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Effects of time delay and tension system application after final flask closure on the vertical displacement of acrylic and porcelain teeth in maxillary complete dentures
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Background: The displacement of artificial teeth during complete denture construction presents major processing errors in the occlusal vertical dimension which were verified at the previous trial denture stage. The aim of this study was to assess the effect of delay in processing after final flask closure and tension application on the vertical acrylic and porcelain teeth displacement of complete dentures constructed from heat cured acrylic and the results were compared with the conventional processing method. Materials and methods: forty samples of identical maxillary complete dentures were constructed from heat polymerized acrylic resin. These samples were subdivided into the following experimental subgroups in which each subgroup contains 5 samples for both acrylic and porcelain teeth and as follows: 1. Conventional flasking technique and immediate processing. 2. Conventional flasking technique and 6 hours delay in processing. 3. flasking technique with tension system and immediate processing. 4. flasking technique with tension system and 6 hours delay in processing. Reference metal pins were attached to the middle of the buccal surface of the upper right canine and center of the buccal groove of the left first molar. And according to these reference points on the teeth another metallic Reference pins were fixed on the denture vestibules and at a distance of 7.5mm by straight lines and 6.5mm where placed between the metal pins and the vestibules in order to standardize the measurement. The distance between the right and left metal pins on the canine and molars and the corresponding metal pins on the buccal vestibules were measured during the wax up stage and after processing by using an optical travelling microscope with an accuracy of 0.0005 mm. Means in (mm) were analyzed statistically by analysis of variance and the comparative T-test and least significance test (LSD). Results: Significant reduction in vertical displacement of the teeth occurred in groups when 6 hours delay in processing were applied, but a significant improvement was also observed in groups with tension system application when compared with control group. On the other hand, there were a high significant reduction in the vertical displacement in groups with tension system and 6 hours delay in processing combination. While for the type of artificial teeth data showed significant difference in the amount of vertical displacement of the teeth in groups with acrylic teeth when compared with porcelain teeth. Conclusions: The findings of this study showed that 6 hours delay in processing and tension system application were effective in reducing the vertical displacement of the artificial teeth during flasking. The maximum reduction in the displacement was observed in dentures constructed from acrylic teeth. On the other hand, significant decrease in vertical displacement of the teeth was detected in dentures constructed from porcelain teeth.

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Computer-Aided-Design of low aberration electrostatic Immersion lens
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A computerized investigation has been carried out to design an immersion lens
with low aberration operating under zero magnification condition using inverse problem.
The aberration is highly dependent on the shape of electrodes, for a preassigned electron
beam trajectory the paraxial-ray-equation is solved to determine the electrostatic potential
and field distribution.
From the knowledge of the potential and its first and second derivative the
electron optical properties were computed, the electrode geometry was determined from
the solution of Laplace equation.

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Publication Date
Fri Aug 02 2024
Journal Name
Journal Of Electrochemical Energy Conversion And Storage
Electrochemical Performance of Co1-xMnxFe2O4 Decorated Nanofiber Polyaniline Composites
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The current work is concerned with preparing cobalt manganese ferrite (Co1-xMnxFe2O4) with different concentrations of cobalt and manganese (x=0.2, 0.4, and 0.6) and decorating it with polyaniline (PAni) for use in supercapacitive applications. The results of the X-ray diffraction (XRD) manifested a broad peak of PAni and a cubic structure of cobalt manganese ferrite having crystal size between 60 nm and 138 nm, which decreases with increasing concentration of Mn. The field emission scanning electron microscopy (FESEM) images evidenced that the PAni has nanofiber (NF) structures, according to the method of preparation, where the hydrothermal method was used. The magnetic properties of the prepared ferrite, as well as the prepared PAni/Co1-x

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Publication Date
Thu Jun 10 2010
Journal Name
Iraqi Journal Of Laser
Generation of Weak Coherent Pulses for Quantum Cryptography Systems
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This work is a trial to ensure the absolute security in any quantum cryptography (QC) protocol via building an effective hardware for satisfying the single-photon must requirement by controlling the value of mean photon number. This was approximately achieved by building a driving circuit that provide very short pulses (≈ 10 ns) for laser diode -LD- with output power of (0.7-0.99mW) using the available electronic components in local markets. These short pulses enable getting faint laser pulses that were further attenuated to reach mean photon number equal to 0.08 or less.

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Publication Date
Tue Sep 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Viscosity Index Improvement of Lubricating Oil Fraction (SAE – 30)
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An investigation was conducted for the improvement of viscosity index of a lubricating oil fraction (SAE – 30) obtained from vacuum distillation unit of lube oil plant of Daura Refinery, using solvent extraction process. In this study two type of extraction solvents were used to extract the undesirable materials which reduce the viscosity index of raw lubricating oil fraction, the first solvent was furfural which is un use today in the Iraqi refineries and the second was NMP (N-methyl, 2, pyrrolidone) which is used for the first time in this work to extract the lubricating oil fraction produced from Iraqi crude oils. The studied effecting variables of extraction are extraction temperature range from 70 to 110 oC for furfural and NMP ex

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Publication Date
Sun Jun 30 2002
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Removal of Sulfur Dioxide from Sulfuric Acid Plant Emissions
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Publication Date
Thu Dec 01 2016
Journal Name
Journal Of Engineering
Behavior of Reinforced Concrete Continuous Beams under Pure Torsion
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Practically, torsion is normally combined with flexure and shear actions. Even though, the behavior of reinforced concrete continuous beams under pure torsion is investigated in this study. It was performed on four RC continuous beams under pure torsion. In order to produce torsional moment on the external supports, an eccentric load was applied at various distances from the longitudinal axis of the RC beams until failure.

Variables considered in this study are absolute vertical displacement of the external supports, torsional moment’s capacity, angle of twist and first cracks occurrences. According to experimental results; when load eccentricity increased from 30cm to 60cm, the absolute vertical displacement i

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Publication Date
Sun Jun 06 2010
Journal Name
Baghdad Science Journal
Anovel Immunological Technique for Identification of Human Seminal Fluid
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An immunological technique was investigated for the detection of human semen in forensic analysis.This technique included a preparation of anti-human seminal plasma antibodies, by immunizing rabbits with treated human semen. The human semen was treated with an acid to prevent cross reactivity with other human body fluids. The antibody produced was tested against different animal,s seminal fluid samples (dog, goat ,sheep, cow) and human body fluids( saliva, blood , vaginal fluid, ear wax and human semen). It was found that using this developed technique was only selectively responsed with human semen . The prepered kit was evaluated and tested in Forensic laboratory- Ministry of Health. Finally, results were obtained in a c

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Publication Date
Tue Jun 21 2022
Journal Name
Journal Of Planner And Development
Enviromental impact assessment of cement industry using Leopold Matrix
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The assessment of the environmental impact of the cement industry using the Leopold Matrix is ​​to determine the negative and positive impacts on the environment resulting from this industry, and what are the long-term and short-term effects, direct and indirect, and the amount of these effects and potential risks, and that this evaluation process is done through a number of methods, including Matrix method, including (Leopold).

 

The importance of the research because the cement occupies is of great importance in the world, especially in our country, Iraq, in the sector of construction and modernity, and the toxic emissions and solid waste produced by the production of this material. <

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Publication Date
Mon Jun 04 2018
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Dissolution Enhancement of Raltegravir by Hot Melt Extrusion Technique
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The objective of the study to develop an amorphous solid dispersion for poorly soluble raltegravir by hot melt extrusion (HME) technique. A novel solubility improving agent plasdone  s630 was utilized. The HME raltegravir was formulated into tablet by direct compression method. The prepared tablets were assessed for all pre and post-compression parameters. The drug- excipients interaction was examined by FTIR and DSC. All formulas displayed complying with pharmacopoeial measures. The study reveals that formula prepared by utilizing drug and plasdone S630 at 1:1.5 proportion and span 20 at concentration about 30mg (trail-6) has given highest dissolution rate than contrasted with various formulas of raltegravir.

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Publication Date
Fri Jan 01 2016
Journal Name
Japanese Geotechnical Society Special Publication
Treatment of Iraqi collapsible soil using encased stone columns
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Stone columns are widely used globally due to theirversatility and relative wide applicability to treat different soil and foundation situations but much of the research undertaken to date has focused on their use in soft soils. In countries like Iraq the use of stone columns is still limited from a practical point of view, chiefly as many other soil conditions are commonly encountered. These include collapsible soils: soils that are prone to relatively rapid volume compressions (through collapse of metastable fabrics) that occur due to the action of load and/or increases in water content. Recent work has opened up the possibility to use stone columns in these soils by the use of encasement, thereby overcoming the impact of loss of lateral

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