Resilient polymeric materials such as silicone elastomers are currently used for maxillofacial prostheses construction but the strength of these materials and their clinical performance need to be optimized with the addition of reinforcing fillers. This study investigates the effect of zirconia nanopowder addition on tear strength, tensile strength, elongation at break, Shore A hardness, surface roughness and cytotoxicity of VST-50 maxillofacial silicone. Silicone base was mixed with different amounts (1%, 2% and 3%) of zirconia nanopowder using a vacuum mixer. Silicone without filler was used as control for comparison. Scanning Electron Microscopy and Atomic Force Microscopy were utilized to assess the efficiency of high-shear vacuum mixing as filler dispersion method and the surface topography, respectively. Both SEM and AFM images showed that the zirconia nanopowder were distributed fairly well within the polymer. Statistically, highly significant increase in tear strength, tensile strength and hardness with non-significant decrease in elongation at break and non-significant increase in surface roughness were seen with 1% and 2% groups. Whereas with 3% group, there was significant improvement in tear strength, tensile strength and hardness but there was significant undesirable decrease in elongation and increase in roughness. Cytotoxicity test revealed that the addition of zirconia nanopowder was nontoxic to Rat Embryonic Fibroblast (REF) cells and there was non-significant change in the cell viability of all study groups after 24- and 72-hours incubation periods. In conclusion, the addition of 2% by weight nano zirconia to VST-50 maxillofacial silicone could be beneficial in enhancing its performance.
The main objective of the paper is to study the possibility of erecting 2 MW wind turbine in the south of Iraq (Barjisiah site) by utilizing WAsP model. Wind potential and output predicted the power of WT at a supposed site was calculated. The results for proposed WT showed the WT has a weak performance due to its high capacity and low potential of wind speeds at this site. So, the WT will provide power for a limited time during the year due to its operating at the zone under the rated wind speed.
Objective(s):To evaluate the quality of life among secondary and to find out the relationship between students'quality of life and their socio-demographic characteristics of age, gender, residence, marital status, father's and mother's education, and family financial status in Kirkuk City. Methodology: A cross-sectional study is conducted on (100) studentwho are boys and girls aged(13 to 24) years old. These subjects are studying at secondary schools in Kirkuk City.The study is carried out at secondary schools in Kirkuk City from 7th July 7th 2014 to May 7th 2015. A questionnaire is constructed for the purpose
Objective(s): To evaluate nurses' knowledge toward pain management of leukemic child in oncology wards
how were receiving chemotherapy.
Methodology: A descriptive study was conducted in two hospitals on (40) nurses, who provided care for the
children with leukemia in oncology wards (2) hospitals (Children Welfare Teaching Hospital and Child’s Central
Teaching Hospital) in Baghdad city from October 2010 up to the 27th of October 2011 for the purpose of
evaluating their knowledge towards pain management for leukemic child. A purposive "non-probability
sample" was selected that consisted of (40) nurse who are working in oncology wards. A questionnaire format
was used which consist of (2) parts, the first part includes
In this work, we are obviously interested in a general solution for the calculation of the image of a single bar in partially coherent illumination. The solution is based on the theory of Hopkins for the formation of images in optical instruments in which it was shown that for all practical cases, the illumination of the object may be considered as due to a self – luminous source placed at the exit pupil of the condenser , and the diffraction integral describing the intensity distribution in the image of a single bar – as an object with half – width (U0 = 8 ) and circular aperture geometry is viewed , which by suitable choice of the coherence parameters (S=0.25,1.0.4.0) can be fitted to the observed distribution in various types of mi
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The research aims to achieve defining the concept of environmental quality and associated costs. Studying the impact of environmental quality costs on the performance of economic units. Measuring the relationship between environmental quality and environmental performance of the units. Where the research problem is represented in the weak awareness of some economic units of the importance of environmental quality costs and their impact on evaluating environmental performance, and this leads to neglecting environmental considerations and not improving environmental performance effectively, which negatively affects the en
... Show MoreThirty water sample of wells, and three samples of springs from the upper most aquifer, as well as four samples from Lesser Zab River in Koi Sanjaq Basin, Erbil governorate of northern Iraq was collected and physically and chemically were analyzed. Physical analysis includes temperature, hydrogen ion concentration (pH), Electrical Conductivity (EC), Total Dissolved Solid (TDS), and Turbidity, whereas the geochemical analysis included concentration determines of the major, minor and trace elements. Chemical classification of the present samples using of chadha diagram explain that ( 95% ) of them located within field 5 and 6 whereas the rest (5%) are located in the field 8. According to Iraqi [9] and WHO [10] standers, most of the samples
... Show MoreA lot of previous studies are concerned with the evaluation of the anti-inflammatory activity of medicinal plants because it considered cheap and are believed to possess minimal side effects. Leucaena leucocephala didn’t evaluate globally for its anti-inflammatory effect yet though some of it’s already separated and identified secondary metabolites were studied and proved to exert many pharmacological activities besides their effect on lowering the pro-inflammatory cytokines like TNF-α and IL-6. So, there was an interest to evaluate the biological effect of Leucaena leucocephala as a novel anti-inflammatory agent was the first motivation to start an in vivo study using a rat population. The N-butanol and ethyl acetate extracts were cho
... Show MoreThe thermal performance of indirect expansion solar assisted heat pump, IX-SAHP, was investigated experimentally under Iraqi climate. An Indirect-Solar Assisted Heat Pump system was designed, built, instrumented and tested. Experimental tests were conducted by varying the controlling parameters to investigate their effects on the thermal performance of the IX-SAHP such as cooling water flow rate, heating water flow rate, ambient temperature and solar radiation intensity. The investigation covered values of cooling water flow rate of (2, 3, 4, 5 l/min) and heating water flow rate of (2, 3, 4, 5 l/min) under meteorological condition of Baghdad from November 2014 to January 2015.
The results indicated that the performance of the IX-
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