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.
Polyaniline nanofibers (PAni-NFs) have been synthesized under various concentrations (0.12, 0.16, and 0.2 g/l) of aniline and different times (2h and 3 h) by hydrothermal method at 90°C. Was conducted with the use of X-ray diffraction (XRD), Fourier Transform Infrared spectra (FTIR), Ultraviolet-Visible (UV-VIS) absorption spectra, Thermogravimetric Analysis (TGA), and Field Emission-Scanning Electron Microscopy (FE-SEM). The X-ray diffraction patterns revealed the amorphous nature of all the produced samples. FE-SEM demonstrated that Polyaniline has a nanofiber-like structure. The observed typical peaks of PAni were (1580, 1300-1240, and 821 cm-1 ), analyzed by the chemical bonding of the formed PAni through FTIR spectroscopy. Also, tests
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Abstract
The main question raised in this paper is: Is it possible to translate the ‘genre’
of Quran? And if this ‘genre’ is Quran specific, a ‘genre’ of its own, i.e. a unique one,
how can the Quranic text be translated from Arabic into English or any other
language? This question has been raising a lot of controversy among translation
theorists, linguists, philosophers and scholars of Islam and specialists in the sciences
of Arabic language let alone Quran exegetes. Scholars of the Arabic language and
scholars of Islam have argued that because of the genre of Quran is the genre of (ijaz),
translatability can never be possible. Equivalence, thus, cannot be achieved especially
if we know that so far
Abstract:
It is essential to provide health care directly or indirectly based on laboratory tests in order of diagnosing diseases. There is an urgent need for the results of such tests to be accurate and reliable. Therefore, the International Organization for Standardization has prepared special standards for medical laboratories to prove their efficiency, presented in standards 15189: 2012. The aim of the research is to determine the possibility of the Al-alwiya Women's Hospital in meeting the requirements of the standards 15189: 2012, which includes administrative requirements consisting of fifteen items and technical requirements consisting of ten items. The research is important because laboratories shou
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The character table or the table of eigen values for the D7h point group, which is not found in the literature was constructed. The constructed table is used to classify all modes of the vibrational frequencies of the IR and Raman spectra for any compound or molecule that has the D7h symmetry in the Point Group. For that, it was used for classifying all the modes of vibrational frequencies of the [7] cyclacene (linear) monitoring molecule, possessing D7h symmetry. The constructed table was used to classify the symmetry species for the total degrees of freedom, total degrees of transition, total degrees of rotation and for the total degrees of modes of vibration (3N-6) for this tube. The character table wa
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Discussion dealt with the independent factors critical such us success factors and the risk management process, and dependent factor of the general competitive strategies, and began searching the dilemma of thought, as crystallized his problem in the light of the need for organizations to philosophy and deeper vision of a more comprehensive understanding of the concept of risk management, assessment and management to maximize the competitive strategies of public, and on this basis, Search queries formulated problem of the gap between the knowledge-based intellectual propositions farcical for the purposes of interpretation of the relationship between the critical success factors and the risk
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The study aimed at identifying the role of the Faculty of Education in the community service in light of vision of the Kingdom 2030 from the faculty members’ point of view at the University of Jeddah. The study used a descriptive method through a questionnaire administered to a sample of the faculty members.It concluded that the role of the College in serving the community is the development of the right habits in the family and the importance of establishing bridges of cooperation between the Faculty of Education and the surrounding environment and teaching special education teachers how to apply some methods of measurement to determine the needs of students with disabilities. The results also pointed out that there are no statistical
... Show MoreThe research aims to show the relationship between the use of automated accounting systems technology and its impact on enhancing the efficiency and effectiveness of the internal control system in a sample of Bahraini universities in light of the rapid changes in the electronic business environment. Automated accounting and its impact on enhancing the efficiency and effectiveness of the internal control system, and it is concluded through the analytical study of the research sample that there is a percenta
... Show MoreThis research was distributed into two sections, the first section was concerned with the concept of value for De Saussair and its methodological impact on his linguistic structural conceptions with respect of the distinction between synchronism and diachronism, the value role of linking function between the sounds and the though, the basing of his theoretical conception on the language being a form and not a material according to this principle and the value impact on the demonstration that the linguistic element acquires its functional importance from the relations inside the language system. It also stopped at the methodological impact of value on defining the analytical linguistic unit and the value role in semantics through the prin
... Show MoreThe aim of this study was Identifying the relation of coordination and kinesthetic perception with artistic performance level in gymnastics skills for students in second class from the college of physical education/ university of Baghdad/ Al - jadreia .The searchers have been used the descriptive method in scanning style .The subject of this search has been taken (45) female - student in second class from the college of physical education/ university of Baghdad . The searchers have reached into specific conclusions concerning with statistic analysis about immoral joint relation between sensitive- kinetic coincidence and realization and with Artistic Performance Level in Gymnastics Skills for Women for second class .The an important recommen
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