction method. In the complex, a square planner geometry was observed around the Ni(II) central atom coordinated with the donor atoms of the Schiff base ligand and one nitrogen of imidazole group. In addition, the catalytic activity of the complex on the three‐component condensation of hydrazine hydrate with phthalic anhydride and dimedone to obtain 2H–indazolo[2,1‐b]phthalazine‐triones was investigated. Furthermore, in‐vitro antimicrobial studies were performed that indicated the great antibacterial activities of the Ni(II) complex against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus cereus bacteria. 相似文献
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39.
M. Saad I. F. Gilmutdinov A. G. Kiiamov D. A. Tayurskii S. I. Nikitin R. V. Yusupov 《JETP Letters》2018,107(1):37-41
The trapped magnetic flux in the finely ground pyrolytic graphite sample annealed at 670 K in air has been observed. Flux trapping occurs on cooling of the sample from room temperature to 10 K in a magnetic field of 1 T. The magnitude and sign of the induced trapped moment remain unchanged when the applied magnetic field is varied within ±1 T at T K. The trapped magnetic flux is manifested in the displacement of the magnetization curve relative to that of the sample cooled in zero field. Displacement magnitude gradually decreases with the temperature increase up to 350 K, not reaching zero. The set of experimental observations probably reflects the presence in the sample of a granular high-temperature superconducting phase. 相似文献
40.