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Fabrication and Characterization of High-Performance Crosslinked PVA/ PMDA Doped with H2SO4
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     In the present study, pure Poly(viny1 alcohol) (PVA) and  pyromellitic dianhydride (PMDA) cross linked PVA with (0,5,10,15 and 20)wt.% and doped with different molarity (5,9)M of sulfuric acid (H2SO4) were prepared by the solution casting method and were characterized as a function of  frequency in the range (1-100) KHz.

     The FT-IR results showed that the strong broad band observed at 3738.05 and 3857.63 cm-1 may be assigned to O-H stretching due to the strong hydrogen bond of intramolecular and intermolecular type in PVA film.  When PVA is doped with 5M and 9M H2SO4,  a new peak was noticed at 813 cm-1, this peak may be due to the formation of hydrogen bond between the carbonyl (C=O) group of PVA and the H+ ion from the acid.

      As the PMDA concentration increases, the peak intensity of the O–H band 3738.05 cm−1 gradually decreases due to the reaction of more –OH groups of the PVA molecules with the –COOH group. Hence, it is difficult for the crosslinked PVA polymer chains to pack and form crystal regions, so the crosslinked PVA polymer chains become more flexible.

        The a.c. conductivity increases with the increase of frequency. FTIR spectra specified that the chemical reaction did occur between the PVA and the acid, therefore  hydrogen ion (H+) can easily be  separated from the carbonyl group and become free to move which explains proton conductivity of PVA.

    The increase of PMDA concentration has increased free volume and ionic mobility in the film with increasing cross-linkages.

     Dielectric constant decreases with increasing H2SO4 molarity for every frequency.

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Publication Date
Thu Oct 14 2021
Journal Name
Iraqi Journal Of Physics
Investigation of nonlinear optical properties for laser dyes-doped polymer thin film
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Solutions of dyes Rhodamine 6G (Rh6G) and Coumarin480(C480) were prepared at five concentrations (1x10-3, 5x10-4, 1x10-4, 5x10-5 and1x10-5) mol/l, the mixing was stirred to obtain on a homogenous solution, the(poly methyl-methacrylate) (PMMA) was solved by chloroform solvent with certain ratio, afterward (PMMA+Rh6G) and (PMMA+C480) thin films were prepared by casting method on glass block which has substrate with dimensions (7.5 x2.5)cm2, the prepared samples were left in dark place at room temperature for 24 hours to obtain uniform and homogenous thin films. UV-VIS absorption spectra, transmission spectra and fluorescence spectra were done to measure linear refractive index and linear absorption coefficient. The nonlinear optical proper

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Publication Date
Mon Mar 27 2023
Journal Name
Iranian Journal Of Materials Science And Engineering
First-Principles Analysis of Cr-Doped SrTiO 3 Perovskite as Optoelectronic Materials
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The influence of Cr3+ doping on the ground state properties of SrTiO 3 perovskite was evaluated using GGA-PBE approximation. Computational modeling results infered an agreement with the previously published literature. The modification of electronic structure and optical properties due to Cr3+ introducing into SrTiO 3 were investigated. Structural parameters assumed that Cr3+ doping alters the electronic structures of SrTiO 3 by shifting the conduction band through lower energies for the Sr and Ti sites. Besides, results showed that the band gap was reduced by approximately 50% when presenting one Cr3+ atom into the SrTiO 3 system and particularly positioned at Sr sites. Interestingly, substituting Ti site by Cr3+ led to eliminating the ban

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Publication Date
Thu May 18 2017
Journal Name
Semiconductor Science And Technology
Improving the optoelectronic properties of titanium-doped indium tin oxide thin films
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Publication Date
Sat Jun 01 2024
Journal Name
Computational Condensed Matter
Computational modeling study on the physical properties of Pd doped BaTiO3 perovskite
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This contribution investigates structural, electronic, and optical properties of cubic barium titanate (BaTiO3) perovskites using first-principles calculations of density functional theory (DFT). Generalized gradient approximations (GGA) alongside with PW91 functional have been implemented for the exchange–correlation potential. The obtained results display that BaTiO3 exhibits a band gap of 3.21 eV which agrees well with the previously experimental and theoretical literature. Interestingly, our results explore that when replacing Pd atom with Ba and Ti atoms at 0.125 content a clear decrease in the electronic band gap of 1.052 and 1.090 eV located within the visible range of electromagnetic wavelengths (EMW). Optical parameters such as a

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Publication Date
Sat Jun 27 2020
Journal Name
Iraqi Journal Of Science
Preparation and Characterization of Polymer Blends/ Kaolinite Nanoclay
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     In this research, we prepared a polymer blend of polyvinylalcohol (PVA)/carrageenan/kaolinite by means of the solution cast approach. The composition of the blend was PVA in 1 gm by weight with 0.2 gm carrageenan as a plasticizer. The ratio of nanoclay varied between 1 and 5 wt%. Different properties were investigated in this study such as water vapor permeability, hardness, tear strength, color stability, thermal stability, and antibacterial activity. Water vapor permeability was decreased with increasing the ratio of nanoclay, while the values of hardness, tear strength, color stability, and thermal stability were increased. Also, the antibacterial activity examination with two types of bacteria, e.g.

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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Numerical Study of Optimum Configuration of Unconventional Airfoil with Steps and Rotating Cylinder for Best Aerodynamics Performance
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Numerical study of separation control on symmetrical airfoil, four digits (NACA

0012) by using rotating cylinder with double steps on its upper surface based on the computation of Reynolds-average Navier- Stokes equations was carried out to find the optimum configuration of unconventional airfoil for best aerodynamics performance. A model based on collocated Finite Volume Method was developed to solve the governing equations on a body-fitted coordinate system. A revised (k-w) model was proposed as a known turbulence model. This model was adapted to simulate the control effects of rotating cylinder. Numerical solutions were performed for flow around unconventional airfoil with cylinder to main stream velocities ratio in the range

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Publication Date
Tue Jan 09 2024
Journal Name
Wasit Journal Of Sports Sciences
A Comparative Analytical Study of Some Biomechanical Variables and Their Relationship to The Accuracy of The Performance of The Shooting Skill of Jumping High in The Weak and Strong Foot the Players for Youth Handball
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The research aims to identify the most important variables affecting shooting from jumping high and compare them for the two foot the weak and strong, where the researchers adopted the descriptive method, and the sample was chosen by the intentional method, which consists of (4) players from the Iraqi Sports Army Club, where these variables were studied and their impact on The accuracy of aiming at the two men, and the researchers concluded that most of the players have more accuracy in aiming at the strong leg than at the weak leg, which leads to the loss of many real opportunities during the match because of the players changing the situation or wasting the available opportunity when the position of correction is an opportunity for the w

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Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Evaluation Interleukin ─ 8 and High Sensitivity C - Reactive Protein in Sera of Control Group and Human Female Patients with Osteoarthritis Nodal in Iraqi's Patients
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       The present study conducted on 30 female patients with osteoarthritis OA a attending Baghdad teaching hospital, in addition to 30 healthy females, all subjects were (35-65) year's old .Parameters were measured in the sera of patients group and healthy groups were interleukin -8 (IL-8) and high sensitivity C-reactive protein (hs-CRP).The results revealed a higher significant in all parameters of patients sera compared to healthy groups. Conclusion was obtained that IL-8 and hs- CRP were a markers or player inflammatory disease like osteoarthritis nodal  

 

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Publication Date
Mon Aug 26 2019
Journal Name
Iraqi Journal Of Science
Fabrication of TiO2 sensor using rapid breakdown anodization method to measure pressure, humidity and sense gases at room temperature
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Rapid breakdown anodization (RBA) process was used to fabricate TiO2 sensor to measure pressure and humidity and sense gases at room temperature. This chemical process transformed Ti to its oxide (TiO2) as a powder with amorphous phase as X ray diffraction (XRD) technique confirmed.  This oxide consisted from semi spherical nanoparticles and titania nanotubes (TNTs) as Scanning electron microscope (SEM) technique showed.  TiO2 powder was deposited on Ti substrates by using electrophoretic deposition (EPD) method.   Average pressure sensitivity was 0.34 MΩ/bar and hysteresis area was 1.4 MΩ .bar. Resistance of TiO2 decreased exponentially with the increasing of relative

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Publication Date
Sun Apr 01 2018
Journal Name
Research Journal Of Pharmaceutical, Biological And Chemical
Synthesis and characterization of azo dyes ligands complexes with Ni (II) and Cu (II) and studies their industrial and bacterial application
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1-[4-(4-Acetyl-2-hydroxy-phenylazo)-phenyl]-ethanone (L1) and 1-[3-Hydroxy-4(4-nitro-phenylazo)-phenyl]-ethanone (L2) were readied by combination the diazonium salts of amines with 3-hydroxyacetophenone. (C.H.N) analyses, infrared spectra, UV–vis electronic absorption spectra, 1H and 13CNMR spectral mechanisms are use to identified of the ligands. Complexes of Ni+2 and Cu+2 were performed as well depicted. The formation of complexes has been identified by using atomic absorption of flame, elemental analysis, infrared spectra and UV-Vis spectral process as well conductivity and magnetic quantifications. Nature of compounds produced have been studied obeyed the mole ratio and continuous contrast methods, Beer's law followed during a concent

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