Background: The incorporation of rubber has not been entirely successful because it can have detrimental effects on the transverse Strength and hence the rigidity of the denture base. Materials and methods: Zirconium oxide nanoparticales were coated with a layer of trimethoxysilylpropylmethacrylate (TMSPM) before sonication in monomer (MMA) with the percentages 3% by weight then mixed with powder using conventional procedure.(100) samples were prepared and divided into five groups according to the test performed ,Each group consisted of 20 specimens and these were subdivided into 2 groupsGroup (A): control group (10 specimens of high impact acrylic resin without zirconium oxide) and Group (B):zirconium oxide group(10 specimens of high impact acrylic resin with 3% wt zirconium oxide).The tests conducted were impact strength, transverse strength, indentation hardness(shore D), surface roughness, water sorption and solubility. The results were statistically analyzed using Dunntt t-test. Results: Highly significant increase in impact strength and transverse strength occurred with the incorporation of 3% wt Zirconium oxide nanofiller. A highly significant increase in surface hardness, but the water sorption and solubility were significantly decreased with the addition of silanized (ZrO2) Nano particles compared with the control group.no significant statistical difference in surface roughness. Conclusions: The addition of silanized ZrO2 Nano particles to high impact heat cure acrylic resin material improves the impact strength, transverse strength and surface hardness of high-impact heat-cure acrylic resin at the same time this addition decreases water sorption and solubility. On the other hand there was no change in surface roughness with the addition of 3% wt of silanized ZrO2Nano particles.
The aim of the present research is concerned with study the effect of UV radiation on the optical properties at wavelengths 254, 365 nm of pure PC and anthracene doping PC films prepared using the cast method for different doping ratio 10-60 mL. Films of pure PC and anthracene doping PC were aged under UV radiation for periods of up to 360 h. It found that the effect of UV radiation at wavelength 254 nm on the optical properties is great than the effect of UV radiation at wavelength 365 nm. Also, it found that the optical energy gap of pure PC and anthracene doping PC films is stable against radiation.
Matrix acidizing is a good stimulation process in which acid is introduced into the reservoir near the wellbore area via the wellbore or coil tubing. In the oil industry, formation damage is a prevalent problem. Bypassing wellbore damage by producing wormholes in carbonate reservoirs is the main purpose of acidizing the matrix of the formation. When doing lab tests, scientists are looking for a wormhole-inducing injection rate that can be used in the field. Meantime the ongoing works on the Ahdeb oil field's Mishrif reservoir, several reports have documented the difficulties encountered during stimulation operations, including high injection pressures that make it difficult to inject acid into the reservoir formation; and only a few
... Show MoreIn this article the nanoparticles synthesis of ZnO (Nps) by using the precipitation method at concentrations range (0.5, 0.25, 0.125, 0.0625, 0.03125) mg/mL and then activity was examined against Streptococcus spp that causing dental caries in vitro by well diffusion method, find these concentrations effected in these bacteria and better concentration is 0.03125. ZnO Nps were characterization by EDS to prove this particles are ZnO, and also characterized by atomic force microscope (AFM), X-ray Diffraction (XRD) and TEM, from these technic found that the average size about 30.52 nm and hexagonal shape. The UV-visible result reveals that the large band is observed at 340.8 nm, Zeta potential show that the surface charge is 30.19 mv an
... Show MoreCurrent studies interested on the biosynthesis of zinc oxide nanoparticles (ZnO-NPs) using hot plants extracts of Allium sativum and characterization of them using: Atomic Force Microscopy (AFM), X-ray diffractions (XRD), Fourier Transform Infrared Spectroscopy (FT- IR), UV–visible spectral and Hot stage. The results found that all NPs are had nano-size. ZnO NPs was produced by four procedures using hot extract of Allium sativum. The average diameters were: 101.59 nm, 110.33 nm, 75.69 nm, 88.67 nm for first, second, third and fourth procedures respectively compared with 47.57 nm for standard NPs. The Roughness averages (Ra) were: 10.8 nm, 6.83 nm, 13.8 nm, 0.541 nm for first, second, third and fourth respectively. The Root mean square (Sq
... Show MoreThe two-dimensional transient heat conduction through a thermal insulation of temperature dependent thermal properties is investigated numerically using the FVM. It is assumed that this insulating material is initially at a uniform temperature. Then, it is suddenly subjected at its inner surface with a step change in temperature and subjected at its outer surface with a natural convection boundary condition associated with a periodic change in ambient temperature and heat flux of solar radiation. Two thermal insulation materials were selected. The fully implicit time scheme is selected to represent the time discretization. The arithmetic mean thermal conductivity is chosen to be the value of the approximated thermal conductivity at the i
... Show MoreMany designs have been suggested for unipolar magnetic lenses based on changing the width of the inner bore and fixing the other geometrical parameters of the lens to improve the performance of unipolar magnetic lenses. The investigation of a study of each design included the calculation of its axial magnetic field the magnetization of the lens in addition to the magnetic flux density using the Finite Element Method (FEM) the Magnetic Electron Lenses Operation (MELOP) program version 1 at three different values of current density (6,4,2 A/mm2). As a result, the clearest values and behaviors were obtained at current density (2 A/mm2). it was found that the best magnetizing properties, the high
... Show MoreExpansive soil spreads in Iraq and some countries of the world. But there are many problems can be occurred to the structures that built on, so we must study the characteristics of these soils due to the problems that may be caused to these structures which built on these kinds of soil and then study the methods of treatment. The present study focuses on improving the geotechnical properties of expansive soils by treating it Metakaolin(M). Metakaolin (M) has never been used before as an improvement material for stabilizing the expansive soil . Metakaolin is a pozzolanic material. It’s obtained by calcination of kaolinite clay at temperatures from 700°C to 800°C. Kaolin chemical composition is
... Show MoreNiO nanoparticle synthesis by chemical method and characterized by XRD with crystal size 11.72
nm and grain size 13 nm from FESEM image also NiO micro used ,two NiO as an additive to evaluate the
possibility of producing photodegradable polymers, the practical application of solid-phase photocatalytic
degradation of polyvinyl chloride (PVC- NiO composite films) was investigated. PVC has a negative impact
on the environment since its polymer degrades slowly, yet it has a wide range of industrial applications and
the amount used shows no evidence of diminishing use. Thus, a synthesis of modified PVC- NiO micro and
nano has been studied with 0, 50, 100, 150, 200, 250, and 300 (hours) as irradiation time a
The uniform flow distrbiution in the multi-outlets pipe highly depends on the several parameters act togather. Therefor, there is no general method to achieve this goal. The goal of this study is to investigate the proposed approach that can provide significant relief of the maldistribution. The method is based on re-circulating portion of flow from the end of the header to reduce pressure at this region . The physical model consists of main manifold with uniform longitudinal section having diameter of 152.4 mm (6 in), five laterals with diameter of 76.2 mm (3 in), and spacing of 300 mm. At first, The experiment is carried out with conventional manifold, which is a closed-end. Then, small amount of water is allowed
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