Background: The PMMA polymer denture base materials are low mechanical properties, adaptation of the denture base to underlying tissue is important for retention and stability of denture. The aim of the study was toevaluate the effect of mixtureZrO2-Al2O3 nanoparticles on impact strength, transverse strength, hardness, roughness, denture base adaptation of heat cured acrylic resin denture base material. Materials and methods: One hundred (100) specimens were prepared, the specimens were divided into five groups (20 specimens to each) according to the test type, each group was subdivided in to two subgroups (control and experimental) each subgroup consist of 10 specimens, the experimental group included mixture of 2% (ZrO2-Al2O3ratio2:1) by weight. Theimpact strength was measured by Charpy's impact testing machine, the transverse strength was measured by Instron testing machine while the hardness was measured byshore D durometer and roughness was measured by Profilometer. Denture base adaptation was measured by digital microscope and evaluated by computerized tomography (CT). Results: Highly significant increaseofimpact and transverse strength, non-significant increase ofhardness, significant increase ofroughness andreduction of denture base adaptation (measured at 3 point A, B and C) occurred in experimental groupwhen compared to control group. CT evaluation, gap between the denture base and master cast (control and experimental groups) increased from the anterior to posterior side of palate and from the alveolar ridge to the mid palatal line. Conclusion: The polymer nanocomposites had mechanical properties higher than neat PMMA at same time less denture base adaptation.
The aim of the work is synthesis and characterization of bidentate ligand [dipotassium sodium7-((E)-2-(2-((Z)-1-carboxylatoethylideneamino)thiazol-4-yl)-2 (carboxylatemethoxyimino) acet amido)-8-oxo-3-vinyl-5- thia-1-azabicyclo[4.2.0] oct-2- ene-2- carboxylate] [Nak2L], from the reaction of cefixime with sodium pyruvet to produce the ligand [Nak2L], the reaction was carried out in methanol as a solvent under reflux. The prepared ligand [Nak2L] which was characterized by FT-IR, UV-Vis spectroscopy, 1H, 13C-NMR spectra, Mass spectra, (C.H.N) and melting point. The mixed ligand complexes were prepared from ligand [Nak2L] was used as a primary ligand while 8-hydroxy quinoline [Q] was used as a secondary ligand with metal ion M(Π).Where
... Show MoreThe aim of the work is synthesis and characterization of bidentate ligand [dipotassium sodium7-((E)-2-(2-((Z)-1-carboxylatoethylideneamino)thiazol-4-yl)-2 (carboxylatemethoxyimino) acet amido)-8-oxo-3-vinyl-5- thia-1-azabicyclo[4.2.0] oct-2- ene-2- carboxylate] [Nak2L], from the reaction of cefixime with sodium pyruvet to produce the ligand [Nak2L], the reaction was carried out in methanol as a solvent under reflux. The prepared ligand [Nak2L] which was characterized by FT-IR, UV-Vis spectroscopy, 1H, 13C-NMR spectra, Mass spectra, (C.H.N) and melting point. The mixed ligand complexes were prepared from ligand [Nak2L] was used as a primary ligand while 8-hydroxy quinoline [Q] was used as a secondary ligand with metal ion M(?).Where M(?) =
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In this study, composite materials were prepared using unsaturated polyester resin as binder with two types of fillers (sawdust and chopped reeds). The molding method is used to prepare sheets of UPE / sawdust composite and UPE / chopped reeds composite. The mechanical properties were studied including flexural strength and Young's modulus for the samples at normal conditions (N.C). The Commercial wood, UPE and its composite samples were immersed in water for about 30 days to find the weight gain (Mt%) of water for the samples, also to find the effect of water on their flexural strength and Young's modulus. The results showed that the samples of UPE / chopped reeds composite gained highest values of flexural strength (24.
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We consider the outflow of water from the peak of a triangular ridge into a channel of finite depth. Solutions are computed for different flow rates and bottom angles. A numerical method is used to compute the flow from the source for small values of flow rate and it is found that there is a maximum flow rate beyond which steady solutions do not seem to exist. Limiting flows are computed for each geometrical configuration. One application of this work is as a model of saline water being returned to the ocean after desalination. References Craya, A. ''Theoretical research on the flow of nonhomogeneous fluids''. La Houille Blanche, (1):22–55, 1949. doi:10.1051/lhb/1949017 Dun, C. R. and Hocking, G. C. ''Withdrawal of fluid through
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Aim: To evaluate the wettability and microhardness of Zirconium (ZrO2) dental material when coated with different concentrations of Faujasite. Materials and methods: 30 circular disks produced from ZrO2, then each group is classified into 10 control groups, 10 coated groups with 3% Faujasite, and 10 coated groups with 7% faujasite by electro-spun tool to study variable properties in hardness and water contact angle of implant materials. Results: This study stated the high hardness in 7% of faujasite concentration for ZrO2, in addition, the contact angle decreased gradually until reach 0 ᵒ in 7% concentration of faujasite with ZrO2 Conclusion: Water contact angle (WCA) declined till disappeared in (7% wt.) of faujasite coated with the Z
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This search aim to measure Hardness for Epoxy resin and for unsaturated Polyester resin as base materials for composite Hybrid and the materials used is Hybrid fiber Carbon-Kevlar. The Hand Lay-up method was used to manufacture plates of Epoxy resin (EP) and unsaturated Polyester EP,UPE backed by Hybrid fiber (Carbon-Kevlar) and with small volume fraction 5,10 and 15 for every there are Layer of fibers (1,2 and 3). The hardness test was count for material EP, UPE resin and there composites and that we notice that the Hardness (HB) decreased with increase of temperatures.
The ligand [Potassium (E)-(4-(((2-((1-(3-aminophenyl) ethylidene) amino)-4-oxo-1,4dihydropteridin-6-yl) methyl) amino)benzoyl)-L-glutamate] was prepared from the condensation reaction of folic acid with (3-aminoacetophenone) through Schiff reaction to give a new Schiff base ligand [H2L]. The ligand [H2L] was characterized by elemental analysis CHN, atomic absorption (A.A), (FT-I.R.), (U.V.-Vis), TLC, E.S. mass (for spectroscopes), molar conductance, and melting point. The new Schiff base ligand [H2L], reacts with Mn(II), Co(II), Ni(II), Cu(II), Cr(III) and Cd(II) metal ions and (2-aminophenol), (metal : derivative ligand : 2-aminophenol) to give a series of new mixed complexes in the general formula:- K3[M2(HL)(HA)2], (
... Show MoreThe ligand [Potassium (E)-(4-(((2-((1-(3-aminophenyl) ethylidene) amino)-4-oxo-1, 4-dihydropteridin-6-yl) methyl) amino) benzoyl)-L-glutamate] was prepared from the condensation reaction of folic acid with (3-aminoacetophenone) through Schiff reaction to give a new Schiff base ligand [H2L]. The ligand [H2L] was characterized by elemental analysis CHN, atomic absorption (AA),(FT-IR),(UV-Vis), TLC, ES mass (for spectroscopes), molar conductance, and melting point. The new Schiff base ligand [H2L], reacts with Mn (II), Co (II), Ni (II), Cu (II), Cr (III) and Cd (II) metal ions and (2-aminophenol),(metal: derivative ligand: 2-aminophenol) to give a series of new mixed complexes in the general formula:-K3 [M2 (HL)(HA) 2],(where M= Mn (II) and Cd
... Show MoreIn this paper a thin films of selenium was prepare on substrates of n-Si by evaporation in a vacuum technique with thickness about 0.5μm. And then an annealing process was done on samples at two temperature (100 and 200) C ° in a vacuum furnace (10-3 torr).
Some structural, optical and mechanical properties of prepared thin films were measured. Results showed that the prepared film was the crystallization, optical transmittance and micro hardness of the prepared thin films increased significantly after annealing.