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ijs-4864
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
Mon Jul 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Antibacterial Activity of PEG Polycyclic Acetal Metal Complex/ PVA Polymer Blend Film
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     Polyacetal was synthesized from the reaction of Polyethylene glycol with4- dimethylaminobenzaldehyde.Polymer metal complex was synthesized by the reaction with Ag+; polymer blend with polyvinyl alcohol was synthesized solution casting technique. All synthesized compounds were characterized by FT-IR in addition to the antimicrobial activity. The FT-IR spectra indicate the formation of the polyacetal. The DSC resultsindicatethe thermal stability regarding the synthesized polymer blends. The synthesized polyacetal, its metal complex and PA blend against four types of bacteria (gram+ve) Staphylococcus aureas, Bacillus subtilis and (gram –ve)Klebsiella pneumoniae, Escherichia Coli w

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Publication Date
Wed Dec 26 2018
Journal Name
Iraqi Journal Of Science
Design of New Dynamic Cryptosystem with High Software Protection
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     In this paper a design of new robust and dynamic cryptosystem using stream key generator with good random statistical properties is introduced. The results of the statistical tests, initialization and the components of the proposed generator of the suggested cryptosystem are detailed in [1]. The proposed cryptosystem called Robust and Efficient Dynamic Stream Cipher Cryptosystem (RDSCC). The dynamic here means the generator of RDSCC has unfixed construction; the design will be changed as the seed (initial) key changed. The generator will construct itself by barrows number of Linear Feedback Shift Registers (LFSR’s), randomly, stored in protected bank file. The RDSCC is constructed to be flexibl

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Publication Date
Sat Jan 12 2013
Journal Name
International Journal Of Advanced Research In Engineering And Technology (ijaret)
FABRICATION OF AGAL/SI SOLAR CELL
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The structural, optical and photoelectrical properties of fabricated diffusion heterojunction (HJ) solar cell, from n-type c-Si wafer of [400] direction with Boron, has been studied. AgAl alloys was used because of its properties that affect as a good connection materials. TiO2 has been used as a reflecting layer to increase the absorption radiation. The HJ has direct allowed energy gap equal to 3.1 eV. The c-Si/B HJ solar cell yielded has an active area conversion efficiency of 16.4% with an open circuit voltage of (Voc) 0.592V, short circuit current (Isc) of 2.042mA, fill factor (F.F) of 0.682 and % =10.54.

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Fabrication of multi-junction solar cells
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Fabrication of solar cell prepared by thermal spray and vacuum thermal evaporation method on silicon wafer(n-type) and studying its efficiency. The film have been deposited on three layers(ZnO then CdS and CdTe) on Si and glass respectively.Direct energy gap was calculated and equal to (4.3,3.4,3)eV and indirect energy gap equal to (3.5,2.5,1.5)eV respectively . Efficiency was calculated for the cell of area 2cm2 it was equal to 0.14%.

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Publication Date
Mon Jan 01 2018
Journal Name
American Institute Of Physics
Fabrication of AgInSe2 heterojunction solar cell
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Abstract. Silver, Indium Selenium thin film with a thickness (5001±30) nm, deposited by thermal evaporation methods at RT and annealing3temperature (Ta=400, 500 and 600) K on a substrate of glass to study structural and optical properties of thin films and on p-Si wafer to fabricate the AgInSe2/p-Si heterojunction solar cell. XRD analysis shows that the AgInSe2 (AIS) deposited film at RT and annealing3temperature (Ta=400, 500 and 600) K have polycrystalline structure. The average grain size has been estimated from AFM images. The energy gap was estimated from the optical transmittance using a spectrometer type (UV.-Visible 1800 spectra photometer). From I-V characterization , the photovoltaic parameters such as, open-circuit voltage, short

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Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Physical and Mechanical Properties of Synthesized Doped Nanoferrite
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Nanoferrite materials have been synthesized by sol-gel auto combustion method. The effect of doping different percentages of Y2O3 (0.34 µm) on the physical and mechanical properties of selected mixed ferrite [(Li2.5Fe0.5) 0.9(Co4Fe2O4) 0.1] by adding 10% Cobalt ferrite was studied. Physical properties (i.e. .density, porosity and water absorption) were affected by the doping, where the density increased about 32% at 6 wt% Y2O3, while porosity has a drastically decreased about 80% at 6% Y2O3 and has a correlation effect on the mechanical properties(Splitting  tensile strength and Vicker

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Publication Date
Sun Jun 02 2013
Journal Name
Baghdad Science Journal
Extraction and Determination of Amygdaline in Iraqi Plant Seeds Using the Combined Simple Extraction Procedure and High-Performance Liquid Chromatography
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Abstract :In this study, amygdaline in Iraqi plant seeds was extracted and isolated from their seeds matrix using reflux procedure and subsequently identified and determined by high performance liquid chromatography (HPLC) on reversed phase column of LC-18 (150mm x 4.6mm, 5?m )with actonitrile :water ( 50 : 50 ) as mobile phase at flow rate of ( 0.5 mL/min ) and detection at wavelength of 215 nm.The experimental results indicated that the linearity of calibration is in the range of 1.0-30.0 mg L-1amygdaline with the correlation coefficient of 0.9949. The limit of detection (LOD) and limit of quantitation (LOQ) for amygdaline were of 0.88 and 2.93 mg L-1 in standard pure sample. The mean recovery percent is 97.34±0.58 at 95% confidence inte

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Publication Date
Sat Sep 01 2018
Journal Name
Iraqi Journal Of Science
Polymer optical fiber sensor side-pumped with polymer clad doped lasing compounds
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Publication Date
Sun Dec 08 2019
Journal Name
Journal Of Global Pharma Technology
Effect of Functionalized Graphene Oxide (FGO) on the Electrical and Dielectrical Properties of PVA Films
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In the present work, nanocomposite of poly (vinyl alcohol) (PVA) incorporated with functionalized graphene oxide (FGO) were fabricated using casting method. PVA was dispersed by varying content of FGO (0.3, 0.5, 0.8, 1 wt %). The PVA- FGO nanocomposite was characterized by FT‐IR, FE-SEM and XRD. Frequency dependence of real permittivity (ε’), imaginary (ε’’) and a.c conductivity of PVA/FGO and PVA/GO nanocomposite were studied in the frequency range 100 Hz- 1 MHz. The experimental results showed that the values of real (ε’) and imaginary permittivity (ε’’) increased dramatically by increasing the FGO content in PVA matrix. PVA/ FGO (1 wt %) nanocomposite revealed higher electrical conductivity of 6.4×10-4 Sm-1 compared to

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Publication Date
Sat Sep 30 2023
Journal Name
Iraqi Journal Of Science
Determination of Alkaloids Constituents in Some Ferns by Using High Performance Liquid Chromatography Technique – Iraq
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    Ferns are considered as important medical herbs. They produce a wide range of secondary metabolites that could be useful in treating different diseases. However, they still remain underexplored in medical aspects in Iraq. Hence, the purpose of this study was to identify alkaloids components in the methanol extracts of four fern species (Asplenium ceterach L., A. scolopendrium L., Cheilanthes pteridioides (Richard) C. Chr. from Malakan region in Erbil Governorate and Equisetum ramosissimum Desf. from Chemi Rezan in Sulaimaniyah Governorate,  of northen Iraq during March - June 2018. The research was conducted by using High performance liquid chromatography (H

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