The products of composites material are very sesetive to many variables, such as manufacturing process, additive materials, …. etc. Filler or additive plays a major role to determine the formation of the properties and behavior of the composites. In this study, polyethylene terephthalate-based compounds were produced and characterized. The work is concerned to prepare samples of Polyethylene terephthalate (PET) - zinc-ferrite (ZnFe2O4) with different addition ratio as zinc-ferrite (1, 2, 5, 10, 15 and 20) wt% obtained from mixing the solution with a hot pressing method applied under optimum conditions. The densities of the composites for all samples were calculated. Through the work the diffusion of zinc-ferrite into the grain of Polyethylene terephthalate has been noted. Structural properties are studied by using X-ray powder pattern, the results of the XRD diffraction analysis showed that the structure for pure PET has four broad peaks at the (2θ=16.46°,17.45°, 22.72°,25.98°). The non-crystalline behavior of the polymer and the ceramic compound indicates the presence of a crystalline phase with a single cubic structure with a space group fd-3m (227)) (a=b=c=8.44 Å, V=601.45 (Å)³). While adding zinc-ferrite to PET in different concentrations to obtain (PET / ZnFe2O4) composites material will increase the intensity of the X-ray peaks, and change the location of the peaks with the addition of zinc-ferrite. It is noted that X-ray diffraction patterns for PET / ZnFe2O4 (20%) indicates that there was no apparent variation of the patterns of pure Zn-ferrite ceramic diffraction which showed that the crystalline structure remains stable in PET / ZnFe2O4. In addition, the electrical properties of the compounds represented by the dielectric constant (real and imaginary), dielectric loss ( tanδ) and the A.C conductivity as a function of a range of frequencies (50Hz-1MHz) have been measured. The results indicated that these properties increase with increasing concentrations of ceramic addition. On the other hand, these properties decrease with increasing frequency due to the change in polarization mechanisms. It has been proven that these prepared superposed materials possess good stability properties in a wide range of frequencies, making these polymeric overlays of wide use in many applications. As for the measurements of Shore D hardness, it has been shown that the hardness of the compounds increases with increasing ceramic concentrations.
Abstract
The current research aims to examine the effect of the Adi and Shayer model on the achievement of fifth-grade students and their attitudes toward history. To achieve the research objective, the researcher has adopted two null hypotheses. 1) there is no statistically significant difference at the level of (0.05) between the average score of students of the experimental group who study the history of Europe and modern American history according to the model of Addie and Shayer, and the average scores of the students of the control group who study the same subjects according to the traditional method in the test of post-achievement. 2) There was no statistically significant difference at the level (
... Show MoreLead-free 0.88(Na0.5Bi0.5)TiO3–0.084(K0.5Bi0.5)TiO3–0.036BaTiO3 (BNT–BKT–BT) piezoelectric ceramics were prepared using the conventional mixed-oxide method with a sintering temperature range of 1120–1200 °C. The effect of the sintering temperature on the crystal structure, microstructure, and densification, as well as the dielectrics, piezoelectrics, and the pyroelectric properties of BNT–BKT–BT ceramics were investigated. Scanning electron microscopy and X-ray diffraction were used to study the microstructures of the sintered samples. The results showed that the increase in sintering temperature was very effective in improving both the density and electrical properties. However, the samples deteriorated when the sintering te
... Show MoreThis research aims to study the optical characteristics of semiconductor quantum dots (QDs) composed of CdTe and CdTe/CdSe core-shell structures. It utilizes the refluxed method to synthesize these nanoscale particles and aims to comprehend the growth process by monitoring their optical properties over varied periods of time and pH 12. Specifically, the optical evolution of these QDs is evaluated using photoluminescence (PL) and ultraviolet (UV) spectroscopy. For CdTe QDs, a consistent absorbance and peak intensity increase were observed across the spectrum over time. Conversely, CdTe/CdSe QDs displayed distinctive absorbance and peak intensity variations. These disparities might stem from irregularities in forming selenium (Se) layers a
... Show MoreIbn al-Anbari, however, turned to Abu Hatim al-Sijistani in eleven places of his book ((clarify the endowment and start)). The study showed that the right and right was with the son of Anbari and that what went to Sistani saying uniqueness, and contrary to the vast majority of scientists. The study also showed that the science of grammar affects the endowment and initiation, as the study showed that the science of endowment and initiation is one of the important sciences of the Koran, which must be carefully received, researchers.
The purpose of this research is to demonstrate the impact of banking compliance in combating money laundering and terrorist financing through banks. The phenomenon of money laundering and terrorist financing has received wide attention in the countries of the world and international organizations because of the negative effects this phenomenon has on the global economy as a result of exploiting developments and modern banking operations to pass Money laundering and terrorist financing operations in order to legitimize illegal funds and obliterate their criminal sources, which obliged the banking sector to increase control measures in order to reduce these operations, which conceal money laundering thr
... Show MoreWhen the digital technologies entered the world of cinema production, they boosted the ability of the cinematographic medium to implement various subjects with great accuracy, as the development included all the joints and stages of the cinematic film production whether it is a feature film or an animation. Therefore, the process of film manufacturing by the digital technologies reflects the spirit of the age and the development that humanity has attained. What motivated the researcher to determine the topic of the research, which combines between the sound effects and the animated films under the title (aesthetics of employing digital sound effects in animated films), is the work of the digital technologies. The researcher divide
... Show MoreThis study was carried out to evaluate the antioxidant activity of Iraqi sumac seeds (Rhus coriaria. L) (Anacardiaceae). Total phenolic compounds and flavoniods were determined in three different sumac seed extracts (SSE) (aqueous,ethanolic and methanolic extract). For extraction Antioxidant activity of SSE were evaluated by various antioxidant assays, including total antioxidant capacity, reducing power,by using 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging, nitric oxide scavenging, Hydroxyl radical scavenging, and metal ion chelating activities. These various antioxidant activities were compared with ascorbic acid as a standard antioxidant.The results showed that the three(SSE), contained large amounts of phenolic and flavonio
... Show MoreBackground: Quality of life in brain tumor patients is an emerging issue and has prompted neurosurgeons to recon¬sider the need for cognitive assessment in the course of treatment. To date there has been a lack of comprehensive neuropsychological assessment performed preoperatively and in the acute postoperative period in our hospitals.Objectives: to establish the effects of tumors and their surgical treatment, from a neuropsychological perspective, on cognitive functioning in patients with cerebral Gliomas. Methods: This is a prospective study conducted in the Neurosurgical Hospital in Baghdad, Iraq, during the period from January 1999 to January 2001. Any patient admitted during the period of the study with clinical history, signs, sy
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The study aims to identify the extent to which the applied colleges at the University of Technology and Applied Sciences meet the comprehensive quality standards in light of the national education strategy for the 2040 Vision in the Sultanate of Oman. To do this, the researchers used the descriptive approach. They used a questionnaire as a tool for data collection that was applied to (237) administrators, academics, and support functions. The study found that the extent to which the applied colleges at the University of Technology and Applied Sciences meet the comprehensive quality standards in the light of the National Education Strategy 2040 in the Sultanate of Oman recorded a high range. The study als
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The current research is attempt to test the reflection of the lean management on the human resources management practices of two of the most important communication companies operating in Iraq (`Zain & Asia cell), The research aims to Determine the extent of adoption of the lean management approach in the two researched companies, as it improving human resource management practices. The research problem represented in the existence of lack of in some aspects of the application the lean management approach in service sector and neglecting the impact of its tools on the human resource management practices. For this purpose three principle research hypotheses has been formulated, first there is a correlation rel
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