In this work, functionally graded materials were synthesized by centrifugal technique at different
volume fractions 0.5, 1, 1.5, and 2% Vf with a rotation speed of 1200 rpm and a constant rotation time, T
= 6 min . The mechanical properties were characterized to study the graded and non-graded nanocomposites
and the pure epoxy material. The mechanical tests showed that graded and non-graded added alumina
(Al2O3) nanoparticles enhanced the effect more than pure epoxy. The maximum difference in impact strength
occurred at (FGM), which was loaded from the rich side of the nano-alumina where the maximum value was
at 1% Vf by 133.33% of the sample epoxy side. The flexural strength and Young modulus of the functionally
graded samples were enhanced by 43.69% and 52.74%, respectively, if loaded from the alumina-rich side.
On the other hand, when loading (FGM) from the epoxy side, the amount of decrease in bending resistance
was 122.4% while the improvement in bending modulus was 81.11% compared to pure epoxy. Scanning
electron microscopy (SEM) revealed the fracture surface of the impact samples and the gradient scattering of
nanoparticles in the epoxy matrix. Numerous applications can be used to manufacture the functionally
graded material by centrifugal casting method, including for the manufacture of gears and all bending
applications such as leaf springs.
اصبح لمجالس الادارة في الشركات دوراً حاسماً في تعزيز الحوكمة الفاعلة، كونها تتحمل المسؤولية النهائية عن نظم الرقابة الداخلية في شركاتها، ويلعب التدقيق الداخلي دوراً اساسياً في مساعدة تلك المجالس على القيام بمهمات الحوكمة. ولهذا يبذل مجمع المدققين الداخليين الامريكي جهداً كبيراً في توجيه اعضاءه ليكونوا متخصصين في اصول حوكمة الشركات وتحسين وتقوية اخلاقيات العمل وسلامة المنظمة.
لذا فإن ا
... Show Moreأهمية البحث والحاجة إليه :
يعد نسيان المثيرات المعلوماتية التي يتعلمها أو يطلع عليها الفرد في حياته من المشكلات التي يعاني منها الأفراد في جميع مناحي الحياة وليس في مجال الدراسة الأكاديمية فحسب. وبالتالي فان هناك حاجة ملحة ومهمة لابتداع طرائق ووسائل وإمكانيات يمكن عن طريقها التقليل من نسيان المثيرات المعلوماتية المختلفة التي يتعلمها الفرد في حياته اليومية.
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Stop and stop Alsergsti classed many of the characteristics of great poets and
literary arts and persuasions, in Mqamth cash cash Antzmtha three criteria: the
standard of Islam and the standard time, and Maaartadd purposes of poetry. This
has had its effect on lighting stand many of the goals of the poets and their
attitudes.
The first criterion: Those who study the positions of Alsergsti to poetry and
poets must be discerned his money comes from the spirit of Islam as a religion and
creed and a system, a position that is encouraging him wherever expressed, such as
the Muslim community the new values, away from the vulgarity, which contributed
to the formulation of the standard of religious poetry criticism.
This research deals with an aesthetic discourse that depends on the expressive connotations and the aesthetics of its formation in sculpture, The sculptural works of the artist Saad Al-Basri were chosen as a model, Therefore, it deals with a contemporary plastic topic that benefits art education students and plastic arts students, The method of using materials and their formation methods has evolved and the great change that took place in the taste has developed, As the more knowledge and viewing of artworks increases in research and studies, it leads to an increase in aesthetic taste and aesthetic sense, which is reflected in the artistic achievements of students in the implementation of their work, A field study was conducted to
... Show MoreIbn Khaldun is one of the best Arab Muslims scientists who participated in establishing Arabic Muslims heritage in all different disciplines & directions specially in sociology, neurological & his political theories which showed the development of Arabic philosophy in all scientific disciplines specially his introduction
أن الامم والشعوب لاتستطيع المحافظة على استمرار وجودها وتقدمها ورقيها، إلابفضل إعداد اجيالها المتعاقبة الاعداد السليم المتكامل ، وبقدر ما تحافظ الامم والشعوب على تربية هذه الاجيال للتمسك بدينها ، ومعتقداتها ، واخلاقها ، بقدر ما تحافظ على بقائها وعلو شأنها ، وكما فطنت الامم والشعوب إلى اهمية تربية اجيالها ، فطن اعداؤها الى ضرورة التخريب في جذور البناء الصحيح لتربية الاجيال ( فاطمة ، 1998، ص2).
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The process of doing many kinds of industries , crafts , professions around Islamic Arabian State , they enable us to say that Arab Muslims over their homelands had been occupied various types of crafts and manufacturing before emergence Islam . Moreover Islam encouraged to work within manufacture field . And These matters were clarified through verses of the Holy Qur’an and honored prophetic guidance ( Sunna ) . Whereas Arab Muslims applied principle “ Free of Business “ . They admitted to different social groups such as pact – fellows people to profession or craft which they desire to work . We have to not forget that Arab Muslims had broken all restraints and shackles which had restricted the worker bef
... Show MoreBased on Lyapunov exponent criterion, the aircraft lateral-directional stability during critical flight cases is presented. A periodic motion or limit cycle oscillation isdisplayed. A candidate mechanism for the wing rock limit cycle is the inertia coupling between an unstable lateral-directional (Dutch roll) mode with stable longitudinal (short period) mode. The coupling mechanism is provided by the nonlinear interaction of motion related terms in the complete set equations of motion. To analyze the state variables of the system, the complete set of nonlinear equations of motion at different high angles of attack are solved. A novel analysis including the variation of roll angle as a function of angle of attack is proposed. Furthermore
... Show MoreAbstract:
The research dealt with the study of animal drawings in the fresco, during the Umayyad period, especially in Qusayr Amra and Qasr al-Hayr al-Gharbi. Many imagesto different animals and birds were found and used in various subjects, most notably the hunting and predation scenes.
In the second millennium BC, the international community change at the ancient Near East, There has been a significant developments with the appearance of five kingdoms (Babylon, Assyria, Mitanni, Egypt, and Hatti) called themselves the (Great Powers) and their kings named (Great King), and Correspondence among themselves on behalf of (the brothers), to differentiate themselves from the small kingdoms Minor of them.