Ferrites with the formula Cu0.5Ti0.5HoxFe2-xO4 (x= 0 and 0.09) were prepared by standard ceramic method. The powder mixtures were presintered at 900 oC for 5h. The final sintering of the pellets was performed at 1100 oC for 2 hrs. The dielectric properties and AC conductivity were measured at different temperatures over the frequency range 100Hz - 10MHz. The variation in dielectric constant with frequency revealed that dispersion is due to the Maxwell–Wagner type of interfacial polarization in accordance with Koop’s phenomenological theory. This ferrite showed high value of dielectric constant. At low frequencies the dielectric constant and dielectric loss factor was found to decrease with the increase in frequency and Ho addition. The dielectric loss decreased with temperature rise. The frequency dependence of dielectric loss tangent is found to be abnormal at various temperatures, the abnormal behavior of dielectric relaxation processes was observed. The prepared ferrite showed low range of AC conductivity. The AC conductivity was noticed to increase with frequency and temperature. While the conductivity decreased with Ho addition.
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The idea of this research is based on presenting a study specialized with the rules and bases of the Iraqi methodological music composition of the Symphony Orchestra according to the construction of the musical compositions of great forms and which are characterized by the melody difference and variation within their musical fabric according to the method of distributing the instruments and their types within the orchestra. The researcher has been interested in studying this building based on what is written for him according to the stringed instruments arc instruments and bass, which is represented by the cello and the contrabass. It is possible through the analysis of the melody structure features of these instruments and the melody re
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The current study was conducted on the southern part of Gharaf River in order to define the physical-chemical properties and the impact of the Tigris River’s floodplain water on its ecological characteristics during 2019. Four sites were selected along the southern part of the river. The findings showed a strong connection between the temperature of air and water at all sites. A value ranging from 4.85 - 84.65 NTU was reported for turbidity. The water was found to be oligohaline, low alkaline, and well ventilated due to high dissolved oxygen concentrations. Gharaf River is considered to be of questionable clean water, according to the results of BOD5. The total a
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The present study included the impact of the follow-up variation in the temperature of aqueous medium in the vertical migration behavior of different groups of Zooplankton, consisted species Cyclops vernalis, Daphnia magna, Diaptomus dilopatus, that have been grown in controlled in terms of light and pH laboratory conditions, so choosing temperature of respectively 16,20,24,28, and 32 ËšC. The result showed a clear change in the migration behavior of testing planktonic species, it was a negative relationship between temperatures arises and individual of D. magna in the water column.While being appositive relationship with individual of C. vernalis and the same with D. dilopatus. Also, the result revealed a different impact
... Show MoreThis research aims to introduce a new technique-off-site and self-form segmental concrete masonry arches fabrication, without the need of construction formwork or centering. The innovative construction method in the current study encompasses two construction materials forms the self-form masonry arches, wedge-shape plain concrete voussoirs, and carbon fiber-reinforced polymer (CFRP) composites. The employment of CFRP fabrics was for two main reasons: bonding the voussoirs and forming the masonry arches. In addition, CFRP proved to be efficient for strengthening the extrados of the arch rings under service loadings. An experimental test was conducted on four sophisticated masonry arch specimens. The research parameters were the Keystone thic
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The determination of aerodynamic coefficients by shell designers is a critical step in the development of any projectile design. Of particular interest is the determination of the aerodynamic coefficients at transonic speeds. It is in this speed regime that the critical aerodynamic behavior occurs and a rapid change in the aerodynamic coefficients is observed. Two-dimensional, transonic, flow field computations over projectiles have been made using Euler equations which were used for solution with no special treatment required. In this work a solution algorithm is based on finite difference MacCormack’s technique for solving mixed subsonic-supersonic flow problem. Details of the asymmetrically located shock waves on the projectiles hav
... Show MoreZinc Oxide is an indispensable substance in the field of dental treatment. It is used daily and intensively in all governmental and private dental clinics, leading to the disposal of very high concentrations of zinc with waste and eventually in landfill sites as a final destination for solid waste removal. This indicates the urgent need to investigate its behavior upon disposal due to the surrounding conditions. Approximately 4195 g of mixed dental waste samples were collected from (17) healthcare centers in Baghdad Al-Karkh. The leaching behavior of ZnO powder was investigated through batch reactors using makeup dental solid waste samples. The ZnO leaching was tested with 3 conditions; acidic, alkaline, and Ionic Streng
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