تصنيع الطابوق الحراري الثقيل من خامات محلية
ملخّص البحث
لقد كان هذا البحث نتاج صراع واقع، وادعاء طرأ على ساحة الأمة اليوم ، وكان نصيبي هو الدفاع عن الدين بالقلم سلاح الفكر مما يراد من تشويه الحقائق او سرقة الدين بإسم الدين واحتكاره، لذا اردت عرض الموضوع كما عرضه القرآن في سورة البقرة بعد جهد تأمل ولجوء الى الله بأن يفيض علينا من سحائب رحمته وفضله ومَنهِ وكرمه بما يفتح لنا من فهم آياته في هذه السورة في س
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This study investigates the mechanical compression properties of tin-lead and lead-free alloy spherical balls, using more than 500 samples to identify statistical variability in the properties in each alloy. Isothermal aging was done to study and compare the aging effect on the microstructure and properties.
The results showed significant elastic and plastic anisotropy of tin phase in lead-free tin based solder and that was compared with simulation using a Crystal Plasticity Finite Element (CPEF) method that has the anisotropy of Sn installed. The results and experiments were in good agreement, indicating the range of values expected with anisotropic properties.
Keywords<
... Show MoreIn this study, the zinc oxide NPs have been synthesized from the fresh pomegranate peels extract using the precipitation method. The ZnO nanoparticles were produced from the reaction of fresh peels extract with zinc acetate salt which was used as zinc source in the presence of 2 M NaOH. The green synthesized nanoparticles were characterized through X-ray diffraction (XRD), UV-Vis diffuse reflection spectroscopy, Fourier transform infrared spectroscopy (FTIR), and Atomic force microscopy (AFM). The XRD patterns confirm the formation of hexagonal wurtzite phase structure for ZnO synthesized using pomegranate peels extract with average crystalline size of 28 nm. FTIR spectra identify the presence of many active functional groups for the pom
... Show MoreCurrent research included preparation, characterization of some new chitosan- hydroxy benzaldehyde-Schiff bases with maleic anhydride. The present study aimed to the synthesis and characterization of novel chitosan Schiff base compounds using para- hydroxy benzaldeh and maleic anhydride. The derivative of the schiff-chitosan base, which is associated with different drugs, has been replaced with different amino and hydroxy drugs. The derivative is characterized by different analytical techniques. The results of FT-IR studies clearly indicate construction of the chief amine group in chitosan and the emergence of new bands that correspond to the association of maleic anhydride with the chitosan base. TGA, 1
... Show MoreAn experimental study is carried out on the effect of vortex generators (Circular and square) on the flow and heat transfer at variable locations at (X = 0.5, 1.5, 2.5 cm) ahead of a heat exchanger with Reynolds number ranging from 62000< Re < 125000 and heat flux from 3000 ≤ q ≤ 8000 W/m2 .
In the experimental investigation, an apparatus is set up to measure the velocity and temperatures around the heat exchanger.
The results show that there is an effect for using vortex generators on heat transfer. Also, heat transfer depends on the shape and location. The circular is found t
... Show MoreIn the present work, the behavior of thick-walled cylinder of elasto-plastic material (polymeric material) has been studied analytically. The study is based on modified Von-Mises yield criterion (for non metallic material). The equations of stress distribution are obtained for the cylinder under general cases of elastic expansion, plastic initiation and elastic-plastic expansion.
A computer program is developed for evaluating the stress distribution. The solution is carried out for worst boundary conditions when the cylinder is subjected to the combination of pressure load, inertia load, and temperature gradient.
The results are presente
... Show Moreتكمن اهمية البحث في التعرف على مستوى التنوع الثقافي التي يتمتع بها مدراء المدارس الثانوية واهميته بالنسبة لمدرسي التربية الرياضية ودورهم الفعال والاساسي في البيئة المدرسية ودور مدير المدرسة بخلق جو من الابداع والتميز وحب التعاون بين المدرسين في المدارس الثانوية ،وتركزت مشكلة البحث من خلال اطلاع الباحثتان على بعض المراجع و الدراسات السابقة التي تخص بموضوع البحث لاحظا في الآونة الأخيرة تراجع في أداء
... Show Moreملخـــص البحــــث
تطوير كتاب التربية الاسلامية للصف الثالث متوسط لا عداد جيل يؤمن بالله وملائكته وغرس الميول الصحيحة في تقوية اعادة صياغة الطلبة وتعزيز محبة الله تعالى ورسوله الكريم ( صلى الله عليه وسلم ) وال بيته الاطهار ( عليهم السلام ) واصحابه الكرام ( رضي الله عنهم اجمعين) من قبل مدرسي ومدرسات المادة . تضمن البحث منهج التربية الاسلامية للصف الثالث ال
... Show MoreThe Financial authority is considered as one of the most of benefited parts from financial statements which depends on it in process of accounting in taxes as basis to determine The Tax Base , but no confidence from financial authority part in objectivity of income financial information in them for many of limited companies led to no dependence on them to specify taxation contain & dependence on yearly regulations that issued them. To enhance the confidence of financial authority to these lists must meet its requirements, because the menus Fulfill the requirements of the financial authority increases the confidence in these statements and therefore reliable in determining the tax base. So this research aims to speci
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