Preferred Language
Articles
/
jbcd-2912
Effect of ageing media on shear bond strength of metal orthodontic brackets bonded with different adhesive systems (A comparative in-vitro study)
...Show More Authors

Background: The aim of this study was to evaluate the shear bond strength (SBS) and adhesive remnant index (ARI) of different orthodontic adhesive systems after exposure to aging media (water storage and acid challenge). Materials and methods: Eighty human upper premolar teeth were extracted for orthodontic purposes and randomly divided into two groups (40 teeth each): the first group in which the bonded teeth were stored in distilled water for 30 days at 37°C, and the second group in which the bonded teeth were subjected to acid challenge. Each group was further subdivided into four subgroups (10 teeth each) according to the type of adhesive system that would be bonded to metal brackets: either non-fluoride releasing adhesive (NFRA), fluoride releasing adhesive (FRA), Fluoride releasing bond with self-etching primer (FRBSP), or powder and liquid orthodontic fluoride releasing adhesive (PLFRA). After 30 days of water storage and acid challenge ageing procedures, the SBS was determined using Instron testing machine with a crosshead speed of 1 mm/min. The ARI was assessed using a stereomicroscope with 10 X magnification. Result: The SBS testing revealed significant differences (p< 0.05) among the four tested adhesive systems in water storage and acid challenge groups using ANOVA F-test. In both groups, the NFRA subgroup exhibited the highest mean SBS value, followed by FRASP, then FRA subgroups, while the PLFRA subgroup had the lowest value of mean SBS. The independent t-test showed non-significant differences in mean SBS values between water storage and acid challenge groups. In respect to the ARI analysis, the Chi-square test showed significant differences among the tested adhesive systems. Conclusion: The shear bond strength of the fluoride releasing adhesive system was less than that of the non-fluoride releasing adhesive system, but still above the clinically acceptable range.

 

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Dec 17 2017
Journal Name
Al-khwarizmi Engineering Journal
Effect of Nano Powder on Mechanical and Physical Properties of Glass Fiber Reinforced Epoxy Composite
...Show More Authors

Fiber reinforced polymer composite is an important material for structural application. The diversified application of FRP composite has taken center of attraction for interdisciplinary research. However, improvements on mechanical properties of this class of materials are still under research for different applications. In this paper we have modified the epoxy matrix by Al2O3, SiO2 and TiO2 nano particles in glass fiber/epoxy composite to improve the mechanical and physical properties. The composites are fabricated by hand lay-up method. It is observed that mechanical properties like flexural strength, hardness are more in case of SiO2 modified epoxy composite compare to other nano

... Show More
View Publication Preview PDF
Publication Date
Fri Jun 01 2018
Journal Name
Journal Of Engineering Science And Technology
Effect of cooling mode on serviceability of partially prestressed-concrete beams exposed to fire flame
...Show More Authors

Preview PDF
Scopus
Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
The effect of current density on the structures and photoluminescence of n-type porous silicon
...Show More Authors

Porous silicon (PS) layers were formed on n-type silicon (Si) wafers using Photo- electrochemical Etching technique (PEC) was used to produce porous silicon for n-type with orientation of (111). The effects of current density were investigated at: (10, 20, 30, 40, and50) mA/cm2 with etching time: 10min. X-ray diffraction studies showed distinct variations between the fresh silicon surface and the synthesized porous silicon. The maximum crystal size of Porous Silicon is (33.9nm) and minimum is (2.6nm) The Atomic force microscopy (AFM) analysis and Field Emission Scanning Electron Microscope (FESEM) were used to study the morphology of porous silicon layer. AFM results showed that root mean square (RMS) of roughness and the grain size of p

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 12 2020
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability
The effect of doping process on the structural and optical properties of Ag2Se thin films.
...Show More Authors

Preview PDF
Publication Date
Wed May 10 2023
Journal Name
Journal Of Planner And Development
The effect of urban obsolescence on the quality of the built environment for historical quarters
...Show More Authors

             The centers of cities and historical quarter are exposed to a severe threat to the values of the physical and legal urban environment as a result of the value deterioration and the emergence, emergence and spread of new values on the intellectual and urban context, which generates the loss of the urban environment for its spatio-temporal continuity, flexibility, adaptation and continuity, and thus urban obsolescence, Hence the problem of the research in “the lack of comprehensiveness of studies on the phenomenon of urban obsolescence and its impact on the decline in the values of the quality of the built environment in historic

... Show More
View Publication Preview PDF
Publication Date
Tue Jul 14 2015
Journal Name
Ibn Al-haitham J. For Pure & Appl. Sci.
Effect of Annealing Temperature and Thickness on the Structural and Optical Properties of CdSeThin Films
...Show More Authors

CdSe alloy has been prepared successfully from its high purity elements. Thin films of this alloy with different thicknesses (300,700)nm have been grown on glass substrates at room temperature under very low pressure (10-5)Torr with rate of deposition (1.7)nm/sec by thermal evaporation technique, after that these thin films have been heat treated under low pressure (10-2)Torr at (473,673)K for one hour. X-ray patterns showed that both CdSe alloy and thin films are polycrystalline and have the hexagonal structure with preferential orientation in the [100] and [002] direction respectively. The optical measurements indicated that CdSe thin films have allowed direct optical energy band gap, and it increases from (1.77- 1.84) eV and from

... Show More
Publication Date
Mon Nov 24 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of disinfectant agents on certain physical and mechanical properties of type IV dental stone
...Show More Authors

Background: Dental stone casts come into contact with impression materials and becomes susceptible to cross contamination from saliva and blood. This study was done to evaluate the physical and mechanical properties of dental stone type IV after treatments with various disinfecting agents and regimes (methods). Materials and Methods: Type IV dental stone and different types of disinfecting agents were used and divided into seven groups: G1: dental stone without disinfection (control group), G2: dental stone mixed with silver nitrate powder 0.5% , G3: dental stone mixed with silver nitrate powder 1%, G4: dental stone mixed with copper sulfate powder 0.5%, G5: dental stone mixed with copper sulfate powder 1% ,G6: dental stone immersed in prop

... Show More
View Publication Preview PDF
Publication Date
Tue May 01 2012
Journal Name
Iraqi Journal Of Physics
Studying the effect of temperature and treating time on some physical properties of carbon black
...Show More Authors

Samples prepared by using carbon black as a filler material and phenolic resin as a binder. The samples were pressed in a (3) cm diameter cylindrical die to (250)MPa and treated thermally within temperature range of (600-1000)oC for two and three hours. Physical properties tests were performed, like density, porosity, and X-ray tests. Moreover vicker microhardness and electric resistivity tests were done. From the results, it can be concluded that density was increased while porosity was decreased gradually with increasing temperature and treating time. In microhardness test, it found that more temperature and treating time cause more hardness. Finally the resistivity was decreased in steps with temperature and treating time. It can be c

... Show More
View Publication Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees21gr
Effect of cold atmospheric plasma on the wound of diabetic rats by FE-DBD system
...Show More Authors

This study explains the effect of non-thermal (cold) plasma on wound of diabetic rats by (FE-DBD) system, 3cm probe diameter is used. The output power was ranged from (12-20) W. The effect of non-thermal plasma on wounds of a diabetic was observed with different exposure durations (20,30) sec., the plasma exposure duration decreases the sugar level in blood and the diameter of the wound. These results indicate the cold plasma can be used to enhance the insulin level (i.e., blood sugar) and wounds treatment.

View Publication
Scopus Crossref
Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Effect of Al2O3 Particles and Precipitation Hardening on the Properties of Cast 332 Aluminum Alloy
...Show More Authors

In this work, 332 Al alloy was prepared and reinforced with (0.5% and 1%) nano-Al2O3 particles. The prepared unreinforced and reinforced 332 Al alloy with nano-Al2O3 were solution heat treated (T6) at 510 ̊C and aged at 225 ̊C with different times (1, 3, and 5 h). Hardness test was performed on all the prepared alloys. All prepared alloys were dry slided under different applied loads (5, 10, 15, and 20 N) against steel counterface surface using pin on disk apparatus. The results showed that refinement effect was observed after addition of nano-Al2O3 particles and a change in silicon morphology after performing the solution heat treatment. The results also showed that har

... Show More
View Publication Preview PDF
Crossref (3)
Crossref