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301.
302.
Abdou Saad EL-Tabl Fathey A. EL-Saied Ahmed Noman AL-Hakimi 《Transition Metal Chemistry》2007,32(6):689-701
MnII, FeIII, CoII, NiII, CuII, ZnII, LaIII, RuIII, HfIV, ZrIV and UVI complexes of 4-methylphenylamino acetoacetylacetone hydrazone have been synthesized and characterized by elementals analyses,
i.r., u.v.–vis. spectra, magnetic moments, conductances, thermal analyses (d.t.a and t.g.a) and e.s.r measurements. The i.r.
data show that, the ligand behaves as a neutral bidentate type (10), (13) and neutral tridentate type (4), (11), (12) and (21) monobasic bidentate type (7) or monobasic tridentate type (2), (3), (5), (6), (8), (14), (15), (16), (18), (19), (20) and (22) or dibasic tridentate type (5), (9) and (17) towards the metal ion. Molar conductances in DMF solution indicate that, the complexes are non-electrolytes. The e.s.r spectra
of solid complexes (8) and (10) show axial type spectra with
, d(x2-y2) ground state with significant covalent bond character. However, complex (12), shows an isotropic type, indicating a octahedral manganese(II) complex. Antibacterial and antifungal tests of the ligand
and some of its metal complexes are also carried out and it has been observed that, the complexes are more potent bactericides
and fungicides than the ligand. 相似文献
303.
Abbasi R Abdou Y Abu-Zayyad T Adams J Aguilar JA Ahlers M Andeen K Auffenberg J Bai X Baker M Barwick SW Bay R Bazo Alba JL Beattie K Beatty JJ Bechet S Becker JK Becker KH Benabderrahmane ML BenZvi S Berdermann J Berghaus P Berley D Bernardini E Bertrand D Besson DZ Bindig D Bissok M Blaufuss E Blumenthal J Boersma DJ Bohm C Bose D Böser S Botner O Braun J Brown AM Buitink S Carson M Chirkin D Christy B Clem J Clevermann F Cohen S Colnard C Cowen DF D'Agostino MV Danninger M Daughhetee J 《Physical review letters》2011,106(14):141101
IceCube has become the first neutrino telescope with a sensitivity below the TeV neutrino flux predicted from gamma-ray bursts if gamma-ray bursts are responsible for the observed cosmic-ray flux above 10(18) eV. Two separate analyses using the half-complete IceCube detector, one a dedicated search for neutrinos from pγ interactions in the prompt phase of the gamma-ray burst fireball and the other a generic search for any neutrino emission from these sources over a wide range of energies and emission times, produced no evidence for neutrino emission, excluding prevailing models at 90% confidence. 相似文献
304.
Abdou O. Abdelhamid Ahmed H. Elghandour Nora A. Rateb Ahmed M. Awad 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1637-1646
1-amino-4-methyl-4H-3-thia-4,5a,10-triazacyclopenta-[a]fluoren-5-one and 6-methyl-6H-,9H-thia-4b,6,9,11,12-pentaazaindeno[1,2-a]-fluorene-5,8-dione derivatives were prepared from 2-methyl-1-oxo-3-thioxo-2,4,9b-trihydropyrimidino[1,6-a] benzimidazole-4-carbonitrile. Also, 2,3-dihydro-1,3,4-thidazoles were synthesized via a reaction of hydrazonoyl chlorides with 3-(methylamino)-2-substituted 3-thioxopropanenitrile. Structures of newly synthesized compounds were elucidated on the basis of elemental analyses, spectral data, and alternative methods synthesis whenever possible. 相似文献
305.
Abdou O. Abdelhamid Ali A. Al-Atoom 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1629-1646
Abstract Thiazolylacetonitrile was used in the synthesis of coumarin, pyrazolo[4,3]pyrimidines, 1,3,4-thiadiazolines, aminothiophenes, and thiazoles in a good yields. Also, pyrazolo[4,5-d]triazolino[4,5-a]pyrimidines, pyrazolo[4,5-d]thiazolino[3,2-a]pyrimidines, and pyrazolo[4,5-d]tetrazolino[1,5-a]pyrimidines were synthesized from pyrazolo[4,5-d]pyrimidine. Structures of the newly synthesized were elucidated by elemental analysis, spectral data, and alternative synthesis routes whenever possible. Some synthesized compounds were tested for their antimicrobial activity. 相似文献
306.
Abdou O. Abdelhamid Ahmed H. Elghandour Ahmed M. Hussein Yasser H. Zaki 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2097-2109
Triazoles, thiadiazoles, and triazolo[4, 3-a]pyrimidines were synthesized via reaction of hydrazonoyl halides with each of 3-methyl-4-(methylthiothioxomethyl)-2-pyrazolin-5-one, 3-methyl-4-[methylthio(phenylamino)methyl]-2-pyrazolin-5-one, and pyrimidine-2-thiones. Structures of the newly synthesized compounds were elucidated on the basis of elemental analysis, spectral data, and alternative-methods synthesis whenever possible. 相似文献
307.
Wafaa M. Abdou Reham F. Barghash Mohamed S. Bekheit 《Monatshefte für Chemie / Chemical Monthly》2011,81(2):649-656
Abstract
Schiff-base Kabachnik–Fields intermediates generated in situ from substituted pyrazole-4-carbaldehyde and 2-aminothiophene derivatives were trapped by dialkyl phosphites to produce the corresponding α-aminophosphonates in moderate yields. The latter products could be also obtained in excellent yields (≥75%) by directly applying the phosphorus reagents to the Schiff bases. Next, dialkyl phosphites were applied to one of the parent aldehydes to give the expected α-hydroxyphosphonate derivatives. Applying hexaalkyl triamidophosphites to the Schiff base in ethanol afforded methylphosphonic diamide derivatives, whereas ring attack on the pyrazole ring occurred when the same amidophosphites were applied to the parent aldehyde to give the corresponding alkylidenephosphorane ylides in an open structure form in good yields. Some of the new compounds exhibited considerable anti-inflammatory properties. 相似文献308.
Anita Patel Gautam Pulugundla Sergey Smolentsev Mohamed Abdou Rajendraprasad Bhattacharyay 《Theoretical and Computational Fluid Dynamics》2018,32(2):165-178
Following the magnetohydrodynamic (MHD) code validation and verification proposal by Smolentsev et al. (Fusion Eng Des 100:65–72, 2015), we perform code to code and code to experiment comparisons between two computational solvers, FLUIDYN and HIMAG, which are presently considered as two of the prospective CFD tools for fusion blanket applications. In such applications, an electrically conducting breeder/coolant circulates in the blanket ducts in the presence of a strong plasma-confining magnetic field at high Hartmann numbers, \(\textit{Ha}\) (\(\textit{Ha}^2\) is the ratio between electromagnetic and viscous forces) and high interaction parameters, \(\textit{N}\) (\(\textit{N}\) is the ratio of electromagnetic to inertial forces). The main objective of this paper is to provide the scientific and engineering community with common references to assist fusion researchers in the selection of adequate computational means to be used for blanket design and analysis. As an initial validation case, the two codes are applied to the classic problem of a laminar fully developed MHD flows in a rectangular duct. Both codes demonstrate a very good agreement with the analytical solution for \(\textit{Ha}\) up to 15, 000. To address the capabilities of the two codes to properly resolve complex geometry flows, we consider a case of three-dimensional developing MHD flow in a geometry comprising of a series of interconnected electrically conducting rectangular ducts. The computed electric potential distributions for two flows (Case A) \(\textit{Ha}=515\), \(\textit{N}=3.2\) and (Case B) \(\textit{Ha}=2059\), \(\textit{N}=63.8\) are in very good agreement with the experimental data, while the comparisons for the MHD pressure drop are still unsatisfactory. To better interpret the observed differences, the obtained numerical data are analyzed against earlier theoretical and experimental studies for flows that involve changes in the relative orientation between the flow and the magnetic field. 相似文献
309.
Mohammed Kara Amine Assouguem Mohamed El Fadili Safa Benmessaoud Samar Zuhair Alshawwa Omkulthom Al Kamaly Hamza Saghrouchni Abdou Rachid Zerhouni Jamila Bahhou 《Molecules (Basel, Switzerland)》2022,27(3)
Vinegar is a natural product widely used in food and traditional medicine thanks to its physicochemical properties and its richness in bioactive molecules. However, its direct use by consumers can have complications and undesirable effects. Therefore, this study contributes to investigating the physicochemical and biological properties of eleven vinegars marketed in Morocco. Determination of pH, acetic acid, conductivity, total soluble solids and alcohol content in vinegar was carried out. The polyphenols (TP), flavonoids (TF), and condensed tannins (CT) content was determined, and their antioxidant activities were evaluated using 2,2-diphenyl-1-picryl Hydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP) and Phosphomolybdenum Reduction Assay (TAC). Then, the antimicrobial activity was studied against four pathogenic bacteria and two fungal strains, using the disk diffusion and the microdilution method. This study showed a wide range of acetic acid values from 0.65 ± 0.29 to 5.15 ± 0.20%. The high value of TP, TF, and CT in our samples V10, V9, and V4 was 655.00 ± 22.2 µgGAE/mL, 244.53 ± 11.32 µgQE/mL and 84.63 ± 1.00 µgTAE/mL, respectively. The tested strains showed variable sensitivities to the different samples with inhibition zones ranging from 6.33 ± 2.08 to 34.33 ± 0.58 mm. The lowest minimum inhibition concentrations were recorded against Staphylococcus aureus ATCC29213 ranging from 1.95 to 7.81 µL/mL. While Aspergillus niger ATCC16404 showed resistance against all of the analyzed samples. In general, vinegar commercialized in Morocco presents a variable range of products with variable properties. Indeed, must take into account this diversity when using it. A future study is needed to identify the phytochemical composition that will further the comprehension of this variability and contribute to its valorization. 相似文献
310.
在溶剂热条件下,合成了2个碱土金属配位聚合物[Ca (tdc)(DMF)2]n(1)和[Ba (tdc)]n(2)(H2tdc=2,5-噻吩二甲酸),分别用元素分析、红外光谱、X射线单晶衍射、粉末衍射、热重分析和荧光光谱对它们进行了表征。结构分析表明,配合物1具有4,4连接的二维层状结构,拓扑符号为(44·62),而配合物2呈现三维网络结构。固体荧光测试表明配合物1比配合物2具有更显著的荧光性能。 相似文献