Preferred Language
Articles
/
jbcd-638
Evaluation of shear bond strength of zirconia to tooth structure after different zirconia surface treatment techniques
...Show More Authors

Background: This study aimed to evaluate the effect of zirconia different surface treatments (primer, sandblast with 50μmAl2O3, Er,Cr:YSGG laser) on shear bond strength between zirconia surface and resin cement. Material and methods: Sixty presintered Y-TZP zirconia cylinder specimens (IPS e.max ZirCAD, Ivoclar vivadent) will be fabricated and sintered in high temperature furnace of (1500 C for 8 hours) according to manufacturer’s instructions to the selected size and shape of (5mm. in diameter and 6mm in height). All specimens were ground flat using 600.800.1000.1200, aluminum oxide abrasive paper to obtain a standardized surface roughness. Surface roughness values were then recorded in µm using surface roughness tester (profilometer) to obtain a standardized data base line for all samples. The specimens were then randomly divided into three main groups (n=20); group A: no surface treatment (control group), group B: specimens in this group treated with 50μm Al2O3 and group C: specimens in this group treated with Er,Cr:YSGG laser. Sixty sound human premolars were used in this study, after construction of acrylic blocks, the occlusal surface of the teeth were ground flat, with diamond cutting disk to obtain a flat dentine surface . Prior to cementation of zirconia cylinders to tooth specimens subgroups (A1,B1,C1) will receive a coat of metal/zirconia primer and left to react for three minutes, while the subgroups (A2,B2,C2) were left undisturbed. Bonding surface of zirconia cylinder was then luted with SpeedCEM self adhesive resin cement under a static load of 2Kg. placed on the vertical arm of the surveyor and allowed to auto cure for 4minutes.The final cemented specimens were then stored in distilled water at room temperature for 24hours. All specimens were subjected to shear loading force in a universal testing machine at crosshead speed of 1mm/min. The shear bond strength values were analyzed statistically with one-way ANOVA; the fractured surfaces of zirconia cylinders were examined with a stereo-microscope to observe the failure mode. Results: The air borne-particle of 50μm followed by primer application showed significantly the higher bond strength than other groups. Conclusion : Within the limitation of this study, the results showed that sandblasting the bonding surface of zirconium cylinders with 50μmAl2O3 produced the highest values of shear bond strength , also the use of primer enhanced shear bond strength as well. Keyword: zirconia surface treatments, shear bond strength.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jan 01 2019
Journal Name
Energy Procedia
Synthesis and Study the Structure, electrical and optical properties of Bi2-xCdxSr2Ca2Cu3O10+ δ thin film Superconductors
...Show More Authors

View Publication
Scopus (12)
Crossref (11)
Scopus Clarivate Crossref
Publication Date
Mon Sep 30 2024
Journal Name
Iraqi Journal Of Science
Overlapping Structure Detection in Protein-Protein Interaction Networks Using a Modified Version of Particle Swarm Optimization
...Show More Authors

In today's world, the science of bioinformatics is developing rapidly, especially with regard to the analysis and study of biological networks. Scientists have used various nature-inspired algorithms to find protein complexes in protein-protein interaction (PPI) networks. These networks help scientists guess the molecular function of unknown proteins and show how cells work regularly. It is very common in PPI networks for a protein to participate in multiple functions and belong to many complexes, and as a result, complexes may overlap in the PPI networks. However, developing an efficient and reliable method to address the problem of detecting overlapping protein complexes remains a challenge since it is considered a complex and har

... Show More
View Publication
Scopus Crossref
Publication Date
Mon Mar 25 2019
Journal Name
Al-academy
Working of the Secondary Event Structure in Embodying the Film Unity: ماهر مجيد ابراهيم - شروق مالك
...Show More Authors

The topic of the working of the secondary event structure in the embodiment of the film unity is related to the ability to produce a film of controlled events that strengthen each other. The researchers divided the subject topic into an introduction and two sections, as follows: The first section is the event and the action in drama construction wherein the relationship of the dramatic act with the events in general and the secondary event in particular were studied as it has a relationship in a synergistic building of the film unity.

The second section was the patterns of the secondary event in the film wherein the researchers dealt with the patterns, types and functions

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
The formation, structure, and electronic properties of Lansoprazol drug and cucurbit [7]urils complex (Theoretical Study)
...Show More Authors

The current study deals with host-guest complex formation between cucurbit [7] urils as host and lansoprazole as guesti using PM3 (semi empirical molecules orbital calculations) also DFT calculations. In this complex, the formation of hydrogen bonding may be occurred through portal oxygen atoms(O2) of cucurbit [7] urils and amine groups (NH 2 )of the drug. The energies of HOMO and LUMO orbital’s have been computed for the host guest complex and its components. The result of the stabilization energy explained a complex formation.

View Publication Preview PDF
Crossref
Publication Date
Mon Jun 05 2023
Journal Name
Communications In Mathematical Biology And Neuroscience
THE DYNAMICS OF A STAGE-STRUCTURE PREY-PREDATOR MODEL WITH HUNTING COOPERATION AND ANTI-PREDATOR BEHAVIOR
...Show More Authors

The mathematical construction of an ecological model with a prey-predator relationship was done. It presumed that the prey consisted of a stage structure of juveniles and adults. While the adult prey species had the power to fight off the predator, the predator, and juvenile prey worked together to hunt them. Additionally, the effect of the harvest was considered on the prey. All the solution’s properties were discussed. All potential equilibrium points' local stability was tested. The prerequisites for persistence were established. Global stability was investigated using Lyapunov methods. It was found that the system underwent a saddle-node bifurcation near the coexistence equilibrium point while exhibiting a transcritical bifurcation

... Show More
View Publication
Scopus (10)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Journal Of Ovonic Research
Study structure and optical properties of Ag2Se, Ag2Se0. 8Te0. 2 and Ag2Se0. 8S0. 2 thin films
...Show More Authors

Silver sulfide and the thin films Ag2Se0.8Te0.2 and Ag2Se0.8S0.2 created by the thermal evaporation process on glass with a thickness of 350 nm were examined for their structural and optical properties. These films were made at a temperature of 300 K. According to the X-ray diffraction investigation, the films are polycrystalline and have an initial orthorhombic phase. Using X-ray diffraction research, the crystallization orientations of Ag2Se and Ag2Se0.8Te0.2 & Ag2Se0.8S0.2 (23.304, 49.91) were discovered (XRD). As (Ag2Se and Ag2Se0.8Te0.2 & Ag2Se0.8S0.2) absorption coefficient fell from (470-774) nm, the optical band gap increased (2.15 & 2 & 2.25eV). For instance, the characteristics of thin films made of Ag2Se0.8Te0.2 and Ag2Se0.8S0.2

... Show More
Publication Date
Fri Dec 20 2024
Journal Name
Iraqi Journal Of Pharmaceutical Sciences
Sulfur Derivatives of 1,2,4-Triazole: Recently Developed Compounds, Structure Activity Relationship, and Biological Activity: Review article
...Show More Authors

The term of heterocyclic chemistry focuses only on heterocyclic compounds, which consider as a percentage of organic chemistry, they equal to greater than sixty-five. These compounds are widely founded in nature and most of them are important to life. In the past few years, scientist fused on 1,2,4-triazoles and their condensed heterocyclic ring due to their medicinal significance, 1,2,4-triazole containing Sulphur atom is one of the important heterocyclic moieties due to its broad range of biological activities also their derivatives can accommodate one of the alternatives as electronic effect as exchanges of the electronic density (electron donating or withdrawing) groups ; for all what mentioned above they are consider as a core

... Show More
View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Sat Jan 01 2022
Journal Name
Latin American Journal Of Solids And Structures
Peak Ground Acceleration Models Predictions Utilizing Two Metaheuristic Optimization Techniques
...Show More Authors

Scopus (15)
Crossref (15)
Scopus Clarivate Crossref
Publication Date
Sat Jan 01 2022
Journal Name
Latin American Journal Of Solids And Structures
Peak Ground Acceleration Models Predictions Utilizing Two Metaheuristic Optimization Techniques
...Show More Authors

View Publication
Crossref (15)
Crossref
Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Hiding Techniques for Dynamic Encryption Text based on Corner Point
...Show More Authors

Hiding technique for dynamic encryption text using encoding table and symmetric encryption method (AES algorithm) is presented in this paper. The encoding table is generated dynamically from MSB of the cover image points that used as the first phase of encryption. The Harris corner point algorithm is applied on cover image to generate the corner points which are used to generate dynamic AES key to second phase of text encryption. The embedded process in the LSB for the image pixels except the Harris corner points for more robust. Experimental results have demonstrated that the proposed scheme have embedding quality, error-free text recovery, and high value in PSNR.

View Publication Preview PDF
Scopus (11)
Crossref (3)
Scopus Clarivate Crossref