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.
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... Show MoreThe research aims to evaluate the selected projects from the water Department of Baghdad, according to a standard for total quality management and to achieve this goal , adopted the case study method to get to know how close or turn away those projects in the management of Standard Malcolm Baldrige Award for Excellence in Quality Management its comprehensive one scales the world's most famous in this area , in order to draw a general framework to evaluate how project management can benefit from this approach to modern management , input from the entrances of the comprehensive management reform and development.
Be standard Malcolm Baldrige Award of several elements: - leadership , strategic planning , foc
... Show MoreNew Schiff base [3-(3-acetylthioureido)pyrazine-2-carboxylic acid][L] has been prepared through 2 stages, the chloro acetyl chloride has been reacting with the ammonium thiocyanate in the initial phase for producing precursor [A], after that [A] has been reacting with the 3-amino pyrazine-2-carboxilic acid to provide a novel bidentate ligand [L], such ligand [L] has been reacting with certain metal ions in the Mn(II), VO(II), Ni(II), Co(II), Zn(II), Cu(II), Hg(II), and Cd(II) for providing series of new metal complexes regarding general molecular formula [M(L)2XY], in which; VO(II); X=SO4,Y=0, Co(II), Mn(II), Cu(II), Ni(II), Cd(II), Zn(II), and Hg(II); Y=Cl, X=Cl. Also, all the compounds were characterized through spectroscopic techniques [
... Show MoreEMS in accordance with ISO 14001: 2015 is considered an entry point to reduce environmental impacts, especially the effects resulting from the oil industry, which is the main source of environmental pollution and waste of natural resources, since the second revision of the standard took place in September 2015. The problem of the research was manifested in the weakness in understanding the correct guidelines that must be followed in order to obtain and maintain the standard. The purpose of this research was to give a general picture of what is behind ISO14001:2015 and how it is possible to create a comprehensive base for understanding its application by seeking the gap between the actually achieved reality, standards requirements
... Show MoreThe aim of this study is for testing the applicability of Ramamoorthy and Murphy method for identification of predominant pore fluid type, in Middle Eastern carbonate reservoir, by analyzing the dynamic elastic properties derived from the sonic log. and involving the results of Souder, for testing the same method in chalk reservoir in the North Sea region. Mishrif formation in Garraf oilfield in southern Iraq was handled in this study, utilizing a slightly-deviated well data, these data include open-hole full-set logs, where, the sonic log composed of shear and compression modes, and geologic description to check the results. The Geolog software is used to make the conventional interpretation of porosity, lithology, and saturation. Also,
... Show MoreIn this golden age of rapid development surgeons realized that AI could contribute to healthcare in all aspects, especially in surgery. The aim of the study will incorporate the use of Convolutional Neural Network and Constrained Local Models (CNN-CLM) which can make improvement for the assessment of Laparoscopic Cholecystectomy (LC) surgery not only bring opportunities for surgery but also bring challenges on the way forward by using the edge cutting technology. The problem with the current method of surgery is the lack of safety and specific complications and problems associated with safety in each laparoscopic cholecystectomy procedure. When CLM is utilize into CNN models, it is effective at predicting time series tasks like iden
... Show MoreBecause of the conservation problems causes by the existence of water hyacinth (W.H) as an watery plant in water bodies of Iraq, our study aimed to make use of (W.H) by isolation of microcrystalline cellulose, and a new method of preparation of Nano crystalline cellulose. Microcrystalline cellulose was produced using base bleaching method by sodium hypochlorite [NaOCl] to remove unorganized region of cellulose and lignin to create particles comprising of micro crystal and preparing of Nano crystalline cellulose from microcrystalline cellulose by acid hydrolysis and ultrasonic treatment. The Nano crystalline and microcrystalline cellulose characterized by AFM, FTIR, XRD and TGA. FT-IR spectra of microcrystalline cellules and Nano cr
... Show MoreQuinolones L1 (ciprofloxacin) are manufactured wide range anti-infection agents with great oral ingestion and magnificent bioavailability. Because of the concoction capacities found on their core (a carboxylic corrosive capacity at the 3-position) and much of the time an essential piperazinyl ring (or anothertN-heterocycle) at the 7-positionh and a carbonylvoxygenc atomi atothel 4-positioni) quinolones bind metal particlesiframing buildings which can go about as bidentate. Bidentateiligands L2=2-phenyl-2-(P-methoxy anilinee) acetonitrilel was set up by the response of Primiryiaminejwithjbenzaldehyde, in nearness of potassiumbcyanidej and acidicimedia . Theimetalledifices were portrayed by the miniaturized scale component examination (C.H
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