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Studying the Mechanical Properties of Denture Base Materials Fabricated from Polymer Composite Materials
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In this research, the effect of adding two different types of reinforcing particles was investigated, which included: nano-zirconia (nano-ZrO2) particles and micro-lignin particles that were added with different volume fractions of 0.5%, 1%, 1.5% and 2% on the mechanical properties of polymer composite materials. They were prepared in this research, as a complete prosthesis and partial denture base materials was prepared, by using cold cure poly methyl methacrylate (PMMA) resin matrix. The composite specimens in this research consist of two groups according to the types of reinforced particles, were prepared by using casting methods, type (Hand Lay-Up) method. The first group consists of PMMA resin reinforced by (nano-ZrO2) particles, while the second group consists of PMMA resin reinforced by (micro-lignin) particles.

The mechanical tests performed in this research includedtensile test, compression test, impact test and hardness test. The results of this study showed that the values of tensile modulus of elasticity, compressive strength and hardness properties increased with increasing the volume fraction of these particles in PMMA composite materials. While, the values of tensile strength, elongation and impact strength properties decreased. Also, the addition of (nano-ZrO2) particles showed greater effect than that of (micro-lignin) particles in some properties of PMMA composite materials for prosthesis denture base materials specimens, while they have lower effect for the other properties.

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Publication Date
Wed Jan 01 2020
Journal Name
International Journal Of Innovation Creativity And Change.
The Role of Strategic Improvisation on the Entrepreneurial Orientation; a Field Study in a Sample from the Rafidain Bank
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The research aims to identify the role of strategic improvisation as an independent variable with its dimensions (Building the Solution, Intuition, Adaptation, and Spontaneity) and the Entrepreneurial Orientation as a dependent variable with its dimensions (Identifying Opportunities, Creativity, Adopting risk, and Vision). This research has been applied in the Rafidain Bank and its branches (Sunk, People, Al-Firdaws, and Alawiya); it used the questionnaire as a basic tool for collecting information. The sample was intentionality, which included all the heads of departments in the bank’s branches, which amounted to (33) workers, and data on the questionnaire paragraphs of 28 were processed using the SPSS V.23 and AMOS V.23). The most impor

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Publication Date
Sun Jun 30 2024
Journal Name
Modern Sport
Evaluating the Effectiveness of Using the Kinesthetic Teaching Style by Basketball Instructors in Practical Lessons from the Students' Perspective
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Advancements and modernizations introduced into the educational and pedagogical systems have significantly impacted teaching processes and how subjects are presented and explained to students. The focus has shifted to how learners interact with the material they need to learn, providing sufficient opportunities for learning and granting them freedom and self-confidence to achieve learning objectives. The research problem stems from the researcher's experience as a lecturer in the College of Physical Education and Sports Science, particularly in teaching basketball. She observed that some instructors were deficient in using the most effective teaching methods. The researcher formulated her research question based on these observations: "What

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Publication Date
Tue May 26 2026
Journal Name
Al–bahith Al–a'alami
Frameworks for international press coverage of external interference in the formation of the Iraqi government Analytical study for the Saudi Al-Sharq Al-Awsat and Kayhan Al-Arabi-Iranian newspapers for the period (1/1/2018 - 31/12/2018)
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This research deals with the frameworks and mechanisms of international press coverage of the issue of foreign interference in the formation of the Iraqi government in the Saudi newspapers Asharq Al-Awsat and Kayhan Al-Arabi Iran and how this topic was addressed in the two newspapers. The frameworks for international press coverage of external interference in the formation of the Iraqi government. ”This research is one of the descriptive research that adopted the survey method، which made it possible to use the content analysis tool to analyze
the content of the two newspapers، whose numbers are (624) from the
newspapers (Al-Sharq Al-Awsat Al-Saudi Arabia and Kayhan Al-Arabi Iran) from (1/1/2018 to 31/12/2018)، and the researc

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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Experimental Study of Drug Delivery system for Prednisolone Loaded and Released by Mesoporous Silica MCM-41
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In the present study, nanoporous material type MCM-41 was prepared by the sol-gel technique and was used as a carrier for prednisolone (PRD) drug delivery. The structural properties of mesoporous were fully characterized by X-ray diffraction (XRD), N2 adsorption /desorption and Fourier-transform infrared (FTIR). The mass transfer in term of adsorption process (loading) and desorption process (releasing) properties were investigated. The maximum drug loading efficiency was equal to 38% and 47.5% at different concentrations. The PRD released was prudently studied in water media of pH 6.8 simulated body fluid (SBF) in according to "United State Pharmacopeia (USP38)". The results proved that the release of prednisolone from MCM-41

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Publication Date
Fri Jan 19 2018
Journal Name
Journal Of Global Pharma Technology
Synthesis, Characterization and Study of Electrical Properties of Some New Aromatic Polyester
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This research discloses the synthesis of various polyester resins, the polyesters containing homoring aromatic and others heterocyclic were synthesized by the condensation polymerization of suitable monomers (which are containing variety function groups in different structures) with phthalic anhydride. The main objective is synthesis of new polyester with keeping a reasonable electrical insulating behavior. The structural of polymer was characterized by Fourier Transform infra-red spectroscopy FTIR and HNMR. The dielectric constant (real ε' and imaginary parts ε") and AC conductivity (σAC) for all the polyester samples are studied by varying the frequency (30, 50, 70, 90, 120, 300, 500Hz and 1KHZ) at 25⁰ C. Indeed, study of the electri

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Publication Date
Sun Apr 30 2017
Journal Name
Journal Of Engineering
Influence of Internal Sulfate Attack on Some Properties of Self Compacted Concrete
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      Self-compacted concrete (SCC) is a highly flowable concrete, with no segregation which can be spread into place by filling the structures framework and permeate the reinforcement without any compaction or mechanical consolidation ACI 237R-14. One of the most important problems faced by concrete industry in Iraq and Gulf Arab land is deterioration due to internal sulfate attack (ISA) that causes damage of concrete and consequently reduces its compressive strength, increases expansion and may lead to its cracking and destruction. The experimental program was focused to study two ordinary Portland cements with different chemical composition with (5, 10 and 15) % percentage of high reactivity metakaoline (HRM)

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Publication Date
Fri Mar 01 2013
Journal Name
Chemistry And Materials Research
Synthesis and Characterization of New Derivatives of Thiazole with Liquid Crystalline properties
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A new two series of liquid crystalline Schiff bases containing thiazole moiety with different length of alkoxy spacer were synthesized, and the relation between the spacer length and the liquid crystalline behavior was investigated. The molecular structures of these compounds were performed by elemental analysis and FTIR, 1HNMR spectroscopy. The liquid crystalline properties were examined by hot stage optical polarizing microscopy (OPM) and differential scanning calorimetry (DSC). All compouns of the two series display liquid crystalline nematic mesophase. The liquid crystalline behaviour has been analyzed in terms of structural property relationship

Publication Date
Tue Dec 01 2009
Journal Name
Iraqi Journal Of Physics
Study of Some Structural Properties of Porous Silicon Preparing by Photochemical Etching
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Abstract:Porous Silicon (PSi) has been produced in this work by using Photochemical (PC) etching process by using a hydrofluoric acid (HF) solution. The irradiation has been achieved using quartz- tungsten halogen lamp. The influence of various irradiation times on the properties of PSi اmaterial such as layer thickness, etching rate and porosity was investigated in this work too. The XRD has been studied to determine the crystal structure and the crystalline size of PSi material

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Publication Date
Mon Dec 05 2022
Journal Name
F1000research
Enhancement of surface properties of polyetheretherketone implant material by fractional laser texturing
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Background: Polyetheretherketone (PEEK) is a promising implant material due to its superior biomechanical strength. However, due to its hydrophobic nature and lack of cellular adhesion properties, it has poor integration with bone tissue. Methods: A fractional CO2 laser was used with various parameters for surface texturing of PEEK substrate to enhance its surface properties. An optical microscope and field-emission scanning electron microscope (FESEM) were used to examine the surface morphology of untextured and laser-textured samples. Energy dispersive X-ray spectroscopy (EDX) was performed to determine the effect of the laser on the microstructure of PEEK. Surface microroughness, atomic force microscopy (AFM), and wettability were invest

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Publication Date
Wed Sep 01 2021
Journal Name
Iraqi Journal Of Physics
Effect of π-conjugated molecules on electronics properties of benzene-diamine derivatives
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The present work shows a theoretical results that have been used the functional Hybrid of three parameters Lee-Yang-Parr (B3LYP) of the quantum mechanical approach for density functional theory with (Spanish Initiative for Electronic Simulations with Thousands of Atoms) SIESTA code. All calculations were carried out employing the used method at the Gaussian 09 package of programs. It was reported the main point for research on dominance of the bandgap of elongated pi-conjugated molecules by using different chemical groups replacing hydrogen atom in the most molecules that used in this work. The side groups creates another factor that controls the value of the band gap. The dihedral angle between the two pheny

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