Background: Dental stone casts come into contact with impression materials and becomes susceptible to cross contamination from saliva and blood. This study was done to evaluate the physical and mechanical properties of dental stone type IV after treatments with various disinfecting agents and regimes (methods). Materials and Methods: Type IV dental stone and different types of disinfecting agents were used and divided into seven groups: G1: dental stone without disinfection (control group), G2: dental stone mixed with silver nitrate powder 0.5% , G3: dental stone mixed with silver nitrate powder 1%, G4: dental stone mixed with copper sulfate powder 0.5%, G5: dental stone mixed with copper sulfate powder 1% ,G6: dental stone immersed in propanol 70% and G7: dental stone immersed in ethanol 70%.Setting time, linear setting expansion, surface detail reproduction, compressive strength of type IV dental stone as well as compatibility with auto mixing addition silicone impression material were evaluated. The statistical analysis were conducted by ANOVA test followed by LSD test (p<0.05), also chi square test was used. Results: The compressive strength, linear setting expansion, surface detail reproduction and compatibility of stone specimens was affected to a higher extent by mixing with silver nitrate powder 1%, copper sulfate powder 1% while treating the stone specimens with the disinfecting powders at low concentrations as well as immersion of stone specimens in either ethanol or propanol for 15 minutes produce less effect on the previous tested properties. Conclusion: Silver nitrate 0.5%, copper sulfate 0.5% powders as well as 15 minutes immersion in 70% ethanol or 70% propanol did not promote adverse alterations in most of evaluated properties of type IV dental stone.
The study's objective is to produce Nano Graphene Oxide (GO) before using it for batch adsorption to remove heavy metals (Cadmium Cd+2, Nickel Ni+2, and Vanadium V+5) ions from industrial wastewater. The temperature effect (20-50) °C and initial concentration effect (100-800) mg L-1 on the adsorption process were studied. A simulation aqueous solution of the ions was used to identify the adsorption isotherms, and after the experimental data was collected, the sorption process was studied kinetically and thermodynamically. The Langmuir, Freundlich, and Temkin isotherm models were used to fit the data. The results showed that Cd, Ni, and V ions on the GO adsorbing surface matched the Langmuir model with correlation coefficients (R2)
... Show MoreIn this work, polyvinylpyrrolidone (PVP)/ Multi-walled carbon nanotubes (MWCNTs) nanocomposites were prepared with two concentrations of MWCNTs by casting method. Morphological, structural characteristics and electrical properties were investigated. The state of MWCNTs dispersion in a PVP matrix was indicated by Field Effect-Scanning Electron Microscopy (FESEM) which showed a uniform dispersion of MWCNTs within the PVP matrix. X-ray Diffraction (XRD) indicate strong bonding of carbonyl groups of PVP composite chains with MWCNTs. Fourier transfer infrared (FTIR) studies shows characteristics of various stretching and bending vibration bands, as well as shifts in some band locations and intensity changes in others. Hall effect was studied
... Show MorePoly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinyl] (MEH-PPV) thin films were created in this study using both spin coating and drop casting processes. MEH-PPV thin films generated by Ferric Chloride (FeCl3) doping (0.03, 0.06, 0.09, and 0.12 wt%) were studied for some physical features using Fourier-Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FE-SEM), and Energy Dispersive X-ray Spectroscopy (EDX). An FTIR test showed that there was no chemical reaction that occurred between Ferric Chloride (FeCl3) and MEH-PPV, but rather a physical one, that is, an organic material composite occurred. As for FE-SEM, the pure sample MEH-PPV formed uniformly, but when FeCl3 was added by weight, we have differ
... Show MorePostmodern arguments, formed a critic case of what modernity brought in several levels. Postmodern practice was considered as a proactive case having amorphous concepts and features to what entiled as an intellectual trends postmodern philosophically and intellectually. But, what postmodernism architecture broughts in it essence, was not isolation from the intellectual context and entrepreneurship case, and it was not disconnecting from the intellectual and philosophical era of that period. Lliteratures and philosophical argument precede what (Robert Venturi) and (Charles A Jencks) had brought, albeit it was closer to critics and correction the path of modernity from crystallizing a direction that exceeds modrinity to wh
... Show MoreIn this research, a novel thin film Si-GO10 and nanopowders Si-GO30 of silica-graphene oxide (GO) composite were prepared via the sol–gel method and deposited on glass substrates using spray pyrolysis. X-ray diffraction (XRD) results showed a relatively strong peak in the graphite layer that corresponds to the (002) plane. Transmission electron microscope (TEM) images showed that SiO2 nanoparticles were randomly distributed on the surface of GO plates, and the particle size in these nanopowders was below 50 nm. Field emission scanning electron microscopy (FESEM) analysis demonstrated that silica nanoparticles on the surface of GO plates exhibited almost spherical and rod-like nanoparticle shape, which in turn confirmed the formation of Si
... Show MoreThe present work intends to study of dc glow discharge were generated between pin (cathode) and a plate (anode) in Ar gas is performed using COMSOL were used to study electric field distribution along the axis of the discharge and also the distribution of electron density and electron temperature at constant pressure (P=.0.0mbar) and inter electrode distance (d=4 cm) at different applied voltage for both pin cathode system and plate anode and comparison with experimental results.
This study aimed to know the attitudes and practice of pharmacists regarding the management of minor ailments in Iraqi community pharmacies. A cross-sectional study for 320 community pharmacists was conducted during February 2020 using a newly developed and validated questionnaire. Only 4.4% of pharmacists prefer not to deal with minor ailment cases. Minority (15.6%) of participated pharmacists refer more than half of minor ailment cases they face to the physician. Regarding the assessment of minor ailments using WWHAM technique, what are the symptoms are the most commonly asked questions by pharmacists. Only 49.1% mentioned that they ask all WWHAM questions. On the other hand, most pharmacists (90%) educate their patients about the dosi
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