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Crystallization firing effect on the marginal discrepancy of the IPS. emax CAD crowns using two different CAD/CAM systems
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Background: Marginal adaptation is critical for long – term success of crown and bridge restoration. Computer aided design / computer aided manufacture (CAD/ CAM) system is gaining more importance in the fabrication of dental restoration. Objective: The aim of this study is to evaluate the effect of crystallization firing on the vertical marginal gap of IPS. emax CAD crowns which fabricated with two different CAD/CAM systems .Materials and Methods: Twenty IPS e.max CAD crowns were fabricated. We had two major groups (A, B) (10 crowns for each group) according to the CAD/CAM system being used: Group A: fabricated with Imes - Icore CAD/CAM system; Group B: fabricated with In Lab Sirona CAD/CAM system. Each group was subdivided into two subgroups pre-crystallized (Group A1, B1) and crystallized crowns (Group A2, B2). At four points on each aspect of the crown, marginal gaps were assessed on the master metal die by using digital microscope at a magnification of (110X) and image- J program. The measurement was done twice for each crown; before and after crystallization process.Results: The lowest mean of marginal gap before and after crystallization was (29.387±2.774μm) and (70.108±5.569μm) respectively for Group A (Imes - Icore system) and the highest mean value before and after crystallization was (51.728 ±3.774μm) and (84.071 ±4.567μm) respectively for Group B (Sirona system). Paired sample t-test result showed a statistically highly significant difference in marginal gap between all groups.Conclusions: The crystallization process increases the vertical marginal gap. Imes - Icore system showed the lower marginal gap than Sirona system. The two systems have an acceptable marginal gap

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Publication Date
Thu Feb 07 2019
Journal Name
Iraqi Journal Of Laser
Study the Effect of PH Variation on the Particle Size of Sio2 Thin Films
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In this paper, SiO2 nanoparticles thin films were synthesised at different PH values of solution by sol gel method at fixed temperature (25oC) and molar ratio (R =H2O/precursor) of (Tetra Ethyl Ortho Silicate) TEOS as precursor at (R=1). The structure and optical properties of the thin films have been investigated. All thin films were tested by using X-RAY diffraction. All X-RAY spectrum can be indexed as monoclinic structure with strong crystalline (110) plane. The morphological properties of the prepared films were studied by SEM. The results indicate that all films are in nano scale and the particle size around (19-62) nm .The size of silica particles increases with increasing PH value of solution where both the rate of hydrolysis and

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Publication Date
Fri Mar 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
The Effect of Asphaltenes Removal on the Kinetics of Iraqi Reduced Crude Oil Hydrotreating
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Publication Date
Sun Feb 03 2019
Journal Name
Iraqi Journal Of Physics
Studying the effect of silica (SiO2) addition on the adhesive properties of polyvinyl alcohol
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The work concerned with studying the effect of (SiO2) addition as a
filler on the adhesive properties of (PVA). Samples were prepared as
sheets by using casting method. The mechanical properties showed
that increase in tensile strength from (34MPa) to (68MPa) when
(SiO2) added to (PVA). The adhesive strength showed that joint
properties depend upon specific adhesive characteristic of material
(PVA) and (SiO2\PVA)composites at different concentrations (1.5%,
2.5%, 3.5%, 4.5wt%), the cohesive strength of the adhesive material,
the joint design, and adherent type (Sponge Rubber(SR), Natural
leather (NL), Vulcanized Rubber(VR), and Cartoon). The results
proved the tensile strength increased with (SiO2) ratio, so

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Publication Date
Sun Feb 17 2019
Journal Name
Iraqi Journal Of Physics
A study of the solvent effect on the low temperature spectra of benzoanthracene molecules
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been taken at room temperature down to liquid nitrogen temperature (77K). Polar and nonpolar solvents have been used to study the solvent effect on the absorption and fluorescence spectra of solute molecules. Some of the spectroscopic parameters have been determined as functions of solvent polarity and temperature. The results indicate that the band width FWHM increases with increasing the solvent polarity and temperature, while the peak emission cross section decreases with increasing of solvent polarity and decreases with increasing the temperatures. Clear vibrational structure spectra of benzoanthracene molecules have been observed in Nonane and Hexane solvents at 77K.

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Publication Date
Thu Oct 01 2009
Journal Name
Iraqi Journal Of Physics
The effect of Titanium dioxide on the tensile properties of Polycarbonate and Polystyrene Polymers
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This research study the effect of Titanium dioxide on the tensile properties of
Polystyrene (PS) and Polycarbonate (PC) polymers. The stress – strain curve for pure PS
and pure PC, shows that Young modulus for PS is higher than Young modulus for PC,
because PS have higher ultimate strength than PC.
The addition of TiO2 to PS and PC will reduce the Young modulus and ultimate stress,
because the TiO2 particles will reduces or freeze the orientation of these molecular chain
and reduced the toughness of PC, while when the TiO2 were added to PS, the value of
toughness will be stabilized because TiO2 particles make these chains interlocked and the
mobility of the chains will be restrict.

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Publication Date
Tue Aug 30 2022
Journal Name
Research Journal Of Pharmacy And Technology
Study the effect of biosynthesized gold nanoparticles on the enzymatic activity of alpha-Amylase
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In this paper, investigates the biosynthesis of gold nanoparticles (AuNPs) by biochemical method using Myrtus communis leaves extract as reducing agent and Chloroauric acid (HAuCl4) as precursors. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and FTIR were used in addition to UV-visible spectroscopy (UV) in order to characterize the AuNPs. The biosynthesized AuNPs exhibited inhibitory effects on alpha amylase and alkaline phosphatase in sera of patient with type 2 Diabetes Miletus and the sera of healthy control subjects; the inhibition percentage with alpha amylase was 72 % and 45 % for patient and control group respectively. Oral consent obtained from the most of patients and healthy subjects before them being under

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Publication Date
Sat Aug 01 2020
Journal Name
Journal Of Engineering
The Effect of Staggered porous fins on the performance of Photovoltaic panel in Baghdad
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The performance of photovoltaic (PV) panel having staggered metal foam fins was examined experimentally in Baghdad, Iraq. Three staggered metal foam fin configurations attached to the backside of the PV panel were studied. The measured parameters were front and back surfaces temperature, open voltage and current circuits, maximum power, and PV efficiency. It was noted that the maximum electrical efficiency enhancement was 4.7% for staggered metal foam fins (case III) than the reference PV panel. The operating temperature of the cell was increased when the value of solar intensity was high. Thereby, the electrical efficiency was decreased. It was found that the metal foam fins decreased the PV temperature by 2-3 o

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Publication Date
Wed Feb 08 2023
Journal Name
Iraqi Journal Of Science
The Effect of Solar and Lunar Attraction and SRP on the HEO of Satellite
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The perturbation of a satellite high orbit due to the presence of other
gravitational bodies (such as the Sun and the Moon) and SRP from the conservative
perturbing forces were studied, using our modified model. A precise calculation of
the perturbations is possible only if the initial orbit is sufficiently well known.
Orbital elements that have been entered hp=3000Km., inclination= 63ᵒ, 23ᵒ and
eccentricity= 0.1, longitude of ascending node 30ᵒ, argument of perigee 40ᵒ where
the orbital elements will deviate from initial values with time through 3000 days.
Newton-Rapson method was used to calculate the position and velocity with out
perturbation . The perturbed equation of motion solved numerically using

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Publication Date
Mon Sep 28 2020
Journal Name
Journal Of Physical Education
The Effect of Increasing Rehabilitation Program Using Electric Stimulation On Rehabilitating Knee Joint Working Muscles Due to ACL Tear In Athletes
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The research aimed at designing a rehabilitation program using electric stimulation for rehabilitating knee joint working muscles as a result of ACL tear using an apparatus developed by the researchers that stimulate the muscle vibration and work as well as the ability to rehabilitate the join in shorter periods. In addition to that, it aimed at identifying the effect of this program on rehabilitating the knee joint working muscles. The researchers used the experimental method on Baghdad clubs’ players who suffer from complete knee joint ACL tear aged (19 – 24) years old. The results showed that the training program developed the working muscles significantly achieving normal levels of activity.

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Publication Date
Fri Jan 31 2025
Journal Name
Journal Of Physical Education
The Effect of Increasing Rehabilitation Program Using Electric Stimulation On Rehabilitating Knee Joint Working Muscles Due to ACL Tear In Athletes
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