Scleral acrylic resin is widely used to synthesize ocular prosthesis. However, the properties of this material change over time, thus requiring the prosthesis to be refabricated. Many studies were conducted to improve these properties by reinforcing this material with nanoparticles. This study aims to evaluate the effect of silver nanoparticle powder on the mechanical properties (transverse flexural strength, impact strength, shear bond strength, surface microhardness, and surface roughness) of scleral acrylic resin used for ocular prostheses. Two concentrations were selected from the pilot study and evaluated for their effects on scleral acrylic resin properties. According to the pilot study, 0.01 and 0.02wt% AgNPs powder improved the transverse flexural strength, microhardness, and surface roughness compared with other percentages. The specimens in the main study were divided into (3) main groups, (50) specimens without additives (control group A), (50) experimental specimens (with 0.01wt% AgNPs group B), and (50) experimental specimens (with 0.02 wt% AgNPs group C). Each group was subdivided into (5) equal subgroups depending on the tests used. The data were studied using one way ANOVA and post hoc LSD test. At 0.01 wt% AgNPs addition, the mean values of transverse flexural strength insignificantly increased (p> 0.05), and those of impact strength and shear bond strength significantly increased (p< 0.05) compared with those of the control group. At 0.02 wt% AgNPs addition (group C), the mean value of transverse flexural strength significantly increased (p< 0.05), that of impact strength insignificantly increased (p> 0.05), and that of shear bond strength increased with high significance (p< 0.01) compared with those of the control group. Group C showed insignificant increase in the mean values of transverse flexural strength, impact strength, and shear bond strength (p. 0.05) compared with group B. The scleral acrylic resin added with 0.01 and 0.02 wt% AgNPs showed insignificant increase in microhardness and insignificant decrease in surface roughness. The addition of AgNPs powder in both concentrations improved the mechanical properties of scleral acrylic resin used for ocular prostheses.
In our research, we seek to shed a light on one of the most important and sensitive issues, namely, the Sufi influence in the Iraqi novel through the lame maqam of the novelist Jumaa Al-Lami, the Sufi discourse contains many semantic paradoxes between the text's apparent pronunciation and its interpretation of the format and the context that produced these patterns, and incited them, which concludes different results from the prevailing provisions and fixed ideas from the narrative text.The Arabic and Iraqi novel in particular became inspired by the power of Sufi discourse by talking about several Sufi figures by referring to it openly, or implicitly inspired by unauthorized concealment, in employing some of the ideas, or summoning
... Show MoreThe natural polyphenolic compound that cinnamon contains is well known for its various biological activities, a broad variety of pharmacological and therapeutic properties. Diversified biomedical and pharmacological applications benefit from organic nanoparticles with controlled properties. Bioactive and non-toxic, cinnamon nanoparticles (CNPs) can be effective antibacterial agents. Driven by this idea, we prepared spherical CNPs using liquid (PLAL) pulse laser ablation technique and defined those NPs. Using Q-switched Nd : YAG With a wavelength of 1064 nm pulse laser of constant energy 500 mj , And different laser pulses ( 250 , 500 , 750 , 1000 ) pulse /sec a pure cinnamon target submerged in
... Show MoreDuring the last quarter century, many changes have taken place in the tanks industry and also in the materials that used in its production، while concrete is the most suitable material where concrete tanks has the benefits of strength, long service life and cost effectiveness. So, it is necessary improvement the
conventional concrete in order to adapt the severe environment requirements and as a result high
performance concrete (HPC) was used. It is not fundamentally different from the concrete used in the past, although it usually contains fly ash, ground granulated blast furnace slag and silica fume, as well as
superplasticizer. So, the content of cementitious material is high and the water/cement ratio is low. In this
stu
No-fine concrete (NFC) is cellular concrete and it’s light weight concrete produced with the exclusion of sand from the concrete. This study includes the mechanical properties of lightweight reinforced by steel fiber, containing different proportions of steel fiber. This study was done using number of tests. These tests were density, compressive strength, flexural strength and absorption. These tests of the molds at different curing time. The results of tests that implication of fiber to No. fine concrete did not affect significantly on the compressive strength, While the flexural strength were gets better. Results explained that, the flexural strength of (1%) fiber No- fine concrete molds are four times that of the reference mold
... Show MoreAs an alternative to Ordinary Portland Cement (OPC), the alkali-activated binders have been developed with better technical characteristics and more extended durability. The Alkali-Activated Iraqi Natural Pozzolans (AANP) could produce geopolymer cementation building materials and make them ecologically acceptable. The primary advantage of geopolymer cement is that it has a lower environmental effect that contributes to it. The engineering characteristics of geopolymer concrete produced using activated Iraqi natural Pozzolan are summarized in this research. The mechanical properties, modulus of elasticity, and ultrasonic pulse velocity of various concrete mixes were determined via exp
The present work shows a theoretical results that have been used the functional Hybrid of three parameters Lee-Yang-Parr (B3LYP) of the quantum mechanical approach for density functional theory with (Spanish Initiative for Electronic Simulations with Thousands of Atoms) SIESTA code. All calculations were carried out employing the used method at the Gaussian 09 package of programs. It was reported the main point for research on dominance of the bandgap of elongated pi-conjugated molecules by using different chemical groups replacing hydrogen atom in the most molecules that used in this work. The side groups creates another factor that controls the value of the band gap. The dihedral angle between the two pheny
... Show MoreThe dielectric constant of most polymers is very low; the addition of TiO2 particles into the polymers provides an attractive and promising way to reach a high dielectric constant. Polymer-based materials with a high dielectric constant show great potential for energy storage applications. Four samples were prepared, one of them was polyurethane (PU) and the other were PU with different weight percent (wt %) of TiO2 (0.1, 0.2, 0.3) powder AFM test was used to distinguish the nanoparticles. The result shows that the most shape of these nanoparticles are spherical and the roughness average is 0.798 nm. The dielectric properties were measured for all samples before and after the exposure to the UV radiation. The result illustrates that the
... Show MoreAs an alternative to Ordinary Portland Cement (OPC), the alkali-activated binders have been developed with better technical characteristics and more extended durability. The Alkali-Activated Iraqi Natural Pozzolans (AANP) could produce geopolymer cementation building materials and make them ecologically acceptable. The primary advantage of geopolymer cement is that it has a lower environmental effect that contributes to it. The engineering characteristics of geopolymer concrete produced using activated Iraqi natural Pozzolan are summarized in this research. The mechanical properties, modulus of elasticity, and ultrasonic pulse velocity of various concrete mixes were determined via experimental study. The impact of essential variables like w
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