Lithium–Manganese ferrites having the chemical formula (Li0.5-0.5x Mnx Fe2.5-0.5x O4), (0 ≤ x ≤ 1) were prepared by double sintering powder processing. The density of the ferrite increased with Mn content while the porosity was noticed to decrease. The dielectric constant was found to increase at high frequencies more rapidly than the low ones. The dielectric constant found to decrease with Mn content. The decrease in loss factor with frequency agreed with Deby’s type relaxation process. A maximum of dielectric loss factor was observed when the hopping frequency is equal to the external electric field frequency. Manganese substitution reduced the dielectric loss in ferrite. The variation of tanδ with frequency shows a similar nature to that of ε’’ with frequency. The resistivity found to decrease with frequency, and this behavior with frequency was discussed according to Koop’s theorem. Maximum resistivity was obtained at x = 0.8 doping level of Mn.
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In this search, we examined the factorial experiments and the study of the significance of the main effects, the interaction of the factors and their simple effects by the F test (ANOVA) for analyze the data of the factorial experience. It is also known that the analysis of variance requires several assumptions to achieve them, Therefore, in case of violation of one of these conditions we conduct a transform to the data in order to match or achieve the conditions of analysis of variance, but it was noted that these transfers do not produce accurate results, so we resort to tests or non-parametric methods that work as a solution or alternative to the parametric tests , these method
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The tensions and crises and the psychological pressure as well as the rapid changes and great development which is taking place in the present time. And witnessing community of wars and conflicts that give rise to future concern among members of the community in general and students in particular, as it included the current research a number of chapters, the First chapter contains the research problem, the important goal, then set researcher terminology that has defined and contained in the title of research in the form (concern the future, artistic expression, middle school). The Second chapter included three sections, the first included the nature of adolescence and traits, characteristics and pr
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The techniques of contemporary Iraqi painting and their reflection on the productions of students of art education is an important subject in the field of painting at the theoretical and practical levels in academic study, whether theoretical or practical. Al-Iraqi is one of the arts with historical roots and a distinguished position among other artistic genres. Painting has received a sufficient level of development through the use of various contemporary techniques to advance it for the better.
The methodological framework included the problem of research and the need for it, and then the importance of research came in shedding light on the techniques of contemporary Iraqi painting, and the impact of these techniques on the producti
The purpose of this research is to highlight the relationship between the administrative investigation and the improvement of institutional performance, and the research sought to achieve a set of cognitive and applied goals. the administrative investigation is the modern trend of managing the offices of the general hginspectors and the main source to build the necessary standards to manage and invest its resources efficiently and effectively required to achieve the goals it seeks. The institutional performance is the cornerstone for the implementation of all tasks and duties carried out by institutions operating within the borders of a particular country, The significant change
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Benign prostatic hyperplasia (BPH) is one of the most common disease and major cause of morbidity in elderly men which may lead to bladder outflow obstruction and lower urinary tract symptoms (LUTS). Although sex steroid hormones play fundamental roles in prostate growth, their clinical significance is not completely clear. In the present study we assessed whether serum hormones levels as markers of prostate disease. This study includes (40) patients with benign prostatic hypertrophy and (40) control group with age rang (41-79) and (42-71) years respectively. The following biochemical investigations have been studied: Testosterone, Estradiol (E2), and Prostatic Specific Antigen (PSA) levels using ELISA method which correlated with t
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Cholinesterases are among the most efficient enzymes known. They are divided into two groups: acetylcholinesterase (AChE) involved in the hydrolysis of the neurotransimitter acetylcholine, and butyrylcholinesterase (BChE) of unknown function. Several crystal structures of the former have shown that the active site is located at the bottom of a deep and narrow gorge. Human BChE has attracted attention because it can hydrolyze toxic esters and nerve agents. Here we analyze the complexes of cholinesterase with soman by describing the 3D geometry of the complex, the active site, the changes happened through the inhibition and provide a description for the mechanism of inhibition. Soman undergoes degradation in the active site of the AChE and BC
... Show MoreThis research is one of the public research aimed at identifying the communication habits and the implications of the content on the communication process, especially as the audience of specialized media is often characterized by effectiveness, depth and active in tracking the media message and interaction with its content. It means such audience is a positive, very active, dynamic, and very alert audience driven by his interests and psychological needs to watch specific programs meet his desires.
This satisfaction can only be achieved through the use of specialized media capable of producing programs that will communicate and interact between the ideas you present and this audience.
The phenomenon of specialized satellit
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