Background: Dental stone casts come into contact with impression materials and becomes susceptible to cross contamination from saliva and blood. This study was done to evaluate the physical and mechanical properties of dental stone type IV after treatments with various disinfecting agents and regimes (methods). Materials and Methods: Type IV dental stone and different types of disinfecting agents were used and divided into seven groups: G1: dental stone without disinfection (control group), G2: dental stone mixed with silver nitrate powder 0.5% , G3: dental stone mixed with silver nitrate powder 1%, G4: dental stone mixed with copper sulfate powder 0.5%, G5: dental stone mixed with copper sulfate powder 1% ,G6: dental stone immersed in propanol 70% and G7: dental stone immersed in ethanol 70%.Setting time, linear setting expansion, surface detail reproduction, compressive strength of type IV dental stone as well as compatibility with auto mixing addition silicone impression material were evaluated. The statistical analysis were conducted by ANOVA test followed by LSD test (p<0.05), also chi square test was used. Results: The compressive strength, linear setting expansion, surface detail reproduction and compatibility of stone specimens was affected to a higher extent by mixing with silver nitrate powder 1%, copper sulfate powder 1% while treating the stone specimens with the disinfecting powders at low concentrations as well as immersion of stone specimens in either ethanol or propanol for 15 minutes produce less effect on the previous tested properties. Conclusion: Silver nitrate 0.5%, copper sulfate 0.5% powders as well as 15 minutes immersion in 70% ethanol or 70% propanol did not promote adverse alterations in most of evaluated properties of type IV dental stone.
That the electronic payments system plays an important role in the effectiveness of commercial banks by attracting domestic or foreign investors, especially in the banking sector , It must keep abreast of global developments and technology in the field of banking that lead to the effectiveness of the bank by providing modern banking services and good customer service that improves the reputation of the bank, as well as develop its activities and promotes economic development at the country level , The technological progress of the bank will increase the speed of conducting banking operations, accuracy and safer , here should be laws and regulations related to electronic payment systems keep pace with the la
... Show MorePrednisolone (SAID) was conjugated with ibuprofen (NSAID) through an amino acid (glycine) as a spacer arm to synthesize the following compound:
Prednisolone – glycine – ibuprofen.
The method employed consists of converting the carboxylic acid function of (R,S) – ibuprofen – glycine to the highly reactive acid chloride and subsequent reaction with the C21 hydroxyl group of prednisolone. This reactive intermediate was found to react as well with the C17 tertiary hydroxyl group of the steroid to form three compounds and eight diastereomers. These results were confirmed by T.L.C, and the desired compound was separated by column chromatograph
... Show MoreWellbore instability and sand production onset modeling are very affected by Sonic Shear Wave Time (SSW). In any field, SSW is not available for all wells due to the high cost of measuring. Many authors developed empirical correlations using information from selected worldwide fields for SSW prediction. Recently, researchers have used different Artificial Intelligence methods for estimating SSW. Three existing empirical correlations of Carroll, Freund, and Brocher are used to estimate SSW in this paper, while a fourth new empirical correlation is established. For comparing with the empirical correlation results, another study's Artificial Neural Network (ANN) was used. The same data t
... Show MoreThe nature of the political system of any country in the international system must have an impact on the policy of the State, whether in the interior or exterior, both regional and international, Turkey is one of the most important countries in the Middle East, which have a place and effectiveness on the surrounding environment, hence the importance of research lies in its political system and the transfer of power in it and its transformation from the form of the parliamentary system to the presidential system of the repercussions of the task and mutual effects between Turkey and the countries of the surrounding region in terms of the extent of achieving political stability in the Turkish interior or not and how this can be refl
... Show MoreHuman resources have been regarded as the most important asset for any organization because of its essential part in achieving the sustainable competitive advantage and survival. Managing human resources is very challenging and requires an effective bundle of practices that contribute to attaining the organizational goals. This study tries to confirm the importance of HRM practices in small businesses which came to play a vital role in the economies of the world, through clarifying the influence of HRM practices on the organizational performance, using a mediating variable (employees’ outcomes). Also the study attempts to highlight the key role of governmental support from view point of small businesses, through verifying the significant
... Show MoreThe Moisture damage is considered as one of the main challenge for the experts in the field of asphalt pavement design. The aims of the present study is to modify moisture resistance of the asphalt concrete by utilizing ceramic fibers as a type of reinforcement incorporated with hydrated lime. For this purpose, a penetration grade of the asphalt cement (40-50) was utilized as a binder with an aggregate of the maximum nominal size of 12.5mm and mineral filler limestone dust. A series of specimens has been fabricated by utilizing 0.50, 1.0, 1.5, and 2.0 percentages of ceramic fibers. For each of these contents, another subsequent group of specimens with hydrated lime with 0.0, 1.0, 1.5, and 2.0 percentages were moulded. For the additi
... Show MoreThe skill of management educational activities gradually grow with the experience, but they differ from personal skill educator to another, because each style nanny personally and the way to work. There educator and active movement and vitality that look like happiness and clear during the implementation of the activity, and the other runs educational activities quietly, efficiently and without emotion and clear (dry, 2001: p. 274). And the stage of childhood is one of the most important stages that are based upon the future life as a whole because the man also confirmed by the School of analysis psychological is the son of his childhood and the best example to us what the Holy Prophet Muhammad (peace be upon him): (Every child i
... Show MoreIn this paper a stirred-bed performed of the copper catalyzed synthesis of ethylchlorosilanes from silicon and ethyl chloride was described. A Si-catalyst mixture prepared by reaction of CuCl and Si was employed. The compositions of products were mainly ethyltrichlorosilane, diethyldichlorosilane, and ethyldichlorosilane and mainly depended on the extent of Cu in the mixture and the reaction temperature. A promoting effect on the extent of adsorption was observed on the addition of certain additives. The kinetic data revealed the direct depended of the reaction rate on C2H5Cl pressure.