Background: This study was formulated to compare the effect of 5%hydrofluoric acid in comparison to 37%phosphoric acid with and without the application of silane on bond strength of composite to porcelain. Materials and Methods: Specimen preparation was divided in to two phases, metal-disks fabrication (8mm-diameter and 4mm-thickness) and ceramic veneering. Thirty two specimens were prepared, sandblasted with 50 μm aluminum oxide, and divided into four groups of eight samples. Groups I and III were etched with 37%phosphoric acid while groups II and IV were etched with 5%hydrofluoric acid; and groups I and II were silaneted while groups III and IV were not. Heliobond, and resin composite were applied to each specimen using a plastic transparent split mold (4mm- diameter and 4mm-height). Specimens were stored in distilled water for 24 hours then thermocycled for 100 cycles. Shear bond strength was determined by a Zwick universal machine at a cross-head speed 5 mm/minute. Results: Mean shear bond strength values were 21.02(group I), 23.31(group II), 4.00(group III), and 18.60(group IV). Paired-t revealed that specimens treated with 5%hydrofluoric acid were significantly higher than those treated with 37%phosphoric acid regardless the use of silane. The use of silane dramatically enhanced the bond strength of composite resin to porcelain for both acids. All specimens treated with 37%phosphoric acid without silane showed adhesive failure, while those treated with 5%hydrofluoric acid showed mostly cohesive failure within ceramic. Conclusion: Silane improved the shear bond strength of composite to ceramic, and hydrofluoric acid performed greater bond strength compared to phosphoric acid.
For the first time in Iraq, two species of monogenetic tretamtodes of the genus Dactylogyrus were recorded from gills of Alburnus caeruleus from Tigris river at Al-Zaafaraniya, south of Baghdad during June 1995. The first species, Dactylogyrus sphyrna is characterized by having the seventh pair of marginal hooklets almost twice as large as other marginal hooklets, powerful inner and outer processes of median hooks especially the inner one which is expanded terminally, one connecting bar and long spirally twisted copulatory organ. The second species, Daclytogyrus phoxini differs from the first one by having marginal hooklets of the same size, inner and outer processes of median hooks are not powerful, two connecting bars
... Show MoreThe Contemporary Business Environment is Surrounded by many quick and continues variable and changes which has an effect on the economic units. These variables and changes like the high competition which need many tools to help them to continue and achieve The critical success. So to achieve this they have many competitive strategies like cost leadership strategy, differentiation strategy and focus strategy.
Budget is regarded one of main tools to execute objectives polices and programs of the economic units, beside show how the economic units had execute the available economic resources.
Activity based on budgeting is regarded one of the modern technique in the m
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This study aims to identify the role of forensic accounting in the Iraqi environment, banking stability, and to achieve this goal, we used the field survey method, as it is the most appropriate for studying the phenomenon in question and achieving its objectives.
Where we selected a sample consisting of (50) male and female employees, distributed among five private banks in Baghdad governorate, namely (Ashur International Bank, Development Investment Bank, Iraqi Middle East Investment Bank, Hammurabi Commercial Bank, Khaleej Commercial Bank), and the questionnaire tool was applied to them Designed for this purpose, which consisted of
... Show MoreAbstract:
Through the research, I have briefly discussed the life of Imam Ali and
indicated the interpretation of the Qur'an by language and terminology, the
importance and characteristics of Sahabas', may Allah be pleased with them,
interpretation of the Qur'an. Also, the sayings of Imam Ali, wich included the
explanatory interpretation of the Qur'an by the Qura'n, Sunnah, language, and
correct opinion. I have also indicated the reasons of the Quran's revelation
and the readings of the Qura'n that had been received from him including the
interpretive meaning these readings revealed. Finally, I concluded my
research with the most important results and recommends.
The objective of this research is to analyze the relationship between the Factors of critical success and sustainable competitive advantage, and I have tested Search Company Mu'tasim General Contracting, through applied on a sample of (90) manager, engineer and project manager, spread over sections and the company's projects surveyed. has been selected sector construction industry as one of the sectors vital and important that play a major role in the advancement of Iraq's infrastructure under the current circumstances, which epresent a set of Projects are Mu'tasim General Contracting construction imple
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This research aims to identify the impact of the reciprocal reading strategy on developing the innovative reading skills of fifth-grade secondary school students/ scientific branch. To achieve the goal of the research, an achievement test to measure the academic achievement of fifth-grade secondary school students in Arabic language grammar was prepared, a sample of (60) female students from the secondary school of Al- Bawaba Al-Sharkey for Girls in Baghdad were chosen for the academic year (2019-2020). For the purpose of applying the experiment, the test was applied on a pilot sample consisting of (30) students from the same research community. The researcher herself had taught the three
... Show MoreGiardia lamblia is the worldwide most common intestinal protozoan parasite. It was indicated that Giardia is the most important agent that causes acute and chronic diarrhea in infants, young children and travelers. The aim was to detect the influence of host HLA alleles on the susceptibility to infection with G. lamblia in a sample of Iraqi patients. A total of (40) patients with giardiasis aged (14-39) years were registered. All of them were symptomatic and (40) healthy individuals matched age and sexes were included as controls. All patients were prepared to stool examination to detect G. lamblia and eliminated other pathogens, as well as human leukocyte antigen (HLA) class II alleles (DRB1) typing. The most common detected alleles in pat
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An overall mathematical model for copper pipe corrosion in flowing water was derived based on mass transfer fundamentals where we introduced the effects of boundary layer velocity, bulk flow velocity and the surface oxide protective film on the corrosion rate. A set of experiments were conducted in a straight 10mm diameter copper pipe, flow of water include six velocities of maximum value 7.33m/sec at 200C and 350C. The good agreement between the calculated and experimental corrosion rate values were achieved , the agreement reached 92% .
In many organizations, employees who have high mental skills are the main source of organizational creativity. When a firm does not put creativity as a goal, cannot stand solid against the competition. Nowadays, knowledge is the path to discover the innovation and creativity aspects, This can assist the firm to stand face to face with competition in the market. The importance of this research comes from detecting and knowing the relation between creativity and knowledge to know and detect the influence of organizational creativity on backing the management of knowledge and determine the final results. The problem of research is to trace the role of organizational creativity on knowledge management processes in order to enable the
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