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.
raqi species of (Euphorbia lathyris F. Euphorbiaceae) have been used in the present study to evaluate genotoxicity of petroleum ether fraction in two doses (100mg/kg and 200mg/kg) on bone marrow cells in mice for seven successive days, comparing their effects with a positive control (methotrexate at a dose 20 mg/kg). Both doses of petroleum ether fraction of Euphorbia Lathyris significantly decrease mitotic index (P<0.05) compared to dimethylsulfoxide (negative control) group. For total chromosomal aberration, the petroleum ether fraction of Euphorbia lathyris (in both doses) produced significant increase (P<0.05) compared to dimethyl sulfoxide (negative control) group .at the same time, 20mg/kg methotrexate significantly increases (P<0.05)
... Show MoreThis research aims to analyze the intellectual and civilizational regression that afflicted Iraqi and Arab society due to political and religious tyranny and internal conflicts, which was reflected in the deterioration of human rights values and the absence of equality and justice in dealing with the other religiously, which affected the reluctance of members of religious groups to interact with their national societies and then migrate to Outside, which contributed to a double loss, in terms of the loss of these societies by productive and effective national competencies, and in terms of distorting the image of Islam. The research stressed that the first treatments of this phenomenon are the consolidation of the values of citize
... Show MoreFor aspirin estimated, a molecularly imprinted polymer MIP-ASP electrodes were generated by electro-polymerization process, the electrodes were prepared by combining the template (aspirin) with (vinyl acetate (VA), 1-vinylimidizole (VIZ) as a functional monomer and N, N-methylene bisacrylamide (MBAA) as crosslinkers using benzoyl peroxide (BPO) as an initiator. The efficiency of the membrane electrodes was analyzed by differential pulse voltammetry (DPV). Four electrodes were synthesized using two different plasticizers, di-butyl sebacate (DBS), di-octyl phthalate (DOP) in PVC matrix. Scanning electron microscopy (SEM) was used to describe the generated MIP, studying the electrodes properties, the slope, detection limit, and life
... Show MoreThe study was conducted to show the effect of using dried rumen powder as a source of animal protein in the diets of common carp (Cyprinus carpio L.) on its performance, in the fish laboratory/College of Agricultural Engineering Sciences/University of Baghdad/ for a period of 70 d, 70 fingerlings were used with an average starting weight of 30±3 g, with a live mass rate of 202±2 g, randomly distributed among five treatments, two replicates for each treatment and seven fish for each replicate. Five diets of almost identical protein content and different percentages of addition of dried rumen powder were added. 25% was added to treatment T2 and 50% to treatment T3 and 75% of the treatment T4 and 100% of the treatment T5
... Show MoreAphelenchus avenae was isolated from the wheat crown in Summel distract- Duhok, Kurdistan region-Iraq infected by a crown rot disease which is caused by Fusarium spp; wheat's crown culturing on Potato Dextrose Agar (PDA) and incubating at 25°C A. avenae was found associated with fungal culture which meant that fungal nematode was parasitic on crown rot fungi on wheat crown, this species was described for the first time in Iraq.
Fungal Nematode incubated with Fusarium graminearum, F. oxysporum and Verticillium dahliae reproduce in both solid and liquid media, best results of nematode reproduction were recorded on F. graminearum followed by F. oxy
... Show MoreIn this study, Al2O3 thin films were prepared by dc reactive sputtering technique using different gas mixtures of argon and oxygen gases (90:10, 70:30, 50:50, 30:70, and 10:90). These films were characterized to introduce their surface morphology and elemental composition as functions of the oxygen content in the gas mixture. The gas mixing ratio plays a crucial role in controlling the nanoscale morphology of the prepared thin films. The [Al]/[O] ratio varies non-linearly with the Ar:O2 mixing ratio. Increasing the oxygen content leads to a progressive decrease in surface roughness, resulting in smoother and more uniform films with finer granular features. These results presented herein are useful to optimize the sputtering process to ac
... Show MoreThe present study was undertaken to use individual terrestrial crustacean from Isopoda such as the species Porcellionides pruinosus (Brandt 1833) as environmental cleaner and that through the test of their abilities in decomposition of residues of some cellulosean wastes such as wood pieces which contain high ratio of urban wastes, and residue of Zea mays and particularly leaves as plant waste in agricultural fields and residue of Cynodon dactylon plants which compose the main wastes in most of gardens and parks. Experiments were conducted relatively in stable laboratory conditions to ensure environmental conditions similar to crustaceans' life. The results showed presence of good efficiency of these individuals in treating such wastes as
... Show MoreIntroduction: Nitrofurantoin (NFT) is abroad spectrum bactericidal antibiotic. The bioavailability of NFT is affected by many factors. Samafurantin® tablets containing 50 mg NFT were manufactured by Samarra drug industry. Urinary excretion studies were employed since; the urinary tract is the main site of NFT action and excretion. Objective: The objective of the study was to investigate the effect of Uricol® and food on secondary pharmacokinetic parameters of Samafurantin® tablets with different doses by applying urinary data. Methods: Twelve healthy male volunteers participated in this study. Urine samples were collected from each volunteer after overnight fasting at a specified time intervals which considered as a blank sample for meas
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