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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 Mar 15 2021
Journal Name
Energies
Intensifying the Charging Response of a Phase-Change Material with Twisted Fin Arrays in a Shell-And-Tube Storage System
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A twisted-fin array as an innovative structure for intensifying the charging response of a phase-change material (PCM) within a shell-and-tube storage system is introduced in this work. A three-dimensional model describing the thermal management with charging phase change process in PCM was developed and numerically analyzed by the enthalpy-porosity method using commercial CFD software. Efficacy of the proposed structure of fins for performing better heat communication between the active heating surface and the adjacent layers of PCM was verified via comparing with conventional longitudinal fins within the same design limitations of fin material and volume usage. Optimization of the fin geometric parameters including the pitch, numb

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Publication Date
Thu Nov 07 2024
Journal Name
Journal Of Thermal Analysis And Calorimetry
Performance improvement of phase change material (PCM)-based shell-and-tube-type latent heat energy storage system utilizing curved fins
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Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Caroll’s Pattern on the Second Intermediate Class Pupils' Achievement in Geography
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The present study aims at finding out the (effect of the Caroll’s pattern on the second intermediate class pupils' achievement in geography)

The partial experimental design of two groups, experimental and control, with pre-post tests is used. The sample is represented in (74) female pupils. The sample is divided into two groups (38) experimental group and (36) control one. The sample is selected from first intermediate  class pupils    ( Am Salama Secondary School for girls) \ Baghdad\ Al-karkh-1, for academic year 2015-2016.

The researcher has equalized the two groups in several variables: the previous achievement tests, intelligence, age in months, the scor

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Publication Date
Thu Dec 01 2022
Journal Name
Journal Of Engineering
The Effectiveness of a Simulation Model of Thermal Insulation in Building Materials Using Cellulose Extracted from Agricultural Waste in Baghdad
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This study found that one of the constructive, necessary, beneficial, most effective, and cost-effective ways to meet the great challenge of rising energy prices is to develop and improve energy quality and efficiency. The process of improving the quality of energy and its means has been carried out in many buildings and around the world. It was found that the thermal insulation process in buildings and educational facilities has become the primary tool for improving energy efficiency, enabling us to improve and develop the internal thermal environment quality processes recommended for users (student - teacher). An excellent and essential empirical study has been conducted to calculate the fundamental values ​​of the

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Publication Date
Sun Mar 15 2020
Journal Name
Journal Of The College Of Education For Women
Iraq The Impact of Lee’s Cognitive Strategy on the Achievement of the 5th Grade Literary brunch Female Students in the Module of History
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  The research aims to find out the impact of Lee’s cognitive strategy on the achievement of fifth-grade literary students in the module of history. The research community consists of the secondary female day schools of Al-Karkh Al-Oula Directorate General of Education. The size of the research sample comprises (45) female students of the fifth grade of the literary brunch, (21) students for the experimental group and (24) students for the control group. The researchers have chosen an experimental design with partial control to suit the current research and its goal. They used a unified tool to measure the achievement of female students, which consisted of (50) items characterized by sincerity and they extracted the stability of t

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Publication Date
Sun Apr 02 2017
Journal Name
Journal Of Educational And Psychological Researches
Impact beyond the knowledge when students of the Faculty of education in teaching methods
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Research aims to know the impact beyond the defined in the collection. The research community is the second school students at Baghdad University and a research sample (63) students, the number of experimental group (27) students and a control group (30) students.  The researcher was rewarded in variable lifetime for students and educational attainment and educational level of the parents and the educational level of mothers. The researcher has developed a test took the number of paragraphs (20).  A test was true after it has been submitted to the Group of arbitrators. The test was consistent with test method used and the reliability coefficient (0, 88). Either the statistical methods used by the researcher are: Pearson correla

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Publication Date
Tue Jan 01 2008
Journal Name
Journal Of Educational And Psychological Researches
مستويات التقويم والتصانيف التي تضمنتها في اسئلة امتحان مادة التاريخ
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      جاء التقويم  ليكون مكملا للعمليات التعليمية يساعد على الوقوف على نتائجها وسبل النهوض بها والوقوف على المعوقات التي تقف امام مسيرتها وقد عنيت عمليات التقويم باهتمام كبير من قبل القائمين على العمليات التعليمية اذ عقدت العديد من المؤتمرات والندوات واجريت العديد من الدراسات عالميا ومحليا من اجل الوقوف على هذه العملية المهمة الداعمة للتعليم والنهوض بمستويات المتعلمين ، ومن بي

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Publication Date
Fri Aug 31 2018
Journal Name
مجلة العلوم النغسية
أثر استراتيجية تعليمية في تحصيل مادة العلوم لطلاب الاول المتوسط
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ن الهدف من هذا البحث هو معرفة أثر إستراتيجية تعليمية في تحصيل مادة العلوم لدى طلاب الصف الاول المتوسط. ولتحقيق هدف البحث صاغ الباحثان الفرضية الآتية: لا توجد فروق ذو دلالة إحصائية عند مستوى (0,05) بين متوسط درجات طلاب المجموعة التجريبية الذين يدرسون مادة العلوم وفق إستراتيجية تعليمية وبين متوسط درجات طلاب المجموعة الضابطة الذين يدرسون المادة نفسها بالطريقة التقليدية في اختبار التحصيل. بلغت عينة البحث (59) طالبا

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Publication Date
Sun Jan 01 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Science
Fabrication and Characterization CdO: In/Si Photovoltaic Solar Cell Prepard By Thermal Evaporation
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Publication Date
Tue Aug 22 2017
Journal Name
Heat Transfer—asian Research
Thermal Enhancement from Pin Fins by Using Elliptical Perforations with Different Inclination Angles
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Abstract<p>Many of the proposed methods introduce the perforated fin with the straight direction to improve the thermal performance of the heat sink. The innovative form of the perforated fin (with inclination angles) was considered. Present rectangular pin fins consist of elliptical perforations with two models and two cases. The signum function is used for modeling the opposite and the mutable approach of the heat transfer area. To find the general solution, the degenerate hypergeometric equation was used as a new derivative method and then solved by Kummer's series. Two validation methods (previous work and Ansys 16.0‐Steady State Thermal) are considered. The strong agreement of the validation results (0.3</p> ... Show More
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