Pumpkin waste powder was used as a coloring and strengthening filler in epoxy to prepare a natural gelcoat . The Pumpkin powder was mixed with different weight ratios (1, 2, 3, 4, 5, 6, 7, and 8%) to the epoxy matrix to select the best value of powder addition. The effect of the pumpkin particle size on the mechanical properties (impact, flexural, hardness, and wear loss) using two different sizes (2.5 and 1.25 microns) was studied. The impact strength increased from (10.09 KJ/ m2) for neat epoxy to (14.79 KJ/ m2) for epoxy with 1% of micron pumpkin fibers ( MPF) with particle size 2.5 micrometer and (14.21 KJ/ m2) for epoxy with 4% (1.25 MPF), flexural strength increased from (41.94 MPa) for neat epoxy to (~ 46 MPa) for epoxy with 1% of 2.5 MPF and to (50.17 MPa) for epoxy with 4% of 1.25 MPF, hardness of neat epoxy was (~ 77) and almost maintained its value for epoxy with 1% of 2.5 MPF and for epoxy with 4% of 1.25 MPF. At almost the weight fractions addition of pumpkin fibers to epoxy, the (EP/1.25MPF) composite shows a higher wear resistance than the (EP/2.5MPF) composite. The density, thermal conductivity, and water diffusion (for 1-4 weeks' immersion) of (EP/2.5MPF) and (EP/1.25MPF) composites were carried out at different weight percentages of pumpkin fibers. SEM and EDS techniques were employed to fix the microstructure and the elemental composition of (EP/2.5MPF) and (EP/1.25MPF) composites, respectively. The internal structure of the composites has been linked with their macroscopic characteristics, such as the color degree of natural gelcoats and their mechanical and thermal properties.
Background: Debonding and fracture of artificial teeth from denture bases are common clinical problem, bonding of artificial teeth to heat cure acrylic and high impact heat cure acrylic denture base materials with autoclave processing method is not well known. The aim of this study was to evaluate the effect of autoclave processing method on shear bond of artificial teeth to heat cure denture base material and high impact heat cure denture base material. Materials and methods: Heat polymerized (Vertex) and high impact acrylic (Vertex) acrylic resins were used. Teeth were processed to each of the denture base materials after the application of different surface treatments. The sample (which consist of artificial tooth attached to the dentur
... Show MoreBackground: Change in palatal vault shape and Reinforcement of high impact acrylic denture base resin may in turn affect the dimensional accuracy of acrylic resin and affecting the fitness of the denture.This study evaluated tostudy the effect of fiber reinforcement for high-impact acrylic resin denture base with different palatal vault shapes on adaptation or gap space between the denture base and the stone cast and compare with non-fiber reinforcement and effect of palatal vault shapes on adaptation of non-reinforced and fiber reinforced high impact denture base acrylic resin Material and method: Three different palatal vault shapes were prepared on standard casts using CNC (computer numerical control) machine. 60 samples of heat polymeri
... Show MoreThe D.C. electrical properties of poly (ethylene oxide)/MgCl2 composites were investigated as a function of different MgCl2 filler concentrations (0, 5, 10, 15 and 20 wt.%) and different temperatures in the range (276–333)o K at three different polarizing fields. Resistivity:ï² and dc Conductivity: σ dc were measured, and the activation energy: Ea of the thermal rate-process of the electrical conduction was investigated. It was found that the current-voltage measurement results exhibited Ohmic resistance behavior, the composites exhibit negative temperature reliance of resistivity and enhancement in the D.C. electrical conductivity with both temperature and MgCl2 concentration. The determined activation energy was found to
... Show MoreIn this research, an enhancement in lubricating, rheological, and filtration properties of unweighted water-based mud is fundamentally investigated using XC polymer NPs with 0.2gm, 0.5gm, 1gm, 2gm, and 4gm concentrations. Bentonite, that had been used in the preparation of unweighted water-based mud, was characterized using XRF-1800 Sequential X-ray Fluorescence Spectrometer, XRD-6100/7000 X-ray Diffractometer, and Malvern Mastersizer 2000 particle size analyzer, respectively. Lubricating, rheology and filtration properties of unweighted water-based mud were measured at room temperature (35°C) using OFITE EP and Lubricity Tester, OFITE Model 900 Viscometer, and OFITE Low-Pressure Filter Press, respectively. XC Polymer N
... Show MoreThe chemical additives used to enhance the properties of drilling mud cause damage to humans and the environment. Therefore, it is necessary to search for alternative additives to add them to the drilling mud. Thus, this study investigates the effects of pomegranate peel and grape seed powders as natural waste when added to un-weighted water-based mud. The test includes measurements of the rheological properties and filtration, as well as the alkanity and density of the drilling mud. The results showed a decrease in PH values with an increase in the concentrations of pomegranate peel or grapeseed, and a decrease in mud density with an increase in powders of pomegranate peel and grape seed concentrations that resulted f
... Show MoreIn this work, the emission spectra and atomic structure of the aluminum target had been studied theoretically using Cowan code. Cowan code was used to calculate the transitions of electrons between atomic configuration interactions using the mathematical method called (Hartree-Fock). The aluminum target can give a good emission spectrum in the XUV region at 10 nm with oscillator strength of 1.82.
The hydrodynamic properties of laser produced plasma (LPP) were investigated for the purpose of creating a light source working in the EUV region. Such a light source is very important for lithography (semiconductor manufacturing). The improved MEDUSA (Med103) code can calculate the plasma hydrodynamic properties (velocity, electron density,
In this research, the study of thermal treating by laser, plasma glow discharge and tubular furnace on Ti-6Al-4V alloy coated with hydroxyapatite by methods of dip coating and electrophoretic deposition .A group of samples was coated by dip coating and another group was coated by electrophoretic deposition. The first group was treated by pulse laser 10 (mJ) as energy for samples from both coating with uniform distributed pulses on every single sample surface, The second thermal treating was made by plasma glow discharge in a locally made system with argon atmosphere, 600 Volt , and 6 cm distance between the electrodes, The third treating was made by tubular furnace in air atmosphere and 400 °C for 1 hour duration. T
... Show MoreThe loose sand is subject to large settlement when it is exposed to high stresses. This settlement is due to the nature of the high drainage of sand, which displays foundations and constructions to a large danger. The densification of loose sandy soils is required to provide sufficient bearing capacity for the structures. Thus soil stabilization is used to avoid failure in the facilities. Traditional methods of stabilized sandy soil such as fly ash, bituminous, and cement often require an extended curing period. The use of polymers to stabilize sandy soils is more extensive nowadays because it does not require a long curing time in addition to being chemically stable. In this study, the effect of adding different percent
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