Abstract: Objectives: To investigate the effect of temperature elevation on the bonding strength of resin cement to the zirconia ceramic using fractional CO2 laser. Background: Fractional CO2 laser is an effective surface treatment of zirconia ceramic, as it increases the bonding strength of zirconia to resin cement. Methods: Thirty sintered zirconia discs (10 mm diameter, 2 mm thickness) were prepared and divided to three groups (N=10) and five diffident pulse durations were used in each group (0.1, 0.5, 1, 5 and 10 ms). Group A was treated with 10 W power setting, group B with 20 W and group C with 30 W. During laser irradiation, temperature elevation measurement was recorded for each specimen. Luting cement was bonded to the treated zirconia surfaces and cured for 30 seconds. Shear bond strength was evaluated by a testing machine (universal) with bond failure mode determination. Results: The lowest temperature elevation measurement of the irradiated specimen which gave maximum shear bond strength was about 1.6±0.3 Ċ higher than ambient room temperature (27±0.2 ºC). Apparent micromechanical irregularities were seen in the treated samples and cracks formation with increased pulse duration and power setting were also observed. Conclusions: The temperature elevation is a vital factor in the surface roughness of zirconia ceramic with fractional CO2 laser irradiation and the lowest temperature elevation at best shear bond strength of zirconia ceramic to the resin cement is satisfied with the shorter pulse duration of 0.1 millisecond.
Science occupies great importance in Islamic thought. Science and learning are considered an essential part of Islamic teachings, and this importance appears in several aspects,Among them is thatScience as a means of understanding religion :Science is a means of understanding the teachings of the Islamic religion. Islam encourages thinking and rational research to understand the Holy Quran and the Sunnah of the Prophet, enabling Muslims to direct their lives and actions in accordance with the directives of their religion,And also to encourageResearch :Islam encourages scientific research and the use of reason in understanding the nature of the universe and God’s signs in it. Muslims are encouraged to study the natural and social s
... Show MoreThe importance of the study stems from the fact that it deals with a very important subject, namely, the pivotal role played by E-banking in achieving the competitive advantage of the banking institutions operating in Algeria. By adopting the banking institution and adopting the elements of the electronic marketing mix and developing it as required by the environment The banking system of developments will inevitably be able to achieve excellence from its competitors as each of these elements have an important role in achieving competitive advantage, we relied in this study on studies and research that directly affect the problem of the study and we have put Estep In order to activate the contribution of e-banking in achieving competitiv
... Show MoreTwo field experiments were conducted during the season 2021-2022 in central Iraq represented by the Al-Muthanna governorate - Al-Majd District and Al-Qadisiyah governorate / Al-Nouriah Research Station to determine the productivity of the Baghdad 3 cultivar from spray foliar fertilization of Macro and Micro elements with alcoholic sugars and half the fertilizer recommendation for addition floor, three treatments were used for fertilization: T1 as the control treatment and T2 with alcoholic sugar fertilization at a concentration of 20 g.L-1 + the fertilizer combination of Macro and Micro elements, and T3 with alcoholic sugar fertilization at a concentration of 40 g.L-1 + the fertilizer combination of Macro and Microelements, at irrigation 55
... Show MoreWe have provided in this research model multi assignment with fuzzy function goal has been to build programming model is correct Integer Programming fogging after removing the case from the objective function data and convert it to real data .Pascal triangular graded mean using Pascal way to the center of the triangular.
The data processing to get rid of the case fogging which is surrounded by using an Excel 2007 either model multi assignment has been used program LNDO to reach the optimal solution, which represents less than what can be from time to accomplish a number of tasks by the number of employees on the specific amount of the Internet, also included a search on some of the
... Show MoreThe research aims to apply a modified SERVQUAL model to evaluate the quality of the educational services via conducting exploratory research for students from the College of Administration and Economics- Department of Business Administration- Evening studies at the University of Baghdad. Questionnaire of two parts was distributed to a sample of (72) students out of (720) students of the 2nd.,3rd. and 4th. year in the beginning of the second semester of the year 2008-2009 to measure the expectations and perceptions to the quality of the educational services. Five major dimensions were analyzed to see the gaps for (22) variables. The study concluded that there were (13) variables confirmed that the
... Show MoreThe diversity of cultures is still the title of an Iraqi specificity that gave the society a diversity and this is reflected in the journalistic reality with the changing of the political system generate a new political and ideological life that differs from what is prevailed during the decades. However, its exacerbation of the degree of division is an additional duty for the press as a cultural platform and a knowledge bridge that contributes to the process of dialogue, addressing the differences, establishing a politically homogeneous structure through the state and socially by uniting all components of society and working to raise public awareness of the importance of national belonging to build a modern state. Cultural diversity is a
... Show MoreThis study was conducted at the Research Experimental Station of the College of Agricultural Engineering/University of Baghdad in the Al-Jadiriyah area during the autumn season of 2022. The study aimed to investigate the effect of phosphorus addition and zinc spraying on the nutrient content and root growth of the cabbage. The experiment included two factors: the first factor was phosphorus with four concentrations (P25%, P50%, P75%, and P100%) of the recommended complete fertilizer dose (135 kg P2O5 per hectare), and the second factor was zinc spraying with three concentrations (0, 30, and 60 mg.L-1) of zinc sulfate (ZnSO4). The results showe
Serial tendering is better than other types of tendering when it comes to cost reduction, where civil infrastructure projects need a significant increase in the amount of tough planning, financial expenditures, engineering work, and resources of a different character than other types of construction projects. The effects of a lack of funding cause decrease in the completion speed of the project on time. The need to reduce the cost of bidding on recurrent civil infrastructure projects is critical. To achieve the desired goals of this research, this article will provide an overview of the type of bids used in the construction of schools implemented in the current financial perspective i
The survey and checklist of invasive species of the insects in some different localities of Iraq are revised; 24 invasive species were documented until December 2018 during the current investigations. The species distributions, common names and synonyms are given.
The current investigation included all of exotic species in Iraq, which are not collected during this study.