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.
The 3D electro-Fenton technique is, due to its high efficiency, one of the technologies suggested to eliminate organic pollutants in wastewater. The type of particle electrode used in the 3D electro-Fenton process is one of the most crucial variables because of its effect on the formation of reactive species and the source of iron ions. The electrolytic cell in the current study consisted of graphite as an anode, carbon fiber (CF) modified with graphene as a cathode, and iron foam particles as a third electrode. A response surface methodology (RSM) approach was used to optimize the 3D electro-Fenton process. The RSM results revealed that the quadratic model has a high R2 of 99.05 %. At 4 g L-1 iron foam particles, time of 5 h, and
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Recording two species of larval cestodes Callitetrarhynchus gracilis and Callitetrarhynchus sp. (Cestoda: Trypanorhyncha) parasitic in body cavity of two carangid fishes (Carangoides malabaricus and Megalaspis cordyla) from north west Arab Gulf, Iraq, is described. The species Callitetrarhynchus sp. was recorded for the first time in Iraq in carangid fishes. Also, two fish species (C. malabaricus and M. cordyla) are considered as new hosts for C. gracilis and Callitetrarhynchus sp. in the Arab Gulf. The cestodes were sent to Prof. Dr. Harry W. Palm, Department of Fisheries Biology, Institute Zoo Morphology, Germany for confirmation of the identification.
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New series of 4,4'-((2-(Aryl)-1H-benzo[d]imidazole-1,3(2H)-diyl)bis(methylene))Diphenol(3a-g) was successfully synthesized from cyclization of the reduction product of bis Schiff bases (2) with aryl aldehydes bearing phenolic hydroxyl in the presence of acetic acid. The structure of these compounds was identified from FT-IR, 1H NMR, 13C NMR and EIMs. The Antioxidant capability was screened by DPPH and FRAP assays. Both assays showed antioxidant capability more than BHT as well. Compounds 3b and 3c showed antioxidant capacity slightly less than ascorbic acid. The docking study for theses compound was carried out as III DNA polymerase inhibitor. The results of docking demonstrated that the increase in hinderances around phenolic hydr
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The research aims for the study about Ibn Tulun's personal and scientific biography to the
scholar, scientist and historian Ibn Tulun Shams Id- Din Mohammad Ibn Ali al-Dimashqi al-
Salihi (953 A.H. / 1546 A.D.) Ibn Tulun was a prominent Muslim historian in Blad al-
Sham.
At the first deals with Ibn Tulun's personal biography, author's name, Lineage, and
nickname, his nativity; his upbringing, and edification, his moral character, Finally, his death.
As to Ibn Tulun's scientific biography, at the first deals with his initiation into education
and learning , sheds light on his tutors and his authorities , scientific stations and travels , his
scholarly status , and Ibn Tulun's alumni or his students .
Abstract Background: The lifestyle of an individual significantly influences health-promoting behaviors. The World Health Organization defines health promotion as a mechanism enabling people to increase control over and improve their health. This study aimed to evaluate the health promoting lifestyle profile of medical staff working in primary health care centers of Al-Rusafa, Baghdad.
The research addresses the feminist lament and its representations in the contemporary Arab theatrical text as one of the purposes of the Arabic poetry and its images, samples, and reasons developed and its incentives multiplied through different time periods in which a dramatic image and representations have been manifested that harmonized with the art of theatre. In order to shed light on these representations, this study has come to look for the representations of lament phenomenon in the Arab theatre texts.
The study consists of an introduction in which the two researchers put forward the research problem, significance and objectives, and a theoretical framework which tackles a theoretical foundation for the research consi
The aim of the research is to identify the trends of Saudi society towards visiting art galleries and museums in light of economic and social transformations after the implementation of the 2030 vision plans. The importance of the research is to track the reasons behind the reluctance of members of society to visit such cultural institutions, and to plan proposals and recommendations for how to attract members of society and motivate them. This research followed the descriptive approach, and the study sample reached 103 members of the Saudi community. several research tools were used in this research such as questionnaire, personal interviews in addition to the researcher notes. The results concluded that the art galleries attract the ap
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New metal ion complexes were synthesized with the general formula; K[PtLCl4], [ReLCl4] and K[ML(Cl)2] where M = Pd(II), Cd(II), Zn(II) and Hg(II), from the Azo ligand (HL) [2-Hydroxy-3-((5-mercapto-1,3,4-thiadiazol-2-yl)diazenyl)-1-naphth aldehyde] (HL) the ligand was synthesized from (2-hydroxy-1-naphthaldehyde) and (5-amino-1,3,4-thiadiazole-2-thiol). The ligand and its metal complexes are characterized by phisco- chemical spectroscopic techniques (FT.IR, UV-Vis and Mass spectra, elemental analysis, molar conductivity, Atomic Absorption, Chloride contain and magnetic susceptibility). The spectral data suggest that the (HL) behaves as a bidentate ligand in all complexes. These studies revealed tetrahedral geometries for all metal complexes
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