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.
An analytical form of the ground state charge density distributions
for the low mass fp shell nuclei ( 40 A 56 ) is derived from a
simple method based on the use of the single particle wave functions
of the harmonic oscillator potential and the occupation numbers of
the states, which are determined from the comparison between theory
and experiment.
For investigating the inelastic longitudinal electron scattering form
factors, an expression for the transition charge density is studied
where the deformation in nuclear collective modes is taken into
consideration besides the shell model space transition density. The
core polarization transition density is evaluated by adopting the
shape of Tass
The monitoring weld quality is increasingly important because great financial savings are possible because of it, and this especially happens in manufacturing where defective welds lead to losses in production and necessitate time consuming and expensive repair. This research deals with the monitoring and controllability of the fusion arc welding process using Artificial Neural Network (ANN) model. The effect of weld parameters on the weld quality was studied by implementing the experimental results obtained from welding a non-Galvanized steel plate ASTM BN 1323 of 6 mm thickness in different weld parameters (current, voltage, and travel speed) monitored by electronic systems that are followed by destructive (Tensile and Bending) and non
... Show MoreThe population density of the insect on Alorat and fruits located in the lower part of the tree more than the middle part of the plant and insect in one place and demonstrates that there is a nest there were conducted laboratory and field studies on citrus Hsasahanwaa and the Alvdaúaa distribution of cortical insect yellow ....
The research issue and its importance concentrate on the importance of choosing and
preparing the kindergarten's teacher educationally ,psychologically and artistically ,and other
aspects because of their need for several skills such as the drawing skill for kindergarten
curriculums include a various artistic experiences and activities as well as for the drawing
importance for the child .And from this, the research goals raise from to prepare a test that
measures the drawing skill for kindergarten students and measure the drawing skill in all four
kindergarten students at the kindergarten department and recognize the differences level for
these students . In order to achieve the first goal in the research ,the resear
Computations of the relative permeability curves were made through their representation by two functions for wetting and nonwetting phases. Each function contains one parameter that controls the shape of the relative permeability curves. The values of these parameters are chosen to minimize an objective function, that is represented as a weighted sum of the squared differences between experimentally measured data and the corresponding data calculated by a mathematical model simulating the experiment. These data comprise the pressure drop across core samples and the recovery response of the displacing phase. Two mathematical models are constructed in this study to simulate incompressible, one-dimensional, two-phase flow. The first model d
... Show Moreالمستخلص
يهدف البحث إلى وضع إطار معرفي ومفاهيمي شامل لموضوع البحث, واغناء القارئ والمستفيد بالمعلومات الوافية عنه وتقليص الفجوات المعرفية للمهتمين به وقياس مدى ما هو متوفر وغير متوفر من المتطلبات الأساسية والضرورية لإنشاء صناديق التحوط في البيئة العراقية, وتمثلت صناديق التحوط بالمتغير الرئيس للبحث اما المتغيرات الفرعية فشملت (المتطلبات المالية, المتطلبات البشرية, البيئة التشريعية, الب
... Show MoreIncreasing material prices coupled with the emission of hazardous gases through the production and construction of Hot Mix Asphalt (HMA) has driven a strong movement toward the adoption of sustainable construction technology. Warm Mix Asphalt (WMA) is considered relatively a new technology, which enables the production and compaction of asphalt concrete mixtures at temperatures 15-40 °C lower than that of traditional hot mix asphalt. The Resilient modulus (Mr) which can be defined as the ratio of axial pulsating stress to the corresponding recoverable strain, is used to evaluate the relative quality of materials as well as to generate input for pavement design or pavement evaluation and analysis. Based on the aforementioned preface, it is
... Show MoreThe present work describes the adsorption of Ba2+ and Mg2+ions from aqueous solutions by activated alumina in single and binary system using batch adsorption. The effect of different parameters such as amount of alumina, concentration of metal ions, pH of solution, contact time and agitation speed on the adsorption process was studied. The optimum adsorbent dosage was found to be 0.5 g and 1.5 g for removal of Ba2+ and Mg2+, respectively. The optimum pH, contact time and agitation speed, were found to be pH 6, 2h and 300 rpm, respectively, for removal of both metal ions. The equilibrium data were analyzed by Langmuir and Freundlich isotherm models and the data fitted well to both isotherm modes as indicated by higher correlation of deter
... Show MoreThe aim of this paper is to determine the role of job engagement in the Iraqi Residency Affairs Directorate and its impact on employees, as the job engagement variable based on the Rich’s model included dimensions of cognitive engagement, emotional engagement and physical engagement. This variable has been studied in the Directorate of Residence Affairs which are one of the specialized directorates in the Iraqi Ministry of Interior. This study relied on a questionnaire as a main tool for measuring and collecting data based on the random sampling method . The sample size included 206 individuals among 400 individuals. However, the respondents were 190 whereas the final
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