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81.
82.
M. A. Abuzeid M. I. El-Zaiki N. A. Mansour A. I. Popov H. R. Saad V. E. Storizhko 《Zeitschrift für Physik A Hadrons and Nuclei》1967,199(5):506-517
Total yields and angular distributions of gamma rays following the inelastic scattering of protons from Cr50 and Cr54 have been measured at proton energies below 2.5 MeV. Gamma ray spectra resulting from the proton radiative capture by Cr50 and Cr54 were obtained. Transitions from most of the Mn51 and Mn55 low-lying levels have been observed. The experimental results are in good agreement with predictions of the statistical compound nucleus theory. 相似文献
83.
M. M. Ayad M. I. Ayad I. A. Mansour 《Monatshefte für Chemie / Chemical Monthly》1993,124(10):995-1003
Summary Solvated oxovanadium(IV) complexes of Schiff bases derived from aromatic diamines and 2-hydroxy-1-naphthaldehyde have been prepared from ethanolic medium. The elemental analyses reveal that the complexes have the ratio 1:1, 2:2 and 1:2 (ligand:metal) composition which are nonelectrolyte inDMF. The coordination number six (octahedral geometry) is proposed for the complexes prepared. This is based on the results of IR, electronic and EPR spectra. TGA as well as DTA studies and the electrical properties and (I–V) characteristics for the metal complexes were investigated.
Synthese und thermische bzw. elektrochemische Untersuchungen an solvatisierten Oxovanadium(IV)-Komplexen mit Schiff-Basen aus aromatischen Diaminen und 2-Hydroxy-1-naphthaldehyd
Zusammenfassung Die im Titel genannten Komplexe wurden in ethanolischem Medium hergestellt. Sie sind inDMF Nichtelektrolyte und haben laut Elementaranalyse die Zusammensetzung Ligand:Metall=1:1, 2:2 und 1:2. Basierend auf IR-, UV- und EPR-Spektren wird die Koordinationszahl 6 (oktahedrale Geometrie) vorgeschlagen. Es wurden TGA- und DTA-Studien durchgeführt und das elektrochemische Verhalten der Metallkomplexe untersucht.相似文献
84.
M. A. Majeed?Khan M. Wasi?Khan Mansour Alhoshan M. S. AlSalhi A. S. Aldwayyan 《Applied Physics A: Materials Science & Processing》2010,100(1):45-51
Pure and Co-doped ZnO nanostructured samples have been synthesized by a chemical route. We have studied the structural and
optical properties of the samples by using X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), field-emission
transmission electron microscope (FETEM), energy-dispersive X-ray (EDX) analysis and UV–VIS spectroscopy. The XRD patterns
show that all the samples are hexagonal wurtzite structures. Changes in crystallite size due to mechanical activation were
also determined from X-ray measurements. These results were correlated with changes in particle size followed by SEM and TEM.
The average crystallite sizes obtained from XRD were between 20 to 25 nm. The TEM images showed the average particle size
of undoped ZnO nanostructure was about 20 nm whereas the smallest average grain size at 3% Co was about 15 nm. Optical parameters
such as absorption coefficient (α), energy band gap (E
g
), the refractive index (n), and dielectric constants (σ) have been determined using different methods. 相似文献
85.
n-Type indium antimonide-Au hybrid macro-structure was successfully fabricated on p-GaAs substrate by a simple and economic
flash evaporation technique. The elemental composition of the prepared InSb film was confirmed by energy dispersive X-ray
spectroscopy microanalysis (EDX). The surface topography and crystal structure of the InSb film was characterized by scanning
electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The magnetoresistance of the prepared hybrid macro-structure
was measured and discussed in terms of the model of current redistribution. 相似文献
86.
87.
Mansour Hashemi 《代数通讯》2018,46(9):4104-4119
88.
89.
We count derangements, involutions and unimodal elements in the wreath product C
r
≀ S
n
by the numbers of excedances, fixed points and 2-cycles. Properties of the generating functions, including combinatorial
formulas, recurrence relations and real-rootedness are studied. The results obtained specialize to those on the symmetric
group S
n
and on the hyperoctahedral group B
n
when r = 1, 2, respectively. 相似文献
90.