Preferred Language
Articles
/
alkej-449
Effect of Laser Shock Peening on the Fatigue Behavior and Mechanical Properties of Composite Materials
...Show More Authors

In this study, Laser Shock Peening (LSP) effect on the polymeric composite materials has been investigated experimentally. Polymeric composite materials are widely used because they are easy to fabricate and have many attractive features. Unsaturated polyester resin as a matrix was selected and Aluminum powder with micro particles as a reinforcement material was used with different volume fraction (2.5%, 5% and 7.5%). Hand lay-up process was used for preparation the composites. Fatigue test with constant amplitude with stress ratio (R =-1) was carried out before and after LSP process with two levels of energy (1Joule and 2Joule). The result showed an increase in the endurance strength of 25.448% at 7.5% volume fraction when peened is 1J laser energy. Also, the ultimate strength and Young’s modulus were increased by 6.474% and 10.588% respectively after LSP with the same laser energy.  On the other hand, composites with (2.5% and 5%) volume fraction manifested a reduction in the mechanical and fatigue strength especially when treated by 2J laser energy.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Jun 19 2023
Journal Name
Journal Of Engineering
Study of Some Mechanical Properties for a Polymer Material Reinforcement with Chip or Powder Copper
...Show More Authors

In this paper, chip and powder copper are used as reinforcing phase in polyester matrix to form composites. Mechanical properties such as flexural strength and impact test of polymer reinforcement copper (powder and chip) were done, the maximum flexural strength for the polymer reinforcement with copper (powder and chip) are (85.13 Mpa) and (50.08 Mpa) respectively was obtained, while the maximum observation energy of the impact test for the polymer reinforcement with copper (powder and chip) are (0.85 J) and (0.4 J) respectively  

View Publication Preview PDF
Crossref
Publication Date
Sun Oct 02 2011
Journal Name
Journal Of Educational And Psychological Researches
The Effect of a consulting program for decreasing withdrawal behavior of the children with autism of kindergarten
...Show More Authors

       unacceptable social behaviors, particularly withdrawal behavior that appears in children with autism represent a major problem hindering the process of communication with those around them and therefore the process of mergence  with them be difficult.

     The withdrawal causes a real affect deficit for children with autism limits the possibility of development of their intellectual and mental growth due to their solitude and the weakness of their focus in the acquisition of pedagogical skills and lack the necessary social skills to maintain the relations of friendship and enjoyment of them.

      withdrawal children fail to participate

... Show More
View Publication Preview PDF
Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Video Games on Intermediate Students’ Academic Achievement
...Show More Authors

The study attempts to identify 1) the habits of playing video games among students, 2) the effect of playing video games on students’ academic achievement, 3) the statistically significant differences among students in regard of (gender, time of playing video games, number of hours). To this end, a five-likert scale questionnaire included four questions was applied to (250) male and female students chosen randomly from the second-intermediate stage at Al-Karakh side secondary schools. The findings revealed that students play games only on holidays and less than an hour daily, which means playing games does not affect their academic achievement. Additionally, the findings found there is a significant difference between male and female i

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 30 2016
Journal Name
College Of Islamic Sciences
The conversations of reason and thinking as stated in the Sunnah and its impact on human behavior
...Show More Authors

The Sunnah of the Prophet has a great impact in building human behavior, and the formation of Islamic thought, has worked to spread science in all of Egypt, as it carried to the people of the eternal prophecy of the love of science, it was a source of knowledge and civilization. It is a generous source, a rich source of the Islamic nation, always tender, and renewed benefit, which is not only a source of legislation and language but is a source of guidance for thought and guidance of behavior, and the Hadith The importance is obvious In the integration of Islam, and show aspects of human integration in the personality of Mustafa , and the Muslims are interested in talking - collected and codification -, and made the effort of the cent

... Show More
View Publication Preview PDF
Publication Date
Tue Apr 04 2017
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
EFFET OF SOME ISOLATION FROM FUGI BAGHDAD HOSPITAL ON PHYSIOLOGY OF LIVER, KIDNEY AND TESTIS IN ALBINO MALE MICE.: EFFET OF SOME ISOLATION FROM FUGI BAGHDAD HOSPITAL ON PHYSIOLOGY OF LIVER, KIDNEY AND TESTIS IN ALBINO MALE MICE.
...Show More Authors

Some types of the fungus Aspergillus were isolated from some hospitals in the city of Baghdad (Imam Ali Hospital and Sadr General Hospital). The samples were taken by Transport media at a rate of three replicates of each place isolated from samples from different places within the hospital (waste, baths, the sick beds, corridors and room floors) for the purpose of isolating and diagnosing the fungus on the Czapeck Dox Agar media. It was noticed that the spread rate of fungus Aspergillus was 70% compared to other species that have emerged during the isolation process of the Sabouraud's Dextrose Agar media. The species A.niger (56.25%) was considered the most common type of fungus visible during the isolation process of the Imam Ali Hospit

... Show More
View Publication Preview PDF
Publication Date
Sun Sep 20 2026
Journal Name
Journal Of Baghdad College Of Dentistry
An Evaluation of Some Mechanical Properties of Autopolymerizing Acrylic Resin with the Modified One after Changing the Curing Environment: (In vitro Study)
...Show More Authors

Background: Studying and investigating the transverse strength(Ts), impact strength(Is), hardness (Hr) and surface roughness(Ra) of conventional and modified autopolymerizing acrylic resin with different weight percentages of biopolymer kraftlignin, after curing in different water temperatures; 40°C and 80°C. Material and Methods: Standard acrylic specimens were fabricated according to ADA specification No.12 for transverse strength, ISO 179 was used for impact testing, Shore D for hardness and profilometerfor surface roughness. The material lignin first dispersed in the monomer, then the powder PMMA is immediately added. Ligninadded in different weight percentages. Then cured using pressure pot (Ivomet) in two temperatures;40°C a

... Show More
View Publication Preview PDF
Publication Date
Tue Oct 02 2018
Journal Name
Iraqi Journal Of Physics
Gas sensitivity properties of TiO2/Ag nanocomposite films prepared by pulse laser deposition
...Show More Authors

In this study, a double frequency Q-switching Nd:YAG laser beam (1064 nm and λ= 532 nm, repetition rate 6 Hz and the pulse duration 10ns) have been used, to deposit TiO2 pure and nanocomposites thin films with noble metal (Ag) at various concentration ratios of (0, 10, 20, 30, 40 and 50 wt.%) on glass and p-Si wafer (111) substrates using Pulse Laser Deposition (PLD) technique. Many growth parameters have been considered to specify the optimum condition, namely substrate temperature (300˚C), oxygen pressure (2.8×10-4 mbar), laser energy (700) mJ and the number of laser shots was 400 pulses with thickness of about 170 nm. The surface morphology of the thin films has been studied by using atomic force microscopes (AFM). The Root Mean Sq

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
The Effect of Thickness on Some Optical Properties of Sb2S3 Thin Films Prepared by Chemical Bath Deposition
...Show More Authors

Sb2S3 thin films have been prepared by chemical bath deposition on a glas sub Absorbance and transmittance spectra were recorded in the wavelength range (30-900) nm. The effects of thickness on absorption coefficient, reflectance, refractive index, extinction coefficient, real and imaginary parts of dielectric constant were estimated. It was found that the reflectivity, absorption coefficient , extinction coefficient, real part of dielectric constant and refractive index, all these parameters decrease as the thickness increased, while the imaginary part of the dielectric constant increase as the thickness incre

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Tue Jun 01 2021
Journal Name
Iraqi Journal Of Physics
Effect of Transition Metal Dopant on the Electrical Properties of ZnO-TiO2 Films Prepared by PLD Technique
...Show More Authors

In this article, the influence of group nano transition metal oxides such as {(MnO2), (Fe2O3) and (CuO)} thin films on the (ZnO-TiO2) electric characteristics have been analyzed. The prepared films deposited on glass substrate laser Nd-YAG with wavelength (ℷ =1064 nm) ,energy of (800mJ) and number of shots (400). The density of the film was found to be (200 nm) at room temperature (RT) and annealing temperature (573K).Using DC Conductivity and Hall Effect, we obtained the electrical properties of the films. The DC Conductivity shows that that the activation energies decrease while the σRT at annealing temperature with different elements increases the formation of mixed oxides. The Hall effect, the elec

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Dec 03 2017
Journal Name
Baghdad Science Journal
Effect of Diffusion Temperature on the some Electrical Properties of CdS:In Thin Films Prepared by Vacuum Evaporation
...Show More Authors

CdS films were prepared by thermal evaporation technique at thickness 1 µm on glass substrates and these films were doped with indium (3%) by thermal diffusion method. The electrical properties of these have been investigated in the range of diffusion temperature (473-623 K)> Activation energy is increased with diffusion temperature unless at 623 K activation energy had been decreased. Hall effect results have shown that all the films n-type except at 573 and 623 K and with increase diffusion temperature both of concentration and mobility carriers were increased.

View Publication Preview PDF
Scopus Crossref