This work presents the characteristics of plasma produced by fundamental wavelength (1064 nm) Q- switched Nd:YAG laser on Ag:Ni alloy in distilled water were investigated at different laser energies by optical emission spectroscopy technique. The size of produced nanoparticles from Ag:Ni target in distilled water were studied, by x-ray diffraction, UV-visible absorbance and atomic force microscopy, at different laser energies. Spectroscopic measurements show that electron temperature and electron density increase with increasing laser energy. It was found from AFM measurements that the produced nanoparticle size decrease from 97.13 nm to 71.20 nm, while XRD shows that the crestalline size decrease from 15.5 nm to 9 nm with increasing pulse laser energy. UV- visible absorbance shows at plasmon peaks shifted from 410 to 395 nm with increasing laser energy.
BaTiO3 thin films have been deposited on Si (111) and glass substrates by using pulsed laser deposition technique. The films were characterized by using X-ray diffraction, atomic force microscope and optical transmission spectra. The films growth on Si after annealing at 873K showed a polycrystalline nature, and exhibited tetragonal structure, while on glass substrate no growth was noticed at that temperature. UV-VIS transmittance measurements showed that the films are highly transparent in the visible wavelength region and near-infrared region for sample annealing on glass substrate. The optical gap of the film were calculated from the curve of absorption coefficient (αhν) 2 vs. hν and was found tobe 3.6 eV at substrate temperature 5
... Show MoreThe modified Hummers method was applied to prepare graphene oxide (GO) from the graphite powder. Tin oxide nanoparticles with different loading (10-20 wt.%) supported on reduced graphene oxide were synthesized to evaluate the oxidative desulfurization efficiency. The catalyst was synthesized by the incipient wetness impregnation (IWI) technique. Different analysis methods like FT-IR, XRD, FESEM, AFM, and Brunauer-Emmett-Teller (BET) were utilized to characterize graphene oxide and catalysts. The XRD analysis showed that the average crystal size of graphene oxide was 6.05 nm. In addition, the FESEM results showed high metal oxide dispersions on the rGO. The EDX analysis shows the weight ratio of Sn is close to its theoretical weight.
... Show MoreThe effects of reinforcing polymers with glass and graphite particles on enhancing their flexural properties are investigated. Five composites were fabricated using the same polymer matrix material with different volume fractions of reinforcement particles. They comprise glass particles and graphite particles each having volume fractions of 20% and 30% as well as a hybrid composite having 10% glass and 10% graphite. Three-point bending tests using a Universal Testing Machine were carried out on specimens of the above mentioned composites, as well as specimens of the polymer matrix material to determine their flexural properties. The experimental test results indicate that the flexural stiffness of all the composites wer
... Show MoreIn this study, a review of variety of processes that are used in the treatment produced water prior to reuse or to responsible disposal are presented with their environmental issues and economical benefits. Samples of produced water from five locations in Rumaila oilfield/in south of Iraq were taken and analyzed for their contents of brine, some heavy metals, total suspended solids and oil and grease. Moreover, two samples of water were treated using reverse osmosis technique which showed its ability to treat such contaminated water. The results showed that the environmental impact of produced water arises from its chemical composition; i.e., its salt content, its heavy metals, and hydrocarbon contents.
The 3D electro-Fenton technique is, due to its high efficiency, one of the technologies suggested to eliminate organic pollutants in wastewater. The type of particle electrode used in the 3D electro-Fenton process is one of the most crucial variables because of its effect on the formation of reactive species and the source of iron ions. The electrolytic cell in the current study consisted of graphite as an anode, carbon fiber (CF) modified with graphene as a cathode, and iron foam particles as a third electrode. A response surface methodology (RSM) approach was used to optimize the 3D electro-Fenton process. The RSM results revealed that the quadratic model has a high R2 of 99.05 %. At 4 g L-1 iron foam particles, time of 5 h, and
... Show MoreThe study focused on the treatment of real oilfield produced water from the East Baghdad field affiliated to the Midland Oil Company (Iraq) using an oil skimming process followed by a coagulation/flocculation process for zero liquid discharge system applications. Belt type oil skimmer was utilized for evaluating the process efficiency with various operating conditions such as temperature (17-40 °C) and time (0.5-2.5 hr.). Polyaluminum chloride (PAC) coagulant and polyacrylamide (PAM) flocculant was used to investigate the performance of the coagulation/flocculation process with PAC dosage (5-90 ppm) and pH (5-10) as operating conditions. In the skimming process, the oil content, COD, turbidity, and TSS decreased with an increase in tempera
... Show MoreEnglish is spoken by its native speakers in two different forms. Reduced form which marks the colloquial and rapid speech so that it is easily produced and a citation or unreduced form which is a characteristic of careful, emphasized and slow speech.
This paper investigates Iraqi EFL university students’ production of the two forms mentioned above. The sample chosen includes twenty fourth year students, of which ten are males and the other ten are females from the Department of English of the College of Languages of the University of Duhok in Kurdistan Region of Iraq in the academic year 2020-2021. The material tested is six connective words which represent the commonest ones in every-day co
... Show MoreThe goal of this work is to study plasma parameters for Fe plasma generated by exploding wire (EEW) in carbon nanotubes-water colloid with three current values (50, 100 and 150)A. In this research, the plasma electron temperature (Te), the electron density (ne), electron density (ne), plasma frequency(f p), Debye length (λD) and Debye number (ND) were found for Fe produced by Arc discharge plasma. Boltzmann plot was used to calculate the plasma electron temperature (Te);electron density (ne) was calculated from Stark broadening. It was found that the electron temperature values increased from (0.4
... Show More