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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
Journal Of Mechanical Engineering Research And Developments
Numerical investigation for Natural Convection in a square Enclosure with partially active thermal sides' wall
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Three-dimensional cavity was investigated numerical in the current study filled with porous medium from a saturated fluid. The problem configuration consists of two insulated bottom and right wall and left vertical wall maintained at constant temperatures at variable locations, using two discretized heaters. The porous cavity fluid motion was represented by the momentum equation generalized model. The present investigation thermophysical parameters included the local thermal equilibrium condition. The isotherms and streamlines was used to examine energy transport and momentum. The meaning of changing parameters on the established average Nusselt number, temperature and velocity distribution are highlighted and discussed.

Scopus
Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Energy Storage
Multiple-segment metal foam application in the shell-and-tube PCM thermal energy storage system
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Publication Date
Sun Dec 16 2018
Journal Name
Al-academy
An Educational Model in Journalistic Production Course to Develop the Creative Thinking Skills of Printing Design Students
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The printing designer's creative thinking is a deliberate  mental process based on specific skills that stimulate the motivation of  the student to learn and call for  new information for the investigation and research to discover the problems and attitudes and through reformulating the experience in new patterns depending on the active imagination and the flexible scientific thinking through providing the largest number possible  of various unfamiliar  printing design models, and testing their suitability and then readjusting the results with the availability of  suitable educational, learning and academic atmosphere.

The designer's creative thinking depends on main skills. Fluency skill is to put t

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Publication Date
Wed Jun 14 2023
Journal Name
Al-academy
The effect of dramatizing characters within the social subject of the basic education stage on student achievement
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The researcher used the experimental approach due to its suitability and the nature of the research problem. The research community was represented by the eighth-grade students in the Rozak Elementary Mixed School affiliated with the General Directorate of Education in Erbil / the center, for the academic year (2021-2022), the number is (96) students, and the research sample consisted of (63) male and female students, with (31) in the experimental group, and (32) in the control group, and (11) students were excluded by (5) students from the experimental group, and (6) students from the control group, as the excluded, are students who failed and were absent from the lessons, and accordingly, the research sample became composed of (52) mal

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Publication Date
Sat Feb 09 2019
Journal Name
Journal Of The College Of Education For Women
Health Situations Teaching Of Biology The Manner Teaching Its Relation To Ability Mind and Students Technical Medical Institute
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The Present study aims at answering the following questions:
1-What is the level of the teaching style of biology teachers who teach (human and his
health)

2-what is the level of healthy attitude to the teachers of biology who teach (human and his
health).
3- is there any relation between the teaching style of biology teachers who teach (human and
his health)and their student's Ability Mind.
4- is the any relation between the level of the healthy attitude to the teachers of biology who
teach (human and his health).
The researcher made the following for the purpose of answering the question of the study:
1-The card of observing the level of the teaching style (lecture style )to the teachers of
biology

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Publication Date
Sun Jul 01 2018
Journal Name
Journal Of Educational And Psychological Researches
The effect of constructivist model of yager in acquiring the geographical concepts among first intermediate students in geography
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The purpose of the study is to investigate the effect of the constructivist model of yager in acquiring the geographical concepts among first intermediate students in geography. The study was carried on based on the null hypothesis, which states, there is no significant difference at the level of (0.05) between the experimental group that follows yager model in learning the principles of geography, and the control group that studies the same subject considering the traditional methods of learning, the. To do so, a sample of (70) first-intermediate student were chosen purposefully from two random class for the academic year (2016-2017) divided into two groups. The selected schools located at Al-rusafa side in the city of Baghdad, as well

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Publication Date
Mon Jan 02 2017
Journal Name
Journal Of Educational And Psychological Researches
The impact of teaching with analogies in collection of chemistry students grade average and their attitudes towards article
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this research aims to identify the impact of teaching with ana logies in collection of chemistry students grade average.And direction in order to verify to the zero hypothesis has been formulated and validated,The researcher conducted experiment lasted a full semester as experimental design was chosen (exactly)two equal one pilot and another officer.The research community has been  selected one of intentional Middle School of the Education Directorate in B aghdad Karkh second either search sample consisted of (68) students from second grade average (34 ) Students for each group randomly selected research groups was equal to the following variables (lifetime months,parent of first grade chemistry degrees average test informat

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Publication Date
Wed Mar 29 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Electrosorption of Hexavalent Chromium Ions by MnO2/Carbon Fiber Composite Electrode: Analysis and Optimization of the Process by Box-Behnken Design
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A nano manganese dioxide (MnO2) was electrodeposited galvanostatically onto a carbon fiber (CF) surface using the simple method of anodic electrodeposition. The composite electrode was characterized by field emission scanning electron microscopy (FESEM), and X-ray diffraction (XRD). Very few studies investigated the efficiency of this electrode for heavy metals removal, especially chromium. The electrosorption properties of the nano MnO2/CF electrode were examined by removing Cr(VI) ions from aqueous solutions. NaCl concentration, pH, and cell voltage were studied and optimized using the Box-Behnken design (BDD) to investigate their effects and interactions on the electrosorption process. The results showed that the

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Publication Date
Fri Jun 27 2025
Journal Name
Journal Of Baghdad College Of Dentistry
The effect of different finishing and polishing systems on surface roughness of new low polymerized composite materials (An in vitro study)
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Background: Prophylaxis methods are used to mechanically remove plaque and stain from tooth surfaces; such methods give rise to loss of superficial structure and roughen the surface of composites as a result of their abrasive action. This study was done to assess the effect of three polishing systems on surface texture of new anterior composites after storage in artificial saliva. Materials and methods: A total of 40 Giomer and Tetric®N-Ceram composite discs of 12 mm internal diameter and 3mm height were prepared using a specially designed cylindrical mold and were stored in artificial saliva for one month and then samples were divided into four groups according to surface treatment: Group A (control group):10 specimens received no surfa

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Publication Date
Mon Jan 01 2024
Journal Name
Journal Of Photochemistry And Photobiology A: Chemistry
Synthesis of heterostructure composite (g-C3N4/phosphomolybdic acid) for synergistic piezo/photo-catalytic degradation of CR dye and S. aureus bacteria
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