Preferred Language
Articles
/
joe-632
Exergy Analysis of a Domestic Refrigerator
...Show More Authors

An energy and exergy thermodynamic analysis using EES program was done for a domestic refrigerator working with R-134a using vapor compression refrigeration cycle. The analysis deals with the system component, i.e. compressor, condenser, evaporator and the expansion device. The analysis depends on the entropy generation minimization approach to improve the refrigerator performance by exploring the optimum design points. These design points were derived from three different theories governing the entropy generation minimization using exergy analyzing method. These theories were first applied to find the optimum balance between the hot inner condenser area and the cold inner evaporator area of the refrigerator and between its hot and cold thermal conductances. Nine types of condensers were used according to its internal surface area and thermal conductance, in order to reach the minimum entropy generation in the refrigerator. The results showed that the compressor has the lowest exergy efficiency of 25%. The expansion device was the second component after the compressor with exergy efficiency of 92%, followed by the condenser with an efficiency of 93%. The evaporator was found to have an exergy efficiency of 98 %. The experimental tests were repeated for the nine condensers sizes with three different ambient temperatures 25℃, 30℃ and 35℃.  The exergy analysis showed that the design of the refrigerator mainly depends on thermal conductance calculations rather than the surface inner area estimation.

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Jul 01 2015
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
APPROPRIATENESS OF EUCALYPTUS CAMAL / DULENSIS, CASUARINA EQUISETIFOLIA AND OLEA EUROPAEA TREES IN SHELTERBELT OF AL-ASHRAF NAJAF CITY
...Show More Authors

    The research has conducted on shelterbelt of Al-Ashraf Najaf city to explore suitability of four Eucalyptus camaldulensis Dehnh. Forms and two other tree species; Casuarina equisetifolia and Olea europaea to the local dominant sever conditions. Development in growth was studied through the interval of five years. Growth parameters included height, DBH stem diameter, main stem height, crown diameter, and stem girth were investigated. Distance from water supply was inspected, too. Results showed superiority of E. camaldulensis upon other species. Investigations showed weakness in growth of C. equisetifolia where most of trees could not resist because of their position in oppos

... Show More
View Publication Preview PDF
Publication Date
Wed Oct 28 2015
Journal Name
Al-khwarizmi Engineering Journal
Effect of Bearing Compliance on Thermo-hydrodynamic Lubrication of High Speed Misaligned Journal Bearing Lubricated with Bubbly Oil
...Show More Authors

Abstract

In the present work  the effect of bearing compliance on the performance of high speed misaligned journal bearing lined with a compliant PTFE liner lubricated with bubbly oil at high speeds has been studied. The effect of induced oil film temperature due to shearing effect has been implemented. Hydrodynamic effect of the complaint bearing and the influence of aerated oil have been examined by the classical thermohydrodynamic lubrication theory modified to include the effect of oil film turbulence and oil film temperature with suitable models for bubbly oil viscosity and density. The effect of liner elastic deformation has been implemented by using Winkler model. The effects of variable density and s

... Show More
View Publication Preview PDF
Publication Date
Thu Feb 19 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluating the effect of silver nanoparticles incorporation on antifungal activity and some properties of soft denture lining material
...Show More Authors

Background: Colonization of soft denture liners by Candida albicans and other microorganisms continued to be a serious problem. The aim of this study was to evaluate the effect of incorporating silver nanoparticles into heat cured acrylic-based soft denture liner on the antifungal activity, and on water sorption, solubility, shear bond strength and color change of the soft lining material. Furthermore, evaluating the amount of silver released. Materials and methods: Silver nanoparticles were incorporated into soft denture liner in different percentages (0.05%, 0.1% and 0.2% by weight). Four hundred and twenty specimens were prepared and divided into five groups according to the test to be performed. The antifungal activity of the soft liner

... Show More
View Publication Preview PDF
Publication Date
Fri Sep 30 2022
Journal Name
College Of Islamic Sciences
Principles of war and jihad to protect the environment and civilians in times of war in Islamic Sharia
...Show More Authors

Research summary

Islam protects the environment and civilians in peace and war, and in international humanitarian law protection of the environment and civilians in international conflicts only. As for wars and internal conflicts, it is not within the jurisdiction of international humanitarian law. In Islamic law, the principles of protecting the environment and civilians are fixed in all wars and conflicts, whether internal or external, local. or international.

Islam laid down moral principles in war, including:

- Preserving the environment and avoiding corruption in the land by burning trees and killing animals unnecessarily.

- Not to be exposed to non-combatants, including women, boys, the elderly, the disa

... Show More
View Publication Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Journal Of Population Therapeutics And Clinical Pharmacology
Accuracy of Office Hysteroscopy in Diagnosis of Endometrial Pathologies Compared to Ultrasound and Histopathology in Baghdad Teaching Hospital
...Show More Authors

View Publication
Scopus (6)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Wed Jun 01 2022
Journal Name
Iraqi Journal Of Physics
Theoretical Investigations of Electronic and Optical Properties of Vanadium Doped Wurtzite Zinc Oxide from First Principle Calculation Method
...Show More Authors

In this study lattice parameters, band structure, and optical characteristics of pure and V-doped ZnO are examined by employing (USP) and (GGA) with the assistance of First-principles calculation (FPC) derived from (DFT). The measurements are performed in the supercell geometry that were optimized. GGA+U, the geometrical structures of all models, are utilized to compute the amount of energy after optimizing all parameters in the models. The volume of the doped system grows as the content of the dopant V is increased. Pure and V-doped ZnO are investigated for band structure and energy bandgaps using the Monkhorst–Pack scheme's k-point sampling techniques in the Brillouin zone (G-A-H-K-G-M-L-H). In the presence of high V content, the ban

... Show More
View Publication Preview PDF
Crossref (5)
Crossref
Publication Date
Sun Mar 19 2023
Journal Name
Journal Of Educational And Psychological Researches
Special Education Teachers’ Perceptions of the Factors lead to School Bullying of Students with Intellectual Disabilities in Asir
...Show More Authors

Abstract

This study aims to identify the most prominent factors that lead to bullying of students with intellectual disabilities in primary and middle schools from the perspectives of special education teachers. A quantitative descriptive approach was utilized. A questionnaire was used as a tool for data collection. The sample consisted of (72) male and female teachers from the Asir region in the Kingdom of Saudi Arabia. The results revealed the most prominent factors that lead to bullying as follows: factors associated with the school and its policies, factors associated with peers, factors associated with students with intellectual disabilities, and factors associated with general education teachers. The findin

... Show More
View Publication Preview PDF
Publication Date
Thu Mar 18 2021
Journal Name
Energy & Fuels
Synergistic Effect of Nanoparticles and Polymers on the Rheological Properties of Injection Fluids: Implications for Enhanced Oil Recovery
...Show More Authors

New nanotechnology-based approaches are increasingly being investigated for enhanced oil recovery (EOR), with a particular focus on heavy oil reservoirs. Typically, the addition of a polymer to an injection fluid advances the sweep efficiency and mobility ratio of the fluid and leads to a higher crude oil recovery rate. However, harsh reservoir conditions, including high formation salinity and temperature, can limit the performance of such polymer fluids. Recently, nanofluids, that is, dispersions of nanoparticles (NPs) in a base fluid, have been recommended as EOR fluids; however, such nanofluids are unstable, even under ambient conditions. In this work, a combination of ZrO2 NPs and the polyacrylamide (PAM) polymer (ZrO2 NPs–PAM) was us

... Show More
Scopus (80)
Crossref (79)
Scopus Clarivate Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Environmental Advances
Stability and performance studies of emulsion liquid membrane on pesticides removal using mixture of Fe3O4Â nanoparticles and span80
...Show More Authors

View Publication Preview PDF
Scopus (19)
Crossref (16)
Scopus Crossref
Publication Date
Fri Jun 28 2024
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
Synthesis, Characterization, Molecular Docking, ADMET Study, and Antimicrobial Evaluation of New Mannich Bases of Isatin–Thiazole Imine Bases
...Show More Authors

Background: The isatin molecule is present in many natural substances, including plants and animals, and is used to prepare compounds with various biological activities. Objectives: To synthesize a new series of isatin derivatives with the expectation that they will have antimicrobial activity. Methods: Thiazole Schiff bases were synthesized from various Mannich bases of isatin to evaluate their antimicrobial properties. Initially, Mannich bases (2a–e) were synthesized by reacting isatin with formaldehyde and different secondary amines. Subsequently, they were treated with 2-aminothiazole to yield the final compounds (3a–e). Spectroscopic characterization was done via FT-IR and 1H-NMR. The antimicrobial screening was conducted o

... Show More
View Publication
Scopus (8)
Crossref (6)
Scopus Crossref