The influence of the reaction gas composition during the DC magnetron sputtering process on the structural, chemical and optical properties of Ce-oxide thin films was investigated. X-ray diffraction (XRD) studies confirmed that all thin films exhibited a polycrystalline character with cubic fluorite structure for cerium dioxide. X-ray photoelectron spectroscopy (XPS) analyses revealed that cerium is present in two oxidation states, namely as CeO2 and Ce2O3, at the surface of the films prepared at oxygen/argon flow ratios between 0% and 7%, whereas the films are completely oxidized into CeO2 as the aforementioned ratio increases beyond 14%. Various optical parameters for the thin films (including an optical band gap in the range of 2.25–3.1 eV) were derived from the UV–Vis reflectance. A significant change in the band gap was observed as oxygen/argon flow ratio was raised from 7% to 14% and this finding is consistent with the high-resolution XPS analysis of Ce 3d that reports a mixture of Ce2O3 and CeO2 in the films. Density functional theory (DFT+U) implemented in the Cambridge Serial Total Energy Package (CASTEP) was carried out to simulate the optical constants of CeO2 clusters at ground state. The computed electronic density of states (DOSs) of the optimized unit cell of CeO2 yields a band gap that agrees well with the experimentally measured optical band gap. The simulated and measured absorption coefficient (α) exhibited a similar trend and, to some extent, have similar values in the wavelength range from 100 to 2500 nm. The combined results of this study demonstrate good correlation between the theoretical and experimental findings.
The ground state proton, neutron and matter densities of exotic 11Be and 15C nuclei are studied by means of the TFSM and BCM. In TFSM, the calculations are based on using different model spaces for the core and the valence (halo) neutron. Besides single particle harmonic oscillator wave functions are employed with two different size parameters Bc and Bv. In BCM, the halo nucleus is considered as a composite projectile consisting of core and valence clusters bounded in a state of relative motion. The internal densities of the clusters are described by single particle Gaussian wave functions.
Elastic electron scattering proton f
... Show MoreA simulated ion/electron optical transport and focusing system has been put forward to
be mounted on high voltage transmission electron microscope for in situ investigations.
The suggested system consists of three axially symmetric electrostatic lenses namely an
einzel lens, an accelerating immersion lens, and a decelerating immersion lens, in addition
to an electrostatic quadrupole doublet lens placed on the image side. The electrodes
profile of these lenses is determined from the proposed axial field distributions. The
optical properties of the whole system have been computed together with the trajectory of
the accelerated charged-particles beam along the optical axis of the system. The computed
dimensions of th
Green synthesis is depending on preparation of nano composited SiO2/V2O5 by using the modified sol-gel method depending on rice husk ash as a source for the extraction of silica gel and the product powder of nano composited SiO2/V2O5 characterization by many techniques such as X-ray diffraction spectroscopy (XRD), field emission scanning electron microscopy (FESEM), and N2 adsorptions/desorption isotherms (BET). This study also includs the biological effectiveness of SiO2/V2O5 and its effect on inhibiting bacterial growth after the prepared nanomaterial was applied to wound dressings, which gave a promising result for its use as
... Show MoreIn this work, the effect of aluminum (Al) dust particles on the DC discharge plasma properties in argon was investigated. A magnetron is placed behind the cathode at different pressures and with varying amounts of Al. The plasma temperature (Te) and density (ne) were calculated using the Boltzmann equation and Stark broadening phenomena, which are considered the most important plasma variables through which the other plasma parameters were calculated. The measurements showed that the emission intensity decreases with increasing pressure from 0.06 to 0.4 Torr, and it slightly decreases with the addition of the NPs. The calculations showed that the ne increased and Te decreased with pressure. Both Te and ne were reduced by increasing
... Show MoreTwo field experiments were conducted during the spring season 2020 in Karbala governorate to study the effect of irrigation systems, irrigation intervals, biofertilizers and polymers on some characteristics of vegetative growth and potato production. The results showed that there were significant differences in the values of the average plant height due to the effect of the double interference between the irrigation system and the improvers, The height of potato plant under any irrigation system was superior when adding conditioners compared to the control treatment, as it reached 48.56, 58.00 and 64.33cm when adding polymer, biofertilizer, and polymers+ biofertilizers, respectively compared with the control treatment of 44.64cm in the surf
... Show MoreThe new of compounds synthesized by sequence reactions starting from a reaction of 3-phenylenediamine or 4-phenylenediamine with chloroacetyl chloride to produce the compounds [I]a,b, then the compounds[I]a,b reacted with sodium azide to yield compounds[II]a,b that reacted 1,3-dipolarcycloaddition reaction with acrylic acid to give compounds [III]a,b these compounds reacted with methanol led to ester compounds[IV]a,b then reacted with hydrazine to give acid hydrazide [V]a,b . Finally compounds [V]a,b reacted with aromatic aldehydes to product shiff bases derivatives. The compounds characterized by mp. , IR, 1HNMR in addition to mass spectroscopy for some of them the liquid crystals properties were studied by using polarized optical microsco
... Show MoreBiodiesel can be prepared from various types of vegetable oils or animal fats with the aid of a catalyst.
Calcium oxide (CaO) is one of the prospective heterogeneous catalysts for biodiesel synthesis. Modification
of CaO by impregnation on silica (SiO2) can improve the performance of CaO as catalyst. Egg shells and rice
husks as biomass waste can be used as raw materials for the preparation of the silica modified CaO catalyst.
The present study was directed to synthesize and characterize CaO impregnated SiO2 catalyst from biomass
waste and apply it as catalyst in biodiesel synthesis. The catalyst was synthesized by wet impregnation
method and characterized by x-ray diffraction, x-ray fluorescence, nitr
The Mesopotamian soil is muddy and fertile, and so from ancient eras Iraqis used mud in their building, settlements and architecture in different methodologies according to the nature and the function of the building that was either in its pure form or by mixing it with other materials such as straw . also as raw bricks in different ways either for the whale building or parts of it, or for the finishing parts such as roofing for instance. In this research these different forms and methodologies will permeate through out a chosen examples of historical building, rural buildings and settlements and ancient buildings as well as some current uses of mud in the structures and building in standing cities, this in order to conclude some
... Show MoreIn this study NiO - CoO bimetallic catalysts are prepared with two Ni/Co ratios (70:30 and 80: 20) using the precipitation method of nitrate salts. The effects of Ni /Co ratio and preparation methods on the catalyst are analyzed by using different characterization techniques, i.e. atomic absorption (AA) , XRD, surface area and pore volume measurements according to the BET method . The results indicate that the best catalyst is the one containing the percentage of Ni :Co ( 70 : 30 ). Experiments indicate that the optimal conditions to prepare catalyst are stirring for three hours at a temperature of 60oC of the preparation , pH= (8-9) , calcination temperature at 400oC for two hours
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