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Effect of Nano Powder on Mechanical and Physical Properties of Glass Fiber Reinforced Epoxy Composite
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Fiber reinforced polymer composite is an important material for structural application. The diversified application of FRP composite has taken center of attraction for interdisciplinary research. However, improvements on mechanical properties of this class of materials are still under research for different applications. In this paper we have modified the epoxy matrix by Al2O3, SiO2 and TiO2 nano particles in glass fiber/epoxy composite to improve the mechanical and physical properties. The composites are fabricated by hand lay-up method. It is observed that mechanical properties like flexural strength, hardness are more in case of SiO2 modified epoxy composite compare to other nano modifiers, were physical properties like density, water absorption are more in case of TiO2 modified epoxy composite. This may be because of smaller particle size of silica compare to others.

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Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Engineering
Effect of Thickness Variable on the Bending Analysis of Rotating Functionally polymer Graded Carbon Nanotube Reinforced Cylindrical Panels
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This study offers the elastic response of the variable thickness functionally graded (FG) by single walled carbon nanotubes reinforced composite (CNTRC) moderately thick cylindrical panels under rotating and transverse mechanical loadings. It’s considered that, three kinds of distributions of carbon nanotubes which are uniaxial aligned in the longitudinal direction and two functionally graded in the transverse direction of the cylindrical panels. Depending on first order shear deformation theory (FSDT), the governing equations can be derived. The partial differential equations are solved by utilizing the technique of finite element method (FEM) with a program has been built by using FORTRAN 95. The results are calculat

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Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Synthesis and Characterization of Some New Monemer and Polymers Containing Hetero Cyclic Rings With Study of Their Physical Properties.
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Number of new polyester and polyamide are prepared as derivatives from 5,5`-(1,4-phenylene)-bis-(1,3,4-thiadiazole-2-amine) [C1], three series of heterocyclic compounds were synthesized.The first series includes the Schiff base [C2] prepared from the reaction between compound [C1] with p-hydroxy benzaldehyde in presence of acetic acid and absolute ethanol , then these derivatives have reaction with maleic anhydride , phthalic anhydride and sodium azide, respectively to obtain the compounds [C3-5] contaning (oxazepine and tetrazole) rings.The third series of compounds [C1-5] has transformed to their polymers [C6-15] by reaction with adipoyl chloride and glutroyl chloride , respectively. The reaction was followed by T.L.C and ident

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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
Mon Aug 01 2022
Journal Name
مجلة الرافدين للعلوم الرياضية
Fartlek exercises and their effect on molecular biology (vascular endothelial growth factor-basic fibroblast growth factor) and some physical variables for players 800m arena and field for youth
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The study aimed to : - To determine whether there are significant differences between Fartlek training and the increase in the molecular biology (VEGF - basal fibroblast growth factor) for arena and field players in an (800m) youth event. - Determine whether there are statistically significant differences between Fartlek training and the increase in molecular biology and some physical variables for the players (800m) in the arena and field for youth. - Determine whether the Fartlek training method is the most appropriate to achieve statistically significant differences in the research variables for the players (800m) in the arena and field for youth. The researchers used the experimental method for its suitability and the nature of the rese

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Publication Date
Mon Dec 01 2008
Journal Name
Al-khwarizmi Engineering Journal
Effect of Chloride Ions on the Corrosion Behavior of Al – Zn Alloy in NaOH Solution at Four Different Temperatures
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This research involves study effect of chloride ions in concentration range (0.01 – 0.50 mol.dm-3) on the corrosion behavior of Al-Zn alloy in basic media of 1x10-3 mol.dm-3 NaOH at pH=11 and four different temperatures in the range (298-313 K). Cathodic and anodic Tafel slopes (bc &ba) and transfer coefficients (αc & αa) were calculated and the results interprets according to the variation of the rate – determining steps. The results also indicate that the chloride ions are bonded chemically in the interface as an initial step of formation of different mixed oxohydroxy – and chloro complexes. Polarization resistance (Rp) is calculates

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Publication Date
Wed Sep 01 2021
Journal Name
Baghdad Science Journal
Effect of Testosterone Enanthate Modeling of Polycystic Ovary on Liver Irs-2 mRNA Expression in Rats: A Brief Report
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There are many animal models for polycystic ovary (PCO); using exogenous testosterone enanthate is one of the methods of induction of these models. However, induction of insulin resistance should also be studied in the modeling technics. Therefore, the present study aims to investigate the expression of insulin receptor substrate (Irs)-2 mRNA in the liver tissue of rat PCO model. Nineteen Wistar rats were divided into three groups; (1) PCO modeling group (N =7) received daily 1.0 mg/100g testosterone enanthate solved in olive oil along with free access dextrose water 5%, (2) vehicle group (N =6), which handled like the PCO group, but did not receive testosterone enanthate, (3) control group (N =6) with standard care. Al

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Publication Date
Mon Jan 18 2021
Journal Name
Materials Science And Engineering
Properties of engineered cementitious composite concrete (bendable concrete) produced using Portland limestone cement
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Bendable concrete, also known as Engineered Cementitious Composite (ECC) is a type of ultra-ductile cementitious composites reinforced with fibres to control the width of cracks. It has the ability to enhance concrete flexibility by withstanding strains of 3% and higher. The properties of bendable concrete mixes (compressive strength, flexural strength, and drying shrinkage) are here assessed after the incorporation of supplementary cementitious materials, silica fume, polymer fibres, and the use of ordinary Portland cement (O.P.C) and Portland limestone cement (IL). Mixes with Portland limestone cement show lower drying shrinkage and lower compressive and flexural strength than mixes with ordinary Portland cement, due to the ratio o

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Publication Date
Fri Nov 29 2019
Journal Name
Iraqi Journal Of Physics
Gas Sensing of (SnO2)1-x(ZnO)x Composite Associating with Electrical Properties
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Abstract

Semiconductor-based gas sensors were prepared, that use n-type tin oxide (SnO2) and  tin oxide: zinc oxide composite (SnO2)1-x(ZnO)x at different x ratios using pulse laser deposition at room temperature. The prepared thin films were examined to reach the optimum conditions for gas sensing applications, namely X-ray diffraction, Hall effect measurements, and direct current conductivity. It was found that the optimum crystallinity and maximum electron density, corresponding to the minimum charge carrier mobility, appeared at 10% ZnO ratio. This ratio appeared has the optimum NO2 gas sensitivity for 5% gas concentration at 300 °C working temperat

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Publication Date
Sun Feb 25 2024
Journal Name
Baghdad Science Journal
The Effect Of Optimizers On The Generalizability Additive Neural Attention For Customer Support Twitter Dataset In Chatbot Application
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When optimizing the performance of neural network-based chatbots, determining the optimizer is one of the most important aspects. Optimizers primarily control the adjustment of model parameters such as weight and bias to minimize a loss function during training. Adaptive optimizers such as ADAM have become a standard choice and are widely used for their invariant parameter updates' magnitudes concerning gradient scale variations, but often pose generalization problems. Alternatively, Stochastic Gradient Descent (SGD) with Momentum and the extension of ADAM, the ADAMW, offers several advantages. This study aims to compare and examine the effects of these optimizers on the chatbot CST dataset. The effectiveness of each optimizer is evaluat

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Publication Date
Thu Nov 02 2017
Journal Name
Iraqi Journal Of Laser
Enhancement the Sensitivity of Humidity Sensor Based on an Agarose Coating Transmission-Type Photonic Crystal Fiber Interferometer
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Photonic Crystal Fiber Interferometers (PCFIs) are widely used for sensing applications. This work presents the fabrication and the characterization of a relative humidity sensor based on a polymer-coated photonic crystal fiber that operates in a Mach- Zehnder Interferometer (MZI) transmission mode. The fabrication of the sensor involved splicing a short (1 cm) length of Photonic Crystal Fiber (PCF) between two single-mode fibers (SMF). It was then coated with a layer of agarose solution. Experimental results showed that a high humidity sensitivity of 29.37 pm/%RH was achieved within a measurement range of 27–95%RH. The sensor also showed good repeatability, small size, measurement accuracy and wide humidity range. The RH sensitivity o

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