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Thermal Behaviour of Paraffin Wax/Poly Vinyl Alcohol Composite Material
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Polymer additives binder system provides many properties useful in thermal energy storage (TES) then developed the efficient energy storage materials and green strength bodies system.

This paper studies the thermal energy storage property for polyvinyl alcohol (PVOH) / paraffin wax (WPw) blends. To enhance paraffin wax thermal conductivity, PVOH as a material which high conductivity was employed. A fixed weight of Paraffin wax was dispersed with PVOH heterogeneously at different additive weights ratios of PVOH/Pw (50/50, 67/33, 75/25, and 80/20) wt. ratio respectively. The composite material was prepared using wetted pressing method.

Both base materials (polyvinyl alcohol and paraffin wax) were scanned using differential scanning calorimeter (DSC) under non-isothermal conditions, the result was analysed to determine the thermal transition temperature of PVOH and paraffin wax base material. The thermal decomposition of PVOH and waste paraffin wax proved that high transition temperature (TG) for PVOH reached 209ᴼc rather than wax of 60ᴼc respectively. This result shows that PVOH suppress the thermal stability of PVOH/waste paraffin wax composites. Afterward examines the thermal conductivity enhancement using Lee- disk techniques. Composite materials PVOH/paraffin wax have a high thermal conductivity which increases thermal conductivity of waste paraffin wax as a heat storage media and  this allows to apply change in phase with wide range of temperatures, and the highest decreased ratio of phase-change heat is very low, compared to that of paraffin only. Therefore, PVOH, added to paraffin which has significant potential for enhancing the thermal storage characteristics of paraffin.

A wax/PVOH system acts as strength body resistance to sever contact of both air and moisture then a moisture absorbance percent was achieved by use both Fourier transform infrared spectroscopy (FTIR) techniques and moisture solutions (100% H2O) for all pure and composite material system Pw/PVOH, the results shows high resistance to ambient conditions (air/ moisture) for composite system rather than pure materials (PVOH and Pw). 

                                              

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Publication Date
Mon Apr 04 2022
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Baska Style in Achievement and Creative Thinking among Students in the Fifth Grade Literary Material and Application Rhetoric
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The current research aims to identify the effect of Baska style on students’ achievement and the creative thinking in material rhetoric and the application of students for fifth grade literary. To achieve the study objectives, the researcher has designed an achievement test to measure group of students in the fifth grade literary in material application. The researcher chose a sample of 40 female students from Khansa School for Girls in Baghdad for the academic year (2014 - 2015), he applied the test on an exploratory sample consisted of 30 female students from the research community. The study resulted in being no statistically significant difference at the level of significance (0.05) between the mean scores of the experimental group

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Publication Date
Sat Jun 07 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Early and delayed effect of 2% chlorhexidine on the shear bond strength of composite restorative material to dentin using a total etch adhesive
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Background: Lack of durability of the bond of the dental adhesive systems to tooth structure is one of the most important problems in tooth colored restorative work. This in vitro study was performed to evaluate the effect of 2% chlorhexidine gluconate(CHX) on dentin bond strength by using total etch adhesive system at twenty-four hours and three months of water storage. Material and methods:A flat dentin surface was prepared for forty sound human maxillary premolar teeth which were acid etched with 36% phosphoric acid gel after being divided randomly into four groups of ten teeth each according to storage time and CHX application, theCHX was applied for 60 seconds before adhesive application for groups I and III which were tested after twe

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Publication Date
Fri Feb 08 2019
Journal Name
Iraqi Journal Of Laser
Nano Fluid Detection for HPHE System Using Different Lasers
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Among the different passive techniques heat pipe heat exchanger (HPHE) seems to be the most effective one for energy saving in heating ventilation and air conditioning system (HVAC). The applications for nanofluids with high conductivity are favorable to increase the thermal performance in HPHE. Even though the nanofluid has the higher heat conduction coefficient that dispels more heat theoretically but the higher concentration will make clustering .Clustering is a problem that must be solved before nanofluids can be considered for long-term practical uses. Results showed that the maximum value of relative power is 0.13 mW at nanofluid compared with other concentrations due to the low density of nanofluid at this concentration. For highe

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Publication Date
Mon Oct 01 2007
Journal Name
Journal Of Educational And Psychological Researches
تطور مظاهر السلوك العدواني عند الاطفال من وجهة نظر معلميهم
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أهمية البحث والحاجة اليه :

الحمد لله رب العالمين القائل (( وانك لعلى خلق عظيم )) (سورة القام :4)  وصلى الله وسلم وبارك على نبينا محمد القائل " انما بعثت لأتمم مكارم الاخلاق " مسند احم: رقم الحديث 8595.

ان الاهتمام بالمشكلات السلوكية من اهم ركائن التربية والتعليم وتأتي تأتي اهميتها من ان التعيم يعين التغيير في سلوك الفرد نحو الافضل تحت تأثير الظروف والخبرات والمعارف والمهارات ال

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Publication Date
Sun Jan 01 2017
Journal Name
Journal Of Petroleum Science And Engineering
Nanoparticles influence on wetting behaviour of fractured limestone formation
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Nanoparticles have gained considerable interest in recent times for oil recovery purposes owing to significant capabilities in wettability alteration of reservoir rocks. Wettability is a key factor controlling displacement efficiency and ultimate recovery of oil. The present study investigates the influence of zirconium (IV) oxide (ZrO2) and nickel (II) oxide (NiO) nanoparticles on the wetting preference of fractured (oil-wet) limestone formations. Wettability was assessed through SEM, AFM and contact angle. The potentials of the nanoparticles to alter oil-wet calcite substrates water wet, was experimentally tested at low nanoparticle concentrations (0.004–0.05 wt%). Quite similar behaviour was observed for both nanoparticles at the same

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Synthesis and characterization of some modified polyvinyl alcohol
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Some esters were prepared from reaction of different molecular weight of PVA with some acid chloride (prepared by reaction of acid with thionyl chloride or phosphorous pentachloride)in the presence of pyridine. The thermal and reological properties were studied. The increasing Of bulky groups decreasing stability of the thermal and reological properties.

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Publication Date
Sat Jul 01 2023
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
A proposed audit program for a comprehensive electronic banking system based on business risks : applied research
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The research seeks to identify the comprehensive electronic banking system and the role of the auditor in light of the customer's application of electronic systems that depend on the Internet in providing its services, as a proposed audit program has been prepared in accordance with international auditing controls and standards based on the study of the customer's environment and the analysis of external and internal risks in the light of financial and non-financial indicators, the research reached a set of conclusions, most notably, increasing the dependence of banks on the comprehensive banking system for its ability to provide new and diverse banking services, The researcher suggested several recommendations, the most important of whi

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Publication Date
Mon Oct 01 2018
Journal Name
Iraqi Journal Of Physics
The study of thermal description for non-thermal plasma needle system
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Cold plasma is a relatively low temperature gas, so this feature enables us to use cold plasma to treat thermally sensitive materials including polymers and biologic tissues. In this research, the non-thermal plasma system is designed with diameter (3 mm, 10 mm) Argon at atmospheric pressure as well as to be suitable for use in medical and biotechnological applications.
The thermal description of this system was studied and we observed the effect of the diameter of the plasma needle on the plasma, when the plasma needle slot is increased the plasma temperature decrease, as well as the effect of the voltages applied to the temperature of the plasma, where the temperature increasing with increasing the applied voltage . Results showed t

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Publication Date
Sun Mar 02 2014
Journal Name
Baghdad Science Journal
Copolymerazaion of N-vinyl-2-pyrrolidon with Acrylic Acid and Methylmethacrylate
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Low conversion copolymerization of N-vinyl-2-pyrrolidon M.W = (111.14) VP (monomer-1) has been conducted with acrylic acid AA and methymethacrylate MMA in ethanol at 70ºC , using Benzoyl peroxide BPO as initiator . The copolymer composition has been determined by elemental analysis. The monomer reactivity ratios have been calculated by the Kelen-Tudos and Finman-Ross graphical procedures . The derived reactivity ratios (r1 , r2 ) are : (0.51 , 4.85) for (VP / AA ) systems and (0.34 , 7.58) for (VP , MMA) systems , and found the reactivity ratios of the monomer AA , MMA is mor than the monomer VP in the copolymerization of (VP / AA) and (VP /MMA) systems respectly . The reactivity ratios values were used for microstructures calculation.

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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Dynamic Analysis of Thin Composite Cylindrical and Spherical Shells
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In this work, an investigation for the dynamic analysis of thin composite cylindrical and spherical shells is presented. The analytical solution is based upon the higher order shear deformation theory of elastic shells from which the developed equations are derived to deal with orthotropic layers. This will cover the determination of the fundamental natural frequencies and mode shapes for simply supported composites cylindrical and spherical shells.

      The analytical results obtained by using the derived equations were confirmed by the finite element technique using the well known Ansys package. The results have shown a good agreement with a maximum percentage of discrepancy, which gives a confidence o

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