Background: During acrylic resin processing, the mold must be separated from the surface of the gypsum to prevent liquid resin from penetrating into the gypsum, and water from the gypsum seeping into the acrylic resin. For many years, tin foil was the most acceptable separating medium, and because it's difficult to apply, a tin-foil substitute is used. In this study, olive oil is used as an alternative to tin foil separating medium for first time, and evaluating its effect as a separating medium on some mechanical properties such as (indentation hardness and transverse strength) of acrylic resins denture base comparing it with those processed using tin-foil and tin foil substitute such as (cold mold seal) separating medium. Materials and Methods: One hundred Twenty four acrylic resins samples (124) were prepared falling in two main groups: (heat and cold-cured acrylic denture base resins), for each group three types of separating medium were used and five tests (10 samples) for each test were carried out, and (4) samples for the chemical composition. Results: Tin foil is one of the most satisfactory separating media in getting the best properties when using it as a separating medium, while, a statistically no-significant difference have been noticed between olive oil and cold-mold seal samples concerning mechanical properties of tested groups. Infrared spectroscopy analysis showed that, no changes were found in the chemical composition of both heat and cold-cured acrylic resins denture base after using olive oil as a separating medium. Conclusion:The present study concluded that olive oil may be used as a substitute for tin foil and cold – mold seal separating medium in processing both heat and cold – cure acrylic resin denture base.
This study seeks to identify the role that the leadership trend plays in the management of health institutions in Iraq and its impact on improving the quality of the health service provided by analyzing some opinions of affiliates working in the Iraqi health sector where a survey list was used as a main tool for collecting primary data, as it was subjected to this analysis ( 60) of the medical staff, of whom (40) are doctors and (20) are affiliated with the rank of assistant physician, and (60) members of the administrative cadre have undergone their various job ranks and administrative specializations (department manager, auditor, observer, accountant, statistician, secretary). Reliance on statistical software (spss) in data ana
... Show MoreNatural fibers and particles reinforced composites are being broadly used due to their bio and specific properties such as low density and easy to machine and production with low cost. In this work, water absorption and mechanical properties such as tensile strength, flexural strength and impact strength of recycled jute fibers reinforced epoxy resin were enhanced by treating these fibers with alkaline solution. The recycled jute fibers were treated with different concentration of (NaOH) solution at (25 0C) for a period of (24) hours. From the obtained results, it was found that all these properties are improved when fibers treated with (7.5wt% NaOH) related to untreated fibers. Conversely, the mentioned properties of composit
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The importance of specifying proper aggregate grading for achieving satisfactory performance in pavement applications has long been recognized. To improve the specifications for superior performance, there is a need to understand how differences in aggregate gradations within the acceptable limits may affect unbound aggregate base behavior. The effects of gradation on strength, modulus, and deformation characteristics of high-quality crushed rock base materials are described here. Two crushed rock types commonly used in constructing heavy-duty granular base layers in the State of Victoria, Australia, with three different gradations each were used in this study. The gradations used represent the lower, medium, and upper gradation li
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The current Iraqi standard specifications for roads and bridges allowed the prepared Job-Mix Formula for asphalt mixtures to witness some tolerances with regard to the following: coarse aggregate gradation by ± 6.0 %, fine aggregate gradation by ± 4.0 %, filler gradation by ± 2.0 %, asphalt cement content by ± 0.3 % and mixing temperature by ± 15 oC. The objective of this work is to evaluate the behavior of asphalt mixtures prepared by different aggregates gradations (12.5 mm nominal maximum size) that fabricated by several asphalt contents (40-50 grade) and various mixing temperature. All the tolerances specified in the specifications are taken into account, furthermore, the zones beyond these tolerances
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This study compared the effects of citric acid (CA) derived from microbial fermentation using Aspergillus niger (400 mg kg-1) and natural extraction from Citrus limon (400 mg kg1) in albino mice. Parameters assessed included cytogenetic damage via the micronucleus (MN) assay, immunological response through immunoglobulin (IgA, IgG, IgM) titers, and hepatoprotective activity based on liver enzyme levels (AST, ALT, ALP) and histopathological inves tigation. Mice were divided into six groups (n=10/group) as follows: (1) negative control, (2) carbon tetrachloride (CCl₄ 0.02%), (3) lemon CA, (4) A. niger, (5) CCl₄ + lemon CA, and (6) CCl₄ + A. niger CA. The CCl4 group exhibited a significantly higher MN frequency (0.06 ± 0.008) compa
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Some coordination complexes of Co(ІІ), Ni(ІІ), Cu(ІІ), Cd(ІІ) and Hg(ІІ) are reacted in ethanol with Schiff base ligand derived from of 2,4,6- trihydroxybenzophenone and 3-aminophenol using microwave irradiation and then reacted with metal salts in ethanol as a solvent in 1:2 ratio (metal: ligand). The ligand [H4L] is characterized by FTIR, UV-Vis, C.H.N, 1H-NMR,13C-NMR, and mass spectra. The metal complexes are characterized by atomic absorption, infrared spectra, electronic spectra, molar conductance, (C.H.N for Ni(ІІ) complex) and magnetic moment measurements. These measurements indicate that the ligand coordinates with metal (ІІ) ion in a tridentate manner through the nitrogen and oxygen atoms of the ligand, octahed
... Show MoreSome coordination complexes of Co(??), Ni(??), Cu(??), Cd(??) and Hg(??) are reacted in ethanol with Schiff base ligand derived from of 2,4,6- trihydroxybenzophenone and 3-aminophenol using microwave irradiation and then reacted with metal salts in ethanol as a solvent in 1:2 ratio (metal: ligand). The ligand [H4L] is characterized by FTIR, UV-Vis, C.H.N, 1H-NMR,13C-NMR, and mass spectra. The metal complexes are characterized by atomic absorption, infrared spectra, electronic spectra, molar conductance, (C.H.N for Ni(??) complex) and magnetic moment measurements. These measurements indicate that the ligand coordinates with metal (??) ion in a tridentate manner through the nitrogen and oxygen atoms of the ligand, octahedral structures
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