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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 Jan 02 2020
Journal Name
Arab Science Heritage Journal
الظاهرة اللغوية بين الوص ف والتفسير أث ر المفاهي م الكل ي ة في التوفيق بين الاتجاهين العقلاني والطبيعي في دراس ة اللغ ة البشرية
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This research investigates modern linguistics in terms of the “universality” concept, through which linguistics shifted its attention from the description of the phenomenon into finding an interpretation of it. Then it investigates what needs interpretation in the language

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Publication Date
Thu Jan 02 2020
Journal Name
Arab Science Heritage Journal
الظاهرة اللغوية بين الوص ف والتفسير أث ر المفاهي م الكل ي ة في التوفيق بين الاتجاهين العقلاني والطبيعي في دراس ة اللغ ة البشرية
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This research investigates modern linguistics in terms of the “universality” concept, through which linguistics shifted its attention from the description of the phenomenon into finding an interpretation of it. Then it investigates what needs interpretation in the language

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Publication Date
Sun Jun 24 2018
Journal Name
Journal Of Pharmacy Research
Transdermal drug delivery system: A review
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Transdermal drug delivery has made an important contribution to medical practice but has yet to fully achieve its potential as an alternative to oral delivery and hypodermic injections. Transdermal therapeutic systems have been designed to provide controlled continuous delivery of drugs through the skin to the systemic circulation. A transdermal patch is an adhesive patch that has a coating of drug; the patch is placed on the skin to deliver particular amount of drug into the systemic circulation over a period of time. The transdermal drug delivery systems (TDDS) review articles provide information regarding the transdermal drug delivery systems and its evaluation process as a ready reference for the research scientist who is involved

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Publication Date
Sat Jun 30 2012
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Thickening Time and Compressive Strength Correlations for Bentonitic- Class "G" Cement Slurries
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Empirical equations for estimating thickening time and compressive strength of bentonitic - class "G" cement slurries were derived as a function of water to cement ratio and apparent viscosity (for any ratios). How the presence of such an equations easily extract the thickening time and compressive strength values of the oil field saves time without reference to the untreated control laboratory tests such as pressurized consistometer for thickening time test and Hydraulic Cement Mortars including water bath ( 24 hours ) for compressive strength test those may have more than one day.

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Publication Date
Mon Oct 22 2018
Journal Name
Journal Of Economics And Administrative Sciences
Using simulation to compare between parametric and nonparametric transfer function model
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In this paper, The transfer function model in the time series was estimated using different methods, including parametric Represented by the method of the Conditional Likelihood Function, as well as the use of abilities nonparametric are in two methods  local linear regression and cubic smoothing spline method, This research aims to compare those capabilities with the nonlinear transfer function model by using the style of simulation and the study of two models as output variable and one model as input variable in addition t

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Publication Date
Thu Mar 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
السياسة الضريبية المحلية في ظل العولمة ( مع إشارة خاصة لالسياسة الضريبية المحلية في ظل العولمة ( مع إشارة خاصة لبلدان جنوب شرق آسيا)بلدان جنوب شرق آسيا)
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تركت العولمة المتسارعة أثرا عميقا على مدى واسع من السياسات والتطبيقات الاقتصادية في كل من الدول النامية والمتقدمة على حد سواء, إذ نشأت الأنظمة الضريبية الحالية عندما نمّط كل بلد سياسته الضريبية بشكل تركز معه على متطلبات الاقتصاد المحلي, وعندما كانت تعقد المفاوضات بين الأمم المختلفة حول المعاملات الضريبية والاتفاقات الضريبية كانت تجري في إطار من هيمنة السياسة الضريبية المحلية.

لكن العولم

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Publication Date
Thu Apr 07 2022
Journal Name
Journal Of The College Of Basic Education
تاثير تمرينات خاصة في السرعة الادراكية وتعلم بعض المهارات الارضية بالجمناستك
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Publication Date
Sun Apr 23 2023
Journal Name
مجلة الجامعة العراقية
قضايا أخلاقية في العل م اخلاقيات العلم والتكنولوجيا وتدريس الكيميا ء
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تهدف هذه المقالة إلى توضيح أخلاقيات العلم وضوابطه التي يجب على من يعمل في هذا المجال أن يكون متحلي بها حتى يحافظ على القيم والأخلاق الفاضلة والموروثة من الآباء والاجداد والنابعة من الصالحين والاخيار لديم ومة الحياة بأفضل وجه وكما يتمناه الكل وكذلك عدم تجاوز الحدود التي تؤدي إلى الأض ا رر بالمجتمع والبيئة . وتوضيح الحدود الغير مسموح بتجاوزها في مجال العلم والتكنولوجيا ومن هذه الأخلاقيات أو الضوابط التي يجب أن

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
التضخم في العراق واحتساب مساهمة المجاميع السلعية فيه للمدة 2004 - 2009
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The inflation phenomenon inherent to all economies in the world, including Iraq, and to find out the reasons for this phenomenon must be measured impact on the national economy, and is the index of consumer prices of the most common measure of inflation in order to find the means and the treatments needed and this can be reached through the study of the role of aggregates   Commodity and its impact on the general trend of cash inflation, in  Iraq for the period 2004 2009 to determine the groups lead to inflation in Iraq, where it emerged that the group rent is ranked first in the proportion of its contribution to the index of consumer prices, and food group is ranked second. The fuel and lighting group ranked third.

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
ملامح معاییر نقدیة في مقامة الشعراء (الموفیة) للسرقسطي ت ٥٣٨ ھ
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Stop and stop Alsergsti classed many of the characteristics of great poets and
literary arts and persuasions, in Mqamth cash cash Antzmtha three criteria: the
standard of Islam and the standard time, and Maaartadd purposes of poetry. This
has had its effect on lighting stand many of the goals of the poets and their
attitudes.
The first criterion: Those who study the positions of Alsergsti to poetry and
poets must be discerned his money comes from the spirit of Islam as a religion and
creed and a system, a position that is encouraging him wherever expressed, such as
the Muslim community the new values, away from the vulgarity, which contributed
to the formulation of the standard of religious poetry criticism.

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