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.
ناولت هذه الدراسة إحدى الشخصيات الأمريكية التي تأثرت بواقع السود. كان بوكر تاليافيرو واشنطن أحد الأمريكيين السود ، الذين ولدوا في ظل العبودية وتعرضوا للاضطهاد بعد إلغاء حقوق التصويت وإطلاق قوانين جيم كرو من قبل الولايات الجنوبية. ورأى واشنطن خلال عمليات إعادة الإعمار أحوال السود وكيف كانت معاناتهم قبل الحرب الأهلية في ظل ظروف العبودية التي شملت الإذلال ، والحرمان من حقوقهم المدنية والسياسية، فيما لم يختلف
... Show MoreSome great families in England had competed for the sake of getting authority and power in England.
This competition turned to be a bloody civil war which extended till 1455 and ended with the victory of Henry Tudor whose judgment in England started from 28th of August 1458, consequently a new dynast which is known as (the Tudor)has established
التعددية الثقافية هي مفهوم يتعلق بالمجتمعات التي تضم ثقافات عده، أو العالم الذي يتضمن ثقافات متنوعة؛ فالتعددية هي التنوع الثقافي والفكري؛ وبالتالي هي عنصر إثراء للإنسانية وأساس لوجودها؛ فالتعددية الثقافية تتضمن القبول بالثقافات والافكار الانسانية كلها، وإفساح المجال أمامها للمشاركة في بنا ء الثقافة والفكر العالمي؛ وهكذا فإنها تتمثل في التسامح مع الثقافات والافكار المختلفة الاعتراف بالهويات والخصوصيات
... Show Moreهدفت الدراسة الحالية التعرف على البلادة العاطفية لطلبة الجامعة وكذلك التعرف على معنوية الفروق في البلادة العاطفية تبعاً لمتغيري: النوع (ذكور-اناث) والتخصص الدراسي (علمي –انساني) ، تآلفت عينة الدراسة من (400) طالب وطالبة موزعين بالتساوي حسب النوع والتخصص الدراسي تم اختيارهم عشوائيا من طلبة الجامعة، استخدمت الباحثة مقياس البلادة العاطفية من (اعداد الباحثة) وبعد تطبيق المقياس على عينة البحث واستخراج البيانات با
... Show MoreThis 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 Moreعرض كتاب (وهم التحكم : القوة والسياسة الخارجية في القرن الحادي والعشرين)
Based 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 MoreThe conflicting duality of goodness and evil has a psychological effect on the life of humans, the nature of human beings is originally goodness whereas the tendency of evil flows from the society, therefore the first who found a meaning of evil on earth is kabeel when he quarreled fiercly with his brother who carried in himself all the meanings of goodness and toierance.
In this paper of mine we find that Robaayat Al khayam carries a poetic content of a special meaning in that every expression reflects semantic relationship (the good played a part in the formation lies with and the evil) of which its foundation lies with the human personality (soul), and he (the poet) a scribes it to matters of
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