Background: Polymethyl methacrylate (PMMA) is the most commonly used material in denture fabrication. The material is far from ideal in fulfilling the mechanical requirements. Midline fracture; poor thermal conductivity and water sorption, are common problem in this material. The purpose of this study was to evaluate the effect of addition of surface treated Aluminum oxide nano fillers on some properties of heat cured (PMMA). Materials and methods: In addition to controlled group of heat cured PMMA the silanized (Al2O3) nanoparticles was added to PMMA powder by weight in three different percentages 1wt%, 2wt% and 3wt%, mixed by probe ultra-sonication machine. 200 specimens were constructed and divided into 5 groups according to the test (each group consist of 40 specimens) and each group was subdivided into 4 sub-groups. The tests conducted were thermal conductivity, thermal diffusivity, transverse strength, indentation hardness (shore D), surface roughness, water sorption and solubility. The results were statistically analyzed using ANOVA and Dunntt t-test. Results: A highly significant increase in transverse strength was observed with the addition of (Al2O3) nanoparticles to (PMMA) at the percentage of 1wt%, the value was 117.72 Mpa and significant increase at 2wt%; while a significant reduction occurred in transverse strength at the percentage of 3% the value was 90.110 Mpa. A significant increase in surface hardness and non significant differences in surface roughness were observed for all percentages. Conclusion: The addition of Al2O3 nanoparticles to acrylic resin improves the thermal properties and transverse strength of acrylic resin at the same time this addition decreases water sorption and solubility.
Reading roles as the third skill in the range of English as a Foreign Language (EFL) learning. Although the capability of reading in both academic and non-academic texts is assessed on standardized tests, few of oral interpretation of written language excludes images from estimating literary knowledge. This paper highlights strategies of reading comprehension and visual literacy. It aims to investigate either textual or visual reading in EFL can make an impact on students' comprehension. The effective use of visuals changes instructing reading comprehension recently.The imagery-text model can affect developing reading comprehension and enhancing intellectual thinking. The study hypothesizes that there is no relationship between reading and
... Show MoreThis research delves into the role of satirical television programs in shaping the image of Iraqi politicians. The research problem is summarized in the main question: How does satire featured in television programs influence the portrayal of Iraqi politicians? This research adopts a descriptive approach and employs a survey methodology. The primary data collection tool is a questionnaire, complemented by observation and measurement techniques. The study draws upon the framework of cultural cultivation theory as a guiding theoretical foundation. A total of 430 questionnaires were disseminated among respondents who regularly watch satirical programs, selected through a multi-stage random sampling procedure.
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This paper details the process of designing, analysing, manufacturing, and testing an integrated solid-state hydrogen storage system. Analysis is performed to optimise flow distribution and pressure drop through the channels, and experimental investigations compare the effects of profile shape on the overall power output from the fuel cell. The storing of hydrogen is given much attention in the selection of a storage medium, and the effect of a cooling system to reduce the recharging time of the hydrogen storage vessel. The PTFE seal performed excellently, holding pressure over 60 bar, despite requiring changing each time the cell is opened. The assembly of the vessel was simple and straightforward, and there was no indication of pressure
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The research aims to determine the impact of the strategy performance evaluation and of the Standards (leadership, people, knowledge, processes, financial) in the achievement of organizational effectiveness in accordance with the dimensions (planning and setting goals, Exploitation of the Environment, achieve the goals, the ability to adapt, information management and communications) and the relationship between them, the problem of the research in the growing interest in the process of performance evaluation for organizations, the erroneous belief that the performance evaluation activity is useful, and the fact that performance evaluation process is one of the main tasks of the work of the Office of the Inspecto
... Show MoreA collection of pictures of traditional Kurdish women's national clothing and contemporary clothing was collected. A visit was also made to the city of Sulaymaniyah and the city of Halabja to find out the foundations of traditional clothing for the Kurdish regions and the impact of contemporary fashion on traditional dress. Which represents the culture and regionalism and reflects the picturesque nature of northern Iraq, and in order to complete the study, the parametric measurements of the clothes were analyzed and the graphs of the dress and its accessories were re-drawn to understand and make a comparison between them to study the clear influences and changes and examine the possibility of benefiting from them in sewing contemporary f
... Show MoreThe aim of the research is to identify the educational and psychological effects of the positive and negative aspects of using social networking websites. The researcher administered a number of questions to (250) users of different types of social networking websites. He analyzed his research results and obtained a number of results. The research has reached a number of recommendations and suggestion: Regulating the use of social media. Monitoring the parents of the sites used by children in a way that they do not feel they are observers. It is necessary to devote an hour daily to show the importance of real social life for children other than using social media. It is necessary to show the importance of choosing friends who hav
... Show MoreThis research study examines the impact of information technology on firm profitability and stock returns. Using a comprehensive dataset of firms across various industries, this research employs rigorous statistical analysis techniques to investigate the relationship between IT investments, firm profitability metrics, and stock returns. The study focuses at how IT investments affect financial performance measures including return on assets (ROA) and return on equity (ROE), with P-values of 0.34 and 0.12, respectively. Furthermore, the study investigates the influence of IT on stock returns, taking into account market capitalization, industry trends, and macroeconomic variables. This study's conclusions center on the beneficial assoc
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