The objective of the study is developing a procedure for production and characterization of rice husk ash (RHA). The effects of rice husk (RH) amount, burning/cooling conditions combined with stirring on producing of RHA with amorphous silica, highest SiO2, lowest loss on ignition (LOI), uniform particle shape distribution and nano structured size have been studied. It is concluded that the best amount is 20 g RH in 125 ml evaporating dish Porcelain with burning for 2 h at temperature 700 °C combined with cooling three times during burning to produce RHA with amorphous silica, SiO2 90.78% and LOI 1.73%. On the other hand, cooling and stirring times affect the variation of nano structured size and particle shape distribution. However, no crystalline phases were found in RHA in all cases. Results proved that the Attritor ball mill was more suitable than vibration disk mill for pulverizing nano structured RHA with 50% of particle size (D50) lower than 45 mm and 99 % of particle size (D99) lower than 144 mm to nanosized RHA with D50 lower than 36 nm and D99 lower than 57 nm by grinding time 8.16 min to every 1 g RHA without changes in morphousity of silica.
In 2020 one of the researchers in this paper, in his first research, tried to find out the Modified Weighted Pareto Distribution of Type I by using the Azzalini method for weighted distributions, which contain three parameters, two of them for scale while the third for shape.This research compared the distribution with two other distributions from the same family; the Standard Pareto Distribution of Type I and the Generalized Pareto Distribution by using the Maximum likelihood estimator which was derived by the researchers for Modified Weighted Pareto Distribution of Type I, then the Mont Carlo method was used–that is one of the simulation manners for generating random samples data in different sizes ( n= 10,30,50), and in di
... Show MoreIt was the sayings of Andalusia scholars in agriculture based on experiments and theories that helped a lot in the success and development of agriculture in the Andalusia ,and also The divisions of the soil and out types and forms it helped a lot of to know arable of non-arable land earth and all off the determination of the color of repentance is important often discovered by agricultural scientists and that helped in the cultivation of certain crops in certain land without another land.and though each particular agricultural crops specific soil in which to live and not live in other soil ,
هدفت هذه الدراسة إلى تحديد أهم المشكلات النفسية، الصحية، الاجتماعية، الاقتصادية، التي يعاني منها كبار السن في مجتمع الدراسة وقد انبثق عن هذا الهدف الرئيس أسئلة هي:
- ما هي أهم المشكلات التي يعاني منها كبار السن في محافظة جرش /الكته من وجهة نظرهم؟
- ما هي أهم العوامل التي قد تؤدي إلى ظهور مشكلات لدى كبار السن ؟
- هل يعاني كبار السن من الأرامل والمطلقين (رجال ونساء
هدفت هذه الدراسة إلى التعرف على درجة استخدام معلمات الرياضيات لأدوات التقويم البديل من وجهة نظرهن، وتحديد إذا كانت توجد فروق ذات دلالة إحصائية تعزى لمتغير سنوات الخبرة التدريسية، ولتحقيق أهداف الدراسة تم استخدام المنهج الوصفي. وتكونت عينة الدراسة من 37 معلمة من معلمات الرياضيات في الحلقة الثانية من التعليم الأساسي في محافظة ظفار في سلطنة عُمان. وتم بناء استبانة مكونة من (21) فقرة موزعة على (4) محاور تمثل أدوات
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It’s good to study the historical sites because they determine the reason why Abu Jaafar Al-Mansour choose Baghdad the timeless Capital ,So it’s easy for us to reconnect the past and the present regarding to the city, and must understand how its important the geographic site selection, which is determined by ancient rivers, which were the basis on which the city was constructed in the various roles of historical and this is natural because the
It was the sayings of Andalusia scholars in agriculture based on experiments and theories that helped a lot in the success and development of agriculture in the Andalusia ,and also The divisions of the soil and out types and forms it helped a lot of to know arable of non-arable land earth and all off the determination of the color of repentance is important often discovered by agricultural scientists and that helped in the cultivation of certain crops in certain land without another land.and though each particular agricultural crops specific soil in which to live and not live in other soil
أهمية البحث ومشكلته:- تعد الطفولة من أهم المراحل العمرية في حياة الإنسان اذ يكون فيها الطفل غضاً من النواحي الجسمية والعقلية والنفسية، شديد القابلية للتأثر بالعوامل المختلفة المحيطة به الأمر الذي يبرز أهمية السنوات الخمس الأولى في تكوين شخصيته بصورة تترك طابعها فيه طيلة حياته. ومن أهم سمات هذه المرحلة نمو القوى العقلية والجسمية والنفسية، ومن جوانب نمو الطفل العقلية هي المفاهيم ا
... Show MoreThe aim of the present research is to construct a model to evaluate the software engineering subject in the third grade department of Computing, in colleges of education. Then, evaluating the software Engineering subject from the view point of staff members by applying the constructed model, and in order to achieve the second aim of the present research the researcher has to find answers to the following questions:- 1. What is the presence of the proposed evaluating model fields, which was prepared by the researcher for the third grade Soft Ware Engineering subject from the view point of staff members? 2. What is the presence of the items for the proposed evaluating model, which was prepared by the researcher for the third grade Soft War
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