Nanoferrite materials have been synthesized by sol-gel auto combustion method. The effect of doping different percentages of Y2O3 (0.34 µm) on the physical and mechanical properties of selected mixed ferrite [(Li2.5Fe0.5) 0.9(Co4Fe2O4) 0.1] by adding 10% Cobalt ferrite was studied. Physical properties (i.e. .density, porosity and water absorption) were affected by the doping, where the density increased about 32% at 6 wt% Y2O3, while porosity has a drastically decreased about 80% at 6% Y2O3 and has a correlation effect on the mechanical properties(Splitting tensile strength and Vickers microhardnss). The fracture strength at 1 % wt. of Y2O3 has doubled value of the undoped sample and then decreased. The same behavior shows with the testing of Vickers micro hardness.SEM ( Scanning electron microscopy ) micrographs revealed that the microstructure of the fracture surface of the samples consist of detached approximately closely packed particles and also showed the formation of micro agglomerated particles with some voids . By doping with Y2O3 the pores decreased and a dense material obtained
Modified unsaturated polyester (MUPE) was blended with Cellulose (Cls) and with ethyl cellulose (ECls) at ambient conditions in the presence of ethyl methyl ketone peroxide (EMKP) as hardener. The blends containing different weight percentages (5-25 %) of Cls or ECls. Mechanical properties (impact strength, hardness, and bending) and dielectric constant were determined. The results observed that Cls increases the impact strength, hardness, and dielectric constant and decreases the bending of the MUPS, while ECls causes an increase in the three mechanical behaviours and a decrease in the dielectric constant of the MU-PS.
Background: Oral lichen planus (OLP) is a relatively common chronic inflammatory muco-cutaneous disease classified among the potentially malignant lesions of oral mucosa. The aim of this study is to investigate and compare the expression of p53 and PCNA proteins in oral lichen planus and epithelial dysplasia cases. Materials and methods:Formalin-fixed and paraffin- embedded blocks of 21 lichen planusand 21 oral dysplasia cases were referred to immunohistochemical (IHC) analysis for anti p53 and anti PCNA monoclonal antibodies. Results: The results showed that positive nuclear staining for p53 was found in 11/21 (52.4%) cases of lichen planus and 17/21 (80.9%) cases of dysplasia. Positivity for PCNA was observed in 18/21(85.7%) of oral li
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The ejector refrigeration system is a desirable choice to reduce energy consumption. A Computational Fluid Dynamics CFD simulation using the ANSYS package was performed to investigate the flow inside the ejector and determine the performance of a small-scale steam ejector. The experimental results showed that at the nozzle throat diameter of 2.6 mm and the evaporator temperature of 10oC, increasing boiler temperature from 110oC to 140oC decreases the entrainment ratio by 66.25%. At the boiler temperature of 120oC, increasing the evaporator temperature from 7.5 to 15 oC increases the entrainment ratio by 65.57%. While at the boiler temperature of 120oC and
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The bank risks has greaten and changed in its nature under the developments of financial liberalization, banking innovation and increasing use for new financial instruments which created by the huge technological advancement happened in the banking industry. So that, banks in large choose to base the profitability measures adjusted for risks; that is we introduced this research. The most important reason led us to do this is the restriction to use the modern statistical methods by trade bank in Arab countries equally with world banks which were the antecedent to base those models. Therefore, the research problem is embedded in the banks need to use measures that link between profitability and risks and this is what achieved by RARC
... Show MoreThe subject of disclosure, transparency and corporate governance taking globally significant attention recently, especially after the collapse of many large companies because the level of disclosure and transparency is an important measure of the effectiveness and reliability of the system of governance in the companies, the equity in the provision of correct information and clear and complete in a timely manner to all stakeholders in the life of the company with whom in relation strengthen the confidence the company's management systems and automatic guide the staff and the decision-making.
The research aims to shed light on the concept of corporate governance, and the reasons and motives of the spread
The aim of this study was to making an analytical study in some kinematics variables in (200) meter breaststroke swimming to first ranking in championship 2003 – Spanish. The swimming in our country still suffering from several obstruction with retarded it’s development for the better since the investigators observe the insufficiency of swimming in our country to any analytical study for the international champions, this led to no specific and scientific discovering to these advanced levels as the estimation of the value of performance from the Iraqi coaches dependent on personality observation dependent on their opinion without referring to the specific and scientific diction. The investigators dependent on several kinematics variables
... Show MoreThis research is an attempt to study and evaluate the maintenance function at Factory 7 - The State General Company for Leather Industries, and to design a computerized preventive maintenance system to design and to analyze preventive maintenance. To accomplish the objectives of this research, data were gathered and analyzed according to the reliability engineering criteria for the period 2/1– 30/6/2005, then a preventive maintenance plan was designed for each machine of the sample study using the computerized system designed in this research. A Monte Carlo Simulation methodology was used for the purpose of evaluating the performance of the preventive maintenance plan of each machine for one year. The simulation res
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ــد ً الوزيرالـــوزيــرمحمد بن علي بن خلف ابو غالب الملقب بـ (فـــخـر الــمـلك )(407هـ-1016م)من الشخصيات المهمة،ية البويهية ، المثيراء الامارواعظم وزرالجدل ، وهذا ما سنوضحهفي البحث .ي كون والده ِ كان صيرفيا ً فلادة ونشأة الوزير فخر الملك في بيئة عنيت بالجانب الأدارأسهمت وٌي ديوان مدينة واسط ، أثرِاتهفي صقل قدرالإالع ِ دارية ، فضلا ً عن صفاتهقلية ،ة البويهية علىاء الأماروالشخصية التي جعلته ُ يكون رمز وزرلكل ةارال
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