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Effect of modified nanohydroxyapatite fillers addition on some properties of heat cured acrylic denture base materials
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Background: Poly (methylmethacrylate) is not ideal in every aspect and has disadvantages such as insufficient surface hardness, increase water sorption and poor impact resistance and the latter being the primary cause of fracture of denture base resins. The aim of this study was to evaluate the effect of addition of silanized nano- hydroxyapatite (HA) on some properties of heat cured acrylic denture base material. Materials and methods: HA nano particles were first silanized with MPS (tri methacryloxypropyletrimethoxy silane coupling agent) then ultrasonicated with methylmethacrylate (monomer) to disperse agglomerated nano particles and mixed with polymer. 2% by wt of HA nano particles was selected as the best concentration that added to the denture base material according to the pilot study.(100) specimens were prepared by conventional water bath processing technique and divided to two groups: 50 specimens for control group or 0% HA and 50 for experimental group or 2% HA then each group was subdivided to five groups with 10 specimens for each test: impact strength, transverse strength, surface hardness, surface roughness, water sorption and water solubility. Results: highly significant increase in impact strength and surface hardness after addition of 2% HA nano particles but not significant decrease in water sorption whereas solubility was significantly decreased. Surface roughness was significantly increased as compared with control group but remained within the acceptable limit less than 2m. HA nanoparticles addition highly decreased the transverse strength value. Conclusion The addition of 2% HA nano particles considerably improved the impact strength, surface hardness and had positive effect on water sorption and solubility. Whereas the same concentration tend to highly decreased transverse strength and increase surface roughness.

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Publication Date
Tue Jun 14 2005
Journal Name
Iraqi Journal Of Laser
Design and Operation of Mini-TEA CO2 Laser and Investigation of Preionization Effect
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A Mini-TEA CO2 laser system was designed and operated to obtain a pulse at 10.6 μm. Output energy of 30 mJ, with preionization pins, and pulse duration of 100ns were obtained. While an output energy of 6mJ and pulse duration of 100 ns in absence of pre-ionization were obtained. The system was operated with Ernest profile main-discharge electrodes. Dependencies of supply voltage and output laser energy on the pressure inside laser cavity were investigated as well as dependencies of supply voltage and output energy on the main capacitor(8CO2 : 8N2 : 82He :2CO). Efficiency of was calculated to be 4.4%.

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Publication Date
Fri Jun 16 2023
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Lipid -Lowering Effect of Polysaccharide (Pectin) of Viscum album L. Plant in Rats
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Disturbances of lipid metabolism is a predisposing factor of cardiovascular diseases, which are accompanied by high mortality rates of the population - ischemic heart disease and ischemic stroke. Plant polysaccharides can be promising remedies for correction of lipid imbalance.

In this regard, the aim of the study was to assess the hypolipidemic activity of polysaccharides isolated from the leaves of mistletoe.

The test-object was the leaves of the white mistletoe (Viscum album L.) growing on the apple (Malus domestica Borkh.), and the pear (Pyrus communis L.). Polysaccharides (water-soluble polysaccharides and pectin substances) were quantitatively determined by the gravimetric method followed

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Publication Date
Sun Dec 10 2023
Journal Name
Journal Of Kufa For Chemical Sciences
Study Of Effect Adsorption Of E127 Dye By Iraqi Clay From Aqueous Solution
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Abstract The surface of kaolin was diagnosed by an AFM and the results were shown The height of the highest peak reached by a quantity of Kaolin ‎surface is 2.5 µm, the granules, and their diameter with an average diameter of 666.1nm. Using Kaolin's adsorption properties, erythrosine was removed of its aqueous solution. It was determined that the maximal dye adsorption ranged 36.53–40.61%. ‎‎‎‎The results of using the Freundlich, Langmuir, and Temkin adsorption isotherms revealed that at temperatures of (298,308,318) K, the Freundlich model was followed, the Langmuir model did not match, and the Temkin model could only be partially applied. There is also physical adsorption. One of the three kinetic models of the

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Publication Date
Sat Feb 02 2019
Journal Name
Journal Of The College Of Education For Women
The Information Effect in Iraqi Universities: The Information Effect in Iraqi Universities
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Abstract:
This research (The effect of information in Iraqi universities) wants to
explain the aims and the opinions of Iraqi universities lecturers during the
globalization era and information technology .
The results we have got about using the computers by the lecturers of
Iraqi universities just in illustration and statistic as depends on there works

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Publication Date
Sat Dec 26 2020
Journal Name
International Journal Of Pharmaceutical Research
Complexes of Co(II), Cu(II), Ni(II), Pt(II) And Pd(II) with N 3 O-Chelating Ligand Incorporating Azo and Schiff Base Moieties: Synthesis, Spectroscopic, Thermal Decomposition, Theoretical Studies, and thermodynamic parameters
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Publication Date
Thu Mar 25 2021
Journal Name
International Journal Of Drug Delivery Technology
Synthesis, Structural Study, and Biological Activity Evaluation of VO(II), Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) Complexes with New Schiff Base Ligand Derived from Pyrazine
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New Schiff base [3-(3-acetylthioureido)pyrazine-2-carboxylic acid][L] has been prepared through 2 stages, the chloro acetyl chloride has been reacting with the ammonium thiocyanate in the initial phase for producing precursor [A], after that [A] has been reacting with the 3-amino pyrazine-2-carboxilic acid to provide a novel bidentate ligand [L], such ligand [L] has been reacting with certain metal ions in the Mn(II), VO(II), Ni(II), Co(II), Zn(II), Cu(II), Hg(II), and Cd(II) for providing series of new metal complexes regarding general molecular formula [M(L)2XY], in which; VO(II); X=SO4,Y=0, Co(II), Mn(II), Cu(II), Ni(II), Cd(II), Zn(II), and Hg(II); Y=Cl, X=Cl. Also, all the compounds were characterized through spectroscopic techniques [

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Educational And Psychological Researches
The Level of Academic Achievement and its Relationship with Some Characteristics of Female Students at College of Education for Girls in Baghdad University: The Level of Academic Achievement and its Relationship with Some Characteristics of Female Students at College of Education for Girls in Baghdad University
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Abstract

Personality is one of the most important elements that should be developed in university student. Thus, we have to develop the positive traits and neutralize the negative traits of students as well as we have to pay attention to the level of student achievement at the same time, the researcher designed a scale to measure the traits of study sample. The research come out with a number of recommendations and proposals, the most important of which Enhancing the positive characteristics of university students in order to reach them to the level of mature personality with mental health. Enhancing the positive role of the high level of achievement by motivating the stude

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Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Engineering
Study the Properties of Sodium Silicate Composite as a Barrier Separating Between the Internal Oil Distillation Towers and Chemical Fumes of Crude Oil
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The study of surface hardness, wear resistance, adhesion strength, electrochemical corrosion resistance and thermal conductivity of coatings composed from sodium silicate was prepared using graphite micro-size particles and carbon nano particles as fillers respectively of concentration of (1-5%), for the purpose of covering and protecting the oil distillation towers. The results showed that the sodium silicate coating reinforced with carbon nano-powder has higher resistance to stitches, mechanical wear, adhesive and thermal conductivity than graphite/sodium silicate composite especially when the ratio 5% and 1%, the electrochemical corrosion test confirmed that the coating process of stainless steel 304 lead to increasin

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Publication Date
Mon Feb 25 2019
Journal Name
Iraqi Journal Of Physics
Comparison study of CC and CH vibration frequencies and eelectronic properties for mono, Di, Tri, and tetra-rings layer of arm chair (SWCNTs)
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Semi-empirical methods were applied for calculating the vibration frequencies and IR absorption intensities for normal coordinates of the {mono (C56H28), di (C84H28), tri (C112H28) and tetra (C140H28)} -rings layer for (7,7) armchair single wall carbon nanotube at their equilibrium geometries which were all found to have D7d symmetry point group.

Assignment of the modes of vibration (3N-6) was done depending on the pictures of their modes by applying (Gaussian 03) program. Comparison of the vibration frequencies of (mono, di, tri and tetra) rings layer which are active in IR, and inactive in Ramman spectra. For C-H stretching vibrat

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Publication Date
Tue Sep 11 2018
Journal Name
Iraqi Journal Of Physics
Characterization of thermo-physical and hardness properties of unsaturated polyester resin hybrid nano composites Sihama Issa Salih1, Waleed Bdaiwi Salih2, Husam Sakin Hamad2
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In this work, two groups of nanocomposite material, was prepared from unsaturated polyester resin (UPE), they were prepared by hand lay-up method. The first group was consisting of (UPE) reinforced with individually (ZrO2) nanoparticles with particle size (47.23nm). The second group consists of (UPE) reinforced with hybrid nanoparticles consisting of zirconium oxide and yttrium oxide (70% ZrO2 + 30% Y2O3) with particles size (83.98nm). This study includes the effect of selected volume fraction (0.5%, 1%, 1.5%, 2%, 2.5%, 3%) for both reinforcement nano materials. Experimental investigation was carried out by analyzing the thermo-physical properties like thermal conductivity, thermal diffusivity and specific heat for the polymeric composit

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