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31.
Al-Noaimi Mousa Awwadi Firas F. Hammoudeh Ayman Tanash Maha 《Transition Metal Chemistry》2019,44(4):355-367
Transition Metal Chemistry - Eight ruthenium complexes having thioalkyl-azoimine (SNN) ligands of two general types have been synthesized: (a) [Ru(L)(bipy)Cl](PF6) where {bipy = bipyridine,... 相似文献
32.
Structural Chemistry - The [4+2] cycloaddition reaction of 1,3-dimethylindole and ortho-quinone methide (obtained from tautomerization of 2,6-dimethylquinone under basic conditions), experimentally... 相似文献
33.
Russian Journal of Applied Chemistry - Industrial by product dumped from iron making industry (slag) has been modified by various chemical agents, particularly, paraffin wax, liquid nitrile... 相似文献
34.
Mostafa Khajeh Maryam Dahmardeh Mousa Bohlooli Ali Khatibi Mansour Ghaffari-Moghaddam 《Journal of Dispersion Science and Technology》2018,39(3):311-315
In this work, an electromembrane extraction (EME) technique was used for the extraction and determination of gold from water samples prior to UV-Vis spectrophotometry. An artificial neural network (ANN) combined with imperialist competitive algorithm (ICA) has been applied to optimize the EME. The effective parameters including pH of acceptor phase, extraction time (t), volume of sample solution (V), stirring rate (S), and voltage (E) were chosen as input variables and the extraction recovery of gold was considered as output variable. The mean of squared error (i.e., 0.0009) and determination coefficient (i.e., 0.9821) were applied to estimate the performance of the ANN model. The limit of detection was 4.5?µg L?1 (S/N?=?3) on the optimized variables. The intra- and interday precisions (%) were found to be 6.7% and 2.6%, respectively. This technique was then applied for analysis of gold from environment water samples. 相似文献
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36.
Mousa Al-Noaimi Ismail I. Fasfous Firas F. Awwadi Deeb Taher Abdallah Alfayyoumi Obadah S. Abdel-Rahman 《Transition Metal Chemistry》2016,41(7):795-805
Five octahedral ruthenium(II) complexes with azoimine–quinoline (Azo) and α-diimine (L) ligands having the general formula [RuII(L)(Azo)Cl](PF6) (1–5) {Azo: PhN=NC(COMe)=NC9H6N, L = 4,4′-dimethoxy-2,2′-bipyridine (dmeb) (1), 4,4′-di-tertbutyl-2,2′-bipyridine (dtb) (2), 1,10-phenanthroline (phen) (3), 5-chlorophenanthroline (Clphen) (4), or 3,4,7,8-tetramethyl-1,10-phenanthroline (tmphen) (5)} were prepared by stepwise addition of the tridentate azoimine (H2Azo) and α-diimine (L) pro-ligands to RuCl3 in refluxing EtOH. The tridentate azoimine–quinoline ligands coordinate to ruthenium via the Azo-N′, N′-imine and N″-quinolone nitrogen atoms. The spectroscopic properties (IR, UV/Vis, 1H, 13C and 19F NMR) and electrochemical behavior of complexes 1–5 and the X-ray crystal structures of complexes 2 and 3 are presented. The coordination of Ru(II) to these strong π-acceptor ligands (Azo and L) results in a large anodic shift for the Ru(III/II) couples of 1.63–1.72 V versus NHE. The electronic spectra in MeCN and IR spectra in CH2Cl2 for complex 3 in its oxidized 3 + and reduced 3 ? forms were investigated. The calculated absorption spectrum of 3 in MeCN was used to assign the UV–Vis absorption bands. 相似文献
37.
Fathi A. Abu‐Shanab A. M. Hessen S. A. S. Mousa 《Journal of heterocyclic chemistry》2007,44(4):787-791
Polysubstituted pyridines 11a,c and 12 were prepared by the reaction of benzoylacetone with dimethylformamide dimethyl acetal followed by treatment with cyanothioacetamide 9a , cyanoacetamide 9b and the anion of malononitrile dimmer 9c in dry DMF. When the reaction was carried out in ethanol as a solvent and piperidine as a base afforded 14a,b . Thienopyridines 16a,b were prepared by the reaction of pyridinethiones 11a and 14a with 2‐chloro‐N‐p‐tolyl‐acetamide ( 15 ). Further reaction of thienopyridines 16a,b with either DMFDMA or nitrous acid to gave 17a,b and 18a,b respectively. The reaction of pyridine derivative 11c with hydrazine and phenylhydrazine afforded the tricyclic compounds 19a,b . 相似文献
38.
Mahmoud H. Saleh Nidal M. Ershaidat Mais Jamil A. Ahmad Basim N. Bulos Mousa M. Abdul-Gader Jafar 《Optical Review》2017,24(3):260-277
Spectral dispersions of index of refraction \({n(\lambda )}\) and extinction coefficient \({\kappa (\lambda )}\) of undoped amorphous selenium (a-Se) films of three thicknesses (d?≈?0.5, 0.75, and 1.0 µm) were evaluated by analyzing experimental room-temperature normal-incidence transmittance-wavelength (\({{T_{{\text{exp}}}}(\lambda )} - \lambda\)) data (λ =?400–1100 µm) of their air-supported {a-Se film/thick glass slide}-stacks using Swanepoel’s transmission envelope theory of uniform films. Above a wavelength \({{\lambda _c}\,\, \approx \,\,640\;{\text{nm}}}\), as-measured \({{T_{{\text{exp}}}}(\lambda )}\,\, - \,\lambda\) spectra display well-resolved maxima and minima, with minor shrinkage in transparent and weak absorption regions (750–1100 nm). Below \({\lambda _{\text{c}}}\), a smeared sharp decline of \({{T_{{\text{exp}}}}(\lambda )}\) with decreasing λ, signifying strong absorption in a-Se films and existence of band-tail localized states. For λ > λ c, the \({n\,(\lambda )}\, - \,\lambda\) data retrieved from algebraic envelope procedures followed a Sellmeier-like dispersion relation, with the best-fit values of high-frequency dielectric constant \({{\varepsilon _\infty }\, \approx \,\,{\text{4.9}}}\), static index of refraction \({{n_{\text{0}}} = n\left( {E\, \to \,{\text{0}}} \right)\,\, \approx \,\,{\text{2.43}}}\), and resonance wavelength \({{\lambda _0}\, \approx \,490\,\,{\text{nm}}}\), which may be assigned to onset of photogeneration in a-Se. Urbach-like dependency of absorption coefficient \({\alpha (h{{\nu }})}\) of a-Se films on photon energy \({h{{\nu }}}\) was realized with an Urbach-tail breadth of 85 meV. All achieved optical parameters were found to be slightly dependent on film thickness. Findings of present algebraic analysis are consistent with reported literature results obtained on the basis of other optical analytical approaches. 相似文献
39.
Mahmoud Sunjuk Mousa Al-Noaimi Ghassan Abu Sheikha Ekkehard Lindner Bassam El-Eswed Kamal Sweidan 《Polyhedron》2009
Water-soluble functionalized bis(phosphine) ligands L (a–h) of the general formula CH2(CH2PR2)2, where for a: R = (CH2)6OH; b–g: R = (CH2)nP(O)(OEt)2, n = 2–6 and n = 8; h: R = (CH2)3NH2 ( Scheme 1), have been prepared photochemically by hydrophosphination of the corresponding 1-alkenes with H2P(CH2)3PH2. Water-soluble palladium complexes cis-[Pd(L)(OAc)2] (1–8) were obtained by the reaction of Pd(OAc)2 with the ligands a–h in a 1:1 mixture of dichloromethane:acetonitrile. The water-soluble phosphine ligands and their palladium complexes were characterized by IR, 1H and 31P NMR. A crystallographic study of complex 1 shows that the Pd(II) ion has a square planar coordination sphere in which the acetate ligands and the diphosphine ligand deviate by less than 0.12 Å from ideal planar. 相似文献
40.