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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
Sat Aug 23 2025
Journal Name
Journal Of Baghdad College Of Dentistry
The effect of plasma treatment on shear bond strength of soft denture liner with two different types of denture base material (heat cure and light cure)
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Background: In this study we evaluate the effect of plasma treatment (oxygen and argon) gas in two different exposure times on the surface of heat cure and light cure acrylic resin. Materials and method: 100 specimens of heat cure and light cure acrylic resin were fabricated. The measurements of the samples were (75mm, 25mm and 4.5mm) length, width and depth respectively with stopper of 3mm depth. Two types of gas used oxygen and argon in (5,10) min by using (DC-glow discharge plasma device) then we apply cold cure soft lining material, with the help of Instron machine we test the shear stress value. Results: A highly significant effect after argon and oxygen gases treatment in both 5 and 10 min exposure times on shear bond strength to soft

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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Educational And Psychological Researches
Teaching methods approved in the university and its relationship to classroom discipline and management proposals treated
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The study aims detection teaching modalities adopted relationship in Jerash University exactly the classroom, and to achieve the goal of the study was to develop a questionnaire consisting of (39) items, and was achieving validity and reliability have, then sent to a sample of professors made up the university from (122) university professor of the total (172) professor, and they study population.

     Study found a relationship between the teaching methods of the four their strategies with classroom management, and as a result the overall average level, while Hspt critical thinking at the highest correlation with classroom discipline management relationship strategy, while the relatio

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Publication Date
Thu Feb 24 2022
Journal Name
Journal Of Educational And Psychological Researches
The Teaching Methods Used Calendar When Arabic Language Teachers in Middle
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This research aims to evaluate the teaching methods used by intermediate Arabic language teachers. To achieve the goal, the researcher followed the descriptive-analytical approach. The research sample was limited to Arabic language teachers at intermediate school for the academic year (2017-2018) the researcher chose a random sample included (155) teachers which form a (40%) Of the original community at Baghdad/ Rusafa1th. The researcher has developed standards of teaching methods which are (7) standards with (39) paragraphs included three alternatives. The results showed the need to pay attention to the use of various modern teaching methods. Moreover, the researcher suggested making an evaluation of the teaching methods used by Arabic

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Publication Date
Wed Sep 25 2019
Journal Name
Journal Of The College Of Education For Women
أثر انموذج بوسنر في تحصيل مادة الرياضيات لدى طلاب الصف الثاني المتوسط
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     يهدف البحث الحالي الى معرفة أثر انموذج بوسنرفي تحصيل مادة الرياضيات لدى طلاب الصف الثاني المتوسط .

ولتحقيق هدف البحث صاغت الباحثة الفرضية الآتية :

      لا يوجد فرق ذو دلالة إحصائية عند مستوى (0,05) بين متوسط درجات طلاب المجموعة التجريبية الذين درسوا مادة الرياضيات  وفق انموذج بوسنر، وبين متوسط درجات طلاب المجموعة الضابطة الذين درسوا المادة نفسها بالطريقة الاعتيادية في اخت

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Publication Date
Fri Jun 30 2023
Journal Name
مجلة نسق
اثر استراتيجية القوائم المركزة في تحصيل مادة الكيمياء طلاب الصف الثاني المتوسط
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يهدف البحث التعرف على اثر استراتيجية القوائم المركزة في تحصيل مادة الكيمياء عند طلاب الصف الثاني المتوسط وتم استخدام المنهد التجريبي ذو الضبط الجزئي وكذلك تم اختيار مجامع البحث جميع طلاب المدارس الثانوية والمتوسطة التابعة لمديرية تربية كربلاء

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Publication Date
Sat Jan 01 2011
Journal Name
مجلة كليه التربيه الاساسيه
تقويم محتوى كتاب مادة الكيمياء للصف الأول المتوسط على وفق معايير محددة
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يعد التقويم مبدأ مهماً في العملية التعليمية لأنه يساعد في التعرف على الاختلاف بين ما ينبغي تحقيقة وما تحقق فعلاً وما يترتب على ذلك من توصيات لدعم ما تحقق فعلاً (الأهداف التربوية) وتصحيح مسار العملية التعليمية من خلال المقترحات لتلافي السلبيات التي عثرت تحقيق الأهداف الأخرى وبما أن المحتوى هو أحد عناصر المنهج المهمة وهو وسيلة المعلم في أيصال المعلومات وبقائها في ذهن المتعلم أطول فترة ممكنه من خلال تبسيط المفا

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Publication Date
Tue Mar 01 2011
Journal Name
مجله ديالى للبحوث الانسانية
تقويم محتوى كتاب مادة الكيمياء للصف الخامس العلمي على وفق معايير محددة
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ان للمنهج المدرسي أهمية كبيرة جداً في العملية التربوية لأنه أداتها في تحقيق الأهداف التربوية المنشودة والتي تعمل على تقدم المجتمع وتطوره في مختلف الجوانب. بمعنى ان المنهج غير ثابت بل متغير ليواكب التطور والتغير الحاصل في العالم والمجتمع وهذا يعني ان المنهج المدرسي بكل عناصره والتي من ضمنها المحتوى في تطور دائم فما يصلح لفترة زمنية معينة لا يصلح لفترة زمنية قادمة مما يستلزم القيام بعملية تقويمية بشكل مستمر و

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Publication Date
Mon Jan 01 2007
Journal Name
Journal Of Educational And Psychological Researches
أثر أنموذج لاندا في تحصيل طالبات الصف الخامس العلمي في مادة الاحياء
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اظهرت نتائج ابحاث تربوية اجريت في الولايات المتحدة الامريكية ان تدريس مادة الاحياء يعتمد على حفظ المصطلحات والمفاهيم العلمية دون فهم واستيعاب لها، كما ان الاساليب والطرائق التدريسية المتبعة تقليدية وتؤكد على الجوانب الشكلية والنظرية والحفظ والتلقين. (عايش،1999،ص8).

        واشارت دراسة في وزارة التربية العراقية ان مادة الاحياء تشارك بعض المواد الاخرى في صعوبتها في المرحلة

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Publication Date
Fri May 10 2019
Journal Name
Research Journal Of Chemistry And Environment
Solid Phase Extraction of Theophylline in Aqueous Solutions by Modified Magnetic Iron Oxide Nanoparticles as an Extractor Material and Spectrophotometry Technique for the Determination
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new, simple and fast solid-phase extraction method for separation and preconcentration of trace theophylline in aqueous solutions was developed using magnetite nanoparticles (MIONPs) coated with aluminium oxide (AMIONPs) and modified with palmitate (P) as an extractor (P@AMIONPs). It has shown that the developed method has a fast absorbent rate of the theophylline at room temperature. The parameters that affect the absorbent of theophylline in the aqueous solutions have been investigated such as the amount of magnetite nanoparticle, pH, standing time and the volume, concentration of desorption solution. The linear range, limit of quantification (LOQ) and limit of detection (LOD) for the determination of theophylline were 0.05-2.450 μg mL-

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Publication Date
Fri Sep 30 2011
Journal Name
Al-khwarizmi Engineering Journal
Effect of Solid Loading on Carbon Dioxide Absorption in Bubble Column
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In the present work experiments were conducted to study  the effect of solid loading (1,5 and 9 vol.%) on the enhancement of carbon dioxide absorption in bubble column at various volumetric gas flow rate (0.75, 1 and 1.5 m3/h) and absorbent concentration (caustic soda)( 0.1,0.5 and 1 M  ). Activated carbon and alumina oxide (Al2O3) are used as solid particles. The Danckwerts method was used to calculate interfacial area and individual mass transfer coefficients during absorption of carbon dioxide in a bubble column. The results show that the absorption rate was increased with increasing volumetric gas flow rate, caustic soda concentration and solid loading. Mass transfer coefficient and interfac

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