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Properties of High Performance Concrete
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The research deals with a new type of high-performance concrete with improved physical properties, which was prepared by using metal additives minutes (Metakaolin) and by studing their impact on the properties of mortar and concrete high-performance through destructive and non destructive tests. This type of concrete is used broadly in public buildings and in other structures . The research involved a number of experiments such as finding the activity index of burned at a temperature of 750 º C according to the standard ( ASTM C-311/03), as well as casting models for the cubic mortar mixtures and concrete containers at different rates of metakaolin ranging between (5% - 20%) as an added part to the cement mix to get a high- compressive strength concrete reaching more than (70) N/mm2 in addition to the decrease in porosity. The research includes standying engineering properties such as density and compressive strength and ultrasonic pulse velocity test and dynamic modulus of elasticity and porosity.

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Publication Date
Fri Mar 31 2017
Journal Name
Journal Of Engineering
hermo-Physical and Mechanical Properties of Unsaturated Polyester /Cobalt Ferrite Composites
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Unsaturated polyester was used as a matrix which was filled with different percentages of cobalt ferrite using hand lay-up method. Cobalt ferrite was synthesized using solid state ceramic method with reagent of CoO and Fe2O3. Mechanical properties such tensile strength, Young's modulus and shore D hardness of the composite have been studied. All these properties have increased by 10% with increasing cobalt ferrite contents. Also the thermal properties such thermal conductivity and specific heat capacity are highly increased as the ferrite content increased, while the thermal diffusivity increased by 22 %. On the other hand dielectric strength of composite has been measured which increased by 50% by increasing the cobalt ferrite content.&

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Publication Date
Thu Sep 01 2022
Journal Name
Physical Chemistry Research
Dielectric Properties of Ultra-Low Dielectric Constant PVA-Pentaerythritol/MnO2 Nanocomposite
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this work, a simple method was used to prepare the MnO2 nanoparticles. These nanoparticles then were characterized by several techniques, such as X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and atomic force microscope (AFM). The results showed that the diffraction peak of MnO2 nanoparticles was similar to that of standard data. The images of AFM and SEM indicated that the MnO2 nanorods were growing from the MnO2 nano spherical shape. PVA-pentaerythritol/MnO2 nanocomposite films were fabricated by evaporating casting method. The dielectric constant and loss tangent of P-Ery/MnO2 films were measured between 10 kHz and 1 MHz using LCR. As the content of MnO2 increased, the dielectric constant

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Publication Date
Sun Feb 24 2019
Journal Name
Iraqi Journal Of Physics
Morphology, chemical and electrical properties of CdO Nanoparticles on porous silicon
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In this paper, CdO nanoparticles prepared by pulsed laser deposition techniqueonto a porous silicon (PS) surface prepared by electrochemical etching of p-type silicon wafer with resistivity (1.5-4Ω.cm) in hydrofluoric (HF) acid of 20% concentration. Current density (15 mA/cm2) and etching times (20min). The films were characterized by the measurement of AFM, FTIR spectroscopy and electrical properties.

  Atomic Force microscopy confirms the nanometric size.Chemical components during the electrochemical etching show on surface of PSchanges take place in the spectrum of CdO deposited PS when compared to as-anodized PS.

The electrical properties of prepared PS; namely current density-voltage charact

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Publication Date
Mon Oct 01 2012
Journal Name
Iraqi Journal Of Physics
Synthesis and study the electrical properties of carbon nanotubes- polyvinylchloride composites
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The aim of this paper, study the effect of carbon nanotubes on the electrical properties of polyvinylchloride. Samples of polyvinylchloride carbon nanotubes composite prepared by using hot press technique. The weight percentages of carbon nanotubes are 0,5,10 and 20wt.%. Results showed that the D.C electrical conductivity increases with increasing of the weight percentages of carbon nanotubes. Also, the D.C electrical conductivity changed with increase temperature for different concentrations of carbon nanotubes. The activation energy of D.C electrical conductivity is decreased with increasing of carbon nanotubes concentration.

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Publication Date
Fri Feb 14 2025
Journal Name
Edelweiss Applied Science And Technology
Spectroscopic investigation of thermo and kinetic properties for lithium-sulfur electrolytes
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The development of advanced lithium-sulfur (Li-S) batteries has gathered noteworthy attention due to their high theoretical energy density and potential for use in next-generation energy storage systems. This study focuses on the thermodynamic and dynamic analysis of advanced Li-S battery electrolytes using spectroscopic methods. By employing techniques such as nuclear magnetic resonance (NMR), Raman spectroscopy, and infrared (IR) spectroscopy, the research explores the interaction mechanisms between lithium ions and sulfur compounds within various electrolyte formulations. The results provide insights into the solvation structures, ion transport properties, and the stability of intermediates, which are significant for improving th

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Publication Date
Tue May 01 2012
Journal Name
Iraqi Journal Of Physics
Nano-Scale core effects on electronic structure properties of gallium arsenide
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Ab – initio density function theory (DFT) calculations coupled with Large Unit Cell (LUC) method were carried out to evaluate the electronic structure properties of III-V zinc blend (GaAs). The nano – scale that have dimension (1.56-2.04)nm. The Gaussian 03 computational packages has been employed through out this study to compute the electronic properties include lattice constant, energy gap, valence and conduction band width, total energy, cohesive energy and density of state etc. Results show that the total energy and energy gap are decreasing with increase the size of nano crystal . Results revealed that electronic properties converge to some limit as the size of LUC increase .

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Publication Date
Mon May 02 2022
Journal Name
Neuroquantology
Manufacturing and Improving Engineering Properties of Silica Bricks from Raw Materials
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Refractories are mineral and chemical-, based, materials with excellent heat resistance, making them ideal for use in the construction of ovens, furnace walls industries. According to this our research is concerned to study the effect of addition of (4% CaO) and (5% graphite) on the silica brick properties. Different amounts of CaO and Graphite were included in the white sand (raw ingredients) of silica bricks as a binder to prepare the composition then the composition were sintered using Different sintering temperatures ranging from (1000–1400)𝛐C under static air. Density, thermal conductivity, porosity, and water absorption Compression there was power tested after sintering. XRD analysis was used to identify raw materials’

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Publication Date
Sun Jan 01 2017
Journal Name
J. Of University Of Anbar For Pure Science
Synthesis , characterization and electrical properties of conductive polyaniline/ functionalized MWCNT nanocomposites
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by in situ polymerization of aniline monomer, conducting polyaniline (PANI) nanocomposites containing various concentrations of carboxylic acid functionalized multi-walled carbon nanotubes (f-MWCNT) were synthesized. The morphological and electrical properties of pure PANI and PANI /MWCNT nanocomposites were examined by using Fourier transform- infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Atomic Force Microscopy (AFM) respectively. FTIR spectra shows that the carboxylic acid groups formed at the both ends of the sidewalls of the MWCNTs. The aniline monomers were polymerized on the surface of MWCNTs, depending on the -* electron interaction between aniline monomers and MWCNTs and hydrogen bonding into interaction between t

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Publication Date
Sun Apr 08 2018
Journal Name
Al-khwarizmi Engineering Journal
Physical and Morphological Properties of Hard- Soft Ferrite Functionally Graded Materials
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  Functionally graded materials (FGMs), with ceramic –ceramic constituents are fabricated using powder technology techniques. In this work three different sets of FGMs samples were designed in to 3 layers, 5 layers and 7 layers. The ceramic constituents were represented by hard ferrite (Barium ferrite) and soft ferrite (lithium ferrite). All samples sintered at constant temperature at 1100oC for 2 hrs. and characterized by FESEM. Some physical properties were measured for fabricated FGMs include apparent density, bulk density, porosity, shrinkage and hardness. The results indicated that the density increase with the increase the number of layer. Lateral shrinkage is one of the important parameter f

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Effect of growth regulators on sex expression and some quantitatve properties
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This study was conducted in an orchard pomegranate's Department of Horticulture College of Agriculture, University of Baghdad for two seasons 1999-2000 on cultivars pomegranate Salimi and narrators seedless to study the effect spraying Nizant growth in sex ratio of flowers and recipes flowering and winning was selected 27 trees per class 15 years old planted

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