The study included adding antimony oxide to mixtures of coating metal surfaces (Enameling), after it was selected ceramic materials used in the coating metal pieces of the type of steel and cast iron in two layers. The first is called a ground coat and the second is a cover coat.
Ceramic materials layer for ground coat have been melted down in
platinum crucible at a temperature of 1200oC to prepare the glass
mixture (Frit). It was coated on metals at a temperature of 780oC for
two minutes, while the second layer was prepared glass mixture
(Frit) at a temperature of 1200oC, but was coated at a temperature of
760oC for two minutes.
Underwent tests crystalline state of powders (Frits) and enameled samples using X-ray diffraction technique and found that the process of powders and ground coat layer is random, while the cover layer included having developed a silicon oxide and titanium oxide phases. It was measured density, coating thickness and Knoop hardness for each layer. As well as practical tests conducted dipping enameled samples in diluted and concentrated sulfuric acid, as well as diluted and concentrated hydrochloric acid for three days at a temperature of 100oC. The samples showed good resistance against these acids. The addition of antimony oxide reduced the presence of bubbles in the coated cast iron and enhancement physical and mechanical properties.
Background: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left u
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The purpose of this research is to improve the organizational performance of the Oil Projects Company by adopting an approach to strategic change، and finding appropriate solutions to the problems facing the company. The researcher adopted in designing his research by conducting a survey of previous literature that dealt with approaches to strategic change، as the results of the survey showed that most researchers agree on the approach of renewal and modernization، Which formed a starting point for the researcher to identify the extent of the company's management interest in renewal and modernization to improve its level of performance، and the quality of the procedures followed on the ground that is related to
... Show MoreThe Iraqi culture faced a set of challenges that can be diagnosed with the most prominent features as follows:
- The dominance of authoritarian political systems which entails authoritarian regimes with the absence of contemporary political concepts of human rights.
- The prevalence of non- informed cultural systems which have the shortage of capabilities that enable them to activate cultural elements in positive references, historical, or seclusion on itself and not be able to interact with the current active cultures.
- Stagnant economic conditions have not had a decent life for individuals, or a certain level of well-being, as well as poor services and others.
- Social life controlled by the prevai
This study aims to find the effect of water-cement ratio on the compressive strength of concrete by using ultrasonic pulse velocity test (UPVT). Over 230 standard cube specimens were used in this study, with dimensions of 150mm, and concrete cubes were cured in water at 20 °C. Also, the specimens used in the study were made of concrete with varied water-cement ratio contents from 0.48 to 0.59. The specimens were taken from Diyarbakir-Turkey concrete centers and tested at the structure and material science lab, civil engineering, faculty of engineering from Dicle University. The UPV measurement and compressive strength tests were carried out at the concrete age of 28 days. Their UPV and compressive strength ranged
... 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 MoreMaterials and Methods Bacterial strains P. aeruginosa was obtained from postgraduate students Laboratories of Biology Department/College of Science/University of Baghdad. That previously isolated from patient suffering from Cystic Fibrosis. API 20 NE system was employed for the identification of P. aeruginosa. A total of 122 urine specimens were collected in the period between of mid of July until to the mid of September of 2010 from AL-Kadhmiya Teaching Hospital in Baghdad City. Specimens were collected from out-patients in sterile screw cupped containers. Regarding inpatients, catheter was withdrawn and cut
Non-thermal plasmas have become popular as plasma technology has advanced in various fields, including waste management, aerospace technology, and medicinal applications. They can be used to replace combustion fuels in stationary hall motors and need little effort to keep running for longer periods of time. To improve overall system performance, non-reactive gases such as )Xe, Ar, and Kr) are utilized in pure or mixed form to generate plasma. Since DC glow discharge is a fundamental topic of importance, these gases have been researched. The paper concentrates on 2-D modeling and simulation. DC glow-discharge tubes are utilized with argon gas to create plasma and learn about its properties. The magnitude of the electron density, increases wi
... Show MoreObjective: The current study aimed identifying the impact of rehabilitative exercises combined with ultrasonic waves on reducing pain in people with carpal tunnel compression and determining how these activities affect range of motion of the upper limb for those suffering from carpal tunnel compression. Research methodology: With pre- and post-tests, the researchers employed the experimental method in the form of two equal groups, the experimental and the control. The scientific community and sample are among the priorities that fall on the researcher, so The scientific community is determined by those suffering from carpal tunnel compression, numbering (14) patients. (12) Patients were approved and two were excluded from the resear
... Show MoreObjective: The current study aimed identifying the impact of rehabilitative exercises combined with ultrasonic waves on reducing pain in people with carpal tunnel compression and determining how these activities affect range of motion of the upper limb for those suffering from carpal tunnel compression. Research methodology: With pre- and post-tests, the researchers employed the experimental method in the form of two equal groups, the experimental and the control. The scientific community and sample are among the priorities that fall on the researcher, so The scientific community is determined by those suffering from carpal tunnel compression, numbering (14) patients. (12) Patients were approved and two were excluded from the resear
... Show Moreunacceptable social behaviors, particularly withdrawal behavior that appears in children with autism represent a major problem hindering the process of communication with those around them and therefore the process of mergence with them be difficult.
The withdrawal causes a real affect deficit for children with autism limits the possibility of development of their intellectual and mental growth due to their solitude and the weakness of their focus in the acquisition of pedagogical skills and lack the necessary social skills to maintain the relations of friendship and enjoyment of them.
withdrawal children fail to participate
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