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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
Fri Jan 01 2021
Journal Name
Desalination And Water Treatment
Elucidation of the removal of trivalent and divalent heavy metal ions from aqueous solutions using hybrid-porous composite ion-exchangers by nonlinear regression
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Publication Date
Sun Apr 02 2017
Journal Name
Journal Of Educational And Psychological Researches
" أثر استراتيجية الجيجسو في تحصيل مادة الجغرافيا وعمليات العلم لدى طالبات المرحلة الاعدادية"
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The goal of current researcher to know the impact of strategic Jigsaw in the collection of hypertext and geographic operations of science students at the preparatory stage And that by checking the following 1.There is no difference statistically significant at the significance level 0.05 between the experimental group students who were studying strategy Jigsaw and between the control group students who studied in the usual way traditional degrees in the average achievement in the subject of geographical 2.There is no difference statistically significant at the significance level 0.05 between the experimental group students who were studying strategy Jigsaw and between the control group students who studied in the usual way traditional av

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Educational And Psychological Researches
أثر أنموذج أدي وشايرفي تحصيل طالبات الصف الخامس الادبي واتجاهاتهن نحو مادة التاريخ
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The Effect of the Addie and Shayer Model on the Achievement of Fifth Grade Students and their Attitudes towards History

  1. Ahmed Hashim Mohammed and Hadil Jassas Ali

University of Baghdad - College of Education for Women

[email protected]

Abstract

The current research aims to examine the effect of the Adi and Shayer model on the achievement of fifth-grade students and their attitudes toward history. To achieve the research objective, the researcher has adopted two null hypotheses. 1) there is no statistically significant difference at the level o

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Publication Date
Sun Sep 11 2022
Journal Name
جامعة بغداد/ كلية التربية للعلوم الصرفة - ابن الهيثم
التفكير التخيلي وعلاقته بالقراءة الستراتيجية والتحصيل في مادة الرياضيات لدى طلاب المرحلة الثانوية
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Publication Date
Sun Jun 30 2024
Journal Name
مجلة نسق
اثر استراتيجية هرم الافضلية في تحصيل مادة الكيمياء عند طلاب الصف الثاني المتوسط
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يهدف البحث الحالي التعرف على اسناتيجية هرم الافضلية في تحصيل طلاب الصف الثاني المتةسط لمادة الكيمياء ولتحقيق هدف البحث تم اتباع الننهج شبه التجريبي ذو الضبط الجزئي وتم تحديد مجتمع البحث بطلاب الصف الثاني في جميع المدارس المتوسطة والثانوية التابعة لمديرية تربية بابل قسم تربية المسيب

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Publication Date
Thu Mar 30 2023
Journal Name
مجلة نسق
اثر استراتيجية فجوة المعلومات في تصيل مادة الكيمياء عند طلاب الصف الثاني المتوسط
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ريل لسادة الكيسياء َ جؼ البحث الى التعخؼ عمى أثخ استخاتيجية فجػة السعمػمات في التح َى جؼ البحث فقج صيغت الفخضية التي َ تػسط , والتحقق مغ ى ُ جى شلاب الرف الثاني الس َ ل جؼ البحث أعتسج الباحث َ تتعمق بالتحريل ولتحقيق ى ػعتيغ متداويتيغ ُ بي لسجس ِ ي السشيج التجخ ريل الجراسي , تكػنت عيشة البحث مغ َ ) شالب مغ شلاب ٗٛ( ذواتي اختبار بعجي لمتح -ٕٕٕٓالرف الثاني الستػسط في ( متػسصة الذييج خزيخ جاسع العارضي ) لمعاـ الجارسي (

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Publication Date
Sun Jan 04 2015
Journal Name
Journal Of Educational And Psychological Researches
Effectiveness of the self-questioning strategy in the achievement of the third stage Institutes of teacher preparation and decision - making in Chemistry
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This research aims to find out "the effectiveness of the self-questioning strategy in the achievement of students Phase III institutes of teacher preparation and decision-making in chemistry." The researcher follows approach quasi-experimental with a post-test, and the sample consisted of (27) from " Teachers Training Institute-AL-Byaa "in Directorate of Education Baghdad Karkh / 2 students divided into two unequal groups: experimental its number (14) students studied using reciprocal teaching strategy and control its number (13) students have studied in the usual way.The two groups were equivalent extraneous variables.

The researcher was prepare achievement test consist of 40 items was the adoption of a measure of decision-makin

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Publication Date
Wed Dec 14 2016
Journal Name
Journal Of Baghdad College Of Dentistry
Comparative Evaluation of the Effect of Different Universal Adhesives and Bonding Techniques on the Marginal Gap of Class I Composite Restoration (A SEM Study)
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Background: With the increase in composite material use in posterior teeth, the concerns about the polymerization shrinkage has increased with the concerns about the formation of marginal gaps in the oral cavity environment. New generation of adhesives called universal adhesive have been introduced to the market in order to reduce the technique sensitive bonding procedures to give the advantage of using the bonding system in any etching protocol without compromising the bonding strength. The aim of the study was to study marginal adaptation of two universal adhesives (Single bondâ„¢ Universal and Prime and Bond elect) using 3 etching techniques under thermal cycling aging. Materials and Methods: Forty-eight sound maxillary first premola

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Publication Date
Tue Jan 02 2018
Journal Name
Journal Of Educational And Psychological Researches
The effect of Dunn Dunn model on students’ achievement in Geography course
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The study seeks to investigate the effect of Dunn Dunn learning style model on students’ achievement. Besides, the way of developing students’ deductive thinking by testing the null hypothesis: there is no significant difference between experimental group who takes Dunn Dunn model as style in studying geography and control group that follows a traditional method in studying geography at the level of (0,05). Additionally, there is no significant difference between experimental group who takes Dunn Dunn model as style in studying geography and control group that follows a traditional method in studying geography at the level of (0,05) on testing developing deductive thinking skills. The researcher adopted a quasi-experimental posttest

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Publication Date
Thu Jun 15 2017
Journal Name
Journal Of Baghdad College Of Dentistry
Fracture Resistance of Endodontically Treated Premolar Teeth with Extensive MOD Cavities Restored with Different Bulk Fill Composite Restorations (An In vitro Study)
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Background: The present in-vitro study was undertaken to evaluate and compare fracture resistance of weakened endodontically treated premolars with class II MOD cavities restored with different bulk fill composite restorations (EverX posterior, Alert, Tetric EvoCeram Bulk Fill, and SDR). The type and mode of fracture were also assessed for all the experimental groups. Materials and Method: Forty-eight human adult maxillary premolar teeth were selected for this study. Standardized extensive class II MOD cavities with endodontic treatment were prepared for all teeth, except those that were saved as intact control. The teeth were divided into six groups of eight teeth each (n=8): (Group 1) intact control group, (Group 2) unrestored teeth with

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