Fatigue failure is almost considered as the predominant problem affecting automotive parts under dynamic loading condition. Thus, more understanding of crack behavior during fatigue can strongly help in finding the proper mechanism to avoid the final fracture and extent the service life of components. The main goal of this paper is to study the fracture behavior of low carbon steel which is used mostly in automotive industry. For this purpose, the fractography of samples subjected to high and low stress levels in fatigue test then was evaluated and analyzed. Hardness and tensile tests were carried out to determine the properties of used steel. Also, the samples were characterized by microstructure test and XRD analysis to examine the constitute phases. The fatigue test (S-N curve) was done at stress ratio (R= -1), and the fracture examination was perform using Scanning Electron Microscope (SEM). The results of microstructure and XRD analysis were indicating that the Ferrite and a little amount of pearlite are the dominant phases of this steel. Whereas, the fractography observations reveal that the void coalescence ductile fracture is the main failure mode in samples with high stress level, while the ductile fracture (void coalescence) with Transgranular Cleavage fracture was noticed in low stress fatigue mode for this alloy.
The main goal of this in vivo study was to evaluate the effect of 532nm Q-switched Nd: YAG Laser in combination with Human Serum Albumin 20% concentration (as a welding aid) on the liver tissue repair clinically, and histologically. The animals used in this study were 21 male rabbits divided into three main groups: control group (3 rabbits), conventionally treated group (9 rabbits) and Laser treated group (9 rabbits). Each two main groups (conventional and laser treated) consist of three sub-groups depending on the response evaluation at three different periods. The Laser group was treated using 532nm Q-switched Nd: YAG laser after adding human serum albumin immediately on the incised liver’s tissue. The energy of was 460mJ, and 4Hz fr
... Show MoreThis research aims at recognizing the concept of Innovation in offering the banking services as well as the concept and dimensions of competitive advantage . And to identify and analyze the relationship ( correlation and impact ) between the concept of Innovation in offering the banking services and the dimensions of the competitive advantage under discussion . The research includes all Iraqi private banks in Baghdad city only of the (20) banks . The researcher adopted , in this study , a random sample of the distribution of the questionnaire to members of the research sample are managers , customers and employees in these banks , and were distributed ( 115 ) form questionnaire , ( 97 ) form w
... Show MoreFicus (FIC) leaf extract used as corrosion inhibitor for carbon steel alloy (C.S) in two corrosive environments (saline and acidic) with four concentrations (1, 2, 3 and 4 ppm) at varied temperature range between (298-328 K) using electrochemical polarization measurements. The importance of this work focused on the use the green chemistry that is far from the chemical materials effect. The results of polarization presented the FIC inhibitor consider a mixed type (anodic and cathodic) inhibitor. Tafel curve used to evaluate the corrosion inhibition activity. In a saline medium, the best inhibitor efficiency reaches to (87%) in 2 ppm and IE% reach to (99%) for HCl medium inhibited by 1ppm. Langmuir isotherm obeys the study by thermodynamic pa
... Show MoreIn this paper, effective slab width for the composite beams is investigated with special emphasis on the effect of web openings. A three dimensional finite element analysis, by using finite element code ANSYS, is employed to investigate shear lag phenomenon and the resulting effective slab width adopted in the classical T-beam approach. According to case studies and comparison with limitations and rules stipulated by different standards and codes of practice it is found that web openings presence and panel proportion are the most critical factors affecting effective slab width, whereas concrete slab thickness and steel beam depth are less significant. The presence of web opening reduces effective slab width by about 21%.
... Show MoreBackground: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left u
... Show MoreThe aim of the research: To identify the trends of students of the College of Physical Education and Sports Sciences towards modern teaching methods. To determine the type of strategies used that students prefer in practical lessons. In light of the research results, the researcher adopted the descriptive method because it is appropriate for the study. The research community is represented by students of the College of Physical Education and Sports Sciences (fourth stage), amounting to (320) students. Conclusions: The research results indicate that students of the College of Physical Education and Sports Sciences have positive and strong attitudes towards using modern teaching methods, and they realize their reality in improving interaction
... Show MoreThe aim of the research: To identify the trends of students of the College of Physical Education and Sports Sciences towards modern teaching methods. To determine the type of strategies used that students prefer in practical lessons. In light of the research results, the researcher adopted the descriptive method because it is appropriate for the study. The research community is represented by students of the College of Physical Education and Sports Sciences (fourth stage), amounting to (320) students. Conclusions: The research results indicate that students of the College of Physical Education and Sports Sciences have positive and strong attitudes towards using modern teaching methods, and they realize their reality in improving interaction
... Show MoreThe research aims to identify and diagnose the public relations strategies in its digital online communications by the United Nations High Commissioner for Refugees (UNHCR) in managing the crisis of Iraqi refugees in Turkey. A content analysis form was designed for the digital content of the UNHCR's website dedicated to topics and issues concerning Iraqi refugees that were covered by the site, adopting a comprehensive enumeration approach. The study covered the period from 01/03/2022, to 30/06/2022. The research yielded several key findings, including the predominant use of media, advertising, and education strategies in managing the crisis of Iraqi refugees in Turkey. News and reports ranked first among the media
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המשבר הוא מצב מצוי רב בחברת המדינות אחרי המלחמות והשינויים הגדולים במאה העשרים, ומשבר הזהות הוא ממשברי המאה העשרים שזכה בהתעניינות רבה בכל תחומי המדעים האנושיים, ומהם תחום הספרות. ובספרות העברית היה הסופר א. ב. יהושע מהסופרים החשובים שהתעניין בנושא הזהות בישות הציונית, הוא התווכח בנושא ביצירותיו, ראיוניו ורוב הכנסים התרבותיים והפוליטיים שנכח אותם, הוא השתמש באסכולה ספרותית מאו
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