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.
Ceremony of the Koran vocabulary animate different connotations unique style patch on
smth not any method of Arabs, has been used used vocabulary and special Madza, he put
every single in place of installation so that if you do not put in place misfire meaning and
became Rkika method. Our goal in this research study a range of vocabulary in terms of the
implications and documenting the trial of the Hadith and sayings of the beneficiaries of Arab
scholars have different attitudes, linguists and interpreters and speakers and fundamentalists,
philosophers, and others.
This research is based on the study of a group of Quranic verses that share a certain part, and these verses are verses of righteousness, and the word righteousness has been mentioned in the Holy Qur’an eight times, and the number of verses in this word was six verses, in four walls, all of which are from the civil fence which is the cow and was There are five words of righteousness contained in them, and the family of Imran is one word, and the table is one word, and the argument is one word. This study adopts the method of analytical interpretation of the Quranic text is a term that means statement and clarification in a way that the researcher produces to divide a Quranic text into its elements that are involved in its formation and
... Show MoreAbstract Political power in Lebanon is a fundamental objective of any political organization, whether political party or political group. Thus, there is a conflict of power. There are two kinds of political conflict that are differentiated by the idea of legitimacy. The competition is in the political system when the agreement between the social forces is considered legitimate, and the conflict is on the political system when the agreement between these forces ceases to be legitimate and Are working to topple it and seek to establish an alternative system. Therefore, the succession of power in Lebanon is a result of the competition and political conflict, which is in turn a result of the large number of regional and international players
... Show MorePraise be to God, who made the pegs of the earth and entrusted them with the task of keeping the earth from tilting, and prayers and peace be upon the one to whom the Qur’an was revealed, Muhammad, and upon his family and all his companions.
The topic of mountains is one of the important topics in human life, as God has associated great miracles with them that indicate the perfection of the power of God Almighty. God Almighty says: (And to the mountains, my palms have turned. This is worthy of every rational person to contemplate His signs, the Almighty, in this solid part and safety belt of the earth, in order to reveal the secrets of the mountains and uncover their treasures. The more the researcher studies the mountains and
... Show MoreFine art represents part of society's culture. The development of art was accompanied by the penetration of new worlds known as the fourth dimension. After art entered the boundaries of geometry and reduction; He began to break into the absurd, and the form and philosophy of art changed, moving from modernity to what came after it to contemporary. Transforming from a formal form into a symbolic form with philosophical implications linked to the light, audio and kinetic effects as they embody time, the concept became the master of the idea. The research aims to identify the concept of time and its types, then the philosophical concept of time and its reflection on contemporary art, through the analytical study of a selection of contempora
... Show MoreIt has mixed views on the concept or the role (Portrait) carving human faces across historical periods. The counting and historical document recording profiles for individual, promised impression represents promised impression represents the importance and greatness of personal without attention logs features and individual features, and in all cases the (portrait) was working for celebrated personality, glorifying and out of respect for his role heroic or reputation or social status.
But if we intend carving human faces one varieties of art in sculpture became necessary for us to proceed from the statement which affirms "The requirement of art to be liberated from their recovery forms as they are in the outside world" and here we beg
Recently, the theory of Complex Networks gives a modern insight into a variety of applications in our life. Complex Networks are used to form complex phenomena into graph-based models that include nodes and edges connecting them. This representation can be analyzed by using network metrics such as node degree, clustering coefficient, path length, closeness, betweenness, density, and diameter, to mention a few. The topology of the complex interconnections of power grids is considered one of the challenges that can be faced in terms of understanding and analyzing them. Therefore, some countries use Complex Networks concepts to model their power grid networks. In this work, the Iraqi Power Grid network (IPG) has been modeled, visua
... Show MoreThis study is based on the basic idea: that human communication does not stop at the limits of words spoken, but extends to include the movements of the body and its members, such as the face, hand, eye, hearing, touch, taste, sensation and the public body.
The human movements represented by polarization, frowns, tattoos, and movements are all auxiliary tools that reach meanings and affect others greatly.
Perhaps their importance is also in their ability to translate what is going on in the soul, and to show it to the outside body members, without the control of the human in many cases, it is thus an important factor in the process of human communication.
The purpose of this study is to show the senses of the senses in the
The research aims to identify the social control among kindergarten department students. In order to achieve the objective of the research, a sample of (400) female students: (200) from Baghdad University / Faculty of Education for women and (200) from Mustansiriyha University / Faculty of Basic Education were chosen randomly.
The researchers designed a tool to measure the social control of the study sample. It was exposed to group of specialists in the educational and psychological sciences, measurement and evaluation. In addition to specialists in kindergartens. Two indicators of validity were used. The Alpha-Cronbach method, Pearson correlation coefficient, and independent samples t-test were used to analyze the c
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