Resistance spot welding (RSW) aluminum alloys has a major problem of inconsistent quality from weld to weld, because of the problems of the non-uniform oxide layer. The high resistivity of the oxide causes strong heat released which influence significantly on the electrode lifetime and the weld quality. Much effort has been devoted experimentally to the study of the sheet surface characteristics for as-received sheet and surface pretreatment sheet by pickling in NaOH and glassblasted with three thicknesses (0.6, 1.0, and 1.5 mm) of AA1050. Three different welding process parameters energy setup as a low, medium, and high were carried. Tensile-shear strength tests were performed to indicate the weld quality. Moreover, microhardness tests, macro/micrographs, and
SEM/EDS examinations were carried out to analyze, compare, and evaluate the effect of surface conditions on the weldability. The as received sheet showed a higher electrical contact resistance because of its thicker and non-uniform oxide layer. In contrast, the glass-blasted sheet showed lower value, since it has a roughest surface, which leads to easy breakdown the oxide layer. The highest average values and least scattering of the maximum load fracture are with treated sheet by
pickling in NaOH, these values are 760, 1193, and 2283 N for 0.6, 1.0, and 1.5 mm sheet thickness respectively for medium input energy. In contrast, the minimum values with glass-blasted sheet are 616, 1008, and 2020 N for 0.6, 1.0, and 1.5 mm sheet. The microhardness profiles of the fusion zone and HAZ is the lower than the base metal for all cases. Numerical simulation with SORPAS® was used to simulate and optimize the process parameters, and it has given good results in prediction when they compared with experiments.
Microalgae culture is an interesting step in wastewater treatment since it provides a tertiary biotreatment while also producing potentially valuable biomass that may be used for a variety of applications. Microalgae cultures, with their ability to utilize inorganic nitrogen and phosphate for growth, provide an elegant solution to tertiary and quaternary treatments. Scenedesmus quadricauda culture was employed with three different doses, 2g/l, 1g/l, and 0.2g/l, to investigate the impacts of microalgae in wastewater. Standard procedures were used to measure samples for physicochemical parameters such as pH, EC, PO4, NO3, NO2, NH4 and BOD5 every third day for
... Show MoreObjectives: The study objectives are to determine the impact of education program upon the academic nurses'
practice concerning documentation of nursing sheets, and to find out the relationship between nurses knowledge
and their demographic characteristics, which include age, sex, and years of experience in medical and surgical
wards.
Methodology: A quasi- experimental study was carried out at the medical and surgical wards in teaching
hospitals in Sulaimani governorate from the beginning of March up to June 2007٠
To reach the objectives of the study anon-probability (purposive) sample of (25) academic nurses who work in
the medical and surgical wards in teaching hospitals.
The data were collected through the use
Resistance to aminoglycosids is a great problem to therapeutics. Aminoglycoside acetyltransferase producing Pseudomonas aeruginosa have been reported to be important cause of nosocomial infections. The purpose of this study was to determine the occurrence of aminoglycoside acetyltransferase. A total of 200 clinical and environmental samples were collected over period of five months. The P. aeruginosa isolates were confirm their identification, antibiotic susceptibility profile according to vitek2 compact system. The isolates were subjected to polymerase chain reaction (PCR) assays with specific primers for aac (6')-I, aac (6')-Ib, aac (3')-I . Only 32 (16.%) P. aeruginosa isolates were recovered from the samples. in present investigation
... Show MoreThis study investigated the prevalence of quinolones resistance proteins encoding genes (qnr genes) and co-resistance for fluoroquinolones and β-lactams among clinical isolates of Klebsiella pneumoniae. Out of 150 clinical samples, 50 isolates of K. pneumoniae were identified according to morphological and biochemical properties. These isolates were collected from different clinical samples, including 15 (30%) urine, 12 (24%) blood, 9 (18%) sputum, 9 (18%) wound, and 5 (10%) burn. The minimum inhibitory concentrations (MICs) assay revealed that 15 (30%) of isolates were resistant to ciprofloxacin (≥4µg/ml), 11 (22%) of isolates were resistant to levofloxacin (≥8 µg/ml), 21 (42%) of isolates were re
... Show Moreان تصنيع رمال مطلية بأوكسيد الحديد من خلال ترسيب الجزيئات النانوية لذلك الاوكسيد على سطوح الرمال واستخدامها في الحاجز التفاعلي النفاذ لإزالة ايونات الكادميوم والنحاس من المياه الجوفية الملوثة الهدف الرئيسي للدراسة الحالية. تم توصيف بيانات الامتزاز نتيجة تفاعل المادة المازة مع المادة الممتزة قيد الدراسة بشكل جيد من خلال نموذج لانكمير والذي كان أفضل من نموذج فراندلش. لقد وجد ان اعلى قيم لقابلية الامتزاز با
... Show MoreStudies were conducted to evaluate the biological effects of the non-steroidal ecdysone agonist (Methoxyfenozide), on different developmental larval stages of cotton leafworm Spodoptera littoralis (Boisd.) in the laboratory. The results showed that the early larval stages were the most susceptible to Methoxyfenozide which caused 100% mortality within 4-6 days after treatment at all used concentrations, while such percentage of mortality was achieved within 6 days after treatment for late larval stages when the highest concentration was used (0.2)g (ai) /L. Several morphological deformations were noticed on pupal stage, the results showed that the highest percentage of deformations was 1
... Show MoreTitanium alloy (Ti-6Al-4V or Gr.23) was widely used as a dental alloy. In the current study, polymerization of eugenol (PE) on Gr.23 titanium alloys was conducted by an electrochemical process before and after being treated by Micro Arc Oxidation (MAO). The formed films were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The corrosion behavior of Gr.23 alloy in an artificial saliva environment at a temperature range of 293–323 K has been studied and assessed by means of electrochemical polarization and impedance spectroscopy techniques. Three cases are taken into consideration; bare Gr.23, Gr.23 coated by PE, and Gr.23 coated by PE after MAO treatment. The maxi
... Show MoreThe study aims to biosynthesized of sliver nanoparticle from aqueous extract of olive leave and evaluate the effectiveness of the synthesis AgNPs against isolated fungi. The study mediating fifty samples were taken from various tools in laboratory from five hospitals in Baghdad. Four species of fungi were identified depending on the morphological and microscopic characteristics. The most common isolated fungi based on their frequency ratio were as follows Aspergillus niger 87.5%, Aspergillus flavus 62.5%, Aspergillus fumigatus 53.5% and Aspergillus nidulans 37.7%.The Biosynthesis of silver nanoparticle developed a rapid, eco-friendly and convenient green method for the stable silver nanoparticles (AgNP
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