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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
Thu Mar 01 2018
Journal Name
Nauchforum
THE PROBLEM OF TRANSLATING METAPHOR IN AN ARTISTIC TEXT (ON THE MATERIAL OF RUSSIAN AND ARABIC LANGUAGES)
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THE PROBLEM OF TRANSLATING METAPHOR IN AN ARTISTIC TEXT (ON THE MATERIAL OF RUSSIAN AND ARABIC LANGUAGES)

Publication Date
Fri Jun 15 2018
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of phosphate ester addition on transverse strength and hardness of heat cured acrylic denture base material
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Background: acrylic resin denture base consider a common denture base material for its acceptable cost, aesthetic and easy processing but still has disadvantages including easy of fracture and low impact strength. Material and method: The experimental group was prepared by addition of 15% phosphoric acid 2-hydroxyethyl methacrylate ester (PA2HEME) with polymethyl methacrylate monomer; the experimental groups was compared with the control one. The specimens were prepared according to ADA specification No. 12 with dimension 65 mm x 10 mm x2.5 mm (length x width x thickness respectively). The prepared specimens were tested by three-point flexural strength utilizing Instron Universal Testing Machine (WDW, Layree Technology Co.), Shore D hard

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Publication Date
Fri Mar 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
Emotional Trends, and Emotional Exhaustion in organizations: (Developing foundations the philosophy and thinking in organizational behavior)
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Emotional exhaustion considered one of the critical factors in the formation and composition of organizational behavior of individuals within organizations, as well as social behavior and psychological, and emotional exhaustion is one of the three components of burnout, as well as depersonalization (cynicism) and low achievement, the emergence of research relevant to this concept began at the beginning of the seventies of the twentieth century, then started to become clear features in the eighties it. This research aims to build intellectual framework for draining emotional exhaustion through highlight on most important philosophical contents, as well as review and analysis of some models associated with this concept, and then a

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Publication Date
Tue May 02 2023
Journal Name
المؤتمر العلمي الدولي السادس للعلوم الانسانية والتربوية (مؤتمر ايجهار السادس) في جامعة اغادير الحكومية التركية واكاديمية
قواعد السلوك الاجتماعي في العهد الجديد بين التأويل والترجمة الحرفية في نصوص العهد القديم
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الملاخص

Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Educational And Psychological Researches
Teaching Competencies Required For Teachers of History in the Preparatory Stage
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         This study attempts to determine the necessary teaching competencies for teachers and the level of their importance in the development of their performance professionally and scientifically, and the progress towards a better future to achieve an effective level. Accordingly, the research community consists of the morning-preparatory schools for boys at the General Directorate of Education of Baghdad \ Rusafa2. The study sample included (68) teachers constituted 88.31% of the total community of teachers. As for the research tools, the researcher adopted the descriptive method by using the observation method in which the researcher prepared a list of teaching. For verifying the re

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Publication Date
Tue Jan 17 2012
Journal Name
Journal Of Electron Devices
INVESTIGATION OF OPTICAL PROPERTIES OF THE PbS/CdS THIN FILMS BY THERMAL EVAPORATION
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In this work, we have investigated optical properties of the thermally evaporation PbS/CdS thin films. The optical constant such as (refractive index n, dielectric constant εi,r and Extinction coefficient κ) of the deposition films were obtained from the analysis of the experimental recorded transmittance spectral data. The optical band gap of PbS/CdS films is calculate from (αhυ)1/2 vs. photon energy curve.

Publication Date
Sun Oct 01 2023
Journal Name
Solid State Communications
Influence of In-dopant on the optoelectronic properties of thermal evaporated CuAlTe2 films
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In the current study, CuAl0.7In0.3Te2 thin films with 400 nm thickness were deposited on glass substrates using thermal evaporation technique. The films were annealed at various annealing temperatures of (473,573,673 and 773) K. Furthermore, the films were characterized by X-ray Diffraction spectroscopy (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and Ultra violet-visible (UV–vis). XRD patterns confirm that the films exhibit chalcopyrite structure and the predominant diffraction peak is oriented at (112). The grain size and surface roughness of the annealed films have been reported. Optical properties for the synthesized films including, absorbance, transmittance, dielectric constant, and refr

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Publication Date
Sun Oct 01 2023
Journal Name
Solid State Communications
Influence of In-dopant on the optoelectronic properties of thermal evaporated CuAlTe2 films
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Publication Date
Thu Dec 31 2015
Journal Name
Al-khwarizmi Engineering Journal
Effect of Acetic Acid on Electrochemical Behavior of Sealed AA2319-T3 Al-Alloys Anodized in Phosphoric Acid Electrolytes
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Abstract

      The present study investigates the effect of acetic acid on corrosion behavior and its potential of hydrothermally sealed anodized AA2319-Al-alloys. Anodizing treatment was performed in stagnant phosphoric acid electrolyte with or without addition of acetic acid. Hydrothermal sealing was carried out in boiling water for each anodized specimen. The open circuit potential of the unsealed and sealed anodized samples was examined using open circuit potential measurement for the purpose of starting in scanning polarization diagrams. The potentiostatic polarization technique measurements were performed to assess corrosion behavior and sealing quality (i.e., degree of sealing) of

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Publication Date
Mon Jun 27 2022
Journal Name
Sustainability
Thermal Properties of Hydrated Lime-Modified Asphalt Concrete and Modelling Evaluation for Their Effect on the Constructed Pavements in Service
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Flexible pavements are subjected to three main distress types: fatigue crack, thermal crack, and permanent deformation. Under severe climate conditions, thermal cracking particularly contributes largely to a considerable scale of premature deterioration of pavement infrastructure worldwide. This challenge is especially relevant for Europe, as weather conditions vary significantly throughout the year. Hydrated lime (HL) has been recognized as an effective additive to improve the mechanical properties of asphalt concrete for pavement applications. Previous research has found that a replacement of conventional limestone dust filler using hydrated lime at 2.5% of the total weight of aggregates generated an optimum improvement in the mec

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