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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
Journal Of Engineering
Analysis of Double Skin Composite Slabs
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This paper deals with finite element modeling of the ultimate load behavior of double skin composite (DSC) slabs. In a DSC slab, shear connectors in the form of nut bolt technique studs are used to transfer shear between the outer skin made of steel plates and the concrete core. The current study is based on finite element analysis using ANSYS Version 11 APDL release computer program. Experimental programmes were carried out by the others, two simply supported DSC beams were tested until failure under a concentrated load applied at the center. These test specimens were analyzed by the finite element method and the analyses have shown that these slabs displayed a high degree of flexural characteristics, ultimate strength,

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Publication Date
Wed Aug 15 2018
Journal Name
Al-khwarizmi Engineering Journal
Study the Dissociation Enthalpies for R134a Clathrate Hydrate in Binary and Ternary Systems
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In the present work the clathrate hydrate dissociation enthalpies of refrigerant R134a+ water system, and R134a + water + salt system were determined. The heat of dissociation of three types of aqueous salts solutions of NaCl, KBr and NaF at three concentrations (0.09, 0.17and 0.26) mol·kg−1 for each salt type, were enthalpy measured. The Clapeyron equation was used tocalculate heat of dissociation of experimental data for binary and ternary system.In order to find the effect of compressibility factor on heat dissociation enthalpy, the study was conducted by using equation of state proposed by Peng and Robinson Stryjek-Vera (PRSV). The obtained results of dissociation enthalpy for binary system were (143.8) kJ.mol-1

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Publication Date
Wed Oct 24 2018
Journal Name
European Journal Of Environmental And Civil Engineering
Investigation the impacts of fuel oil contamination on the behaviour of passive piles group in clayey soils
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Publication Date
Mon Sep 01 2014
Journal Name
Al-khwarizmi Engineering Journal
Numerical Investigation of Transient Heat Conduction through a Thermal Insulation of Temperature Dependant Thermal Properties
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The two-dimensional transient heat conduction through a thermal insulation of temperature dependent thermal properties is investigated numerically using the FVM. It is assumed that this insulating material is initially at a uniform temperature. Then, it is suddenly subjected at its inner surface with a step change in temperature and subjected at its outer surface with a natural convection boundary condition associated with a periodic change in ambient temperature and heat flux of solar radiation. Two thermal insulation materials were selected. The fully implicit time scheme is selected to represent the time discretization. The arithmetic mean thermal conductivity is chosen to be the value of the approximated thermal conductivity at the i

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Publication Date
Fri Dec 31 2021
Journal Name
Political Sciences Journal
Moderation in Omani External political behavior (1970-2020)
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Receipt date:08/26/2020 accepted date:9/8/2020 Publication date:12/31/2021

Creative Commons License This work is licensed under a Creative Commons Attribution 4.0 International License.

        The research entitled (Moderation in Omani External Political Behavior 1970-2020. contained introduction and two sections conclusion and recommendations. The introduction included a general overview of the topic, and the importance of the political behavior o

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Publication Date
Tue Jan 01 2008
Journal Name
Journal Of Educational And Psychological Researches
اثرالتعلم باللعب في السلوك العدواني لدى اطفال الروضه
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يستهدف البحث التعرف على اهمية التعلم باللعب لاطفال رياض الاطفال وانعكاساتها على تعديل سلوكهم، حيث ان اللعب هو دنيا الطفل المليئة بالمتعة والاستطلاع والاستكشاف، كما ان اللعب بالنسبة للاطفال يمثل لهم الحياة بكل ما فيها من معنى.

وفي الوقت نفسه اللعب هو وسيلة من وسائل الضبط والتوجيه للتعامل مع سلوك الاطفال، فمن خلال اللعب نستكشف النبوغ والتفوق منذ وقت مبكر، حيث ان التعلم باللعب يمثل حاجة حيو

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Publication Date
Sun Apr 07 2013
Journal Name
Journal Of Educational And Psychological Researches
Psychophysiological Control in Behavior
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         The Feedback Concept has been spread as an organized trend for scientific research since it has a significant importance for human behavior and how it has been directed and controlled by the individual, feedback has numerous definitions but the simplest definition is; feedback is the information received by the individual from the output of his behavior, In addition to the mutual relationship between the individual and the stimulation that provide him with the basic information by the biological control of his behavior, Since feedback cannot be accomplished without receiving information from the inner and outer environment, the biological and physiological information become the ma

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Publication Date
Mon Oct 06 2014
Journal Name
Journal Of Educational And Psychological Researches
Impulsive behavior among Kindergarten children and its relation ship with some variables preparation
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Quite anumber of parents and educators of this behavior,which is characterized by exaggerating locomotor activity and impulsivity and recklessness and the difficulty of continuing the status of certain bodily more than one minute ,and the difficulty of waiting to meet aparticular need or desire,it also characterized by thos meddling children the affairs of others and increased their  chatter does not seem the case when you listen to talk to them and they characterized by  weak self-confidence and are more solid and seem un able to keep ther responses because of the severity of anxiety .The research aims to know impulsive behavior among kindergartens children and its relation ship with some variables, and the sa

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Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
Role socialization family erroneous and its impact on criminal behavior
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The correct and sincere process of socialization is working on appropriate social climate in
which this process is the provision, and the climate is achieved in the presence of a positive
environment free of negatives and contradictions, but when there is a socialization processes
inadequate and contradictory was not based on the principles of punishment and reward nor a
balance between methods soft and intensity of treatment and interaction with small and
adolescent does not require intensive social care formulas do not create the conditions
essential items required by the successful and effective socialization, the young and the young
people who are going through in such Altanisah and educational operations will be

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Publication Date
Sat Oct 23 2021
Journal Name
Iraqi Journal Of Physics
Thin Film Dye Laser Based on BBQ Doped Poly (Methyl Meth-Acrylate)
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This paper reports on the laser emission properties of the BBQ dye in poly (methyl meth-acrylate)(PMMA). This host material combines the advantages of an organic environment for dye with the thermoptical mechanical properties of an organic dye. A BBQ dye solid solution in PMMA polymer. A nitrogen laser in untuned laser cavity has pumped thin films. We developed the concentration and the thickness to get high efficiency. The laser efficiency had been increased from 7% at thickness 1.5 m to 16.5% at thickness 3.5m, and from 1% to 10% when concentration increased from 1x10-5M to 1x10-3 M

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