The efficiency of Nd:YAG laser radiation in removing debris and smear layer from prepared root
canal walls was studied. Fifty-seven human extracted single rooted anterior teeth were divided into three
groups. A group that was not lased is considered as a control group. The remaining teeth were exposed to
different laser parameters regarding laser energy, repetition rate and exposure time. For the case of the set of
parameters of 7 mJ laser energy, the cleaning was maximum at 3 p.p.s. repetition rate for 3 seconds exposure
time for, the coronal, middle and apical thirds. Above and below this energy level, there was an overdose
(melting) or under dose (no effect). Nevertheless for 10mJ laser energy case, the cleaning efficiency was
obvious but less than the 7 mJ case
Despite the importance of this term in linguistics and rhetoric ancient and modern literary forms in general, is that it is possible to use in clarifying the foundations of the relationship hidden and manifest between shapes in models art adjacent or successive spatially, as the artwork plastic in general and sculpture in particular consists of formal structure somewhat similar to the structure in any language text and we can decode these blades structure and analyze the implications and come to their meanings and re-read and interpreted under the guidance of the concepts and techniques of neighboring developed primarily for linguistic analysis of texts or launched from their references. This split search to four chapters included the fi
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Purpose: Providing practical knowledge of the requirements of a detailed feasibility study for selecting the investment project.
Findings: Directing the private sector towards investing in productive projects - the pre-cast reinforced concrete project - as it achieves a financial return as well as providing Providing foreign currencies by reducing imports and exploiting available natural resources
Practical implications: The importance of a detailed feasibility study to determining whether the project can be implemented or not.
The precast concrete method is one of the best modern c
... Show MoreThe objective of the present study is to determine the effect of Kaolin as a fuel oil additive to minimize the fireside corrosion of superheater boiler tubes of ASTM designation (A213-T22) by increasing the melting point of the formed slag on the outside tubes surface, through the formation of new compounds with protective properties to the metal surface. The study included measuring corrosion rates at different temperatures with and without additive use with various periods of time, through crucible test method and weight loss technique.
A mathematical model represents the relation between corrosion rate and the studied variables, is obtained using statistical regression analysis. Using this model,
... Show MoreThe aim of the research is to identify the extent of the direct and indirect relationship of the population growth of the cities as a result of the urbanization process witnessed by the Arab region for the urban development of the city structures and their formative structures, changing the planning criteria of some cities and the extent of their changes in spatial and temporal dimensions and their relation to the standards of the western cities. In changing the concept of the modern Arab city, such as the emergence of new functional uses affecting the change in the pattern of formal formations of its urban fabric associated with its ancient morphology and distinctive human nature. The research seeks to identify the extent to which plann
... Show MoreThe fluctuation and expansion ratios have been studied for cylindrical gas-solid fluidized columns by using air as fluidizing medium and Paracetamol as the bed material. The variables were the column diameter (0.0762, 0.15, and 0.18 m), static bed height (0.05, 0.07, and 0.09 m), and air velocity to several times of minimum fluidization velocity. The results showed that both the fluctuation and expansion ratios had a direct relation with air velocity and an inverse one with column diameter and static bed height. A good agreement was between the experimental results and the calculated values by using the correlation equations from the literature.
The psychological burnout is considered one of dangerous phenomenon’s which appeared in the 70s of the 20th century and suffered by most of the society classes. It is a term which the wide uses and various meaning like emotional, mental, and physical exhaustion and chronic weak exhaustion. The presented research aims t identify the psychological burnout as for the Kindergarten teacher and the differences significance according to the variations (Kindergarten type: private or govern mental). The research sample contains 400 female teachers divided to 170 governmental Kindergarten teachers and 230 private Kindergarten teachers. The researcher prepared a measurement method to measure the psychological burnout for those teachers after
... Show MoreThe subject of children's rights in the modern era of the priorities of educators , because the child in the community is the future , which is held by the hope which is the basis for society in the renaissance and progress so quickly communities to prove these rights through its various institutions and issued legislation and held numerous conferences and taking specialists the field of childhood Aatron aspects of this rights and Aasalunha including a benefit for children until tomorrow for the rights of children , psychological and social health and educational . Therefore, the current study focused on the awareness of parents and educators of children's rights as individuals most closely satisfying their needs and rights. The
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