In this research, damping properties for composite materials were evaluated using logarithmic decrement method to study the effect of reinforcements on the damping ratio of the epoxy matrix. Three stages of composites were prepared in this research. The first stage included preparing binary blends of epoxy (EP) and different weight percentages of polysulfide rubber (PSR) (0%, 2.5%, 5%, 7.5% and 10%). It was found that the weight percentage 5% of polysulfide was the best percentage, which gives the best mechanical properties for the blend matrix. The advantage of this blend matrix is that; it mediates between the brittle properties of epoxy and the flexible properties of a blend matrix with the highest percentage of PSR. The second stage included reinforcing the best blend matrix of epoxy-polysulfide (the blend matrix with the best percentage of polysulfide resulted from the previous stage), by different volume percentages of short fibers (Carbon& Glass) separately and randomly. The volume percentages of fibers were (2.5%, 5%, 7.5%, and 10%). The third stage included reinforcing the blend composites with highest percentages of carbon and glass fiber, by different weight percentages of nano-particles (Red mud& Fly ash) separately. The weight percentages of particles were (0.5%, 1%, 1.5%, and 2%). The experimental results showed that blending polysulfide rubber with epoxy increased the damping ratio. As for reinforcement materials, they decreased the damping ratio, where glass fiber composites have significantly higher damping ratio than other composites.
This research discusses one of the most important means of reducing corruption in public sector companies and government departments, a relationship of cooperation and coordination between the external auditor and internal auditor, in the light of ISA (610), the recommendations of the International Organization of Supreme Audit Institutions (INTOSAI) and the National Strategy to combat corruption. The research was based on two assumptions: the first was weak relationship of cooperation and coordination between the external auditor and internal auditor leads to weakne
... Show MoreThe aim of this research is to identify the impact of the effectiveness of digital transformation technology in improving the efficiency of the insurance service in the public insurance companies in Iraq through digital transformation technology in the insurance process "promotion of the insurance product, submission of insurance application, underwriting, settlement of losses" and to achieve this goal a questionnaire was designed A survey distributed in the surveyed community Which represents the decision makers in the researched companies under study, and one of the most important results of the research was the existence of a relationship between digital transformation and improving the efficiency of the insurance process, whether thr
... Show MoreResearchers classified deconstruction as a strategy concerned with reading the philosophical, literary, artistic and critical texts according to (construction and deconstruction) binarism, which is an applied procedural space that calls for researching the layers of meaning and its non-closure. It establishes reversals in the text level. The center changes into a margin and vice versa. Thus the two researchers sought to study the deconstruction strategy and its work in the theatre field, that deconstruction is considered one of the most important modern currents that actively inters in reading the theatre show. The research studies the procedure of the construction and deconstruction of the Iraqi theatre actor reg
... Show MoreSome types of the fungus Aspergillus were isolated from some hospitals in the city of Baghdad (Imam Ali Hospital and Sadr General Hospital). The samples were taken by Transport media at a rate of three replicates of each place isolated from samples from different places within the hospital (waste, baths, the sick beds, corridors and room floors) for the purpose of isolating and diagnosing the fungus on the Czapeck Dox Agar media. It was noticed that the spread rate of fungus Aspergillus was 70% compared to other species that have emerged during the isolation process of the Sabouraud's Dextrose Agar media. The species A.niger (56.25%) was considered the most common type of fungus visible during the isolation process of the Imam Ali Hospit
... Show MoreIn this study, Zizphus spina-christi leaf powder was applied for the adsorption of methyl orange. The effect of different operating parameters on the Batch Process adsorption was investigated such as solution pH (2-12), effect of contact time (0-60 min.), initial dye concentration (2-20 mg/L), effect of adsorbent dosage (0-4.5 g) and effect of temperature (20-50ᵒC). The results show a maximum removal rate and adsorption capacity (%R= 23.146, qe = 2.778 mg/g) at pH = 2 and equilibrium was reached at 40 min. The pseudo- second-order kinetics were found to be best fit for the removal process (R2 = 0.997). Different isotherm models (Langmuir, Freundlich, Dubini-Radushkevich,Temkin) were applied in this stud
... Show MoreThe study aims to demonstrate the importance of instructional methods in teaching Arabic language as a second language or teaching the Arabic language to non-native speakers. The study is in line with the tremendous development in the field of knowledge, especially in the field of technology and communication, and the emergence of many electronic media in education in general and language teaching in particular. It employs an image in teaching vocabulary and presenting the experience of the Arabic Language Institute for Non-Speakers-King Abdul-Aziz University. The study follows the descriptive approach to solve the problem represented by the lack of interest in the educational methods when teaching Arabic as a second language. Accordingl
... Show MoreAsthma is a chronic respiratory disease highly prevalent worldwide. Recent studies have suggested a role for microbiome-associated gut–lung axis in asthma development. In the current study, we investigated if Resveratrol (RES), a plant-based polyphenol, can attenuate ovalbumin (OVA)-induced murine allergic asthma, and if so, the role of microbiome in the gut–lung axis in this process. We found that RES attenuated allergic asthma with significant improvements in pulmonary functions in OVA-exposed mice when tested using plethysmography for frequency (F), mean volume (MV), specific airway resistance (sRaw), and delay time(dT). RES treatment also suppressed inflammatory cytokines in the lungs. RES modulated lung microbiota and cause
... Show MoreBackground: This study aimed to compare the mechanical properties between four groups of newly fabricated combination wires according to their method of union, according to the gauges of wires and a comparison were made between them and their originals. Materials and method: A total of 60 stainless steel combination wires were fabricated , divided into four groups according to gauge of wires and their method of union, each of them with 15 samples, the groups were welded (0.016x0.022-0.016 and 0.016x0.022-0.018) and soldered (0.016x0.022-0.016 and 0.016x0.022-0.018), samples were made according to certain parameters which were : for the welded samples: length,weight, duration of pulsation and size of copper electrode tips used; for the sold
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