Preferred Language
Articles
/
alkej-519
Investigation of Thermal Stress Distribution in Laser Spot Welding Process
...Show More Authors

The objective of this paper was to study the laser spot welding process of low carbon steel sheet. The investigations were based on analytical and finite element analyses. The analytical analysis was focused on a consistent set of equations representing interaction of the laser beam with materials. The numerical analysis based on 3-D finite element analysis of heat flow during laser spot welding taken into account the temperature dependence of the physical properties and latent heat of transformations using ANSYS code V.10.0 to simulate the laser welding process. The effect of laser operating parameters on the results of the temperature profile were studied in addition to the effect on thermal stresses  and dimensions of the laser welded workpiece which showed good correlations between analytical and numerical results. It was found that the temperature gradients during laser welding are usually very large and it was viewed that very high temperature at the center of the workpiece, and is decreased very significantly as propagating along the radial direction. Also it found that the thermal residual stresses around the laser spot due to plastic strains were very small and localized within 1.0 mm range. It is concluded that the laser welding process is effective to reduce the welding residual stress. The stresses along the lateral direction of the workpiece changed from compression at the spot under the laser beam and tension away from the spot at the end of welding to tension at the spot under the laser beam and compression away from the spot when it cooled, which are in a good agreement with the published results.

   

View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Sep 08 2022
Journal Name
Al-khwarizmi Engineering Journal
Performance Prediction in EDM Process for Al 6061 Alloy Using Response Surface Methodology and Genetic Algorithm
...Show More Authors

The Electric Discharge (EDM) method is a novel thermoelectric manufacturing technique in which materials are removed by a controlled spark erosion process between two electrodes immersed in a dielectric medium. Because of the difficulties of EDM, determining the optimum cutting parameters to improve cutting performance is extremely tough. As a result, optimizing operating parameters is a critical processing step, particularly for non-traditional machining process like EDM. Adequate selection of processing parameters for the EDM process does not provide ideal conditions, due to the unpredictable processing time required for a given function. Models of Multiple Regression and Genetic Algorithm are considered as effective methods for determ

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Thu Dec 01 2022
Journal Name
Journal Of Engineering
The Effectiveness of a Simulation Model of Thermal Insulation in Building Materials Using Cellulose Extracted from Agricultural Waste in Baghdad
...Show More Authors

This study found that one of the constructive, necessary, beneficial, most effective, and cost-effective ways to meet the great challenge of rising energy prices is to develop and improve energy quality and efficiency. The process of improving the quality of energy and its means has been carried out in many buildings and around the world. It was found that the thermal insulation process in buildings and educational facilities has become the primary tool for improving energy efficiency, enabling us to improve and develop the internal thermal environment quality processes recommended for users (student - teacher). An excellent and essential empirical study has been conducted to calculate the fundamental values ​​of the

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Mon Oct 01 2018
Journal Name
Plant Archives
Effect of salinity stress and selenium spraying on broad bean plant Vicia faba L.
...Show More Authors

The experiment was conducted in the old botanical garden belong to Biology Department/ College of Education for Pure Science - Ibn Al-Haitham/Baghdad University for growing season 2015-2016 to study the effect of irrigation with four concentrations of sodium chloride (0, 50, 100, 150) mM.L-1 and spraying with selenium in three concentrations (0, 10, 20) mgL-1 on growth of broad bean plant using clay pots. The experiment was design according to completely randomized design (CRD) with three replications. Results indicated that broad bean plant irrigated with saline water and increasing concentrations of sodium chloride in growth medium caused a significant decreased in the plant growth parameters (plant height, no. of compound leaves. Plant-1

... Show More
Preview PDF
Scopus (1)
Scopus
Publication Date
Mon Aug 22 2022
Journal Name
Biochemical And Cellular Archives
Measurement of inflammation and oxidative stress biomarkers induced by cigarette smoke among Iraqi smokers.
...Show More Authors

To determine the association between cigarette smoking and oxidative stress, a study was conducted in the period from January 2020 to April 2021, at College of Medicine, Al-Nahrain University, Baghdad, Iraq. The Enzyme-linked immunosorbent assay (ELISA) technique was utilized for measurement the antioxidant enzymes including: Glutathione superoxide (GPX) and catalase (CAT) and the biomarker of lipid peroxidation Malondialdehyde (MDA). Also, the gene expression of Nrf2 and HO-1were determined by using RT-PCR technique. The results indicate lower level of both GPX and CAT (p ≤ 0.001) in smokers compared with non-smokers. While the result of MDA indicate higher level in smokers (p≤0.001) compared with nonsmokers. The Nrf2 and HO-1 gene exp

... Show More
Publication Date
Mon Apr 04 2022
Journal Name
Journal Of Educational And Psychological Researches
Fear of Intimacy and its Relationship with Post-Traumatic Stress Disorder among Yazidis Women
...Show More Authors

The current research aims to identify the fear of intimacy and post-traumatic stress disorder among Yazidi women and the correlation between them. To achieve the objectives of the research, the researcher adopted the Descutner, 1991 & (Thelen) scale, which consisted of (35) items. The researcher also adopted the post-traumatic stress disorder scale for (Davidson, 1995) translated by (Abdul Aziz Thabet), which consists of (17) items. These two scales were administered to a sample of (200) individuals. Then, the researcher analyzes the data using the Statistical Package for Social Sciences (SPSS). The results showed that the research sample of Yazidi women has a fear of intimacy. The research sample of Yazidi women is characterized by

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 06 2014
Journal Name
Journal Of Educational And Psychological Researches
The Intellectual Stress and Its Relationship with Personality' s Five Major Factors of Counselors
...Show More Authors

The current study aims at identifying:

1-The intellectual stress of counselors according to gender variable (male, female ).

2-The five major  factors of the  Counselor's  Personality.

3-  The relationship between intellectual stress and the five major factors of the councilors' personality and according to gender variable (male, female ).

4-The significant differences in the relationship between intellectual stress and the five major factors of the councilors' personality and according to gender variable  (male, female ).

The sample of the study includes (260) counselors (130 male

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 03 2005
Journal Name
Political Sciences Journal
ترجمة (عملية صناعة واتخاذ القرار في السياسة الخارجية للرئيس جورج والكر بوش)
...Show More Authors

عملية صناعة واتخاذ القرار في السياسة الخارجية للرئيس جورج والكر بوش

View Publication Preview PDF
Crossref
Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Study of opacity broadening in spectral lines for helium like ions in aluminum plasma which produced by laser
...Show More Authors

A theoretical analysis studied was performed to study the opacity broadening of spectral lines emitted from aluminum plasma produced by Nd-YLF laser. The plasma density was in the range 1028-1026 )) m-3 with length of plasma about ?300) m) , the opacity was studied as function of plasma density & principle quantum number. The results show that the opacity broadening increases as plasma density increases & decreases with the spacing between energy levels of emission spectral line.

View Publication Preview PDF
Crossref
Publication Date
Wed May 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Distribution of the Infection with Trichomonas vaginalis and Associated Microorganisms in Women Attending Two Hospitals in Al-Sader City, Baghdad
...Show More Authors

  A total  of 320  samples  of vaginal  swabs  was  obtained  from  women complaining of vaginal infection and attending two hospitals in Al-Sader city, Baghdad, namely Ibn AlBaladi Hospital for Pediatrics and Gynecology and Fatimat Al-Zahraa Hospital for Obstetrics in Al-Habibia district during the period from Desember 1997 till July 1998. Results of direct smear and culture showed  that Trichomonas vaginalis infection occurred in 19.1%, in addition to some microorganisms. The most common infection was by Candida spp. (24.7%), followed  by  Gardnerella  vaginalis (13.8%)  and  Staph. aureus  (10.9%). Infection with Escherichia coli, Klebsiella spp. and Prote

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 01 2021
Journal Name
Iraqi Journal Of Physics
Evaluate the Distribution of Heavy Elements that Dissolved in Ground Water Using IDW in AL-Wafa City, Al-Ramadi,Iraq
...Show More Authors

Groundwater can be assessed by studying water wells. This study was conducted in Al-Wafa District, Anbar Governorate, Iraq. The water samples were collected from 24 different wells in the study area, in January 2021. A laboratory examination of the samples was conducted. Geographical information systems technique was relied on to determine the values of polluting elements in the wells. The chemical elements that were measured were [cadmium, lead, cobalt and chromium]. The output of this research were planned to be spatial maps that show the distribution of the elements with respect to their concentrations. The results show a variation in the heavy elements concentrations at the studied area groundwater. The samples show different values

... Show More
View Publication Preview PDF
Crossref (8)
Crossref