In this research, damping properties for composite materials were evaluated using logarithmic decrement method to study the effect of reinforcements on the damping ratio of the epoxy matrix. Three stages of composites were prepared in this research. The first stage included preparing binary blends of epoxy (EP) and different weight percentages of polysulfide rubber (PSR) (0%, 2.5%, 5%, 7.5% and 10%). It was found that the weight percentage 5% of polysulfide was the best percentage, which gives the best mechanical properties for the blend matrix. The advantage of this blend matrix is that; it mediates between the brittle properties of epoxy and the flexible properties of a blend matrix with the highest percentage of PSR. The second stage included reinforcing the best blend matrix of epoxy-polysulfide (the blend matrix with the best percentage of polysulfide resulted from the previous stage), by different volume percentages of short fibers (Carbon& Glass) separately and randomly. The volume percentages of fibers were (2.5%, 5%, 7.5%, and 10%). The third stage included reinforcing the blend composites with highest percentages of carbon and glass fiber, by different weight percentages of nano-particles (Red mud& Fly ash) separately. The weight percentages of particles were (0.5%, 1%, 1.5%, and 2%). The experimental results showed that blending polysulfide rubber with epoxy increased the damping ratio. As for reinforcement materials, they decreased the damping ratio, where glass fiber composites have significantly higher damping ratio than other composites.
This study examined the effect of transformational leadership four main dimensions (ideal influence, inspirational motivation, intellectual stimulation, individual considerations) as the independent variable on the dimensions of empowerment (knowledge and skill, communication, trust, incentives).
The study sought to achieve a set of goals and most important: the study of the reality of the organization surveyed to identify strategies or policies with employees by transformational leadership, moreover see how much support such a leadership strategy for empowerment and describe the dimensions of empowerment of (knowledge and skill, communication, and trust , and incentives) and the extent of its contributio
... Show MoreMedia theories and studies have provided many diligences on the concept of social media and the circle of influence, including the theory of social marketing which deals with how to promote ideas espoused by the elite in a society to become a recognized social value. The emergence of social networks provided a revolutionary breakthrough, taking the media to unprecedented horizons; and giving its users great opportunities to influence and move across borders without restrictions and censorship, except in a relatively limited manner. So, the emergence of social media has created channels of live broadcasting from its audience in a method of development that changes the essence of the known communication theories; and stops the monopoly of th
... Show MoreThe research entitled "the Iraqi Topics in International Arab Press" is an analytical study of two newspapers: Al-Arab and Al-Hayat published in London from September 1-30, 2013.
The Arab press is one of the cultural monuments Home stretches for culture and media of Arabs outside the Arab Homeland which made them international press targeting public Arab audience's not civil audiences in a particular country and formulating their contents on this basis taking into account intake affairs and issues that have been national or international.
Because of this international presence of the Arab press, these newspa
... Show MoreIn this paper, we will discuss the performance of Bayesian computational approaches for estimating the parameters of a Logistic Regression model. Markov Chain Monte Carlo (MCMC) algorithms was the base estimation procedure. We present two algorithms: Random Walk Metropolis (RWM) and Hamiltonian Monte Carlo (HMC). We also applied these approaches to a real data set.
This conducted research, (The Scientific Efforts of Ahmed Mustafa Al-Maraghi) deals with Al-Maraghi's life, birth, upbringing, characteristics, title, family and religion secter, as well as his general biography. And his relationship with scholars, his learning and teaching, and the introduction of the Muhammed Abdo School and the College of Dar Al Uloom, and finally the discussion of his scientific, social and political poin of view, as an interpreter of twentieths century, was appointed as the president of Al-Azhar and Ifta during the days of the royal era, and he studied at the College of Dar Al-Uloom
The visual stimulus is the effective force in visual attraction that achieves visual and perceptual co-optation and is important in wooing the recipient, and many procedural processes in the design are interpreted on it as the visual stimulus achieves visual comfort and a sense of pleasure and gives (place) the interior space a transformation in its plastic structure as well as arousing attention through The kinetic rhythm and the formal diversity, which increases the possibility of breaking the routine and traditional constraints of design patterns through the coating and encapsulation of the vertical and horizontal levels . Thus, the research problem was launched based on the following question: What are the stimuli of the visual stimu
... Show MoreHowever, the effects of these ideas are still evident
Think of those who follow the footsteps of Muslim scholars and thinkers.
Intellectual source of Gnostic Gnar
And in dealing with issues of Islamic thought
Annalisa intersecting trends of thought, Minya who melts in Masarya and supported him and believes in Bo and extremist Vue,
Lea, trying to throw it with a few times, looks at Elya look
There are those who stand in the opposite position
There are those who stand in a selective compromise, but this school of thought remains
G - the features of Islamic thought that believes in the mind and Imoto in the defense of
An intellectual station and generalized bar
Creed. In his study, the researcher wi
The aim of the research is to identify the attitudes of Iraqi youth
towards volunteering work by using the survey method and the scale
tool to identify what young volunteers can carry from the attitudes
towards volunteering work because the phenomenon of volunteer
work is of great importance in society. The scale was applied to
(525) volunteers among Iraqi youth. The research reached a set
of results, the most prominent of which is the existence of positive
trends among young people towards volunteering work, meaning
that Iraqi youth volunteers have awareness of the concept of
volunteering correctly. As for their goals of volunteering, they are
humanitarian and social goals for the advancement of society, an
Resveratrol is polyphenolic compound has many biochemical and biological effects on several organs. Therefore, resveratrol can be used to treat many diseases. The aim was to evaluate resveratrol safety when used in a parenteral single bolus dose. This study was conducted on 60 mice (30 males and 30 females). Each male and female mice divided into 6 groups (five mice per group). All mice groups given 1% DMSO and five different doses of resveratrol (5, 2.5, 1.25, 0.625, 0.312) gm/kg intraperitonially given to five groups respectively. The mice were continuously monitored during 14 days. The number of deaths, changes in general behavior, changes in physiological activity, and signs of toxicity were reported. On day 15 blood was
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