Background: Imprelon® Biostar foils are new alternative tray material that has become increasingly popular because oftheir several advantages. Also, (Duran®) is another type of Biostar foils which is used in splint therapy. This study assessed some mechanical properties of these two types Biostar sheets in comparison with some types of acrylic resins used for construction of trays and splints. Materials and Methods: A total of 150 specimens were prepared, 30 specimens for each test, 10 for each group material in order to assess some mechanical properties of the Imprelon® Biostar foil (dimension stability, surface roughness and shear bond strength of Imprelon® materialto zinc oxide impression material) and compare them to that of the other tray materials (autopolymerized and VLC) resin materials. Also to assess the mechanical properties (wear rate and transverse strength) of the Duran® Biostar Foil and compared them with that of the other splints materials (heat-cure acrylic and VLC) resins. Results:The results showed highly significant differences at P<0.01 between all studied groups except the in dimensional changes of Imprelon® and VLC, and in wear rate of heat cure acrylic and VLC resins, no significant differences obtained between their studied groups. Conclusions: Imprelon® is dimensionally stable, so it can be used directly after fabrication, also it has a good shear bond to zinc oxide eugenol impression material but it may not provide mechanical retention to other elastomeric impression materials and their adhesives since it has a low value of surface roughness (Ra).Duran® is recommended for short time use in patients with acute pain and/or dysfunction symptoms.
يأتي الاستخدام العالمي لبولي ميثيل ميثاكريلات (PMMA) كمادة أساسية لأطقم الأسنان من سهولة المعالجة والإصلاح والتوافق الحيوي والمظهر الجمالي الممتاز. ومع ذلك ، فإن أوجه القصور في مواد البوليمر ، مثل الخواص الميكانيكية والفيزيائية غير كافية. كان الغرض من هذه الدراسة هو تقييم القوة المستعرضة وقابلية البلل PMMA بعد الاختلاط مع جزيئات الزركونيا و PMMA المبلمرة [ZP] كمواد مالئة بنسبة مختلفة. المواد والأساليب: تم اقترا
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in this paper copper oxide (cuO thin films were prepared by the method of vacum thermal evaporation a pressure.
This contribution investigates the effect of the addition of the Hubbard U parameter on the electronic structural and mechanical properties of cubic (C-type) lanthanide sesquioxides (Ln2O3). Calculated Bader's charges confirm the ionic character of Lnsingle bondO bonds in the C-type Ln2O3. Estimated structural parameters (i.e., lattice constants) coincide with analogous experimental values. The calculated band gaps energies at the Ueff of 5 eV for these compounds exhibit a non-metallic character and Ueff of 6.5 eV reproduces the analogous experimental band gap of cerium sesquioxide Ce2O3. We have thoroughly investigated the effect of the O/Ce ratios and the effect of hafnium (Hf) and zirconium (Zr) dopants on the reduction energies of C
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Configured binary polymer blends of epoxy and Polyurethane was chosen varying proportions of these materials led to the production of homogeneous mixtures of Althermust Althermust and descent was poured polyurethane models required in the form of 4 mm thick plates
Interest has largely centered on the use of plant fibers to reinforce plastics, because these fibers are abundant and cheap. Carrot fibers (Curran) have been extracted from carrot, left over from carrot juice manufacture. The fibers of two sizes fine (50<µm) and coarse (100-150 µm) have been mixed with epoxy in four levels of loading (10, 20, 30, 40 wt %) respectively. Impact test, shore d hardness test and three point bending test of epoxy and carrot fiber-epoxy composites samples have been determined. The impact strength values of samples prepared with fine and coarse fibers increased as compared with pure epoxy sample. Hardness values increased, and the Young’s modulus values decreased with fiber content of both sizes.
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Burnishing improves fatigue strength, surface hardness and decrease surface roughness of metal because this process transforms tensile residual stresses into compressive residual stresses. Roller burnishing tool is used in the present work on low carbon steel (AISI 1008) specimens. In this work, different experiments were used to study the influence of feed parameter and speed parameter in burnishing process on fatigue strength, surface roughness and surface hardness of low carbon steel (AISI 1008) specimens. The first parameter used is feed values which were (0.6, 0.8, and 1) mm at constant speed (370) rpm, while the second parameter used is speed at values (540, 800 and 1200) rpm and at constant feed (1) mm. The results of the fatigue
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Autorías: Mustafa Abdulamir Hussain, Ahmed Sebeaatea Almujamay, Riyadh khaleel khammas. Localización: Revista iberoamericana de psicología del ejercicio y el deporte. Nº. 5, 2022. Artículo de Revista en Dialnet.
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In this study, plastic wastes named (PET and PVC) were used to prepare polymer matrix composite (PMC) which can be used in different applications. Composite materials were prepared by mixing unsaturated polyester resin (UP) with plastic wastes, two types of plastic waste were used in this work included polyethylene-terephthalate (PET) and Polyvinyl chloride (PVC) with various weight fractions (0, 5,10,15, 20 and 25%) added as a filler in flakes form. In this work, some of the tests that were carried out included (tensile, bending, and compressive strength) as mechanical tests, in addition to (thermal conductivity and water absorption) as physical tests. The values of tensile, compressive strength and Young's modulus of UP increased after
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