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UV-Exposure effect on the mechanical properties of PEO/PVA blends
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     Poly ethylene oxide PEO / Poly vinyl alcohol PVA  blends were prepared by cast method at different ratios of (25%PEO/75%PVA, 30%PEO/70%PVA, 35%PEO/65%PVA, 40%PEO/60%PVA, and 50%PEO/505PVA). Samples miscibility ,and thermal stability were studied  by using differential scanning calorimetry(DSC),and thermo gravimetric analysis (TGA) analysis. The results proved that there was one glass transition temperature (Tg=160°C) at 25%PEO\PVA ratio
)that was attributed to its miscibility. This miscibility associated with (Hydrogen  bonds) between (Hydroxyl group) in PVA, and PEO, whereas there were two glass transition temperature for the blends ratio more than 30%PEO,that was due its immiscibility. The results proved increase in glass transition temperature (Tg) with PEO loading increase: whereas the melting point was fixed about(Tm=310°C). TGA results showed that  PEO loading caused overlapping between degradation stages ,and shifting in the second stage to higher degradation temperature, that was due to the good  PVA, and PEO compatibility, and thermal  stability improved of polymer blends. The mechanical properties of the samples  involved were studied :it was found  that  the tensile strength decreased with PEO ratio increase: whereas ,the elongation at break increased  with PEO ratio . 25% PEO/PVA proved  better tensile strength than the others blend ratios and elongation-at-break values in comparison with that ratio more than 25%,which was due  to good miscibility. These results were enhanced with optical microscope and FTIR analysis. 25%PEO/PVA was sellected to  study the UV-Weathering effect on the mechanical properties according to its ultimate strength(26.67MPa) in comparision with the blends envolved.The stress strain curves for 25%PEO/PVA before and after UV-Weathering with periods of time(25,60,and 90Hr.) showed little changes in ultimate strength up  to (60Hr) exposure time,then there were little decrese in ultmate strength in(90Hr) exposure time . Ultimate tensile strength decrease was attributed to premature failur induced by polymer photo degradation. UV-Weathering caused yelowish of  exposed samples that was due to long chain conjugated polymer sequencesbond formation induced by oxidative  photo degradation . The results proved little changes within (60Hr),that was attributed to polymer stability.It was folowed by little changes in tensile strength and   the elongation at break decreased that was due to sample brittlence increase,which was induced  by irradiation ,that caused modulus of elasticity increase. It was experimentally observed that the value of thermal conductivity of (PVA= 0.099W/cm.K).The results proved decrease in thermal conductivity with PEO loading increase.

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Publication Date
Sat Jul 06 2024
Journal Name
Multimedia Tools And Applications
Text classification based on optimization feature selection methods: a review and future directions
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A substantial portion of today’s multimedia data exists in the form of unstructured text. However, the unstructured nature of text poses a significant task in meeting users’ information requirements. Text classification (TC) has been extensively employed in text mining to facilitate multimedia data processing. However, accurately categorizing texts becomes challenging due to the increasing presence of non-informative features within the corpus. Several reviews on TC, encompassing various feature selection (FS) approaches to eliminate non-informative features, have been previously published. However, these reviews do not adequately cover the recently explored approaches to TC problem-solving utilizing FS, such as optimization techniques.

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Publication Date
Mon Nov 01 2021
Journal Name
Iop Conference Series: Earth And Environmental Science
Study of Seed Soaking and Foliar Application of Ascorbic Acid, Citric Acid and Humic Acid on Growth, Yield and Active Components In Maize
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Foliar application and seed soaking has been used as a means of supplying supplemental doses of nutrients, plant hormones, stimulants, and organic components. the effects of these applications have included yield increases, and improved drought tolerance, and enhanced crop quality, so A field experiment was carried out during spring seasons in 2019 and 2020 for styding Seed soaking and Foliar Application of Ascorbic acid, Citric acid and Humic acid on Growth, Yield and Active Components IN Maize. Randomized complete block design in split plots arrangement was used with three replicates. Main-plots were for seeds soaking with ascorbic, citric (100 mg l-1) frequently and humic at (1 ml l-1). Sub-plots were for vegetative parts nutrition with

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Publication Date
Wed Jul 29 2020
Journal Name
Iraqi Journal Of Science
Influence of Inclined MHD on Unsteady Flow of Generalized Maxwell Fluid with Fractional Derivative between Two Inclined Coaxial Cylinders through a Porous Medium
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"This paper presents a study of inclined magnetic field on the unsteady rotating flow of a generalized Maxwell fluid with fractional derivative between two inclined infinite circular cylinders through a porous medium. The analytic solutions for velocity field and shear stress are derived by using the Laplace transform and finite Hankel transform in terms of the generalized G functions. The effect of the physical parameters of the problem on the velocity field is discussed and illustrated graphically.

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Publication Date
Thu Dec 26 2024
Journal Name
Journal Of Baghdad College Of Dentistry
Immunohistochemical evaluation of vascular endothelial growth factor and transforming growth factor-beta on osseointegration of CpTi implant radiated by low level laser therapy
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Background: Dental implants provide a unique treatment modality for the replacement of lost dentition .This is accomplished by the insertion of relatively inert material (a biomaterial) into the soft and hard tissue of the jaws, there by providing support and retention for dental prostheses. Low level laser therapy (LLLT) is an effective tool used to prompt bone repair and modeling post surgery; this has referred to the biostimulation effect of LLLT. The aims of this study were to evaluate the immmunohistochemical expression of vascular endothelial growth factor (VEGF) and transforming growth factor -beta (TGF-β) in experimental and control groups with mechanical test. Materials and Methods: Thirty two adult New Zealand white rabbits use

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Publication Date
Thu Dec 26 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Implementation of Total Productive Maintenance (TPM) for industrial establishments and their impact on operational strategy: applied research in a sample of industrial companies
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The aim of the research is to measure the relationship and effect of the application of total production maintenance TPM in the operational strategy, as it is considered one of the most important strategies for the process of restoring production losses because of inefficient equipment. Competitive edge in the global market by upgrading the operational strategies of OS in the application of TPM in those institutions that apply both H-OS-oriented and P-OS-oriented strategies where the strategy has been identified as a critical success factor. The aim of this study is to attempt to consider the application of comprehensive productive maintenance in industrial establishments

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Publication Date
Tue Mar 01 2022
Journal Name
Academy Of Accounting And Financial Studies Journal
Impact of Digital Audit on Improving performance Quality and Reduce Costs An applied research in a sample of private auditing firms and offices
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Publication Date
Wed Jul 11 2018
Journal Name
دراسات تربوية
Understanding the nature of the scientific endeavor among chemistry teachers according to the Educational Reform Project 2061
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Publication Date
Thu Dec 26 2024
Journal Name
Journal Of Babylon Center For Humanities Studies
The reflection of the Arab character in Israeli children's literature in the years 1990 - 2015
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Publication Date
Mon May 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Sedimentary Structure and Determine the Diriction of the Old Current to the By Hassan Formation Northeast Iraq
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 This research deal the primary and secondary sedimentary structures in the By Hassan Formation in the three locations in the northeast of Iraq.          Can be recognize many geological structures such as cross bedding, planer bedding, graded bedding, channel structure and mud ball house deposit in the flood plain. The ether side this research study the direction of old current and sedimentary structure that made by the one direction current

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Publication Date
Thu Dec 26 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Role of the Financing Policy for Sustainable Social Development in Iraq for the Period (2014-2016)
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The development of a future mechanism for sustainable development in Iraq to meet the current and future challenges requires an analysis of the indicators of sustainable development. This research aims at presenting and analyzing the social care aspect and highlighting the important role of taxes with a focus on social sustainable development to determine the extent and direction of changes. Level of progress, the researcher concludes the weakness of the financial allocations to the Ministry of Labor and Social Affairs and in line with the large number of people who apply the conditions and controls, and recommends the researcher the necessity of participation of all segments of society between the public and private sector In terms of o

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