The present study involves experimental analysis of the modified Closed Wet Cooling Tower (CWCT) based on first and second law of thermodynamics, to gain a deeper knowledge in this important field of engineering in Iraq. For this purpose, a prototype of CWCT optimized by added packing under a heat exchanger was designed, manufactured and tested for cooling capacity of 9 kW. Experiments are conducted to explore the effects of various operational and conformational parameters on the towers thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of air measured at intermediate points of the heat exchanger and packing. Exergy of water and air were calculated by applying the exergy destruction method on the cooling tower. Experimental results showed a significant performance improvement when using packing on the CWCT. It can be observed that the thermal efficiency for the CWCT with packing under a heat exchanger and CWCT with packing above the heat exchanger are approximately 40% and 25% higher than that of the CWCT without packing respectively. As another part of the experiment results, it is indicated that the exergy destruction is directly proportional to air flow rate, cooling water flow rate, inlet cooling water flow rate and inlet Air Wet Bulb Temperature (AWBT) whereas, it is inversely proportional with spray water flow rate. In comparison with the cooling capacity of the tower, it was found that the exergy destruction approximately less than 20%. Exergy efficiency behavior is inversely proportional with the behavior of the exergy destruction. Empirical correlations are obtained to predict water film heat transfer coefficient and air-water mass transfer coefficient considering the influences of operational parameters.
It was known that every left (?,?) -derivation is a Jordan left (?,?) – derivation on ?-prime rings but the converse need not be true. In this paper we give conditions to the converse to be true.
Water pollution is widely regarded as one of the most pressing global challenges, exacerbated by human progress in industrial, agricultural, and technological sectors. Wastewater often contains non-biodegradable heavy metals that accumulate in living organisms. This accumulation poses significant risks to both environmental ecosystems and human health. The structures and surface morphology were characterized by FTIR, UV-vis measurements, XRD, SEM, and AFM. TiO2 nanoparticles could remove heavy metal ions (Pb2+, Cd2+, and Cr3+) from two samples (laboratory samples and real samples from Babylon battery factory in Al-Waziriya, Baghdad/Iraq) and measured by AAS. The results indicated that the removal percentages of heavy metal ions by T
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This research aims at identifying the communicative habits and content reflections on the communication process, especially the young audience which is one of the main group for whom the announcements are made. Because young people face life with passion and aspiration making them respond to each effect used by the media in the design of the advertising using all the effective techniques, attractive methods for young children like depending on drama, technical tricks, music and logos easily to be remembered and responded to the desires of the young in their entertainment. This research also aims at identifying the impact of the internet as a channel of commercial advertising on the purchasing behavior of young people at the universities
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Day after day, Morsek literature 879-1018/1492-1609proves the completion of all literary branches starting from poetry with its different purposes to include prose with its various subjects. In 2016, a complete text of ‘the literature of Morsek journey
Day after day, Morsek literature 879-1018/1492-1609proves the completion of all literary branches starting from poetry with its different purposes to include prose with its various subjects. In 2016, a complete text of ‘the literature of Morsek journeys
المستخلص: يهدف البحث الى التعرف على بقاء اثر المعلومة عن طريق الاجابة عن السؤال: ما مدى بقاء اثر التعلم بين التعليم الالكتروني والتعليم االحضوري ؟ تم تطبيق البحث في العام الدراسي( 2020-2021 م) في العراق. تم استخدام المنهج الوصفي بالاسلوب المقارن في عقد مقارنة بين التعليم الالكتروني والتعليم الحضوري. وكان مجتمع البحث من طلبة المرحلة الرابعة كلية التربية للعلوم الصرفة – ابن الهيثم ,و العيتة من قسم الرياضيات الم
... Show Moreهدف البحث الى التعرف على تأثير تمرينات خاصة في تطوير بعض القدرات البدنية وانجاز مسابقة عدو(100) متر حواجز تحت (20) سنة. استخدمت الباحثتان المنهج التجريبي بتصميم المجموعة التجريبية ذات الاختبار القبلي والبعدي لملائمته طبيعة البحث. تم تحديد مجتمع البحث بالطريقة العمدية وهم عداءات 100م حواجز من فئة الشباب، واختيار عداءات نادي السليمانية بألعاب القوى وتم اختيار العينة بصورة قصدية بأسلوب الاختبارين القبلي والبعدي و
... Show Moreلما كانت الوظيفة الأساسية للغة هي الوظيفة التواصلية ، أو التبادل الكلامي بين المخاطب والمستمع ، فكان لا بد لهذه الوظيفة من آليات – لغوية وبلاغية – يستعملها المتكلم أو المرسل للخطاب الأدبي لتوجيه ذهن السامع أو المخاطب نحو ما يطرحه من أفكار ، ورؤى ، واقناعه عن طريق التواصل ، بمضمون الخطاب واستلزام سرعة الانجاز ، وتأسيساً على ذلك جاء هذا البحث لبيان هذه الآليات في الخطاب القرآني متمثلاً في سور الطور
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