Nanoferrite materials have been synthesized by sol-gel auto combustion method. The effect of doping different percentages of Y2O3 (0.34 µm) on the physical and mechanical properties of selected mixed ferrite [(Li2.5Fe0.5) 0.9(Co4Fe2O4) 0.1] by adding 10% Cobalt ferrite was studied. Physical properties (i.e. .density, porosity and water absorption) were affected by the doping, where the density increased about 32% at 6 wt% Y2O3, while porosity has a drastically decreased about 80% at 6% Y2O3 and has a correlation effect on the mechanical properties(Splitting tensile strength and Vickers microhardnss). The fracture strength at 1 % wt. of Y2O3 has doubled value of the undoped sample and then decreased. The same behavior shows with the testing of Vickers micro hardness.SEM ( Scanning electron microscopy ) micrographs revealed that the microstructure of the fracture surface of the samples consist of detached approximately closely packed particles and also showed the formation of micro agglomerated particles with some voids . By doping with Y2O3 the pores decreased and a dense material obtained
Antibiotics resistant bacteria have become a global problem as a result of the unprogrammed use of antibiotics, resulting in bacterial strains resistant to many antibiotics, or to all available antibiotics. Plants are a good source of primary and secondary metabolites that have a major role in reducing silver nitrate to silver nanoparticles (AgNPs). The production of these nanoparticles were carried out by using aqueous extract of Carthamus oxycantha M.Bieb. This can be verified by color change of the reaction solution from yellow to dark brown because of the excitation of the surface plasmon resonance. AgNPs were characterized by UV-Vis spectroscopy, where they recorded the peak at 420 nm. Fourier Transformation-infrared (FTIR)
... Show MoreOne technique used to prepare nanoparticles material is Pulsed Laser Ablation in Liquid (PLAL), Silver Oxide nanoparticles (AgO) were prepared by using this technique, where silver target was submerged in ultra-pure water (UPW) at room temperature after that Nd:Yag laser which characteristics by 1064 nm wavelength, Q-switched, and 6ns pulse duration was used to irradiated silver target. This preparation method was used to study the effects of laser irradiation on Nanoparticles synthesized by used varying laser pulse energy 1000 mJ, 500 mJ, and 100 mJ, with 500 pulses each time on the particle size. Nanoparticles are characterized using XRD, SEM, AFM, and UV-Visible spectroscopy. All the structural peaks determined by the XRD
... Show MoreSpin coating technique has been applied in this work to prepared Xerogel films doped with Rhodamine 6G laser dyes. The solid host of laser dye modifies its spectroscopic properties with respect to liquid host. During the spin coating process the dye molecules suffer from changing their environment. The effects of three parameters were studied here: the spinning speed, multilayer coating and formaldehyde addition
In this study, gold nanoparticle samples were prepared by the chemical reduction method (seed-growth) with 4 ratios (10, 12, 15 and 18) ml of seed, and the growth was stationary at 40 ml. The optical and structural properties of these samples were studied. The 18 ml seed sample showed the highest absorbance. The X- ray diffraction (XRD) patterns of these samples showed clear peaks at (38.25o, 44.5o, 64.4o, and 77.95o). The UV-visible showed that the absorbance of all the samples was in the same range as the standard AuNPs. The field emission-scanning electron microscope (FE-SEM) showed the shape of AuNPs as nanorods and the particle size between 30-50 nm. Rhodamine-610 (RhB) was prepared at 10<
... Show MorePure and doped TiO 2 with Bi films are obtained by pulse laser deposition technique at RT under vacume 10-3 mbar, and the influence of Bi content on the photocvoltaic properties of TiO 2 hetrojunctions is studied. All the films display photovoltaic in the near visible region. A broad double peaks are observed around λ= 300nm for pure TiO 2 at RT in the spectral response of the photocurrent, which corresponds approximately to the absorption edge and this peak shift to higher wavelength (600 nm) when Bi content increase by 7% then decrease by 9%. The result is confirmed with the decreasing of the energy gap in optical properties. Also, the increasing is due to an increase in the amount of Bi content, and shifted to 400nm when annealed at 523
... Show MoreBasketball is a popular game in many parts of the world and many developed countries are making continuous efforts to prepare and develop their emerging players on scientific and clear bases as the basis for reaching high levels The researchers used the descriptive approach in the method of correlative studies to suit the nature of the study The readymade software (IBM SPSS Statistics Version24) was used to perform statistical treatments The researchers concluded that there was a significant relationship between body size indicators (height and weight) with the fitness elements of the emerging basketball players The researchers recommended conducting a similar study to determine the type of relationship to the indicators of the physical str
... Show Moreيعد القلق من الكتابة مؤشرا هاما قد يعيق القدرات الكتابية ويؤدي إلى عدم كفاءة الأداء. تهدف هذه الدراسة إلى تقييم القلق الكتابي لدى طلاب السنة الرابعة في كلية التربية البدنية وعلوم الرياضة العراقيين دارسي اللغة الإنجليزية كلغة ثانية (ESL) , حيث واجهوا صعوبات وعقبات في هذا المجال. ان تصميم الدراسة الحالية هو تصميم وصفي واداة القياس لهذه الدراسة تتالف من مقياس مكون من (20) فقرة. ان عينة الدراسة الحالية مختارة
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