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The effect of silanized alumina nano -fillers addition on some physical and mechanical properties of heat cured polymethyl methacrylate denture base material
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Background: Polymethyl methacrylate (PMMA) is the most commonly used material in denture fabrication. The material is far from ideal in fulfilling the mechanical requirements. Midline fracture; poor thermal conductivity and water sorption, are common problem in this material. The purpose of this study was to evaluate the effect of addition of surface treated Aluminum oxide nano fillers on some properties of heat cured (PMMA). Materials and methods: In addition to controlled group of heat cured PMMA the silanized (Al2O3) nanoparticles was added to PMMA powder by weight in three different percentages 1wt%, 2wt% and 3wt%, mixed by probe ultra-sonication machine. 200 specimens were constructed and divided into 5 groups according to the test (each group consist of 40 specimens) and each group was subdivided into 4 sub-groups. The tests conducted were thermal conductivity, thermal diffusivity, transverse strength, indentation hardness (shore D), surface roughness, water sorption and solubility. The results were statistically analyzed using ANOVA and Dunntt t-test. Results: A highly significant increase in transverse strength was observed with the addition of (Al2O3) nanoparticles to (PMMA) at the percentage of 1wt%, the value was 117.72 Mpa and significant increase at 2wt%; while a significant reduction occurred in transverse strength at the percentage of 3% the value was 90.110 Mpa. A significant increase in surface hardness and non significant differences in surface roughness were observed for all percentages. Conclusion: The addition of Al2O3 nanoparticles to acrylic resin improves the thermal properties and transverse strength of acrylic resin at the same time this addition decreases water sorption and solubility.

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Publication Date
Thu May 04 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of GA3, Thiamine in Some Yield Component and Active Substance on Cumin (Cuminum cyminum L.)
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The experiment was conducted at field of garden of Department of Biology, Collage
of Education (Ibn-Al-Haitham) University of Baghdad during winter season of 2009-2010.
The aim of present study is the effect of growth regulator Gibberellins by using two
concentrations (100, 200) ppm and also Thiamine in two concentrations (10, 50) ppm, on the
some yield component characters and active component of volatile oil Cumin (Cuminum
cyminum L.).
The results showed that GA3 in (100) ppm increased the yield component, protein
concentration and increased in Cuminaldehyde, Perillaldehyde and Thyoml concentration.
The results showed that the best concentration was (50) ppm of Thiamine showed an
increasing concentratio

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Publication Date
Wed Aug 09 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Ascorbic Acid on Pathogenic Staphylococcus aureus Growth singly and in Combination with Some Antibiotics
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 One hundred and fifteen isolates of Staphylococcus aureus were isolated from human infected wound and burn. The resistance of this organism for eight commonly used antibiotics was determined by disc diffusion methods.          The minimum inhibitory concentration MIC was determined for each drug by tube dilution method. Results showed significant variations in the MIC values. It was found that two isolates had high resistance for the eight antibiotics used. Effect of ascorbic acid on bacterial growth was studied singly and in combination with antibiotics. Reductions in MIC value were reported for different antibiotics when tested by growth curve method too. 

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Publication Date
Wed Dec 01 2021
Journal Name
Iraqi Journal Of Physics
Effect of Zinc (Zn) -Doped on the Structural, Optical and Electrical Properties of (Cdo)1-Xznx Films Prepared by Pulsed Laser Deposition Technique
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Pure cadmium oxide films (CdO) and doped with zinc were prepared at different atomic ratios using a pulsed laser deposition technique using an ND-YAG laser from the targets of the pressed powder capsules. X-ray diffraction measurements showed a cubic-shaped of CdO structure. Another phase appeared, especially in high percentages of zinc, corresponding to the hexagonal structure of zinc. The degree of crystallinity, as well as the crystal size, increased with the increase of the zinc ratio for the used targets. The atomic force microscopy measurements showed that increasing the dopant percentage leads to an increase in the size of the nanoparticles, the particle size distribution was irregular and wide, in addition, to increase the surfac

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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Educational And Psychological Researches
The effect of using active learning model in the achievement of fourth -grade material in the de partment of physics teaching aids students and the development then critical thinking
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Goal  of  research  is  to  investigate  the  impact  of the  use  of  effective  learning  model in the  collection  of  the  fourth  grade  students/Department of  physics in the material  educational methods  and the  development  of  critical thinking  .to teach  this goal  has  been  formulated  hypothesis cefereeten zero  subsidiary  of the second hypothesis  .To  investigate  the  research  hypothesis  were  selected  sample  of  fourth-grade  students of the  department  of physics at the univers

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Publication Date
Fri Nov 26 2021
Journal Name
Nanomaterials
Solidification Enhancement in a Multi-Tube Latent Heat Storage System for Efficient and Economical Production: Effect of Number, Position and Temperature of the Tubes
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Thermal energy storage is an important component in energy units to decrease the gap between energy supply and demand. Free convection and the locations of the tubes carrying the heat-transfer fluid (HTF) have a significant influence on both the energy discharging potential and the buoyancy effect during the solidification mode. In the present study, the impact of the tube position was examined during the discharging process. Liquid-fraction evolution and energy removal rate with thermo-fluid contour profiles were used to examine the performance of the unit. Heat exchanger tubes are proposed with different numbers and positions in the unit for various cases including uniform and non-uniform tubes distribution. The results show that

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Publication Date
Thu Jan 11 2018
Journal Name
Al-khwarizmi Engineering Journal
The Linear and Nonlinear Electro-Mechanical Fin Actuator
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Electromechanical actuators are used in a wide variety of aerospace applications such as missiles, aircrafts and spy-fly etc. In this work a linear and nonlinear fin actuator mathematical model has been developed and its response is investigated by developing an algorithm for the system using MATLAB. The algorithm used to the linear model is the state space algorithm while the algorithm used to the nonlinear model is the discrete algorithm. The huge moment constant is varied from (-3000 to 3000) and the damping ratio is varied from (0.4 to 0.8).        

 The comparison between linear and nonlinear fin actuator response results shows that for linear model, the maximum overshoot is about 10%,

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Publication Date
Mon Dec 25 2000
Journal Name
Journal Of Advanced Research In Fluid Mechanics And Thermal Sciences
Enhancement of nanofluid heat transfer in elliptical pipe and helical micro tube heat exchanger
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Publication Date
Thu Oct 01 2020
Journal Name
Journal Of Energy Storage
Improved melting of latent heat storage via porous medium and uniform Joule heat generation
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Publication Date
Thu Dec 01 2022
Journal Name
Environmental Nanotechnology, Monitoring & Management
Synthesis of nano-magnetite and magnetite/synthetic geopolymer nano-porous composite for application as a novel adsorbent
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In this work magnetite/geopolymer composite (MGP) were synthesized using a chemical co-precipitation technique. The synthesized materials were characterized using several techniques such as: “X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), vibrating sample-magnetometer (VSM), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), Brunauer–Emmett–Teller (BET) and Barrentt-Joyner-Halenda (BJH)” to determine the structure and morphology of the obtained material. The analysis indicated that metal oxide predominantly appeared at the shape of the spinel structure of magnetite, and that the presence of nano-magnetite had a substantial impact on the surface area and pore st

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Publication Date
Tue Jun 01 2021
Journal Name
Iraqi Journal Of Physics
Study of the Static and Dynamic Nuclear Properties and Form Factors for Some Magnesium Isotopes 29-34 Mg
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Nuclear structure of 29-34Mg isotopes toward neutron dripline have been investigated using shell model with Skyrme-Hartree–Fock calculations. In particular nuclear densities for proton, neutron, mass and charge densities with their corresponding rms radii, neutron skin thicknesses and inelastic electron scattering form factors are calculated for positive low-lying states. The deduced results are discussed for the transverse form factor and compared with the available experimental data. It has been confirmed that the combining shell model with Hartree-Fock mean field method with Skyrme interaction can accommodate very well the nuclear excitation properties and can reach a highly descriptive and predictive power when investiga

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