Preferred Language
Articles
/
XBc2CpEBVTCNdQwCWZL7
Temperature and Stress Evaluation during Three Different Phases of Friction Stir Welding of AA 7075-T651 Alloy
...Show More Authors

The current study performs an explicit nonlinear finite element simulation to predict temperature distribution and consequent stresses during the friction stir welding (FSW) of AA 7075-T651 alloy. The ABAQUS® finite element software was used to model and analyze the process steps that involve plunging, dwelling, and traverse stages. Techniques such as Arbitrary Lagrangian–Eulerian (ALE) formulation, adaptive meshing, and computational feature of mass scaling were utilized to simulate sequence events during the friction stir welding process. The contact between the welding tool and workpiece was modelled through applying Coulomb’s friction model with a nonlinear friction coefficient value. Also, the model considered the effect of nonlinear material properties as well as heat transfer conditions such as heat losses due to convection and thermal contact conductance between the workpiece and the backing plate interface on the thermal history. To validate the computational model results, an experimental procedure was carried out to measure temperature history on both sides of the specimen as well as the plunging force throughout the whole process time. The results obtained showed that symmetrical temperature distribution throughout the workpiece width was distinguished, implying that the tool rotation has a minor effect on the final temperature distribution. In addition, asymptotic V shape with high gradient temperature value in the weld nugget region after the full plunging was distinguished. Mechanical stresses and related plastic deformations generated, while achieving the FSW samples were evaluated in addition to the tool reaction force and heat generated to protect against tool failure.

Scopus Clarivate Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
Math Word Problems in Mathematics Books for the First Three Grads of the Basic Stage in Palestine (An analytical and Evaluative Study)
...Show More Authors

This study aimed at revealing the degree of availability of standards of word problems in mathematics books for the first three grades of the basic stage in Palestine. For this purpose, the researcher prepared an analysis tool and a list of criteria consisting of two areas: linguistic formulation and mathematical content. Every area had seven items. The results of the study showed that the third-grade mathematics book has the highest degree of availability of the standards with 85.75%, and then came the second-grade mathematics book with 83.12%. Finally, the first-grade mathematics book came with 80.13%. In the light of the previous results, the researcher recommended to develop the language of word problems, to take into account their i

... Show More
View Publication Preview PDF
Publication Date
Thu Jan 15 2009
Journal Name
Journal Of Kerbala University
Viscosity and Volumetric studies of some amino acids in solutions at different temperatures
...Show More Authors

Densities ρ and viscosities η for several concentrations of amino acids (Serine, Cysteine and Threonine) at different temperatures (298.15, 303.15 and 308.15K) have been measured. On the basis of these data, the apparent molal volumes v , partial molal volumes at infinite dilution v , slope Sv , Gibbs free energy of activation for viscous flow of solution ∆G1,2 and Jones – Dole Bcoefficients were calculated the nature of solute-solvent and solute-solute interactions have been discussed in terms of the values of v , v , Sv and B-coefficents

Publication Date
Sat Jun 03 2023
Journal Name
Iraqi Journal Of Science
Effect of Different Environmental and Nutritional Factors on Biosurfactant Production from Candida guilliermondii
...Show More Authors

Yeast strain S9, which produced a high amount of biosurfactant, was isolated from pickledolive and identified as a strain of Candida guilliermondii using VITTEK 2 compact system, this strain was selected out of 13bioemulsifier producing strains. The effects of some environmental and nutritional factors on biosurfactant production were evaluated, the maximum value of E24% was observed at pH 4 which was 70% and the optimal temperature for biosurfactant production was 30 °C, E24% was 75%. Among different edible and heavy oils, the sesame oil and heavy oil 150 were the best carbon sources in production of biosurfactant, E24% was82% and 78% respectively and among different organic and inorganic nitrogen sources, the yeast extract was the bes

... Show More
View Publication Preview PDF
Publication Date
Fri Jul 28 2017
Journal Name
Iraqi Journal Of Science
Morphological and Optical Properties of CdS Quantum Dots Synthesized with different pH values
...Show More Authors

View Publication
Crossref
Publication Date
Sun Dec 05 2021
Journal Name
Iraqi Journal Of Science
Morphological and Optical Properties of CdS Quantum Dots Synthesized with different pH values
...Show More Authors

Quantum dots (QDs) of cadmium sulfide (CdS) was prepared by chemical
reaction method with different potential of hydrogen (pH) values. The
morphological and optical measurements of cadmium sulfide QDs were considered
by atomic force microscopy (AFM), ultraviolet-visible (UV-VIS.) and
photoluminescence (PL) spectrometer respectively. The energy gap (Eg) was
calculated from photoluminescence spectra were found to be about 2.7, 2.6 and 2.5
eV at pH values 8, 10 and 12 respectively for CdS QDs. The decreasing of energy
gaps is rises from the effect the pH solution increases, which in turn leads to the
shifted of the PL spectrum toward red shifted, which creates the energy bands at
surface states are shallow bands.

... Show More
View Publication Preview PDF
Publication Date
Thu Dec 28 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Grafting of Different Monomers onto Nano Aluminum Surface and Studying Their Biological Activities
...Show More Authors

The research includes the preparation of two nano polymer (   ,    ) through a grafted nano ceramic material (aluminum oxide      )(80 nm) by acrylic acid monomer. The latter was extended with two different ester monomers using free radical polymerization. The antibacterial activity of the prepared compounds) performed according to the agar diffusion method.  All compounds (1, 2, 3, 4, NP1, NP2) showed inhibition against bacterial

View Publication Preview PDF
Crossref
Publication Date
Sun Apr 16 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Theoretical Design of Electrostatic Lens Accelerating and Decelerating Operated Under Different Magnification Conditions
...Show More Authors

  In this paper,  design computationl investigation in the field of charged-particle optics with the aid of numerical analysis methods  under the absence of space charge effects. The work has been concentrated on the design of three-electrode  einzel electrostatic  lens accelerating and decelerating operated under different magnification conditions.     The potential field distribution of  lens has been represented by exponential function.  The paraxial-ray equation has been solved for the proposed field to determine the trajectory of charged-particles traversing in the lens.  From The axial  potential distribution and its first and second derivatives, the optical propertie

... Show More
View Publication Preview PDF
Publication Date
Sun Feb 27 2011
Journal Name
University Of Baghdad
Determination of Cimetidine and Erythromycin ethylsuccinate Drugs Using Different Spectrophotometric Methods (Ph.D. Thesis)
...Show More Authors

In this study, four different spectrophotometric methods were applied for determination of cimetidine and erythromycin ethylsuccinate drugs in pure form and in their pharmaceutical preparations. The suggested methods are simple, sensitive, accurate, not time consuming and inexpensive. The results showed the following: The first method: Based on the formation of ion pair complex of each drug with bromothymol blue (BTB) as a chromogenic reagent. The formed complexes were extracted with chloroform and their absorbance values were measured at 427.5 nm for cimetidine and 416.5nm for erythromycin ethylsuccinate; against their reagents blanks. Two different methods, univariate method and multivariate method, were used to obtain the optimum condit

... Show More
Preview PDF
Publication Date
Wed Oct 08 2008
Journal Name
Journal Of Kerbala University
Viscosity and Volumetric studies of some amino acids in solutions at different temperatures.
...Show More Authors

Publication Date
Thu Nov 21 2019
Journal Name
Al-kindy College Medical Journal
Investigate The Different Effect Of Nicotine On H460 And H441 Lung Cells Viability
...Show More Authors

Background: Nicotine is the foremost chemical constituent responsible for addiction in tobacco products, in the non-ionized condition can be easily absorbed via epithelial tissue of the lung, the mouth, the nose  and across the skin

Objective:The study examines the harmful effect of   the nicotine which is an important component of cigarette in vitro.

Type of the study: Cross-sectional study.

Methods: Examines the harmful effect of   the nicotine which is an important component of cigarette in vitro by using two types of lung cancer cell lines (H460 TP53+/+, H441 TP53-/-).

... Show More
View Publication Preview PDF
Crossref