Zinc Oxide nanoparticles were prepared using pulsed laser ablation process from a pure zinc metal placed inside a liquid environment. The latter is composed of acetyltrimethylammonium bromide (CTAB) of 10−3 molarity and distilled water. A Ti:Sapphire laser of 800 nm wavelength, 1 kHz pulse repetition rate, 130 fs pulse duration is used at three values of pulse energies of 0.05 mJ, 1.11 mJ and 1.15 mJ. The evaluation of the optical properties for the obtained suspension was applied through ultraviolet–visible absorption spectroscopy test (UV/VIS). The result showed peak wavelengths at 210 nm, 211 nm and 213 nm for the three used pulse energies 0.05 mJ, 1.11 mJ and 1.15 mJ respectively. This indicates a blue shift, which means smaller sizes of prepared nanoparticles, correlated with the decrease in laser energy. The blue shift in the absorption edge refers to the quantum confinement property for the produced nanoparticles. In addition, Fourier Transform Infrared Spectroscopy (FTIR) analysis was utilized to confirm zinc oxide nanoparticles formation represented by the absorption values at 435–445 cm−1. The shape and morphology of ZnO nanoparticles were characterized with scanning electron microscope (SEM).
Abstract: Despite the distinct features of the continuous wave (CW) Terahertz (THz) emitter using photomixing technique, it suffers from the relatively low radiation output power. Therefore, one of effective ways to improve the photomixer emitter performance was using nanodimensions electrodes inside the optical active region of the device. Due to the nanodimension sizes and good electrical conductivity of silver nanowires (Ag-NWs), they have been exploited as THz emitter electrodes. The excited surface plasmon polariton waves (SPPs) on the surface of nanowire enhances the incident excitation signal. Therefore, the photomixer based Ag-NW compared to conventional one significantly exhibits higher THz output signal. In thi
... Show MoreThe present study aims at finding out the (effect of the Caroll’s pattern on the second intermediate class pupils' achievement in geography)
The partial experimental design of two groups, experimental and control, with pre-post tests is used. The sample is represented in (74) female pupils. The sample is divided into two groups (38) experimental group and (36) control one. The sample is selected from first intermediate class pupils ( Am Salama Secondary School for girls) \ Baghdad\ Al-karkh-1, for academic year 2015-2016.
The researcher has equalized the two groups in several variables: the previous achievement tests, intelligence, age in months, the scor
... Show MoreThe new compounds of pyrazolines were synthesized from the reaction of different acid hydrazide with ethylacetoacetate and ethanol under reflux. These compounds were obtained from many sequence reactions. The 4-acetyl-5-methyl-2,4-dihydro-3H-pyrazol-3-one compounds synthesized from the reaction of 5-methyl-2,4-dihydro-3H-pyrazol-3-one with acetyl chloride in calcium hydroxide and 1,4-dioxane. Finaly, Schiff bases were prepared via condensation reaction of products of mono- and tri ketone derivatives[IV]a, b with phenyl hydrazines as presented in (Scheme 1, 2). The synthesized compounds were identification by using FTIR, NMR and Mass spectroscopy (of some of them).
The problem of research is that there are differences between learners in processing in formation in general and there is variation at the learners level perform scrolling skill of the passes up and down by the volley ball .Therefore the researchers decided to conduct astudy through which identify the relationship between information processing and the skill of scrolling from the top and bottom by the volleyball. The researchers used the descriptive approach by themethod of interconnectivity .Asampleconsist of21 students from first staye in collage of physical education and sports science for Girls(university of Baghdad) and attest has been applied(process information and scroll up and down) on the research sample after the required
... Show MoreThe study aimed to determine the effect of the flipped learning model in improving the acquisition of the overhand serve skill in volleyball among second-year students at the College of Physical Education and Sport Sciences, University of Baghdad, for the academic year 2024/2025. The study used an experimental design with a control group and pre-post testing, on a purposive sample consisting of 12 students. The model relied on watching short videos before class via the SGS application, and practical application in class at a rate of three sessions per week. The results showed a significant improvement in performance, as the calculated value (t = 5.356) exceeded the tabulated value (2.042) at a significance level of 0.05. The percentage of s
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