Objective(s): In the present study, glycerin is used as a substitute for tin-foil and cold mold seal (Alginate mould seal)
in the process of curing heat and cold-cure acrylic resin denture base against stone and plaster.
Methodology: 60 specimens were prepared from heat-cure acrylic resin and cold-cure acrylic resin denture base. The
study includes 12 groups of specimens depending on the type of processing, investment material and type of
separating medium that are used in curing process. Each group of them contains 5 specimens for each test.
Some of physical properties of the processed acrylic denture base that (water sorption and solubility) have been
compared with those processed using tin-foil and tin-foil substitute.
Results: The results have shown that tin-foil is still the best separating medium that is used due to the best properties
obtained when using tin-foil as a separating medium, while no significant differences have been observed between
glycerin and cold mold seal specimens in respect to water sorption and solubility of the testing groups.
Recommendations: that glycerin can be considered as a satisfactory separating medium for both heat and cold-cured
acrylic denture base resins, especially because it is easy to get, easy to use and cheap.
Background: The new concepts and technologies continue to change the dynamics of endodontic practices in the world. Rapid and significant changes in techniques, instrument design, and the type of metals used to manufacture endodontic instruments which have been made during the last few years in an attempt to overcome canal preparation errors. The purpose of this study is to measure and compare canal transportation and centering ability of Self Adjusting File with two rotary nickel-titanium (Ni-Ti) systems, ProTaper and BioRaCe at different levels. Material and Methods: Forty five distal roots of mandibular first molars with moderate curvature were selected using Schneider method. Roots were divided randomly into 3 groups of 15 each and were
... Show MoreWrestling Judo, one of the sports that have seen greatdevelopment in recent years in the world, requiring preparationphysically special, which is to be determined physical aptitude of thebad functional efficiency of the heart and lungs, Efficient physicalclosely linked to the ability of the player performance, as the physicalaptitude to play an important role the possibility of control over theaspects and physical skills during training and competition.The study aims to determine the effect of training on anaerobicendurance according to the average (30-60 sec) in the development ofphysical aptitude for judo players. Used a much more extremeexperimental method on a sample was Blaabat national teamwrestling judo and numbers of 16 for the play
... Show MoreBiological study was conducted in the botanical garden of the College of Education / Ibn Al-Haitham during the growing season 2006-2007 to determine the impact different date planting and variety in some morphological characteristics of the wheat plant Triticum astivum L. Two varieties of Triticum aestivum L.: IPA99 and Abu-Ghraib , were cultivated in 4th , 25th of November and 9th of December . The experiment was designed according to RCD in two replicates. The results showed that cultivation of 4th November, gave rise to plants of high 74.66 cm, with the highest number of tillers which was 4.01 and the highest length of spike was 12.03
... Show MoreFree cement refractory concrete is a type of refractory concrete with replacing alumina cement by bonding materials such as white kaolin, red kaolin and fumed silica. The free cement refractory concrete used in many applications like Petrochemicals, iron furnaces and cement production industries. The research clarifies the effect of steel fibers with two types crimped steel fibers and hooked steel
fibers with percentages 0.5%, 1% and 1.5% by volume from weight of bauxite aggregates. The additions of steel fibers with two types gave good properties in high temperatures where the specimens keep the dimension without failure and the properties made the best. the percentage of increasing for thermal conductivity was 44% for 1.5% crimped
EP/ metal composites were prepared as adhesives between two steel rods. Epoxy resin (EP) was used as a matrix with metal as fillers (Al, Cu, Fe,).
The preparation method for tensile adhesion tests includes two steel rods with adhesive composites between the rods to measure adhesion strength Sad and adhesion toughness Gad.
Results of tensile adhesion tests show that EP/ metals composite have maximum strength Sad for certain weight percentage of metals 2.95 and 9MPa at 10% for EP/Al and EP/Cu composite and 8.2MPa at 40% for EP/Fe composites
Sheets of Epoxy (EP) resin with addition of TiO2 of grain size (1.5μm, and 50nm) and weight percentage (1%, 3%, and 5%) were prepared. Discs of 20mm diameter and 3mm thickness were cut for dielectric measurements. Dielectric properties (dielectric constant, dispassion factor and electrical conductivity) over the frequency range 102 -106 Hz were measured.
Comparison was made between the effect of micro and nano particles of TiO2 on the dielectric properties of EP composites with different weight percentage. Epoxy composites with micro sized particles of TiO2 were observed to have the better values of dielectric properties.
This study is concerned with the effect of Deep Cryogenic Treatment (DCT) at liquid nitrogen temperature (-196 o C) on the mechanical properties and performance of low carbon steel (A858). The tests specimens were divided in to two groups, the first group was subjected to the conventional heat treatment of normalizing, and the second group was also normalized then subjected to (DCT). The results have shown that after (DCT), the Hardness, Tensile properties and the impact energy absorbed were all slightly increased. However the fatigue test showed some positive improvement in fatigue limit by 20(N/mm2 ), and the volume wear rates at different loads were significantly decreased after (DCT). The changes in microstructure due to (DCT) were c
... Show MoreCuInSe2(CIS) thin films have been prepared by use vacuum thermal evaporation technique, of thickness750 nm with rate of deposition 1.8±0.1 nm/sec on glass substrate at room temperature and pressure (10-5) mbar. Heat treatment has been carried out in the range (400-600) K for all samples. The optical properties of the CIS thin films are been studied such as (absorption coefficient, refractive index, extinction coefficient, real and imaginary dielectric constant) by determined using Measurement absorption and transmission spectra. Results showed that through the optical constants we can make to control it are wide applications as an optoelectronic devices and photovoltaic applications.
Judicial jurisprudence is one of the important legal solutions to address the shortcomings of legislation. Throughout its long history, human societies have known many cases in which the judge finds himself facing a legislative vacuum in addition to civil legal texts that are difficult for the judge to implement due to ambiguity or contradiction, which requires diligence. To rule on resolving disputes before him in order not to deny justice, but the judge in his jurisprudence was not absolute, but rather bound by certain controls represented by observing the wisdom of legislation on the one hand and taking into account the nature of the texts on the other side, and from here this research came to shed light on the jurisprudence and its cont
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