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.
This study includes isolation , purification and identification of algae from different
aquatic environments in Baghdad.
Two different plant species belonging to different families were selected which were
Citrilluscolocynthus and Cordiamyxa for their fruits and fruits samples respectively.
Crude extracts were extracted from each plant and their antialgal activity were
evaluated.Different concentrations (5,15,25) mg/ml of these extracts were prepared
and their antagonistic activity was studied, and the resulted inhibition effects in ( %)
of concentration of chlorophyll(a) after 12 days was evaluated.
Results showed that Chloroccumhumicola was the most sensitive to these extracts.
However, Anabaena circinalis wa
Artificial roughness applied to a Solar Air Heater (SAH) absorber plate is a popular technique for increasing its total thermal efficiency (ηt−th). In this paper, the influence of geometrical parameters of V-down ribs attached below the corrugated absorbing plate of a SAH on the ηt−th was examined. The impacts of key roughness parameters, including relative pitch p/e (6–12), relative height e/D (0.019–0.043), angles of attack α (30–75°), and Re (1000–20,000), were examined under real weather conditions. The SAH ηt−th roughened by V-down ribs was predicted using an in-house developed conjugate heat-transfer numerical model. The maximum SAH ηt−th was shown to be 78.8% as predicted under the steady-state condition
... Show MoreColorectal cancer (CRC) Patients showed different expression patterns of miRNAs which are involved in carcinogenesis in comparison to healthy controls individuals, miRNAs are involved in tumor progression and development of metastases. We investigate the expression profile of microRNA 320 and to quantify the expression level abundance among colorectal cancer patients in comparison to the healthy control group. The A total number of 60 plasma samples was collected from CRC patients along with 40 plasma samples from healthy controls and subjected to relative quantification using qPCR assay with a specified set of primers designed using s
... Show MoreForty-four bottles of drinking water were collected from the local markets of Basra City and stored in the laboratory refrigerator at 4ºC until the physical, chemical and biological measurements were carried out. The results showed a discrepancy in the compatibility of the specifications written on the drinking water bottle label with the sample measurements as well as the variation in the results with the Iraqi standards for bottled water. The percentage of bottled water that is not safe for drinking was 88.5% of the total samples of the study. This value is high and an indication of lack of control over marketing from the imported or produced in the local labs, s
... Show MoreObjective: To evaluate the nurse's practices and it's relationship between with thier demographic characteristic.
Methodology: A descriptive study was carried out , from January 15th 2002 to April 15th 2002 , to evaluate the
nurse’s practices toward patients who undergo cardiac catheterization . A purposive sample of ( 65 ) nurse , was
selected out of three teaching hospitals in Baghdad city . These nurses were worked at the catheterization units
and catheterization labs .A questionnaire was constructed for the purpose of the study , which comprised of three
major parts in which there were ( 45 ) items . Reliability and validity of the questionnaire were determined
through the conduct of a pilot study .
Data were c
The local study were selected 70 Iraqi Arab Patients (39 females and 31 males), who referred to HLA laboratory in teaching laboratories in Baghdad medical city from April 2009 – May 2010 were diagnosed with Behcete's disease, C-reactive protein concentration(CRP) was evaluated by ELISA technique, anti-nuclear antibody (ANA) and anti-neutrophil cytoplasmic antibody (ANCA) were evaluated by Indirect immunofluorescence technology. The result showed significant differences (P<0.05) of CRP concentration in patients group compared with control, negative antinuclear nuclear antibody in all cases while ANCA was positive in 8.5% of patients with type P (PANCA). These results lead to suggest that ANCA auto-antibody may have a role in triggeri
... Show MoreObjectives: Evaluation of school health surveillance system with Indicate the level of usefulness of this system,
in addition to Describe the system.
Methodology: A probability multistage sample of (54) subjects which is selected the school health units from
the health institutions. Questionnaire has been divided into three main parts consist, form(A) especially for
health directorate, form (B) for health sectors, and form (C) for primary health care centers; each form contains
the basic components, structure, process, outcome, total items of questionnaire was ( 74) items.
Results: The study results indicate that the system is average adequacy, simple, moderately flexible, highly
acceptance, representative, low utili
Abstract
The economic and financial crises in the world economy series led to increased awareness of the importance of the internal control system, because it is one of the main pillars of any economic unit, as it works to verify the application of policies, regulations and laws and verification of asset protection from theft and embezzlement procedures, it is also working on trust accounting information imparted through the validation of accounting information, analyze and detect the misleading.
The existence the internal control system a factor in many of the accounting practices that limit the ability of the administration to produce misleading financial reporting
The
... Show MoreThe aim of this study was to investigate the disturbances of some liver enzymes like GPT and GOT level in different groups of women infected with toxoplasmosis. This study was performed on 600 apparently healthy women (pregnant, miscarriage and single) collected from different hospitals in Baghdad, AL-Yarmouk Teaching Hospital and Fatima AL-Zahra Hospital for Obstetric and children and Hay Hiteen clinic during November 2013 till April 2014. The detection of toxoplasmosis was done by a preliminary screening test LAT and the positive percentage was (29.55%), (30.36%) and (40.08%) for pregnant, miscarriage and single women respectively. While, the confirmation of positive results of LAT was done by ELISA-IgG and the results were (40%), (41.
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