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Experimental Study on the Effect of Insertion of Copper Lessing Rings in Phase Change Material (PCM) on the Performance of Thermal Energy Storage Unit
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Abstract

One of the most suitable materials to be used in latent heat thermal energy storage system (LHTES) are Phase change materials, but a problem of slow melting and solidification processes made many researchers focusing on how to improve their thermal properties. This experimental work concerned with the enhancing of thermal conductivity of phase change material. The enhancing method was by the addition of copper Lessing rings in phase change material (paraffin wax). The effect of diameter for the used rings was studied by using two different diameters (0.5 cm and 1cm). Also, three volumetric percentages of rings addition (3%, 6% and 10%) were tested for each diameter. The discharging process was done with four velocities for each case. The obtained results indicated that the maximum volumetric percentage gave a diminished time for melting and maximized the heat transfer in both PCM and air sides as compare with the case of no rings, but the effect of these rings had lower effect on the solidification time. In case of 1 cm rings diameter minimum time for melting was obtained for both 3% and 6% volumetric percentages as compared with the same percentages in case of 0.5 cm diameter rings, while the latter with 10% volumetric percentage overcomes the 1 cm diameter rings for the same previous percentage. Also it can be seen that the minimum velocity (v=1m/s) gave the utmost outlet temperature and with the maximum one (v=3m/s), the minimum solidification time achieved.

Keyword: Thermal energy storage systems, Latent heat storage, Phase change materials, Heat transfer enhancement.

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Publication Date
Thu May 21 2020
Journal Name
کلیة الآداب جامعة بغداد
أثر الرمز في تشكيل اللوحة الشعرية (شعر ديك الجن" 161 636 ه" انموذجا)
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يرسم الشاعر صورة بالكلمات، ومتى ما تتابعت الصور صارت تمثل لوحة شعرية على قدر كبير من الفنية والابداع, وقد أكثر ديك الجن في شعره من هذه اللوحات ويلاحظ القارئ أن الرمز يعمل عملا مهما في تشكيل اللوحة، وظهرت أنواع متعددة من اللوحات منها اللوحة الرثائية, والغزلية, ومن الرموز التي وظفها ديك الجن رمز الظبي, رمز الديك, واستعمل رمز القبر وظهرت لوحات متنوعة في شعره، ومنها اللوحة الخمرية التي تجعل للخمرة احساسا ومشاعر وا

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Publication Date
Tue Mar 24 2009
Journal Name
كتاب الوقائع /المؤتمر العلمي الثالث لكلية العلوم جامعة بغداد
Using antibiotics as mutagenic and curing agents for Prodigiosin Production By Serratia marcescens
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The effect of different antibiotics on growth pigment and plasmid curing of Serratia marcescens were studied, S. marcescens was cultured in media containing(16_500)µg/ml of antibiotics, curing mutants unable to produce prodigiosin and lost one plasmid band were obtained of of ampicillin, amoxillin, antibiotics concentrations (64 500) µg/ml metheprim, ultracloxam, azithromycin, cephalexin and erythromycin treated with (350 500) µg/ml of The mutant cells rose- light color and and refampicin revealed S.marcescens inhibited ciprodar and tetracyclin, lincomycin did not lost the plasmid band chlaforan

Publication Date
Wed Jun 01 2005
Journal Name
Journal Of The College Of Languages (jcl)
الاحاسيس القومية والوطنية في الادب التركماني من خلال شعر ونثر الشاعر خضر لطفي
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Vatan ve hürriyet aşkının ilk ve en Kuvvetli örneklerinden Türkmen topraklarında yetişen yüzlerce Şairlerden biri Hıdır Lütfü’dür. Düşmana yar, öz evladına ağyar, yumuşak tabiatlı, yardımı ve milletini seven bir insandır. Şairin duygusu her dem yükseklere yücelirdi. O bilgili bir şair olduğu için şiirinde türlü türlü bilgi ile ögütleri arkasında bırakmamış onun duygusu bir bulak gibi her dem durmadan coşardı.
Onun en çok sevdiği varlıklar yurdu ile ulusuydı, ve tek acısı onların ilerleme ile yükselemesi içın bir haykırıydı.
Şair her zaman yurdunun ufukunda dolaşıp ulusunun bugünkü ve geleck torunları için yanıklı duyguları ile bir yol gosterıci gibi olmuştur.

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Publication Date
Sat Dec 29 2018
Journal Name
Journal Of Planner And Development
اثر العامل الديني في تخطيط المدينة العربية والعمارة الاسلامية مدينة النجف الاشرف أنموذجاً
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Publication Date
Mon Jun 01 2020
Journal Name
مجلة جامعة الانبار لللعلوم القانونية والسياسية
تقويم قواعد إدارة الشركات في ضوء قانون الشركات العراقي رقم 21 لسنة 1997،
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تقويم قواعد إدارة الشركات في ضوء قانون الشركات العراقي رقم 21 لسنة 1997،

Publication Date
Thu Dec 22 2022
Journal Name
مجلة الزرقاء للبحوث والدراسات
صياغة استراتيجية الامن القومي للدولة في ضوء ادراك التهديدات المتغيرة : الاستراتيجية الروسية انموذجا
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Publication Date
Mon Jun 04 2012
Journal Name
المؤتمر العلمي الدولي الاول
اهمية بعض القياسات الجسمية والبدنية بمستوى الانجاز الرقمي في فعاليه التجديف (الكاياك) 200م
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Publication Date
Sat Feb 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Solve travelling sales man problem by using fuzzy multi-objective linear programming
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   The main focus of this research is to examine the Travelling Salesman Problem (TSP) and the methods used to solve this problem where this problem is considered as one of the combinatorial optimization problems which met wide publicity and attention from the researches for to it's simple formulation and important applications and engagement to the rest of combinatorial problems , which is based on finding the optimal path through known number of cities where the salesman visits each city only once before returning to the city of departure n this research , the benefits  of( FMOLP)   algorithm is employed as one of the best methods to solve the (TSP) problem and the application of the algorithm in conjun

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Publication Date
Sun Oct 06 2013
Journal Name
Journal Of Educational And Psychological Researches
رؤية وانموذج- مقترح للارشاد النفسي والتوجيه التربوي في ظل نظام ادارة الجودة الشاملة
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The global challenges of contemporary facing societies urge to seek and move to adopt the style conscious in the face of these challenges and work on the investment of human resources and energies humanitarian efficient and effective for the development of the institutional and Management and make it more efficient and effective and meets the requirements and keep pace with global developments , and more aspects of managerial aim is Total Quality Management , as it has become thanks to the sheer amount and large accelerated technical developments and information and communication technologies , which feature of this era , and in the field of education , the charge of it are seeking through the application of total quality management to b

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Publication Date
Mon Jan 01 2018
Journal Name
مجلة الآداب والعلوم الإنسانیة
الأداء الاعلامي بين الرضا الوظيفي و المهنية للمرأة الاعلامية في القنوات الفضائية العراقية
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ﺔﻴﻋﺍﺫﻹﺍ ﺕﺎﻴﻨﻘﺘﻟﺍ ﻡﺍﺪﺨﺘﺳﺍ ﰲ ﲑﺒﻛ ﺭﻮﻄﺗ ﻦﻣ ﻝﺎﺼﺗﻻﺍ ﺮﺼﻋ ﻩﺪﻬﺷ ﻱﺬﻟﺍ ﺖﻗﻮﻟﺍ ﰲ ﺔﻴﻧﻮﻳﺰﻔﻠﺘﻟﺍﻭ ﺍ ﺢﺴﻓ ﰲ ﻢﻬﺳﺃ ﺕﺎﻄﶈﺍ ﺀﺍﻮﺳ ﺔﻴﻧﻮﻳﺰﻔﻠﺘﻟﺍ ﺕﺍﻮﻨﻘﻟﺍ ﺚﺒﻟ ﻊﺳﺍﻮﻟﺍ ﻝﺎ ( ﺔﻴﺿﺭﻷﺍ ﺔﻴﻠﺑﺎﻜﻟﺍ ﻭﺃ ﺔﻴﺋﺎﻀﻔﻟﺍ ﻭﺃ ( ﱵﻟﺍ ﺔﺻﺎﳋﺍ ﺔﻴﺋﺎﻀﻔﻟﺍ ﺕﺍﻮﻨﻘﻟﺍ ﻦﻣ ﺪﻳﺪﻌﻟﺍ ﺭﻮﻬﻇ ﰲ ﺎﻀﻳﺃ ﺪﻋﺎﺳ ﺎﳑﻭ ، ﺕﺎﻴﺋﺎﻀﻔﻟﺍ ﺭﻮﻬﻇ ﻚﻟﺫ ﻞﺒﻗ ﺩﺎﺳ ﻥﺃ ﺪﻌﺑ ﺔﻴﻣﻮﻜﺣ ﲑﻏ ﺕﺎﻴﻌﲨ ﻭ

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