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.
The researcher dealt with the importance of striking proverbs in the Holy Qur’an and their uses and benefits in Islamic education and ethics and between the types of proverbs, so it emerged through the study the following things that the proverbs are of three types: authorized, latent, and transmitted, and it has been shown through the current study that the proverb has conditions that the proverb is not valid except There are five: (realism, clarity, environmental, meaning injury, and good pronunciation). If the example violates these conditions, it is not an example. This study showed that proverbs have a prominent role in persuasion, argument, statement, education, clarity, approximation, education, refinement, correct belief, etc.
... Show MoreThe media plays an important role in a number of functions performed by them. Press is one of those media which had and still have a clear role in addressing the various issues, topics, and events. Journalism is no longer as expressed by owners of the liberal theory – it seeks to raise the instincts – but it began to excite the minds of readers to meet their needs. At the same time, it does not neglect the search for the truth and work to deliver it to readers. Some have identified a set of tasks carried out by the press including the interest in public affairs, the needs of the community, work to provide happiness, what is beneficial and useful and combat the negative phenomenon and to address the deviations facing society. The comi
... Show MorePsychology is one of the sciences that consciously overlap in terms of mutual influence with art forms in general and cinematic arts in particular. The psychological effect can be extrapolated into the visual image through the characters and their actions, especially the adoption of psychoanalytic ideas and proposals that came by (Freud), The cinema benefited from the concepts of psychology and participated in the process of creativity and the manufacture of events or the actions of characters, such as the concepts of consciousness and subconsciousness to express the psychological dimension of the film events, these data can be counted on the level of nightmares in the cinematic movies.
The methodological framework included the rese
The Collapse of the Dreams in Ayad Akhtar’s Disgraced (2012) is a study that examines the theme of shattered dreams within the context of the play. Focusing on the protagonist Amir Kapoor, a successful Pakistani-American lawyer, and his journey from assimilation to self-discovery. This study explores the consequences of denying one's cultural heritage and the disintegration of personal aspirations. Through a close analysis of Amir's interactions with his wife, friends, and colleagues. This research investigates the underlying factors that contribute to the collapse of dreams and the unraveling of identity. By employing literary analysis and cultural criticism, the research sheds light on the complexities of cultural assimilation, racial i
... Show MoreHardly a society is devoid of manifestations of imitating the opposite sex with the disparity between societies in quantity and quality, as imitating the opposite sex is an old phenomenon, and whoever follows what the old researchers wrote on this subject, finds various sayings, some of which lack evidence, being a kind of guesswork, A generalization that is not based on what is evidenced by it, and others consider resemblance to a behavior in which an animal resembles a human being. I will highlight in this research the resemblance to the opposite sex in the cultures of peoples, making the study into three sections. The manifestations of resembling men and women spread in Greek society greatly, and then the second study was devoted to the
... Show MoreThis Study is Concerned with (the debate of democracy in the modern islamic political thought ) which discovers the attitudes and this trend of thought so-called democracy . Therefore this study is divided into three sections : the first section is concerned with the democracy in extremist Islamic speech, the second section tackles appropriation of democracy in moderate Islamic speech , while the third section is concerned with the democracy in Aistighrabi Islamic speech . Finally the conclusion sums up the findings of the study
Objective: This study aims to analyze the role of the People's Republic of China in the 1955 Bandung Conference and assess its contributions to international cooperation and peace. It specifically examines how China's participation aligns with the United Nations Sustainable Development Goals (SDGs), particularly Goal 16. Theoretical Framework: The research is grounded in a structuralist approach to international relations, focusing on the agency of developing nations in shaping a post-colonial global order. It considers concepts such as peaceful coexistence, national sovereignty, and South-South cooperation. Method: A historical-analytical method is employed, tracing China’s diplomatic trajectory from the 1954 Colombo and Bo
... Show Moreكانت وسائل الاعلام- التقليدية والحديثة – وستبقى وسيلة مهمة لتدفق المعلومات والتعبير عن المشاعر ووصف الاحداث وتشكيل الرأي العام المحلي والدولي عن مختلف القضايا التي تهم الافراد والمجتمعات وفي مقدمتها قضايا العنف بمستوياته كافة ،والتطرف الديني والارهاب بكل مسمياته وستحاول هذه الدراسة ان تقدم اجابات عن اسئلة محددة تمثل الاطار النظري لدراسات مسحية ترصد النظريات التي ترسم الاطر النظرية الت
... Show MoreThe research aims:
1- To know the intemperance use of the internet by the University's students.
2- To know the differences with a statistical indication in the intemperance use of the internet after the gender's inconstant ( Males-females).
3- To know the differences with a statistical indication in the intemperance use of the internet after the Major's inconstant ( scientific- humanistic)
This current research restricts a sample of the university students for both sexes.
Theoretical frame:
The research viewed several theories that explains intemperance use of the internet & the results.
Research measures :
1- Research has been adapted the scale ( Internet use) which was prepared by the Moroccan researcher (