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.
مشكلة البحث واهميته :
يعد الغضب من المظاهر الانفعالية الشائعة في مرحلة الطفولة المبكرة وذلك بسبب كثرة المواقف المثيرة لغضب الطفل في هذه المرحلة ، كما ان الطفل في هذه المرحلة سرعان ما يكتفي في كثير من الاحيان بان غضبه وبكائه طريقة سهلة للوصول الى ما يريد . ويعد المختصون في هذا المجال ، بان نوبات غضب الاطفال ، هي شيء عام طبيعي عند جميع الاطفال ، لكن عندما تكون نوبات عنيفة
... Show Moreوهدف البحث إلى التعرف على الاوهام الايجابية فضلاً عن التعرف على الفروق في الاوهام الايجابية بين الطالبات على وفق متغير الحالة الاجتماعية (متزوجة – غير متزوجة) والتخصص الدراسي (علمي – انساني) والمرحلة الدراسية (اول- رابع)، تألفت عينة البحث من (120) طالبة من طالبات جامعة بغداد -كلية التربية للبنات وكلية العلوم للبنات، وتم تطبيق مقياس البحث - مقياس (الاوهام الايجابية) وهو (من إعداد الباحثة)، وقد اسفرت نتائج البحث عن:
... Show MoreThis research deals with the ideas of Imam Muhammad bin Al-Waleed bin Khalaf bin Sulaiman bin Ayyub , Al -Qurashi, The Moroccan, The Andalusian, Al-Maliki. He was known as Abu Bakr Al-Tartoushey , where thesis deals with the details of his personal life and as well as his scientific path as well as his works, and also covered the views of jurisprudence in the personal status and especially on the subject of divorce and inheritance,
ملامح من فكرة القانون الطبيعي في حضارة العراق القديم
Abstract Since unmethylated CpG motifs are more common in DNA from bacteria than vertebrates, and the unmethylated CpG motif has recently been reported to have stimulatory effects on lymphocytes, we speculated that bacterial DNA may induce inflammation in the urinary tract. To determine the role of bacterial DNA in lower UTI, we intraurethrally injected prokaryotic DNA (extracted from E. coli) in white mice and performed histopathological study for the kidneys and urinary bladders, 24 h after the exposure. The results showed infiltration of inflammatory cells, shrinkage of glomerulus and increase the capsular space, as well as edema formation in kidney tissues. Moreover, urinary bladder sections showed infiltration of inflammatory cells.
... Show MoreMedia and communication's research are varied in accordance to research approaches' variety which seeks to reach convergent social, psycholo
... Show Moreمشكلة البحث:
بين الحين والآخر تتصاعد الصيحات مطالبة بإصلاح النظام التعليمي لكي يتوافق هذا النظام مع ما يحدث في العالم من تطورات علمية وتكنولوجية تترك بصماتها على مختلف قطاعات الحياة .
ويعد المعلم وبلا شك ركنا أساسيا في هذا النظام ،وذلك لما للمعلم من تأثير أساسي في عملية التعليم والتعلم . ماذا يجدي إذا ما طورنا مناهجنا، واحسنا مباني مدارسنا، وأكثرنا من الوسائل والتقنيات ،ولم نوفر المع
... Show MoreBohemia AL-Kharab for Salah Salah Which contain 477Paper deal With History of Nathion This Novel Has a different styl from another IraQis Novels, this Novel has no conversation this is the basic reason Which hav this research .
The novel have 3 versions , the first one deal with explain the text in different ways , the second contains the realation ship between the text and the reader .
Which appear very clear in novel from up to down , whil the third one and the last explaine
The hermonologiq
The time bylose the relation in the novel.
The last thing is the conclusion which has the simple things conclude by the researcher from several readings to the novel
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... Show MoreThe art of designing clothing fabrics is a multidisciplinary design important and difficult because it is linked to man and his personality and his tastes and habits and behavior being is a form of creative expression here came the problem of the research , which are summarized by asking the following: Is the similar role in the designs of clothing fabrics The second chapter included two themes design fabrics the symmetry in the design of fabrics the third chapter included research procedures adopted descriptive analytical method to reach the goals of the research and consisted of the research community (9) models of the designs fabrics Iraqi either the research sample was selected (5) models of society current search and search tool Vtm
... Show MoreThe Research aimed for identification the significant of health problems that occurrences through
misused of computer for those whom attaches with more than two hours daily and to identification the
nature of demographical characteristics variables and that related variables with using computer. Also to
know the level of user’s knowledge for some attaché’s equipment's and finally creating a new suggested
measurement scale for studying health problems that were occurred through misused of computer.
Creating questionnaire includes several domains (Social problems – family environment, Social problems –
external environment, some health problems attaches with related equipment's, psychological problems,
and hea