Preferred Language
Articles
/
alkej-265
Experimental Study on the Effect of Insertion of Copper Lessing Rings in Phase Change Material (PCM) on the Performance of Thermal Energy Storage Unit
...Show More Authors

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Educational And Psychological Researches
تقويم محتوى كتاب الاحياء للصف السادس العلمي من وجهة نظرمدرسي ومدرسات الاحياء في محافظة كركوك
...Show More Authors

The present study aims to identify the extent to which biology book of sixth grade achieves the basic scientific aspects in light of its scientific objectives. To achieve this goal, the researcher needed to build two questionnaires to evaluate the biology book for sixth-grade. To answer the questions of the study, the researcher used the following statistical methods : the weighted average, and percentages; and to identify the extent to match the perspective of teachers of the material with the perspective of a researcher in each paragraph of the questionnaire as well as the degree of severity of each paragraph in the book neighborhoods sixth-grade has reached Aalbagesh to several of the most important results: 1. All the teachers were w

... Show More
View Publication Preview PDF
Publication Date
Mon Oct 01 2007
Journal Name
Journal Of Educational And Psychological Researches
تقويم طرائق التدريس والتقنيات التربوية والأختبارات التحصيلية لدى أعضاء الهيئة التدريسية في جامعتي بغداد والنهرين
...Show More Authors

أن أزدياد أعداد الطلبة في معظم دول العالم ، والتوسع في التعليم العالي ، أدى الى أستيعاب أعداد كبيرة في المؤسسات التعليمية من حملة الشهادات العليا الماجستير خاصة والدكتوراه ، وأن برامج الدراسات العليا وضعت لأعداد باحثين مختصين في مجالات عدة منها التدريس وما يتطلبه من مهارات مختلفة ، فأن قسماً منهم ليست لديه المعرفة النظرية والتطبيق العملي والمهارات اللازمة لأستخدام طرائق التدريس والتقنيات التربوية أث

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 18 2023
Journal Name
Arab Science Heritage Journal
التعايش السلمي في الاسلام بين التنظير والتطبيق عهد الامام علي (عليه السلام) للاشتر النخعي / انموذجا
...Show More Authors

     Peaceful coexistence is not seen as a new topic of secretions of modern civilization, a requirement to solve the problems of our era or one of the indications of urgent immediate needs, rather, tolerance is considered basis for building a state. Therefore, we can touch on the principles and basics of tolerance in the Holy Qur’an, the speeches of the Messenger (may God bless him and grant him peace) and his hadiths, and the principle of brotherhood that he established

View Publication Preview PDF
Publication Date
Sat Nov 10 2018
Journal Name
Journal Of Planner And Development
(دور الوعي البيئي لدى الأسرة العراقية في التخلص من النفايات الصلبة) (مدينة الرمادي – حي العزيزية)
...Show More Authors

View Publication Preview PDF
Publication Date
Mon Nov 19 2018
Journal Name
Arab Science Heritage Journal
مصطلح مصطلح (i3-gal2) في ضوء نصوص مسمارية غير منشورة من عصر سلالة أور الثالثة
...Show More Authors

The verbal formula // i3-gal2 //is a commonly form in the written Sumerian economic texts, starting from the early dynastic period (2900-2372 BC), ending with the Ur III dynasty (2112-2004 BC).  This formula has appeared either without infixes, or accompanied by infixes like / in-da-gal2/,  corresponded in Akkadian the formula: ibaššu ,which is  means "to found, to Storage ", As to the formula / da / come to indicate "to found with, to storage with--).

View Publication Preview PDF
Publication Date
Sat Dec 01 2007
Journal Name
Journal Of Economics And Administrative Sciences
تصـمـيم ومــحـاكاة سلسلة التجـهـيز الالكترونية دراسـة حـالة في الـشـركة الـعـامـة للـصـناعـات الـصـوفية – مـعـمل 1 أيـار
...Show More Authors

Supply Chain Management (SCM) attempts to a create a synchronization of the firm’s processes and those of the supplier to match the flow of materials, services, and information with the customer demand. Due to its importance, the SCM has become inevitable to modern companies. Therefore this research work has been conducted to set a theoretical and applied basis to assist the 1 AYAR factory in adopting the Electronic Supply Chain (e-SC).  To accomplish that the searchers applied many tools such as: quantitative and qualitative analysis, process analysis, Visual Basic software, Monte Carlo Simulation to simulation the designed supply chain to compare its performance against the actual performance of the current supply chain

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Educational And Psychological Researches
أثر استراتيجية التدريس التبادلي في اكتساب مهارة قراءة الخريطة الجغرافية لدى طالبات الصف الخامس الأدبي
...Show More Authors

The aim of this study is to find out the effect of reciprocal teaching   on the fifth literary class pupils in acquiring the skill of geographic map reading. The researcher uses the partial experimental design/pre- post-test for two equivalent control and experimental groups.

   The population of the study is represented by the fifth literary class pupils at a school of the Directorate of Education /Baghdad Karkh second. The sample is selected randomly as section (A) the experimental group and section (C) the control group. The sample total number is (60) pupils, (30) pupils for each group. The two groups are equalized in the following variables: IQ, age and the pupils’ previous geog

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
New N-triaryl-substituted polyamides materials as light Emitters for semiconductors applications
...Show More Authors

     In this work, new di-acid monomers 4, 4’-di-carboxillic-2”-chloro-4”- nitro triphenylamine (Di-CO2H-1), 4, 4’- di-carboxylic -2”,4”,6”-trichloro-triphenylamine (Di-CO2H-2) were synthesized by reaction of p-cyanobenzofluride with two aromatic amines (2-chloro 4-nitro aniline and 2,4,6-trichloro aniline by aromatic nucleophilc substitution method to produce two di cyano intermediates compounds 4, 4’-Dicyano-2”-chloro-4”- nitro triphenylamine (Di-CN1) and 4, 4’-dicyano-2”,4”,6”-trichloro-triphenylamine (Di-CN2) which form final di-carboxylic monomers after alkaline hydrolysis. Finally, these monomers react with two different arom

... Show More
View Publication Preview PDF
Publication Date
Sun Feb 10 2019
Journal Name
Iraqi Journal Of Physics
Thermoelectric power for thermally deposited cadmium telluride films
...Show More Authors

Thermal evaporation method has used for depositing CdTe films
on corning glass slides under vacuum of about 10-5mbar. The
thicknesses of the prepared films are400 and 1000 nm. The prepared
films annealed at 573 K. The structural of CdTe powder and prepared
films investigated. The hopping and thermal energies of as deposited
and annealed CdTe films studied as a function of thickness. A
polycrystalline structure observed for CdTe powder and prepared
films. All prepared films are p-type semiconductor. The hopping
energy decreased as thickness increased, while thermal energy
increased.

View Publication Preview PDF
Crossref
Publication Date
Fri Jan 01 2021
Journal Name
Journal Of Intelligent Systems
Void-hole aware and reliable data forwarding strategy for underwater wireless sensor networks
...Show More Authors
Abstract<p>Reliable data transfer and energy efficiency are the essential considerations for network performance in resource-constrained underwater environments. One of the efficient approaches for data routing in underwater wireless sensor networks (UWSNs) is clustering, in which the data packets are transferred from sensor nodes to the cluster head (CH). Data packets are then forwarded to a sink node in a single or multiple hops manners, which can possibly increase energy depletion of the CH as compared to other nodes. While several mechanisms have been proposed for cluster formation and CH selection to ensure efficient delivery of data packets, less attention has been given to massive data co</p> ... Show More
View Publication Preview PDF
Scopus (8)
Crossref (5)
Scopus Clarivate Crossref