Objectives: The purpose of this in vitro study was to compare the effect of adding a poloxamer surfactant to the irrigant solutions on its cleaning efficiency. Design: In this study the roots of extracted permanent premolar teeth were used and evaluated by using Scanning Electronic Microscopy (SEM). Materials and Method: 72 human single tooth of permanent premolar (8 for each group) were used in this in vitro study. Roots after sectioning at cervical area to get 15 mm were embedded in a plastic container filled with impression silicon, then instrumented with ProTaper rotary instruments till size F4. Each group (8 root) were irrigated with one of the nine solutions used in study: three concentrations of NaOH [5% (A1), 2.5%(A2), 0.5%(A3)], three concentrations of NaOH with Poloxamer surfactant [5% (B1), 2.5% (B2), 0.5% (B3)], NaOCl 5.25% (C1), NaOCl 5.25% with Poloxamer surfactant (C2), and Normal Saline (D). After instrumentation, each tooth was finally washed with normal saline. Then by using diamond disc, all roots were sectioned longitudinally in buccolingual direction to obtain two halves of each root, the more intact root was selected to be prepared for scanning electron microscopy test. Finally, the data was analyzed by using the SPSS 25 program with a non-parametric Kruskal-Wallis test. Additionally, scores were analyzed by using the chi-square test. The significance level for all tests was set at p ≤ 0.05. Results: the study showed that Sodium hypochlorite was higher in smear layer removal than that of Sodium hydroxide, and there was also a significant increase in the cleaning efficiency of sodium hydroxide with increasing concentration of solutions. Conclusion: The adding of a poloxamer surfactant didn't significantly increased the cleaning efficiency of both solutions used. No significant difference between NaOCl and NaOH
The purpose of the study is to analyze the extent of the impact of liquidity as an independent variable on profitability as an intermediate variable and the value of banks listed in the Iraq Stock Exchange as a dependent variable, as the research problem is summarized by the fact that most banks focus on profitability as a phased goal without focusing on maximizing its value as a strategic goal by enhancing the wealth of owners and shareholders. On the long term, the research community is represented by the banks listed on the Iraq Stock Exchange, while the research sample was deliberately chosen, which included three private banks such as Baghdad Commercial Bank, the Iraqi Commercial Bank and the Iraqi Investment Bank, an
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The study aimed to determine the impact of energy for the north and south magnetic poles on the the growth of bacteria isolated from cases of tooth decay, 68 swabs were collected from surfaces of faulty tooth, the detected of Staphylococcus aureus
... Show MoreThe electrical properties of polycrystalline cadmium telluride thin films of different thickness (200,300,400)nm deposited by thermal evaporation onto glass substrates at room temperature and treated at different annealing temperature (373, 423, 473) K are reported. Conductivity measurements have been showed that the conductivity increases from 5.69X10-5 to 0.0011, 0.0001 (?.cm)-1 when the film thickness and annealing temperature increase respectively. This increasing in ?d.c due to increasing the carrier concentration which result from the excess free Te in these films.
In this research the Cobalt Oxide (Co3O4) films are prepared by the method of chemical spray pyrolysis deposition at different thicknesses such that (250, 350, 450, and 550) ± 20 nm. The optical measurement shows that the Co3O4 films have a direct energy gap, and they in general increase with the increase of the thickness. The optical constants are investigated and calculated such as absorption coefficient, refractive index, extinction coefficient and the dielectric constants for the wavelengths in the range (300-900) nm. The electrical conductivity (σ) and the activation energies (Ea1, Ea2) have been investigated on (Co3O4) thin films as a function of thickness. The films
... Show MoreThis research includes a study of dezincification by corrosion from brass alloys in three types of media, which are acidic solution, basic and slat solution in different percentages. The study show the higher dezincification occurs in basic solution which decrease the fatigue properties where the fatigue properties are inversely proportional with dezincification.
Because of the new political stage that Iraq is living in, which called on researchers to choose the subject of political marketing and increase its effectiveness through strategic intuition. The problem of research was reflected in the following question: How can strategic intuition be used to achieve efficiency in marketing marketing to achieve voter acceptance and achieve political success later on? ).
The research derives its importance from the fact that it is related to the developments in the concepts and areas of marketing in various fields, and it has a role in identifying the gain of new markets, where it is specialized to provide a political product and identify the mechanism of marketing the p
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This paper is dealing with an experimental study to show the influence of the geometric characteristics of the vortex generators VG son the thickness of the boundary layer (∂) and drag coefficients (CD) of the flat plate. Vortex generators work effectively on medium and high angles of attack, since they are "hidden" under the boundary layer and practically ineffective at low angles.
The height of VGs relative to the thickness of the boundary layer enables us to study the efficacy of VGs in delaying boundary layer separation. The distance between two VGs also has an effect on the boundary layer if we take into
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The research aims to determine the required rate of return according to the Fama and French five-factor model, after strengthening it by adding the indebtedness factor to build the Fama and French six-factor model FF6M-DLE. The effect of the indebtedness factor on the company's profitability and the real value of the ordinary shares calculated according to the (equivalent ascertainment) model and its suitability with the company's situation, and an analysis of the fluctuation between the market value and the real value of the ordinary stocks.
This study included preparation for the unsaturated polyester samples before and after reinforced by Alumina oxide powder and copper oxide powder of different volume fraction amounting (3%,5%,8%). And this reearch included study of some of mechanical properties such as (hardness,compressive and wear).The results showed that increase of the hardness and compressive strength after the reinforced and increase with the volume fraction increase.As the wear test show that the wear rate increases with applied load from the different load(5,10,15)N,and the wear rate decreases with the volume fraction increase.