Background: Lack of durability of the bond of the dental adhesive systems to tooth structure is one of the most important problems in tooth colored restorative work. This in vitro study was performed to evaluate the effect of 2% chlorhexidine gluconate(CHX) on dentin bond strength by using total etch adhesive system at twenty-four hours and three months of water storage. Material and methods:A flat dentin surface was prepared for forty sound human maxillary premolar teeth which were acid etched with 36% phosphoric acid gel after being divided randomly into four groups of ten teeth each according to storage time and CHX application, theCHX was applied for 60 seconds before adhesive application for groups I and III which were tested after twenty-four hours and three months respectively, while the distal water was applied for 60 seconds before the application of adhesive for group II and IV which were tested after twenty-four hours and three months respectively.The Prime and Bond® NT™ adhesive (Dentsply) was applied and cured, Composite (Ceram X mono, Dentisply) was applied through special mold with 2 mm thickness and light cured, Then all specimens were stored in distilled water 37oC until the time of testing of each group.Shear bond strength test was performed at the end of the storage period (24 hours or 3 months). Results:T-test results showed high statistically significant reduction in shear bond strength (SBS) in non CHX group IV (tested after 3 months) compared to non CHX group II (tested after 24 hours)(P< 0.01). In CHX groups I (tested after 24 hours) and III (tested after 3 months), results showed no statistically significant differences in shear bond strength(p> 0.05).On the other hand result showed statistically no significant differences between groups I and II in 24 hours shear bond strength (P> 0.05). After 3 months water storage, there was statistically high significant differences between the groups III and IV (P< 0.01). Conclusion: the use of 2 % CHX glocounate solution after acid etching and before bonding of dentin have no adverse effect on immediate bond strength (24 hours storage), and was effective in reducing degradation of resin-dentin bond interface after three months of water storage.
Applying load to a structural member may result in a bottle-shaped compression field especially when the width of the loading is less than the width of bearing concrete members. At the Building and Construction Department – the University of Technology-Iraq, series tests on fibre reinforced concrete specimens were carried out, subjected to compression forces at the top and bottom of the specimens to produce compression field. The effects of steel fibre content, concrete compressive strength, transverse tension reinforcement, the height of test specimen, and the ratio of the width of loading plate to specimen width were studied by testing a total of tenth normal strength concrete blocks with steel fibre and one normal s
... Show MoreThe problem of research is that there are differences between learners in processing in formation in general and there is variation at the learners level perform scrolling skill of the passes up and down by the volley ball .Therefore the researchers decided to conduct astudy through which identify the relationship between information processing and the skill of scrolling from the top and bottom by the volleyball. The researchers used the descriptive approach by themethod of interconnectivity .Asampleconsist of21 students from first staye in collage of physical education and sports science for Girls(university of Baghdad) and attest has been applied(process information and scroll up and down) on the research sample after the required
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In this study, a one-dimensional model represented by Butler-Volmer-Monod (BVM) model was proposed to compute the anode overpotential and current density in a mediator-less MFC system. The system was fueled with various organic loadings of real field petroleum refinery oily sludge to optimize the favorable organic loading for biomass to operate the suggested system. The increase in each organic loading showed higher resistance to electrons transport to the anode represented by ohmic loss. On the contrary, both activation and mass transfer losses exhibited a noticeable decrement upon the increased organic loadings. However, current density was improved throughout all increased loads achieving a maximum current density of 5.2 A/m3
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Within the framework of big data, energy issues are highly significant. Despite the significance of energy, theoretical studies focusing primarily on the issue of energy within big data analytics in relation to computational intelligent algorithms are scarce. The purpose of this study is to explore the theoretical aspects of energy issues in big data analytics in relation to computational intelligent algorithms since this is critical in exploring the emperica aspects of big data. In this chapter, we present a theoretical study of energy issues related to applications of computational intelligent algorithms in big data analytics. This work highlights that big data analytics using computational intelligent algorithms generates a very high amo
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Titanium dioxide TiO2 has been widely utilized in cleaning and sterilizing material for many clinical tools sanitary ware, food tableware and cooking and items for use in hospitals. Titanium dioxide TiO2 non toxicity and long term physical and chemical stability. It has been widely used decomposition of organic compounds and microbial organisms such as cancer cell, viruses and bacteria as well as its potential application in sterilization of medical devices. The aim of the study the effect of titanium dioxide TiO2 on some Gram negative bacteria and study their effects on some virulence factors and chromosomal DNA.In this study, we obtained (E. coli ? Proteus mirabilis, Proteus vulgaris ? Pseudomonas aeruginosa ? Klebsiella pneumonia and Ac
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This study is a complementary one to an extended series of research work that aims to produce a thermodynamiclly stable asphalt –sulfur blend. Asphalt was physically modified wiht different percentages of asphaltenes , oxidized asphaltenes and then mixed with sulfur as an attempt to obtaine a stable compatible asphalt-sulfur blend. The homogeneneity of asphalt-asphaltenes[oxidized asphaltenes]-sulfur blends were studied microscopically and the results are prsented as photomicrographs. Generally more stable and compatible asphalt-sulfur blends were obtained by this treatment.
The aim of organizational contemporary is development man power active, in spit-of there are littlie resources. But in the Iraqi environment there are too much resources with performance inhabiting. specially in the ministry of water resources (sample of this research), about dryness and lower levels of rivers. There for this study have some important variable, it is ethical leadership & transformational leadership as (independent variable), and Perceived organizational support(dependent variable). Over here to invest with authority on the problem of research, is weakness harmony between employed perception and the pattern of leadership. We find decline in of reaction of organ compound between the variable to weaken high perf
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The job that confronts players with the effectiveness of shooting with an air rifle is high, so it requires necessary functional adaptations that differ in their degrees from other sports. Regular training in air rifle shooting leads to physiological changes in most of the body's internal systems, and changes and responses can be identified. The functional accompanying physical activity through the presence of body components that reflect these physiological changes in the form of changes in some components, and the importance of research lies in studying the physiological changes accompanying the maximum physical effort and the consequent development of the level of achievement in the effectiveness of shooting with air rifle and body
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The present work involved preparation of new hetro cyclic polyacrylamides (1-9) using reaction of polyacryloyl chloride with 2-aminobenzothiazole which prepeard by thiocyanogen method in the presence of a suitable solvent and amount tri ethyl amine (Et3N) with heating. The structure confirmation of polymers were proved using FT-IR,1H-NMR,C13NMR and UV spectroscopy.Other physical properties including softening and melting points, and solubility of the polymers were also measured.