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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
Wed Feb 06 2019
Journal Name
Journal Of The College Of Education For Women
من اعجازات القرآن الكریم الأصل العضوي للنفط في سورة الاعلى
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The energy consider generally and specifically the petroleum energy
from the prior requirement of the population and nations, and the basics of the
survival of mankind and all the challenges for the sake of continuum, so
without this energy the life of ankind being varied, so far the life is still as a
fact on the planet earth, and suppose the life may continue as the willing of
Allah ,that the events and the standards and the degree of development is still
as it is, in another word no any technical developments and no any
entertainment no transportation and also there is no demographic domination
for the whole lands belonging to Allah, certainly no way to talk more on what
we and the others knew, what is the g

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Publication Date
Fri Jun 01 2007
Journal Name
Journal Of The College Of Languages (jcl)
Ali Şir Nevai Muhakemetül-lugateyn Eserinin Sesbilimi Özellikleri
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Önsöz
Ali Şir Nevai’nin vücuda getirdiği edebi Çağatayca, edebi ve canlı bazı Türk şivelerinin işlenmesinden ve kaynaşmasından hasıl olmuştur. Bu gün bu dilin
fonetik bünyesi hakkında, en çok bilgi veren, yine Nevai’nin kendisidir. Onun―Muhakeemet-ül-luğateyn‖ adlı eseri, bu bakımından büyük bir değer taşımaktadır.Bu eserinde Nevai, bir taraftan Türk dilinin Farsçaya üstünlüğünü ispata kalkışken, bir taraftan da kendi Türkçesinin fonetik ve morfolojik özelliklerini belirtmiştir. O, Arab imlası kaidesi üzerine ayni şekilde yazılarak, semantik yönden başka başka manalarda kullanılan kelimeleri sıralarken, açık bir surette, edebi Çağataya şivesinin fonetik bünyesini d

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Publication Date
Thu Nov 08 2018
Journal Name
Arab Science Heritage Journal
براعة براعة علماء الأندلس في الزراعة من خلال مؤلفاتهم الفلاحية
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           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 ,

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Publication Date
Wed May 11 2022
Journal Name
Journal Of The College Of Law/al-nahrain University
التزام الملاك بنفقات صيانة الاجزاء المشتركة وأعبائها في الاسكان العمودي.
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The phenomenon of multi-class construction and landlords has increased in Iraq, and this is not justified except because of the change in the economic and social conditions in it, because like any social system interacts with what happens in society, whether it is positive or negative, and since the vertical housing system contains common parts and these parts need to Maintenance and preservation, and in order to continue to perform the construction and other parts in an effective and regular manner for a long period of time and with appropriate efficiency, it must be maintained, and maintenance is one of the most important and difficult problems facing the partners. It is recognized that it is not possible to understand these practical dif

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Publication Date
Fri Jan 01 2016
Journal Name
Journal Of The College Of Languages (jcl)
Türkçe'de –madan, -meden Ulaç Ekinin Yazılışı ve kullanılışı
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Araştırmamın adı: Türkçe'de –madan, -meden Ulaç Ekinin Yazılışı ve Kullanılışıdır.

      Ulaçlar, kişi ve zaman kavramı olmadan temel cümlenin yada yan cümlenin yüklemini niteleyen, cümlede genellikle zarf tümleci olarak görev yapan fiilimsilerdir. İkinci bir görevleri yardımcı fiillerle birlikte kullanılarak birleşik fiiller kurmak olan ulaçlar, cümlede bağlaç görevinde kullanılabilirler, ve birleşik cümleler kurabilirler. Bazı ulaç ekleri zarf, edat gibi kalıcı sözcük yapımında da kullanılırlar.

      Bu araştırmada Orhun Türkçesi'nde başlayıp Türkiye Türkçesine kadar uzanan tarihi dönemlere ait eserlerden –m

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Publication Date
Thu Jan 03 2019
Journal Name
Journal Of Planner And Development
دور قوانين الاستثمار في الانتاج السكني منطقة الدراسة- محافظة السليمانية
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Publication Date
Fri Jan 04 2019
Journal Name
Journal Of Planner And Development
اللامركزية أسلوب تنموي إقليمي لمعالجة مشاكل التحضر المفرط في العراق
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Publication Date
Mon Jun 01 2020
Journal Name
مجلة اشراقات تنموية
معوقات البحث العلمي التطبيقي لطلبة الدراسات العليا في الجامعات العراقية
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على الرغم من أن الجامعات والمراكز والمؤسسات العلمية في الجامعات العراقية تزخر بالعديد من الكوادر والخبرات العلمية والأكاديمية المؤهلة علمياً وفنياً لانتاج البحوث العلمية والاشراف على طلبة الدراسات العليا، غير ان عملية انتاج الابحاث العلمية التطبيقية على وجه الخصوص تعترضها مجموعة من الصعوبات والمعوقات التي استطلعها الباحثين اما من خلال التجربة الشخصية, او من خلال استطلاعات اراء طلبة الدراسات العليا والب

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Publication Date
Wed Jan 11 2017
Journal Name
Journal: Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Characterization of some Metal Complexes with (3Z ,5Z, 8Z)-2-azido-8-[azido(3Z,5Z)-2-azido-2,6- bis(azidocarbonyl)-8,9-dihydro-2H-1,7-dioxa-3,4,5- triazonine-9-yl]methyl]-9-[(1-azido-1-hydroxy)methyl]-2H1,7-dioxa-3,4,5-triazonine – 2,6 – dicarbonylazide(L-AZ) .
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The reaction of LAs-Cl8 : [ (2,2- (1-(3,4-bis(carboxylicdichloromethoxy)-5-oxo-2,5- dihydrofuran-2-yl)ethane – 1,2-diyl)bis(2,2-dichloroacetic acid)]with sodium azide in ethanol with drops of distilled water has been investigated . The new product L-AZ :(3Z ,5Z,8Z)-2- azido-8-[azido(3Z,5Z)-2-azido-2,6-bis(azidocarbonyl)-8,9-dihydro-2H-1,7-dioxa-3,4,5- triazonine-9-yl]methyl]-9-[(1-azido-1-hydroxy)methyl]-2H-1,7-dioxa-3,4,5-triazonine – 2,6 – dicarbonylazide was isolated and characterized by elemental analysis (C.H.N) , 1H-NMR , Mass spectrum and Fourier transform infrared spectrophotometer (FT-IR) . The reaction of the L-AZ withM+n: [ ( VO(II) , Cr(III) ,Mn(II) , Co(II) , Ni(II) , Cu(II) , Zn(II) , Cd(II) and Hg(II)] has been i

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Publication Date
Tue May 01 2012
Journal Name
Iraqi Journal Of Physics
Argon plasma needle source
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Non thermal argon plasma needle at atmospheric pressure was generated. The experimental set up is based on very simple and low cost electric components that generate electrical field sufficiently high at the electrodes to ionize various gases, which flow at atmospheric pressure. The high d.c power supply is 7.5kV peak to peak, the frequency of the electrical field is 28kHz, and the plasma power less than 15W. The plasma is generated using only one electrode. In the present work the voltage and current discharge waveform are measured. Also the temperature of the working Ar gas at different gas flow and distances from the plasma electrode tip was recorded

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