Static loads exposing to mechanical components can cause cracks, which are lead to form stress concentration regions causing the failure of structure. Generally, from 80% to 90% of structure failure is due to initiation of the cracks. Therefore, it is necessary to repair the crack and reduce its effect on the structure where the effect of the crack is modelled as an additional flexibility to the structure. In the last few years, piezoelectric materials have been considered as one of the most favourable repairing techniques. The piezoelectric material converts the applied voltage on it to a bending moment to counter the bending moment caused by the external load on the beam at the crack location. In this study, the design of the piezoelectric materials used to repair effect of crack on the mechanical behaviour of beam subjected to static loads is analytically achieved. This design includes calculating of desired dimensions of the material with the required voltage applied on it. The additional flexibility is expressed in term of a proposed unitless factor which can be calculated depend on experimental work. The results show that increasing the patch thickness increases the beam resistance to crack and load effects, while increasing the length of the piezoelectric material reduces the magnitude of the voltage required to repair the cracked beam.
A charge transfer complex formed by interaction between nitron as electron donor with curcumin(1 ) as electron acceptor in ethanol at the temperature of theroom to form a colored complex. The optimum conditions of complex formation were investigated by Univariate method. The linearity range of complex was (3.124– 53.11) μg.mL-1 at 442 nm with molar absorptivity (1858.33) L.mol-1.cm-1, Sandell's sensitivity (0.1681μg.cm-2), and with a correlation coefficient (0.9935). Both modified attapulgite and modified attapulgite – complex have been characterized by using , FTIR, SEM, AFM, and XRD. Theadsorption behaviourof complex onto the modified attapulgite has been researchedthrough the variation of the parameters like the adsorbent weight, p
... Show MoreIraq has suffered since 1991 from international sanctions imposed on it by the dictatorial regime that existed at the time, invading Kuwait, which led to the decline of the status of Iraq and the isolation of international and regional (Arab) and clear Iraq as a strange entity living within its regional environment, after April 2003 did not change much In fact, there were no signs of détente before the Arab League summit in Baghdad in 2011, and the signs of a break in the stalemate in inter-relations over the past years have become evident. Disruption and refraction was not high (Islamic Republic of Iran, Turkey, Syrian Arab Republic, Hashemite Kingdom of Jordan, Saudi Arabia, Kuwait). Each side is governed by perceptions about Iraq, es
... Show MoreThis research studies the development and synthesis of blended nanocomposites filled with Titanium dioxide (TiO2). Blended nanocomposites based on unsaturated polyester resin (UPR) and epoxy resins were synthesized by reactive blending. The optimum quantity from nano partical of titanium dioxide was selected and different weight proportions 1%, 3%, 5%, and 7% ratios of new epoxy are blended with UPR resin. The dielectric breakdown strength and thermal conductivity properties of the blended nanocomposites were compared with those of the basis material (UPR and 3% TiO2).The results show good compatibility epoxy resins with the UPR resin on blending, dielectric breakdown strength values are higher while thermal conductivity values of
... Show MoreThe centers of cities and historical quarter are exposed to a severe threat to the values of the physical and legal urban environment as a result of the value deterioration and the emergence, emergence and spread of new values on the intellectual and urban context, which generates the loss of the urban environment for its spatio-temporal continuity, flexibility, adaptation and continuity, and thus urban obsolescence, Hence the problem of the research in “the lack of comprehensiveness of studies on the phenomenon of urban obsolescence and its impact on the decline in the values of the quality of the built environment in historic
... Show MoreSome may think that the games, especially the folk games, are just a means of entertainment and fun and children may resort to them to alleviate the tension they are experiencing at home or school, but the truth is that they carry values and meanings that can be invested in education because they contribute to the development of the personality of the child and enhance self- confidence. The objective of the research is to learn how to use folk games to develop children's acting and performance skills in the kindergartens.
The research included a theoretical introduction of three sections: the first section: education through play. The second section: the folk tale and the development of imagination and the
... Show MoreWitch stories are part of American popular culture, and this culture is extremely influenced by a continuing reliance on its past. The modern obsession of Americans with witches, whether real or metaphorical, is related to politics especially when it came to issues of gender politics. This article exposes a modern image of the female character seen from a male author point of view. John Updike, influenced by the changes that happened to women within second wave of feminism, attempted to write The Witches of Eastwick (1984). Actually, he presented women who did have a sort of careers. His witches are professional active and dynamic. What do witches stand for in American Culture? Why did Updike choose to write
... Show MoreElectric Quadrupole transitions are calculated for beryllium isotopes (9, 10, 12 and 14). Calculations with configuration mixing shell model usually under estimate the measured E2 transition strength. Although the consideration of a large basis no core shell model with 2ℏtruncations for 9,10,12 and14 where all major shells s, p, sd are used, fail to describe the measured reduced transition strength without normalizing the matrix elements with effective charges to compensate for the discarded space. Instead of using constant effective charges, excitations out of major shell space are taken into account through a microscopic theory which allows particle–hole excitations from the core and model space orbits to all higher orbits
... Show MoreKnowing the Messengers, peace and blessings be upon them, and explaining their obligatory, impossible, and permissible qualities is a legal necessity. It is a rooting of the faith, a means of understanding the Sharia, and a preventer from falling into the scourge of denial and bad manners against them. Therefore, sound belief in their presence is a major reason for the validity of the faith in the aspect of divinity and unseen hearing. Studying the status of prophethood is an urgent necessity in a time in which knowledge is scarce and attachment to the Messenger, may God Almighty’s prayers and peace be upon him, his family, and his companions, is weak, and suspicions and ideas hostile to the faith abound until we begin to hear - unfort
... Show MoreAim: Rats are accused in disseminating many zoonotic diseases. This study aimed to isolate and identify bacteria from internal organs of rats captured in Baghdad City, Iraq. Materials and Methods: A total of 120 black rats (R. rattus) were trapped from different areas in Baghdad city. Rats were kept in individual plastic cages for 3 h before euthanizing. Deep pharyngeal swab, intestinal content, urine, and pieces of the liver and spleen, lung, kidney, and brain were obtained aseptically. The specimens were inoculated into peptone water and incubated at 37°C for 24 h for enrichment. A loopful of each specimen was then subcultured onto MacConkey Agar, Blood Agar, and Mannitol Salt Agar. CHROMagar O157 H7 and CHROMagar Listeria were u
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