Preferred Language
Articles
/
joe-346
Experimental Study on the Effect of Using Metallic Brushes on the Charging and Discharging Time of Thermal Energy Storage Unit
...Show More Authors

Phase change materials are known to be good in use in latent heat thermal energy storage (LHTES) systems, but one of their drawbacks is the slow melting and solidification processes. So that, in this work, enhancing heat transfer of phase change material is studied experimentally for in charging and discharging processes by the addition of high thermal conductive material such as copper in the form of brushes, which were added in both PCM and air sides. The additions of brushes have been carried out with different void fractions (97%, 94% and 90%) and the effect of four different air velocities was tested. The results indicate that the minimum brush void fraction gave the maximum heat transfer in PCM and reduced the time for melting for (ϵ=90%) up to 4.49 times as compare with the case of no brush. It can be seen that the addition of brushes in air side helped to reduce the solidification time and increase the convection heat transfer coefficient as the brush void fraction decreased. Also the minimum velocity (v = 1 m/s) gave maximum outlet temperature.

 

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Oct 25 2021
Journal Name
Iraqi Journal Of Science
The Thermal Effect on PLA And PLA / Curcumin Composite Properties under Positron Annihilation Lifetime Spectroscopy
...Show More Authors

     In this study, pure polylactic acid (PLA) and composite polylactic acid/ curcumin (PLA / Cur) were prepared by a suspension of ultrasonically agitated micrometer-sized curcumin powder, which was mixed with chloroform solvent  under slow mechanical stirring and incorporated into the PLA. The resulting suspension was used to cast free-standing PLA / Cur composite films. The filler content was chosen to be 2.0 wt % curcumin. Physical properties (glass transition, temperature, mechanical and thermodynamic) were analyzed by Positron Annihilation Lifetime Spectroscopy (PALS), which is a unique tool for analyzing the defects of polymer materials. The free volume and holebility of PLA and PLA / Cur were studied&nbsp

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Sat Mar 18 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of The Electromagnetic Field Intensity and Duration of Time on Some of The Morphological Characteristics of The Plant Safflower Carthamus tinctorius L.
...Show More Authors

 The experiment was carried out in the field of botanical garden belonging to the Department of Biology Sciences, College of Education for Pure Science -Ibn AL-Haitham ,Baghdad University. for the growing season. 2014 -2013 to study the effect of the electromagnetic field which included five different intensities (0,5,10,15,20) MT and three periods of time, namely, (1,2,3) an hour and their interaction on  some of the morphological characteristics of the safflower plant . designed experiment by Randomized Complete Block Design (RCBD) and three replicates per treatment, compared to the average using  less significant difference at the level of probability (0.05) , the results showed the following:- 1-Exposing seeds to diffe

... Show More
View Publication Preview PDF
Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The impact of the risks of foreign currency positions on the continuity of the economic unit : Applied research
...Show More Authors

The research aims to know the extent of the impact of the risks of foreign exchange centers represented in commitment risks, liquidity risks, and exchange rate risks on the continuity of the economic unit. The research in the light of its presentation of the intellectual, cognitive and applied contributions about the risks of foreign currency centers and the continuity of the economic unit, and represented the research community in the banking sector, and the sample included nine private commercial banks listed in the Iraq Stock Exchange, and they relied on the research on a time series consisting of four years that extended from one year 2017 to 2020. The research problem was the impact of the risks associated with foreign currency cent

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2023
Journal Name
8th Engineering And 2nd International Conference For College Of Engineering – University Of Baghdad: Coec8-2021 Proceedings
Effect of permeation grouting with nano-materials on shear strength of sandy soil: An experimental study
...Show More Authors

View Publication
Crossref (3)
Crossref
Publication Date
Mon Feb 18 2019
Journal Name
Iraqi Journal Of Physics
Effect of annealing temperature and laser pulse energy on the optical properties of CuO films prepared by pulsed laser deposition
...Show More Authors

In this work; copper oxide films (CuO) were fabricated by PLD. The films were analyzed by UV-VIS absorption spectra and their thickness by using profilometer. Pulsed Nd:YAG laser was used for prepared CuO thin films under O2 gas environment with varying both pulse energy and annealing temperature. The optical properties of   as-grown film such as optical transmittance spectrum, refractive index and energy gap has been measured experimentally and the effects of laser pulse energy  and annealing temperature on it were studied. An inverse relationship between energy gap and both annealing temperature and pulse energy was observed.

View Publication Preview PDF
Crossref (5)
Crossref
Publication Date
Mon Aug 14 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect OF Film Thickness And Annealing Time on Structural And Optical Propertieis Of The Oxides (Fe2030, Co304) And Their Mixtures
...Show More Authors

Thin film technology is one of the most important technologies
that have contributed to the development of semiconductors and their
applications in several industrial fields. The Iron Oxides (Fe20) and
(Co3O4) thin films and their applications are of importance, in that these
two materials are considered as important industrial materials, and used
in spectrally selective coating, temperature sensors, resistive heaters, and
photo cells.
Thin films of Iron Oxide (Fe20,), Cobalt Oxide (Co304) and
their mixtures in different ratios (75:25, 50:50, 25:75) were prepared by
the method of chemical spray pyrolysis deposition at different thicknesses
(77s t S200) nm on cover-glass substrates: thickness of (1) mm at

... Show More
View Publication Preview PDF
Publication Date
Wed May 01 2019
Journal Name
Materials Science And Engineering
Effect of nanoparticles on thermal conductivity of epoxy resin system
...Show More Authors
Abstract<p>In this paper the effect of mixing TiO2 nanoparticles with epoxy resin is studied. The TiO2 nanoparticles would be synthesis and characterized by scanning electron microscopy (SEM), XRD FTIR, for two particle sizes of 50 and 25 nm. The thermal conductivity is measured with and without composite epoxy resin; the results showed that the thermal conductivity was increased as nanoparticle concentration increased too. The thermal conductivity was increased as particle size decreased.</p>
Preview PDF
Scopus (8)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Energy Conversion And Management
Simultaneous energy storage and recovery in the triplex-tube heat exchanger with PCM, copper fins and Al2O3 nanoparticles
...Show More Authors

View Publication
Scopus (229)
Crossref (219)
Scopus Clarivate Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Applied Energy
Solidification enhancement with multiple PCMs, cascaded metal foam and nanoparticles in the shell-and-tube energy storage system
...Show More Authors

View Publication
Scopus (250)
Crossref (242)
Scopus Clarivate Crossref
Publication Date
Sat Feb 01 2025
Journal Name
Journal Of Physical Education
The Effect of Special Exercises on Developing Strength Endurance and Kayaking Achievement Time (500m) individually for the Advanced Kayak Athletes
...Show More Authors

View Publication